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Sample records for digital control system

  1. Precision digital control systems

    Science.gov (United States)

    Vyskub, V. G.; Rozov, B. S.; Savelev, V. I.

    This book is concerned with the characteristics of digital control systems of great accuracy. A classification of such systems is considered along with aspects of stabilization, programmable control applications, digital tracking systems and servomechanisms, and precision systems for the control of a scanning laser beam. Other topics explored are related to systems of proportional control, linear devices and methods for increasing precision, approaches for further decreasing the response time in the case of high-speed operation, possibilities for the implementation of a logical control law, and methods for the study of precision digital control systems. A description is presented of precision automatic control systems which make use of electronic computers, taking into account the existing possibilities for an employment of computers in automatic control systems, approaches and studies required for including a computer in such control systems, and an analysis of the structure of automatic control systems with computers. Attention is also given to functional blocks in the considered systems.

  2. Digital control systems. Verteilte Prozessleitsysteme

    Energy Technology Data Exchange (ETDEWEB)

    1984-01-01

    With a distinct description of the systems properties thin regulation shall provide a latter transparency for the use of digital control systems. The application of the new technique shall be facilitated, incitations for the further development shall be given and the compatibility of the systems shall be advanced. Moreover, the regulation can be used as criteria catalogue for the evaluation of digital systems.

  3. Digital control system of advanced reactor

    International Nuclear Information System (INIS)

    Peng Huaqing; Zhang Rui; Liu Lixin

    2001-01-01

    This article produced the Digital Control System For Advanced Reactor made by NPIC. This system uses Siemens SIMATIC PCS 7 process control system and includes five control system: reactor power control system, pressurizer level control system, pressurizer pressure control system, steam generator water level control system and dump control system. This system uses three automatic station to realize the function of five control system. Because the safety requisition of reactor is very strict, the system is redundant. The system configuration uses CFC and SCL. the human-machine interface is configured by Wincc. Finally the system passed the test of simulation by using RETRAN 02 to simulate the control object. The research solved the key technology of digital control system of reactor and will be very helpful for the nationalization of digital reactor control system

  4. Life-critical digital flight control systems

    Science.gov (United States)

    Mcwha, James

    1990-01-01

    Digital autopilot systems were first used on commercial airplanes in the late 1970s. The A-320 airplane was the first air transport airplane with a fly-by-wire primary flight control system. On the 767-X (777) airplane Boeing will install all fly-by-wire flight controls. Activities related to safety, industry status and program phases are discussed.

  5. Modernization of control system using the digital control system

    International Nuclear Information System (INIS)

    Carrasco, J. A.; Fernandez, L.; Jimenez, A.

    2002-01-01

    Nowadays, all plant automation tendencies are based on the use of Digital Control System. In big industrial plants the control systems employed are Distributed Control Systems (DCS). The addition of these systems in nuclear power plants,implies an important adaptation process, because most of them were installed using analog control systems. This paper presents the objectives and the first results obtained, in a modernization project, focused in obtaining an engineering platform for making test and analysis of changes prior to their implementation in a nuclear plant. Modernization, Upgrade, DCS, Automation, Simulation, Training. (Author)

  6. The development of ZPRL digital control system

    International Nuclear Information System (INIS)

    Hsu, Jin-Den; Yang, Sheau-Yieh; Shieh, Der-Jhy.

    1992-01-01

    Zero Power Reactor at Lung-Tan (ZPRL) is a small open-pool type research reactor located at Lung-Tan, Taiwan. The reactor achieved its first criticality in 1971. An analog control system has been used for almost over 20 years and the power regulating function is found gradually out of order. Therefore, we decided to develop a digital control system to replace the existing analog one. A prototype system has been developed and under on-line test now. The proposed ZPRL digital control system consists of three personal computers. These computers are used as (1) operator console, (2) data acquisition and control system, and (3) auxiliary and backup system. The operator console contains all the man-machine interface functions in the form of graphic display. The data acquisition and control system converts the analog signals into digital ones and feeds to the other two computers. The auxiliary and backup system normally emulates a strip chart recorder for the linear and logarithmic neutron powers and also acts as a transient recorder to keep the trace of the operating conditions on demand or when the reactor scrams. On-line test shows that the system does assure a satisfactory performance. It is not only as good as the analog system but also has the advantages of flexibility, testibility, and a user friendly man-machine interface. (author)

  7. Control theory of digitally networked dynamic systems

    CERN Document Server

    Lunze, Jan

    2013-01-01

    The book gives an introduction to networked control systems and describes new modeling paradigms, analysis methods for event-driven, digitally networked systems, and design methods for distributed estimation and control. Networked model predictive control is developed as a means to tolerate time delays and packet loss brought about by the communication network. In event-based control the traditional periodic sampling is replaced by state-dependent triggering schemes. Novel methods for multi-agent systems ensure complete or clustered synchrony of agents with identical or with individual dynamic

  8. Stability of digital feedback control systems

    Directory of Open Access Journals (Sweden)

    Larkin Eugene

    2018-01-01

    Lag time characteristics are used for investigation of stability of linear systems. Digital PID controller is divided onto linear part, which is realized with a soft and pure lag unit, which is realized with both hardware and software. With use notions amplitude and phase margins, condition for stability of system functioning are obtained. Theoretical results are confirm with computer experiment carried out on the third-order system.

  9. Distributed and recoverable digital control system

    Science.gov (United States)

    Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)

    2010-01-01

    A real-time multi-tasking digital control system with rapid recovery capability is disclosed. The control system includes a plurality of computing units comprising a plurality of redundant processing units, with each of the processing units configured to generate one or more redundant control commands. One or more internal monitors are employed for detecting data errors in the control commands. One or more recovery triggers are provided for initiating rapid recovery of a processing unit if data errors are detected. The control system also includes a plurality of actuator control units each in operative communication with the computing units. The actuator control units are configured to initiate a rapid recovery if data errors are detected in one or more of the processing units. A plurality of smart actuators communicates with the actuator control units, and a plurality of redundant sensors communicates with the computing units.

  10. Technological Improvements for Digital Fire Control Systems

    Science.gov (United States)

    2017-09-30

    Final Technical Status Report For DOTC-12-01-INIT061 Technological Improvements for Digital Fire Control Systems Reporting Period: 30 Sep...accuracy and responsiveness to call for fire. These prototypes shall be more cost effective, sustainable , use a higher percentage of alternative...of the quad charts and provide DOTC with sufficient initiative information, the Quarterly Report must be supplemented with data described below

  11. Automated hazard analysis of digital control systems

    International Nuclear Information System (INIS)

    Garrett, Chris J.; Apostolakis, George E.

    2002-01-01

    Digital instrumentation and control (I and C) systems can provide important benefits in many safety-critical applications, but they can also introduce potential new failure modes that can affect safety. Unlike electro-mechanical systems, whose failure modes are fairly well understood and which can often be built to fail in a particular way, software errors are very unpredictable. There is virtually no nontrivial software that will function as expected under all conditions. Consequently, there is a great deal of concern about whether there is a sufficient basis on which to resolve questions about safety. In this paper, an approach for validating the safety requirements of digital I and C systems is developed which uses the Dynamic Flowgraph Methodology to conduct automated hazard analyses. The prime implicants of these analyses can be used to identify unknown system hazards, prioritize the disposition of known system hazards, and guide lower-level design decisions to either eliminate or mitigate known hazards. In a case study involving a space-based reactor control system, the method succeeded in identifying an unknown failure mechanism

  12. Technical quality control - constancy controls for digital mammography systems

    International Nuclear Information System (INIS)

    Pedersen, K.; Landmark, I.D.; Bredholt, K.; Hauge, I.H.R.

    2009-04-01

    To ensure the quality of mammographic images, so-called constancy control tests are performed frequently. The report contains a programme for constancy control of digital mammography systems, encompassing the mammography unit, computed radiography (CR) systems, viewing conditions and displays, printers, and procedures for data collection for patient dose calculations. (Author)

  13. Fault tolerant digital control systems for boiling water reactors

    International Nuclear Information System (INIS)

    Chakraborty, S.; Cash, N.R.

    1986-01-01

    In a Boiling Water Reactor nuclear power plant, the power generation control function is divided into several systems, each system controlling only a part of the total plant. Presently, each system is controlled by conventional analog or digital logic circuits with little interaction for coordinated control. The advent of microprocessors has allowed the development of distributed fault-tolerant digital controls. The objective is to replace these conventional controls with fault-tolerant digital controls connected together with digital communication links to form a fully integrated nuclear power plant control system

  14. Experience of digital control systems in Scandinavian BWRs

    International Nuclear Information System (INIS)

    Rydahl, I.

    1989-01-01

    Since 1984 digital control systems have been in operation in various Scandinavian BWRs. Examples of such digital control systems are: dual microprocessor based system for complete control of radwaste plant, three channel recirculation control system, and three channel feedwater control system. This paper describes Swedish development from one channel through three channel analog control systems to digital systems. The author describes experience of digital control systems during design, testing, commissioning and operation. The main benefits of digital compared with analog technology are discussed. Especially the outstanding facility of using a built-in process simulator for commissioning and tuning. The use of digital technology in nuclear safety system and future plans are dealt with

  15. Rolls-Royce digital Rod Control System

    International Nuclear Information System (INIS)

    Pouillot, M.

    2010-01-01

    Full text of publication follows: Rolls-Royce has developed a new generation of Rod Control System, based on 40 years of experience. The fifth-generation Rod Control System (RCS) from Rolls-Royce offers a reliable, modular design with adaptability to your preferred platform, for modernization projects or new reactors. Flexible implementation provides the option for you to keep existing cabinets, which permits you to optimize installation approach. Main features for the power part: - Control Rod Drive Mechanism (CRDM) type: 3-coil. - Independent control of each sub-bank. - Each sub-bank is controlled by a cycler unit and 3 identical power racks, each including 4 identical power modules and a common power-supply module. - Coil-per-coil digital control: each power module embeds power-conversion, current-control, and current-monitoring functions for one coil. Control and monitoring are carried out by separate electronics in the module. Current is digitized and fully monitored by means of min-max templates. - A double-hold function is included: a power module assigned to a gripper will activate its coil if a fault risking to cause a reactor trip occurs. - Power modules are standardized, hot-pluggable and self-configured: a power module includes a set of parameters for each type of coil SG, MG, LC. The module recognizes the rack it is plugged in, and chooses automatically parameters to be used. Main benefits: - Reduced operational, maintenance, training, and inventory costs: standardization of power modules and integration of control and monitoring on the same PC-card lead to a drastic reduction of spare part types, and simplification of the system. - Easy maintenance: - Replacement of a power module solves nearly all failures due to current control or monitoring for a coil. It is done instantly thanks to hot-plug capability. - On the front plate of power-modules, LEDs provide useful information for diagnostic: current setpoint from cycler, output current bar

  16. Development of digital safety system logic and control

    International Nuclear Information System (INIS)

    Nishikawa, H.; Sakamoto, H.

    1995-01-01

    Advanced-BWR (ABWR) uses total digital control and instrumentation (C and I) system. In particular, ABWR adopts a newly developed safety system using advanced digital technology. In the presentation the digital safety system design, manufacturing and factory validation test method are shortly overviewed. The digital safety system consists of micro-processor based digital controllers, data and information transmission by optical fibers and human-machine interface using color flat displays. This new developed safety system meet the nuclear safety requirements such as high reliability, independence of divisions, operability and maintainability. (2 refs., 4 figs., 1 tab.)

  17. Digital control of wind tunnel magnetic suspension and balance systems

    Science.gov (United States)

    Britcher, Colin P.; Goodyer, Michael J.; Eskins, Jonathan; Parker, David; Halford, Robert J.

    1987-01-01

    Digital controllers are being developed for wind tunnel magnetic suspension and balance systems, which in turn permit wind tunnel testing of aircraft models free from support interference. Hardware and software features of two existing digital control systems are reviewed. Some aspects of model position sensing and system calibration are also discussed.

  18. Using the digital reactor control systems at NPP

    International Nuclear Information System (INIS)

    Schirl, G.; Hertel, J.

    2006-01-01

    A conception of application of the digital reactor control systems (RCS) at NPP is presented. The digital RCS architecture and safety ensuring are considered. The strategy and algorithm of the operating NPP equipping with the new digital RCS are given too [ru

  19. Combating obsolescence - ACR digital control systems design

    International Nuclear Information System (INIS)

    Tikku, S.; Raiskums, G.

    2006-01-01

    The ever increasing use of digital technologies and products to meet the control, automation and monitoring needs of the nuclear power plant - even though justified by the benefits it provides - comes with an increased risk of technological obsolescence happening through the course of the plant life. Some well considered strategies are being employed in the ACR design process to minimise this risk and alleviate the consequence if it happens. These include application of a modular overall architecture, adoption of international widely accepted standards to harmonise equipment qualification and software practices, production of control functional specifications that are not influenced by target platform, and careful selection of technologies and products. (author)

  20. Documenting control system functionality for digital control implementations

    International Nuclear Information System (INIS)

    Harber, J.; Borairi, M.; Tikku, S.; Josefowicz, A.

    2006-01-01

    In past CANDU designs, plant control was accomplished by a combination of digital control computers, analogue controllers, and hardwired relay logic. Functionality for these various control systems, each using different hardware, was documented in varied formats such as text based program specifications, relay logic diagrams, and other various specification documents. The choice of formats was influenced by the hardware used and often required different specialized skills for different applications. The programmable electronic systems in new CANDU designs are realized in a manner consistent with latest international standards (e.g., the IEC 61513 standard). New CANDU designs make extensive use of modern digital control technology, with the benefit that functionality can be implemented on a limited number of control platforms, reducing development and maintenance cost. This approach can take advantage of tools that allow the plant control system functional and performance requirements to be documented using graphical representations. Modern graphical methods supplemented by information databases can be used to provide a clear and comprehensive set of requirements for software and system development. Overview diagrams of system functionality provide a common understanding of the system boundaries and interfaces. Important requirements are readily traced through the development process. This improved reviewability helps to ensure consistency with the safety and and production design requirements of the system. Encapsulation of commonly used functions into custom-defined function blocks, such as typical motor control centre interfaces, process interlocks, median selects etc, eases the burden on designers to understand and analyze the detailed functionality of each instance of use of this logic. A library of encapsulated functions will be established for complex functions that are reused in the control logic development. By encapsulation and standardisation of such

  1. Lessons learned in digital upgrade projects digital control system implementation at US nuclear power stations

    International Nuclear Information System (INIS)

    Kelley, S.; Bolian, T. W.

    2006-01-01

    AREVA NP has gained significant experience during the past five years in digital upgrades at operating nuclear power stations in the US. Plants are seeking modernization with digital technology to address obsolescence, spare parts availability, vendor support, increasing age-related failures and diminished reliability. New systems offer improved reliability and functionality, and decreased maintenance requirements. Significant lessons learned have been identified relating to the areas of licensing, equipment qualification, software quality assurance and other topics specific to digital controls. Digital control systems have been installed in non safety-related control applications at many utilities within the last 15 years. There have also been a few replacements of small safety-related systems with digital technology. Digital control systems are proving to be reliable, accurate, and easy to maintain. Digital technology is gaining acceptance and momentum with both utilities and regulatory agencies based upon the successes of these installations. Also, new plants are being designed with integrated digital control systems. To support plant life extension and address obsolescence of critical components, utilities are beginning to install digital technology for primary safety-system replacement. AREVA NP analyzed operating experience and lessons learned from its own digital upgrade projects as well as industry-wide experience to identify key issues that should be considered when implementing digital controls in nuclear power stations

  2. REVIEW OF NRC APPROVED DIGITAL CONTROL SYSTEMS ANALYSIS

    International Nuclear Information System (INIS)

    Markman, D.W.

    1999-01-01

    Preliminary design concepts for the proposed Subsurface Repository at Yucca Mountain indicate extensive reliance on modern, computer-based, digital control technologies. The purpose of this analysis is to investigate the degree to which the U. S. Nuclear Regulatory Commission (NRC) has accepted and approved the use of digital control technology for safety-related applications within the nuclear power industry. This analysis reviews cases of existing digitally-based control systems that have been approved by the NRC. These cases can serve as precedence for using similar types of digitally-based control technologies within the Subsurface Repository. While it is anticipated that the Yucca Mountain Project (YMP) will not contain control systems as complex as those required for a nuclear power plant, the review of these existing NRC approved applications will provide the YMP with valuable insight into the NRCs review process and design expectations for safety-related digital control systems. According to the YMP Compliance Program Guidance, portions of various NUREGS, Regulatory Guidelines, and nuclear IEEE standards the nuclear power plant safety related concept would be applied to some of the designs on a case-by-case basis. This analysis will consider key design methods, capabilities, successes, and important limitations or problems of selected control systems that have been approved for use in the Nuclear Power industry. An additional purpose of this analysis is to provide background information in support of further development of design criteria for the YMP. The scope and primary objectives of this analysis are to: (1) Identify and research the extent and precedence of digital control and remotely operated systems approved by the NRC for the nuclear power industry. Help provide a basis for using and relying on digital technologies for nuclear related safety critical applications. (2) Identify the basic control architecture and methods of key digital control

  3. Digital signal processing in power system protection and control

    CERN Document Server

    Rebizant, Waldemar; Wiszniewski, Andrzej

    2011-01-01

    Digital Signal Processing in Power System Protection and Control bridges the gap between the theory of protection and control and the practical applications of protection equipment. Understanding how protection functions is crucial not only for equipment developers and manufacturers, but also for their users who need to install, set and operate the protection devices in an appropriate manner. After introductory chapters related to protection technology and functions, Digital Signal Processing in Power System Protection and Control presents the digital algorithms for signal filtering, followed

  4. Quasiinvariant Automatic Control Digital Systems of Inertia Objects

    OpenAIRE

    Lvov, Volodymyr; Andrieiev, Anatoliy

    2010-01-01

    The two-connected automatic control digital system (ACDS) and system of ACDS with combined control are examined. The two-connected and combined system of ACDS with work in the mode of tracking and stabilizing are analyzed. The discrete transfer function of two-connected and combined systems are obtained.

  5. Design type testing for digital instrumentation and control systems

    International Nuclear Information System (INIS)

    Bastl, W.; Mohns, G.

    1997-01-01

    The design type qualification of digital safety instrumentation and control is outlined. Experience shows that the concepts discussed, derived from codes, guidelines and standards, achieve useful results. It has likewise become clear that the systematics of design type qualification of the hardware components is also applicable to the software components. Design type qualification of the software, a premiere, could be performed unexpectedly smoothly. The hardware design type qualification proved that the hardware as a substrate of functionality and reliability is an issue that demands full attention, as compared to conventional systems. Another insight is that design qualification of digital instrumentation and control systems must include plant-independent systems tests. Digital instrumentation and control systems simply work very differently from conventional control systems, so that this testing modality is inevitable. (Orig./CB) [de

  6. Robust digital controllers for uncertain chaotic systems: A digital redesign approach

    Energy Technology Data Exchange (ETDEWEB)

    Ababneh, Mohammad [Department of Controls, FMC Kongsberg Subsea, FMC Energy Systems, Houston, TX 77067 (United States); Barajas-Ramirez, Juan-Gonzalo [CICESE, Depto. De Electronica y Telecomunicaciones, Ensenada, BC, 22860 (Mexico); Chen Guanrong [Centre for Chaos Control and Synchronization, Department of Electronic Engineering, City University of Hong Kong (China); Shieh, Leang S. [Department of Electrical and Computer Engineering, University of Houston, Houston, TX 77204-4005 (United States)

    2007-03-15

    In this paper, a new and systematic method for designing robust digital controllers for uncertain nonlinear systems with structured uncertainties is presented. In the proposed method, a controller is designed in terms of the optimal linear model representation of the nominal system around each operating point of the trajectory, while the uncertainties are decomposed such that the uncertain nonlinear system can be rewritten as a set of local linear models with disturbed inputs. Applying conventional robust control techniques, continuous-time robust controllers are first designed to eliminate the effects of the uncertainties on the underlying system. Then, a robust digital controller is obtained as the result of a digital redesign of the designed continuous-time robust controller using the state-matching technique. The effectiveness of the proposed controller design method is illustrated through some numerical examples on complex nonlinear systems--chaotic systems.

  7. Digital control in LLRF system for CYCIAE-100 cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Zhiguo, E-mail: bitbearAT@hotmail.com; Fu, Xiaoliang; Ji, Bin; Zhang, Tianjue; Wang, Chuan

    2016-05-21

    As a driven accelerator, the CYCIAE-100 cyclotron is designed by China Institute of Atomic Energy for the Beijing Radio Ion-beam Facility project. The cyclotron RF system is designed to use two RF power sources of 100 kW to drive two half-wavelength cavities respectively. Two Dee accelerating electrodes are kept separately from each other inside the cyclotron, while their accelerating voltages are maintained in phase by the efforts of LLRF control. An analog–digital hybrid LLRF system has been developed to achieve cavity tuning control, dee voltage amplitude and phase stabilization etc. The analog subsystems designs are focused on RF signal up/down conversion, tuning control, and dee voltage regulation. The digital system provides an RF signal source, aligns the cavity phases and maintains a Finite State Machine. The digital parts combine with the analog functions to provide the LLRF control. A brief system hardware introduction will be given in this paper, followed by the review of several major characteristics of the digital control in the 100 MeV cyclotron LLRF system. The commissioning is also introduced, and most of the optimization during the process was done by changing the digital parts.

  8. A high-performance digital control system for TCV

    International Nuclear Information System (INIS)

    Lister, J.B.; Dutch, M.J.; Milne, P.G.; Means, R.W.

    1997-10-01

    The TCV hybrid analogue-digital plasma control system has been superseded by a high performance Digital Plasma Control System, DPCS, made possible by recent advances in off the shelf technology. We discuss the basic requirements for such a control system and present the design and specifications which were laid down. The nominal and final performances are presented and the complete design is given in detail. The integration of the new system into the current operation of the TCV tokamak is described. The procurement of this system has required close collaboration between the end-users and two commercial suppliers with one of the latter taking full responsibility for the system integration. The impact of this approach on the design and commissioning costs for the TCV project is presented. New possibilities offered by this new system are discussed, including possible work relevant to ITER plasma control development. (author) 3 figs., 5 refs

  9. A high-performance digital control system for TCV

    Energy Technology Data Exchange (ETDEWEB)

    Lister, J.B.; Dutch, M.J. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP); Milne, P.G. [Pentland System Ltd., Livingstone (United Kingdom); Means, R.W. [HNC Software Inc., San Diego, CA (United States)

    1997-10-01

    The TCV hybrid analogue-digital plasma control system has been superseded by a high performance Digital Plasma Control System, DPCS, made possible by recent advances in off the shelf technology. We discuss the basic requirements for such a control system and present the design and specifications which were laid down. The nominal and final performances are presented and the complete design is given in detail. The integration of the new system into the current operation of the TCV tokamak is described. The procurement of this system has required close collaboration between the end-users and two commercial suppliers with one of the latter taking full responsibility for the system integration. The impact of this approach on the design and commissioning costs for the TCV project is presented. New possibilities offered by this new system are discussed, including possible work relevant to ITER plasma control development. (author) 3 figs., 5 refs.

  10. Digital Sliding Mode Control of Anti-Lock Braking System

    Directory of Open Access Journals (Sweden)

    MITIC, D. B.

    2013-02-01

    Full Text Available The control of anti-lock braking system is a great challenge, because of the nonlinear and complex characteristics of braking dynamics, unknown parameters of vehicle environment and system parameter variations. Using some of robust control methods, such as sliding mode control, can be a right solution for these problems. In this paper, we introduce a novel approach to design of ABS controllers, which is based on digital sliding mode control with only input/output measurements. The relay term of the proposed digital sliding mode control is filtered through digital integrator, reducing the chattering phenomenon in that way, and the additional signal of estimated modelling error is introduced into control algorithm to enhance the system steady-state accuracy. The given solution was verified in real experimental framework and the obtained results were compared with the results of implementation of two other digital sliding mode control algorithms. It is shown that it gives better system response, higher steady-state accuracy and smaller chattering.

  11. Reliability Estimation for Digital Instrument/Control System

    International Nuclear Information System (INIS)

    Yang, Yaguang; Sydnor, Russell

    2011-01-01

    Digital instrumentation and controls (DI and C) systems are widely adopted in various industries because of their flexibility and ability to implement various functions that can be used to automatically monitor, analyze, and control complicated systems. It is anticipated that the DI and C will replace the traditional analog instrumentation and controls (AI and C) systems in all future nuclear reactor designs. There is an increasing interest for reliability and risk analyses for safety critical DI and C systems in regulatory organizations, such as The United States Nuclear Regulatory Commission. Developing reliability models and reliability estimation methods for digital reactor control and protection systems will involve every part of the DI and C system, such as sensors, signal conditioning and processing components, transmission lines and digital communication systems, D/A and A/D converters, computer system, signal processing software, control and protection software, power supply system, and actuators. Some of these components are hardware, such as sensors and actuators, their failure mechanisms are well understood, and the traditional reliability model and estimation methods can be directly applied. But many of these components are firmware which has software embedded in the hardware, and software needs special consideration because its failure mechanism is unique, and the reliability estimation method for a software system will be different from the ones used for hardware systems. In this paper, we will propose a reliability estimation method for the entire DI and C system reliability using a recently developed software reliability estimation method and a traditional hardware reliability estimation method

  12. Reliability Estimation for Digital Instrument/Control System

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yaguang; Sydnor, Russell [U.S. Nuclear Regulatory Commission, Washington, D.C. (United States)

    2011-08-15

    Digital instrumentation and controls (DI and C) systems are widely adopted in various industries because of their flexibility and ability to implement various functions that can be used to automatically monitor, analyze, and control complicated systems. It is anticipated that the DI and C will replace the traditional analog instrumentation and controls (AI and C) systems in all future nuclear reactor designs. There is an increasing interest for reliability and risk analyses for safety critical DI and C systems in regulatory organizations, such as The United States Nuclear Regulatory Commission. Developing reliability models and reliability estimation methods for digital reactor control and protection systems will involve every part of the DI and C system, such as sensors, signal conditioning and processing components, transmission lines and digital communication systems, D/A and A/D converters, computer system, signal processing software, control and protection software, power supply system, and actuators. Some of these components are hardware, such as sensors and actuators, their failure mechanisms are well understood, and the traditional reliability model and estimation methods can be directly applied. But many of these components are firmware which has software embedded in the hardware, and software needs special consideration because its failure mechanism is unique, and the reliability estimation method for a software system will be different from the ones used for hardware systems. In this paper, we will propose a reliability estimation method for the entire DI and C system reliability using a recently developed software reliability estimation method and a traditional hardware reliability estimation method.

  13. Cyber secure systems approach for NPP digital control systems

    Energy Technology Data Exchange (ETDEWEB)

    McCreary, T. J.; Hsu, A. [HF Controls Corporation, 16650 Westgrove Drive, Addison, TX 75001 (United States)

    2006-07-01

    Whether fossil or nuclear power, the chief operations goal is to generate electricity. The heart of most plant operations is the I and C system. With the march towards open architecture, the I and C system is more vulnerable than ever to system security attacks (denial of service, virus attacks and others), thus jeopardizing plant operations. Plant staff must spend large amounts of time and money setting up and monitoring a variety of security strategies to counter the threats and actual attacks to the system. This time and money is a drain on the financial performance of a plant and distracts valuable operations resources from their real goals: product. The pendulum towards complete open architecture may have swung too far. Not all aspects of proprietary hardware and software are necessarily 'bad'. As the aging U.S. fleet of nuclear power plants starts to engage in replacing legacy control systems, and given the on-going (and legitimate) concern about the security of present digital control systems, decisions about how best to approach cyber security are vital to the specification and selection of control system vendors for these upgrades. The authors maintain that utilizing certain resources available in today's digital technology, plant control systems can be configured from the onset to be inherently safe, so that plant staff can concentrate on the operational issues of the plant. The authors postulate the concept of the plant I and C being bounded in a 'Cyber Security Zone' and present a design approach that can alleviate the concern and cost at the plant level of dealing with system security strategies. Present approaches through various IT cyber strategies, commercial software, and even postulated standards from various industry/trade organizations are almost entirely reactive and simply add to cost and complexity. This Cyber Security Zone design demonstrates protection from the four classes of cyber security attacks: 1)Threat from

  14. Cyber secure systems approach for NPP digital control systems

    International Nuclear Information System (INIS)

    McCreary, T. J.; Hsu, A.

    2006-01-01

    Whether fossil or nuclear power, the chief operations goal is to generate electricity. The heart of most plant operations is the I and C system. With the march towards open architecture, the I and C system is more vulnerable than ever to system security attacks (denial of service, virus attacks and others), thus jeopardizing plant operations. Plant staff must spend large amounts of time and money setting up and monitoring a variety of security strategies to counter the threats and actual attacks to the system. This time and money is a drain on the financial performance of a plant and distracts valuable operations resources from their real goals: product. The pendulum towards complete open architecture may have swung too far. Not all aspects of proprietary hardware and software are necessarily 'bad'. As the aging U.S. fleet of nuclear power plants starts to engage in replacing legacy control systems, and given the on-going (and legitimate) concern about the security of present digital control systems, decisions about how best to approach cyber security are vital to the specification and selection of control system vendors for these upgrades. The authors maintain that utilizing certain resources available in today's digital technology, plant control systems can be configured from the onset to be inherently safe, so that plant staff can concentrate on the operational issues of the plant. The authors postulate the concept of the plant I and C being bounded in a 'Cyber Security Zone' and present a design approach that can alleviate the concern and cost at the plant level of dealing with system security strategies. Present approaches through various IT cyber strategies, commercial software, and even postulated standards from various industry/trade organizations are almost entirely reactive and simply add to cost and complexity. This Cyber Security Zone design demonstrates protection from the four classes of cyber security attacks: 1)Threat from an intruder attempting to

  15. A multinode digital control system for 500 MWe PHWR

    Energy Technology Data Exchange (ETDEWEB)

    Patil, G N; Suresh Babu, R M; Jangra, L R; Das, Shantanu; Mallik, S B [Bhabha Atomic Research Centre, Bombay (India). Reactor Control Div.

    1994-12-31

    A fault tolerant distributed digital computer system for 500 MWe reactor power regulation is configured around standard microcomputer boards designed indigenously. The system is configured as functionally partitioned distributed control system having 8 nodes linked by high-speed dual redundant high-way. The paper gives the details of the configuration of system and how the features of fault-tolerance and fail-safeness are achieved through design. (author). 1 fig.

  16. Optical design of digital control systems

    CERN Document Server

    Tou, Julius T

    1963-01-01

    In this book, we study theoretical and practical aspects of computing methods for mathematical modelling of nonlinear systems. A number of computing techniques are considered, such as methods of operator approximation with any given accuracy; operator interpolation techniques including a non-Lagrange interpolation; methods of system representation subject to constraints associated with concepts of causality, memory and stationarity; methods of system representation with an accuracy that is the best within a given class of models; methods of covariance matrix estimation;methods for low-rank mat

  17. Evaluation and quality control of digital subtraction angiography systems

    International Nuclear Information System (INIS)

    Louisot, P.

    1986-04-01

    After reviewing the development of systems used in angiography, we rewind the medical interest and describe the steps of an angiographic examination. The following chapter is dedicated to the techniques used for the digitalization of video images. The components of the system involved in the image acquisition are thoroughly investigated in chapter 4. Then, we analyse the capabilities of the machines available in France in 1985. Chapter 6 is devoted to the criteria of quality in digital imaging. In order to assign qualitative values to the above criteria, we design a control procedure which is described in chapter 7. The procedure thus allows the estimate of the physical performances of angiographic digital subtraction systems [fr

  18. Digital electro-hydraulic control system for nuclear turbine

    International Nuclear Information System (INIS)

    Yokota, Yutaka; Tone, Youichi; Ozono, Jiro

    1985-01-01

    The unit capacity of steam turbines for nuclear power generation is very large, accordingly their unexpected stop disturbs power system, and the lowering of their capacity ratio exerts large influence on power generation cost. Therefore, very high reliability is required for turbine EHC controllers which directly control the turbines for nuclear power generation. In order to meet such requirement, Toshiba Corp. has developed high reliability type analog tripled turbine EHC controllers, and delivered them to No. 3 plant in the Fukushima No. 2 Nuclear Power Station and No. 1 plant in the Kashiwazaki Kariwa Nuclear Power Station, Tokyo Electric Power Co., Inc. At present, the trial operation is under way. The development of digital EHC controllers was begun in 1976, and through the digital EHC for a test turbine and that for a small turbine, the digital EHC controllers for the turbines for nuclear power generation were developed. In this paper, the function, constitution, features and maintenance of the digital tripled EHC controllers for the turbines for nuclear power generation, the application of new technology to them, and the confirmation of the control function by simulation are reported. (Kako, I.)

  19. Research methods of simulate digital compensators and autonomous control systems

    Directory of Open Access Journals (Sweden)

    V. S. Kudryashov

    2016-01-01

    Full Text Available The peculiarity of the present stage of development of the production is the need to control and regulate a large number of process parameters, the mutual influence on each other that when using single-circuit systems significantly reduces the quality of the transition process, resulting in significant costs of raw materials and energy, reduce the quality of the products. Using a stand-alone digital control system eliminates the correlation of technological parameters, to give the system the desired dynamic and static properties, improve the quality of regulation. However, the complexity of the configuration and implementation of procedures (modeling compensators autonomous systems of this type, associated with the need to perform a significant amount of complex analytic transformation significantly limit the scope of their application. In this regard, the approach based on the decompo sition proposed methods of calculation and simulation (realization, consisting in submitting elements autonomous control part digital control system in a series parallel connection. The above theoretical study carried out in a general way for any dimension systems. The results of computational experiments, obtained during the simulation of the four autonomous control systems, comparative analysis and conclusions on the effectiveness of the use of each of the methods. The results obtained can be used in the development of multi-dimensional process control systems.

  20. Digital control and data acquisition system for the QUIET experiment

    International Nuclear Information System (INIS)

    Bogdan, Mircea; Kapner, Dan; Samtleben, Dorothea; Vanderlinde, Keith

    2007-01-01

    We present the Digital Control and Data Acquisition System (DCDAQ) for Phase I of the Q/U Imaging Experiment (QUIET), arrays of 91 W-band and 19 Q-band receivers, placed on 1.4 m telescopes, in Chajnantor, Chile to measure the polarization of the cosmic microwave background. QUIET uses custom-built electronics boards that control and monitor its polarimeters. Each of these boards is digitally addressable, so that the DCDAQ can set and monitor any of the 1600 biases needed to operate the 91 receivers. The DCDAQ consists of a controller and up to 13 custom-made 32-channel ADC cards. Local FPGAs allow real-time data processing for each channel. This immediate data reduction is necessary, as it is planned to scale this technology beyond Phase I. The DCDAQ system is implemented with this future in mind and can easily be scaled to operate 1000 receivers

  1. Influence of discretization method on the digital control system performance

    Directory of Open Access Journals (Sweden)

    Futás József

    2003-12-01

    Full Text Available The design of control system can be divided into two steps. First the process or plant have to be convert into mathematical model form, so that its behavior can be analyzed. Then an appropriate controller have to be design in order to get the desired response of the controlled system. In the continuous time domain the system is represented by differential equations. Replacing a continuous system into discrete time form is always an approximation of the continuous system. The different discretization methods give different digital controller performance. The methods presented on the paper are Step Invariant or Zero Order Hold (ZOH Method, Matched Pole-Zero Method, Backward difference Method and Bilinear transformation. The above mentioned discretization methods are used in developing PI position controller of a dc motor. The motor model was converted by the ZOH method. The performances of the different methods are compared and the results are presented.

  2. Introduction of digital control

    International Nuclear Information System (INIS)

    Kim, Sang Jin

    1988-01-01

    This book is one of mechatronics series. It deals with digital control, which includes what is digital control?, display way of control system, output of primary system, secondary system like example of system and display way of the system, stabilizing of control system such as method to decide stability and system out of control, displaying equation of state into vector, good control such as the right characteristic, transient behavior and design of position control system using DC servo motor.

  3. A digital position-indication system for control rods

    International Nuclear Information System (INIS)

    Nishizawa, Yukio; Hayakawa, Toshifumi

    1979-01-01

    Systems that detect and indicate the position of the control rods that regulate the thermal output of a nuclear reactor play a particularly important role in monitoring its operational status. Conventionally, control rod position indication in pressurized water reactors has been of the analog type, utilizing the principle of the differential transformer. The present digital system was developed with the objective of achieving greater stability, greater accuracy, and higher reliability. The article gives a general description of the system and describes its advantages. (author)

  4. Retrofit of new digital control systems in existing power stations

    International Nuclear Information System (INIS)

    Smith, J.E.; Baird, C.F.

    1986-01-01

    With the notable exception of the Canadian CANDU nuclear power stations, little use has been made of digital control in North American nuclear stations. Recently, however, there has been renewed interest in such systems within the nuclear industry in response to demands for better ergonomics in control room design and the obsolescence of control equipment whose fundamental design has changed little in 20 yr. Early in 1985, Atomic Energy of Canada Limited was asked by New Brunswick Power to advise on the redesign of the control systems for two fossil-fired generating stations, Coleson Cove and Courtenay Bay Unit 4. Coleson Cove is to be converted from oil to coal firing with consequent extensive control system changes and Courtenay Bay Unit 4 required a low-cost solution to the problem of relocating its control room from the existing isolated location to the combined control center used by units 1, 2, and 3. In both cases, the recommended solution involves the retrofit of state-of-the-art digital control systems. Although the units involved are nonnuclear the experience is applicable

  5. A digital control and monitoring system for PWR waste-disposal systems

    International Nuclear Information System (INIS)

    Ueda, Toshiharu; Fuchigami, Kazuyuki; Shimozato, Masao; Takazawa, Kazuo

    1982-01-01

    Mitsubishi Electric has developed a digital control and monitoring system for PWR waste-disposal systems. This novel system has improved operability due to its automated operations and control, and integrated supervisory functions. The system includes other features to improve operability: sequence control by a control computer, direct-digital process control, integrated supervision of operation states by a supervisory computer and a high-speed dataway, and CRT interfacing between the computer and dataway. (author)

  6. Frequency to digital converter for IUAC Linac control system

    International Nuclear Information System (INIS)

    Jain, Mamta; Subramaiam, E.T.; Sahu, B.K.

    2015-01-01

    A frequency to digital converter CAMAC module has been designed and developed for LINAC control systems. This module is used to see the frequency difference of master clock and the resonator frequency digitally without using the oscilloscope. Later on this can be used for automatic tuning and locking of the cavities using piezoelectric actuator based tunner control. This module has eight independent channels to fulfill the need of all the eight cavities of the cryostat. A Schmitt trigger along with level converaccepts almost any form of pulse train, with 30 Vp-p. The time period is measured by counters clocked from a high resolution clock (10 MHz +/- 250 ps). The counter values are cross checked at both the input levels. Frequency is obtained from the computed time period by a special divisor core implemented inside the FPGA. The major task was the implementation of eight individual divisor cores and routing inside one Spartan 3s500E FPGA chip

  7. Nuclear reactor and production systems with digital controls

    International Nuclear Information System (INIS)

    Luger, P.P.

    1976-01-01

    Several digital sensing devices are described for use in automated production systems. The first described is for use in the automatic operation of a reactor. This device employs a binant electrometer using a quartz fiber mounted at one end but free to vibrate at the other in an AC field. The fiber oscillates if a charge is placed upon it. An optical slit replaces the ordinary eyepiece reticule scale. With the quartz fiber adjusted so its image is in focus at the optical slit, photoelectric signals are obtained at null charge on the fiber. The quartz fiber is repeatedly charged and allowed to discharge by collecting ions from a source under measurement. Each photoelectric signal causes a digital time reading to be taken. The time readings are used to evaluate the current due to the collected charge. The photoelectric signals, by feedback, also operate the electrometer for continuous or intermittent-continuous operation. Basically, the system is a current digitizer. Application is made to reactor monitoring and control as well as to other types of production systems. Finally, other types of sensing devices are also described and their use in automated controlled processes is shown. 3 claims, 19 figures

  8. Replacement of the complete control system of the NPP Oskarshamn 1 by digital distributed control system

    International Nuclear Information System (INIS)

    Berger, E.

    1998-01-01

    As part of an ongoing modernization program, the I and C system and the control room of Oskarshamn 1 will be upgraded by ABB using its 'Advant Power' range of digital, programmable process control system. Besides ensuring the higher level of safety that is demanded today, the new equipment provides the plant with an integrated system which will improve operator interaction with the plant and reduce the risk of human error. The newly installed DCS system will serve also as a platform for further improvements of the control room. This paper discusses Oskarshamn 1 exchange of the complete control system of a nuclear power plant, the technical solution and the time schedule. Oskarshamn 1 is the first nuclear power plant in Sweden. It is a boiling water reactor built between 1966 and 1971 by ABB ATOM in Sweden. According to the plant age the control system is relay-based, while instrumentation and analogue control is semiconductor-based. This makes maintenance expensive and even worse, makes extensions nearly impossible. According to the safety standards of the 1960s, there is no separation between safety and non safety control and no seismic qualification. To extend the life of this plant the owner has decided to improve the safety system as well as to replace the reactor protection system, the safety related control and the non safety related control by a state-of-the-art digital distributed control system from ABB. In March 1997, ABB got the order to replace the reactor protection system, the safety control system and to start the replacement of all control systems. The old control room has to be replaced by a new ergonomically design. Together with the exchange of the control system the safety features of the plant and the emergency power supply has to be extended. (author)

  9. Replacement of the complete control system of the NPP Oskarshamn 1 by digital distributed control system

    International Nuclear Information System (INIS)

    Berger, E.

    1998-01-01

    As part of an ongoing modernization program, Oskarshamn 1's I and C system and control room will be upgraded by ABB using its Advant Power range of digital, programmable process control system. Besides ensuring the higher level of safety that is demanded today, the new equipment provides the plant with an integrated system which will improve operator overview of operation and reduce risk of human error and serve as a platform for further improvements of the control room. This paper discusses in the example of Oskarshamn 1 how the complete control system of a nuclear power plant may be exchanged, the technical solution and the time schedule. Oskarshamn 1 is the first nuclear power plant in Sweden. It is a boiling water reactor built by ABB ATOM in Sweden between 1966 and 1971. According to this age the control system is semiconductor based and the reactor protection system is relays based. This makes the maintenance expensive and extensions nearly impossible. To extend the life period of this plant the owner has decided to improve the safety system and to replace the reactor protection system and safety related control and the non safety related control by a state of the art digital distributed control system of ABB. In March 1997 ABB got the order to replace the reactor protection system, the safety control system, to start the replacement of all control systems and to replace the old control room by a new ergonomically designed control room. Together with the exchange of the control system an enhancement of the safety system and of the emergency power supply will be implemented

  10. The reactor power control system based on digital control in nuclear power plant

    International Nuclear Information System (INIS)

    Liu Chong; Zhou Jianliang; Tan Ping

    2010-01-01

    The PLC (Programmable Logical Controller), digital communication and redundant techniques are applied in the rod control and position indication system(namely the reactor power control system) to perform the power control in the 300 MW reactor automatically and integrally in Qinshan Phase I project. This paper introduces the features, digital design methods of hardware of the instrumentation and control system (I and C) in the reactor power control. It is more convenient for the information exchange by human-machine interface (HMI), operation and maintenance, and the system reliability has been greatly improved after the project being reconstructed. (authors)

  11. Distributed digital real-time control system for TCV tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Le, H.B. [École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association EURATOM-Confédération Suisse, CH-1015 Lausanne (Switzerland); Felici, F. [Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Paley, J.I.; Duval, B.P.; Moret, J.-M.; Coda, S.; Sauter, O.; Fasel, D.; Marmillod, P. [École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association EURATOM-Confédération Suisse, CH-1015 Lausanne (Switzerland)

    2014-03-15

    Highlights: • A new distributed digital control system for the TCV tokamak has been commissioned. • Data is shared in real-time between all nodes using the reflective memory. • The customised Linux OS allows achieving deterministic and low latency behaviour. • The control algorithm design in Simulink together with the automatic code generation using Embedded Coder allow rapid algorithm development. • Controllers designed outside the TCV environment can be ported easily. • The previous control system functions have been emulated and improved. • New capabilities include MHD control, profile control, equilibrium reconstruction. - Abstract: A new digital feedback control system (named the SCD “Système de Contrôle Distribué”) has been developed, integrated and used successfully to control TCV (Tokamak à Configuration Variable) plasmas. The system is designed to be modular, distributed, and scalable, accommodating hundreds of diagnostic inputs and actuator outputs. With many more inputs and outputs available than previously possible, it offers the possibility to design advanced control algorithms with better knowledge of the plasma state and to coherently control all TCV actuators, including poloidal field (PF) coils, gas valves, the gyrotron powers and launcher angles of the electron cyclotron heating and current drive system (ECRH/ECCD) together with diagnostic triggering signals. The system consists of multiple nodes; each is a customised Linux desktop or embedded PC which may have local ADC and DAC cards. Each node is also connected to a memory network (reflective memory) providing a reliable, deterministic method of sharing memory between all nodes. Control algorithms are programmed as block diagrams in Matlab-Simulink providing a powerful environment for modelling and control design. The C code is generated automatically from the Simulink block diagram and compiled, with the Simulink Embedded Coder (SEC, formerly Real-Time Workshop Embedded

  12. MAPLE-X10 reactor digital control system

    International Nuclear Information System (INIS)

    Deverno, M.T.; Hinds, H.W.

    1991-10-01

    The MAPLE-X10 reactor, currently under construction at the Chalk River Laboratories of Atomic Energy of Canada Limited, is a 10 MW t , pool-type, light-water reactor. It will be used for radioisotope production and silicon neutron transmutation doping. The reactor is controlled by a Digital Control System (DCS) and protected against abnormal process events by two independent safety systems. The DCS is an integrated control system used to regulate the reactor power and process systems. The safety philosophy for the control system is to minimize unsafe events arising from system failures and operational errors. this is achieved through redundancy, fail-safe design, automatic fault detection, and the selection of highly reliable components. The DCS provides both computer-controlled reactor regulation from the shutdown state to full power and automated reactor shutdown if safe limits are exceeded or critical sensors malfunction. The use of commercially available hardware with enhanced quality assurance makes the system cost effective while providing a high degree of reliability

  13. The Digital Motion Control System for the Submillimeter Array Antennas

    Science.gov (United States)

    Hunter, T. R.; Wilson, R. W.; Kimberk, R.; Leiker, P. S.; Patel, N. A.; Blundell, R.; Christensen, R. D.; Diven, A. R.; Maute, J.; Plante, R. J.; Riddle, P.; Young, K. H.

    2013-09-01

    We describe the design and performance of the digital servo and motion control system for the 6-meter parabolic antennas of the Submillimeter Array (SMA) on Mauna Kea, Hawaii. The system is divided into three nested layers operating at a different, appropriate bandwidth. (1) A rack-mounted, real-time Unix system runs the position loop which reads the high resolution azimuth and elevation encoders and sends velocity and acceleration commands at 100 Hz to a custom-designed servo control board (SCB). (2) The microcontroller-based SCB reads the motor axis tachometers and implements the velocity loop by sending torque commands to the motor amplifiers at 558 Hz. (3) The motor amplifiers implement the torque loop by monitoring and sending current to the three-phase brushless drive motors at 20 kHz. The velocity loop uses a traditional proportional-integral-derivative (PID) control algorithm, while the position loop uses only a proportional term and implements a command shaper based on the Gauss error function. Calibration factors and software filters are applied to the tachometer feedback prior to the application of the servo gains in the torque computations. All of these parameters are remotely adjustable in the software. The three layers of the control system monitor each other and are capable of shutting down the system safely if a failure or anomaly occurs. The Unix system continuously relays the antenna status to the central observatory computer via reflective memory. In each antenna, a Palm Vx hand controller displays the complete system status and allows full local control of the drives in an intuitive touchscreen user interface. The hand controller can also be connected outside the cabin, a major convenience during the frequent reconfigurations of the interferometer. Excellent tracking performance ( 0.3‧‧ rms) is achieved with this system. It has been in reliable operation on 8 antennas for over 10 years and has required minimal maintenance.

  14. Development of Reactor Protection System (RPS) in Reactor Digital Instrumentation and Control System (ReDICS)

    International Nuclear Information System (INIS)

    Mohd Khairulezwan Abdul Manan; Mohd Sabri Minhat; Ridzuan Abdul Mutalib

    2013-01-01

    RTP Research Reactor are in the process upgraded from analogue control console system to a digital control console system . Upgrade process requires a statistical study to improve safety during reactor operation. RPS was developed to meet the needs of operational safety and at the same time comply with the guidelines set by the IAEA. RPS is in analog and hardware with industry standard interfaced with digital DAC (Data Acquisition and Control) and OWS (Operator Work Station). (author)

  15. Particle beam digital phase control system for COSY

    International Nuclear Information System (INIS)

    Schnase, A.

    1994-02-01

    Particle accelerators require that the orbit of the charged particles in the vacuum chamber is controlled to fulfil narrow limits. This is done by magnetic deflection systems and exactly adjusted rf-acceleration. Up to now the necessary control-functions were realised with analogue parts. This work describes a digital phase control system that works in real time and is used with the proton accelerator COSY. The physical design of the accelerator sets the accuracy-specifications of the revolution frequency (<1 Hz in the whole range from 400 kHz to 1.6 MHz), the phase-difference (<0.01 ), the signal-to-noise-ratio (<-60 dBc) and the update rate (<1 μs) of the parameters. In a typical operation the beam is first bunched and synchronised to the reference oscillator. After that the beam influences the rf-system with the help of charge detectors and now the rf-systems will be synchronised with the bunched beam. This control-loop is modelled and simulated with PSPICE. (orig.)

  16. Photovoltaic System Equipped with Digital Command Control and Acquisition

    Directory of Open Access Journals (Sweden)

    Khalil Kassmi

    2013-07-01

    Full Text Available In this paper, we present results concerning the design, the realization and the characterization of a photovoltaic system (PV, equipped with a digital controls: Power Point Tracking (MPPT, charge/discharge lead acid batteries, sun tracker and supervision. These different functions are performed with a microcontroller that has capabilities and functions to the reliability of PV systems (signal generation Pulses Width Modulation (PWM, speed etc.. Concerning the MPPT control operation, we improved the accuracy and reliability of research by improving the search algorithm “Hill Climbing” taking into account the optimal operation of PV panels depending on weather conditions (temperature and light.The experiment of each block shows that the MPPT control converges instantly the operating point of the PV panels around the maximum power point, independently of sudden changes of the illumination or the load. The control blocks charge/discharge battery and sun tracking show good control of charge/discharge lead acid batteries and the need of sun tracker to increase the power supplied by the PV panel. By using the improved MPPT control, loss of power supplied by the PV panels are very low (below 5%.

  17. Migration of Older to New Digital Control Systems in Nuclear Power Plant Main Control Rooms

    Energy Technology Data Exchange (ETDEWEB)

    Kovesdi, Casey Robert [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey Clark [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-04-01

    The United States (U.S.) Department of Energy (DOE) Office of Nuclear Energy (NE) has the primary mission to advance nuclear power by resolving socio-technical issues through research and development (R&D). One DOE-NE activity supporting this mission is the Light Water Reactor Sustainability (LWRS) program. LWRS has the overall objective to sustain the operation of existing commercial nuclear power plants (NPPs) through conducting R&D across multiple “pathways,” or R&D focus areas. The Advanced Instrumentation, Information, and Control (II&C) Systems Technologies pathway conducts targeted R&D to address aging and reliability concerns with the legacy instrumentation and control (I&C) and related information systems in operating U.S. NPPs. This work involves (1) ensuring that legacy analog II&C systems are not life-limiting issues for the LWR fleet, and (2) implementing digital II&C technology in a manner that enables broad innovation and business improvement in the NPP operating model. Under the LWRS Advanced II&C pathway, Human Factors experts at Idaho National Laboratory (INL) have been conducting R&D in support of NPP main control room (MCR) modernization activities. Work in prior years has focused on migrating analog I&C systems to new digital I&C systems (). In fiscal year 2016 (FY16), one new focus area for this research is migrating older digital I&C systems to new and advanced digital I&C systems. This report summarizes a plan for conducting a digital-to-digital migration of a legacy digital I&C system to a new digital I&C system in support of control room modernization activities.

  18. Migration of Older to New Digital Control Systems in Nuclear Power Plant Main Control Rooms

    International Nuclear Information System (INIS)

    Kovesdi, Casey Robert; Joe, Jeffrey Clark

    2016-01-01

    The United States (U.S.) Department of Energy (DOE) Office of Nuclear Energy (NE) has the primary mission to advance nuclear power by resolving socio-technical issues through research and development (R&D). One DOE-NE activity supporting this mission is the Light Water Reactor Sustainability (LWRS) program. LWRS has the overall objective to sustain the operation of existing commercial nuclear power plants (NPPs) through conducting R&D across multiple ''pathways,'' or R&D focus areas. The Advanced Instrumentation, Information, and Control (II&C) Systems Technologies pathway conducts targeted R&D to address aging and reliability concerns with the legacy instrumentation and control (I&C) and related information systems in operating U.S. NPPs. This work involves (1) ensuring that legacy analog II&C systems are not life-limiting issues for the LWR fleet, and (2) implementing digital II&C technology in a manner that enables broad innovation and business improvement in the NPP operating model. Under the LWRS Advanced II&C pathway, Human Factors experts at Idaho National Laboratory (INL) have been conducting R&D in support of NPP main control room (MCR) modernization activities. Work in prior years has focused on migrating analog I&C systems to new digital I&C systems (). In fiscal year 2016 (FY16), one new focus area for this research is migrating older digital I&C systems to new and advanced digital I&C systems. This report summarizes a plan for conducting a digital-to-digital migration of a legacy digital I&C system to a new digital I&C system in support of control room modernization activities.

  19. Implementation considerations for digital control systems in power plants: Final report

    International Nuclear Information System (INIS)

    Shah, S.C.; Lehman, L.L.; Sarchet, M.M.

    1988-09-01

    Conversion of nuclear power plants fron analog to digital control systems will require careful design, testing, and integration of the control algorithms, the software which implements the algorithms, the digital instrumentation, the digital communications network, and analog/digital device interfaces. Digital control systems are more flexible than their analog counterparts, and therefore greater attention must be paid by the customer to all stages of the control system design process. This flexibility also provides the framework for development of significant safety and reliability are inherant aspects of the chosen design processes. Digital control algorithms are capable of improving their performance by on-line self-tuning of the control parameters. It is therefore incumbant on system designers to choose self-tuning algorithms for power plant control. Implementation of these algorithms in software required a careful software design and development process to minimize errors in interpretation of the engineering design and prevent the inclusion of programming errors during software production. Digital control system and communications software must exhibit sufficient ''fault tolerance'' to maintain some level of safe plant operation or execute a safe plant shutdown in the event of both hard equipment failures and the appearance of software design faults. A number of standardized digital communications protocols are available to designers of digital control systems. These standardized digital communications protocols provide reliable fault tolerant communication between all digital elements of the plant control system and can be implemented redundantly to further enhance power plant operational safety. 5 refs., 11 figs., 1 tab

  20. Optimal sampling period of the digital control system for the nuclear power plant steam generator water level control

    International Nuclear Information System (INIS)

    Hur, Woo Sung; Seong, Poong Hyun

    1995-01-01

    A great effort has been made to improve the nuclear plant control system by use of digital technologies and a long term schedule for the control system upgrade has been prepared with an aim to implementation in the next generation nuclear plants. In case of digital control system, it is important to decide the sampling period for analysis and design of the system, because the performance and the stability of a digital control system depend on the value of the sampling period of the digital control system. There is, however, currently no systematic method used universally for determining the sampling period of the digital control system. Generally, a traditional way to select the sampling frequency is to use 20 to 30 times the bandwidth of the analog control system which has the same system configuration and parameters as the digital one. In this paper, a new method to select the sampling period is suggested which takes into account of the performance as well as the stability of the digital control system. By use of the Irving's model steam generator, the optimal sampling period of an assumptive digital control system for steam generator level control is estimated and is actually verified in the digital control simulation system for Kori-2 nuclear power plant steam generator level control. Consequently, we conclude the optimal sampling period of the digital control system for Kori-2 nuclear power plant steam generator level control is 1 second for all power ranges. 7 figs., 3 tabs., 8 refs. (Author)

  1. A Digital Motion Control System for Large Telescopes

    Science.gov (United States)

    Hunter, T. R.; Wilson, R. W.; Kimberk, R.; Leiker, P. S.

    2001-05-01

    We have designed and programmed a digital motion control system for large telescopes, in particular, the 6-meter antennas of the Submillimeter Array on Mauna Kea. The system consists of a single robust, high-reliability microcontroller board which implements a two-axis velocity servo while monitoring and responding to critical safety parameters. Excellent tracking performance has been achieved with this system (0.3 arcsecond RMS at sidereal rate). The 24x24 centimeter four-layer printed circuit board contains a multitude of hardware devices: 40 digital inputs (for limit switches and fault indicators), 32 digital outputs (to enable/disable motor amplifiers and brakes), a quad 22-bit ADC (to read the motor tachometers), four 16-bit DACs (that provide torque signals to the motor amplifiers), a 32-LED status panel, a serial port to the LynxOS PowerPC antenna computer (RS422/460kbps), a serial port to the Palm Vx handpaddle (RS232/115kbps), and serial links to the low-resolution absolute encoders on the azimuth and elevation axes. Each section of the board employs independent ground planes and power supplies, with optical isolation on all I/O channels. The processor is an Intel 80C196KC 16-bit microcontroller running at 20MHz on an 8-bit bus. This processor executes an interrupt-driven, scheduler-based software system written in C and assembled into an EPROM with user-accessible variables stored in NVSRAM. Under normal operation, velocity update requests arrive at 100Hz from the position-loop servo process running independently on the antenna computer. A variety of telescope safety checks are performed at 279Hz including routine servicing of a 6 millisecond watchdog timer. Additional ADCs onboard the microcontroller monitor the winding temperature and current in the brushless three-phase drive motors. The PID servo gains can be dynamically changed in software. Calibration factors and software filters can be applied to the tachometer readings prior to the application of

  2. Digital System Categorization Methodology to Support Integration of Digital Instrumentation and Control Models into PRAs

    International Nuclear Information System (INIS)

    Arndt, Steven A.

    2011-01-01

    It has been suggested that by categorizing the various digital systems used in safety critical applications in nuclear power plants, it would be possible to determine which systems should be modeled in the analysis of the larger plant wide PRA, at what level of detail the digital system should be modeled and using which methods. The research reported in this paper develops a categorization method using system attributes to permit a modeler to more effectively model the systems that will likely have the most critical contributions to the overall plant safety and to more effectively model system interactions for those digital systems where the interactions are most important to the overall accuracy and completeness of the plant PRA. The proposed methodology will categorize digital systems based on certain attributes of the systems themselves and how they will be used in the specific application. This will help determine what digital systems need to be modeled and at what level of detail, and can be used to guide PRA analysis and regulatory reviews. The three-attribute categorization strategy that was proposed by Arndt is used as the basis for the categorization methodology developed here. The first attribute, digital system complexity, is based on Type Il interactions defined by Aldemir and an overall digital system size and complexity index. The size and complexity index used are previously defined software complexity metrics. Potential sub-attributes of digital system complexity include, design complexity, software complexity, hardware complexity, system function complexity and testability. The second attribute, digital system interactions/inter-conductivity, is a combination of Rushby's coupling and Ademir's Type I interactions. Digital systems that are loosely coupled and/or have very few Type I interaction would not interact dynamically with the overall system and would have a low interactions/inter-conductivity score. Potential sub-attributes of digital system

  3. Digital System Categorization Methodology to Support Integration of Digital Instrumentation and Control Models into PRAs

    Energy Technology Data Exchange (ETDEWEB)

    Arndt, Steven A. [U.S. Nuclear Regulatory Commission, Washington D.C. (United States)

    2011-08-15

    It has been suggested that by categorizing the various digital systems used in safety critical applications in nuclear power plants, it would be possible to determine which systems should be modeled in the analysis of the larger plant wide PRA, at what level of detail the digital system should be modeled and using which methods. The research reported in this paper develops a categorization method using system attributes to permit a modeler to more effectively model the systems that will likely have the most critical contributions to the overall plant safety and to more effectively model system interactions for those digital systems where the interactions are most important to the overall accuracy and completeness of the plant PRA. The proposed methodology will categorize digital systems based on certain attributes of the systems themselves and how they will be used in the specific application. This will help determine what digital systems need to be modeled and at what level of detail, and can be used to guide PRA analysis and regulatory reviews. The three-attribute categorization strategy that was proposed by Arndt is used as the basis for the categorization methodology developed here. The first attribute, digital system complexity, is based on Type Il interactions defined by Aldemir and an overall digital system size and complexity index. The size and complexity index used are previously defined software complexity metrics. Potential sub-attributes of digital system complexity include, design complexity, software complexity, hardware complexity, system function complexity and testability. The second attribute, digital system interactions/inter-conductivity, is a combination of Rushby's coupling and Ademir's Type I interactions. Digital systems that are loosely coupled and/or have very few Type I interaction would not interact dynamically with the overall system and would have a low interactions/inter-conductivity score. Potential sub-attributes of

  4. An Investigation of Digital Instrumentation and Control System Failure Modes

    International Nuclear Information System (INIS)

    Korsah, Kofi; Cetiner, Mustafa Sacit; Muhlheim, Michael David; Poore, Willis P. III

    2010-01-01

    A study sponsored by the Nuclear Regulatory Commission study was conducted to investigate digital instrumentation and control (DI and C) systems and module-level failure modes using a number of databases both in the nuclear and non-nuclear industries. The objectives of the study were to obtain relevant operational experience data to identify generic DI and C system failure modes and failure mechanisms, and to obtain generic insights, with the intent of using results to establish a unified framework for categorizing failure modes and mechanisms. Of the seven databases studied, the Equipment Performance Information Exchange database was found to contain the most useful data relevant to the study. Even so, the general lack of quality relative to the objectives of the study did not allow the development of a unified framework for failure modes and mechanisms of nuclear I and C systems. However, an attempt was made to characterize all the failure modes observed (i.e., without regard to the type of I and C equipment under consideration) into common categories. It was found that all the failure modes identified could be characterized as (a) detectable/preventable before failures, (b) age-related failures, (c) random failures, (d) random/sudden failures, or (e) intermittent failures. The percentage of failure modes characterized as (a) was significant, implying that a significant reduction in system failures could be achieved through improved online monitoring, exhaustive testing prior to installation, adequate configuration control or verification and validation, etc.

  5. Control system of digital x-ray systems by quality parameters

    International Nuclear Information System (INIS)

    Balashov, S.V.; Kovalenko, Yu.N.

    2013-01-01

    The paper proposed a control system of X-ray digital equipment on quality indicators. Two basic parameters were determined: image quality and patients' radiation load. A method for monitoring these indicators is proposed. The criterion of equipment suitability is to obtain control digital X-ray images of diagnostically acceptable quality at a fixed low entrance dose in the plane of the digital detector. It is shown that the control system of X-ray digital equipment based on indicators of quality is the most appropriate in situations of deficit of financial resources, since minimizing the costs for the purchase and running of control systems, does not require highly skilled technical personnel, and reduces the duration of the equipment inspection. (authors)

  6. Upgrading the Reactor Power Control Concept with a Modern Digital Control System

    International Nuclear Information System (INIS)

    Laengle, M.; Schildheuer, R.

    2011-01-01

    Within the framework of a retrofit project, a reactor power instrumentation and control system (REALL) - consisting of a limiting system and the respective reactor control systems - was retrofitted and modernized in a 1450-MW-nuclear-power-plant in Baden-Wuerttemberg. The REALL process control functions were implemented within a modern and completely digitized control system that has been designed for use in safety I and C applications. Along with the installation of the digital control system, the associated hardware was adapted to today's state of the art. At the same time, the given potential for improvement, as revealed during the plant's operation so far, was taken into account in the programming. In order to provide for transparent and quality-assured project management, the implementation was based on a stage plan consisting of several steps, along with specific milestones. Final commissioning of the modern digital control system took place during the 2008 plant overhaul. Despite the complex commissioning procedure, it was possible to avoid a major prolongation of the plant's downtime and to keep within a rough 4-week timeframe that had originally been defined for the plant overhaul to adequate structuring of the project, goal-oriented implementation of preparatory infrastructural measures and adequate scheduling of the coordinated activities of the installation and commissioning teams entrusted with the commissioning of the digital control system during the overhaul activities. (author)

  7. Digital redesign of anti-wind-up controller for cascaded analog system.

    Science.gov (United States)

    Chen, Y S; Tsai, J S H; Shieh, L S; Moussighi, M M

    2003-01-01

    The cascaded conventional anti-wind-up (CAW) design method for integral controller is discussed. Then, the prediction-based digital redesign methodology is utilized to find the new pulse amplitude modulated (PAM) digital controller for effective digital control of the analog plant with input saturation constraint. The desired digital controller is determined from existing or pre-designed CAW analog controller. The proposed method provides a novel methodology for indirect digital design of a continuous-time unity output-feedback system with a cascaded analog controller as in the case of PID controllers for industrial control processes with the presence of actuator saturations. It enables us to implement an existing or pre-designed cascaded CAW analog controller via a digital controller effectively.

  8. Formulation of a strategy for monitoring control integrity in critical digital control systems

    Science.gov (United States)

    Belcastro, Celeste M.; Fischl, Robert; Kam, Moshe

    1991-01-01

    Advanced aircraft will require flight critical computer systems for stability augmentation as well as guidance and control that must perform reliably in adverse, as well as nominal, operating environments. Digital system upset is a functional error mode that can occur in electromagnetically harsh environments, involves no component damage, can occur simultaneously in all channels of a redundant control computer, and is software dependent. A strategy is presented for dynamic upset detection to be used in the evaluation of critical digital controllers during the design and/or validation phases of development. Critical controllers must be able to be used in adverse environments that result from disturbances caused by an electromagnetic source such as lightning, high intensity radiated field (HIRF), and nuclear electromagnetic pulses (NEMP). The upset detection strategy presented provides dynamic monitoring of a given control computer for degraded functional integrity that can result from redundancy management errors and control command calculation error that could occur in an electromagnetically harsh operating environment. The use is discussed of Kalman filtering, data fusion, and decision theory in monitoring a given digital controller for control calculation errors, redundancy management errors, and control effectiveness.

  9. Analog and digital appliance technology for the control and monitoring of space HVAC systems

    Energy Technology Data Exchange (ETDEWEB)

    Gyoeri, M

    1987-01-01

    Both analog and digital devices are expected to meet the required control functions. The analog control device meets this function by way of a complicated circuitry and wiring technology of varying sophistication. In the digital control by a preprogrammed microprocessor. Digital technology allows to use the copied programme in different devices. Any change in the control of a system can be implemented and met by a programme change in digital technology. In analog technology, this change involves a change in wiring. (orig./HW).

  10. Addressing selected problems of the modelling of digital control systems

    International Nuclear Information System (INIS)

    Sedlak, J.

    2004-12-01

    The introduction of digital systems to practical activities at nuclear power plants brings about new requirements for their modelling for the purposes of reliability analyses required for plant licensing as well as for inclusion into PSA studies and subsequent use in applications for the assessment of events, limits and conditions, and risk monitoring. It is very important to assess, both qualitatively and quantitatively, the effect of this change on operational safety. The report describes selected specific features of reliability analysis of digital system and recommends methodological procedures. The chapters of the report are as follows: (1) Flexibility and multifunctionality of the system. (2) General framework of reliability analyses (Understanding the system; Qualitative analysis; Quantitative analysis; Assessment of results, comparison against criteria; Documenting system reliability analyses; Asking for comments and their evaluation); and (3) Suitable reliability models (Reliability models of basic events; Monitored components with repair immediately following defect or failure; Periodically tested components; Constant unavailability (probability of failure to demand); Application of reliability models for electronic components; Example of failure rate decomposition; Example modified for diagnosis successfulness; Transfer of reliability analyses to PSA; Common cause failures - CCF; Software backup and CCF type failures, software versus hardware). (P.A.)

  11. Digital, remote control system for a 2-MW research reactor

    International Nuclear Information System (INIS)

    Battle, R.E.; Corbett, G.K.

    1988-01-01

    A fault-tolerant programmable logic controller (PLC) and operator workstations have been programmed to replace the hard-wired relay control system in the 2-MW Bulk Shielding Reactor (BSR) at Oak Ridge National Laboratory. In addition to the PLC and remote and local operator workstations, auxiliary systems for remote operation include a video system, an intercom system, and a fiber optic communication system. The remote control station, located at the High Flux Isotope Reactor 2.5 km from the BSR, has the capability of rector startup and power control. The system was designed with reliability and fail-safe features as important considerations. 4 refs., 3 figs

  12. Comparison of Failure Analysis and Operating Experiences of Digital Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Chan; Shin, Tae Young [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2014-08-15

    This study focuses on digital control systems that have the same functions but different designs. Some differences and common points between these two digital control systems are analyzed in terms of vulnerabilities in plant operation. In addition, this study confirms why unexpected outcomes can occur through a comparison of the system failure experiences with the analytic results of FMEA and FTA. This evaluation demonstrates that the digital system may have vulnerable components whose single failures can cause plant transients even if the system has a redundant structure according to its system design.

  13. A quality control system for digital elevation data

    Science.gov (United States)

    Knudsen, Thomas; Kokkendorf, Simon; Flatman, Andrew; Nielsen, Thorbjørn; Rosenkranz, Brigitte; Keller, Kristian

    2015-04-01

    In connection with the introduction of a new version of the Danish national coverage Digital Elevation Model (DK-DEM), the Danish Geodata Agency has developed a comprehensive quality control (QC) and metadata production (MP) system for LiDAR point cloud data. The architecture of the system reflects its origin in a national mapping organization where raw data deliveries are typically outsourced to external suppliers. It also reflects a design decision of aiming at, whenever conceivable, doing full spatial coverage tests, rather than scattered sample checks. Hence, the QC procedure is split in two phases: A reception phase and an acceptance phase. The primary aim of the reception phase is to do a quick assessment of things that can typically go wrong, and which are relatively simple to check: Data coverage, data density, strip adjustment. If a data delivery passes the reception phase, the QC continues with the acceptance phase, which checks five different aspects of the point cloud data: Vertical accuracy Vertical precision Horizontal accuracy Horizontal precision Point classification correctness The vertical descriptors are comparatively simple to measure: The vertical accuracy is checked by direct comparison with previously surveyed patches. The vertical precision is derived from the observed variance on well defined flat surface patches. These patches are automatically derived from the road centerlines registered in FOT, the official Danish map data base. The horizontal descriptors are less straightforward to measure, since potential reference material for direct comparison is typically expected to be less accurate than the LiDAR data. The solution selected is to compare photogrammetrically derived roof centerlines from FOT with LiDAR derived roof centerlines. These are constructed by taking the 3D Hough transform of a point cloud patch defined by the photogrammetrical roof polygon. The LiDAR derived roof centerline is then the intersection line of the two primary

  14. Fast digital feedback control systems for accelerator RF system using FPGA

    International Nuclear Information System (INIS)

    Bagduwal, Pritam Singh; Sharma, Dheeraj; Tiwari, Nitesh; Lad, M.; Hannurkar, P.R.

    2012-01-01

    Feedback control system plays important role for proper injection and acceleration of beam in particle accelerators by providing the required amplitude and phase stability of RF fields in accelerating structures. Advancement in the field of digital technology enables us to develop fast digital feedback control system for RF applications. Digital Low Level RF (LLRF) system offers the inherent advantages of Digital System like flexibility, adaptability, good repeatability and reduced long time drift errors compared to analog system. To implement the feedback control algorithm, I/Q control scheme is used. By properly sampling the down converted IF signal using fast ADC we get accurate feedback signal and also eliminates the need of two separate detectors for amplitude and phase detection. Controller is implemented in Vertex-4 FPGA. Codes for control algorithms which controls the amplitude and phase in all four quadrants with good accuracy are written in the VHDL. I/Q modulator works as common actuator for both amplitude and phase correction. Synchronization between RF, LO and ADC clock is indispensable and has been achieved by deriving the clock and LO signal from RF signal itself. Control system has been successfully tested in lab with phase and amplitude stability better then ±1% and ±1° respectively. High frequency RF signal is down converted to IF using the super heterodyne technique. Super heterodyne principal not only brings the RF signal to the Low IF frequency at which it can be easily processed but also enables us to use the same hardware and software for other RF frequencies with some minor modification. (author)

  15. Implementation of digital control and protection systems of China advanced research reactor

    International Nuclear Information System (INIS)

    Zeng Hai; Jin Huajin; Xu Qiguo; Zhang Mingkui

    2005-01-01

    China Advanced Research Reactor (CARR), a reactor of the 21st century with high performance is being constructed in China. The requirements of reliability and stability on the control and protection (c and p) system are the main points raised. Especially, with the development of digital technology, the c and p system of CARR is demanded to match the trend of digitization in the field of reactor control. The c and p system, including reactor protection system, reactor monitoring and control system, reactor power regulating system, and the mitigation system for ATWS (Anticipate Transient Without Scram), adopts digital technology, and the digital display screen will replace the analog panels in the main control room. The c and p system of CARR adopts redundant technology with 2 or 3 redundant channels to improve the system reliability. The 10/100 Mbps self-adaptive redundant optic fiber industry Ethernet ring network is used to interlink operator workstations, supervisor workstation, and I/O control stations. Commercial grade equipment with mature experience in industrial application are applied to the c and p system of CARR, which have high reliability, good interchangeability, and is easily purchased, the software-developing tools fully match the international industry standards. The realization of digital c and p system of CARR will promote the progress of digital control technology for reactors in China, and certainly become a technical basic platform for developing informational and intelligent reactors in China. (authors)

  16. Cyber and physical equipment digital control system in Industry 4.0 item designing company

    Science.gov (United States)

    Gurjanov, A. V.; Zakoldaev, D. A.; Shukalov, A. V.; Zharinov, I. O.

    2018-05-01

    The problem of organization of digital control of the item designing company equipped with cyber and physical systems is being studied. A scheme of cyber and physical systems and personnel interaction in the Industry 4.0 smart factory company is presented. A scheme of assembly units transportation in the Industry 4.0 smart factory company is provided. A scheme of digital control system in the Industry 4.0 smart factory company is given.

  17. The test and control system for high performance digital power supplies of SSRF

    International Nuclear Information System (INIS)

    Tang Junlong; Li Deming; Shen Tianjian

    2009-01-01

    A test and control system was designed to evaluate performance of the digital power supplies for SSRF. The software of serial communication (RS-232) and Ethernet interface was developed with Lab VIEW. The system can perform functions of instrument and power supply control, data acquisition and display, and store data for 24 h. LAN users can access the system and acquire data conveniently. The data are stored in Excel for analysis and establishment of database of digital PS in the future. (authors)

  18. Selecting a software development methodology. [of digital flight control systems

    Science.gov (United States)

    Jones, R. E.

    1981-01-01

    The state of the art analytical techniques for the development and verification of digital flight control software is studied and a practical designer oriented development and verification methodology is produced. The effectiveness of the analytic techniques chosen for the development and verification methodology are assessed both technically and financially. Technical assessments analyze the error preventing and detecting capabilities of the chosen technique in all of the pertinent software development phases. Financial assessments describe the cost impact of using the techniques, specifically, the cost of implementing and applying the techniques as well as the relizable cost savings. Both the technical and financial assessment are quantitative where possible. In the case of techniques which cannot be quantitatively assessed, qualitative judgements are expressed about the effectiveness and cost of the techniques. The reasons why quantitative assessments are not possible will be documented.

  19. A digital closed loop control system for automatic phase locking of superconducting cavities of IUAC Linac

    International Nuclear Information System (INIS)

    Dutt, R.N.; Rai, A.; Pandey, A.; Sahu, B.K.; Patra, P.; Karmakar, J.; Chaudhari, G.K.; Mathur, Y.; Ghosh, S.; Kanjilal, D.

    2013-01-01

    A closed loop digital control system has been designed and tested to automate the tuning process of superconducting resonators of LINAC at Inter-University Accelerator Centre, New Delhi. The mechanism controls the proportional valves of the He gas based pneumatic tuner in response to the phase and frequency errors of the cavity RF field. The main RF phase lock loop (PLL) is automatically closed once the resonant frequency is within locking range of the resonator PLL. The digital control scheme was successfully tested on few resonators of LINAC cryostat 1. A high stability of phase lock was observed. The details of the digital automation system are presented in the paper. (author)

  20. Method and system for redundancy management of distributed and recoverable digital control system

    Science.gov (United States)

    Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)

    2012-01-01

    A method and system for redundancy management is provided for a distributed and recoverable digital control system. The method uses unique redundancy management techniques to achieve recovery and restoration of redundant elements to full operation in an asynchronous environment. The system includes a first computing unit comprising a pair of redundant computational lanes for generating redundant control commands. One or more internal monitors detect data errors in the control commands, and provide a recovery trigger to the first computing unit. A second redundant computing unit provides the same features as the first computing unit. A first actuator control unit is configured to provide blending and monitoring of the control commands from the first and second computing units, and to provide a recovery trigger to each of the first and second computing units. A second actuator control unit provides the same features as the first actuator control unit.

  1. Design and Evaluation of a Digital Flight Control System for the FROG Unmanned Aerial Vehicle

    National Research Council Canada - National Science Library

    Flood, Christopher

    2001-01-01

    .... This autopilot imposed significant limitations on the responsiveness of the FROG. This project developed and tested an off board digital flight control system for use in lieu of the previous electromechanical device...

  2. Digital low level rf control system with four different intermediate frequencies for the International Linear Collider

    Science.gov (United States)

    Wibowo, Sigit Basuki; Matsumoto, Toshihiro; Michizono, Shinichiro; Miura, Takako; Qiu, Feng; Liu, Na

    2017-09-01

    A field programmable gate array-based digital low level rf (LLRF) control system will be used in the International Linear Collider (ILC) in order to satisfy the rf stability requirements. The digital LLRF control system with four different intermediate frequencies has been developed to decrease the required number of analog-to-digital converters in this system. The proof of concept of this technique was demonstrated at the Superconducting RF Test Facility in the High Energy Accelerator Research Organization, Japan. The amplitude and phase stability has fulfilled the ILC requirements.

  3. A digital signal processor based rf control system for the TRIUMF ISAC RFQ prototype

    International Nuclear Information System (INIS)

    Fong, K.; Fang, S.; Laverty, M.

    1996-01-01

    A stand alone digital signal processor is used to control the RFQ prototype in the TRIUMF ISAC development program. The advantage of a digital control system over the traditional analogue system is that it offers the higher degree of flexibility necessary for a development system. For this application the system is designed to have the outward appearance of an analogue system, and uses dials, knobs, and switches as the operator interface. The digital signal processor is used as a feedback controller during CW rf operation, with the feedback gain parameters continually adjustable. It is also able to perform the same regulation during pulsed operation, with additional feedforward compensation for initial pulse on duration. Using a low cost analogue-to-digital converter with a sample rate of 100 kHz, a regulation bandwidth of 10 kHz is achieved. (author)

  4. Digital and analog communication systems

    Science.gov (United States)

    Shanmugam, K. S.

    1979-01-01

    The book presents an introductory treatment of digital and analog communication systems with emphasis on digital systems. Attention is given to the following topics: systems and signal analysis, random signal theory, information and channel capacity, baseband data transmission, analog signal transmission, noise in analog communication systems, digital carrier modulation schemes, error control coding, and the digital transmission of analog signals.

  5. Digital control system of a steam generator water level by LQG optimal method

    International Nuclear Information System (INIS)

    Lee, Yoon Joon

    1993-01-01

    A digital control system for the steam generator water level control is developed using LQG optimal design method. To describe the more realistic situaton, a feedwater valve actuator is assumed to be of the first order lagger and is included in the overall control system. By composing the digital control circuit in such a way that the overall control system consists of two sub-systems of feedwater station and feedback loop digital controller, the design procedure is divided into two independent steps. The feedwater station system is described in the error dynamics of an ordinary regulator system. The optimal gains are obtained by LQ method which imposes the constraints of the feedwater valve motion as well as on the output deviations. Developed also is a Kalman observer on account of the flow measurement uncertainty at low power. Then a digital controller on the feedback loop is designed so that the system maintains the same stability margins for all power ranges. The simulation results show thst the optimal digital system has a good control characteristics despite the adverse dynamics of a steam generator at low power. (Author)

  6. Application of discrete function and software control flow to dependability assessment of embedded digital system

    International Nuclear Information System (INIS)

    Choi, Jong Gyun; Seong, Poong Hyun

    2001-01-01

    This article describes a combinatorial model for estimating the reliability of the embedded digital system by means of discrete function theory and software control flow. This model includes a coverage model for fault processing mechanisms implemented in digital system. Furthermore, the model considers the interaction between hardware and software. The fault processing mechanisms make it difficult for many types of components in digital system to be treated as binary state, good or bad. The discrete function theory provides a complete analysis of multi-state system as which the digital system can be regarded Through adaptation software control flow to discrete function theory, the HW/SW interaction is considered for estimation of the reliability of digital system. Using this model, we predict the reliability of one board controller in a digital system, Interposing Logic System(ILS), which is installed in YGN nuclear power units 3 and 4. Since the proposed model is general combinatinal model, the simplification of this model becomes a conservative model that treats the system as binary state. Moreover, if information for coverage factor of fault tolerance mechanisms implemented in system through fault injection experiment is obtained, this model can consider detailed interaction of system components

  7. Digital remote control system for power supplies of particle channel magnetooptical elements

    International Nuclear Information System (INIS)

    Vetrov, P.B.; Ermolina, G.P.; Kuznetsov, V.S.; Mojbenko, A.N.

    1986-01-01

    Current control of magnetooptical elements of accelerator particle channels is based on control of reference voltage of current stabilizers. Advent of industrial multidigit (12 bits) integral analog-to-digital converters permitted to develop simple digital sources of reference voltage. A digital control system of 30 spatially remoted power supplies of magnetooptical elements of particle channels on the basis of the ''Elektronika-60'' microcomputer is described. The microcomputer is connected by the standard communication line (20 mA) with the SM-4 computer. The ''Summa'' crate is connected with the microcomputer through the branch driver. Digit data are transmitted by the multibranch trunk of sequential communication (Manchester-2 code) at the rate of 0.5 Mband. Feedback was realized by connection of analog signals through the distributed commutator to the measuring line with a digital voltmeter

  8. Monitoring system and methods for a distributed and recoverable digital control system

    Science.gov (United States)

    Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)

    2010-01-01

    A monitoring system and methods are provided for a distributed and recoverable digital control system. The monitoring system generally comprises two independent monitoring planes within the control system. The first monitoring plane is internal to the computing units in the control system, and the second monitoring plane is external to the computing units. The internal first monitoring plane includes two in-line monitors. The first internal monitor is a self-checking, lock-step-processing monitor with integrated rapid recovery capability. The second internal monitor includes one or more reasonableness monitors, which compare actual effector position with commanded effector position. The external second monitor plane includes two monitors. The first external monitor includes a pre-recovery computing monitor, and the second external monitor includes a post recovery computing monitor. Various methods for implementing the monitoring functions are also disclosed.

  9. PS BOOSTER BEAM TESTS OF THE NEW DIGITAL BEAM CONTROL SYSTEM FOR LEIR

    CERN Document Server

    Angoletta, Maria Elena; Bento, J; De Long, J H; Findlay, A; Matuszkiewicz, P; Pedersen, F; Salom-Sarasqueta, A; CERN. Geneva. AB Department

    2005-01-01

    We have been developing a scaled-down prototype of the new digital beam control and cavity servoing system for CERN’s Low Energy Ion Ring (LEIR) slated for commissioning in 2005. The system’s hardware and software, developed as part of a CERN-BNL collaboration, are based on new all-digital technology already deployed at BNL's AGS Booster. The system relies on VME modules, carrying Digital Signal Processors (DSPs) as well as Field Programmable Gate Arrays (FPGAs), and daughter cards. New concepts deployed include software implementation, through DSPs & FPGAs, of functions traditionally executed by analogue hardware, such as reference-functions and timings generation. Additionally, a user-selectable digital data acquisition functionality provides diagnostic and troubleshoot access points, a new feature which is very useful in a digital system. The scaled-down prototype implements frequency program, radial steering, phase and radial loops capabilities and it has been tested in CERN's PS Booster (PSB) dur...

  10. Test and control computer user's guide for a digital beam former test system

    Science.gov (United States)

    Alexovich, Robert E.; Mallasch, Paul G.

    1992-01-01

    A Digital Beam Former Test System was developed to determine the effects of noise, interferers and distortions, and digital implementations of beam forming as applied to the Tracking and Data Relay Satellite 2 (TDRS 2) architectures. The investigation of digital beam forming with application to TDRS 2 architectures, as described in TDRS 2 advanced concept design studies, was conducted by the NASA/Lewis Research Center for NASA/Goddard Space Flight Center. A Test and Control Computer (TCC) was used as the main controlling element of the digital Beam Former Test System. The Test and Control Computer User's Guide for a Digital Beam Former Test System provides an organized description of the Digital Beam Former Test System commands. It is written for users who wish to conduct tests of the Digital Beam forming Test processor using the TCC. The document describes the function, use, and syntax of the TCC commands available to the user while summarizing and demonstrating the use of the commands wtihin DOS batch files.

  11. Analysis and improvement of digital control stability for master-slave manipulator system

    International Nuclear Information System (INIS)

    Yoshida, Koichi; Yabuta, Tetsuro

    1992-01-01

    Some bilateral controls of master-slave system have been designed, which can realize high-fidelity telemanipulation as if the operator were manipulating the object directly. While usual robot systems are controlled by software-servo system using digital computer, little work has been published on design and analysis for digital control of these systems, which must consider time-delay of sensor signals and zero order hold effect of command signals on actuators. This paper presents a digital control analysis for single degree of freedom master-slave system including impedance models of both the human operator and the task object, which clarifies some index for the stability. The stability result shows a virtual master-slave system concepts, which improve the digital control stability. We first analyze a dynamic control method of master-slave system in discrete-time system for the stability problem, which can realize high-fidelity telemanipulation in the continuous-time. Secondly, using the results of the stability analysis, the robust control scheme for master-slave system is proposed, and the validity of this scheme is finally confirmed by the simulation. Consequently, it would be considered that any combination of master and slave modules with dynamic model of these manipulators is possible to construct the stable master-slave system. (author)

  12. Implementation of a digital feedwater control system at Dresden Nuclear Power Plant, Units 2 and 3: Final report

    International Nuclear Information System (INIS)

    Zapotocky, A.; Popovic, J.R.; Fournier, R.D.

    1988-12-01

    This report describes the Digital Feedwater Control System Implementation at the Dresden 2 or 3 Units of the BWR Nuclear Power Plant owned by the Commonwealth Edison Company. The digital system has been operational in Unit 3 since August 1986, and in Unit 2 since April 1987. The Bailey Control's Network 90 based digital control system replaced the obsolete GE/MAC 5000 analog control system in the reactor feedwater control loop as a ''like-for-like'' replacement. Operational experience from the Digital Feedwater Control installations has been good and the system demonstrated better performance than the old analog systems. 14 refs., 15 figs., 17 tabs

  13. A Mixed-Reality Environment for Digital Control Systems

    Directory of Open Access Journals (Sweden)

    Heinz-Dietrich Wuttke

    2006-04-01

    Full Text Available Learning the design of control systems requires not only deep theoretical but also practical experience that can be get in laboratory work. Goal of the projects “JGIFT” and “FIPS” - created by members of the Institute of Theoretical and Technical Computer Science of the Technical University of Ilmenau - is to examine and implement new techniques for a development and training system based on Finite State Machines (FSM. In our contribution we would like to present means and methods required for providing this tool set web wide for a large user base and independent from the operating system.

  14. LQR Feedback Control Development for Wind Turbines Featuring a Digital Fluid Power Transmission System

    DEFF Research Database (Denmark)

    Pedersen, Niels Henrik; Johansen, Per; Andersen, Torben O.

    2016-01-01

    with a DFP motor, which has been combined with the NREL 5-MW reference wind turbine model. A classical variable speed control strategy for wind speeds below rated is proposed for the turbine, where the pump displacement is fixed and the digital motor displacement is varied for pressure control. The digital...... for such digital systems are complicated by its non-smooth behavior. In this paper a control design approach for a digital displacement machine® is proposed and a performance analysis of a wind turbine using a DFP transmission is presented. The performance evaluation is based on a dynamic model of the transmission...... invariant model. Using full-field flow wind profiles as input, the design approach and control performance is verified by simulation in the dynamic model of the wind turbine featuring the DFP transmission. Additionally, the performance is compared to that of the conventional NREL reference turbine...

  15. Application of digital control systems in nuclear power plants

    International Nuclear Information System (INIS)

    Keiper, J.T.

    1993-01-01

    This paper describes a sampling of recent digital applications, both safety related and non-safety related, in four nuclear power plants and discusses a few of the unique application experiences. Each application accrues unique benefits, but also poses unique problems. A few of the benefits and problems are discussed

  16. Digital PI-PD controller design for arbitrary order systems: Dominant pole placement approach.

    Science.gov (United States)

    Dincel, Emre; Söylemez, Mehmet Turan

    2018-05-02

    In this paper, a digital PI-PD controller design method is proposed for arbitrary order systems with or without time-delay to achieve desired transient response in the closed-loop via dominant pole placement approach. The digital PI-PD controller design problem is solved by converting the original problem to the digital PID controller design problem. Firstly, parametrization of the digital PID controllers which assign dominant poles to desired location is done. After that the subset of digital PID controller parameters in which the remaining poles are located away from the dominant pole pair is found via Chebyshev polynomials. The obtained PID controller parameters are then transformed into the PI-PD controller parameters by considering the closed-loop controller zero and the design is completed. Success of the proposed design method is firstly demonstrated on an example transfer function and compared with the well-known PID controller methods from the literature through simulations. After that the design method is implemented on the fan and plate laboratory system in a real environment. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  17. Integration of analog and digital instrumentation and control systems in hybrid control rooms

    International Nuclear Information System (INIS)

    2010-01-01

    he IAEA's activities in the area of nuclear power plant operating performance and life cycle management are aimed at increasing Member State capabilities in utilizing good engineering and management practices as developed and transferred by the IAEA. In particular, the IAEA supports the improvement of nuclear power plant performance, plant life management, training, power uprating, operational license renewal, and the modernization of instrumentation and control (I and C) systems of plants. The issue of the integration of analog and digital I and C systems in hybrid control rooms was suggested by the IAEA Technical Working Group on Nuclear Power Plant Control and Instrumentation (TWG-NPPCI) at its meetings in 2003 and 2005. The subject was then approved by the IAEA and included in its work programmes for 2006-2009. The purpose of this report is to help nuclear utilities in planning control room and other human system interface (HSI) changes, making appropriate use of modern technologies. These technologies would aid in managing ageing and obsolescence, and facilitate improvements in plant performance and safety. This report covers a broad spectrum of potential changes to the control room ranging from the replacement of a few obsolete components with newer digital devices to a fully computerized control room. New digital technologies offer significant opportunities to improve access to and presentation of information to the user, e.g. operators, maintenance staff and management. However, this technology should be used prudently. In some cases, modernization is undertaken to resolve ageing and obsolescence or to meet regulatory requirements for license renewal. The integration of new technologies during main control room (MCR) modernizations should be performed cautiously and all affected aspects of plant maintenance, and operation should be carefully considered, paying particular attention to the human factors elements of these aspects. This report describes a

  18. On-chip digital power supply control for system-on-chip applications

    NARCIS (Netherlands)

    Meijer, M.; Pineda de Gyvez, J.; Otten, R.H.J.M.

    2005-01-01

    The authors presented an on-chip, fully-digital, power-supply control system. The scheme consists of two independent control loops that regulate power supply variations due to semiconductor process spread, temperature, and chip's workload. Smart power-switches working as linear voltage regulators

  19. ENEA-Frascati inertial confinement fusion: Multi-channel digitizer control, acquisition and analysis system

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, A.; Strangio, C.; Elman, G.; Hugh, J. Mc; Rogers, G.; Pastina, E.; Raimondi, F.; Umbro, A.

    1991-09-01

    The ICF (Inertial Confinement Fusion) data acquisition and analysis system described in this paper incorporates digitizer channels, signal switching, an instrument controller, a graphic hardcopy unit, laser printer and software. The digitizers, signal switching and instrument controller are standard components appropriate to acquire the single fast shot signals (rise-time: from about 100 picoseconds to nanoseconds). The input signals are switched to the digitizers through the TSI-8150 test system interface by TSS40 switch controller cards and TSS46 18GHz microwave switches. Graphic hardcopy is accomplished using either a 4693PX colour hardcopy unit or a laser printer connected through a printer spooler/multiplexer. The software is based on an existing package from Ressler called RAI/DAC reviewed by Fus-Inerz and Tektronix-Italy to define the modifications needed for data acquisition and handling. The adopted software solution is based on an IBM PC compatible instrument controller running software developed by Ressler Associates.

  20. An automatic regulating control system for a graphite moderated reactor using digital techniques

    International Nuclear Information System (INIS)

    Carvalho Goncalves Junior, J. de.

    1989-01-01

    The work propose an automatic regulating control system for a graphite moderated reactor using digital techniques. The system uses a microcomputer to monitor the power and the period, to run the control algorithm, and to generate electronic signals to excite the motor, which moves vertically the control rod banks. A nuclear reactor simulator was developed to test the control system. The simulator consists of a software based on the point kinetic equations and implanted in an analogical computer. The results show that this control system has a good performance and versatility. In addition, the simulator is capable of reproducing with accuracy the behavior of a nuclear reactor. (author)

  1. Digital proportional multi-resonant current controller for improving grid-connected photovoltaic systems

    NARCIS (Netherlands)

    Almeida, de P.M.; Barbosa, P.G.; Oliveira, J.G.; Duarte, J.L.; Ribeiro, P.F.

    2015-01-01

    This paper presents the modelling and design steps of a digital proportional multi-resonant controller used in a grid-connected photovoltaic (PV) system. It is shown that the use of only one Proportional-Resonant (PR) compensator, tuned to the system fundamental frequency, may have its effectiveness

  2. An application study for the class 1E digital control and monitoring system

    International Nuclear Information System (INIS)

    Hiroyuki Fukumitsu

    1998-01-01

    This paper presents an application study for the Class 1E digital control and monitoring system to the next Japanese plants, especially about MMIS. The system architecture of hardware and software is also introduced, which will explain the strategic plan for the necessary software verification and validation according to the latest requirement from Japanese regulatory guide. (author)

  3. Experience with the New Digital RF Control System at the CESR Storage Ring

    CERN Document Server

    Liepe, Matthias; Dobbins, John; Kaplan, Roger; Strohman, Charles R; Stuhl, Benjamin K

    2005-01-01

    A new digital control system has been developed, providing great flexibility, high computational power and low latency for a wide range of control and data acquisition applications. This system is now installed in the CESR storage ring and stabilizes the vector sum field of two of the superconducting CESR 500 MHz cavities and the output power from the driving klystron. The installed control system includes in-house developed digital and RF hardware, very fast feedback and feedforward control, a state machine for automatic start-up and trip recovery, cw and pulsed mode operation, fast quench detection, and cavity frequency control. Several months of continuous operation have proven high reliability of the system. The achieved field stability surpasses requirements.

  4. A Classification Method of Technical Security Controls for Digital I and C Systems in NPPs

    International Nuclear Information System (INIS)

    Song, J. G.; Lee, J. W.; Park, G. Y.; Kwon, K. C.; Lee, D. Y.; Lee, C. K.

    2012-01-01

    The instrumentation and control (I and C) systems in nuclear power plants (NPPs) are a key facility to monitor plant state, control plant devices, and prevent accidents. Recent I and C systems have been composed of digital systems in order to enhance the effectiveness of operation and maintenance of NPPs. An assessment method for the analysis of security controls is needed to respond to potential cyber attacks against digital I and C systems. RG 5.71 'Cyber Security Programs for Nuclear Facilities' published by U.S.NRC in 2010 presents a comprehensive set of security controls for NPPs. Although this document provides the requirements of security controls, a guidance describing which security controls should be applied to specific digital assets and how to implement them is still needed for the I and C system design and development. In this paper, a classification method of the technical security controls listed in RG 5.71 is proposed to provide a guide useful for the application of the controls during the design and implementation phases of I and C systems

  5. A Classification Method of Technical Security Controls for Digital I and C Systems in NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Song, J. G.; Lee, J. W.; Park, G. Y.; Kwon, K. C.; Lee, D. Y.; Lee, C. K. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    The instrumentation and control (I and C) systems in nuclear power plants (NPPs) are a key facility to monitor plant state, control plant devices, and prevent accidents. Recent I and C systems have been composed of digital systems in order to enhance the effectiveness of operation and maintenance of NPPs. An assessment method for the analysis of security controls is needed to respond to potential cyber attacks against digital I and C systems. RG 5.71 'Cyber Security Programs for Nuclear Facilities' published by U.S.NRC in 2010 presents a comprehensive set of security controls for NPPs. Although this document provides the requirements of security controls, a guidance describing which security controls should be applied to specific digital assets and how to implement them is still needed for the I and C system design and development. In this paper, a classification method of the technical security controls listed in RG 5.71 is proposed to provide a guide useful for the application of the controls during the design and implementation phases of I and C systems

  6. The modular design method for digital control systems in Japanese BWRs

    International Nuclear Information System (INIS)

    Kondoh, Y.; Motomura, A.

    1998-01-01

    Digital technology is being applied to control systems in nuclear power plants. Especially in Japanese BWRs, control systems are being digitized both in constructing plant and in retrofit of operating plants. Digital technology has many advantages compared with analog technology. However, its high performance and flexibility may result in too complicated software structure, which will cause long design time and long testing time and increase cost. In introduction of digital technology, it is most important to restrict unnecessary flexibility of software. The function of control systems can be divided in standard part and variable part. Standard function may be common to every plant while variable function should be designed for each plant. Even in current design, standard design is preserved to be reused in next application. However, this design approach is not always effective because standard function may be changed by customer and nothing is considered for variable part even if it is large. To keep reliability and reduce cost by software reuse, Toshiba adopts modular design of control software, where standard part is designed as a set of standard functional modules and variable function is designed as a complex of standard functional modules and plant unique modules. Toshiba firstly applied modular design method to fuel handling machine control system. In this application the design work has been reduced to 30 percent by reusing of functional module which was first developed in former applications. This remarkable reduction of design work has enhanced reliability with less cost. In addition, software, has been produced and tested according to the functional module. These qualified software modules will be applied to next system and will realize highest reliability and least cost. Toshiba is now planning the application of this modular design method for every digital control system. (author)

  7. Assessing digital control system dependability using the dynamic flowgraph methodology

    International Nuclear Information System (INIS)

    Garrett, C.J.; Guarro, S.B.; Apostolakis, G.E.

    1993-01-01

    Dynamic Flowgraph Methodology (DFM) is a methodological approach to modeling and analyzing the behavior of software-driven embedded systems for the purpose of reliability/safety assessment and verification. The methodology has two fundamental goals: (a) to identify how certain postulated events may occur in a system and (b) to identify an appropriate testing strategy based on an analysis of system functional behavior. To achieve these goals, the methodology employs a modeling framework in which system models are developed in terms of causal relationships between physical variables and temporal characteristics of the execution of software modules. These models are then analyzed to determine how a certain state (desirable or undesirable) can be reached. This is done by developing timed fault trees, which take the form of logical combinations of static trees relating system parameters at different points in time. The prime implicants (multistate analog of minimal cut sets) of the fault trees can be used to identify and eliminate system faults resulting from unanticipated combinations of software logic errors, hardware failures, and adverse environmental conditions and to direct testing activity to more efficiently eliminate implementation errors by focusing on the neighborhood of potential failure modes arising from these combinations of system conditions

  8. Development of Alarm System link Drawing for Operation Support for APR1400 Digital Main Control Room

    International Nuclear Information System (INIS)

    Kim, Ki-Hwan

    2016-01-01

    Digitalized MMI(Man-Machine Interface) including Digital Main Control Room(MCR) and digital I and C system was being applied for SKN 3 and 4 Nuclear Power Plant(NPP) and subsequent APR1400 NPP type. But, operators can not easily find instrument for alarm immediately. Therefore, Alarm system is required to easily find instrument for Alarm. For this implementation, we will plan system design considering design feature without affecting network load and CPU load. We have developed Alarm system link drawing for digital MCR. Operators of the digitalized MCR navigates from their consoles to the drawings related to the plant alarms and their instruments or the operation status. Such method gives cognitive load to the operators having to travel to different locations in finding the related information. Screen Sharing System, which is the fundamental technique for Drawing Interconnection Alarm System is close to completion, and it should be functionally tested and verified by the human factor engineering. For the actual application to the operating plants, the drawings to be interconnected to the alarms and the opinions from the operators/maintenance departments for designating alarm number should be surveyed, Also, another function that allows the access to the alarm related drawings not only from the MCR but also from the other offices

  9. Development of Alarm System link Drawing for Operation Support for APR1400 Digital Main Control Room

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki-Hwan [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    Digitalized MMI(Man-Machine Interface) including Digital Main Control Room(MCR) and digital I and C system was being applied for SKN 3 and 4 Nuclear Power Plant(NPP) and subsequent APR1400 NPP type. But, operators can not easily find instrument for alarm immediately. Therefore, Alarm system is required to easily find instrument for Alarm. For this implementation, we will plan system design considering design feature without affecting network load and CPU load. We have developed Alarm system link drawing for digital MCR. Operators of the digitalized MCR navigates from their consoles to the drawings related to the plant alarms and their instruments or the operation status. Such method gives cognitive load to the operators having to travel to different locations in finding the related information. Screen Sharing System, which is the fundamental technique for Drawing Interconnection Alarm System is close to completion, and it should be functionally tested and verified by the human factor engineering. For the actual application to the operating plants, the drawings to be interconnected to the alarms and the opinions from the operators/maintenance departments for designating alarm number should be surveyed, Also, another function that allows the access to the alarm related drawings not only from the MCR but also from the other offices.

  10. Design concepts for a nuclear digital instrumentation and control system platform

    International Nuclear Information System (INIS)

    Ou, T. C.; Chen, C. K.; Chen, P. J.; Shyu, S. S.; Lee, C. L.; Hsieh, S. F.

    2010-10-01

    The objective of this paper is to present the development results of the nuclear instrumentation and control system in Taiwan. As the Taiwan nuclear power plants age, the need to consider upgrading of both their safety and non-safety-related instrumentation and control systems becomes more urgent. Meanwhile, the digital instrumentation and control system that is based on current fast evolving electronic and information technologies are difficult to maintain effectively. Therefore, Institute of Nuclear Energy Research was made a decision to promote the Taiwan Nuclear Instrumentation and Control System project to collaborate with domestic electronic industry to establish self-reliant capabilities on the design, manufacturing, and application of nuclear instrumentation and control systems with newer technology. In the case of safety-related applications like nuclear instrumentation and control, safety-oriented quality control is required. In order to establish a generic qualified digital platform, the world-wide licensing experience should be considered in the licensing process. This paper describes the qualification and certification tools by IEC 61508 for design and development of safety related equipment and explains the basis for many decisions made while performing the digital upgrade. (Author)

  11. Simulink-aided Design and Implementation of Sensorless BLDC Motor Digital Control System

    Science.gov (United States)

    Zhilenkov, A. A.; Tsvetkov, Y. N.; Chistov, V. B.; Nyrkov, A. P.; Sokolov, S. S.

    2017-07-01

    The paper describes the process of creating of brushless direct current motor’s digital control system. The target motor has no speed sensor, so back-EMF method is used for commutation control. Authors show how to model the control system in MatLab/Simulink and to test it onboard STM32F4 microcontroller.This technology allows to create the most flexible system, which will control possible with a personal computer by communication lines. It is possible to examine the signals in the circuit of the actuator without any external measuring instruments - testers, oscilloscopes, etc. - and output waveforms and measured values of signals directly on the host PC.

  12. Distributed digital real-time control system for the TCV tokamak and its applications

    NARCIS (Netherlands)

    Anand, H.; Galperti, C.; Coda, S.; Duval, B.P.; Felici, F.; Blanken, T.; Maljaars, E.; Moret, J.M.; Sauter, O.; Goodman, T.P.; Kim, D.

    2017-01-01

    A key feature of the new digital plasma control system installed on the TCV (Tokamak à Configuration Variable) tokamak is its possibility to rapidly design, test and deploy real-time algorithms. It accommodates hundreds of diagnostic inputs and actuator outputs, and offers the possibility to design

  13. Fault-tolerant design of adaptive digital control systems for power plant components

    International Nuclear Information System (INIS)

    Parlos, A.G.; Menon, S.K.

    1992-01-01

    An adaptive controller has been designed for the water level of a Westinghouse type U-tube steam generator, and its operation has been demonstrated in the entire power range via computer simulations. The proposed design exhibits improved performance, at low operating powers, a,s compared to existing controller types. The continuous-time controller design is performed systematically via the Linear Quadratic Gaussian/Loop Transfer Recovery method, followed by gain adaptation allowing controller operation in the entire power range. Digital implementation of the controller is accomplished by a digital redesign which results in matching the digital and continuous-time system and controller states. It is only at this stage of the control system design process that issues such as microprocessor induced quantization effects are taken into account. The use of computer-aided-design software greatly expedites the design cycle, allowing the designer to maximize the controller stability robustness to uncertainties via numerous iterations. This inherent controller robustness can be exploited to tolerate incipient plant faults, such as deteriorating U-tube heat transfer properties, without significant loss of controller performance

  14. Beam Tests of a New Digital Beam Control System for the CERN LEIR Accelerator

    CERN Document Server

    Angoletta, Maria Elena; Blas, Alfred; De Long, Joseph; Findlay, Alan; Matuszkiewicz, Pawel; Pedersen, Flemming; Salom-Sarasqueta, Angela

    2005-01-01

    The Low Energy Ion Ring (LEIR) is a major component in the Large Hadron Collider ion injector chain. We have been developing an all-digital beam control and cavity servo system for the RF acceleration in LEIR. The system is housed by VME motherboards that may hold various daughter boards. Fast tasks are executed in Field Programmable Gate Arrays (FPGAs), slower tasks and communication with the software layer above are achieved in Digital Signal Processors (DSPs). We describe a simplified system prototype, which we tested with low intensity beams on the CERN PS Booster (PSB). The aim was to verify the combined DSP+FPGA architecture and the feedback loop dynamics. An additional goal was to deploy and validate novel software concepts, such as reference-functions and timings generation, and user-selectable digital data acquisition.

  15. Digital control systems training on a distance learning platform

    Directory of Open Access Journals (Sweden)

    Jan PIECHA

    2009-01-01

    Full Text Available The paper deals with new training technologies development based on approach to distance learning website, implemented in the laboratory of a Traffic Engineering study branch at Faculty of Transport. The discussed computing interface allows students complete knowledge of traffic controllers’ architecture and machine language programming fundamentals. These training facilities are available at home; at their remote terminal. The training resources consist of electronic / computer based training; guidebooks and software units. The laboratory provides the students with an interface entering into simulation packages and programming interfaces, supporting the web training facilities. The courseware complexity selection is one of the most difficult factors in intelligent training unit’s development. The dynamically configured application provides the user with his individually set structure of the training resources. The trainee controls the application structure and complexity, from the time he started. For simplifying the training process and studying activities, several unifications were provided. The introduced ideas need various standardisations, simplifying the e-learning units’ development and application control processes [8], [9]. Further training facilities development concerns virtual laboratory environment organisation in laboratories of Transport Faculty.

  16. Digitization and simulation realization of full range control system for steam generator water level

    International Nuclear Information System (INIS)

    Qian Hong; Ye Jianhua; Qian Fei; Li Chao

    2010-01-01

    In this paper, a full range digital control system for the steam generator water level is designed by a control scheme of single element control and three-element cascade feed-forward control, and the method to use the software module configuration is proposed to realize the water level control strategy. This control strategy is then applied in the operation of the nuclear power simulation machine. The simulation result curves indicate that the steam generator water level maintains constant at the stable operation condition, and when the load changes, the water level changes but finally maintains the constant. (authors)

  17. A monitor for the laboratory evaluation of control integrity in digital control systems operating in harsh electromagnetic environments

    Science.gov (United States)

    Belcastro, Celeste M.; Fischl, Robert; Kam, Moshe

    1992-01-01

    This paper presents a strategy for dynamically monitoring digital controllers in the laboratory for susceptibility to electromagnetic disturbances that compromise control integrity. The integrity of digital control systems operating in harsh electromagnetic environments can be compromised by upsets caused by induced transient electrical signals. Digital system upset is a functional error mode that involves no component damage, can occur simultaneously in all channels of a redundant control computer, and is software dependent. The motivation for this work is the need to develop tools and techniques that can be used in the laboratory to validate and/or certify critical aircraft controllers operating in electromagnetically adverse environments that result from lightning, high-intensity radiated fields (HIRF), and nuclear electromagnetic pulses (NEMP). The detection strategy presented in this paper provides dynamic monitoring of a given control computer for degraded functional integrity resulting from redundancy management errors, control calculation errors, and control correctness/effectiveness errors. In particular, this paper discusses the use of Kalman filtering, data fusion, and statistical decision theory in monitoring a given digital controller for control calculation errors.

  18. Digital communication system

    International Nuclear Information System (INIS)

    Union, D.C.

    1980-01-01

    A digital communication system for communicating among two central consoles and a plurality of local controllers, e.g. in a radiation and monitoring system, provides communication between each of the consoles and all of the local controllers via dual paths. Each path is independent of the other and each extends from one of the consoles to all of the local controllers from opposite directions, thereby forming a unique non-continuous loop. (author)

  19. New digital control and power protection system of VR 1 training reactor

    International Nuclear Information System (INIS)

    Kropik, M.; Matejka, K.; Juoeickova, M.

    2005-01-01

    The contribution describes the new VR-1 training reactor control and power protection system at the Czech Technical University in Prague. The control system provides safety and control functions, calculates average values of the important variables and sends data and system status to the human-machine interface. The upgraded control system is based on a high quality industrial PC. The operating system of the PC is the Microsoft Windows XP with the real time support RTX of the VentureCom Company. The software was developed according to requirements in MS Visual C. The independent power protection system is a component of the reactor safety (protection) system with high quality and reliability requirements. The digital system is redundant; each channel evaluates the reactor power and the velocity of power changes and provides safety functions. The digital part of the channel is multiprocessor-based. The software was developed with respect to nuclear standards. The software design was coded in the C language regarding the NRC restrictions. Configuration management, verification and validation accompanied the software development. Both systems were thoroughly tested. Firstly, the non active tests were carried out. During these tests, the active core of the reactor was subcritical; the input signals were generated from HPIB and VXI controlled instruments to simulate different operational and safety events. The software for instruments control and tests evaluation utilized Agilent VEE development system. After the successful non active checking, the active tests followed. (author)

  20. Networked control of discrete-time linear systems over lossy digital communication channels

    Science.gov (United States)

    Jin, Fang; Zhao, Guang-Rong; Liu, Qing-Quan

    2013-12-01

    This article addresses networked control problems for linear time-invariant systems. The insertion of the digital communication network inevitably leads to packet dropout, time delay and quantisation error. Due to data rate limitations, quantisation error is not neglected. In particular, the case where the sensors and controllers are geographically separated and connected via noisy, bandwidth-limited digital communication channels is considered. A fundamental limitation on the data rate of the channel for mean-square stabilisation of the closed-loop system is established. Sufficient conditions for mean-square stabilisation are derived. It is shown that there exists a quantisation, coding and control scheme to stabilise the unstable system over packet dropout communication channels if the data rate is larger than the lower bound proposed in our result. An illustrative example is given to demonstrate the effectiveness of the proposed conditions.

  1. Regulatory perspective on digital instrumentation and control systems for future advanced nuclear power plants

    International Nuclear Information System (INIS)

    Chiramal, M.

    1993-01-01

    This paper deals with the question of using digital technology in instrumentation and control systems for modern nuclear power reactors. The general opinion in the industry and among NRC staff is that such technology provides the opportunity for enhanced safety and reliable reactor operations. The major concern is the safe application of this technology so as to avoid common mode or common cause failures in systems. There are great differences between digital and analog system components. SECY-91-292 identifies some general regulatory concerns with regard to digital systems. There is clearly a lack of adequate regulatory direction on the application of digital equipment at this time, but the issue is being addressed by the industry, outside experts, and NRC staff. NRC staff presents a position on the issue of defense-in-depth and diversity with regard to insuring plant safety. Independent manual controls and readouts must be available to allow safe shutdown and monitoring of the plant in the event of safety system failures

  2. Development, structure and qualification of a new digital instrumentation and control system

    International Nuclear Information System (INIS)

    Hofmann, H.; Sauer, H.J.

    1991-01-01

    Introduction of digital instrumentation and control in nuclear power plants is characterized by the need to meet numerous requirements concerning reliability, ergonomic design of the main control room and comprehensive qualification. The system described here is distinguished by a hierarchical and modular structure, being redundant throughout. Ergonomic considerations dominate the layout of the screen-based main control room. Powerful computer-aided engineering tools are employed for planning of the entire system and for generation of the user software. Qualification is performed in step with the development of the system, based on the applicable national and international rules and regulations and in close cooperation with an independent expert. (orig.) [de

  3. Vulnerability Identification and Design-Improvement-Feedback using Failure Analysis of Digital Control System Designs

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eunchan; Bae, Yeonkyoung [Korea Hydro and Nuclear Power Co., Ltd., Daejeon (Korea, Republic of)

    2013-05-15

    Fault tree analyses let analysts establish the failure sequences of components as a logical model and confirm the result at the plant level. These two analyses provide insights regarding what improvements are needed to increase availability because it expresses the quantified design attribute of the system as minimal cut sets and availability value interfaced with component reliability data in the fault trees. This combined failure analysis method helps system users understand system characteristics including its weakness and strength in relation to faults in the design stage before system operation. This study explained why a digital system could have weaknesses in methods to transfer control signals or data and how those vulnerabilities could cause unexpected outputs. In particular, the result of the analysis confirmed that complex optical communication was not recommended for digital data transmission in the critical systems of nuclear power plants. Regarding loop controllers in Design A, a logic configuration should be changed to prevent spurious actuation due to a single failure, using hardware or software improvements such as cross checking between redundant modules, or diagnosis of the output signal integrity. Unavailability calculations support these insights from the failure analyses of the systems. In the near future, KHNP will perform failure mode and effect analyses in the design stage before purchasing non-safety-related digital system packages. In addition, the design requirements of the system will be confirmed based on evaluation of overall system availability or unavailability.

  4. Design and development experience with a digital fly-by-wire control system in an F-8C airplane

    Science.gov (United States)

    Deets, D. A.

    1976-01-01

    To assess the feasibility of a digital fly by wire system, the mechanical flight control system of an F-8C airplane was replaced with a digital primary system and an analog backup system. The Apollo computer was used as the heart of the primary system. This paper discusses the experience gained during the design and development of the system and relates it to active control systems that are anticipated for future civil transport applications.

  5. Design and flight experience with a digital fly-by-wire control system in an F-8 airplane

    Science.gov (United States)

    Deets, D. A.; Szalai, K. J.

    1974-01-01

    A digital fly-by-wire flight control system was designed, built, and for the first time flown in an airplane. The system, which uses components from the Apollo guidance system, is installed in an F-8 airplane as the primary control system. A lunar module guidance computer is the central element in the three-axis, single-channel, multimode, digital control system. A triplex electrical analog system which provides unaugmented control of the airplane is the only backup to the digital system. Flight results showed highly successful system operation, although the trim update rate was inadequate for precise trim changes, causing minor concern. The use of a digital system to implement conventional control laws proved to be practical for flight. Logic functions coded as an integral part of the control laws were found to be advantageous. Although software verification required extensive effort, confidence in the software was achieved.

  6. A digitized wide range channel for new instrumentation and control system of PUSPATI TRIGA Reactor (RTP)

    International Nuclear Information System (INIS)

    Zareen Khan Abdul Jalil Khan; Izhar Abu Hussin; Mohd Idris Taib; Nurfarhana Ayuni Joha; Roslan Md Dan

    2010-01-01

    Wide Range Channel is one of very important part of Reactor Instrumentation and Control system. Current system is using all analog system. The main functions of the new system are to provide Wide-log power and Multi-range linear power. The other functions are to provide Percent power and Power rate of change. The linear power level range is up to 125 % and the log power system to cover from below source level to 150 %. The main function of digital signal processor is for pulse shaping, pulse counting and root mean square signal processing. The system employs automatic on-line self diagnostics and calibration verification. (author)

  7. Modernization of control system using the digital control system; Modernizacion de sistemas de control usando la simulacion como herramiento de ingenieria

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, J. A.; Fernandez, L.; Jimenez, A.

    2002-07-01

    Nowadays, all plant automation tendencies are based on the use of Digital Control System. In big industrial plants the control systems employed are Distributed Control Systems (DCS). The addition of these systems in nuclear power plants,implies an important adaptation process, because most of them were installed using analog control systems. This paper presents the objectives and the first results obtained, in a modernization project, focused in obtaining an engineering platform for making test and analysis of changes prior to their implementation in a nuclear plant. Modernization, Upgrade, DCS, Automation, Simulation, Training. (Author)

  8. The Effect of Degraded Digital Instrumentation and Control systems on Human-system Interfaces and Operator Performance

    International Nuclear Information System (INIS)

    O'Hara, J.M.; Gunther, B.; Martinez-Guridi, G.; Xing, J.; Barnes, V.

    2010-01-01

    Integrated digital instrumentation and control (I and C) systems in new and advanced nuclear power plants (NPPs) will support operators in monitoring and controlling the plants. Even though digital systems typically are expected to be reliable, their potential for degradation or failure significantly could affect the operators performance and, consequently, jeopardize plant safety. This U.S. Nuclear Regulatory Commission (NRC) research investigated the effects of degraded I and C systems on human performance and on plant operations. The objective was to develop technical basis and guidance for human factors engineering (HFE) reviews addressing the operator's ability to detect and manage degraded digital I and C conditions. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we evaluated the potential effects of selected failure modes of the digital feedwater control system of a currently operating pressurized water reactor (PWR) on human-system interfaces (HSIs) and the operators performance. Our findings indicated that I and C degradations are prevalent in plants employing digital systems, and the overall effects on the plant's behavior can be significant, such as causing a reactor trip or equipment to operate unexpectedly. I and C degradations may affect the HSIs used by operators to monitor and control the plant. For example, deterioration of the sensors can complicate the operators interpretation of displays, and sometimes may mislead them by making it appear that a process disturbance has occurred. We used the findings as the technical basis upon which to develop HFE review guidance.

  9. Method for fault diagnosis of digital control systems in nuclear power plant

    International Nuclear Information System (INIS)

    Suzuki, Satoshi; Nagaoka, Yukio; Ohga, Yukiharu; Ito, Tetsuo

    1990-01-01

    This paper presents a method for localizing faulty components of control systems by replaceable parts such as print boards and cables, in a large scale plant like a nuclear power plant. Most of today's control systems form a distributed configuration including many digital controllers interconnected by data communication networks. Usually, to localize the faulty components in nuclear plant control systems, suspected faulty components are narrowed down by executing manual tests to examine whether the objects are normal or abnormal based on design documents and personnel know-how, besides the uses of self-diagnosis functions built into the control systems. In the present method, procedures of various tests including the know-how and checking of self-diagnosis functions are provided as knowledge of tests. The tests to be executed is determined by considering failure probabilities of objects, and easiness and effectiveness of testing. Then, the suspects are narrowed down sequentially based on the test result. In checking feasibility of this diagnosis method for a simulated control system, intended faults are satisfactorily localized. This method is confirmed to be practicable for diagnosis of large scale digital control systems. (author)

  10. Stability and performance analysis of a jump linear control system subject to digital upsets

    Science.gov (United States)

    Wang, Rui; Sun, Hui; Ma, Zhen-Yang

    2015-04-01

    This paper focuses on the methodology analysis for the stability and the corresponding tracking performance of a closed-loop digital jump linear control system with a stochastic switching signal. The method is applied to a flight control system. A distributed recoverable platform is implemented on the flight control system and subject to independent digital upsets. The upset processes are used to stimulate electromagnetic environments. Specifically, the paper presents the scenarios that the upset process is directly injected into the distributed flight control system, which is modeled by independent Markov upset processes and independent and identically distributed (IID) processes. A theoretical performance analysis and simulation modelling are both presented in detail for a more complete independent digital upset injection. The specific examples are proposed to verify the methodology of tracking performance analysis. The general analyses for different configurations are also proposed. Comparisons among different configurations are conducted to demonstrate the availability and the characteristics of the design. Project supported by the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 61403395), the Natural Science Foundation of Tianjin, China (Grant No. 13JCYBJC39000), the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry, China, the Tianjin Key Laboratory of Civil Aircraft Airworthiness and Maintenance in Civil Aviation of China (Grant No. 104003020106), and the Fund for Scholars of Civil Aviation University of China (Grant No. 2012QD21x).

  11. A dynamic failure evaluation of a simplified digital control system of a nuclear power plant pressurizer

    International Nuclear Information System (INIS)

    Pinto, J.M.O.; Melo, P.F. Frutuoso e; Saldanha, P.L.C.

    2010-01-01

    Given the increasing use of digital systems in nuclear power plants, a specific approach to reliability and risk analysis has been required. The digital system reflects many interactions between hardware, software, process variables, and human actions. At the same time, the software, does not have a reliability approach as well-defined as the one existing for the other physical components of the system. Then, its reliability analysis is still under development due to difficulties arising from the complexity, flexibility and interactions present in such systems.The traditional approach of using fault trees is static and does not approach the dynamic interactions in such systems, such as delays in capture and processing information, memory, logic loops, system states, etc. It is necessary to find a reliability methodology that takes into account these issues without violating the existing requirements concerning safety analysis, such as: ability to distinguish between common-cause failures, availability of relevant information to users, like minimal cut sets, and failure probabilities as long as the possibility of incorporating the results into existing probabilistic safety assessments (PSA).One approach is to trace all the possible errors of the digital system through dynamic methodologies. The DFM (Dynamic Flow-graph Methodology) is one of the methodologies that better meets the requirements for modeling dynamic systems. It discretizes the most relevant variables of the analyzed system in states that reflect their behavior, sets the logic that connects them through decision tables and finally performs a system analysis, aiming, for example, the root causes (prime implicants) of a given top event of failure. Three aspects have been addressed, the modeling of the system itself, the incorporation of results to probabilistic safety analyses and identification of software failures.To illustrate the DFM, a simplified digital control system of a typical PWR pressurizer

  12. The digital reactor protection system for the instrumentation and control of reactor TRIGA PUSPATI (RTP)

    International Nuclear Information System (INIS)

    Nurfarhana Ayuni Joha; Izhar Abu Hussin; Mohd Idris Taib; Zareen Khan Abdul Jalil Khan

    2010-01-01

    Reactor Protection System (RPS) is important for Reactor Instrumentation and Control System. The RPS comprises all redundant electrical devices and circuitry involved in the generation of those initiating signals associated to the trip protective function. The instrumentation system for the RPS provides automatic protection signals against unsafe and improper reactor operation. The physical separation is provided for all of the redundant instrumentation systems to preserve redundancy. The safety protection systems using circuits composed of analog instruments and relays with relay contacts is difficult to realize from various reasons. Therefore, an application of digital technology can be said a logical conclusion also in the light of its functional superiority. (author)

  13. Digital low level RF control system for the DESY TTF VUV-FEL Linac

    International Nuclear Information System (INIS)

    Ayvazyan, V.; Choroba, S.; Matyushin, A.; Moeller, G.; Petrosyan, G.; Rehlich, K.; Simrock, S.N.; Vetrov, P.

    2005-01-01

    In the RF system for the Vacuum Ultraviolet Free Electron Laser (VUV-FEL) Linac each klystron supplies RF power to up to 32 cavities. The superconducting cavities are operated in pulsed mode and high accelerating gradients close to the performance limit. The RF control of the cavity fields to the level of 10 -4 for amplitude and 0.1 degree for phase however presents a significant technical challenge due to the narrow bandwidth of the cavities which results in high sensitivity to perturbations of the resonance frequency by mechanical vibrations (microphonics) and Lorenz force detuning. The VUV-FEL Linac RF control system employs a completely digital feedback system to provide flexibility in the control algorithms, precise calibration of the accelerating field vector-sum, and extensive diagnostics and exception handling capabilities. The RF control algorithm is implemented in DSP (Digital Signal Processor) firmware and DOOCS (Distributed Object Oriented Control System) servers. The RF control system design objectives are discussed. Hardware and software design of the DSP based RF control are presented. (orig.)

  14. Digital low level RF control system for the DESY TTF VUV-FEL Linac

    Energy Technology Data Exchange (ETDEWEB)

    Ayvazyan, V.; Choroba, S.; Matyushin, A.; Moeller, G.; Petrosyan, G.; Rehlich, K.; Simrock, S.N.; Vetrov, P.

    2005-07-01

    In the RF system for the Vacuum Ultraviolet Free Electron Laser (VUV-FEL) Linac each klystron supplies RF power to up to 32 cavities. The superconducting cavities are operated in pulsed mode and high accelerating gradients close to the performance limit. The RF control of the cavity fields to the level of 10{sup -4} for amplitude and 0.1 degree for phase however presents a significant technical challenge due to the narrow bandwidth of the cavities which results in high sensitivity to perturbations of the resonance frequency by mechanical vibrations (microphonics) and Lorenz force detuning. The VUV-FEL Linac RF control system employs a completely digital feedback system to provide flexibility in the control algorithms, precise calibration of the accelerating field vector-sum, and extensive diagnostics and exception handling capabilities. The RF control algorithm is implemented in DSP (Digital Signal Processor) firmware and DOOCS (Distributed Object Oriented Control System) servers. The RF control system design objectives are discussed. Hardware and software design of the DSP based RF control are presented. (orig.)

  15. Digital radiation monitor system

    International Nuclear Information System (INIS)

    Quan Jinhu; Zhai Yongchun; Guan Junfeng; Ren Dangpei; Ma Zhiyuan

    2003-01-01

    The article introduced digital radiation monitor system. The contents include: how to use advanced computer net technology to establish equipment net for nuclear facility, how to control and manage measuring instruments on field equipment net by local area net, how to manage and issue radiation monitoring data by internet

  16. Applying Human Factors Evaluation and Design Guidance to a Nuclear Power Plant Digital Control System

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Ulrich; Ronald Boring; William Phoenix; Emily Dehority; Tim Whiting; Jonathan Morrell; Rhett Backstrom

    2012-08-01

    The United States (U.S.) nuclear industry, like similar process control industries, has moved toward upgrading its control rooms. The upgraded control rooms typically feature digital control system (DCS) displays embedded in the panels. These displays gather information from the system and represent that information on a single display surface. In this manner, the DCS combines many previously separate analog indicators and controls into a single digital display, whereby the operators can toggle between multiple windows to monitor and control different aspects of the plant. The design of the DCS depends on the function of the system it monitors, but revolves around presenting the information most germane to an operator at any point in time. DCSs require a carefully designed human system interface. This report centers on redesigning existing DCS displays for an example chemical volume control system (CVCS) at a U.S. nuclear power plant. The crucial nature of the CVCS, which controls coolant levels and boration in the primary system, requires a thorough human factors evaluation of its supporting DCS. The initial digital controls being developed for the DCSs tend to directly mimic the former analog controls. There are, however, unique operator interactions with a digital vs. analog interface, and the differences have not always been carefully factored in the translation of an analog interface to a replacement DCS. To ensure safety, efficiency, and usability of the emerging DCSs, a human factors usability evaluation was conducted on a CVCS DCS currently being used and refined at an existing U.S. nuclear power plant. Subject matter experts from process control engineering, software development, and human factors evaluated the DCS displays to document potential usability issues and propose design recommendations. The evaluation yielded 167 potential usability issues with the DCS. These issues should not be considered operator performance problems but rather opportunities

  17. Regulatory issues of digital instrumentation and control system in Lungmen project

    International Nuclear Information System (INIS)

    Chuang, C.F.; Chou, H.P.

    2004-01-01

    The Lungmen Nuclear Power Station (LNPS) is currently under construction in Taiwan, which consists of 2 advanced boiling water reactor (ABWR) units. The instrumentation and control (IC) systems of the LNPS are based on the state-of-the-art modernized fully integrated digital design. These IC systems possess many advantages and distinguished features comparing to traditional analog IC systems, they enjoy set-point stability, self-diagnostic and automatic testing ability, fault tolerance and avoidance, low power requirements, data handling and storage capability, as well as enhanced human-machine interfaces. This paper presents regulatory overviews, regulatory requirements, current major regulatory issues, as well as the areas of regulatory concerns and the lessons learned on the digital IC systems in the Lungmen Project

  18. Flight Test Results for the F-16XL With a Digital Flight Control System

    Science.gov (United States)

    Stachowiak, Susan J.; Bosworth, John T.

    2004-01-01

    In the early 1980s, two F-16 airplanes were modified to extend the fuselage length and incorporate a large area delta wing planform. These two airplanes, designated the F-16XL, were designed by the General Dynamics Corporation (now Lockheed Martin Tactical Aircraft Systems) (Fort Worth, Texas) and were prototypes for a derivative fighter evaluation program conducted by the United States Air Force. Although the concept was never put into production, the F-16XL prototypes provided a unique planform for testing concepts in support of future high-speed supersonic transport aircraft. To extend the capabilities of this testbed vehicle the F-16XL ship 1 aircraft was upgraded with a digital flight control system. The added flexibility of a digital flight control system increases the versatility of this airplane as a testbed for aerodynamic research and investigation of advanced technologies. This report presents the handling qualities flight test results covering the envelope expansion of the F-16XL with the digital flight control system.

  19. Incorporation of Markov reliability models for digital instrumentation and control systems into existing PRAs

    International Nuclear Information System (INIS)

    Bucci, P.; Mangan, L. A.; Kirschenbaum, J.; Mandelli, D.; Aldemir, T.; Arndt, S. A.

    2006-01-01

    Markov models have the ability to capture the statistical dependence between failure events that can arise in the presence of complex dynamic interactions between components of digital instrumentation and control systems. One obstacle to the use of such models in an existing probabilistic risk assessment (PRA) is that most of the currently available PRA software is based on the static event-tree/fault-tree methodology which often cannot represent such interactions. We present an approach to the integration of Markov reliability models into existing PRAs by describing the Markov model of a digital steam generator feedwater level control system, how dynamic event trees (DETs) can be generated from the model, and how the DETs can be incorporated into an existing PRA with the SAPHIRE software. (authors)

  20. Key Regulatory Issues for Digital Instrumentation and Control Systems at Nuclear Power Plants

    International Nuclear Information System (INIS)

    Korsah, Kofi; Wood, Richard Thomas

    2008-01-01

    To help reduce the uncertainty associated with application of digital instrumentation and controls (I and C) technology in nuclear power plants, the Nuclear Regulatory Commission (NRC) has issued six Interim Staff Guidance (ISG) documents that address the current regulatory positions on what are considered the significant digital I and C issues. These six documents address the following topics: Cyber Security, Diversity and Defense-in-Depth, Risk Informed Digital I and C Regulation, Communication issues, Human Factors and the Digital I and C Licensing Process (currently issued as Draft). After allowing for further refinement based on additional technical insight gathered by NRC staff through near-term research and detailed review of relevant experience, it is expected that updated positions ultimately will be incorporated into regulatory guides and staff review procedures. This paper presents an overview of the guidance provided by the NRC-issued ISGs on key technology considerations (i.e., the first five documents above) for safety-related digital I and C systems.

  1. Design and modernization of the control room with of the new digital I and C systems

    International Nuclear Information System (INIS)

    Fernandez, L. A.; Ortega, F.; Rejas, L.

    2011-01-01

    The use of the new digital I and c systems in the design of the new nuclear power plants, as well as the modernization of the existing ones, implies relevant changes in the control room design. New I and C systems provide new features that affect the control room operating concept, therefore a detailed analysis is required to take into consideration all the operating and human factor aspects. based on Tecnatom's experience, this article presents the methodological approach used as well as the most relevant aspects of this kind of project. (Author)

  2. TESLA cavity modeling and digital implementation in FPGA technology for control system development

    International Nuclear Information System (INIS)

    Czarski, T.; Pozniak, K.T.; Romaniuk, R.S.; Simrock, S.

    2006-01-01

    The electromechanical model of the TESLA cavity has been implemented in FPGA technology for real-time testing of the control system. The model includes Lorentz force detuning and beam loading effects. Step operation and vector stimulus operation modes are applied for the evaluation of a FPGA cavity simulator operated by a digital controller. The performance of the cavity hardware model is verified by comparing with a software model of the cavity implemented in the MATLAB system. The numerical aspects are considered for an optimal DSP calculation. Some experimental results are presented for different cavity operational conditions. (orig.)

  3. Digital Control of a power conditioner for fuel cell/super-capacitor hybrid system

    DEFF Research Database (Denmark)

    Caballero, Juan C Trujillo; Gomis-Bellmunt, Oriol; Montesinos-Miracle, Daniel

    2014-01-01

    This article proposes a digital control scheme to operate a proton exchange membrane fuel cell module of 1.2 kW and a super-capacitor through a DC/DC hybrid converter. A fuel cell has been proposed as a primary source of energy, and a super-capacitor has been proposed as an auxiliary source...... of energy. Experimental validation of the system implemented in the laboratory is provided. Several tests have been performed to verify that the system achieves excellent output voltage (V0) regulation and super-capacitor voltage (V SC) control under disturbances from fuel cell power (PFC) and output power...

  4. Implementing digital instrumentation and control systems in the modernization of nuclear power plants

    International Nuclear Information System (INIS)

    2009-01-01

    The IAEA encourages greater use of good engineering and management practices by Member States. In particular, it supports activities such as nuclear power plant (NPP) performance improvement, plant life management, training, power uprating, operational license renewal and the modernization of instrumentation and control (I and C) systems of NPPs in Member States. The subject of implementing digital I and C systems in nuclear power plants was suggested by the Technical Working Group on Nuclear Power Plant Control and Instrumentation (TWG-NPPCI) in 2003. It was then approved by the IAEA and included in the programmes for 2006-2008. As the current worldwide fleet of nuclear power plants continues ageing, the need for improvements to maintain or enhance plant safety and reliability is increasing. Upgrading NPP I and C systems is one of the possible approaches to achieving this improvement, and in many cases upgrades are a necessary activity for obsolescence management. I and C upgrades at operating plants require the use of digital I and C equipment. While modernizing I and C systems is a significant undertaking, it is an effective means to enhance plant safety and system functionality, manage obsolescence, and mitigate the increasing failure liability of ageing analog systems. Many of the planning and implementation tasks of a digital I and C upgrade project described here are also relevant to new plant design and construction since all equipment in new plants will be digital. This publication explains a process for planning and conducting an I and C modernization project. Numerous issues and areas requiring special consideration are identified, and recommendations on how to integrate the licensing authority into the process are made. To complement this report, a second publication is planned which will illustrate many of the aspects described here through experience based descriptions of I and C projects and lessons learned from those activities. It is upon these

  5. Analysis Method of Common Cause Failure on Non-safety Digital Control System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yun Goo; Oh, Eun Gse [KHNP, Daejeon (Korea, Republic of)

    2014-08-15

    The effects of common cause failure on safety digital instrumentation and control system had been considered in defense in depth analysis with safety analysis method. However, the effects of common cause failure on non-safety digital instrumentation and control system also should be evaluated. The common cause failure can be included in credible failure on the non-safety system. In the I and C architecture of nuclear power plant, many design feature has been applied for the functional integrity of control system. One of that is segmentation. Segmentation defenses the propagation of faults in the I and C architecture. Some of effects from common cause failure also can be limited by segmentation. Therefore, in this paper there are two type of failure mode, one is failures in one control group which is segmented, and the other is failures in multiple control group because that the segmentation cannot defense all effects from common cause failure. For each type, the worst failure scenario is needed to be determined, so the analysis method has been proposed in this paper. The evaluation can be qualitative when there is sufficient justification that the effects are bounded in previous safety analysis. When it is not bounded in previous safety analysis, additional analysis should be done with conservative assumptions method of previous safety analysis or best estimation method with realistic assumptions.

  6. 162.5 MHz digital low-level radio frequency control monitoring system design and implementation

    International Nuclear Information System (INIS)

    Zhang Ruifeng; Wang Xianwu; Xu Zhe; Yi Xiaoping

    2014-01-01

    162.5 MHz high-frequency low-level control system self-developed by Institute of Modern Physics for ADS project took digital technology. All parameters' reading and writing, including loop parameter setting, open and close-loop operation, and condition monitoring, were achieved through the monitoring system. The system used lightweight client-server working mode that client running in the PC sent command data, server running on high-frequency digital low level system responded instructions to complete parameter monitoring and control. The system consisted of three parts. Firstly, server hardware system was constructed based on Atera Stratix Ⅲ family of field-programmable gate array (FPGA) development board. Secondly, the server software system was designed based on Micro C/OS Ⅱ real-time operating systems and lightweight TCP/IP protocol stack, and finally a client PC program was designed based on MFC. After a long test, it was indicated that the monitoring system works properly and stably. TCP sends and receives throughput reached 11.931038 Mbps and 8.117624 Mbps. (authors)

  7. Digitized operator evaluation system for main control room of nuclear power plant

    International Nuclear Information System (INIS)

    Chen Yu; Yan Shengyuan; Chen Wenlong

    2014-01-01

    In order to evaluate the human-machine system matching relation of main control room in nuclear power plant accurately and efficiently, the expression and parameters of operator human body model were analyzed, and the evaluation required function of digital operator was determined. Based on the secondary development technology, the digital operator evaluation body model was developed. It could choose generation, gender, operation posture, single/eyes horizon, and left/right hand up to the domain according to the needs of specific evaluation, it was used to evaluate whether display information can be visible and equipment can be touch, and it also has key evaluation functions such as workspace and character visibility at the same time. The examples show that this method can complete the evaluation work of human-machine matching relation for main control room of nuclear power plant accurately, efficiently and quickly, and achieve the most optimal human-machine coordination relationship. (authors)

  8. Implementation of an advanced digital feedwater control system at the Prairie Island nuclear generating station

    International Nuclear Information System (INIS)

    Paris, R.E.; Gaydos, K.A.; Hill, J.O.; Whitson, S.G.; Wirkkala, R.

    1990-05-01

    EPRI Project RP2126-4 was a cooperative effort between TVA, EPRI, and Westinghouse which resulted in the demonstration of a prototype of a full range, fully automatic feedwater control system, using fault tolerant digital technology, at the TVA Sequoyah simulator site. That prototype system also included advanced signal validation algorithms and an advanced man-machine interface that used CRT-based soft-control technology. The Westinghouse Advanced Digital Feedwater Control System (ADFCS) upgrade, which contains elements that were part of that prototype system, has since been installed at Northern States Power's Prairie Island Unit 2. This upgrade was very successful due to the use of an advanced control system design and the execution of a well coordinated joint effort between the utility and the supplier. The project experience is documented in this report to help utilities evaluate the technical implications of such a project. The design basis of the Prairie Island ADFCS signal validation for input signal failure fault tolerance is outlined first. Features of the industry-proven system control algorithms are then described. Pre-shipment hardware-in-loop and factory acceptance testing of the Prairie Island system are summarized. Post-shipment site testing, including preoperational and plant startup testing, is also summarized. Plant data from the initial system startup is included. The installation of the Prairie Island ADFCS is described, including both the feedwater control instrumentation and the control board interface. Modification of the plant simulator and operator and I ampersand C personnel training are also discussed. 6 refs., 14 figs., 3 tabs

  9. Analysis approach for common cause failure on non-safety digital control system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yun Goo; Oh, Eungse [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of)

    2014-05-15

    The effects of common cause failure (CCF) on safety digital instrumentation and control (I and C) system had been considered in defense in depth and diversity coping analysis with safety analysis method. For the non-safety system, single failure had been considered for safety analysis. IEEE Std. 603-1991, Clause 5.6.3.1(2), 'Isolation' states that no credible failure on the non-safety side of an isolation device shall prevent any portion of a safety system from meeting its minimum performance requirements during and following any design basis event requiring that safety function. The software CCF is one of the credible failure on the non-safety side. In advanced digital I and C system, same hardware component is used for different control system and the defect in manufacture or common external event can generate CCF. Moreover, the non-safety I and C system uses complex software for its various function and software quality assurance for the development process is less severe than safety software for the cost effective design. Therefore the potential defects in software cannot be ignored and the effect of software CCF on non-safety I and C system is needed to be evaluated. This paper proposes the general process and considerations for the analysis of CCF on non-safety I and C system.

  10. Quality control: comparison of images quality with screen film system and digital mammography CR

    International Nuclear Information System (INIS)

    Alvarenga, Frederico L.; Nogueira, Maria do Socorro

    2008-01-01

    The mammography screen film system should be used as part of processing chemicals, revelation process, equipment and this system has have a progressive replacing by the digital technology Full Field Digital Mammography FFDM, Computed Radiography (CR) Mammography and hardcopy. This new acquisition process of medical images has improved radiology section; however it is necessary efficient means for evaluating of the quality parameters. It should be considered taking into account the adaptation of the existent equipment and that procedures adopted for the exam, as well the adaptation of the new mammography films, the radiologist view box constitutes a part of the quality control program. This program aims at obtaining radiography with good quality that allows obtaining more information for the diagnosis and decreases the patient dose. For evaluation the quality image, this article is focused on presenting the differences regarding the acquired images through simulator mammography radiographic PMMA (Poly methyl methacrylate) in CR Mammography system and screen film system. The tests were accomplished at the same equipment of Mammography with the Automatic Exposure Control using a tension of 28 kV for both systems. The quality tests evaluated the spatial resolution, the own structures of the phantom, artifacts, optical density and contrast with conventional and laser films by mammography system. The installation for the accomplishment of the test has a quality control program. The evaluation was based on the pattern developed by the competent organ of the State of Minas Gerais. In this study, it was verified that the suitable Phantom Mama used by the Brazilian School of Radiology for conventional mammography did not obtain satisfactory result for Spatial Resolution in the digital mammography system CR. The final aim of this work is to obtain parameters to characterize the reference phantom quality image in an objective way. These parameters will be used to compare

  11. Analyzing the decision making process of certifying digital control systems of nuclear power plants

    International Nuclear Information System (INIS)

    Yih, Swu; Fan, Chin-Feng

    2012-01-01

    Highlights: ► We have performed basic research in analyzing certification process and developed a regulatory decision making model for nuclear digital control system certification. The model views certification as an evidence–confidence conversion process. ► We have applied this model to analyze previous nuclear digital I and C certification experiences and obtained valuable insights. ► Furthermore, a prototype of a computer-aided licensing support system based on the model has been developed to enhance regulatory review efficiency. - Abstract: Safety-critical computing systems need regulators’ approval before operation. Such a permit issue process is called “certification”. Digital instrumentation and Control (I and C) certification in the nuclear domain has always been problematic and lengthy. Thus, the certification efficiency has always been a crucial concern to the applicant whose business depends on the regulatory decision. However, to our knowledge, there is little basic research on this topic. This study presents a Regulatory Decision-Making Model aiming at analyzing the characteristics and efficiency influence factors in a generic certification process. This model is developed from a dynamic operational perspective by viewing the certification process as an evidence–confidence conversion process. The proposed model is then applied to previous nuclear digital I and C certification experiences to successfully explain why some cases were successful and some were troublesome. Lessons learned from these cases provide invaluable insights regarding to the regulatory review activity. Furthermore, to utilize the insights obtained from the model, a prototype of a computer-aided licensing support system has been developed to speed up review evidence preparation and manipulation; thus, regulatory review efficiency can be further improved.

  12. High-performance digital triggering system for phase-controlled rectifiers

    International Nuclear Information System (INIS)

    Olsen, R.E.

    1983-01-01

    The larger power supplies used to power accelerator magnets are most commonly polyphase rectifiers using phase control. While this method is capable of handling impressive amounts of power, it suffers from one serious disadvantage, namely that of subharmonic ripple. Since the stability of the stored beam depends to a considerable extent on the regulation of the current in the bending magnets, subharmonic ripple, especially that of low frequency, can have a detrimental effect. At the NSLS, we have constructed a 12-pulse, phase control system using digital signal processing techniques that essentially eliminates subharmonic ripple

  13. Probabilistic risk assessment modeling of digital instrumentation and control systems using two dynamic methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Aldemir, T., E-mail: aldemir.1@osu.ed [Ohio State University, Nuclear Engineering Program, Columbus, OH 43210 (United States); Guarro, S. [ASCA, Inc., 1720 S. Catalina Avenue, Suite 220, Redondo Beach, CA 90277-5501 (United States); Mandelli, D. [Ohio State University, Nuclear Engineering Program, Columbus, OH 43210 (United States); Kirschenbaum, J. [Ohio State University, Department of Computer Science and Engineering, Columbus, OH 43210 (United States); Mangan, L.A. [Ohio State University, Nuclear Engineering Program, Columbus, OH 43210 (United States); Bucci, P. [Ohio State University, Department of Computer Science and Engineering, Columbus, OH 43210 (United States); Yau, M. [ASCA, Inc., 1720 S. Catalina Avenue, Suite 220, Redondo Beach, CA 90277-5501 (United States); Ekici, E. [Ohio State University, Department of Electrical and Computer Engineering, Columbus, OH 43210 (United States); Miller, D.W.; Sun, X. [Ohio State University, Nuclear Engineering Program, Columbus, OH 43210 (United States); Arndt, S.A. [U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001 (United States)

    2010-10-15

    The Markov/cell-to-cell mapping technique (CCMT) and the dynamic flowgraph methodology (DFM) are two system logic modeling methodologies that have been proposed to address the dynamic characteristics of digital instrumentation and control (I and C) systems and provide risk-analytical capabilities that supplement those provided by traditional probabilistic risk assessment (PRA) techniques for nuclear power plants. Both methodologies utilize a discrete state, multi-valued logic representation of the digital I and C system. For probabilistic quantification purposes, both techniques require the estimation of the probabilities of basic system failure modes, including digital I and C software failure modes, that appear in the prime implicants identified as contributors to a given system event of interest. As in any other system modeling process, the accuracy and predictive value of the models produced by the two techniques, depend not only on the intrinsic features of the modeling paradigm, but also and to a considerable extent on information and knowledge available to the analyst, concerning the system behavior and operation rules under normal and off-nominal conditions, and the associated controlled/monitored process dynamics. The application of the two methodologies is illustrated using a digital feedwater control system (DFWCS) similar to that of an operating pressurized water reactor. This application was carried out to demonstrate how the use of either technique, or both, can facilitate the updating of an existing nuclear power plant PRA model following an upgrade of the instrumentation and control system from analog to digital. Because of scope limitations, the focus of the demonstration of the methodologies was intentionally limited to aspects of digital I and C system behavior for which probabilistic data was on hand or could be generated within the existing project bounds of time and resources. The data used in the probabilistic quantification portion of the

  14. A cell-to-cell Markovian model for the reliability of a digital control system of a steam generator

    International Nuclear Information System (INIS)

    Gomes, Ian B.; Melo, Paulo F.F. Frutuoso e; Saldanha, Pedro L.C.

    2013-01-01

    With the shift of technology from analog to digital systems, due to the obsolescence of the older analog systems and the functional advantages of the digital ones, existing nuclear power plants have begun to replace their systems, while newer plants use digital systems from the beginning of their construction. However, the process of risk-informed analysis for digital systems has not been satisfactorily developed yet. Traditional methods, such as fault trees, have limitations, while dynamic methods are still in the tests stage and may be difficult to be applied to a real size probabilistic safety assessment (PSA) model. The objective of this paper is to study and obtain a better comprehension of the Markov/CCMT method, a method that combines the traditional Markovian methodology with the cell-to-cell mapping technique for representing the possible failure events that can be originated in the dynamic interactions between the instrumentation and control system and the controlled process, and among the various components of the digital system. The study consists of the simulation of a digital water level control system of the steam generator of a PWR plant. From this simulation, a Failure Modes and Effects Analysis (FMEA) was made and the information obtained was used to calculate the system reliability, using the Markov/CCMT methodology. The results show that the method is capable of identifying the most probable causes for a possible failure of the digital system. (author)

  15. Performance of automatic exposure control of digital imaging systems in three big hospitals

    International Nuclear Information System (INIS)

    Avramova-Cholakova, S.; Dyakov, I.

    2012-01-01

    The digital imaging systems are quite new in Bulgaria and there is still no clear evidence between all the servicing companies how to set the automatic exposure control (AEC) of the systems. The aim of this work is to study the AEC settings of the digital imaging systems in three big hospitals, serviced by different engineering companies. This study included seven systems, one with digital radiography (DR) and the others with computed radiography (CR) detectors. The AEC settings were tested in terms of mean pixel value (MPV), air kerma at phantom exit and detector dose indicator (DDI) dependence from AEC chamber selection, tube voltage and phantom thickness. Relatively small variations in MPV up to 8 % were observed for 4 of the CR systems, usually with small variations in DDI as well (except for one system, for which up to 40 % difference in DDI consistency between chambers was found). Air kerma at phantom exit for these systems had bigger variations up to 29 %. The other CR systems had big variations in MPV up to 57 % with DDI variations up to 30 % while air kerma changes were not small - from 8 to 38 %. The DR system showed smaller variation in air kerma at phantom exit up to 8 % and bigger variations in MPV and DDI up to 20 % and 15 % respectively. There is no systematic approach in the AEC settings used in the 3 hospitals. Further investigation and collaboration with the servicing companies is needed aiming to establish the optimized selection of AEC calibration parameters in each case. (authors)

  16. Digital base-band rf control system for the superconducting Darmstadt electron linear accelerator

    Directory of Open Access Journals (Sweden)

    M. Konrad

    2012-05-01

    Full Text Available The accelerating field in superconducting cavities has to be stabilized in amplitude and phase by a radio-frequency (rf control system. Because of their high loaded quality factor superconducting cavities are very susceptible for microphonics. To meet the increased requirements with respect to accuracy, availability, and diagnostics, the previous analog rf control system of the superconducting Darmstadt electron linear accelerator S-DALINAC has been replaced by a digital rf control system. The new hardware consists of two components: An rf module that converts the signal from the cavity down to the base-band and a field-programmable gate array board including a soft CPU that carries out the signal processing steps of the control algorithm. Different algorithms are used for normal-conducting and superconducting cavities. To improve the availability of the control system, techniques for automatic firmware and software deployment have been implemented. Extensive diagnostic features provide the operator with additional information. The architecture of the rf control system as well as the functionality of its components will be presented along with measurements that characterize the performance of the system, yielding, e.g., an amplitude stabilization down to (ΔA/A_{rms}=7×10^{-5} and a phase stabilization of (Δϕ_{rms}=0.8° for superconducting cavities.

  17. Description and Flight Test Results of the NASA F-8 Digital Fly-by-Wire Control System

    Science.gov (United States)

    1975-01-01

    A NASA program to develop digital fly-by-wire (DFBW) technology for aircraft applications is discussed. Phase I of the program demonstrated the feasibility of using a digital fly-by-wire system for aircraft control through developing and flight testing a single channel system, which used Apollo hardware, in an F-8C airplane. The objective of Phase II of the program is to establish a technology base for designing practical DFBW systems. It will involve developing and flight testing a triplex digital fly-by-wire system using state-of-the-art airborne computers, system hardware, software, and redundancy concepts. The papers included in this report describe the Phase I system and its development and present results from the flight program. Man-rated flight software and the effects of lightning on digital flight control systems are also discussed.

  18. DCS (Digital Control System) application of three generations; Aplicacao de um SDCD (Sistemas Digitais de Controle Distribuido) de tres geracoes

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Celso Roberto Molinaro [PETROBRAS S.A., Sao Jose dos Campos, SP (Brazil). Refinaria Henrique Lage (REVAP)

    2004-07-01

    Digital Control System are three generations of hardware and software platforms in process automation , but DCS is using the same functions and presents the reliability and availability . The challenge in automation has to maintain the old and the newest system operating and integrated perhaps the different times of platforms to guarantee the actual investments and in the future. A new generation of DCS using field equipment to control or the actual architecture with a lot of new information are coming with the technologies. (author)

  19. Computer based plant display and digital control system of Wolsong NPP Tritium Removal Facility

    International Nuclear Information System (INIS)

    Jung, C.; Smith, B.; Tosello, G.; Grosbois, J. de; Ahn, J.

    2007-01-01

    The Wolsong Tritium Removal Facility (WTRF) is an AECL-designed, first-of-a-kind facility that removes tritium from the heavy water that is used in systems of the CANDUM reactors in operation at the Wolsong Nuclear Power Plant in South Korea. The Plant Display and Control System (PDCS) provides digital plant monitoring and control for the WTRF and offers the advantages of state-of-the-art digital control system technologies for operations and maintenance. The overall features of the PDCS will be described and some of the specific approaches taken on the project to save construction time and costs, to reduce in-service life-cycle costs and to improve quality will be presented. The PDCS consists of two separate computer sub-systems: the Digital Control System (DCS) and the Plant Display System (PDS). The PDS provides the computer-based Human Machine Interface (HMI) for operators, and permits efficient supervisory or device level monitoring and control. A System Maintenance Console (SMC) is included in the PDS for the purpose of software and hardware configuration and on-line maintenance. A Historical Data System (HDS) is also included in the PDS as a data-server that continuously captures and logs process data and events for long-term storage and on-demand selective retrieval. The PDCS of WTRF has been designed and implemented based on an off-the-self PDS/DCS product combination, the Delta-V System from Emerson. The design includes fully redundant Ethernet network communications, controllers, power supplies and redundancy on selected I/O modules. The DCS provides field bus communications to interface with 3rd party controllers supplied on specialized skids, and supports HART communication with field transmitters. The DCS control logic was configured using a modular and graphical approach. The control strategies are primarily device control modules implemented as autonomous control loops, and implemented using IEC 61131-3 Function Block Diagram (FBD) and Structured

  20. New digital control system for the operation of the Colombian research reactor IAN-R1

    International Nuclear Information System (INIS)

    Celis del A, L.; Rivero, T.; Bucio, F.; Ramirez, R.; Segovia, A.; Palacios, J.

    2015-09-01

    En 2011, Mexico won the Colombian international tender for the renewal of instrumentation and control of the IAN-R1 Reactor, to Argentina and the United States. This paper presents the design criteria and the development made for the new digital control system installed in the Colombian nuclear reactor IAN-R1, which is based on a redundant and diverse architecture, which provides increased availability, reliability and safety in the reactor operation. This control system and associated instrumentation met all national export requirements, with the safety requirements established by the IAEA as well as the requirements demanded by the Colombian Regulatory Body in nuclear matter. On August 20, 2012, the Colombian IAN-R1 reactor reached its first criticality controlled with the new system developed at Instituto Nacional de Investigaciones Nucleares (ININ). On September 14, 2012, the new control system of the Colombian IAN-R1 reactor was officially handed over to the Colombian authorities, this being the first time that Mexico exported nuclear technology through the ININ. Currently the reactor is operating successfully with the new control system, and has an operating license for 5 years. (Author)

  1. Integrated digital control and man-machine interface for complex remote handing systems

    International Nuclear Information System (INIS)

    Rowe, J.C.; Spille, R.F.; Zimmermann, S.D.

    1987-01-01

    The Advanced Integrated Maintenance System (AIMS) is part of a continuing effort within the Consolidated Fuel Reprocessing Program at Oak Ridge National Laboratory to develop and extend the capabilities of remote manipulation and maintenance technology. The AIMS is a totally integrated approach to remote handling in hazardous environments. State-of-the-art computer systems connected through a high-speed distributed control system that supports the flexibility and expandability needed for large integrated maintenance applications. A man-Machine Interface provides high-level human interaction through a powerful color graphics menu-controlled operator console. An auxiliary control system handles the real-time processing needs for a variety of support hardware. A pair of dedicated fiber-optic-linked master/slave computer systems control the Advanced Servomanipulator master/slave arms using powerful distributed digital processing methods. The FORTH language was used as a real-time operating and development environment for the entire system, and all of these components are integrated into a control room concept that represents the latest advancements in the development of remote maintenance facilities for hazardous environments

  2. Integrated digital control and man-machine interface for complex remote handling systems

    International Nuclear Information System (INIS)

    Rowe, J.C.; Spille, R.F.; Zimmermann, S.D.

    1986-12-01

    The Advanced Integrated Maintenance System (AIMS) is part of a continuing effort within the Consolidated Fuel Reprocessing Program at Oak Ridge National Laboratory to develop and extend the capabilities of remote manipulation and maintenance technology. The AIMS is a totally integrated approach to remote handling in hazardous environments. State-of-the-art computer systems connected through a high-speed communication network provide a real-time distributed control system that supports the flexibility and expandability needed for large integrated maintenance applications. A Man-Machine Interface provides high-level human interaction through a powerful color graphics menu-controlled operator console. An auxiliary control system handles the real-time processing needs for a variety of support hardware. A pair of dedicated fiber-optic-linked master/slave computer system control the Advanced Servomanipulator master/slave arms using powerful distributed digital processing methods. The FORTH language was used as a real-time operating and development environment for the entire system, and all of these components are integrated into a control room concept that represents the latest advancements in the development of remote maintenance facilities for hazardous environments

  3. Attack tree based cyber security analysis of nuclear digital instrumentation and control systems

    International Nuclear Information System (INIS)

    Khand, P.A.

    2009-01-01

    To maintain the cyber security, nuclear digital Instrumentation and Control (I and C) systems must be analyzed for security risks because a single security breach due to a cyber attack can cause system failure, which can have catastrophic consequences on the environment and staff of a Nuclear Power Plant (NPP). Attack trees have been widely used to analyze the cyber security of digital systems due to their ability to capture system specific as well as attacker specific details. Therefore, a methodology based on attack trees has been proposed to analyze the cyber security of the systems. The methodology has been applied for the Cyber Security Analysis (CSA) of a Bistable Processor (BP) of a Reactor Protection System (RPS). Threats have been described according to their source. Attack scenarios have been generated using the attack tree and possible counter measures according to the Security Risk Level (SRL) of each scenario have been suggested. Moreover, cyber Security Requirements (SRs) have been elicited, and suitability of the requirements has been checked. (author)

  4. Analog-to-digital conversion of spectrometric data in information-control systems of activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mamonov, E I

    1972-01-01

    Analog-digital conversion (ADC) techniques in nuclear radiation spectrometer channels is a most important link of information control systems in activation analysis. For the development of the ADC of spectrometer channels logico-structural methods of increasing the capacity, procedures for boosting frequency modes and improving the accuracy are promising. Procedures are suggested for increasing the ADC capacity. Insufficient stability and noticeable non-linearity of the spectrometer channel can be corrected at the information processing stage if their regularities are known. Capacity limitations make the development of ADC featuring high stability, capacity and linearity quite urgent.

  5. A review of automatic exposure control of conventional and digital systems

    International Nuclear Information System (INIS)

    Workman, A.; Cowen, A.R.

    1989-01-01

    The desirable properties and methods of achieving automatic exposure control in film-screen radiography, fluoroscopy, spot-film fluorography and cinefluorography are discussed. Advantages of certain methods in achieving optimum image quality for minimal patient exposure are considered. In digital subtraction fluorography (DSF) where relatively large exposure levels per image are used, proper set-up of exposure conditions is of particular importance. These systems require a high degree of stability in exposure to maintain a high level of image quality. We have developed test methods for monitoring the set-up and reproducibility of exposure levels in DSF. (author)

  6. Programmable Digital Controller

    Science.gov (United States)

    Wassick, Gregory J.

    2012-01-01

    An existing three-channel analog servo loop controller has been redesigned for piezoelectric-transducer-based (PZT-based) etalon control applications to a digital servo loop controller. This change offers several improvements over the previous analog controller, including software control over proportional-integral-derivative (PID) parameters, inclusion of other data of interest such as temperature and pressure in the control laws, improved ability to compensate for PZT hysteresis and mechanical mount fluctuations, ability to provide pre-programmed scanning and stepping routines, improved user interface, expanded data acquisition, and reduced size, weight, and power.

  7. Conceptual design of a digital control system for nuclear criticality experiments

    International Nuclear Information System (INIS)

    Rojas, S.P.

    1994-04-01

    Nuclear criticality is a concern in many areas of nuclear engineering including waste management, nuclear weapons testing and design, basic nuclear research, and nuclear reactor design and analysis. As in many areas of science and engineering, experimental work conducted in this field has provided a wealth of data and insight essential to the formulation of theory and the advancement in knowledge of fissioning systems. In light of the many diverse applications of nuclear criticality, there is a continuing interest to learn and understand more about the fundamental physical processes through continued experimentation. This thesis addresses the problem of setting up and programming a microprocessor-based digital control system (PLC) for a proposed critical experiment using, among other devices, a stepper motor, a joystick control mechanism, and switches. This experiment represents a revised configuration to test cylindrical nuclear waste packages. A Monte Carlo numerical study for the proposed critical assembly has been performed in order to illustrate how results from numerical calculations are used in the process of assembling the control system and to corroborate previous experimental data. In summary, a control system utilizing some common devices necessary to perform a critical experiment (stepper motor, push-buttons, etc.) has been assembled. Control components were sized using the results of a probabilistic computer code (MCNP). Finally, a program was written that illustrates the coupling between the hardware and the devices being controlled in the new test fixture

  8. An integrated model for reliability estimation of digital nuclear protection system based on fault tree and software control flow methodologies

    International Nuclear Information System (INIS)

    Kim, Man Cheol; Seong, Poong Hyun

    2000-01-01

    In the nuclear industry, the difficulty of proving the reliabilities of digital systems prohibits the widespread use of digital systems in various nuclear application such as plant protection system. Even though there exist a few models which are used to estimate the reliabilities of digital systems, we develop a new integrated model which is more realistic than the existing models. We divide the process of estimating the reliability of a digital system into two phases, a high-level phase and a low-level phase, and the boundary of two phases is the reliabilities of subsystems. We apply software control flow method to the low-level phase and fault tree analysis to the high-level phase. The application of the model to Dynamic Safety System(DDS) shows that the estimated reliability of the system is quite reasonable and realistic

  9. An integrated model for reliability estimation of digital nuclear protection system based on fault tree and software control flow methodologies

    International Nuclear Information System (INIS)

    Kim, Man Cheol; Seong, Poong Hyun

    2000-01-01

    In nuclear industry, the difficulty of proving the reliabilities of digital systems prohibits the widespread use of digital systems in various nuclear application such as plant protection system. Even though there exist a few models which are used to estimate the reliabilities of digital systems, we develop a new integrated model which is more realistic than the existing models. We divide the process of estimating the reliability of a digital system into two phases, a high-level phase and a low-level phase, and the boundary of two phases is the reliabilities of subsystems. We apply software control flow method to the low-level phase and fault tree analysis to the high-level phase. The application of the model of dynamic safety system (DSS) shows that the estimated reliability of the system is quite reasonable and realistic. (author)

  10. Experience with digital instrumentation and control systems for CANDU power plant modifications

    International Nuclear Information System (INIS)

    Basu, S.

    1997-01-01

    Over the last years, Ontario Hydro CANDU power plants have gone through many modifications. This includes modification from analog hardwired controls to digital and solid state controls and replacement of the existing digital controls with the latest hardware and software technology. Examples of digital modifications at Bruce A and other CANDU power plants are briefly described and categorized. Most of the I and C technology development has been supported by the CANDU Owners Group (COG) a consortium of Canadian nuclear utilities and the Atomic Energy Canada Limited (AECL). (author)

  11. Experience with digital instrumentation and control systems for CANDU power plant modifications

    Energy Technology Data Exchange (ETDEWEB)

    Basu, S [Ontario Hydro, Toronto, ON (Canada)

    1997-07-01

    Over the last years, Ontario Hydro CANDU power plants have gone through many modifications. This includes modification from analog hardwired controls to digital and solid state controls and replacement of the existing digital controls with the latest hardware and software technology. Examples of digital modifications at Bruce A and other CANDU power plants are briefly described and categorized. Most of the I and C technology development has been supported by the CANDU Owners Group (COG) a consortium of Canadian nuclear utilities and the Atomic Energy Canada Limited (AECL). (author).

  12. Digital communication system

    Science.gov (United States)

    Monford, L. G., Jr. (Inventor)

    1974-01-01

    A digital communication system is reported for parallel operation of 16 or more transceiver units with the use of only four interconnecting wires. A remote synchronization circuit produces unit address control words sequentially in data frames of 16 words. Means are provided in each transceiver unit to decode calling signals and to transmit calling and data signals. The transceivers communicate with each other over one data line. The synchronization unit communicates the address control information to the transceiver units over an address line and further provides the timing information over a clock line. A reference voltage level or ground line completes the interconnecting four wire hookup.

  13. Qualification of the flight-critical AFTI/F-16 digital flight control system. [Advanced Fighter Technology Integration

    Science.gov (United States)

    Mackall, D. A.; Ishmael, S. D.; Regenie, V. A.

    1983-01-01

    Qualification considerations for assuring the safety of a life-critical digital flight control system include four major areas: systems interactions, verification, validation, and configuration control. The AFTI/F-16 design, development, and qualification illustrate these considerations. In this paper, qualification concepts, procedures, and methodologies are discussed and illustrated through specific examples.

  14. Matlab/Simulink-based simulation for digital-control system of marine three-shaft gas-turbine

    International Nuclear Information System (INIS)

    Yu Youhong; Chen Lingen; Sun Fengrui; Wu Chih

    2005-01-01

    A gas-turbine plant model is required in order to design and develop its control system. In this paper, a simulation model of a marine three-shaft gas-turbine's digital-control system is presented. Acceleration processes are simulated via a Matlab/Simulink program. The effects of some of the main variables on the system's performance are analyzed and the optimum values of parameters obtained. A simulation experiment upon a real gas-turbine plant is performed using the digital-control model. The results show that the simulation model is reliable

  15. Assessment of wireless Sensor Networks for Digital Instrument and Control System at Nuclear Facilities

    International Nuclear Information System (INIS)

    Gomma, R.I.M.

    2015-01-01

    Instrumentation and Control (I and C) systems play a crucial role in the operation of Nuclear Power Plants (NPPs). The most important task of I and C systems is to ensure safety, availability, and performance of the plant. The advanced generation of NPP design is expected to have the higher degree of automation; consequently, it requires new solutions in both sensing technologies and digital control. In general, the world’s nuclear power fleet is relying on the progress of digital electronics and information technology, to create incentives for integrated replacement of traditional analog electronics with novel digital I and C systems that rely on wireless technology. Moreover, as the domain of Wireless Sensor Networks (WSN) increases its market share in many industrial, health, and critical applications, it has matured significantly. As a result, the barriers to the nuclear industry entry will surely continue to decrease further. Nowadays, several WSN deployments for on-line monitoring of the nuclear environment have been recently addressed by incremental and experimental networks. Furthermore, upon tightening new regulations, the demand for using smart wireless sensing for safety, and surveillance applications of nuclear installations are growing rapidly. The first part of this thesis describes the design of a practical small-scale WSN that allows smart real-time monitoring of radiation levels at nuclear facilities. A wireless system combined with a radiation sensor and associated peripherals been developed and implemented on ZigBee technology using the TI CC2530 chip. The radiation sensor uses a Geiger Muller Tube (GMT) as a reliable detector for the radioactive particulates in the gaseous effluent vented from nuclear facilities. The WSN allows the operators to record and control the radiation levels emitted into the environment, and it is supported by a warning system, for the early detection of radiation release. We evaluated the performance of the radiation

  16. An analysis of Technical Security Control Requirements For Digital I and C Systems in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Song, Jaegu; Lee, Jungwoon; Park, Geeyong; Kwon, Keechoon; Lee, Dongyoung; Lee, Cheolkwon

    2013-01-01

    Instrumentation and control systems in nuclear power plants have been digitalized for the purpose of maintenance and precise operation. This digitalization, however, brings out issues related to cyber security. In the most recent past, international standard organizations, regulatory institutes, and research institutes have performed a number of studies addressing these systems cyber security. In order to provide information helpful to the system designers in their application of cyber security for the systems, this paper presents methods and considerations to define attack vectors in a target system, to review and select the requirements in the Regulatory Guide 5.71, and to integrate the results to identify applicable technical security control requirements. In this study, attack vectors are analyzed through the vulnerability analyses and penetration tests with a simplified safety system, and the elements of critical digital assets acting as attack vectors are identified. Among the security control requirements listed in Appendices B and C to Regulatory Guide 5.71, those that should be implemented into the systems are selected and classified in groups of technical security control requirements using the results of the attack vector analysis. For the attack vector elements of critical digital assets, all the technical security control requirements are evaluated to determine whether they are applicable and effective, and considerations in this evaluation are also discussed. The technical security control requirements in three important categories of access control, monitoring and logging, and encryption are derived and grouped according to the elements of attack vectors as results for the sample safety system

  17. An analysis of Technical Security Control Requirements For Digital I and C Systems in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jaegu; Lee, Jungwoon; Park, Geeyong; Kwon, Keechoon; Lee, Dongyoung; Lee, Cheolkwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    Instrumentation and control systems in nuclear power plants have been digitalized for the purpose of maintenance and precise operation. This digitalization, however, brings out issues related to cyber security. In the most recent past, international standard organizations, regulatory institutes, and research institutes have performed a number of studies addressing these systems cyber security. In order to provide information helpful to the system designers in their application of cyber security for the systems, this paper presents methods and considerations to define attack vectors in a target system, to review and select the requirements in the Regulatory Guide 5.71, and to integrate the results to identify applicable technical security control requirements. In this study, attack vectors are analyzed through the vulnerability analyses and penetration tests with a simplified safety system, and the elements of critical digital assets acting as attack vectors are identified. Among the security control requirements listed in Appendices B and C to Regulatory Guide 5.71, those that should be implemented into the systems are selected and classified in groups of technical security control requirements using the results of the attack vector analysis. For the attack vector elements of critical digital assets, all the technical security control requirements are evaluated to determine whether they are applicable and effective, and considerations in this evaluation are also discussed. The technical security control requirements in three important categories of access control, monitoring and logging, and encryption are derived and grouped according to the elements of attack vectors as results for the sample safety system.

  18. Verification of failover effects from distributed control system communication networks in digitalized nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Min, Moon Gi; Lee, Jae Ki; Lee, Kwang Hyun; Lee, Dong Il; Lim, Hee Taek [Korea Hydro and Nuclear Power Co., Ltd, Daejeon (Korea, Republic of)

    2017-08-15

    Distributed Control System (DCS) communication networks, which use Fast Ethernet with redundant networks for the transmission of information, have been installed in digitalized nuclear power plants. Normally, failover tests are performed to verify the reliability of redundant networks during design and manufacturing phases; however, systematic integrity tests of DCS networks cannot be fully performed during these phases because all relevant equipment is not installed completely during these two phases. In additions, practical verification tests are insufficient, and there is a need to test the actual failover function of DCS redundant networks in the target environment. The purpose of this study is to verify that the failover functions works correctly in certain abnormal conditions during installation and commissioning phase and identify the influence of network failover on the entire DCS. To quantify the effects of network failover in the DCS, the packets (Protocol Data Units) must be collected and resource usage of the system has to be monitored and analyzed. This study introduces the use of a new methodology for verification of DCS network failover during the installation and commissioning phases. This study is expected to provide insight into verification methodology and the failover effects from DCS redundant networks. It also provides test results of network performance from DCS network failover in digitalized domestic nuclear power plants (NPPs)

  19. F-16XL ship #1 (#849) during first flight of the Digital Flight Control System (DFCS)

    Science.gov (United States)

    1997-01-01

    After completing its first flight with the Digital Flight Control System on December 16, 1997, the F-16XL #1 aircraft began a series of envelope expansion flights. On January 27 and 29, 1998, it successfully completed structural clearance tests, as well as most of the load testing Only flights at Mach 1.05 at 10,000 feet, Mach 1.1 at 15,000 feet, and Mach 1.2 at 20,000 feet remained. During the next flight, on February 4, an instrumentation problem cut short the planned envelope expansion tests. After the problem was corrected, the F-16XL returned to flight status, and on February 18 and 20, flight control and evaluation flights were made. Two more research flights were planned for the following week, but another problem appeared. During the ground start up, project personnel noticed that the leading edge flap moved without being commanded. The Digital Flight Control Computer was sent to the Lockheed-Martin facility at Fort Worth, where the problem was traced to a defective chip in the computer. After it was replaced, the F-16XL #1 flew a highly successful flight controls and handling qualities evaluation flight on March 26, clearing the way for the final tests. The final limited loads expansion flight occurred on March 31, and was fully successful. As a result, the on-site Lockheed-Martin loads engineer cleared the aircraft to Mach 1.8. The remaining two handling qualities and flight control evaluation flights were both made on April 3, 1998. These three flights concluded the flight test portion of the DFCS upgrade.

  20. Probabilistic safety assessment for digital instrumentation and control systems in nuclear power plants - a review

    International Nuclear Information System (INIS)

    Lu, L.; Jiang, J.

    2003-01-01

    Deregulation in electricity market has created a great deal of challenges for nuclear power industries [1]. To stay competitive, Nuclear Power Plants (NPPs) will have to find ways to reduce their operational costs and to improve the plant safety. Instrumentation and Control (I and C) systems play an important role in this regard. Thus, new methodologies need to be developed to manage the operation of I and C systems more economically without jeopardizing the overall plant safety. Probabilistic Safety Assessment (PSA) technique is one of the promising methods to deal with such an issue, because PSA analyzes various system operational issues from a probabilistic sense, rather than a worst-case approach. However, there are several limitations when PSA is applied to I and C systems directly. A possible solution to this problem can be found by incorporating PSA with several other approaches. To better understand the issues involved, an attempt has been made in this paper to carry out a literature survey on this and related subject, particularly the effort will be made on: 1) the development of digital I and C systems in NPP, 2) PSA and its potential benefits and limitations, and 3) applications of PSA in various aspects of I and C systems including the resource allocation, the determination of surveillance testing strategies and the design of I and C systems. Finally, some solutions to overcome the aforementioned obstacles when applying PSA in I and C systems are also examined critically. (author)

  1. Analogue to digital upgrade project-boiler feedwater control system for Bruce Power nuclear units 1 & 2

    International Nuclear Information System (INIS)

    Long, R.

    2012-01-01

    Bruce Power Nuclear Generating Station A, “Bruce A” is in the final stages of its Restart Project. This capital project will see a large scale rehabilitation of Units 1 and 2 resulting in addition of 1500MW of safe, reliable, clean electricity to the Ontario grid. Restart Project Scope 375, Boiler Feedwater Controls Upgrade was sanctioned to replace obsolete analog devices with a modern digital control system. This project replaced the existing Foxboro H Line analog controls which comprised of 81 individual control modules and support instrumentation. The replacement system was a Triconex Triple Modular Redundant PLC which interfaces with two redundant touch screen monitors. The upgraded digital system incorporates the following controls: 1. Boiler Level Control Loops 2. Dearator Level Control Loops 3. Dearator Pressure Control Loops 4. Boiler Feedwater Recirculation Flow Control Loops A number of technical challenges were addressed when installing a new digital system within the existing plant configuration. Interfaces to new, old and refurbished field devices must be understood as well as implications of connecting to the plant’s Digital Control Computers (DCC’s) and newly installed Steam Generators. The overall project involved many stakeholders to address various requirements from conceptual / design stage through procurement, construction, commissioning and return to service. In addition, the project highlighted the unique requirements found in Nuclear Industry with respect to Human Factors and Software Quality Assurance. (author)

  2. Cyber security level assignment for research reactor digital instrumentation and control system architecture using concept of defense in depth

    International Nuclear Information System (INIS)

    Shin, Jin Soo; Heo, Gyun Young; Son, Han Seong; Kim, Young Ki; Park, Jaek Wan

    2012-01-01

    Due to recent aging of the analog instrumentation of many nuclear power plants (NPPs) and research reactors, the system reliability decreases while maintenance and testing costs increase. In addition, it is difficult to find the substitutable analog equipment s due to obsolescence. Therefore, the instrumentation and control (I and C) systems have changed from analog system to digital system due to these facts. With the introduction of digital systems, research reactors are forced to care for the problem of cyber attacks because I and C systems have been digitalized using networks or communication systems. Especially, it is more issued at research reactors due to the accessibility of human resources. In the real world, an IBM researcher has been successful in controlling the software by penetrating a NPPs network in U.S. on July 2008 and acquiring the control right of nuclear facilities after one week. Moreover, the malignant code called 'stuxnet' impaired the nearly 1,000 centrifugal separators in Iran according to an IAEA report. The problem of cyber attacks highlights the important of cyber security, which should be emphasized. Defense.in.depth (DID) is a significant concept for the cyber security to work properly. DID institutes and maintains a hardy program for critical digital asset (CDA) by implementing multiple security boundaries. In this work, we assign cyber security levels to a typical digital I and C system using DID concept. This work is very useful in applying the concept of DID to nuclear industry with respect to cyber security

  3. Cyber security level assignment for research reactor digital instrumentation and control system architecture using concept of defense in depth

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jin Soo; Heo, Gyun Young [Kyung Hee University, Seoul (Korea, Republic of); Son, Han Seong [Joongbu Univ., Chungnam (Korea, Republic of); Kim, Young Ki; Park, Jaek Wan [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    Due to recent aging of the analog instrumentation of many nuclear power plants (NPPs) and research reactors, the system reliability decreases while maintenance and testing costs increase. In addition, it is difficult to find the substitutable analog equipment s due to obsolescence. Therefore, the instrumentation and control (I and C) systems have changed from analog system to digital system due to these facts. With the introduction of digital systems, research reactors are forced to care for the problem of cyber attacks because I and C systems have been digitalized using networks or communication systems. Especially, it is more issued at research reactors due to the accessibility of human resources. In the real world, an IBM researcher has been successful in controlling the software by penetrating a NPPs network in U.S. on July 2008 and acquiring the control right of nuclear facilities after one week. Moreover, the malignant code called 'stuxnet' impaired the nearly 1,000 centrifugal separators in Iran according to an IAEA report. The problem of cyber attacks highlights the important of cyber security, which should be emphasized. Defense.in.depth (DID) is a significant concept for the cyber security to work properly. DID institutes and maintains a hardy program for critical digital asset (CDA) by implementing multiple security boundaries. In this work, we assign cyber security levels to a typical digital I and C system using DID concept. This work is very useful in applying the concept of DID to nuclear industry with respect to cyber security.

  4. Parameters-adjustable front-end controller in digital nuclear measurement system

    International Nuclear Information System (INIS)

    Hao Dejian; Zhang Ruanyu; Yan Yangyang; Wang Peng; Tang Changjian

    2013-01-01

    Background: One digitizer is used to implement a digital nuclear measurement for the acquisition of nuclear information. Purpose: A principle and method of a parameter-adjustable front-end controller is presented for the sake of reducing the quantitative errors while getting the maximum ENOB (effective number of bits) of ADC (analog-to-digital converter) during waveform digitizing, as well as reducing the losing counts. Methods: First of all, the quantitative relationship among the radiation count rate (n), the amplitude of input signal (V in ), the conversion scale of ADC (±V) and the amplification factor (A) was derived. Secondly, the hardware and software of the front-end controller were designed to fulfill matching the output of different detectors, adjusting the amplification linearly through the control of channel switching, and setting of digital potentiometer by CPLD (Complex Programmable Logic Device). Results: (1) Through the measurement of γ-ray of Am-241 under our digital nuclear measurement set-up with CZT detector, it was validated that the amplitude of output signal of detectors of RC feedback type could be amplified linearly with adjustable amplification by the front-end controller. (2) Through the measurement of X-ray spectrum of Fe-5.5 under our digital nuclear measurement set-up with Si-PIN detector, it was validated that the front-end controller was suitable for the switch resetting type detectors, by which high precision measurement under various count rates could be fulfilled. Conclusion: The principle and method of the parameter-adjustable front-end controller presented in this paper is correct and feasible. (authors)

  5. Digital control programmer for temperature control

    International Nuclear Information System (INIS)

    Rajore, S.B.; Kumar, S.V.

    1993-01-01

    This report describes a PC based digital control programmer for controlling and programming temperature of a high vacuum resistance heating furnace and the software developed to control power using PID algorithm. It also describes the amplifier specially developed to suit the input requirement of the non-standard W5 thermocouple and the software and hardware protections introduced in the system. (author). 5 refs., 8 figs., 1 appendix

  6. Proposal of digital interface for the system of the air conditioner's remote control: analysis of the system of feedback.

    Science.gov (United States)

    da Silva de Queiroz Pierre, Raisa; Kawada, Tarô Arthur Tavares; Fontes, André Guimarães

    2012-01-01

    Develop a proposal of digital interface for the system of the remote control, that functions as support system during the manipulation of air conditioner adjusted for the users in general, from ergonomic parameters, objectifying the reduction of the problems faced for the user and improving the process. 20 people with questionnaire with both qualitative and quantitative level. Linear Method consists of a sequence of steps in which the input of one of them depends on the output from the previous one, although they are independent. The process of feedback, when necessary, must occur within each step separately.

  7. Gallium arsenide digital integrated circuits for controlling SLAC CW-RF systems

    International Nuclear Information System (INIS)

    Ronan, M.T.; Lee, K.L.; Corredoura, P.; Judkins, J.G.

    1989-01-01

    In order to fill the PEP and SPEAR storage rings with beams from the SLC linac and damping rings, precise control of the linac subharmonic buncher and the damping ring RF is required. Recently several companies have developed resettable GaAs master/slave D-type flip-flops which are capable of operating at frequencies of 3 GHz and higher. Using these digital devices as frequency dividers, one can phase shift the SLAC CW-RF systems to optimize the timing for filling the storage rings. The authors have evaluated the performance of integrated circuits from two vendors for our particular application. Using microstrip circuit techniques, they have built and operated in the accelerator several chassis to synchronize a reset signal from the storage rings to the SLAC 2.856 GHz RF and to phase shift divide-by-four and divide-by-sixteen frequency dividers to the nearest 350 psec bucket required for filling

  8. Guidelines for evaluating software configuration management plans for digital instrumentation and control systems

    International Nuclear Information System (INIS)

    Cheon, Se Woo; Park, Jong Kyun; Lee, Ki Young; Lee, Jang Soo; Kim, Jang Yeon

    2001-08-01

    Software configuration management (SCM) is the process for identifying software configuration items (CIs), controlling the implementation and changes to software, recording and reporting the status of changes, and verifying the completeness and correctness of the released software. SCM consists of two major aspects: planning and implementation. Effective SCM involves planning for how activities are to be performed, and performing these activities in accordance with the Plan. This report first reviews the background of SCM that include key standards, SCM disciplines, SCM basic functions, baselines, software entity, SCM process, the implementation of SCM, and the tools of SCM. In turn, the report provides the guidelines for evaluating the SCM Plan for digital I and C systems of nuclear power plants. Most of the guidelines in the report are based on IEEE Std 828 and ANSI/IEEE Std 1042. According to BTP-14, NUREG-0800, the evaluation topics on the SCM Plan is classified into three categories: management, implementation, and resource characteristics

  9. Technical Challenges in the Application and Licensing of Digital Instrumentation and Control Systems in Nuclear Power Plants

    International Nuclear Information System (INIS)

    2015-01-01

    With the modernization of existing analogue instrumentation and control (I&C) systems in nuclear power plants through digital I&C technology, and the implementation of digital I&C systems in new plants, the industry is faced with significant challenges. These challenges appear in the form of difficulties in managing the necessarily incremental transition, highly integrated (and interdependent) architectures, the flexible configurability enabled by digital technology, and uncertainty and inconsistency in licensing digital I&C systems and equipment in the different Member States. This publication discusses 17 major issues that utilities, developers, suppliers and regulatory stakeholders need to consider, so that the industry can capture and benefit from shared experience, recent technological developments, and emerging best practices

  10. Digital Distributed Control System Design: Control Policy for Shared Objects in HTR-PM

    International Nuclear Information System (INIS)

    Zhou Shuqiao; Huang Xiaojin

    2014-01-01

    HTR-PM is an HTR demonstration plant with a structure of two modules feeding one steam turbine. Compared with the structure of one single reactor feeding one turbine, there are more devices shared between these two modules. When they are operated, the shared components are prone to introduce collisions or even logical deadlocks for different technical processes. The future commercial HTR-PM plants are supposed to comprise more modules for a larger turbine, thus the collision problem introduced by the shared components may become severer. Therefore, how to design suitable policies in the distributed control system (DCS) to relieve the collisions during using these shared devices is a new and also a very important problem. In this paper, the classifications of the shared devices are first addressed, and then how to identify the shared objects of an NPP is proposed. Furthermore, a general model for the control logic design is proposed, taking into consideration the collision avoidance, time delay and fairness. The example of how to apply the schemes to relieve the conflicts and deadlocks in the processes of using the shared devices in fuel element cycling system is illustrated. (author)

  11. Centralized digital control of accelerators

    International Nuclear Information System (INIS)

    Melen, R.E.

    1983-09-01

    In contrasting the title of this paper with a second paper to be presented at this conference entitled Distributed Digital Control of Accelerators, a potential reader might be led to believe that this paper will focus on systems whose computing intelligence is centered in one or more computers in a centralized location. Instead, this paper will describe the architectural evolution of SLAC's computer based accelerator control systems with respect to the distribution of their intelligence. However, the use of the word centralized in the title is appropriate because these systems are based on the use of centralized large and computationally powerful processors that are typically supported by networks of smaller distributed processors

  12. Digital LLRF System for RFQ

    International Nuclear Information System (INIS)

    Agashe, Alok; Motiwala, P.D.; Bharade, S.K.; Mohan, Shyam; Joshi, Gopal; Das, D.

    2015-01-01

    A Low level RF (LLRF) system based on digital techniques has been developed for RFQ of Low Energy High Intensity Proton Accelerator (LEHIPA). The basic LLRF system for RFQ is composed of a Front end analog module housed in a 19 inch bin and a 6U cPCI based Digital board having a high speed and high density FPGA onboard, supporting 32 bit/33MHz PCI ver2.0 protocol and housed in a 19 inch cPCI crate. It also has a cPCI based CPU board with QNX operating system. The cPCI crate is connected to control room via Ethernet. Analog module conditions the input field signals from RF cavity and makes it compatible to digital board. It also amplifies RF Drive signal (Modulator output) from digital board, which goes to high power amplifier. The digital board digitally processes the input RF signals, and generates RF drive signal, which after amplification, used for driving the resonant cavity. The main features of digital board are under-sampling of input RF signals, digital in-phase and quadrature detection, and a proportional- integral (PI) controller algorithm implemented in a FPGA. The LLRF system works in CW as well as in PULSE mode. It also has a DDS implemented in VHDL, used for conditioning and tracking/tuning of the cavity. LLRF system operates under QNX based equipment frontend application and client running from control room. One analog module and one digital board set, supports one resonant cavity. The present paper describes the development of an LLRF system and its results with a test cavity. (author)

  13. Digital control card based on digital signal processor

    International Nuclear Information System (INIS)

    Hou Shigang; Yin Zhiguo; Xia Le

    2008-01-01

    A digital control card based on digital signal processor was developed. Two Freescale DSP-56303 processors were utilized to achieve 3 channels proportional- integral-differential regulations. The card offers high flexibility for 100 MeV cyclotron RF system development. It was used as feedback controller in low level radio frequency control prototype, with the feedback gain parameters continuously adjustable. By using high precision analog to digital converter with 500 kHz sampling rate, a regulation bandwidth of 20 kHz was achieved. (authors)

  14. Digital control rod blocking monitor

    International Nuclear Information System (INIS)

    Funayama, Yoshio.

    1996-01-01

    The present invention system is used for monitoring of a power region of a reactor, and used for monitoring of simultaneous withdrawal of a plurality of control rods without increasing the size or complicating the system. Namely, the system processes signals from a neutron flux detectors at the periphery of control rods controlled for withdrawal. As a result of the processing, the digital monitoring system generates an alarm when the reactor power at the periphery of the control rods fluctuates exceeding an allowable range. In the system, a control rod information forming means prepares frame data comprising front data, positions of the control rods to be withdrawn, frame numbers and completion data. A serial data transmitting means transmits the frame data successively as repeating frame data rows. A control rod information receiving means takes up the frame data of each of control rods to be withdrawn from the transmitted frame data rows. Since the system of the present invention can monitor the withdrawal of a plurality of control rods simultaneously without increasing the size or complicating the system, cost can be saved and the maintenance can be improved. (I.S.)

  15. Digital recording system

    International Nuclear Information System (INIS)

    Chandra, A.K.; Deshpande, S.V.; Iyer, A.; Vaidya, U.W.

    1987-01-01

    A large number of critical process parameters in nuclear power plants have hitherto been monitored using electromechanical chart recorders. The reducing costs of electronics systems have led to a trend towards modernizing power plant control rooms by computerizing all the panel instrumentation. As a first step, it has been decided to develop a digital recording system to record the values of 48 process parameters. The system as developed and described in this report is more than a replacement for recorders; it offers substantial advantages in terms of lower overall system cost, excellent time resolution, accurate data and absolute synchronization for correlated signals. The system provides high speed recording of 48 process parameters, maintains historical records and permits retrieval and display of archival information on a colour monitor, a plotter and a printer. It is implemented using a front end data acquisition unit connected on a serial link to a PC-XT computer with 20 MB Winchester. The system offers an extremely user friendly man machine interaction, based on a hierarchical paged menu driven scheme. Softwre development for this system has been carried out using the C language. (author). 9 figs

  16. Advanced digital instrumentation and control system for nuclear power plant protection

    Energy Technology Data Exchange (ETDEWEB)

    Sabino, D [VVER Engineering, Westinghouse Electric Corporation (United States)

    1998-12-31

    The Diverse Protection System is a back-up to the Primary Reactor Protection System developed for use at the Temelin nuclear power plant. The DPS is a digital system which provides a wealth of benefits from today`s advanced technology. These benefits include a compact hardware design with high performance microprocessors and a structured software design using a high level language. An overview of the DPS functions, hardware and software is provided. (author). 1 fig., 1 tab.

  17. An alternative method for noise analysis using pixel variance as part of quality control procedures on digital mammography systems.

    NARCIS (Netherlands)

    Bouwman, R.; Young, K.; Lazzari, B.; Ravaglia, V.; Broeders, M.J.M.; Engen, R. van

    2009-01-01

    According to the European Guidelines for quality assured breast cancer screening and diagnosis, noise analysis is one of the measurements that needs to be performed as part of quality control procedures on digital mammography systems. However, the method recommended in the European Guidelines does

  18. BROADBAND DIGITAL GEOPHYSICAL TELEMETRY SYSTEM.

    Science.gov (United States)

    Seeley, Robert L.; Daniels, Jeffrey J.

    1984-01-01

    A system has been developed to simultaneously sample and transmit digital data from five remote geophysical data receiver stations to a control station that processes, displays, and stores the data. A microprocessor in each remote station receives commands from the control station over a single telemetry channel.

  19. AN ANALYSIS OF TECHNICAL SECURITY CONTROL REQUIREMENTS FOR DIGITAL I&C SYSTEMS IN NUCLEAR POWER PLANTS

    Directory of Open Access Journals (Sweden)

    JAE-GU SONG

    2013-10-01

    Full Text Available Instrumentation and control systems in nuclear power plants have been digitalized for the purpose of maintenance and precise operation. This digitalization, however, brings out issues related to cyber security. In the most recent past, international standard organizations, regulatory institutes, and research institutes have performed a number of studies addressing these systems cyber security. In order to provide information helpful to the system designers in their application of cyber security for the systems, this paper presents methods and considerations to define attack vectors in a target system, to review and select the requirements in the Regulatory Guide 5.71, and to integrate the results to identify applicable technical security control requirements. In this study, attack vectors are analyzed through the vulnerability analyses and penetration tests with a simplified safety system, and the elements of critical digital assets acting as attack vectors are identified. Among the security control requirements listed in Appendices B and C to Regulatory Guide 5.71, those that should be implemented into the systems are selected and classified in groups of technical security control requirements using the results of the attack vector analysis. For the attack vector elements of critical digital assets, all the technical security control requirements are evaluated to determine whether they are applicable and effective, and considerations in this evaluation are also discussed. The technical security control requirements in three important categories of access control, monitoring and logging, and encryption are derived and grouped according to the elements of attack vectors as results for the sample safety system.

  20. Digital control of research reactors

    International Nuclear Information System (INIS)

    Crump, J.C. III.; Richards, W.J.; Heidel, C.C.

    1991-01-01

    Research reactors provide an important service for the nuclear industry. Developments and innovations used for research reactors can be later applied to larger power reactors. Their relatively inexpensive cost allows research reactors to be an excellent testing ground for the reactors of tomorrow. One area of current interest is digital control of research reactor systems. Digital control systems offer the benefits of implementation and superior system response over their analog counterparts. At McClellan Air Force Base in Sacramento, California, the Stationary Neutron Radiography System (SNRS) uses a 1,000-kW TRIGA reactor for neutron radiography and other nuclear research missions. The neutron radiography beams generated by the reactor are used to detect corrosion in aircraft structures. While the use of the reactor to inspect intact F-111 wings is in itself noteworthy, there is another area in which the facility has applied new technology: the instrumentation and control system (ICS). The ICS developed by General Atomics (GA) contains several new and significant items: (a) the ability to servocontrol on three rods, (b) the ability to produce a square wave, and (c) the use of a software configurator to tune parameters affected by the actual reactor core dynamics. These items will probably be present in most, if not all, future research reactors. They were developed with increased control and overall usefulness of the reactor in mind

  1. Digital systems to acquire radiological imaging. Characteristics and quality control; Sistemas digitales de adquisicion de imagenes radiograficas. Caracteristicas y Control de Calidad

    Energy Technology Data Exchange (ETDEWEB)

    Torres Cabrera, R.; Hernando Gonzalez, I.

    2006-07-01

    Due to its special characteristics, quality control in digital radiographic systems is very important, even more than in conventional film-screen systems. Differences between digital and analogical images,a in terms of dynamics range, spatial and contrast resolution, and the flexibility of data post-processing require some actions to maintain clinical images in an optimum quality level. Revision 1 of the Spanish Protocol of Quality Control in Diagnostic Radiology includes a chapter dedicated to the quality control of these digital systems for the acquisition of radiographic images. In this paper the different parameters for quality control procedures are described. Also some difficulties to be concerned about (absence of levels of tolerance, access to the raw-data images and related information, availability of use anthropomorphic phantoms, etc, etc) are noted, as well as the most significant aspects of the differences in relation to the ana logical systems. (Author) 15 refs.

  2. Use of a graphical user interface approach for digital and physical simulation in power systems control education

    International Nuclear Information System (INIS)

    Shoults, R.R.; Barrera-Cardiel, E.

    1992-01-01

    This paper presents the design of a laboratory with software and hardware structures for digital and physical simulation in the area of Power Systems Control Education. The hardware structure includes a special man-machine interface designed with a graphical user interface approach. This interface allows the user full control over the simulation and provides facilities for the study of the response of the simulated system. This approach is illustrated with the design of a control system for a physically based HVDC transmission system model

  3. Main control system verification and validation of NPP digital I and C system based on engineering simulator

    International Nuclear Information System (INIS)

    Lin Meng; Hou Dong; Liu Pengfei; Yang Zongwei; Yang Yanhua

    2010-01-01

    Full-scope digital instrumentation and controls system (I and C) technique is being introduced in Chinese new constructed Nuclear Power Plant (NPP), which mainly includes three parts: control system, reactor protection system and engineered safety feature actuation system. For example, SIEMENS TELEPERM XP and XS distributed control system (DCS) have been used in Ling Ao Phase II NPP, which is located in Guangdong province, China. This is the first NPP project in China that Chinese engineers are fully responsible for all the configuration of actual analog and logic diagram, although experience in NPP full-scope digital I and C is very limited. For the safety, it has to be made sure that configuration is right and control functions can be accomplished before the phase of real plant testing on reactor. Therefore, primary verification and validation (V and V) of I and C needs to be carried out. Except the common and basic way, i.e. checking the diagram configuration one by one according to original design, NPP engineering simulator is applied as another effective approach of V and V. For this purpose, a virtual NPP thermal-hydraulic model is established as a basis according to Ling Ao Phase II NPP design, and the NPP simulation tools can provide plant operation parameters to DCS, accept control signal from I and C and give response. During the test, one set of data acquisition equipments are used to build a connection between the engineering simulator (software) and SIEMENS DCS I/O cabinet (hardware). In this emulation, original diagram configuration in DCS and field hardware structures are kept unchanged. In this way, firstly judging whether there are some problems by observing the input and output of DCS without knowing the internal configuration. Then secondly, problems can be found and corrected by understanding and checking the exact and complex configuration in detail. At last, the correctness and functionality of the control system are verified. This method is

  4. Digital mineral logging system

    International Nuclear Information System (INIS)

    West, J.B.

    1980-01-01

    A digital mineral logging system acquires data from a mineral logging tool passing through a borehole and transmits the data uphole to an electronic digital signal processor. A predetermined combination of sensors, including a deviometer, is located in a logging tool for the acquisition of the desired data as the logging tool is raised from the borehole. Sensor data in analog format is converted in the logging tool to a digital format and periodically batch transmitted to the surface at a predetermined sampling rate. An identification code is provided for each mineral logging tool, and the code is transmitted to the surface along with the sensor data. The self-identifying tool code is transmitted to the digital signal processor to identify the code against a stored list of the range of numbers assigned to that type of tool. The data is transmitted up the d-c power lines of the tool by a frequency shift key transmission technique. At the surface, a frequency shift key demodulation unit transmits the decoupled data to an asynchronous receiver interfaced to the electronic digital signal processor. During a recording phase, the signals from the logging tool are read by the electronic digital signal processor and stored for later processing. During a calculating phase, the stored data is processed by the digital signal processor and the results are outputted to a printer or plotter, or both

  5. Gallium arsenide digital integrated circuits for controlling SLAC CW-RF systems

    International Nuclear Information System (INIS)

    Ronan, M.T.; Lee, K.L.; Corredoura, P.; Judkins, J.G.

    1988-10-01

    In order to fill the PEP and SPEAR storage rings with beams from the SLC linac and damping rings, precise control of the linac subharmonic buncher and the damping ring RF is required. Recently several companies have developed resettable GaAs master/slave D-type flip-flops which are capable of operating at frequencies of 3 GHz and higher. Using these digital devices as frequency dividers, one can phase shift the SLAC CW-RF systems to optimize the timing for filling the storage rings. We have evaluated the performance of integrated circuits from two vendors for our particular application. Using microstrip circuit techniques, we have built and operated in the accelerator several chassis to synchronize a reset signal from the storage rings to the SLAC 2.856 GHz RF and to phase shift divide-by-four and divide-by-sixteen frequency dividers to the nearest 350 psec bucket required for filling. 4 refs., 4 figs., 2 tabs

  6. Development and experience of quality control methods for digital breast tomosynthesis systems.

    Science.gov (United States)

    Strudley, Cecilia J; Young, Kenneth C; Looney, Padraig; Gilbert, Fiona J

    2015-01-01

    To develop tomosynthesis quality control (QC) test methods and use them alongside established two-dimensional (2D) QC tests to measure the performance of digital breast tomosynthesis (DBT) systems used in a comparative trial with 2D mammography. DBT QC protocols and associated analysis were developed, incorporating adaptions of some 2D tests as well as some novel tests. The tomosynthesis tests were: mean glandular dose to the standard breast model; contrast-to-noise ratio in reconstructed focal planes; geometric distortion; artefact spread; threshold contrast detail detection in reconstructed focal planes, alignment of the X-ray beam to the reconstructed image and missed tissue; reproducibility of the tomosynthesis exposure; and homogeneity of the reconstructed focal planes. Summaries of results from the tomosynthesis QC tests are presented together with some 2D results for comparison. The tomosynthesis QC tests and analysis methods developed were successfully applied. The lessons learnt, which are detailed in the Discussion section, may be helpful to others embarking on DBT QC programmes. DBT performance test equipment and analysis methods have been developed. The experience gained has contributed to the subsequent drafting of DBT QC protocols in the UK and Europe.

  7. Demand Controlled Economizer Cycles: A Direct Digital Control Scheme for Heating, Ventilating, and Air Conditioning Systems,

    Science.gov (United States)

    1984-05-01

    Control Ignored any error of 1/10th degree or less. This was done by setting the error term E and the integral sum PREINT to zero If then absolute value of...signs of two errors jeq tdiff if equal, jump clr @preint else zero integal sum tdiff mov @diff,rl fetch absolute value of OAT-RAT ci rl,25 is...includes a heating coil and thermostatic control to maintain the air in this path at an elevated temperature, typically around 80 degrees Farenheit (80 F

  8. Design of monitoring and control system of digital power supply for HIMM based on microcontroller

    International Nuclear Information System (INIS)

    Yu Chunlei; Wu Fengjun; Gao Daqing; Yan Huaihai; Chen Youxin; Guo Yuxin; Huang Yuzhen; Zhang Huajian

    2013-01-01

    The touch screen control system is under development in Heavy Ion Medical Machine (HIMM) project. In this paper, the touch screen control system is studied in detail, which is driven by PIC24 microcontroller. According to the internal protocol of power system , control of power switch , waveform and state display, parameter setting are all implemented in this control system. The communication among microcontroller, FPGA board for power supply and state board is normal and stable during the test. Compared to analog switch control system, the local control system for HIMM is much more convenient and aesthetic, additionally the control accuracy is even higher. (authors)

  9. Adaptive robust pole-placement control of 4-leg voltage-source inverters for standalone photovoltaic systems: Considering digital delays

    International Nuclear Information System (INIS)

    Nasiri, Reza; Radan, Ahmad

    2011-01-01

    Three leg inverters for photovoltaic systems have a lot of disadvantages, especially when the load is unbalanced. These disadvantages are for example, small utilization of the DC link voltage, the dependency of the modulation factor of the load current and the superposition of a DC component with the output AC voltage. A solution for these problems is the 4-leg inverter. Most papers dealing with 4-leg inverters ignore the effect of digital delays in control loop and suggest classic controllers, such as PI controller. However, the transient performance of the system does not become adjustable by applying classic control techniques. Additionally, adaptive control techniques have not yet been discussed for 4-leg inverters. This paper proposes the pole-placement control strategy via state feedback with integral state, which is a modern control technique, to control the system. Consequently, resulted system becomes highly robust. In addition, it suggests a Self-Tuner Regulator to guarantee the adaptive performance of the final system. Moreover, it proposes a novel model, considering digital delays, for 4-leg inverters. Simulation results show that transient performance of the system becomes accurately adjustable and the 4-leg inverter generates balanced voltage, with sinusoidal waveform, in spite of the presence of RL time variant loads.

  10. Apollo guidance, navigation and control: Guidance system operations plan for manned CM earth orbital and lunar missions using Program COLOSSUS 3. Section 3: Digital autopilots (revision 14)

    Science.gov (United States)

    1972-01-01

    Digital autopilots for the manned command module earth orbital and lunar missions using program COLOSSUS 3 are discussed. Subjects presented are: (1) reaction control system digital autopilot, (2) thrust vector control autopilot, (3) entry autopilot and mission control programs, (4) takeover of Saturn steering, and (5) coasting flight attitude maneuver routine.

  11. Guidelines on the defense-in-depth and diversity planning and analysis in digital instrumentation and control systems

    Energy Technology Data Exchange (ETDEWEB)

    Cheon, Se Woo; Park, Jong Kyun; Lee, Ki Young; Kwon, Ki Choon; Lee, Jang Soo; Kim, Jang Yeol

    2000-08-01

    Digital instrumentation and control (I and C) systems are becoming an ever-increasing part in I and C systems of nuclear power plants due to such features such as versatility, flexibility, and reduced sizes. The digital technology introduces a possibility that common-cause or common-mode failures (CCF or CMF) may cause redundant safety systems to fail in such a way that there is loss of safety function. A special form of CMF analysis called 'defense-in-depth and diversity' (D-in-D and D) analysis has been developed to identify possible common-mode failure vulnerabilities and to support a specific licensing action in digital systems. There are two main stages in D-in-D and D activities: both plan and analysis. The purposes of this technical report are (i) to review background of D-in-D and D and some of important issues in digital D-in-D and D, (ii) to provide guidelines for a vendor to prepare planning and/or analysis documents on D-in-D and D, and (iii) to provide guidelines for an evaluator to review applicant's D-in-D and D planning and/or analysis documents, to ensure that the requirements of the D-in-D and D for digital I and C systems are followed. Most of guidelines suggested in this report were based on NUREG/CR-6303 which was published in 1994. The report will be helpful for a vendor to prepare and for an evaluator to review both D-in-D and D planning or analysis documents for digital I and C systems such as the KNGR project.

  12. Guidelines on the defense-in-depth and diversity planning and analysis in digital instrumentation and control systems

    International Nuclear Information System (INIS)

    Cheon, Se Woo; Park, Jong Kyun; Lee, Ki Young; Kwon, Ki Choon; Lee, Jang Soo; Kim, Jang Yeol

    2000-08-01

    Digital instrumentation and control (I and C) systems are becoming an ever-increasing part in I and C systems of nuclear power plants due to such features such as versatility, flexibility, and reduced sizes. The digital technology introduces a possibility that common-cause or common-mode failures (CCF or CMF) may cause redundant safety systems to fail in such a way that there is loss of safety function. A special form of CMF analysis called 'defense-in-depth and diversity' (D-in-D and D) analysis has been developed to identify possible common-mode failure vulnerabilities and to support a specific licensing action in digital systems. There are two main stages in D-in-D and D activities: both plan and analysis. The purposes of this technical report are i) to review background of D-in-D and D and some of important issues in digital D-in-D and D, ii) to provide guidelines for a vendor to prepare planning and/or analysis documents on D-in-D and D, and iii) to provide guidelines for an evaluator to review applicant's D-in-D and D planning and/or analysis documents, to ensure that the requirements of the D-in-D and D for digital I and C systems are followed. Most of guidelines suggested in this report were based on NUREG/CR-6303 which was published in 1994. The report will be helpful for a vendor to prepare and for an evaluator to review both D-in-D and D planning or analysis documents for digital I and C systems such as the KNGR project

  13. Technical and regulatory challenges for digital instrumentation and control and control room systems in nuclear plants

    International Nuclear Information System (INIS)

    Torok, R.; Naser, J.; Harris, T.; Keithline, K.

    2006-01-01

    There are several unsettled technical and licensing issues in the areas of instrumentation and control (I and C), human factors, and updated control room designs that need coordinated, proactive industry attention. Some of these issues are already causing protracted regulatory reviews for existing plants, and left untreated, may cause substantial delays and increased costs for new plant combined construction and operating license approvals. Both industry and the NRC will have roles in resolving the key issues and addressing them in future design efforts and regulatory reviews. Where action is needed, the industry will want to minimize costs and risks by defining industry consensus solutions with corresponding technical bases. NEI has formed a working group to coordinate industry efforts and communications with NRC staff. The working group will also help determine priorities and coordinate both new and existing plant resources. EPRI will provide technical input and guidance for the working group. In order to be able to conduct reviews in a timely fashion, the NRC will likely need to enhance and expand staff resources as existing plants are upgraded and new plant reviews become more active. The industry initiative began with a workshop sponsored by EPRI and NEI on March 28-29, 2006, which led to the creation of the NEI working group. The working group has now identified and prioritized important generic issues, established resolution paths and schedules, and identified the roles of various stakeholders including utility companies, EPRI, NEI, vendors and the NRC. Through the course of this initiative I and C issues for both existing and new plants are being addressed. This paper describes the key I and C related technical and regulatory issues and their implications for new and operating plants, and provides a status report on the efforts to resolve them. (authors)

  14. Advanced digital instrumentation and control system for nuclear power plant protection

    International Nuclear Information System (INIS)

    Sabino, D.

    1997-01-01

    The Diverse Protection System (DPS) is described. The DPS is a state-of-the-art digital protection system developed as a back-up to the primary reactor protection system at the Temelin nuclear power plant, featuring a compact hardware design based on VMEbus technology. This technology allows for ease in adding or modifying the number and type of input modules and processors. The DPS software is written in a high level language suitable for safety critical applications. The software is both modular and configurable allowing for potential future modifications and software reuse

  15. Design of a decoupled AP1000 reactor core control system using digital proportional–integral–derivative (PID) control based on a quasi-diagonal recurrent neural network (QDRNN)

    International Nuclear Information System (INIS)

    Wei, Xinyu; Wang, Pengfei; Zhao, Fuyu

    2016-01-01

    Highlights: • We establish a disperse dynamic model for AP1000 reactor core. • A digital PID control based on QDRNN is used to design a decoupling control system. • The decoupling performance is verified and discussed. • The decoupling control system is simulated under the load following operation. - Abstract: The control system of the AP1000 reactor core uses the mechanical shim (MSHIM) strategy, which includes a power control subsystem and an axial power distribution control subsystem. To address the strong coupling between the two subsystems, an interlock between the two subsystems is used, which can only alleviate but not eliminate the coupling. Therefore, sometimes the axial offset (AO) cannot be controlled tightly, and the flexibility of load-following operation is limited. Thus, the decoupling of the original AP1000 reactor core control system is the focus of this paper. First, a two-node disperse dynamic model is established for the AP1000 reactor core to use PID control. Then, a digital PID control system based on a quasi-diagonal recurrent neural network (QDRNN) is designed to decouple the original system. Finally, the decoupling of the control system is verified by the step signal and load-following condition. The results show that the designed control system can decouple the original system as expected and the AO can be controlled much more tightly. Moreover, the flexibility of the load following is increased.

  16. Design of a decoupled AP1000 reactor core control system using digital proportional–integral–derivative (PID) control based on a quasi-diagonal recurrent neural network (QDRNN)

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Xinyu, E-mail: xyuwei@mail.xjtu.edu.cn; Wang, Pengfei, E-mail: pengfeixiaoli@yahoo.cn; Zhao, Fuyu, E-mail: fuyuzhao_xj@163.com

    2016-08-01

    Highlights: • We establish a disperse dynamic model for AP1000 reactor core. • A digital PID control based on QDRNN is used to design a decoupling control system. • The decoupling performance is verified and discussed. • The decoupling control system is simulated under the load following operation. - Abstract: The control system of the AP1000 reactor core uses the mechanical shim (MSHIM) strategy, which includes a power control subsystem and an axial power distribution control subsystem. To address the strong coupling between the two subsystems, an interlock between the two subsystems is used, which can only alleviate but not eliminate the coupling. Therefore, sometimes the axial offset (AO) cannot be controlled tightly, and the flexibility of load-following operation is limited. Thus, the decoupling of the original AP1000 reactor core control system is the focus of this paper. First, a two-node disperse dynamic model is established for the AP1000 reactor core to use PID control. Then, a digital PID control system based on a quasi-diagonal recurrent neural network (QDRNN) is designed to decouple the original system. Finally, the decoupling of the control system is verified by the step signal and load-following condition. The results show that the designed control system can decouple the original system as expected and the AO can be controlled much more tightly. Moreover, the flexibility of the load following is increased.

  17. Future approaches to digital systems

    International Nuclear Information System (INIS)

    Woodrough, R.E.; Beckmann, E.; Jenkins, D.; Belcher, D.

    1984-01-01

    The introduction of the first digital imaging systems has led to the concept of a totally digital imaging department - the 'filmless department'. This concept and its associated network system for digital departments are briefly considered. A transducer system of scanned projection radiography with solid state detectors used in digital chest imaging is described. The principles of this transducer system are applicable to other forms of digital radiography. (U.K.)

  18. Cavity digital control testing system by Simulink step operation method for TESLA linear accelerator and free electron laser

    Science.gov (United States)

    Czarski, Tomasz; Romaniuk, Ryszard S.; Pozniak, Krzysztof T.; Simrock, Stefan

    2004-07-01

    The cavity control system for the TESLA -- TeV-Energy Superconducting Linear Accelerator project is initially introduced in this paper. The FPGA -- Field Programmable Gate Array technology has been implemented for digital controller stabilizing cavity field gradient. The cavity SIMULINK model has been applied to test the hardware controller. The step operation method has been developed for testing the FPGA device coupled to the SIMULINK model of the analog real plant. The FPGA signal processing has been verified according to the required algorithm of the reference MATLAB controller. Some experimental results have been presented for different cavity operational conditions.

  19. Human Factors Guidance for Control Room and Digital Human-System Interface Design and Modification, Guidelines for Planning, Specification, Design, Licensing, Implementation, Training, Operation and Maintenance

    Energy Technology Data Exchange (ETDEWEB)

    R. Fink, D. Hill, J. O' Hara

    2004-11-30

    Nuclear plant operators face a significant challenge designing and modifying control rooms. This report provides guidance on planning, designing, implementing and operating modernized control rooms and digital human-system interfaces.

  20. Human Factors Guidance for Control Room and Digital Human-System Interface Design and Modification. Guidelines for Planning, Specification, Design, Licensing, Implementation, Training, Operation and Maintenance

    International Nuclear Information System (INIS)

    Fink, R.; Hill, D.; O'Hara, J.

    2004-01-01

    Nuclear plant operators face a significant challenge designing and modifying control rooms. This report provides guidance on planning, designing, implementing and operating modernized control rooms and digital human-system interfaces

  1. Controlling the digital transfer process

    Science.gov (United States)

    Brunner, Felix

    1997-02-01

    The accuracy of today's color management systems fails to satisfy the requirements of the graphic arts market. A first explanation for this is that color calibration charts on which these systems rely, because of print technical reasons, are subject to color deviations and inconsistencies. A second reason is that colorimetry describes the human visual perception of color differences and has no direct relation to the rendering technology itself of a proofing or printing device. The author explains that only firm process control of the many parameters in offset printing by means of a system as for example EUROSTANDARD System Brunner, can lead to accurate and consistent calibration of scanner, display, proof and print. The same principles hold for the quality management of digital presses.

  2. Impact of Advanced Alarm Systems and Information Displays on Human Reliability in the Digital Control Room of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kim, Jong Hyun; Dang, Vinh N

    2011-01-01

    This paper discusses the potential impacts of two advanced features of digital control rooms, alarm systems and information display systems, on the Human Reliability Analysis (HRA) in nuclear power plants. Although the features of digital control rooms have already been implemented in new or upgraded nuclear power plants, HRAs have so far not taken much credit for these features. In this circumstance, this paper aims at examining the potential effects of these features on human performance and discussing how these effects can be addressed with existing HRA methods. A conclusion derivable from past experimental studies is that those features are supportive in the severe conditions such as complex scenarios and knowledge-based works. However, in the less complex scenarios and rule-based work, they may have no difference with or sometimes negative impacts on operator performance. The discussion about the impact on the HRA is provided on the basis on the THERP method

  3. Technology Transfer Programme In Reactor Digital Instrumentation And Control System (REDICS) Project: Knowledge, Experiences And Future Expectations

    International Nuclear Information System (INIS)

    Nurfarhana Ayuni Joha; Mohamad Puad Abu; Izhar Abu Hussin; Ridzuan Abdul Mutalib; Zareen Khan Abdul Jalil Khan; Mohd Khairulezwan Abdul Manan; Mohd Sabri Minhat; Mohd Idris Taib

    2013-01-01

    The PUSPATI TRIGA MARK II research reactor in Malaysia was commissioned in 1982. After 31 years of operation, Nuclear Malaysia is taking an approach for a better research and development in nuclear radiations as well as the technical services that provided. Reactor TRIGA PUSPATI (RTP) is currently upgrading its control console from analogue to digital system. The Reactor Digital Instrumentation and Control System (ReDICS) project is done on cooperation with Korea Atomic Energy Research Institute (KAERI), Korea including the technical part from the design stage until commissioning as well as the Technology Transfer Program (TTP). TTP in this ReDICS project is a part of Human Resource and System Development Program. It was carried out from the design stage until the commissioning of the system. It covers all subjects related to the design on the digital system and the requirements for the operation of RTP. The objective of this paper is to share the knowledge and experiences gained through this ReDICS project. This paper will also discuss the future expectations from this ReDICS project for Nuclear Malaysia and its personnel, as well as to the country. (author)

  4. Ultra-Portable Smartphone Controlled Integrated Digital Microfluidic System in a 3D-Printed Modular Assembly

    OpenAIRE

    Yafia, Mohamed; Ahmadi, Ali; Hoorfar, Mina; Najjaran, Homayoun

    2015-01-01

    Portable sensors and biomedical devices are influenced by the recent advances in microfluidics technologies, compact fabrication techniques, improved detection limits and enhanced analysis capabilities. This paper reports the development of an integrated ultraportable, low-cost, and modular digital microfluidic (DMF) system and its successful integration with a smartphone used as a high-level controller and post processing station. Low power and cost effective electronic circuits are designed...

  5. Paper-Based Digital Microfluidic Chip for Multiple Electrochemical Assay Operated by a Wireless Portable Control System

    DEFF Research Database (Denmark)

    Ruecha, Nipapan; Lee, Jumi; Chae, Heedo

    2017-01-01

    for multiple analysis assays are fabricated by affordable printing techniques. For enhanced sensitivity of the sensor, the working electrode is modified through the electrochemical method, namely by reducing graphene with voltammetry and coating gold nanoparticles by amperometry. Detachable sensor and absorber...... designed portable power supply and wireless control system, the active paper-based chip platform can be utilized as an advanced point-of-care device for multiple assays in digital microfluidics....

  6. The reliability of the software of the digital control system Nuclear Advantage

    International Nuclear Information System (INIS)

    Graae, T.; Engdahl, L.

    1996-01-01

    The ABB nuclear power control system Nuclear Advantage is a truly integrated control system. The integration of process control and safety control aims at achieving a common operator interface in order to simplify and thus improve control room ergonomics. The challenge is to design an integrated control system and at the same time ensure the functional separation between the independent safety subsystems as well as between the safety and the conventional sections. Software reliability is discussed and illustrated by statistical test results. It has proved to be a hundred times better than the reliability of the high-quality hardware. (orig.) [de

  7. An examination of automatic exposure control regimes for two digital radiography systems

    International Nuclear Information System (INIS)

    Marshall, N W

    2009-01-01

    The influence of two methods of an automatic exposure control (AEC) setup using a simple measure of detectability is examined as a function of x-ray beam quality for a computed radiography (CR) system and for an indirect conversion digital radiography (DR) system. The regimes assessed were constant air kerma at the detector and the constant contrast noise ratio (CNR). A low scatter geometry was employed with x-ray spectra varying from 60 kV and 1 mm Cu to 125 kV and 2 mm Cu. The CNR was measured using a 2 mm thick Al square of dimension 1 cm by 1 cm. Detectability was quantified via a nominal contrast for a fixed beam quality of 70 kV and 1 mm added Cu filtration, taken from c-d curves measured using the Leeds TO20 test object, for the four x-ray spectra. In addition, objective image quality parameters including modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE) were also measured for both systems at the four different x-ray spectra. It was found that the constant air kerma strategy did not maintain threshold nominal contrast (simple detectability) constant as the x-ray beam mean energy increased, for either the CR system or the DR system. For the CR detector, the threshold nominal contrast for a 1 mm disc increased by a factor of 4.4 from 3.50% to 15.4% as the tube potential was raised from 60 kV to 125 kV, while for the DR detector, the threshold nominal contrast increased by a factor of 3.4, from 2.27% to 7.67% as the tube potential increased from 60 kV to 120 kV. The constant CNR method was more successful at maintaining constant detectability for the c-d discs. The threshold nominal contrast for the 1 mm disc changed by a factor of 1.2, from 4.80% to 5.70% for the CR system, as the spectrum changed from 60 kV to 125 kV. For the indirect conversion detector, the threshold nominal contrast increased from 2.27% to 5.66% (a factor of 1.4 increase). The constant CNR strategy required an increase in air kerma by

  8. An examination of automatic exposure control regimes for two digital radiography systems

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, N W [Radiation Safety Section, Clinical Physics CAU, Dominion House, 60, Barts Close, St Bartholomew' s Hospital, EC1A 7BE, London (United Kingdom)], E-mail: nicholas.marshall@uz.kuleuven.ac.be

    2009-08-07

    The influence of two methods of an automatic exposure control (AEC) setup using a simple measure of detectability is examined as a function of x-ray beam quality for a computed radiography (CR) system and for an indirect conversion digital radiography (DR) system. The regimes assessed were constant air kerma at the detector and the constant contrast noise ratio (CNR). A low scatter geometry was employed with x-ray spectra varying from 60 kV and 1 mm Cu to 125 kV and 2 mm Cu. The CNR was measured using a 2 mm thick Al square of dimension 1 cm by 1 cm. Detectability was quantified via a nominal contrast for a fixed beam quality of 70 kV and 1 mm added Cu filtration, taken from c-d curves measured using the Leeds TO20 test object, for the four x-ray spectra. In addition, objective image quality parameters including modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE) were also measured for both systems at the four different x-ray spectra. It was found that the constant air kerma strategy did not maintain threshold nominal contrast (simple detectability) constant as the x-ray beam mean energy increased, for either the CR system or the DR system. For the CR detector, the threshold nominal contrast for a 1 mm disc increased by a factor of 4.4 from 3.50% to 15.4% as the tube potential was raised from 60 kV to 125 kV, while for the DR detector, the threshold nominal contrast increased by a factor of 3.4, from 2.27% to 7.67% as the tube potential increased from 60 kV to 120 kV. The constant CNR method was more successful at maintaining constant detectability for the c-d discs. The threshold nominal contrast for the 1 mm disc changed by a factor of 1.2, from 4.80% to 5.70% for the CR system, as the spectrum changed from 60 kV to 125 kV. For the indirect conversion detector, the threshold nominal contrast increased from 2.27% to 5.66% (a factor of 1.4 increase). The constant CNR strategy required an increase in air kerma by

  9. Integrating software reliability concepts into risk and reliability modeling of digital instrumentation and control systems used in nuclear power plants

    International Nuclear Information System (INIS)

    Arndt, S. A.

    2006-01-01

    As software-based digital systems are becoming more and more common in all aspects of industrial process control, including the nuclear power industry, it is vital that the current state of the art in quality, reliability, and safety analysis be advanced to support the quantitative review of these systems. Several research groups throughout the world are working on the development and assessment of software-based digital system reliability methods and their applications in the nuclear power, aerospace, transportation, and defense industries. However, these groups are hampered by the fact that software experts and probabilistic safety assessment experts view reliability engineering very differently. This paper discusses the characteristics of a common vocabulary and modeling framework. (authors)

  10. Software life cycle process and classification guides for KNICS digital instrumentation and control system design

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jang Soo; Son, Han Seung; Kim, Jang Yeol; Kwon, Kee Choon; Lee, Soon Seung; Kim, Doo Hwan [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-04-01

    Documentation should exist that shows that the qualification activities have been successfully accomplished for each life cycle activity group. In particular, the documentation should show that the system safety requirements have been adequately addressed for each life cycle activity group, that no new hazards have been introduced, and that the software requirements, design elements, and code elements that can affect safety have been identified. Because the safety of software can be assured through both the process Verification and Validation (V and V) itself and the V and V of all the intermediate and final products during the software development lifecycle, the development of KNICS Software Safety Framework (KSSF) must be established. As the first activity for establishing KSSF, we have developed this report, Software Life Cycle Process and Classification Guides for KNICS Digital I and C System. This report is organized as follows. Chapter I describes the background, definitions, and references of SLCP. Chapter II describes KNICS safety software categorization. In Chapter III, we define the requirements on software life cycle process for designing digital KNICS. Chapter III.3, that is the main section of the chapter, includes the requirements for software life cycle process planning, the requirements for software life cycle process implementation, and the requirements for software life cycle process design outputs. Finally, we have described the result of a case study on the SLCP for developing the software of ESF-CCS system that is being developed by a private company, BNF. 29 refs., 5 figs., 7 tabs. (Author)

  11. Didactic System for the Experimental Study of Digital PID Control Structures

    OpenAIRE

    Stelian-Emilian OLTEAN; Mircea DULĂU; Adrian-Vasile DUKA

    2016-01-01

    The proportional integral derivative (PID) controller has a known structure used in feedback control of industrial processes. One of the most common applications is the control of the DC motor. The paper presents a didactic system designed for educational purposes used for studying various conventional PID structures and the influence of the PID components in the control process of the DC motor’s speed. The system contains a low cost acquisition board based on PIC 16F628A microcontroller. The...

  12. An alternative method for noise analysis using pixel variance as part of quality control procedures on digital mammography systems

    International Nuclear Information System (INIS)

    Bouwman, R; Broeders, M; Van Engen, R; Young, K; Lazzari, B; Ravaglia, V

    2009-01-01

    According to the European Guidelines for quality assured breast cancer screening and diagnosis, noise analysis is one of the measurements that needs to be performed as part of quality control procedures on digital mammography systems. However, the method recommended in the European Guidelines does not discriminate sufficiently between systems with and without additional noise besides quantum noise. This paper attempts to give an alternative and relatively simple method for noise analysis which can divide noise into electronic noise, structured noise and quantum noise. Quantum noise needs to be the dominant noise source in clinical images for optimal performance of a digital mammography system, and therefore the amount of electronic and structured noise should be minimal. For several digital mammography systems, the noise was separated into components based on the measured pixel value, standard deviation (SD) of the image and the detector entrance dose. The results showed that differences between systems exist. Our findings confirm that the proposed method is able to discriminate systems based on their noise performance and is able to detect possible quality problems. Therefore, we suggest to replace the current method for noise analysis as described in the European Guidelines by the alternative method described in this paper.

  13. The Digital Feedback RF Control System of the RFQ and DTL1 for 100 MeV Proton Linac of PEFP

    CERN Document Server

    Yu In Ha; Cho, Yong-Sub; Han, Yeung-Jin; Kang Heung Sik; Kim, Sung-Chul; Kwon, Hyeok-Jung; Park, In-Soo; Tae Kim, Do; Tae Seol, Kyung

    2005-01-01

    The 100 MeV Proton linear accelerator (Linac) for the PEFP (Proton Engineering Frontier Project) will include 1 RFQ and 1 DTL1 at 350 MHz as well as 7 DTL2 cavities at 700 MHz. The low level RF system with the digital feedback RF control provides the field control to accelerate a 20mA proton beam from 50 keV to 20 MeV with a RFQ and a DTL1 at 350M Hz. The FPGA-based digital feedback RF control system has been built and is used to control cavity field amplitude within ± 1% and relative phase within ± 1°. The fast digital processing is networked to the EPICS-based control system with an embedded processor (Blackfin). In this paper, the detailed description of the digital feedback RF control system will be described with the performance test results.

  14. Risk assessment of safety data link and network communication in digital safety feature control system of nuclear power plant

    International Nuclear Information System (INIS)

    Lee, Sang Hun; Son, Kwang Seop; Jung, Wondea; Kang, Hyun Gook

    2017-01-01

    Highlights: • Safety data communication risk assessment framework and quantitative scheme were proposed. • Fault-tree model of ESFAS unavailability due to safety data communication failure was developed. • Safety data link and network risk were assessed based on various ESF-CCS design specifications. • The effect of fault-tolerant algorithm reliability of safety data network on ESFAS unavailability was assessed. - Abstract: As one of the safety-critical systems in nuclear power plants (NPPs), the Engineered Safety Feature-Component Control System (ESF-CCS) employs safety data link and network communication for the transmission of safety component actuation signals from the group controllers to loop controllers to effectively accommodate various safety-critical field controllers. Since data communication failure risk in the ESF-CCS has yet to be fully quantified, the ESF-CCS employing data communication systems have not been applied in NPPs. This study therefore developed a fault tree model to assess the data link and data network failure-induced unavailability of a system function used to generate an automated control signal for accident mitigation equipment. The current aim is to provide risk information regarding data communication failure in a digital safety feature control system in consideration of interconnection between controllers and the fault-tolerant algorithm implemented in the target system. Based on the developed fault tree model, case studies were performed to quantitatively assess the unavailability of ESF-CCS signal generation due to data link and network failure and its risk effect on safety signal generation failure. This study is expected to provide insight into the risk assessment of safety-critical data communication in a digitalized NPP instrumentation and control system.

  15. Centralized digital control of accelerators

    International Nuclear Information System (INIS)

    Melen, R.E.

    1984-01-01

    Upon careful examination of the architecture of SLAC's computer control systems, it becomes evident that the distribution of the systems' intelligence generally falls into tree-like layers. The first layer typically consists of a central computer complex incorporating one or more relatively large and powerful processors. The more modern systems use state-of-the-art 32-bit processors with several megabytes of RAM and several hundreds of megabytes of disk memory. Further, they support extensive user-friendly operating systems and program development facilities. The second layer typically consists of several smaller processors which are downloaded from the central complex and whose primary task is to provide data acquisition and distribution. The more modern systems are 16-bit processors with several hundred kilobytes of RAM and no disk memory. The third layer typically consists of several tens or hundreds of micro-processors, each dedicated to a single device. The micro-processors for these ''dedicated intelligent controllers'' are small and inexpensive and typically require less than 32 kilobytes of RAM or EPROM memory. Their hardware may be general purpose in nature or may be built into the architecture of the device itself. Figure 5 illustrates several of the relevant features of each of these layers. This paper serves to illustrate that SLAC is commited to the centralized digital control of its accelerators

  16. Control of horizontal plasma position by feedforward-feedback system with digital computer in JIPP T-II tokamak

    International Nuclear Information System (INIS)

    Toi, K.; Sakurai, K.; Itoh, S.; Matsuura, K.; Tanahashi, S.

    1980-01-01

    In the resistive shell tokamak, JIPP T-II, the control of horizontal plasma position is successfully carried out by calculating the equilibrium equation in a thin resistive shell from a large-aspect-ratio approximation every 1.39 msec with a digital computer. The iron core effect also is taken account by a simple form in the equation. The required strength of vertical field is determined by the control-demand composed of a ''feedback'' term with Proportion-Integration-Differentiation correction (PID-controller) and ''feedforward'' one in proportion to plasma current. The experimental results have a satisfactory agreement with the analysis of control system. By this control system, the horizontal displacement has been suppressed within 1 cm throughout a discharge for the plasma of 15 cm-radius with high density and low q(a)-value obtained by the second current rise and strong gas puffing. (author)

  17. Warning: digital systems ahead

    International Nuclear Information System (INIS)

    Albrigo, T.

    1994-01-01

    Digital systems will continue to enhance operation and safety in the nuclear industry. However, they are complex and operators have found it difficult to demonstrate the levels of reliability needed to justify their use. This article describes just some of the varied experiences collected by Arizona Public Service and lessons learned which show clearly why caution must be used whenever and wherever these are introduced. (author)

  18. Distributed digital control system : features and maintenance experience (Paper No. 3.6)

    International Nuclear Information System (INIS)

    Awalkar, A.U.

    1992-01-01

    Distributed process control system is a collection of processing elements which are interconnected both logically and physically with decentralised system. It does wide control of resources for cooperative execution of application programs. Distributed processing is useful in process for the reasons such as increased performance through resource sharing, increased reliability, modularity and expandability and reduced cabling cost. (author). 2 figs

  19. Digital LN2 control system for superconducting linac at PLF, Mumbai

    International Nuclear Information System (INIS)

    Karande, J.N.; Dhumal, P.; Takke, A.N.; Pal, S.; Nanal, V.; Pillay, R.G.

    2013-01-01

    The superconducting LINAC at PLF, Mumbai has a modular structure with eight cryostats divided in two groups. Each cryostat has a LN2 vessel of ∼ 40L capacity, which serves as a thermal shield for helium vessel. A coaxial capacitance type sensor is developed in house to measure the LN2 level. Monostable multi-vibrator based readout electronics is designed to measure the change in capacitance due to LN2 level change. The sensor capacitance with a fixed value resistor decides the 'ON' time of the monostable multi-vibrator. A 16 bit timer of microcontroller 8051 is used to measure the pulse width. The change in pulse width is converted into a LN2 level and displayed on a 4*20 LCD screen. The control unit is also equipped with automatic control of LN2 filling valves triggered by levels. The digital LN2 control can be operated locally or remotely via a serial RS232 communication line.Two control stations are designed and developed to take care of eight cryostats. (author)

  20. A learning flight control system for the F8-DFBW aircraft. [Digital Fly-By-Wire

    Science.gov (United States)

    Montgomery, R. C.; Mekel, R.; Nachmias, S.

    1978-01-01

    This report contains a complete description of a learning control system designed for the F8-DFBW aircraft. The system is parameter-adaptive with the additional feature that it 'learns' the variation of the control system gains needed over the flight envelope. It, thus, generates and modifies its gain schedule when suitable data are available. The report emphasizes the novel learning features of the system: the forms of representation of the flight envelope and the process by which identified parameters are used to modify the gain schedule. It contains data taken during piloted real-time 6 degree-of-freedom simulations that were used to develop and evaluate the system.

  1. Introduction to digital communication systems

    CERN Document Server

    Wesolowski, Krzysztof

    2009-01-01

    Combining theoretical knowledge and practical applications, this advanced-level textbook covers the most important aspects of contemporary digital communication systems. Introduction to Digital Communication Systems focuses on the rules of functioning digital communication system blocks, starting with the performance limits set by the information theory. Drawing on information relating to turbo codes and LDPC codes, the text presents the basic methods of error correction and detection, followed by baseband transmission methods, and single- and multi-carrier digital modulations. The basi

  2. Progress of nuclear safety for symbiosis and sustainability advanced digital instrumentation, control and information systems for nuclear power plants

    CERN Document Server

    Yoshikawa, Hidekazu

    2014-01-01

    This book introduces advanced methods of computational and information systems allowing readers to better understand the state-of-the-art design and implementation technology needed to maintain and enhance the safe operation of nuclear power plants. The subjects dealt with in the book are (i) Full digital instrumentation and control systems and human?machine interface technologies (ii) Risk? monitoring methods for large and? complex? plants (iii) Condition monitors for plant components (iv) Virtual and augmented reality for nuclear power plants and (v) Software reliability verification and val

  3. Didactic System for the Experimental Study of Digital PID Control Structures

    Directory of Open Access Journals (Sweden)

    Stelian-Emilian OLTEAN

    2016-12-01

    Full Text Available The proportional integral derivative (PID controller has a known structure used in feedback control of industrial processes. One of the most common applications is the control of the DC motor. The paper presents a didactic system designed for educational purposes used for studying various conventional PID structures and the influence of the PID components in the control process of the DC motor’s speed. The system contains a low cost acquisition board based on PIC 16F628A microcontroller. The experimental results are shown graphically using a PC application made in Matlab environment.

  4. Functioning strategy study on control systems of large physical installations used with a digital computer

    International Nuclear Information System (INIS)

    Bel'man, L.B.; Lavrikov, S.A.; Lenskij, O.D.

    1975-01-01

    A criterion to evaluate the efficiency of a control system functioning of large physical installations by means of a control computer. The criteria are the object utilization factor and computer load factor. Different strategies of control system functioning are described, and their comparative analysis is made. A choice of such important parameters as sampling time and parameter correction time is made. A single factor to evaluate the system functioning efficiency is introduced and its dependence on the sampling interval value is given. Using diagrams attached, it is easy to find the optimum value of the sampling interval and the corresponding maximum value of the single efficiency factor proposed

  5. RodPilotR - The Innovative and Cost-Effective Digital Control Rod Drive Control System for PWRs

    International Nuclear Information System (INIS)

    Baron, Clemens

    2008-01-01

    With RodPilot, AREVA NP offers an innovative and cost-effective system for controlling control rods in Pressurized Water Reactors. RodPilot controls the three operating coils of the control rod drive mechanism (lift, moveable gripper and stationary gripper coil). The rods are inserted into or withdrawn from the core as required by the Reactor Control System. The system combines modern components, state-of-the-art logic and a proven electronic control rod drive control principle to provide enhanced reliability and lower maintenance costs. (author)

  6. RodPilot{sup R} - The Innovative and Cost-Effective Digital Control Rod Drive Control System for PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Baron, Clemens [AREVA NP GmbH, NLEE-G, Postfach 1199, 91001 Erlangen (Germany)

    2008-07-01

    With RodPilot, AREVA NP offers an innovative and cost-effective system for controlling control rods in Pressurized Water Reactors. RodPilot controls the three operating coils of the control rod drive mechanism (lift, moveable gripper and stationary gripper coil). The rods are inserted into or withdrawn from the core as required by the Reactor Control System. The system combines modern components, state-of-the-art logic and a proven electronic control rod drive control principle to provide enhanced reliability and lower maintenance costs. (author)

  7. Analysis of specific features of digital instrumentation and control systems and possibilities of accounting for them within PSA

    International Nuclear Information System (INIS)

    Hustak, S.

    2002-10-01

    The report is structured as follows: Basic information on the peculiarities of digital technology for the I and C system at an NPP (Digital signal; Digital communication; Communication protocols; Examples of practical tools for creation of I and C digital systems); Peculiarities of the digital I and C technology from the reliability viewpoint (Software as a new component of implementation of a system function; Problems with the assessment or demonstration of reliability of software components of an I and C system); Possibilities of accounting for the specific features of digital I and C technology within PSA (Relevant PSA components; Using PSA as a supporting tool in designing new NPPs; Categorization of NPP I and C system tasks with respect to the defence-in-depth principle). (P.A.)

  8. Digital controls for plant control systems at the Ulchin 5 and 6 NPP: Lessons for the U.S. NPP retrofits?

    International Nuclear Information System (INIS)

    McCreary, T.; Stevens, J.

    2006-01-01

    South Korea, through its nuclear operating arm, Korea Hydro and Nuclear Power, Ltd. (KHNP), has been one of the leading countries in the routine construction and operation of nuclear power plants. While standardizing on certain design approaches in the plant, KHNP continues to stress the need for the most reliable and cutting edge I and C technologies available for safety and non safety related NSSS and BOP functions. Its specifications are among the most challenging in the world with regard to the system performance and reliability requirements that must be met for the systems to be supplied. The Ulchin Units 5 and 6 (1000 MW each) nuclear power plants have been recently commissioned (2004 and 2005 respectively) with advanced programmable digital control systems in the NSSS and BOP (which includes both safety and non-safety applications). The systems supplied met what the authors believe are the most rigorous performance and functional specification criteria in use today. The authors will highlight a number of the specification requirements, the rationale for same and the plant experiences in the resultant supplied systems. As the existing U.S. nuclear fleet is faced with the prospect of upgrading legacy controls with digital controls, there are valuable lessons to be learned in the Ulchin 5 and 6 experiences that can be applied to retrofits and even new U.S. plant designs. Ulchin 5 and 6 is one of the success stories in the application of advanced digital technology to nuclear power plants. The specification focus that guided the selection and project execution for the digital controls supplied for Ulchin was on several key areas: a) a high reliable fault tolerant system, b)functional segmentation to minimize the failure effects on operation, c) validation and verification of the owner's engineer's application design (for regulatory compliance) as well as validation and verification of the system architecture and operation (to assure system performance met

  9. Safety implications of using programmable digital computers in nuclear safety and control systems

    International Nuclear Information System (INIS)

    Adams, D.M.; Rohrdanz, R.R.

    1982-01-01

    This papers describes the activities being conducted at the Idaho National Engineering Laboratory associated with the use of stored-program computers for protection and control systems. This project has recently been initiated and a preliminary report will be available. The use of computers in plant control and protection (and more generally in system important to safety) represents a major departure from the systems which have been used in the past. The design, development, and audit methods used for these systems are significantly different, thus requiring different skills and different perspectives

  10. Digital control for turbogas units; Control digital para unidades turbogas

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Beltran, Carlos Daniel

    1997-02-01

    The present thesis deals with the rehabilitation of the control system for the gas turbines W501 of the Gomez Palacio Combined Cycle Power Station in the state of Durango, Mexico. The first part of the development deals with a re-engineering process of software applied to the digital control system of the gas turbines of the Gomez Palacio Combined Cycle Power Station. This process was developed using concepts of several branches of engineering: a) involved the knowledge of the software engineering, using formal methods for the analysis of the original system and the redesign of the new system; b) The control engineering was used in the analysis of diverse control and automation strategies employed for gas turbines control, with the objective of verifying the type of instructions and existing routines within the software. The final product of this stage is a modulated programmatic system, based on structured design that is functionally a mirror image of the original system. The system obtained conformed by five main modules which are based on a model proposed originally for control by batch: i) Man Machine Interface, ii) Regulatory Control, iii) Protections, iv) Logic sequences and v) Supervision. The second stage of development was the improvement of the speed control of the turbine. When a turbogas unit is controlled, it must be taken into account several operation stages such as the starting, the control in stable state and the shut down. The real behavior of the turbine during the starting, and mainly the great number of backward movements produced, proposed by itself the search of a new controller who more closely maintained the acceleration specifications whereupon the turbine was designed. The development of a new control algorithm began with the analysis of the process, trying to identify which are the critical stages of this one and be able to evaluate in an objective form the advantages of an algorithm upon the other. It was continued with the

  11. A digital, decentralized power station control system with bus-transmission facilitates the problem of backfitting

    International Nuclear Information System (INIS)

    Kaiser, G.E.; Schemmel, R.R.

    1985-01-01

    Current NPP control equipment technology is essentially characterized by the transmission of information in parallel using individual cables, and utilizes hardwired techniques for the processing of information. Progress in the area of semiconductor development characterized by micro-processors and LSI-circuits, has opened up new possibilities for the solution of the control tasks. The new power station control system PROCONTROL P utilizes these possibilities

  12. Preparation of methodology for reliability analysis of selected digital segments of the instrumentation and control systems of NPPs. Pt. 1

    International Nuclear Information System (INIS)

    Hustak, S.; Patrik, M.; Babic, P.

    2000-12-01

    The report is structured as follows: (i) Introduction; (ii) Important notions relating to the safety and dependability of software systems for nuclear power plants (selected notions from IAEA Technical Report No. 397; safety aspects of software application; reliability/dependability aspects of digital systems); (iii) Peculiarities of digital systems and ways to a dependable performance of the required function (failures in the system and principles of defence against them; ensuring resistance of digital systems against failures at various hardware and software levels); (iv) The issue of analytical procedures to assess the safety and reliability of safety-related digital systems (safety and reliability assessment at an early stage of the project; general framework of reliability analysis of complex systems; choice of an appropriate quantitative measure of software reliability); (v) Selected qualitative and quantitative information about the reliability of digital systems; the use of relations between the incidence of various types of faults); and (vi) Conclusions and recommendations. (P.A.)

  13. A general digital computer procedure for synthesizing linear automatic control systems

    International Nuclear Information System (INIS)

    Cummins, J.D.

    1961-10-01

    The fundamental concepts required for synthesizing a linear automatic control system are considered. A generalized procedure for synthesizing automatic control systems is demonstrated. This procedure has been programmed for the Ferranti Mercury and the IBM 7090 computers. Details of the programmes are given. The procedure uses the linearized set of equations which describe the plant to be controlled as the starting point. Subsequent computations determine the transfer functions between any desired variables. The programmes also compute the root and phase loci for any linear (and some non-linear) configurations in the complex plane, the open loop and closed loop frequency responses of a system, the residues of a function of the complex variable 's' and the time response corresponding to these residues. With these general programmes available the design of 'one point' automatic control systems becomes a routine scientific procedure. Also dynamic assessments of plant may be carried out. Certain classes of multipoint automatic control problems may also be solved with these procedures. Autonomous systems, invariant systems and orthogonal systems may also be studied. (author)

  14. Mathematic Model of Digital Control System with PID Regulator and Regular Step of Quantization with Information Transfer via the Channel of Plural Access

    Science.gov (United States)

    Abramov, G. V.; Emeljanov, A. E.; Ivashin, A. L.

    Theoretical bases for modeling a digital control system with information transfer via the channel of plural access and a regular quantization cycle are submitted. The theory of dynamic systems with random changes of the structure including elements of the Markov random processes theory is used for a mathematical description of a network control system. The characteristics of similar control systems are received. Experimental research of the given control systems is carried out.

  15. Digital Controller For Acoustic Levitation

    Science.gov (United States)

    Tarver, D. Kent

    1989-01-01

    Acoustic driver digitally controls sound fields along three axes. Allows computerized acoustic levitation and manipulation of small objects for such purposes as containerless processing and nuclear-fusion power experiments. Also used for controlling motion of vibration-testing tables in three dimensions.

  16. Development and testing of a digital RF control system and development of a modular data acquisition system for the energy stabilisation of the S-DALINAC

    International Nuclear Information System (INIS)

    Araz, Asim

    2009-01-01

    The subject of this thesis was to construct and test a digital radio-frequency control system for the superconducting Darmstadt electron accelerator S-DALINAC. The controller consists of two components, a low-frequency and a high-frequency module. The high-frequency module developed within this framework is constructed from modern integrated circuits that offer, besides enhanced high-frequency properties, a built-in temperature stabilization. Currently, three superconducting cavities are controlled by the new modules via level converters, thus proving the suitability, and reliability in operation. A new low-frequency module was also commissioned during the course of the present work. It is based, in contrast to the existing control loops, not on analogue but on digital signal processing provided by fast Field Programmable Gate Arrays (FPGA). The fast signal processing capabilities of the new low-frequency unit enabled the implementation of a new, compared to the existing circuit, more advanced control algorithm for the digital control. Within this algorithm integral controllers were added to the proportional controllers in the amplitude as well as in the phase control loops. The digital control can now correct smallest residual errors that could not be compensated by the existing proportional controllers. Additionally, the phase control range was increased to ±180 . by the implementation of a vector rotation. Spurious fix points of the control loop were prevented by a modified amplitude modulation. With these two components, namely, the high- and low-frequency module, the first digital radio-frequency control loop for the S-DALINAC was realized and successfully tested, operating on a superconducting cavity. Under typical operation conditions, an amplitude stability of 2.5.10 -4 and a phase stability of 0.28. were demonstrated. Compared to the current control loops this implies an improved amplitude stability by a factor of 8, while the phase stability remains

  17. Evaluation of digital fault-tolerant architectures for nuclear power plant control systems

    International Nuclear Information System (INIS)

    Battle, R.E.

    1990-01-01

    Four fault tolerant architectures were evaluated for their potential reliability in service as control systems of nuclear power plants. The reliability analyses showed that human- and software-related common cause failures and single points of failure in the output modules are dominant contributors to system unreliability. The four architectures are triple-modular-redundant (TMR), both synchronous and asynchronous, and also dual synchronous and asynchronous. The evaluation includes a review of design features, an analysis of the importance of coverage, and reliability analyses of fault tolerant systems. An advantage of fault-tolerant controllers over those not fault tolerant, is that fault-tolerant controllers continue to function after the occurrence of most single hardware faults. However, most fault-tolerant controllers have single hardware components that will cause system failure, almost all controllers have single points of failure in software, and all are subject to common cause failures. Reliability analyses based on data from several industries that have fault-tolerant controllers were used to estimate the mean-time-between-failures of fault-tolerant controllers and to predict those failures modes that may be important in nuclear power plants. 7 refs., 4 tabs

  18. New drive converter and digital control for the pulsed power supply system of ASDEX Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Käsemann, Claus-Peter, E-mail: c.p.kaesemann@ipp.mpg.de [Max Planck Institute for Plasma Physics, Boltzmannstraße 2, 85748 Garching (Germany); Jacob, Christian; Nguyen, Hong Ha; Stobbe, Ferdinand; Mayer, Alois [Max Planck Institute for Plasma Physics, Boltzmannstraße 2, 85748 Garching (Germany); Sachs, Edgar; Klein, Reiner [Siemens AG, Industrial Automation Systems, Gleiwitzer Straße 555, 90475 Nürnberg (Germany)

    2015-10-15

    Highlights: • IGBT converter system with integrated control. • Proven technology reduces time and budget. • Flexibility to be integrated into a 35 years old installation. • Stable control algorithms for static and dynamic speed control. • Possibilities for active and reactive power management. - Abstract: Safety and reliability are major issues for the ASDEX Upgrade (AUG) pulsed power supply systems. To avoid long downtimes during an experimental campaign, fault-prone components have to be identified and treated early. This becomes even more important due to the AUG participation in the EUROfusion Medium Sized Tokamak (MST) program. Operating equipment which is up to 40 years old adds additional complications. This contribution describes one such example where a 35 year old flywheel generator at AUG was identified as fault-prone and pre-emptively upgraded with a new drive converter with integrated control. Most challenging was to adapt a modern converter, originally designed for wind turbines, toward a drive system for a flywheel-motor-generator system. To identify the layout of the controller and the control parameters, accurate modeling and comprehensive simulations were performed. This effort paid off during commissioning and measuring results verified the calculated design values. Finally, the system shows good performance during AUG plasma experiments.

  19. Functional utilization of control and digital protection systems in distribution substations; Aproveitamento funcional de sistemas de controle e protecao digitais em subestacoes de distribuicao

    Energy Technology Data Exchange (ETDEWEB)

    Brittes, Jose Luiz Pereira

    1996-07-01

    The application of Digital Protection and Control Systems (DPCS) in Utilities substations is a fundamental part for their Information System. Technological progress in Telematics provides nowadays, the implementation of open digital systems. But it is the wide exploitation of its potentiality that will be one of the survival factor in the competitive and multi-affair environment dictated by the new worldwide economical order. This exploitation is carried out in three levels inside the substation: at bay level, with inherent technological benefits, such as more efficient and reliable protection, data acquisition and registration, and smart control; at central level (substation), by the implantation of automatics with enormous operational and management profits; and a remote level, to whom DPCS's transpire like a very sophisticated large frame remote terminal units. (author)

  20. Functional utilization of control and digital protection systems in distribution substations; Aproveitamento funcional de sistemas de controle e protecao digitais em subestacoes de distribuicao

    Energy Technology Data Exchange (ETDEWEB)

    Brittes, Jose Luiz Pereira

    1996-07-01

    The application of Digital Protection and Control Systems (DPCS) in Utilities substations is a fundamental part for their Information System. Technological progress in Telematics provides nowadays, the implementation of open digital systems. But it is the wide exploitation of its potentiality that will be one of the survival factor in the competitive and multi-affair environment dictated by the new worldwide economical order. This exploitation is carried out in three levels inside the substation: at bay level, with inherent technological benefits, such as more efficient and reliable protection, data acquisition and registration, and smart control; at central level (substation), by the implantation of automatics with enormous operational and management profits; and a remote level, to whom DPCS's transpire like a very sophisticated large frame remote terminal units. (author)

  1. Actuator digital interface unit (AIU). [control units for space shuttle data system

    Science.gov (United States)

    1973-01-01

    Alternate versions of the actuator interface unit are presented. One alternate is a dual-failure immune configuration which feeds a look-and-switch dual-failure immune hydraulic system. The other alternate is a single-failure immune configuration which feeds a majority voting hydraulic system. Both systems communicate with the data bus through data terminals dedicated to each user subsystem. Both operational control data and configuration control information are processed in and out of the subsystem via the data terminal which yields the actuator interface subsystem, self-managing within its failure immunity capability.

  2. Dynamic Systems and Control Engineering

    International Nuclear Information System (INIS)

    Kim, Jong Seok

    1994-02-01

    This book deals with introduction of dynamic system and control engineering, frequency domain modeling of dynamic system, temporal modeling of dynamic system, typical dynamic system and automatic control device, performance and stability of control system, root locus analysis, analysis of frequency domain dynamic system, design of frequency domain dynamic system, design and analysis of space, space of control system and digital control system such as control system design of direct digital and digitalization of consecutive control system.

  3. Dynamic Systems and Control Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Seok

    1994-02-15

    This book deals with introduction of dynamic system and control engineering, frequency domain modeling of dynamic system, temporal modeling of dynamic system, typical dynamic system and automatic control device, performance and stability of control system, root locus analysis, analysis of frequency domain dynamic system, design of frequency domain dynamic system, design and analysis of space, space of control system and digital control system such as control system design of direct digital and digitalization of consecutive control system.

  4. Model-based analysis of digital radio frequency control systems for a heavy-ion synchrotron

    International Nuclear Information System (INIS)

    Spies, Christopher

    2013-12-01

    In this thesis, we investigate the behavior of different radio frequency control systems in a heavy-ion synchrotron, which act on the electrical fields used to accelerate charged particles, along with the longitudinal dynamics of the particles in the beam. Due to the large physical dimensions of the system, the required precision can only be achieved by a distributed control system. Since the plant is highly nonlinear and the overall system is very complex, a purely analytical treatment is not possible without introducing unacceptable simplifications. Instead, we use numerical simulation to investigate the system behavior. This thesis arises from a cooperation between the Institute of Microelectronic Systems at Technische Universitaet Darmstadt and the GSI Helmholtz Center for Heavy-Ion Research. A new heavy-ion synchrotron, the SIS100, is currently being built at GSI; its completion is scheduled for 2016. The starting point for the present thesis was the question whether a control concept previously devised at GSI is feasible - not only in the ideal case, but in the presence of parameter deviations, noise, and other disturbances - and how it can be optimized. In this thesis, we present a system model of a heavy-ion synchrotron. This model comprises the beam dynamics, the relevant components of the accelerator, and the relevant controllers as well as the communication between those controllers. We discuss the simulation techniques as well as several simplifications we applied in order to be able to simulate the model in an acceptable amount of time and show that these simplifications are justified. Using the model, we conducted several case studies in order to demonstrate the practical feasibility of the control concept, analyze the system's sensitivity towards disturbances and explore opportunities for future extensions. We derive specific suggestions for improvements from our results. Finally, we demonstrate that the model represents the physical reality

  5. Optimization and test of a digital radio-frequency control system and developments for the EPICS-based accelerator control system at the S-DALINAC

    International Nuclear Information System (INIS)

    Burandt, Christoph Warwick

    2017-01-01

    The first part of this thesis covers multiple extensions of the digital low-level radio-frequency control system of the electron accelerator S-DALINAC. This comprises bringing into regular operation the piezoelectrically driven fine tuners of the superconducting cavities. For this a power supply series has been developed, which is compatible with the existing electronics and can power the piezo elements. Furthermore the flexibility of the radio-frequency control system has been demonstrated on superconducting quarter-wave-resonators of the ion accelerator ALPI. These 160 MHz cavities are quite different to the S-DALINAC's acceleration structures but could be operated successfully with low residual errors in phase and amplitude nevertheless. The second part describes the migration of the accelerator control system to an EPICS-based system. A multitude of devices with a diversity of interfaces and protocols have been integrated and higher-level functionality has been unified. Within the framework of the construction of the third recirculation beam-line, the beam-path-length adjustment mechanism was motorized.

  6. Evaluation of digital fault-tolerant architectures for nuclear power plant control systems

    International Nuclear Information System (INIS)

    Battle, R.E.

    1990-01-01

    This paper reports on four fault-tolerant architectures that were evaluated for their potential reliability in service as control systems of nuclear power plants. The reliability analyses showed that human- and software-related common cause failures and single points of failure in the output modules are dominant contributors to system unreliability. The four architectures are triple-modular-redundant, both synchronous and asynchronous, and also dual synchronous and asynchronous. The evaluation includes a review of design features, an analysis of the importance of coverage, and reliability analyses of fault-tolerant systems. Reliability analyses based on data from several industries that have fault-tolerant controllers were used to estimate the mean-time-between-failures of fault-tolerant controllers and to predict those failure modes that may be important in nuclear power plants

  7. Digital test objects (D.T.O.) for treatment planning systems quality control in external beam radiotherapy

    International Nuclear Information System (INIS)

    Denis, E.

    2008-04-01

    This work presents the conception and implementation of new automatic and quantitative quality assessment methods for geometric treatment planning in external radiotherapy. Treatment planning Systems (T.P.S.) quality control is mandatory in France and in the world because of encountered risks but the physical tools recommended to lead this quality control are not adapted to the situation. We present a new methodology for control quality based on the definition of Digital Test Objects (D.T.O.) that are directly introduced in the T.P.S. without acquisition device. These D.T.O. are consistently defined in a continuous and discrete modes. The T.P.S. responses to input D.T.O. are compared to theoretical results thanks to figures of merit specifically designed for each elementary control. The tests we carried out during this study allow to validate our solutions for the quality assessment of the auto-contouring, auto-margining, isocenter computation, collimator conformation and digitally reconstructed radiograph generation tools, as well as our solutions for marker positioning, collimator and displayed bean rotation, incidence, divergence and dimensions. Quality assessment solutions we propose are then fast and effective (no acquisition by the device, reduced manipulations), and more precise thanks to the continuous-discrete equivalence realized at the beginning of the modelling

  8. The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

    International Nuclear Information System (INIS)

    O'Hara, J.M.; Gunther, W.; Martinez-Guridi, G.

    2010-01-01

    New and advanced reactors will use integrated digital instrumentation and control (I and C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I and C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I and C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I and C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I and C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it appear that a process disturbance has occurred. We used the information obtained as the technical basis upon which to develop HFE review guidance. The guidance addresses the treatment of degraded I and C conditions as part of the design process and the HSI features and functions that support operators to monitor I and C performance and manage I and C degradations when they occur. In addition, we identified topics for future research.

  9. The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, J.M.; W. Gunther, G. Martinez-Guridi

    2010-02-26

    New and advanced reactors will use integrated digital instrumentation and control (I&C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I&C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I&C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I&C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I&C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it appear that a process disturbance has occurred. We used the information obtained as the technical basis upon which to develop HFE review guidance. The guidance addresses the treatment of degraded I&C conditions as part of the design process and the HSI features and functions that support operators to monitor I&C performance and manage I&C degradations when they occur. In addition, we identified topics for future research.

  10. Linear algebra as an alternative approach to the synthesis of digital devices of automation and control systems

    Directory of Open Access Journals (Sweden)

    Nikolay Chernov

    2018-01-01

    Full Text Available The article considers linear algebra as an alternative mathematical tool of logic synthesis of digital structures to Boolean algebra and synthesis methods of digital electronic component base (ECB on its ground. The methods of solving the applied problems of logic synthesis are shown, including the expansion of an arbitrary logic function by means of monotonic functions. The proposed mathematical apparatus actually provides the creation of digital structures on the principles of analog circuitry. It can find application in the design of multivalued digital ECB, specialized system-on-chip and analog-digital sensors with current output. The examples of synthesis of the combinational and sequential two-valued and multivalued digital devices are given. In conclusion, the advantages of linear algebra in comparison with Boolean algebra are formulated.

  11. Reducing methods of patients exposed dose using auto exposure control system in digital radiography

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seong Gyu [Dept. of Diagnostic Radiology, Dong A University Medical Center, Busan (Korea, Republic of)

    2013-06-15

    This study was carried out to reduce patient dose through focus-detector distance, kilovoltage, and a combination of copper filters. In the C, L-spine lateral, Skull AP views were obtained by making changes of 60-100 kV in tube voltage and of 100-200 cm in focus-detector distance and by adding a copper filter when using an auto exposure control device in the digital radiography equipment. The incident dose showed 90 kV, 0.3 mmCu in C-spine lateral with 0.06 mGy under the condition of 200 cm; 100 kV, 0.3 mmCu with 0.40 mGy under the condition of 200 cm and 90 kV 0.3 mmCu in Skull AP with the lowest value of 0.24 mGy under the condition of 140 cm. It was observed that entrance surface dose decreased the most when was increased by 150 cm, 70 kV (C-spine lateral), 81 kV (L-spine lateral). It was also found out that as the between the focus-detector increased in the expansion of the video decreased but the difference was not significant when the distance was 180 cm or more. Skull AP showed the most reduction in the entrance surface dose when the tube voltage was changed by 80 kV, 0.1 mmCu, and 120 cm. Therefore, when using the automatic exposure control device, it is recommended to use the highest tube voltage if possible and to increase focus-detector distance at least by 150-200 cm in wall and 120-140 cm in table in consideration of the radiotechnologist's physical conditions, and to combine 0.1-0.3 mmCu and higher filters. It is thus expected to reduce patient dose by avoiding distortion of images and reducing the entrance surface dose.

  12. Development of digital low level rf system

    International Nuclear Information System (INIS)

    Michizono, Shinichiro; Anami, Shozo; Katagiri, Hiroaki; Fang, Zhigao; Matsumoto, Toshihiro; Miura, Takako; Yano, Yoshiharu; Yamaguchi, Seiya; Kobayashi, Tetsuya

    2008-01-01

    One of the biggest advantages of the digital low level rf (LLRF) system is its flexibility. Owing to the recent rapid progress in digital devices (such as ADCs and DACs) and telecommunication devices (mixers and IQ modulators), digital LLRF system becomes popular in these 10 years. The J-PARC linac LLRF system adopted cPCI crates and FPGA based digital feedback system. Since the LLRF control of the normal conducting cavities are more difficult than super conducting cavities due to its lower Q values, fast processing using the FPGA was the essential to the feedback control. After the successful operation of J-PARC linac LLRF system, we developed the STF (ILC test facility in KEK) LLRF system. Since the klystron drives eight cavities in STF phase 1, we modified the FPGA board. Basic configuration and the performances of these systems are summarized. The future R and D projects (ILC and ERL) is also described from the viewpoints of LLRF. (author)

  13. Design and modernization of the control room with of the new digital I and C systems; El diseno y modernizacion de las salas de control con los nuevos sistemas de I and C digital

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, L. A.; Ortega, F.; Rejas, L.

    2011-07-01

    The use of the new digital I and c systems in the design of the new nuclear power plants, as well as the modernization of the existing ones, implies relevant changes in the control room design. New I and C systems provide new features that affect the control room operating concept, therefore a detailed analysis is required to take into consideration all the operating and human factor aspects. based on Tecnatom's experience, this article presents the methodological approach used as well as the most relevant aspects of this kind of project. (Author)

  14. Digital control for nuclear reactors - lessons learned

    International Nuclear Information System (INIS)

    Bernard, J.A.; Aviles, B.N.; Lanning, D.D.

    1992-01-01

    Lessons learned during the course of the now decade-old MIT program on the digital control of nuclear reactors are enumerated. Relative to controller structure, these include the importance of a separate safety system, the need for signal validation, the role of supervisory algorithms, the significance of command validation, and the relevance of automated reasoning. Relative to controller implementation, these include the value of nodal methods to the creation of real-time reactor physics and thermal hydraulic models, the advantages to be gained from the use of real-time system models, and the importance of a multi-tiered structure to the simultaneous achievement of supervisory, global, and local control. Block diagrams are presented of proposed controllers and selected experimental and simulation-study results are shown. In addition, a history is given of the MIT program on reactor digital control

  15. A digital joint controller for manipulators

    International Nuclear Information System (INIS)

    Holt, E.J.; Palmer, D.E.B.

    1993-01-01

    Nuclear Electric's hydraulic heavy duty manipulators are used at a number of Magnox Power Stations for a wide variety of tasks. In recent years there has been a trend towards the use of manipulators for tasks requiring increasing precision of tip positioning. In order to meet this requirement, a digital controller has been designed to replace the analogue controller board used in almost all manipulator control systems. The new controller allows the programming of a wide range of closed loop control algorithms. Position and drive signal data may be passed to and from the controller by digital means, allowing direct connection to a graphical display system and/or a computer executing a guidance algorithm. The hardware and software design are outlined and performance in the laboratory and the field is reported. (author)

  16. Superconductor Digital-RF Receiver Systems

    Science.gov (United States)

    Mukhanov, Oleg A.; Kirichenko, Dmitri; Vernik, Igor V.; Filippov, Timur V.; Kirichenko, Alexander; Webber, Robert; Dotsenko, Vladimir; Talalaevskii, Andrei; Tang, Jia Cao; Sahu, Anubhav; Shevchenko, Pavel; Miller, Robert; Kaplan, Steven B.; Sarwana, Saad; Gupta, Deepnarayan

    Digital superconductor electronics has been experiencing rapid maturation with the emergence of smaller-scale, lower-cost communications applications which became the major technology drivers. These applications are primarily in the area of wireless communications, radar, and surveillance as well as in imaging and sensor systems. In these areas, the fundamental advantages of superconductivity translate into system benefits through novel Digital-RF architectures with direct digitization of wide band, high frequency radio frequency (RF) signals. At the same time the availability of relatively small 4K cryocoolers has lowered the foremost market barrier for cryogenically-cooled digital electronic systems. Recently, we have achieved a major breakthrough in the development, demonstration, and successful delivery of the cryocooled superconductor digital-RF receivers directly digitizing signals in a broad range from kilohertz to gigahertz. These essentially hybrid-technology systems combine a variety of superconductor and semiconductor technologies packaged with two-stage commercial cryocoolers: cryogenic Nb mixed-signal and digital circuits based on Rapid Single Flux Quantum (RSFQ) technology, room-temperature amplifiers, FPGA processing and control circuitry. The demonstrated cryocooled digital-RF systems are the world's first and fastest directly digitizing receivers operating with live satellite signals in X-band and performing signal acquisition in HF to L-band at ˜30GHz clock frequencies.

  17. Application of digital control in Japanese PWR Plants

    International Nuclear Information System (INIS)

    Taguchi, S.; Kondo, Y.; Teranishi, S.; Matsumiya, M.; Takashima, M.; Nagai, T.

    1986-01-01

    More reliable and flexible control system to improve the plant availability and operability is constantly demanded. In order to answer the demands, digital control systems are being applied to Japanese PWR plants. Microprocessor-based digital control systems are widely used in other industries and show good performance. The digital control system has been already applied to the chemical and volume control system and the radioactive waste disposal system in the operating plants. These systems have been working as expected and demonstrating good performances. The digital control system for the reactor control system, which is the main control system of the PWR plants, is being developed. The design of the system has been already finished and the verification/validation process is now in progress

  18. Digital integrated protection system

    International Nuclear Information System (INIS)

    Savornin, M.; Furet, M.

    1978-01-01

    As a result of technological progress it is now possible to achieve more elaborate protection functions able to follow more closely the phenomena to be supervised. For this reason the CEA, Framatome and Merlin/Gerin/CERCI have undertaken in commonn to develop a Digital Integrated Protection System (D.I.P.S.). This system is designed with the following aims: to improve the safety of the station, . to improve its availability, . to facilitate installation, . to facilitate tests and maintenance. The main characteristics adopted are: . possibilities of obtaining more elaborate monitoring and protection algorithm treatments, . order 4 redundancy of transducers, associated instruments and signal processing, . possibility of inhibiting part of the protection system, . standardisation of equipment, physical and electrical separation of redundant units, . use of multiplexed connections, . automation of tests. Four flow charts are presented: - DIPS with four APUP (Acquisition and Processing Unit for Protection) - APUP - LSU (Logic Safeguard Unit), number LSU corresponding to number fluidic safeguard circuits, - structure of a function unit, - main functions of the APUP [fr

  19. Aircraft digital flight control technical review

    Science.gov (United States)

    Davenport, Otha B.; Leggett, David B.

    1993-01-01

    The Aircraft Digital Flight Control Technical Review was initiated by two pilot induced oscillation (PIO) incidents in the spring and summer of 1992. Maj. Gen. Franklin (PEO) wondered why the Air Force development process for digital flight control systems was not preventing PIO problems. Consequently, a technical review team was formed to examine the development process and determine why PIO problems continued to occur. The team was also to identify the 'best practices' used in the various programs. The charter of the team was to focus on the PIO problem, assess the current development process, and document the 'best practices.' The team reviewed all major USAF aircraft programs with digital flight controls, specifically, the F-15E, F-16C/D, F-22, F-111, C-17, and B-2. The team interviewed contractor, System Program Office (SPO), and Combined Test Force (CTF) personnel on these programs. The team also went to NAS Patuxent River to interview USN personnel about the F/A-18 program. The team also reviewed experimental USAF and NASA systems with digital flight control systems: X-29, X-31, F-15 STOL and Maneuver Technology Demonstrator (SMTD), and the Variable In-Flight Stability Test Aircraft (VISTA). The team also discussed the problem with other experts in the field including Ralph Smith and personnel from Calspan. The major conclusions and recommendations from the review are presented.

  20. Control of horizontal plasma position by feedforward-feedback system with digital computer in the JIPP T-II tokamak

    International Nuclear Information System (INIS)

    Toi, Kazuo; Sakurai, Keiichi; Itoh, Satoshi; Matsuura, Kiyokata; Tanashi, Shugo

    1980-01-01

    In the resistive shell tokamak, JIPP T-II, the control of horizontal plasma position is successfully carried out by calculating the equilibrium equation of a large-aspect-ratio tokamak plasma surrounded by a thin resistive shell of a skin time of 5.2 ms, every 1.39 ms with a digital computer. The iron core effect is also taken into account by a simple form in the equation. The required strenght of vertical field is determined by the control demand composed of two groups; one is a ''feedback'' term expressed by the deviation of plasma position from the desired one and proportion-integration-differentiation correction (PID-controller), and the other is a ''feedforward'' term which is in proportion to the plasma current. The experimental results in a quasi-constant phase of plasma current are in good agreement with the stability analysis of the control system by using the so-called Bode-diagram which is calculated on the assumption that the plasma current is independent of time. By this control system, the horizontal plasma displacement has been suppressed within 1 cm of the initiation of discharge to the termination in the high-density and low-q(a) plasma of 15 cm radius which is obtained by both strong gas puffing and second current rise. (author)

  1. Control of horizontal plasma position by feedforward-feedback system with digital computer in the JIPP T-II tokamak

    International Nuclear Information System (INIS)

    Toi, K.; Itoh, S.; Sakurai, K.; Matsuura, K.; Tanahashi, S.

    1980-02-01

    In the resistive shell tokamak, JIPP T-II, the control of horizontal plasma position is successfully carried out by calculating the equilibrium equation of a large-aspect-ratio tokamak plasma surrounded by a thin resistive shell of a skin time of 5.2 msec, every 1.39 msec with a digital computer. The iron core effect is also taken into account by a simple form in the equation. The required strength of vertical field is determined by the control demand composed of two groups; one is a ''feedback'' term expressed by the deviation of plasma position from the desired one and proportion-integration-differentiation correction (PID-controller), and the other is a ''feedforward'' term which is in proportion to the plasma current. The experimental results have a good agreement with the stability analysis of the control system by using the so-called Bode-diagram. By this control system, the horizontal displacement has been suppressed within 1 cm from the initiation of discharge to the termination in the high-density and low-q(a) plasma of 15 cm-radius which is obtained by both strong gas puffing and second current rise. (author)

  2. Technical support for digital systems technology development. Task order 1: ISP contention analysis and control

    Science.gov (United States)

    Stehle, Roy H.; Ogier, Richard G.

    1993-01-01

    Alternatives for realizing a packet-based network switch for use on a frequency division multiple access/time division multiplexed (FDMA/TDM) geostationary communication satellite were investigated. Each of the eight downlink beams supports eight directed dwells. The design needed to accommodate multicast packets with very low probability of loss due to contention. Three switch architectures were designed and analyzed. An output-queued, shared bus system yielded a functionally simple system, utilizing a first-in, first-out (FIFO) memory per downlink dwell, but at the expense of a large total memory requirement. A shared memory architecture offered the most efficiency in memory requirements, requiring about half the memory of the shared bus design. The processing requirement for the shared-memory system adds system complexity that may offset the benefits of the smaller memory. An alternative design using a shared memory buffer per downlink beam decreases circuit complexity through a distributed design, and requires at most 1000 packets of memory more than the completely shared memory design. Modifications to the basic packet switch designs were proposed to accommodate circuit-switched traffic, which must be served on a periodic basis with minimal delay. Methods for dynamically controlling the downlink dwell lengths were developed and analyzed. These methods adapt quickly to changing traffic demands, and do not add significant complexity or cost to the satellite and ground station designs. Methods for reducing the memory requirement by not requiring the satellite to store full packets were also proposed and analyzed. In addition, optimal packet and dwell lengths were computed as functions of memory size for the three switch architectures.

  3. Impact of digital information and control system platform selection on nuclear power generating plant operating costs

    International Nuclear Information System (INIS)

    Bogard, T.; Radomski, S.; Sterdis, B.; Marta, H.; Bond, V.; Richardson, J.; Ramon, G.; Edvinsson, H.

    1998-01-01

    Information is presented on the benefits of a well-planned information and control systems (I and CS) replacement approach for aging nuclear power generating plants' I and CS. Replacement of an aging I and CS is accompanied by increases in plant profitability. Implementing a structured I and CS replacement with current technology allows improved plant electrical production in parallel with reduced I and CS operations and maintenance cost. Qualitative, quantitative, and enterprise management methods for cost benefit justification are shown to justify a comprehensive approach to I and CS replacement. In addition to the advantages of standard I and CS technologies, examples of new I and CS technologies are shown to add substantial cost benefit justification for I and CS replacements. Focus is upon I and CS replacements at nuclear power plants, however the information is applicable to other types of power generating facilities. (author)

  4. Research on the evaluation model of the software reliability in nuclear safety class digital instrumentation and control system

    International Nuclear Information System (INIS)

    Liu Ying; Yang Ming; Li Fengjun; Ma Zhanguo; Zeng Hai

    2014-01-01

    In order to analyze the software reliability (SR) in nuclear safety class digital instrumentation and control system (D-I and C), firstly, the international software design standards were analyzed, the standards' framework was built, and we found that the D-I and C software standards should follow the NUREG-0800 BTP7-14, according to the NRC NUREG-0800 review of requirements. Secondly, the quantitative evaluation model of SR using Bayesian Belief Network and thirteen sub-model frameworks were established. Thirdly, each sub-models and the weight of corresponding indexes in the evaluation model were analyzed. Finally, the safety case was introduced. The models lay a foundation for review and quantitative evaluation on the SR in nuclear safety class D-I and C. (authors)

  5. Protocol converter for serial communication between digital rectifier controllers and a power plant SCADA system

    Directory of Open Access Journals (Sweden)

    Vukić Vladimir Đ.

    2016-01-01

    Full Text Available The paper describes the protocol converter INT-485-MBRTU, developed for serial communication between the thyristor rectifier (based on the proprietary protocol "INT-CPD-05", according to standard RS-485 and the SCADA system (based on protocol "Modbus RTU", of the same standard in the thermal power plant "Nikola Tesla B1". Elementary data on industrial communication protocols and communication gateways were provided. The basic technical characteristics of the "Omron" programmable logic controller CJ series were described, as well as the developed device INT-485-MBRTU. Protocol converters with two versions of communication software were tested, differing only in one control word, intended for a forced successive change of communication sequences, in opposite to automatic sequence relieve. The device iNT-485-MBRTU, with the program for forced successive change of communication sequences, demonstrated the reliability of data transfer of 100 %, in a sample of approximately 480 messages. For nearly the same sample, the same protocol converter, with a version of the program without any type of message identifiers, transferred less than 60 % of the foreseen data. During multiple sixty-hour tests, the reliability of data transfer of at least 99.9979% was recorded, in 100% of the analysed cases, and for a sample of nearly 96,000 pairs of the send and receive messages. We analysed the results and estimated the additional possibilities for application of the INT-485-MBRTU protocol converter.

  6. Design and Implement a Digital H{sub {infinity}}Robust Controller for a MW-Class PMSG-Based Grid-Interactive Wind Energy Conversion System

    Energy Technology Data Exchange (ETDEWEB)

    Howlander, Abdul Motin [Faculty of Engineering, Univ. of the Ryukyus, Okinawa (Japan); Urasaki, Naomitsu [Faculty of Engineering, Univ. of the Ryukyus, Okinawa (Japan); Yona, Atsushi [Faculty of Engineering, Univ. of the Ryukyus, Okinawa (Japan); Senjyu, Tomonobu [Faculty of Engineering, Univ. of the Ryukyus, Okinawa (Japan); Saber, Ahmed Yousuf [Operation Technology, Irvine, CA (United States)

    2013-04-15

    A digital H{sub {infinity}}controller for a permanent magnet synchronous generator (PMSG) based wind energy conversion system (WECS) is presented. Wind energy is an uncertain fluctuating resource which requires a tight control management. So, it is still an exigent task for the control design engineers. The conventional proportional-integral (PI) control is not ideal during high turbulence wind velocities, and the nonlinear behavior of the power converters. These are raising interest towards the robust control concepts. The robust design is to find a controller, for a given system, such that the closed-loop system becomes robust that assurance high-integrity and fault tolerant control system, robust H{sub {infinity}}control theory has befallen a standard design method of choice over the past two decades in industrial control applications. The robust H{sub {infinity}}control theory is also gaining eminence in the WECS. Due to the implementation complexity for the continuous H{sub {infinity}}controller, and availability of the high speedy micro-controllers, the design of a sample-data or a digital H{sub {infinity}}controller is very important for the realistic implementation. But there isn’t a single research to evaluate the performance of the digital H{sub {infinity}}controller for the WECS. In this paper, the proposed digital H{sub {infinity}}controller schemes comprise for the both generator and grid interactive power converters, and the control performances are compared with the conventional PI controller and the fuzzy controller. Simulation results confirm the efficacy of the proposed method Energies 2013, 6 2085 which are ensured the WECS stabilities, mitigate shaft stress, and improving the DC-link voltage and output power qualities.

  7. Design and Implement a Digital H∞ Robust Controller for a MW-Class PMSG-Based Grid-Interactive Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Tomonobu Senjyu

    2013-04-01

    Full Text Available A digital H∞ controller for a permanent magnet synchronous generator (PMSG based wind energy conversion system (WECS is presented. Wind energy is an uncertain fluctuating resource which requires a tight control management. So, it is still an exigent task for the control design engineers. The conventional proportional-integral (PI control is not ideal during high turbulence wind velocities, and the nonlinear behavior of the power converters. These are raising interest towards the robust control concepts. The robust design is to find a controller, for a given system, such that the closed-loop system becomes robust that assurance high-integrity and fault tolerant control system, robust H∞ control theory has befallen a standard design method of choice over the past two decades in industrial control applications. The robust H∞ control theory is also gaining eminence in the WECS. Due to the implementation complexity for the continuous H∞ controller, and availability of the high speedy micro-controllers, the design of a sample-data or a digital H∞ controller is very important for the realistic implementation. But there isn’t a single research to evaluate the performance of the digital H∞ controller for the WECS. In this paper, the proposed digital H∞ controller schemes comprise for the both generator and grid interactive power converters, and the control performances are compared with the conventional PI controller and the fuzzy controller. Simulation results confirm the efficacy of the proposed method Energies 2013, 6 2085 which are ensured the WECS stabilities, mitigate shaft stress, and improving the DC-link voltage and output power qualities.

  8. Ultra-Portable Smartphone Controlled Integrated Digital Microfluidic System in a 3D-Printed Modular Assembly

    Directory of Open Access Journals (Sweden)

    Mohamed Yafia

    2015-09-01

    Full Text Available Portable sensors and biomedical devices are influenced by the recent advances in microfluidics technologies, compact fabrication techniques, improved detection limits and enhanced analysis capabilities. This paper reports the development of an integrated ultraportable, low-cost, and modular digital microfluidic (DMF system and its successful integration with a smartphone used as a high-level controller and post processing station. Low power and cost effective electronic circuits are designed to generate the high voltages required for DMF operations in both open and closed configurations (from 100 to 800 V. The smartphone in turn commands a microcontroller that manipulate the voltage signals required for droplet actuation in the DMF chip and communicates wirelessly with the microcontroller via Bluetooth module. Moreover, the smartphone acts as a detection and image analysis station with an attached microscopic lens. The holder assembly is fabricated using three-dimensional (3D printing technology to facilitate rapid prototyping. The holder features a modular design that enables convenient attachment/detachment of a variety of DMF chips to/from an electrical busbar. The electrical circuits, controller and communication system are designed to minimize the power consumption in order to run the device on small lithium ion batteries. Successful controlled DMF operations and a basic colorimetric assay using the smartphone are demonstrated.

  9. DIGITAL SUBSTATION COMPONENT SYSTEM "SMART GRID"

    Directory of Open Access Journals (Sweden)

    V.I. Vasilchenko

    2014-12-01

    Full Text Available New production technologies of modern control systems have moved from the stage of research and experimentation into the stage of practical use. Modern communication standards for the exchange of information are developed and introduced. Digital devices, protectors and automation are widely used. There has been substantial development of hardware and software of control systems.

  10. Specification of requirements for upgrades using digital instrument and control systems. Report prepared within the framework of the international working group on nuclear power plant control and instrumentation

    International Nuclear Information System (INIS)

    1999-01-01

    The need to develop good specifications of requirements for instrument and control (I and C) systems applies throughout the world and is becoming more and more important as more upgrades are planned. Better guidance on how to develop good requirements specifications would support safer, more effective and more economical refits and upgrades. The need for this was pointed out by the IAEA International Working Group on Nuclear Power Plant Control and Instrumentation (IWG-NPPCI). This report is the result of a series of advisory and consultants meetings held by the IAEA in 1997 and 1998 in Vienna. The scope of the activities described covers a methodology for the determination of requirements and the development of the necessary specifications and plans needed through the life-cycle of digital instrumentation and control systems. It is restricted to technical aspects and indicates subjects which should be included in specifications and plans at different phases

  11. Evaluation of automatic exposure control system chamber for the dose optimization when examining pelvic in digital radiography.

    Science.gov (United States)

    Kim, Sung-Chul; Lee, Hae-Kag; Lee, Yang-Sub; Cho, Jae-Hwan

    2015-01-01

    We found a way to optimize the image quality and reduce the exposure dose of patients through the proper activity combination of the automatic exposure control system chamber for the dose optimization when examining the pelvic anteroposterior side using the phantom of the human body standard model. We set 7 combinations of the chamber of automatic exposure control system. The effective dose was yielded by measuring five times for each according to the activity combination of the chamber for the dose measurement. Five radiologists with more than five years of experience evaluated the image through picture archiving and communication system using double blind test while classifying the 6 anatomical sites into 3-point level (improper, proper, perfect). When only one central chamber was activated, the effective dose was found to be the highest level, 0.287 mSv; and lowest when only the top left chamber was used, 0.165 mSv. After the subjective evaluation by five panel members on the pelvic image was completed, there was no statistically meaningful difference between the 7 chamber combinations, and all had good image quality. When testing the pelvic anteroposterior side with digital radiography, we were able to reduce the exposure dose of patients using the combination of the top right side of or the top two of the chamber.

  12. General digitalized system on nuclear power plants

    International Nuclear Information System (INIS)

    Akagi, Katsumi; Kadohara, Hozumi; Taniguchi, Manabu

    2000-01-01

    Hitherto, instrumentation control system in a PWR nuclear power plant has stepwisely adopted digital technology such as application of digital instrumentation control device to ordinary use (primary/secondary system control device, and so on), application of CRT display system to monitoring function, and so forth, to realize load reduction of an operator due to expansion of operation automation range, upgrading of reliability and maintenance due to self-diagnosis function, reduction of mass in cables due to multiple transfer, and upgrading of visual recognition due to information integration. In next term PWR plant instrumentation control system, under consideration of application practice of conventional digital technology, application of general digitalisation system to adopt digitalisation of overall instrumentation control system containing safety protection system, and central instrumentation system (new type of instrumentation system) and to intend to further upgrade economics, maintenance, operability/monitoring under security of reliability/safety is planned. And, together with embodiment of construction program of the next-term plant, verification at the general digitalisation proto-system aiming at establishment of basic technology on the system is carried out. Then, here was described on abstract of the general digitalisation system and characteristics of a digital type safety protection apparatus to be adopted in the next-term plant. (G.K.)

  13. Digital processing data communication systems (bus systems)

    International Nuclear Information System (INIS)

    Fleck, K.

    1980-01-01

    After an introduction to the technology of digital processing data communication systems there are the following chapters: digital communication of processing data in automation technology, the technology of biserial communication, the implementaiton of a bus system, the data transmission of the TDC-2000 system of Honeywell's and the process bus CS 275 in the automation system TELEPERM M of Siemens AG. (WB) [de

  14. Component- and system-level degradation modeling of digital Instrumentation and Control systems based on a Multi-State Physics Modeling Approach

    International Nuclear Information System (INIS)

    Wang, Wei; Di Maio, Francesco; Zio, Enrico

    2016-01-01

    Highlights: • A Multi-State Physics Modeling (MSPM) framework for reliability assessment is proposed. • Monte Carlo (MC) simulation is utilized to estimate the degradation state probability. • Due account is given to stochastic uncertainty and deterministic degradation progression. • The MSPM framework is applied to the reliability assessment of a digital I&C system. • Results are compared with the results obtained with a Markov Chain Model (MCM). - Abstract: A system-level degradation modeling is proposed for the reliability assessment of digital Instrumentation and Control (I&C) systems in Nuclear Power Plants (NPPs). At the component level, we focus on the reliability assessment of a Resistance Temperature Detector (RTD), which is an important digital I&C component used to guarantee the safe operation of NPPs. A Multi-State Physics Model (MSPM) is built to describe this component degradation progression towards failure and Monte Carlo (MC) simulation is used to estimate the probability of sojourn in any of the previously defined degradation states, by accounting for both stochastic and deterministic processes that affect the degradation progression. The MC simulation relies on an integrated modeling of stochastic processes with deterministic aging of components that results to be fundamental for estimating the joint cumulative probability distribution of finding the component in any of the possible degradation states. The results of the application of the proposed degradation model to a digital I&C system of literature are compared with the results obtained by a Markov Chain Model (MCM). The integrated stochastic-deterministic process here proposed to drive the MC simulation is viable to integrate component-level models into a system-level model that would consider inter-system or/and inter-component dependencies and uncertainties.

  15. Digital fluorographic method and system

    International Nuclear Information System (INIS)

    Ledley, R.S.

    1985-01-01

    This invention relates to a digital fluorographic method and system, in particular a method and system which calls for the digitization and storage of first and second x-ray picture data derived before and after injection of a contrast medium into a subject. The digitized pictures are stored in separate memories in an associated system, and can be separately whole-picture processed to develop corresponding processed picture data. The resulting data are subtractively combined to produce data corresponding to a pictorial representation of differences between the x-ray picture before and after injection of the contrast medium

  16. Development of basic technology for instrumentation and control - Development of digital automatic supervisory limitation system and its design= validation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jung In; Chung, Sung Wook; Koh, Won Seok [Kyungwon University, Sungman (Korea, Republic of); Suh, Duk Young; Cheon, Sei Young [Kyunghee University, Seoul (Korea, Republic of); Lee, Sang Kyung; Kim, Sung Hun [Seoul National University, Seoul (Korea, Republic of)

    1995-07-01

    A major objective of the project is to develop a digital automatic supervisory limitation system and validate its design for the next generation= nuclear power plant. The limitation system assures that the plant does not exceed the operating limits by regulation the plant operations through on-line monitoring the operating margins of the critical parameters. A new conceptual model of power maneuverability has been proposed for the design of the limitation system and for its validation. Also, the limitation system monitors overall operation processes throughout a nuclear power plant by implementing hierarchical communication networks. Based on the conceptual design in software of the 1 st year results, the detailed design of the limitation system has been performed during the 2 nd year with constructing a prototype digital system. The system consists of the software module for plant simulation and the hardware module for implementation of limitation system and the associated interfaces in hardware. The limitation algorithm were implemented into the microprocessor and the interfaces were realized through the I/O modules. Also, these modules are incorporated into the communication networks. The products of the project could be directly applicable to the following nuclear unit adopting the limitation system, providing the bumpless transition to the commercial design phase. And the prototype evaluation scheme will be very useful for the succeeding studies related to the digital nuclear I and C fields, such as fault-tolerance design methods, software verification and validation and response time execution of digital systems. 69 refs., 3 tabs., 44 figs. (author)

  17. IAEA technical meeting on integrating analog and digital instrumentation and control systems in hybrid main control rooms at nuclear power plants. Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    The majority of instrumentation and control (I and C) equipment in nuclear power plants in the world was designed 30 to over 45 years ago with analog and relay components, and in some cases rudimentary digital technology. Today, most of these plants continue to operate with a substantial amount of this original I and C equipment that is or soon will be obsolete. Much of this equipment is approaching or exceeding its life expectancy, resulting in increasing maintenance efforts to sustain acceptable system performance. Decreasing availability of replacement parts, and the accelerating deterioration of the infrastructure of manufacturers that support analog technology, accentuate the obsolescence problems and cause operation and maintenance (O and M) cost increases. Refurbishments and license extensions mean that a plant must be supported longer, which will increase the obsolescence issues. In addition, the older technology limits the possibilities for adding new beneficial capabilities to the plant systems and interfaces. New technology provides the opportunity to improve plant performance, human system interface (HSI) functionality, and reliability; to enhance operator performance and reliability, and to address difficulties in finding young professionals with education and experience with older analog technology. Finally, there may be changes in regulatory requirements that could necessitate modernization activities. Modernization of I and C systems and components, using digital equipment to address these obsolescence issues and the need to improve plant performance (e.g., increase power output capacity, reliability, and availability) while maintaining high levels of safety, is a current major issue for nuclear power plants throughout the world. A number of nuclear power utilities are committing to major modernization programs. The need for this modernization will accelerate as plants age, obsolescence issues increase, plants receive license renewals, and features

  18. New digital control system for the operation of the Colombian research reactor IAN-R1; Nuevo sistema de control digital para la operacion del reactor de investigacion Colombiano IAN-R1

    Energy Technology Data Exchange (ETDEWEB)

    Celis del A, L.; Rivero, T.; Bucio, F.; Ramirez, R.; Segovia, A.; Palacios, J., E-mail: lina.celis@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2015-09-15

    En 2011, Mexico won the Colombian international tender for the renewal of instrumentation and control of the IAN-R1 Reactor, to Argentina and the United States. This paper presents the design criteria and the development made for the new digital control system installed in the Colombian nuclear reactor IAN-R1, which is based on a redundant and diverse architecture, which provides increased availability, reliability and safety in the reactor operation. This control system and associated instrumentation met all national export requirements, with the safety requirements established by the IAEA as well as the requirements demanded by the Colombian Regulatory Body in nuclear matter. On August 20, 2012, the Colombian IAN-R1 reactor reached its first criticality controlled with the new system developed at Instituto Nacional de Investigaciones Nucleares (ININ). On September 14, 2012, the new control system of the Colombian IAN-R1 reactor was officially handed over to the Colombian authorities, this being the first time that Mexico exported nuclear technology through the ININ. Currently the reactor is operating successfully with the new control system, and has an operating license for 5 years. (Author)

  19. Quantitative risk assessment of digitalized safety systems

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Sung Min; Lee, Sang Hun; Kang, Hym Gook [KAIST, Daejeon (Korea, Republic of); Lee, Seung Jun [UNIST, Ulasn (Korea, Republic of)

    2016-05-15

    A report published by the U.S. National Research Council indicates that appropriate methods for assessing reliability are key to establishing the acceptability of digital instrumentation and control (I and C) systems in safety-critical plants such as NPPs. Since the release of this issue, the methodology for the probabilistic safety assessment (PSA) of digital I and C systems has been studied. However, there is still no widely accepted method. Kang and Sung found three critical factors for safety assessment of digital systems: detection coverage of fault-tolerant techniques, software reliability quantification, and network communication risk. In reality the various factors composing digitalized I and C systems are not independent of each other but rather closely connected. Thus, from a macro point of view, a method that can integrate risk factors with different characteristics needs to be considered together with the micro approaches to address the challenges facing each factor.

  20. Microprocessor controlled digital period meter

    International Nuclear Information System (INIS)

    Keefe, D.J.; McDowell, W.P.; Rusch, G.K.

    1980-01-01

    A microprocessor controlled digital period meter has been developed and tested operationally on a reactor at Argonne National Laboratory. The principle of operation is the mathematical relationship between asymptotic periods and pulse counting circuitry. This relationship is used to calculate and display the reactor periods over a range of /plus or minus/1 second to /plus or minus/999 seconds. The time interval required to update each measurement automatically varies from 8 seconds at the lowest counting rates to 2 seconds at higher counting rates. The paper will describe hardware and software design details and show the advantages of this type of Period Meter over the conventional circuits. 1 ref

  1. Design considerations for a digital feedback system to control self-bunching in ion-storage rings

    Directory of Open Access Journals (Sweden)

    V. Ziemann

    2001-04-01

    Full Text Available We discuss the feasibility of a digital feedback system to cure self-bunching of the electron-cooled coasting ion beam in ion-storage rings such as CELSIUS [S. Holm, A. Johansson, S. Kullander, and D. Reistad, Phys. Scr. 34, 513–532 (1986]. Such a system is based on a fast digital filter that acts as a tunable artificial wake potential. It may also aid stable operation of accumulator rings for future spallation neutron sources or heavy ion rings used for inertial fusion energy production.

  2. Calculation of Digital Control Circuits using Scilab Environment

    Directory of Open Access Journals (Sweden)

    Petru Chioncel

    2015-09-01

    Full Text Available The paper presents the computing of digital control circuits using Scilab environment. It exemplifies the influence of the sampling time in case of a transfer system described by a PT3 element composed of one PT1 and one PT2 element. For a continuous control system, the transfer function in z is computed and replaced with a digital control system. The presented calculation, done in Scilab, highlights the test responses of the process evidencing the systems performances.

  3. Controlled sharing of personal content using digital rights management

    NARCIS (Netherlands)

    Conrado, C.; Petkovic, M.; Veen, van der M.; Velde, van der W.H.

    2006-01-01

    This paper describes a system which allows controlled distribution of personal digital content by users. The system extends an existing Digital Rights Management system for the protection of commercial copyrighted content by essentially allowing users to become content providers. This fact, however,

  4. Digital subtraction angiography system evaluation with phantoms

    International Nuclear Information System (INIS)

    Wenstrup, R.S.; Sweeney, K.P.; Scholz, F.J.

    1985-01-01

    Advances in digital subtraction angiography imaging demonstrate the need for critical evaluation of the performance of digital subtraction equipment. The design of a phantom set for noninvasive assessment of the imaging quality of digital subtraction equipment is described; components include a remotely controlled transport system and individual patterns to evaluate the contrast and detail properties of the image intensifier, low-contrast sensitivity and resolution of the system, geometric distortion of image, linearity, mechanical and electronic stability of equipment, and effects of bone and bowel gas on iodine perception. The performance of an add-on digital radiographic system is presented, along with radiation exposure levels at the image intensifier for a range of radiographic techniques

  5. Review report: safety and reliability issues on digital instrumentation and control systems in nuclear power plants and United States Nuclear Regulatory Commission`s dispositions

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Norio; Suzudo, Tomoaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-09-01

    Recently, digital instrumentation and control (I and C) systems have been applied to nuclear power plants (NPPs) in various countries. Introduction of digital I and C systems, however, raises special issues on design, implementation, safety and licensing. Since FY 1997, the Japan Atomic Energy Research Institute (JAERI) has been carrying out a project, Study on Reliability of Digital I and C Systems, which includes extensive reviews of design approaches, technical standards, regulatory processes, especially, in the United States. This report summarizes the results from the study of National Research Council (NRC) and the U.S. Nuclear Regulatory Commission`s (USNRC`s) responses to the recommendations made by the NRC`s study. That study identified six technical key issues (system aspects of digital I and C technology, software quality assurance, common-mode software failure potential, safety and reliability assessment methods, human factors and man-machine interface, dedication of commercial off-the-shelf hardware and software) and two strategic key issues (case-by-case licensing process, adequacy of technical infrastructure) that arise from the introduction of digital I and C technology and then, made recommendations to the USNRC for coping with digital I and C applications. The USNRC responded to each recommendation and showed their own dispositions in which the USNRC agreed with most of the recommendations. In Japan, it is expected that introduction of digital I and C technology is inevitable in NPPs because the vendors are gradually discontinuing support and stocking of analog components. To cope with such situations, there is a need to develop and update the standards and guidelines applicable to digital I and C technology. The key issues and the USNRC`s dispositions provided in this report is believed to be useful for developing and updating them. (J.P.N.)

  6. Review report: safety and reliability issues on digital instrumentation and control systems in nuclear power plants and United States Nuclear Regulatory Commission's dispositions

    International Nuclear Information System (INIS)

    Watanabe, Norio; Suzudo, Tomoaki

    1998-09-01

    Recently, digital instrumentation and control (I and C) systems have been applied to nuclear power plants (NPPs) in various countries. Introduction of digital I and C systems, however, raises special issues on design, implementation, safety and licensing. Since FY 1997, the Japan Atomic Energy Research Institute (JAERI) has been carrying out a project, Study on Reliability of Digital I and C Systems, which includes extensive reviews of design approaches, technical standards, regulatory processes, especially, in the United States. This report summarizes the results from the study of National Research Council (NRC) and the U.S. Nuclear Regulatory Commission's (USNRC's) responses to the recommendations made by the NRC's study. That study identified six technical key issues (system aspects of digital I and C technology, software quality assurance, common-mode software failure potential, safety and reliability assessment methods, human factors and man-machine interface, dedication of commercial off-the-shelf hardware and software) and two strategic key issues (case-by-case licensing process, adequacy of technical infrastructure) that arise from the introduction of digital I and C technology and then, made recommendations to the USNRC for coping with digital I and C applications. The USNRC responded to each recommendation and showed their own dispositions in which the USNRC agreed with most of the recommendations. In Japan, it is expected that introduction of digital I and C technology is inevitable in NPPs because the vendors are gradually discontinuing support and stocking of analog components. To cope with such situations, there is a need to develop and update the standards and guidelines applicable to digital I and C technology. The key issues and the USNRC's dispositions provided in this report is believed to be useful for developing and updating them. (J.P.N.)

  7. Digitally controlled twelve-pulse firing generator

    International Nuclear Information System (INIS)

    Berde, D.; Ferrara, A.A.

    1981-01-01

    Control System Studies for the Tokamak Fusion Test Reactor (TFTR) indicate that accurate thyristor firing in the AC-to-DC conversion system is required in order to achieve good regulation of the various field currents. Rapid update and exact firing angle control are required to avoid instabilities, large eddy currents, or parasitic oscillations. The Prototype Firing Generator was designed to satisfy these requirements. To achieve the required /plus or minus/0.77/degree/firing accuracy, a three-phase-locked loop reference was designed; otherwise, the Firing Generator employs digital circuitry. The unit, housed in a standard CAMAC crate, operates under microcomputer control. Functions are performed under program control, which resides in nonvolatile read-only memory. Communication with CICADA control system is provided via an 11-bit parallel interface

  8. Technical self reliance of digital safety systems

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Kee Choon; Lee, Dong Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Kook Hun [Doosan Heavy Industries and Construction, Changwon (Korea, Republic of); Choi, Seung Gap [POSCON, Pohang (Korea, Republic of)

    2009-04-15

    This paper summarizes the development results of the Korea Nuclear Instrumentation and Control System (KNICS) project sponsored by the Korean government. In this project, Man Machine Interface System (MMIS) architecture, two digital platforms, and several control systems are developed. One platform is a programmable Logic Controller (PLC) for a safety system and another platform is a Distributed Control System (DCS) for a non safety system. With the POSAFE Q PLC, a Reactor Protection System (RPS) and an Engineered Safety Feature Component Control System (ESF CCS) are developed. A Power Control System (PCS) is developed based on the DCS. The safety grade platform and the digital safety systems obtained approval for the Topical Report from the Korean regulatory body in February of 2009. Also a Korean utility and a vendor company determined KNICS results to apply them to the planned Nuclear Power Plant (NPP) in March 2009. This paper introduces the technical self reliance experiences of the safety grade platform and the digital safety systems developed in the KNICS R and D project.

  9. Digital controlled pulsed electric system of the ETE tokamak. First report

    International Nuclear Information System (INIS)

    Barbosa, Luis Felipe de F.P.W.; Del Bosco, Edson

    1997-01-01

    This reports presents a summary on the thermonuclear fusion and application for energy supply purposes. The tokamak device operation and the magnetic field production systems are described. The ETE tokamak is a small aspect ratio device designed for plasma physics and thermonuclear fusion studies, which presently is under construction at the Laboratorio Associado de Plasma (LAP), Instituto Nacional de Pesquisas Espaciais (INPE) - S.J. dos Campos - S. Paulo. (author)

  10. Digitizing instrumentation and control systems in nuclear power plants. DAtF autumn meeting Leittec '96, October 8, 1996 in Koenigswinter

    International Nuclear Information System (INIS)

    Aleite, W.

    1997-01-01

    Recently, digitization for upgrading and retrofitting of instrumentation and control systems has been extended to German nuclear power plants, and initial action to commence modification started with a very suitable system, the limiters of the Neckar-1 reactor unit of GKN. This action is generally welcomed. Systems of the control room of relevance to safety -even if not belonging to priority classes - are systems for process information for example, or operator guidance, as well as diagnostic systems for inspection and maintenance. (orig./DG) [de

  11. Digital controlled pulsed electric system of the ETE tokamak. First report; Sistema eletrico pulsado com controle digital do Tokamak ETE (experimento Tokamak esferico). Primeiro relatorio

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Luis Felipe de F.P.W.; Del Bosco, Edson

    1998-12-31

    This reports presents a summary on the thermonuclear fusion and application for energy supply purposes. The tokamak device operation and the magnetic field production systems are described. The ETE tokamak is a small aspect ratio device designed for plasma physics and thermonuclear fusion studies, which presently is under construction at the Laboratorio Associado de Plasma (LAP), Instituto Nacional de Pesquisas Espaciais (INPE) - S.J. dos Campos - S. Paulo. (author) 55 refs., 40 figs.

  12. Digital controlled pulsed electric system of the ETE tokamak. First report; Sistema eletrico pulsado com controle digital do Tokamak ETE (experimento Tokamak esferico). Primeiro relatorio

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Luis Felipe de F.P.W.; Del Bosco, Edson

    1997-12-31

    This reports presents a summary on the thermonuclear fusion and application for energy supply purposes. The tokamak device operation and the magnetic field production systems are described. The ETE tokamak is a small aspect ratio device designed for plasma physics and thermonuclear fusion studies, which presently is under construction at the Laboratorio Associado de Plasma (LAP), Instituto Nacional de Pesquisas Espaciais (INPE) - S.J. dos Campos - S. Paulo. (author) 55 refs., 40 figs.

  13. Administration and maintenance of distributed control digital systems; Administracion y mantenimiento de sistemas digitales de control distribuido (SDCD)

    Energy Technology Data Exchange (ETDEWEB)

    Ferreiro, Jorge M. [Administracion Nacional de Combustibles Alcohol y Portland (ANCAP), Montevideo (Uruguay)

    1998-07-01

    The demand for increased competitiveness has produced a growing presence of Distributed Control Systems (DCS) in the industrial environment. Regardless of size and function, all DCSs have in common very high availability and reliability requirements, and significant hardware, software and configuration complexity. The persons in charge of DCS management and maintenance are thus faced with a task of great responsibility and complexity, with little support in the form of voluminous, complex, non methodological documentation. This work aims to help these persons by giving them advice taken from real-life DCS management experience. As an initial framework, concepts on availability, fault tolerance, modularity, redundancy and maintainability are introduced. Then a DCS maintenance methodology is presented: teamwork, attitude, how to carry on routine work and how to face emergencies. Advice is given on how to develop maintenance procedures based on DCS maintenance tools, with an emphasis on using the DCS event and performance information for predictive maintenance. An overview of DCS hardware and software configuration management. (author)

  14. Failure Modes Taxonomy for Reliability Assessment of Digital Instrumentation and Control Systems for Probabilistic Risk Analysis - Failure modes taxonomy for reliability assessment of digital I and C systems for PRA

    International Nuclear Information System (INIS)

    Amri, A.; Blundell, N.; ); Authen, S.; Betancourt, L.; Coyne, K.; Halverson, D.; Li, M.; Taylor, G.; Bjoerkman, K.; Brinkman, H.; Postma, W.; Bruneliere, H.; Chirila, M.; Gheorge, R.; Chu, L.; Yue, M.; Delache, J.; Georgescu, G.; Deleuze, G.; Quatrain, R.; Thuy, N.; Holmberg, J.-E.; Kim, M.C.; Kondo, K.; Mancini, F.; Piljugin, E.; Stiller, J.; Sedlak, J.; Smidts, C.; Sopira, V.

    2015-01-01

    Digital protection and control systems appear as upgrades in older nuclear power plants (NPP), and are commonplace in new NPPs. To assess the risk of NPP operation and to determine the risk impact of digital systems, there is a need to quantitatively assess the reliability of the digital systems in a justifiable manner. Due to the many unique attributes of digital systems (e.g., functions are implemented by software, units of the system interact in a communication network, faults can be identified and handled online), a number of modelling and data collection challenges exist, and international consensus on the reliability modelling has not yet been reached. The objective of the task group called DIGREL has been to develop a taxonomy of failure modes of digital components for the purposes of probabilistic risk analysis (PRA). An activity focused on the development of a common taxonomy of failure modes is seen as an important step towards standardised digital instrumentation and control (I and C) reliability assessment techniques for PRA. Needs from PRA has guided the work, meaning, e.g., that the I and C system and its failures are studied from the point of view of their functional significance point of view. The taxonomy will be the basis of future modelling and quantification efforts. It will also help to define a structure for data collection and to review PRA studies. The proposed failure modes taxonomy has been developed by first collecting examples of taxonomies provided by the task group organisations. This material showed some variety in the handling of I and C hardware failure modes, depending on the context where the failure modes have been defined. Regarding the software part of I and C, failure modes defined in NPP PRAs have been simple - typically a software CCF failing identical processing units. The DIGREL task group has defined a new failure modes taxonomy based on a hierarchical definition of five levels of abstraction: 1. system level (complete

  15. An approach based on defense-in-depth and diversity (3D) for the reliability assessment of digital instrument and control systems of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Paulo Adriano da; Saldanha, Pedro L.C., E-mail: pasilva@cnen.gov.b, E-mail: Saldanha@cnen.gov.b [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil). Coord. Geral de Reatores Nucleares; Melo, Paulo F. Frutuoso e, E-mail: frutuoso@nuclear.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao em Engenharia. Programa de Engenharia Nuclear; Araujo, Ademir L. de [Associacao Brasileira de Ensino Universitario (UNIABEU), Angra dos Reis, RJ (Brazil)

    2011-07-01

    The adoption of instrumentation and control (I and C) digital technology has been slower in nuclear power plants. The reason has been unfruitful efforts to obtain evidence in order to prove that I and C systems can be used in nuclear safety systems, for example, the Reactor Protection System (RPS), ensuring the proper operation of all its functions. This technology offers a potential improvement for safety and reliability. However, there still no consensus about the model to be adopted for digital systems software to be used in reliability studies. This paper presents the 3D methodology approach to assess digital I and C reliability. It is based on the study of operational events occurring in NPPs. It is easy to identify, in general, the level of I and C system reliability, showing its key vulnerabilities, enabling to trace regulatory actions to minimize or avoid them. This approach makes it possible to identify the main types of digital I and C system failure, with the potential for common cause failures as well as evaluating the dominant failure modes. The MAFIC-D software was developed to assist the implementation of the relationships between the reliability criteria, the analysis of relationships and data collection. The results obtained through this tool proved to be satisfactory and complete the process of regulatory decision-making from licensing I and C digital of NPPs and call still be used to monitor the performance of I and C digital post-licensing during the lifetime of the system, providing the basis for the elaboration of checklists of regulatory inspections. (author)

  16. An approach based on defense-in-depth and diversity (3D) for the reliability assessment of digital instrument and control systems of nuclear power plants

    International Nuclear Information System (INIS)

    Silva, Paulo Adriano da; Saldanha, Pedro L.C.

    2011-01-01

    The adoption of instrumentation and control (I and C) digital technology has been slower in nuclear power plants. The reason has been unfruitful efforts to obtain evidence in order to prove that I and C systems can be used in nuclear safety systems, for example, the Reactor Protection System (RPS), ensuring the proper operation of all its functions. This technology offers a potential improvement for safety and reliability. However, there still no consensus about the model to be adopted for digital systems software to be used in reliability studies. This paper presents the 3D methodology approach to assess digital I and C reliability. It is based on the study of operational events occurring in NPPs. It is easy to identify, in general, the level of I and C system reliability, showing its key vulnerabilities, enabling to trace regulatory actions to minimize or avoid them. This approach makes it possible to identify the main types of digital I and C system failure, with the potential for common cause failures as well as evaluating the dominant failure modes. The MAFIC-D software was developed to assist the implementation of the relationships between the reliability criteria, the analysis of relationships and data collection. The results obtained through this tool proved to be satisfactory and complete the process of regulatory decision-making from licensing I and C digital of NPPs and call still be used to monitor the performance of I and C digital post-licensing during the lifetime of the system, providing the basis for the elaboration of checklists of regulatory inspections. (author)

  17. The influence of the analog-to-digital conversion error on the JT-60 plasma position/shape feedback control system

    International Nuclear Information System (INIS)

    Yoshida, Michiharu; Kurihara, Kenichi

    1995-12-01

    In the plasma feedback control system (PFCS) and the direct digital controller (DDC) for the poloidal field coil power supply in the JT-60 tokamak, it is necessary to observe signals of all the poloidal field coil currents. Each of the signals, originally measured by a single sensor, is distributed to the PFCS and DDC through different cable routes and different analog-to-digital converters from each other. This produces the conversion error to the amount of several bits. Consequently, proper voltage from feedback calculation cannot be applied to the coil, and hence the control performance is possibly supposed to deteriorate to a certain extent. This paper describes how this error makes an influence on the plasma horizontal position control and how to improve the deteriorated control performance. (author)

  18. Development of prototype digital LLRF system at RRCAT

    International Nuclear Information System (INIS)

    Tiwari, Nitesh; Bagduwal, Pritam S.; Sharma, Dheeraj; Chakraborty, Shoubhik; Lad, Mahendra; Hannurkar, P.R.

    2013-01-01

    RF field is used in accelerator to accelerate the charge particles. The beam parameters depend highly on the stability of the RF field. Due to dynamic beam loading conditions the variations in RF parameters of accelerating structures needs to be controlled precisely, hence low level RF feedback control system plays vital role. Considering revolutionary development in the field of digital electronics and inherent advantages of digital systems, digital LLRF control system work was taken up. The digital LLRF system consists of two major units namely RF processing and digital processing. RF processing unit uses I/Q modulator for amplitude and phase control. This unit provides synchronized clock using ÷16 pre-scalar and also performs up conversion and down conversion for synchronized LO and IF generation respectively, along with required amplification and filtering. Digital processing unit takes down converted IF signal with appropriate sampling rate for I/Q detection. To extract the amplitude and phase information I/Q data is digitally filtered and processed using CORDIC algorithm in FPGA. I/Q modulator is used for controlling the amplitude and phase of RF field. Prototype development of digital LLRF control system for 325 MHz, 650 MHz is in progress. Digital LLRF system at 505 MHz has been installed in one RF station of Indus-2 RF system. In this paper development of prototype Digital LLRF system at RFSD, Raja Ramanna Centre for Advanced Technology and results are presented. (author)

  19. DropBot: An open-source digital microfluidic control system with precise control of electrostatic driving force and instantaneous drop velocity measurement

    International Nuclear Information System (INIS)

    Fobel, Ryan; Fobel, Christian; Wheeler, Aaron R.

    2013-01-01

    We introduce DropBot: an open-source instrument for digital microfluidics (http://microfluidics.utoronto.ca/dropbot). DropBot features two key functionalities for digital microfluidics: (1) real-time monitoring of instantaneous drop velocity (which we propose is a proxy for resistive forces), and (2) application of constant electrostatic driving forces through compensation for amplifier-loading and device capacitance. We anticipate that this system will enhance insight into failure modes and lead to new strategies for improved device reliability, and will be useful for the growing number of users who are adopting digital microfluidics for automated, miniaturized laboratory operation.

  20. Immunizing digital systems against electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1993-01-01

    This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Second, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced

  1. Immunizing digital systems against electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1993-01-01

    This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Secondly, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced

  2. Direct digital temperature control of the A-1 nuclear reactor

    International Nuclear Information System (INIS)

    Karpeta, C.

    1975-01-01

    The application is described of one of the modern control methods for designing an experimental digital temperature control system for heavy water moderated gas cooled reactors. The synthesis of the optimal stochastic regulator for reactor control in the area of the rated steady state was carried out using the method of dynamic programming and the Kalman filter technique. The analysis of the feedback circuit was conducted using control simulation on a universal digital computer. Results and experience are summed up. (author)

  3. Digital radiology and digitally formatted image management systems

    International Nuclear Information System (INIS)

    Cox, G.G.; Dwyer, S.J. III; Templeton, A.W.

    1987-01-01

    The number of diagnostic examinations performed with digitally formatted imaging equipment is increasing. Digital general-purpose and fluoroscopic radiology systems are being clinically evaluated. Digitizing conventional x-ray films, such as mammograms, frequently improves the diagnostic quality of the images. The digitizing process with laser has also afforded the opportunity to document required spatial resolution for digital imaging and network systems. The use of digitally formatted image instrumentation imposes new requirements on the acquisition, display and manipulation, transmission, hard copy image recording, and archiving of diagnostic data. Networking of digitally formatted image data offers many advantages for managing digital information. This paper identifies and describes digital radiographic systems. Parameters required for designing and implementing a digital image management system are outlined. Spatial and contrast resolution requirements are identified. The key parameters include the amount of image data generated each working day, the retrieval rate of the generated data, the display hardware and software needed for interactive diagnosis display stations, the requirements for analog hard copy generation, and on-line and long-term archiving requirements. These image management systems are often called PACS (Picture Archiving and Communication Systems)

  4. Terminal area automatic navigation, guidance and control research using the Microwave Landing System (MLS). Part 5: Design and development of a Digital Integrated Automatic Landing System (DIALS) for steep final approach using modern control techniques

    Science.gov (United States)

    Halyo, N.

    1983-01-01

    The design and development of a 3-D Digital Integrated Automatic Landing System (DIALS) for the Terminal Configured Vehicle (TCV) Research Aircraft, a B-737-100 is described. The system was designed using sampled data Linear Quadratic Gaussian (LOG) methods, resulting in a direct digital design with a modern control structure which consists of a Kalman filter followed by a control gain matrix, all operating at 10 Hz. DIALS uses Microwave Landing System (MLS) position, body-mounted accelerometers, as well as on-board sensors usually available on commercial aircraft, but does not use inertial platforms. The phases of the final approach considered are the localizer and glideslope capture which may be performed simultaneously, localizer and steep glideslope track or hold, crab/decrab and flare to touchdown. DIALS captures, tracks and flares from steep glideslopes ranging from 2.5 deg to 5.5 deg, selected prior to glideslope capture. Digital Integrated Automatic Landing System is the first modern control design automatic landing system successfully flight tested. The results of an initial nonlinear simulation are presented here.

  5. CANDU Digital Control Computer upgrade options

    International Nuclear Information System (INIS)

    De Jong, M.S.; De Grosbois, J.; Qian, T.

    1997-01-01

    This paper reviews the evolution of Digital Control Computers (DCC) in CANDU power plants to the present day. Much of this evolution has been to meeting changing control or display requirements as well as the replacement of obsolete, or old and less reliable technology with better equipment that is now available. The current work at AECL and Canadian utilities to investigate DCC upgrade options, alternatives, and strategies are examined. The dependence of a particular upgrade strategy on the overall plant refurbishment plans are also discussed. Presently, the upgrade options range from replacement of individual obsolete system components, to replacement of the entire DCC hardware without changing the software, to complete replacement of the DCCs with a functionally equivalent system using new control computer equipment and software. Key issues, constraints and objectives associated with these DCC upgrade options are highlighted. (author)

  6. Digital control of electric drives

    CERN Document Server

    Koziol, R; Szklarski, L

    1992-01-01

    The electromechanical systems employed in different branches of industry are utilized most often as drives of working machines which must be fed with electric energy in a continuous, periodic or even discrete way. Some of these machines operate at constant speed, others require wide and varying energy control. In many designs the synchronous cooperation of several electric drives is required in addition to the desired dynamic properties. For these reasons the control of the cooperation and dynamics of electromechanical systems requires the use of computers.This book adopts an unusual approach

  7. Two viewpoints for software failures and their relation in probabilistic safety assessment of digital instrumentation and control systems

    International Nuclear Information System (INIS)

    Kim, Man Cheol

    2015-01-01

    As the use of digital systems in nuclear power plants increases, the reliability of the software becomes one of the important issues in probabilistic safety assessment. In this paper, two viewpoints for a software failure during the operation of a digital system or a statistical software test are identified, and the relation between them is provided. In conventional software reliability analysis, a failure is mainly viewed with respect to the system operation. A new viewpoint with respect to the system input is suggested. The failure probability density functions for the two viewpoints are defined, and the relation between the two failure probability density functions is derived. Each failure probability density function can be derived from the other failure probability density function by applying the derived relation between the two failure probability density functions. The usefulness of the derived relation is demonstrated by applying it to the failure data obtained from the software testing of a real system. The two viewpoints and their relation, as identified in this paper, are expected to help us extend our understanding of the reliability of safety-critical software. (author)

  8. Certification of digital system software

    International Nuclear Information System (INIS)

    Waclo, J.; Cook, B.; Adomaitis, D.

    1991-01-01

    The activities involved in the successful application of digital systems to Nuclear Protection functions is not achieved through happenstance. At Westinghouse there has been a longstanding program to utilize digital state of the art technology for protection system advancement. Thereby gaining the advantages of increased system reliability, performance, ease of operation and reduced maintenance costs. This paper describes the Westinghouse background and experience in the safety system software development process, including Verification and Validation, and its application to protection system qualification and the successful use for licensing the Eagle 21 Digital Process Protection System Upgrade. In addition, the lessons learned from this experience are discussed from the perspective of improving the development process through applying feedback of the measurements made on the process and the software product quality. The goal of this process optimization is to produce the highest possible software quality while recognizing the real world constraints of available resources, project schedule and the regulatory policies that are customary in the nuclear industry

  9. An Embedded Based Digital Controller for Thermal Process

    Directory of Open Access Journals (Sweden)

    A. Lakshmi Sangeetha

    2008-01-01

    Full Text Available This paper describes a low cost virtual instrumentation (VI system to monitor and control the electrically heated water bath temperature. The PIC16F877 based digital microcontroller is used as thermostat which controls and monitors the temperature. The digital controller also allows the user to modify the sensor (PT100 calibration data values if necessary. The developed programmable on/off control function provides on-line display of measuring temperature, set point as well as the control function output plots through the parallel port. This bus interaction is realized in Visual Basic/Assembly Language and uses a 16 bit, 10 ms sampling analog-to-digital converter (ADS 7805 for monitoring and controlling the parameters of the temperature local digital controller.

  10. Development and Flight Evaluation of an Emergency Digital Flight Control System Using Only Engine Thrust on an F-15 Airplane

    Science.gov (United States)

    Burcham, Frank W., Jr.; Maine, Trindel A.; Fullerton, C. Gordon; Webb, Lannie Dean

    1996-01-01

    A propulsion-controlled aircraft (PCA) system for emergency flight control of aircraft with no flight controls was developed and flight tested on an F-15 aircraft at the NASA Dryden Flight Research Center. The airplane has been flown in a throttles-only manual mode and with an augmented system called PCA in which pilot thumbwheel commands and aircraft feedback parameters were used to drive the throttles. Results from a 36-flight evaluation showed that the PCA system can be used to safety land an airplane that has suffered a major flight control system failure. The PCA system was used to recover from a severe upset condition, descend, and land. Guest pilots have also evaluated the PCA system. This paper describes the principles of throttles-only flight control; a history of loss-of-control accidents; a description of the F-15 aircraft; the PCA system operation, simulation, and flight testing; and the pilot comments.

  11. A customized digital monitoring and display system for nonpower reactors

    International Nuclear Information System (INIS)

    Ficaro, E.P.; Wehe, D.K.

    1989-01-01

    A digital data acquisition system for monitoring plant variables has been designed and implemented at the University of Michigan's Ford Nuclear Reactor (FNR), a 2-MW open-pool research reactor. The digital data provided by this system will be useful for: improved operator training, real-time experimental calculations, noise analysis, closed-loop control, and expert system applications. This paper describes the analog-to-digital (A/D) transitions and the associated applications and benefits experienced

  12. Development of new process network for gas chromatograph and analyzers connected with SCADA system and Digital Control Computers at Cernavoda NPP Unit 1

    International Nuclear Information System (INIS)

    Deneanu, Cornel; Popa Nemoiu, Dragos; Nica, Dana; Bucur, Cosmin

    2007-01-01

    The continuous monitoring of gas mixture concentrations (deuterium/ hydrogen/oxygen/nitrogen) accumulated in 'Moderator Cover Gas', 'Liquid Control Zone' and 'Heat Transport D 2 O Storage Tank Cover Gas', as well as the continuous monitoring of Heavy Water into Light Water concentration in 'Boilers Steam', 'Boilers Blown Down', 'Moderator heat exchangers', and 'Recirculated Water System', sensing any leaks of Cernavoda NPP U1 led to requirement of developing a new process network for gas chromatograph and analyzers connected to the SCADA system and Digital Control Computers of Cernavoda NPP Unit 1. In 2005 it was designed and implemented the process network for gas chromatograph which connected the gas chromatograph equipment to the SCADA system and Digital Control Computers of the Cernavoda NPP Unit 1. Later this process network for gas chromatograph has been extended to connect the AE13 and AE14 Fourier Transform Infrared (FTIR) analyzers with either. The Gas Chromatograph equipment measures with best accuracy the mixture gases (deuterium/ hydrogen/oxygen/nitrogen) concentration. The Fourier Transform Infrared (FTIR) AE13 and AE14 Analyzers measure the Heavy Water into Light Water concentration in Boilers Steam, Boilers BlownDown, Moderator heat exchangers, and Recirculated Water System, monitoring and signaling any leaks. The Gas Chromatograph equipment and Fourier Transform Infrared (FTIR) AE13 and AE14 Analyzers use the new OPC (Object Link Embedded for Process Control) technologies available in ABB's VistaNet network for interoperability with automation equipment. This new process network has interconnected the ABB chromatograph and Fourier Transform Infrared analyzers with plant Digital Control Computers using new technology. The result was an increased reliability and capability for inspection and improved system safety

  13. Digital control of plasma position in Damavand tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Emami, M.; Babazadeh, A.R.; Roshan, M.V.; Memarzadeh, M.; Habibi, H. [Atomic Energy Organization of Iran (AEOI), Tehran (Iran, Islamic Republic of). Nuclear Fusion Research Center. Plasma Physics Lab.

    2002-03-01

    Plasma position control is one of the important issues in the design and operation of tokamak fusion research device. Since a tokamak is basically an electrical system consisting of power supplies, coils, plasma and eddy currents, a model in which these components are treated as an electrical circuits is used in designing Damavand plasma position control system. This model is used for the simulation of the digital control system and its parameters have been verified experimentally. In this paper, the performance of a high-speed digital controller as well as a simulation study and its application to the Damavand tokamak is discussed. (author)

  14. The cyclical monitoring system for digital power supplies at SSRF

    International Nuclear Information System (INIS)

    Tang Junlong; Li Deming; Shen Tianjian

    2009-01-01

    Based on available digital PS testing system and long-distance monitoring hardwares, the cyclical monitoring system for digital power supplies (PS) was developed at SSRF. Two models, i.e.long-distance cyclical monitoring and local cyclical monitoring, were established. The software developed in LabVIEW language was applied to the two models without any user interface modification. The user interface is simple. The system is suitable for debugging the digital PSs during long-distance monitoring and examining the performance. The long-distance model imitates the digital PSs' status for fault analysis and communication between the digital PS and the centre control room. The local model simultaneously examines stability of 18 new PSs for 24 h, monitors the PS controller, and detects malfunction. Parameters and status of the controller can be stored in Excel or Text file. The two models have been used at SSRF for monitoring the digital PSs. (authors)

  15. On the simulation of transients and accidents in PWRs with digital instrumentation and control using an LQR digital controller

    International Nuclear Information System (INIS)

    Alvarenga, M.A.B.; Melo, P.F. Frutuoso e; Medeiros, J.A.C.C.; Oliva, J.J. Rivero

    2015-01-01

    New nuclear power plant designs are including integrated I and C digital systems for protection, control, alarming and monitoring. Existing operating nuclear power plants, as is the case of Angra 1 nuclear power plant, have to consider the replacement of their I and C analog systems by digital systems for retrofitting their facilities. However, before replacing the analog control loops by digital ones it is necessary to design and evaluate their performance, which requires modeling of the plant and its control system with extensive simulations under several normal and abnormal operation conditions. This paper discusses the use of a linear quadratic regulator (LQR) digital controller for evaluating the plant stability behavior before the actuation of the reactor protection system. The objective is to evaluate the effect of digital controllers on plant behavior for several transients and accident conditions. For this purpose, a numerical model was developed and implemented as a MatlabTM tool. This paper discusses an adequate framework in order to simulate a set of transients and accidents that constitute the design basis in the final safety analysis report of PWR power plants to evaluate the performance of digital controllers such as LQR regulators.(author)

  16. Implementation of Adaptive Digital Controllers on Programmable Logic Devices

    Science.gov (United States)

    Gwaltney, David A.; King, Kenneth D.; Smith, Keary J.; Monenegro, Justino (Technical Monitor)

    2002-01-01

    Much has been made of the capabilities of FPGA's (Field Programmable Gate Arrays) in the hardware implementation of fast digital signal processing. Such capability also makes an FPGA a suitable platform for the digital implementation of closed loop controllers. Other researchers have implemented a variety of closed-loop digital controllers on FPGA's. Some of these controllers include the widely used proportional-integral-derivative (PID) controller, state space controllers, neural network and fuzzy logic based controllers. There are myriad advantages to utilizing an FPGA for discrete-time control functions which include the capability for reconfiguration when SRAM-based FPGA's are employed, fast parallel implementation of multiple control loops and implementations that can meet space level radiation tolerance requirements in a compact form-factor. Generally, a software implementation on a DSP (Digital Signal Processor) or microcontroller is used to implement digital controllers. At Marshall Space Flight Center, the Control Electronics Group has been studying adaptive discrete-time control of motor driven actuator systems using digital signal processor (DSP) devices. While small form factor, commercial DSP devices are now available with event capture, data conversion, pulse width modulated (PWM) outputs and communication peripherals, these devices are not currently available in designs and packages which meet space level radiation requirements. In general, very few DSP devices are produced that are designed to meet any level of radiation tolerance or hardness. The goal of this effort is to create a fully digital, flight ready controller design that utilizes an FPGA for implementation of signal conditioning for control feedback signals, generation of commands to the controlled system, and hardware insertion of adaptive control algorithm approaches. An alternative is required for compact implementation of such functionality to withstand the harsh environment

  17. Digital BPM Systems for Hadron Accelerators

    CERN Document Server

    Belleman, J; Kasprowicz, G; Raich, U

    2009-01-01

    The CERN Proton Synchrotron has been fitted with a new trajectory measurement system (TMS). Analogue signals from forty beam position monitors are digitized at 125MS/s, and then further treated entirely in the digital domain to derive the positions of all individual particle bunches on the fly. Large FPGAs handle all digital processing. The system fits in fourteen plug-in modules distributed over three half-width cPCI crates. Data are stored in circular buffers of large enough size to keep a fewseconds-worth of position data. Multiple clients can then request selected portions of the data, possibly representing many thousands of consecutive turns, for display on operator consoles. The system uses digital phase-locked loops to derive its beamlocked timing reference. Programmable state machines, driven by accelerator timing pulses and information from the accelerator control system, direct the order of operations. The cPCI crates are connected to a standard Linux computer by means of a private Gigabit Ethernet ...

  18. Digital I and C system upgrade integration technique

    International Nuclear Information System (INIS)

    Huang, H. W.; Shih, C.; Wang, J. R.; Huang, K. C.

    2012-01-01

    This work developed an integration technique for digital I and C system upgrade, the utility can replace the I and C systems step by step systematically by this method. Inst. of Nuclear Energy Research (INER) developed a digital Instrumentation and Control (I and C) replacement integration technique on the basis of requirement of the three existing nuclear power plants (NPPs), which are Chin-Shan (CS) NPP, Kuo-Sheng (KS) NPP, and Maanshan (MS) NPP, in Taiwan, and also developed the related Critical Digital Review (CDR) Procedure. The digital I and C replacement integration technique includes: (I) Establishment of Nuclear Power Plant Digital Replacement Integration Guideline, (2) Preliminary Investigation on I and C System Digitalization, (3) Evaluation on I and C System Digitalization, and (4) Establishment of I and C System Digitalization Architectures. These works can be a reference for performing I and C system digital replacement integration of the three existing NPPs of Taiwan Power Company (TPC). A CDR is the review for a critical system digital I and C replacement. The major reference of this procedure is EPRI TR- 1011710 (2005) 'Handbook for Evaluating Critical Digital Equipment and Systems' which was published by the Electric Power Research Inst. (EPRI). With this document, INER developed a TPC-specific CDR procedure. Currently, CDR becomes one of the policies for digital I and C replacement in TPC. The contents of this CDR procedure include: Scope, Responsibility, Operation Procedure, Operation Flow Chart, CDR review items. The CDR review items include the comparison of the design change, Software Verification and Validation (SVandV), Failure Mode and Effects Analysis (FMEA), Evaluation of Diversity and Defense-in-depth (D3), Evaluation of Watchdog Timer, Evaluation of Electromagnetic Compatibility (EMC), Evaluation of Grounding for System/Component, Seismic Evaluation, Witness and Inspection, Lessons Learnt from the Digital I and C Failure Events. A

  19. Digital I and C system upgrade integration technique

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H. W. [Inst. of Nuclear Energy Research (INER), No. 1000, Wenhua Road, Chiaan Village, Longtan Township, Taoyuan County, 32546, Taiwan (China); Shih, C. [Inst. of Nuclear Engineering and Science, National Tsing Hua Univ., 101, Sec. 2, Kuang Fu Rd, Hsinchu, Taiwan (China); Wang, J. R. [Inst. of Nuclear Energy Research (INER), No. 1000, Wenhua Road, Chiaan Village, Longtan Township, Taoyuan County, 32546, Taiwan (China); Huang, K. C. [Inst. of Nuclear Engineering and Science, National Tsing Hua Univ., 101, Sec. 2, Kuang Fu Rd, Hsinchu, Taiwan (China)

    2012-07-01

    This work developed an integration technique for digital I and C system upgrade, the utility can replace the I and C systems step by step systematically by this method. Inst. of Nuclear Energy Research (INER) developed a digital Instrumentation and Control (I and C) replacement integration technique on the basis of requirement of the three existing nuclear power plants (NPPs), which are Chin-Shan (CS) NPP, Kuo-Sheng (KS) NPP, and Maanshan (MS) NPP, in Taiwan, and also developed the related Critical Digital Review (CDR) Procedure. The digital I and C replacement integration technique includes: (I) Establishment of Nuclear Power Plant Digital Replacement Integration Guideline, (2) Preliminary Investigation on I and C System Digitalization, (3) Evaluation on I and C System Digitalization, and (4) Establishment of I and C System Digitalization Architectures. These works can be a reference for performing I and C system digital replacement integration of the three existing NPPs of Taiwan Power Company (TPC). A CDR is the review for a critical system digital I and C replacement. The major reference of this procedure is EPRI TR- 1011710 (2005) 'Handbook for Evaluating Critical Digital Equipment and Systems' which was published by the Electric Power Research Inst. (EPRI). With this document, INER developed a TPC-specific CDR procedure. Currently, CDR becomes one of the policies for digital I and C replacement in TPC. The contents of this CDR procedure include: Scope, Responsibility, Operation Procedure, Operation Flow Chart, CDR review items. The CDR review items include the comparison of the design change, Software Verification and Validation (SVandV), Failure Mode and Effects Analysis (FMEA), Evaluation of Diversity and Defense-in-depth (D3), Evaluation of Watchdog Timer, Evaluation of Electromagnetic Compatibility (EMC), Evaluation of Grounding for System/Component, Seismic Evaluation, Witness and Inspection, Lessons Learnt from the Digital I and C Failure

  20. Development of digital device based work verification system for cooperation between main control room operators and field workers in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Min, E-mail: jewellee@kaeri.re.kr [Korea Atomic Energy Research Institute, 305-353, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Lee, Hyun Chul, E-mail: leehc@kaeri.re.kr [Korea Atomic Energy Research Institute, 305-353, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Ha, Jun Su, E-mail: junsu.ha@kustar.ac.ae [Department of Nuclear Engineering, Khalifa University of Science Technology and Research, Abu Dhabi P.O. Box 127788 (United Arab Emirates); Seong, Poong Hyun, E-mail: phseong@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2016-10-15

    Highlights: • A digital device-based work verification and cooperation support system was developed. • Requirements were derived by interviewing field operators having experiences with mobile-based work support systems. • The usability of the proposed system was validated by conducting questionnaire surveys. • The proposed system will be useful if the manual or the set of guidelines is well constructed. - Abstract: Digital technologies have been applied in the nuclear field to check task results, monitor events and accidents, and transmit/receive data. The results of using digital devices have proven that these devices can provide high accuracy and convenience for workers, allowing them to obtain obvious positive effects by reducing their workloads. In this study, as one step forward, a digital device-based cooperation support system, the nuclear cooperation support and mobile documentation system (Nu-COSMOS), is proposed to support communication between main control room (MCR) operators and field workers by verifying field workers’ work results in nuclear power plants (NPPs). The proposed system consists of a mobile based information storage system to support field workers by providing various functions to make workers more trusted by MCR operators; also to improve the efficiency of meeting, and a large screen based information sharing system supports meetings by allowing both sides to share one medium. The usability of this system was estimated by interviewing field operators working in nuclear power plants and experts who have experience working as operators. A survey to estimate the usability of the suggested system and the suitability of the functions of the system for field working was conducted for 35 subjects who have experience in field works or with support system development-related research. The usability test was conducted using the system usability scale (SUS), which is widely used in industrial usability evaluation. Using questionnaires

  1. Development of digital device based work verification system for cooperation between main control room operators and field workers in nuclear power plants

    International Nuclear Information System (INIS)

    Lee, Seung Min; Lee, Hyun Chul; Ha, Jun Su; Seong, Poong Hyun

    2016-01-01

    Highlights: • A digital device-based work verification and cooperation support system was developed. • Requirements were derived by interviewing field operators having experiences with mobile-based work support systems. • The usability of the proposed system was validated by conducting questionnaire surveys. • The proposed system will be useful if the manual or the set of guidelines is well constructed. - Abstract: Digital technologies have been applied in the nuclear field to check task results, monitor events and accidents, and transmit/receive data. The results of using digital devices have proven that these devices can provide high accuracy and convenience for workers, allowing them to obtain obvious positive effects by reducing their workloads. In this study, as one step forward, a digital device-based cooperation support system, the nuclear cooperation support and mobile documentation system (Nu-COSMOS), is proposed to support communication between main control room (MCR) operators and field workers by verifying field workers’ work results in nuclear power plants (NPPs). The proposed system consists of a mobile based information storage system to support field workers by providing various functions to make workers more trusted by MCR operators; also to improve the efficiency of meeting, and a large screen based information sharing system supports meetings by allowing both sides to share one medium. The usability of this system was estimated by interviewing field operators working in nuclear power plants and experts who have experience working as operators. A survey to estimate the usability of the suggested system and the suitability of the functions of the system for field working was conducted for 35 subjects who have experience in field works or with support system development-related research. The usability test was conducted using the system usability scale (SUS), which is widely used in industrial usability evaluation. Using questionnaires

  2. Low cost highly available digital control computer

    International Nuclear Information System (INIS)

    Silvers, M.W.

    1986-01-01

    When designing digital controllers for critical plant control it is important to provide several features. Among these are reliability, availability, maintainability, environmental protection, and low cost. An examination of several applications has lead to a design that can be produced for approximately $20,000 (1000 control points). This design is compatible with modern concepts in distributed and hierarchical control. The canonical controller element is a dual-redundant self-checking computer that communicates with a cross-strapped, electrically isolated input/output system. The input/output subsystem comprises multiple intelligent input/output cards. These cards accept commands from the primary processor which are validated, executed, and acknowledged. Each card may be hot replaced to facilitate sparing. The implementation of the dual-redundant computer architecture is discussed. Called the FS-86, this computer can be used for a variety of applications. It has most recently found application in the upgrade of San Francisco's Bay Area Rapid Transit (BART) train control currently in progress and has been proposed for feedwater control in a boiling water reactor

  3. Bus-oriented digital control techniques in nuclear power plants

    International Nuclear Information System (INIS)

    Salm, M.

    1987-01-01

    The author states the conservative principles which govern the authorization procedures for nuclear reactor control systems. Using the example of a feedwater supply regulator, employing a digital, bus-oriented control system, he describes how the stigma attached to the word nuclear can be alleviated. (G.T.H.)

  4. A state-of-the-art report on software operation structure of the digital control computer system

    International Nuclear Information System (INIS)

    Kim, Bong Kee; Lee, Kyung Hoh; Joo, Jae Yoon; Jang, Yung Woo; Shin, Hyun Kook

    1994-06-01

    CANDU Nuclear Power Plants including Wolsong 1 and 2/3/4 are controlled by a real-time plant control computer system. This report was written to provide an overview on the station control computer software which belongs to one of the most advanced real-time computing application area, along with the Fuel Handling Machine design concepts. The combination of well designed control computer and Fuel Handling Machine allow changing fuel bundles while the plant is in operation. Design methodologies and software structure are discussed along with the interface between the two systems. 29 figs., 2 tabs., 20 refs. (Author)

  5. A state-of-the-art report on software operation structure of the digital control computer system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bong Kee; Lee, Kyung Hoh; Joo, Jae Yoon; Jang, Yung Woo; Shin, Hyun Kook [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-06-01

    CANDU Nuclear Power Plants including Wolsong 1 and 2/3/4 are controlled by a real-time plant control computer system. This report was written to provide an overview on the station control computer software which belongs to one of the most advanced real-time computing application area, along with the Fuel Handling Machine design concepts. The combination of well designed control computer and Fuel Handling Machine allow changing fuel bundles while the plant is in operation. Design methodologies and software structure are discussed along with the interface between the two systems. 29 figs., 2 tabs., 20 refs. (Author).

  6. Development and applications of a multi-purpose digital controller with a System-on-Chip FPGA for accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Kurimoto, Yoshinori, E-mail: kurimoto@post.j-parc.jp [High Energy Accelerator Research Organization (KEK), Ibaraki 319-1195 (Japan); Nakamura, Keigo [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)

    2016-12-21

    J-PARC Main Ring (MR) is a high intensity proton synchrotron which accelerates protons from 3 GeV to 30 GeV. It has operated at a beam intensity of 390 kW and an upgrade toward the megawatt rating is scheduled. For higher beam intensity, some of the accelerator components require more intelligent and complicated functions. To consolidate such functions among various components, we developed multi-purpose digital boards using a System-on-Chip Field-Programmable Gated Array (SoC FPGA). In this paper, we describe the details of our developed boards as well as their possible applications. As an application of the boards, we have successfully performed the measurement of the betatron amplitude function during beam acceleration in J-PARC MR. The experimental setup and results of the measurement are also described in detail.

  7. Application of MATLAB in testing digital power supply controllers

    International Nuclear Information System (INIS)

    Ke Xinhua; Chinese Academy of Sciences, Beijing; Lu Songlin; Shen Tianjian

    2008-01-01

    Based on introducing MATLAB SISOTOOL in MATLAB control box and the magnet power supply system in detail, this paper presented the application of MATLAB SISOTOOL in Testing Digital Power Supply controllers. This control tool should be popularized because of its characteristics of convenience and easy-to-use. (authors)

  8. MAS2-8 radar and digital control unit

    Science.gov (United States)

    Oberg, J. M.; Ulaby, F. T.

    1974-01-01

    The design of the MAS 2-8 (2 to 8 GHz microwave-active spectrometer), a ground-based sensor system, is presented. A major modification in 1974 to the MAS 2-8, that of a control subsystem to automate the data-taking operation, is the prime focus. The digital control unit automatically changes all system parameters except FM rate and records the return signal on paper tape. The overall system operation and a detailed discussion of the design and operation of the digital control unit are presented.

  9. Hardware replacements and software tools for digital control computers

    International Nuclear Information System (INIS)

    Walker, R.A.P.; Wang, B-C.; Fung, J.

    1996-01-01

    Technological obsolescence is an on-going challenge for all computer use. By design, and to some extent good fortune, AECL has had a good track record with respect to the march of obsolescence in CANDU digital control computer technology. Recognizing obsolescence as a fact of life, AECL has undertaken a program of supporting the digital control technology of existing CANDU plants. Other AECL groups are developing complete replacement systems for the digital control computers, and more advanced systems for the digital control computers of the future CANDU reactors. This paper presents the results of the efforts of AECL's DCC service support group to replace obsolete digital control computer and related components and to provide friendlier software technology related to the maintenance and use of digital control computers in CANDU. These efforts are expected to extend the current lifespan of existing digital control computers through their mandated life. This group applied two simple rules; the product, whether new or replacement should have a generic basis, and the products should be applicable to both existing CANDU plants and to 'repeat' plant designs built using current design guidelines. While some exceptions do apply, the rules have been met. The generic requirement dictates that the product should not be dependent on any brand technology, and should back-fit to and interface with any such technology which remains in the control design. The application requirement dictates that the product should have universal use and be user friendly to the greatest extent possible. Furthermore, both requirements were designed to anticipate user involvement, modifications and alternate user defined applications. The replacements for hardware components such as paper tape reader/punch, moving arm disk, contact scanner and Ramtek are discussed. The development of these hardware replacements coincide with the development of a gateway system for selected CANDU digital control

  10. Digital system design with VHDL

    International Nuclear Information System (INIS)

    Kang, Jin Gu; Lee, Da Young; Song, Je Chel

    2000-09-01

    This book is comprised of eleven chapters, which are review of basic logic design including combinational logic circuit, KARNAUGH MAPS, Hazard of combinational circuit, Melay order circuit design and synchronous design, introduction of VHDL like VHDL module of Multiplexer and VHDL Function, design with PLD for program, circuit design for arithmetical operation, digital design using SM chart, PGA and CPLD design, Floating-point calculation, extra issues on VHDL, VHDL module for memory and bus,design for hardware test and a testing and examples for design such as UART design and M68HC05 micro controller.

  11. Design, assembly, and initial use of a digital system for the closed-loop control of a nuclear research reactor

    International Nuclear Information System (INIS)

    Kwok, K.S.; Bernard, J.A.; Lanning, D.D.

    1991-01-01

    In this paper the design, implementation, and initial testing of a multiple-computer/single-task system for the closed-loop control of a nuclear research reactor is described. A major advantage of the multiple-computer approach is that generic safety-related software that remains invariant can be separated from the control law software that is updated as plant procedures change. This facilitates software validation. Also, this approach allows both real-time operation and high numerical throughput. System compatibility was achieved through design of a special passive back plane which enabled the otherwise incompatible components to be operated in an integrated system. This multiple-computer system, which was designated as the Advanced Control Computer System (ACCS), has been installed on the 5-MWt MIT Research Reactor. In addition to a description of both the system and its associated hardware and software interfaces, experimental results are presented from its initial trials

  12. Computationally efficient methods for digital control

    NARCIS (Netherlands)

    Guerreiro Tome Antunes, D.J.; Hespanha, J.P.; Silvestre, C.J.; Kataria, N.; Brewer, F.

    2008-01-01

    The problem of designing a digital controller is considered with the novelty of explicitly taking into account the computation cost of the controller implementation. A class of controller emulation methods inspired by numerical analysis is proposed. Through various examples it is shown that these

  13. Fine Output Voltage Control Method considering Time-Delay of Digital Inverter System for X-ray Computed Tomography

    Science.gov (United States)

    Shibata, Junji; Kaneko, Kazuhide; Ohishi, Kiyoshi; Ando, Itaru; Ogawa, Mina; Takano, Hiroshi

    This paper proposes a new output voltage control for an inverter system, which has time-delay and nonlinear load. In the next generation X-ray computed tomography of a medical device (X-ray CT) that uses the contactless power transfer method, the feedback signal often contains time-delay due to AD/DA conversion and error detection/correction time. When the PID controller of the inverter system is received the adverse effects of the time-delay, the controller often has an overshoot and a oscillated response. In order to overcome this problem, this paper proposes a compensation method based on the Smith predictor for an inverter system having a time-delay and the nonlinear loads which are the diode bridge rectifier and X-ray tube. The proposed compensation method consists of the hybrid Smith predictor system based on an equivalent analog circuit and DSP. The experimental results confirm the validity of the proposed system.

  14. Systems and methods for self-synchronized digital sampling

    Science.gov (United States)

    Samson, Jr., John R. (Inventor)

    2008-01-01

    Systems and methods for self-synchronized data sampling are provided. In one embodiment, a system for capturing synchronous data samples is provided. The system includes an analog to digital converter adapted to capture signals from one or more sensors and convert the signals into a stream of digital data samples at a sampling frequency determined by a sampling control signal; and a synchronizer coupled to the analog to digital converter and adapted to receive a rotational frequency signal from a rotating machine, wherein the synchronizer is further adapted to generate the sampling control signal, and wherein the sampling control signal is based on the rotational frequency signal.

  15. A dual-mode generalized likelihood ratio approach to self-reorganizing digital flight control system design

    Science.gov (United States)

    1976-01-01

    Analytic techniques have been developed for detecting and identifying abrupt changes in dynamic systems. The GLR technique monitors the output of the Kalman filter and searches for the time that the failure occured, thus allowing it to be sensitive to new data and consequently increasing the chances for fast system recovery following detection of a failure. All failure detections are based on functional redundancy. Performance tests of the F-8 aircraft flight control system and computerized modelling of the technique are presented.

  16. Compact lidar system using laser diode, binary continuous wave power modulation, and an avalanche photodiode-based receiver controlled by a digital signal processor

    Science.gov (United States)

    Ardanuy, Antoni; Comerón, Adolfo

    2018-04-01

    We analyze the practical limits of a lidar system based on the use of a laser diode, random binary continuous wave power modulation, and an avalanche photodiode (APD)-based photereceiver, combined with the control and computing power of the digital signal processors (DSP) currently available. The target is to design a compact portable lidar system made all in semiconductor technology, with a low-power demand and an easy configuration of the system, allowing change in some of its features through software. Unlike many prior works, we emphasize the use of APDs instead of photomultiplier tubes to detect the return signal and the application of the system to measure not only hard targets, but also medium-range aerosols and clouds. We have developed an experimental prototype to evaluate the behavior of the system under different environmental conditions. Experimental results provided by the prototype are presented and discussed.

  17. Control and automation systems

    International Nuclear Information System (INIS)

    Schmidt, R.; Zillich, H.

    1986-01-01

    A survey is given of the development of control and automation systems for energy uses. General remarks about control and automation schemes are followed by a description of modern process control systems along with process control processes as such. After discussing the particular process control requirements of nuclear power plants the paper deals with the reliability and availability of process control systems and refers to computerized simulation processes. The subsequent paragraphs are dedicated to descriptions of the operating floor, ergonomic conditions, existing systems, flue gas desulfurization systems, the electromagnetic influences on digital circuits as well as of light wave uses. (HAG) [de

  18. A real-time digital control, data acquisition and analysis system for the DIII-D multipulse Thomson scattering diagnostic

    International Nuclear Information System (INIS)

    Greenfield, C.M.; Campbell, G.L.; Carlstrom, T.N.; DeBoo, J.C.; Hsieh, C.-L.; Snider, R.T.; Trost, P.K.

    1990-10-01

    A VME-based real-time computer systems for laser control, data acquisition and analysis for the DIII-D multipulse Thomson scattering diagnostic is described. The laser control task requires precise timing of up to 8 Nd:YAG lasers, each with an average firing rate of 20 Hz. A cpu module in real-time multiprocessing computer system will operate the lasers with evenly staggered laser pulses or in a ''burst mode'', where all available (fully charged) lasers can be fired at 50--100 μsec intervals upon receipt of an external event trigger signal. One of more cpu modules, along with a LeCroy FERA (Fast Encoding and Readout ADC) system, will perform real-time data acquisition and analysis. Partial electron temperature and density profiles will be available for plasma feedback control within 1 msec following each laser pulse. The VME-based computer system consists of 2 or more target processor modules (25 MHz Motorola 68030) running the VMEexec real-time operating system connected to a Unix based host system (also a 68030). All real-time software is fully interrupt driven to maximize system efficiency. Operator interaction and (non real-time) data analysis takes place on a MicroVAX 3400 connected via DECnet. 17 refs., 1 fig

  19. Real-time digital control, data acquisition, and analysis system for the DIII-D multipulse Thomson scattering diagnostic

    International Nuclear Information System (INIS)

    Greenfield, C.M.; Campbell, G.L.; Carlstrom, T.N.; DeBoo, J.C.; Hsieh, C.; Snider, R.T.; Trost, P.K.

    1990-01-01

    A VME-based real-time computer system for laser control, data acquisition, and analysis for the DIII-D multipulse Thomson scattering diagnostic is described. The laser control task requires precise timing of up to eight Nd:YAG lasers, each with an average firing rate of 20 Hz. A cpu module in a real-time multiprocessing computer system will operate the lasers with evenly staggered laser pulses or in a ''burst mode,'' where all available (fully charged) lasers can be fired at 50--100 μs intervals upon receipt of an external event trigger signal. One or more cpu modules, along with a LeCroy FERA (fast encoding and readout ADC) system, will perform real-time data acquisition and analysis. Partial electron temperature and density profiles will be available for plasma feedback control within 1 ms following each laser pulse. The VME-based computer system consists of two or more target processor modules (25 MHz Motorola 68030) running the VMEexec real-time operating system connected to a Unix-based host system (also a 68030). All real-time software is fully interrupt driven to maximize system efficiency. Operator interaction and (non-real-time) data analysis takes place on a MicroVAX 3400 connected via DECnet

  20. Auxiliary controller for time-to-digital converter module readout

    International Nuclear Information System (INIS)

    Ermolin, Yu.V.

    1992-01-01

    The KD-225 auxiliary controller for time-to-digital converter module readout in the SUMMA crate is described. After readout and preliminary processing the data are written in the P-140 buffer memory module. The controller is used in the FODS-2 experimental setup data acquisition system. 12 refs.; 1 fig

  1. Development and application of all-digital monitoring system

    International Nuclear Information System (INIS)

    Xu Tao; Li Jing; Wang Wei

    2014-01-01

    All digital control system has developed into a mainstream means of monitoring, and achieved information, intelligence, and networking. All-digital control system is characterized by clear image, large transport stream, so the higher the data storage and network bandwidth should be required. Existing analog surveillance system architecture, hardware and software configuration can not meet the requirements of all-digital monitoring system, so how to solve the original analog surveillance system is gradually transformed into fully digital monitoring system, to avoid incompatibility issues in surveillance monitoring system upgrade become a research project. This paper describes the advantages and future direction of megapixels camera and proposes key technologies to solve the resolution and frame rate with the actual project requirements, achieves a core technology of megapixels video surveillance system, and proposes solutions for the actual renovation project problems. (authors)

  2. Transceiver and system design for digital communications

    CERN Document Server

    Bullock, Scott

    2009-01-01

    Now in a 3rd edition, this successful book provides an intuitive approach to transceiver design, allowing a broad spectrum of readers to understand the topics clearly. It covers a wide range of data link communication design techniques, including link budgets, dynamic range and system analysis of receivers and transmitters used in data link communications, digital modulation and demodulation techniques of phase-shift keyed and frequency hopped spread spectrum systems using phase diagrams, multipath, gain control, an intuitive approach to probability, jamming reduction method using various adap

  3. Digital Signal Processing and Control for the Study of Gene Networks

    Science.gov (United States)

    Shin, Yong-Jun

    2016-04-01

    Thanks to the digital revolution, digital signal processing and control has been widely used in many areas of science and engineering today. It provides practical and powerful tools to model, simulate, analyze, design, measure, and control complex and dynamic systems such as robots and aircrafts. Gene networks are also complex dynamic systems which can be studied via digital signal processing and control. Unlike conventional computational methods, this approach is capable of not only modeling but also controlling gene networks since the experimental environment is mostly digital today. The overall aim of this article is to introduce digital signal processing and control as a useful tool for the study of gene networks.

  4. Portable digital electronic radiography system

    International Nuclear Information System (INIS)

    Sawicka, B.D.

    1995-01-01

    Radiography is a standard nondestructive technique in the industrial testing of materials and components. It is routinely used during the construction, maintenance and repair of nuclear plants. Traditionally, radiography is performed using photographic film (film radiography, FR). Recent developments in solid-state area imaging radiation detectors, miniature electronics and computer software/hardware techniques have brought electronic alternatives to FR. In recent years various electronic radiography (ER) techniques have served as alternatives to FR, these proved beneficial in some applications. While originally developed to provide real time imaging, ER may offer other advantages over FR, depending on the application. Work was undertaken at CRL to review progress in ER techniques and evaluate the possibility of constructing a portable DER (digital electronic radiography) system, for the inspection of power plant components. A suitable DER technique has been developed and a proof of principle portable system constructed. As this paper demonstrates, a properly designed ER system can be small and compact, while providing radiographic examination with acceptable image quality and the benefits of ER imaging. The CRL DER system can operate with radioactive sources typical of FR. While it does not replace FR, our DER system is expected to be beneficial in specific applications for Candu maintenance, reducing cost, labour and time. Practical, cost saving applications of this system are expected to include valve monitoring and foreign object location during maintenance at Candu reactors

  5. CEBAF NEW DIGITAL LLRF SYSTEM EXTENDED FUNCTIONALITY

    International Nuclear Information System (INIS)

    T. Allison; K. Davis; H. Dong; C. Hovater; L. King; J. Musson; T. Plawski

    2007-01-01

    The new digital LLRF system for the CEBAF 12GeV accelerator will perform a variety of tasks, beyond field control [1]. In this paper we present the superconducting cavity resonance control system designed to minimize RF power during gradient ramp and to minimize RF power during steady state operation. Based on the calculated detuning angle, which represents the difference between reference and cavity resonance frequency, the cavity length will be adjusted with a mechanical tuner. The tuner has two mechanical driving devices, a stepper motor and a piezo-tuner, to yield a combination of coarse and fine control. Although LLRF piezo processing speed can achieve 10 kHz bandwidth, only 10 Hz speed is needed for 12 GeV upgrade. There will be a number of additional functions within the LLRF system; heater controls to maintain cryomodule's heat load balance, ceramic window temperature monitoring, waveguide vacuum interlocks, ARC detector interlock and quench detection. The additional functions will be divided between the digital board, incorporating an Altera FPGA and an embedded EPICS IOC. This paper will also address hardware evolution and test results performed with different SC cavities

  6. Design of coordinated controller in nuclear power plant based on digital instrument and control technology

    International Nuclear Information System (INIS)

    Cheng Shouyu; Peng Minjun; Liu Xinkai; Zhao Qiang; Deng Xiangxin

    2014-01-01

    Nuclear power plant (NPP) is a multi-input and multi-output, no-linear and time-varying complex system. The conventional PID controller is usually used in NPP control system which is based on analog instrument. The system parameters are easy to overshoot and the response time is longer in the control mode of the conventional PID. In order to improve this condition, a new coordinated control strategy which is based on expert system and the original controllers in the digital instrument and control technology was presented. In order to verify and validate it, the proposed coordinated control technology was tested by the full-scope real-time simulation system. The results prove that using digital instrument and control technology to achieve coordinated controller is feasible, the coordinated controller can effectively improve the dynamic operating characteristics of the system, and the coordinated controller is superior to the conventional PID controller in control performance. (authors)

  7. A digital controller for the Omega West Reactor

    International Nuclear Information System (INIS)

    Minor, M.M.; Kaufman, M.D.; Smith, T.W.

    1992-05-01

    A new nuclear reactor control system for the Omega West Reactor (OWR) has been designed to replace the aging and hard to maintain controller presently installed. The controller uses single board computers, digital and analog input and output modules, and stepping motor indexers installed on a standard bus (VME bus). The eight poison control rod drive motors are replaced with stepping motors. The control algorithm for the OWR was not changed in order to expedite approval for installation. This report presents the results of the development of the new control system. Included in the report are copies of some of the software that drives the new controller

  8. Manufacture of Platform Prototype for Digital Safety System

    International Nuclear Information System (INIS)

    Lee, S. Y.; Kim, J. S.; Kim, J. M.

    2010-01-01

    Unit controller is a basic unit of digital safety system platform prototype. The typical unit controller is comprised of CPB(CPU board), CMB(communication board), AIB(Analog input board), AOB(Analog output board), CIB(contact input board), COB(contact output board), and a subrack. It is developed according to H/W development procedure and S/W development life cycle. A digital safety system(for example, plant protection system) is the assemblies of unit controllers. CPB performs the function of each system. DSP(digital signal processor) is built in CPB. CMB is responsible for communication between unit controllers. NSD(Network Switching Device) exchanges data between the unit controllers. Each unit controller of the platform are connected to NSD through CMB. Reliability analyses on unit controller and NSD are performed. These reliability data are used as input of technical validation

  9. Market and Labour Control in Digital Capitalism

    Directory of Open Access Journals (Sweden)

    Philipp Staab

    2016-11-01

    Full Text Available Theorists of post capitalism have recently argued for a more or less inevitable end to capitalism. They assume that private accumulation is systematically blocked by the inability of capitalist corporations to create revenues by setting prices as they lose control over the reproduction of their commodities and that in this process, capitalist labour will eventually disappear. Drawing on a case study of Amazon and thoughts on the policies of other leading digital corporations, we challenge these assumptions. Key corporate players of digitization are trying to become powerful monopolies and have partly succeeded in doing so, using the network effects and scaling opportunities of digital goods and building socio-technical ecosystems. These strategies have led to the development of in part isomorphic structures, hence creating a situation of oligopolistic market competition. We draw on basic assumptions of monopoly capital theory to argue that in this situation labour process rationalization becomes key to the corporation’s competitive strategies. We see the expansion of digital control and the organizational structures applied by key corporate players of the digital economy as evidence for the expansion of capitalist labour, not its reduction.

  10. Using a digital signal processor as a data stream controller for digital subtraction angiography

    International Nuclear Information System (INIS)

    Meng, J.D.; Katz, J.E.

    1991-10-01

    High speed, flexibility, and good arithmetic abilities make digital signal processors (DSP) a good choice as input/output controllers for real time applications. The DSP can be made to pre-process data in real time to reduce data volume, to open early windows on what is being acquired and to implement local servo loops. We present an example of a DSP as an input/output controller for a digital subtraction angiographic imaging system. The DSP pre-processes the raw data, reducing data volume by a factor of two, and is potentially capable of producing real-time subtracted images for immediate display

  11. Adoption of digital safety protection system in Japan

    International Nuclear Information System (INIS)

    Ogiso, Z.

    1998-01-01

    The application of micro-processor-based digital controllers has been widely propagated among various industries in recent years. While in the nuclear power plant industry, the application of them has also been expanding gradually starting from non-safety related systems, taking advantage of their reliability and maintainability over the conventional analog devices. Based on the careful study of the feasibility of digital controllers to the safety protection system, the Tokyo Electric Power Company proposed on May 1989 the adoption of digital controllers to the safety protection system in the Application for Permission of Establishment of Kashiwazaki-Kariwa units 6 and 7 (ABWR-1350Mwe each). MITI, Ministry of International Trade and Industry, the Japanese regulatory body for electric power generating facilities, had approved this application after careful review. This paper describes a series of supporting activities leading to the MITI's approval of the digital safety protection system and the MITI's licensing activities. (author)

  12. Prototype of time digitizing system for BESⅢ endcap TOF upgrade

    International Nuclear Information System (INIS)

    Cao Ping; Sun Weijia; Fan Huanhuan; Wang Siyu; Liu Shubin; An Qi; Ji Xiaolu

    2014-01-01

    The prototype of a time digitizing system for the BESⅢ endcap TOF (ETOF) upgrade is introduced in this paper. The ETOF readout electronics has a distributed architecture. Hit signals from the multi-gap resistive plate chamber (MRPC) are signaled as LVDS by front-end electronics (FEE) and are then sent to the back-end time digitizing system via long shield differential twisted pair cables. The ETOF digitizing system consists of two VME crates, each of which contains modules for time digitization, clock, trigger, fast control, etc. The time digitizing module (TDIG) of this prototype can support up to 72 electrical channels for hit information measurement. The fast control (FCTL) module can operate in barrel or endcap mode. The barrel FCTL fans out fast control signals from the trigger system to the endcap FCTLs, merges data from the endcaps and then transfers to the trigger system. Without modifying the barrel TOF (BTOF) structure, this time digitizing architecture benefits from improved ETOF performance without degrading the BTOF performance. Lab experiments show that the time resolution of this digitizing system can be lower than 20 ps, and the data throughput to the DAQ can be about 92 Mbps. Beam experiments show that the total time resolution can be lower than 45 ps. (authors)

  13. Human factors issues in digital system design and implementation

    International Nuclear Information System (INIS)

    Galletti, Greg S.

    1998-01-01

    A goal of the U.S. Nuclear Regulatory Commission (NRC) is to ensure safety in the application of digital equipment upgrades to nuclear power plant control rooms and local control stations. One of the areas of specific interest is the integration of digital technology into existing analog control, display, and information systems and the implications of such integration for operators in regard to their use of this new equipment to safely operate the plant. This paper is a discussion of human performance issues related to the introduction of such digital equipment into operating nuclear power plants. (author)

  14. The impact research of control modes in steam turbine control system (digital electric hydraulic to the low-frequency oscillation of grid

    Directory of Open Access Journals (Sweden)

    Yanghai Li

    2016-01-01

    Full Text Available Through the analysis of the control theory for steam turbine, the transfer function of the steam turbine control modes in the parallel operation was obtained. The frequency domain analysis indicated that different control modes of turbine control system have different influence on the damping characteristics of the power system. The comparative analysis shows the direction and the degree of the influence under the different oscillation frequency range. This can provide the theory for the suppression of the low-frequency oscillation from turbine side and has a guiding significance for the stability of power system. The results of simulation tests are consistent with the theoretic analysis.

  15. Digital control for the Penn State Breazeale reactor

    International Nuclear Information System (INIS)

    Raiskums, G.A.

    1991-01-01

    Digital control has been an integral part of Canada deuterium uranium (CANDU) nuclear power reactor technology since the 1960s. Much of the high CANDU production reliability can be attributed to the fault-tolerant and flexible control algorithms achievable with digital control. Atomic Energy of Canada Limited (AECL) has now transported this technology to research reactors, using industrial-grade microcomputers to solve equipment aging and spares obsolescence problems so prevalent at older installations. The open architecture of the Intel 8086-based computers provides for wide availability and reasonably priced, quality hardware from numerous sources. AECL recently supplied the Pennsylvania State University Breazeale Reactor (PSBR) with a new console containing a digital control and monitoring system. The reactor safety system (RSS) was also replaced with hardwired relay logic and truly analog state-of-the-art wide range nuclear instrumentation supplied by AECL's subcontractor, Gamma-Metrics. Retaining analog hardware for the mandated RSS functions was key to minimizing licensing efforts and the extensive verification and validation that would be required for safety system software. This paper elaborates on the digital control and monitoring portion of the PSBR console replacement, with emphasis on the key system objectives

  16. Digital Voting Systems and Communication in Classroom Lectures

    DEFF Research Database (Denmark)

    Mathiasen, Helle

    2015-01-01

    Studies on the use of digital voting systems in large group teaching situations have often focused on the ”non-anonymity” and control and testing functions that the technology provides. There has also been some interest in how students might use their votes tactically to gain “credits”. By focusing...... on an empirical study of students’ experiences with digital voting systems in lectures at two Danish universities, this study considers the premises and the contexts surrounding this technology. It will also aim to show that for both instructors and students, digital voting systems are a much broader resource...... than simply a device for facilitating ”non-anonymity”, test, control and allocation of credits. The case studies showed, for instance, that digital voting systems can be conducive to a more open approach in which the systems are used as communication tools and teaching resources in situations where...

  17. Digital systems from logic gates to processors

    CERN Document Server

    Deschamps, Jean-Pierre; Terés, Lluís

    2017-01-01

    This textbook for a one-semester course in Digital Systems Design describes the basic methods used to develop “traditional” Digital Systems, based on the use of logic gates and flip flops, as well as more advanced techniques that enable the design of very large circuits, based on Hardware Description Languages and Synthesis tools. It was originally designed to accompany a MOOC (Massive Open Online Course) created at the Autonomous University of Barcelona (UAB), currently available on the Coursera platform. Readers will learn what a digital system is and how it can be developed, preparing them for steps toward other technical disciplines, such as Computer Architecture, Robotics, Bionics, Avionics and others. In particular, students will learn to design digital systems of medium complexity, describe digital systems using high level hardware description languages, and understand the operation of computers at their most basic level. All concepts introduced are reinforced by plentiful illustrations, examples, ...

  18. Development of Final Running Test System for Digital Systems

    International Nuclear Information System (INIS)

    Lee, Kwang-Dae; Lee, Eui-Jong; Lim, Hee-Taek; Kim, Min-Seok

    2016-01-01

    In nuclear industry, the newly designed systems to upgrade are qualified to meet IEEE standards and the regulatory guidelines for their functions, performance and reliability requirements. Failure Mode and Effect Analysis, Fault Tree Analysis, and Hazard Analysis have been used to improve the reliability of the control system. To ensure the completeness of the software, the verification and validation processes are carried out during the development process. In spite of the many efforts depending on the analysis and procedures, there are limitations to improve the reliability. The lessons learned from the currently installed system failures show the incompleteness of the final integration test. The current point-to-point and logic-to-logic separate test procedures manually performed by the engineers can cause some procedures missed and have effects on the critical functions. The design processes of the digital systems are met in accordance with the international standards and regulatory guidelines. The lessons learned from the failures of the running digital systems showed the limitations of the current verification and validation efforts. The various improvements and attempts have been considered including the expert review processes and the completeness of the test. In this paper, the Final Running Test Method evaluating the completeness of the digital system using the control patterns and the Test System Architecture are proposed

  19. Development of Final Running Test System for Digital Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kwang-Dae; Lee, Eui-Jong; Lim, Hee-Taek; Kim, Min-Seok [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    In nuclear industry, the newly designed systems to upgrade are qualified to meet IEEE standards and the regulatory guidelines for their functions, performance and reliability requirements. Failure Mode and Effect Analysis, Fault Tree Analysis, and Hazard Analysis have been used to improve the reliability of the control system. To ensure the completeness of the software, the verification and validation processes are carried out during the development process. In spite of the many efforts depending on the analysis and procedures, there are limitations to improve the reliability. The lessons learned from the currently installed system failures show the incompleteness of the final integration test. The current point-to-point and logic-to-logic separate test procedures manually performed by the engineers can cause some procedures missed and have effects on the critical functions. The design processes of the digital systems are met in accordance with the international standards and regulatory guidelines. The lessons learned from the failures of the running digital systems showed the limitations of the current verification and validation efforts. The various improvements and attempts have been considered including the expert review processes and the completeness of the test. In this paper, the Final Running Test Method evaluating the completeness of the digital system using the control patterns and the Test System Architecture are proposed.

  20. Digital Speed Cascade Control, using Scilab / Xcos Environment

    Directory of Open Access Journals (Sweden)

    Petru Chioncel

    2016-10-01

    Full Text Available This paper presents an application of digital cascade control implemented in Scilab / Xcos environment, using a P type regulator for the position adjustment circuit, a PI controller for the speed circuit adjustment; the current respectively moments control circuits are rendered by elements of PT1 type. On this basis the program is done in Scilab and the related signal block diagram implemented in Xcos; through simulation, the step response of the system is analyzed for different sampling times.

  1. Digital regulation of a phase controlled power converter

    International Nuclear Information System (INIS)

    Schultheiss, C.; Haque, T.

    1995-01-01

    The Relativistic Heavy Ion Collider, now in construction at Brookhaven National Laboratory, will use phase controlled power converters for the main dipole and quadrupole magnet strings. The rectifiers in these power supplies will be controlled by a digital regulator based on the TI 320C30 Digital Signal Processor (DSP). The DSP implements the current loop, the voltage loop, and a system to actively reduce the sub-harmonic ripple components. Digital firing circuits consisting of a phase locked lop and counters are used to fire the SCRs. Corrections for the sub-harmonic reduction are calculated by the DSP and stored in registers in the firing circuit. These corrections are added in hardware, to the over-all firing count provided by the DSP. the resultant count is compared to a reference counter to fire the SCRs. This combination of a digital control system and the digital firing circuits allows the correction of the sub-harmonics in a real-time sense. A prototype of the regulator has been constructed, and the preliminary testing indicates a sub-harmonic reduction of 60 dB

  2. Centralized digital computer control of a research nuclear reactor

    International Nuclear Information System (INIS)

    Crawford, K.C.

    1987-01-01

    A hardware and software design for the centralized control of a research nuclear reactor by a digital computer are presented, as well as an investigation of automatic-feedback control. Current reactor-control philosophies including redundancy, inherent safety in failure, and conservative-yet-operational scram initiation were used as the bases of the design. The control philosophies were applied to the power-monitoring system, the fuel-temperature monitoring system, the area-radiation monitoring system, and the overall system interaction. Unlike the single-function analog computers currently used to control research and commercial reactors, this system will be driven by a multifunction digital computer. Specifically, the system will perform control-rod movements to conform with operator requests, automatically log the required physical parameters during reactor operation, perform the required system tests, and monitor facility safety and security. Reactor power control is based on signals received from ion chambers located near the reactor core. Absorber-rod movements are made to control the rate of power increase or decrease during power changes and to control the power level during steady-state operation. Additionally, the system incorporates a rudimentary level of artificial intelligence

  3. Conversion of a servomanipulator from analog to digital control

    International Nuclear Information System (INIS)

    Killough, S.M.; Martin, H.L.; Hamel, W.R.

    1986-01-01

    Oak Ridge National Laboratory (ORNL) has developed expertise in computer control of force-reflecting master/slave servomanipulators as a result of research for the Consolidated Fuel Reprocessing Program. These computer control capabilities have been applied to a commercially available servomanipulator, the TeleOperator Systems SM-229. All of the servo drive and control circuitry has been replaced with commercially available digital controls and amplifiers, and a customer software - package has been developed at ORNL. This conversion to digital computer control resulted in significant improvements in force-reflection characteristics, ease of operation, diagnostic capabilities, indexing features, and potential increased reliability. The system will be used at the Tokamak Fusion Test Reactor at the Princeton Plasma Physics Laboratory (PPPL) for maintenance demonstrations

  4. Digital feed back control for radial beam position

    International Nuclear Information System (INIS)

    Mestha, L.K.

    1989-09-01

    In the development of wide spread large scale distributed digital control systems, there is a requirement to automate small processes like radial beam control which will not only improve the beam quality but will also add local intelligence. Hence use is made here of digital control principles for such applications. The work concerned with the radial beam control discussed in this report has been developed for ISIS at RAL. The structure of the report is hence inclined more towards the local hardware system. The general feed back loop techniques can also be implemented for other control purpose. For instance, the author has successfully tested similar techniques to minimise the RF cavity tuning error, where the improvement in performance could not be matched by the analogue loop. A description of the RF cavity tuning programme and the associated experimental results will be published as a local paper for ISIS division. (author)

  5. Software V ampersand V methods for digital plant protection system

    International Nuclear Information System (INIS)

    Kim, Hung-Jun; Han, Jai-Bok; Chun, Chong-Son; Kim, Sung; Kim, Kern-Joong.

    1997-01-01

    Careful thought must be given to software design in the development of digital based systems that play a critical role in the successful operation of nuclear power plants. To evaluate the software verification and validation methods as well as to verify its system performance capabilities for the upgrade instrumentation and control system in the Korean future nuclear power plants, the prototype Digital Plant, Protection System (DPPS) based on the Programmable Logic Controller (PLC) has been constructed. The system design description and features are briefly presented, and the software design and software verification and validation methods are focused. 6 refs., 2 figs

  6. Digital simulation of power electronic systems

    International Nuclear Information System (INIS)

    Mehring, P.; Jentsch, W.; John, G.; Kraemer, D.

    1981-01-01

    The following paper contains the final report on the NETSIM-Project. The purpose of this project is to develop a special digital simulation system, which could serve as a base for routine application of simulation in planning and development of power electronic systems. The project is realized in two steps. First a basic network analysis system is established. With this system the basic models and methods in treating power electronic networks could be probed. The resulting system is then integrated into a general digital simulation system for continous systems (CSSL-System). This integrated simulation system allows for convenient modeling and simulation of power electronic systems. (orig.) [de

  7. Digital-flight-control-system software written in automated-engineering-design language: A user's guide of verification and validation tools

    Science.gov (United States)

    Saito, Jim

    1987-01-01

    The user guide of verification and validation (V&V) tools for the Automated Engineering Design (AED) language is specifically written to update the information found in several documents pertaining to the automated verification of flight software tools. The intent is to provide, in one document, all the information necessary to adequately prepare a run to use the AED V&V tools. No attempt is made to discuss the FORTRAN V&V tools since they were not updated and are not currently active. Additionally, the current descriptions of the AED V&V tools are contained and provides information to augment the NASA TM 84276. The AED V&V tools are accessed from the digital flight control systems verification laboratory (DFCSVL) via a PDP-11/60 digital computer. The AED V&V tool interface handlers on the PDP-11/60 generate a Univac run stream which is transmitted to the Univac via a Remote Job Entry (RJE) link. Job execution takes place on the Univac 1100 and the job output is transmitted back to the DFCSVL and stored as a PDP-11/60 printfile.

  8. Digital Signal Processor System for AC Power Drivers

    Directory of Open Access Journals (Sweden)

    Ovidiu Neamtu

    2009-10-01

    Full Text Available DSP (Digital Signal Processor is the bestsolution for motor control systems to make possible thedevelopment of advanced motor drive systems. The motorcontrol processor calculates the required motor windingvoltage magnitude and frequency to operate the motor atthe desired speed. A PWM (Pulse Width Modulationcircuit controls the on and off duty cycle of the powerinverter switches to vary the magnitude of the motorvoltages.

  9. A multi-channel waveform digitizer system

    International Nuclear Information System (INIS)

    Bieser, F.; Muller, W.F.J.

    1990-01-01

    The authors report on the design and performance of a multichannel waveform digitizer system for use with the Multiple Sample Ionization Chamber (MUSIC) Detector at the Bevalac. 128 channels of 20 MHz Flash ADC plus 256 word deep memory are housed in a single crate. Digital thresholds and hit pattern logic facilitate zero suppression during readout which is performed over a standard VME bus

  10. Development of digital subtraction system DAR-1200

    International Nuclear Information System (INIS)

    Kawai, Masumi; Shimizu, Yasumitsu; Ozaki, Takeshi; Sawada, Hiroshi; Uzuyama, Kazuhiro; Nishioka, Hiroyuki

    1989-01-01

    Digital subtraction angiography (DSA) has been of widespread use clinically, and it has attracted considerable attention in angiographic examination today. The merits of Shimadzu high resolution digital subtraction system DAR-1200 are reported in this paper. Furthermore, the principle and clinical usefullness of a new method of DSA called the Peak-Hold DSA are explained especially in details. (author)

  11. Attitude Control of a Satellite by using Digital Signal Processing

    Directory of Open Access Journals (Sweden)

    Adirelle C. Santana

    2012-03-01

    Full Text Available This article has discussed the development of a three-axis attitude digital controller for an artificial satellite using a digital signal processor. The main motivation of this study is the attitude control system of the satellite Multi-Mission Platform, developed by the Brazilian National Institute for Space Research for application in different sort of missions. The controller design was based on the theory of the Linear Quadratic Gaussian Regulator, synthesized from the linearized model of the motion of the satellite, i.e., the kinematics and dynamics of attitude. The attitude actuators considered in this study are pairs of cold gas jets powered by a pulse width/pulse frequency modulator. In the first stage of the project development, a system controller for continuous time was studied with the aim of testing the adequacy of the adopted control. The next steps had included an analysis of discretization techniques, the setting time of sampling rate, and the testing of the digital version of the Linear Quadratic Gaussian Regulator controller in the MATLAB/SIMULINK. To fulfill the study, the controller was implemented in a digital signal processor, specifically the Blackfin BF537 from Analog Devices, along with the pulse width/pulse frequency modulator. The validation tests used a scheme of co-simulation, where the model of the satellite was simulated in MATLAB/SIMULINK, while the controller and modulator were processed in the digital signal processor with a tool called Processor-In-the-Loop, which acted as a data communication link between both environments.function and required time to achieve a given mission accuracy are determined, and results are provided as illustration.

  12. Digital image information systems in radiology

    International Nuclear Information System (INIS)

    Greinacher, C.F.C.; Luetke, B.; Seufert, G.

    1987-01-01

    About 25% of all patient examinations are performed digitally in a today's radiological department. A computerized system is described that supports generation, transport, interpretation and archiving of digital radiological images (Picture Archiving and Communication System PACS). The technical features concerning image communication via local area networks, image storage on magnetic and optical media and digital workstations for image display and manipulation are described. A structured system architecture is introduced. It allows flexible adaption to individual organizations and minimizes the requirements of the communication network. (orig.) [de

  13. Abnormal condition and events analysis for instrumentation and control systems. Volume 1: Methodology for nuclear power plant digital upgrades. Final report

    International Nuclear Information System (INIS)

    McKemy, S.; Marcelli, M.; Boehmer, N.; Crandall, D.

    1996-01-01

    The ACES project was initiated to identify a cost-effective methodology for addressing abnormal conditions and events (ACES) in digital upgrades to nuclear power plant systems, as introduced by IEEE Standard 7-4.3.2-1993. Several methodologies and techniques currently in use in the defense, aerospace, and other communities for the assurance of digital safety systems were surveyed, and although several were shown to possess desirable qualities, non sufficiently met the needs of the nuclear power industry. This report describes a tailorable methodology for performing ACES analysis that is based on the more desirable aspects of the reviewed methodologies and techniques. The methodology is applicable to both safety- and non-safety-grade systems, addresses hardware, software, and system-level concerns, and can be applied in either a lifecycle or post-design timeframe. Employing this methodology for safety systems should facilitate the digital upgrade licensing process

  14. Dosimetric quality control of treatment planning systems in external radiation therapy using Digital Test Objects calculated by PENELOPE Monte-Carlo simulations

    International Nuclear Information System (INIS)

    Ben Hdech, Yassine

    2011-01-01

    To ensure the required accuracy and prevent from mis-administration, cancer treatments, by external radiation therapy are simulated on Treatment Planning System or TPS before radiation delivery in order to ensure that the prescription is achieved both in terms of target volumes coverage and healthy tissues protection. The TPS calculates the patient dose distribution and the treatment time per beam required to deliver the prescribed dose. TPS is a key system in the decision process of treatment by radiation therapy. It is therefore essential that the TPS be subject to a thorough check of its performance (quality control or QC) and in particular its ability to accurately compute dose distributions for patients in all clinical situations that be met. The 'traditional' methods recommended to carry out dosimetric CQ of algorithms implemented in the TPS are based on comparisons between dose distributions calculated with the TPS and dose measured in physical test objects (PTO) using the treatment machine. In this thesis we propose to substitute the reference dosimetric measurements performed in OTP by benchmark dose calculations in Digital Test Objects using PENELOPE Monte-Carlo code. This method has three advantages: (i) it allows simulation in situations close to the clinic and often too complex to be experimentally feasible; (ii) due to the digital form of reference data the QC process may be automated; (iii) it allows a comprehensive TPS CQ without hindering the use of an equipment devoted primarily to patients treatments. This new method of CQ has been tested successfully on the Eclipse TPS from Varian Medical Systems Company. (author) [fr

  15. Improvement of the electromagnetic situation in networks of operational current at nuclear power plant for the purpose of ensuring reliability of monitoring systems, control, RPA and communications, realized on the basis of digital equipment

    International Nuclear Information System (INIS)

    Fomenko, O.V.; Moloshnaya, E.S.; Ul'yanova, Yu.E.

    2014-01-01

    The authors propose the technique of designing a portable grounding contour for protection and control systems, relay protection and automation (RPA) systems made on the basis of digital equipment in networks of an operational direct current to increase the reliability of their functioning under the conditions of influence of strong hindrances and improvement of an electromagnetic environment [ru

  16. Unattended digital video surveillance: A system prototype for EURATOM safeguards

    International Nuclear Information System (INIS)

    Chare, P.; Goerten, J.; Wagner, H.; Rodriguez, C.; Brown, J.E.

    1994-01-01

    Ever increasing capabilities in video and computer technology have changed the face of video surveillance. From yesterday's film and analog video tape-based systems, we now emerge into the digital era with surveillance systems capable of digital image processing, image analysis, decision control logic, and random data access features -- all of which provide greater versatility with the potential for increased effectiveness in video surveillance. Digital systems also offer other advantages such as the ability to ''compress'' data, providing increased storage capacities and the potential for allowing longer surveillance Periods. Remote surveillance and system to system communications are also a benefit that can be derived from digital surveillance systems. All of these features are extremely important in today's climate Of increasing safeguards activity and decreasing budgets -- Los Alamos National Laboratory's Safeguards Systems Group and the EURATOM Safeguards Directorate have teamed to design and implement a period surveillance system that will take advantage of the versatility of digital video for facility surveillance system that will take advantage of the versatility of digital video for facility surveillance and data review. In this Paper we will familiarize you with system components and features and report on progress in developmental areas such as image compression and region of interest processing

  17. Application of QC_DR software for acceptance testing and routine quality control of direct digital radiography systems: initial experiences using the Italian Association of Physicist in Medicine quality control protocol.

    Science.gov (United States)

    Nitrosi, Andrea; Bertolini, Marco; Borasi, Giovanni; Botti, Andrea; Barani, Adriana; Rivetti, Stefano; Pierotti, Luisa

    2009-12-01

    Ideally, medical x-ray imaging systems should be designed to deliver maximum image quality at an acceptable radiation risk to the patient. Quality assurance procedures are employed to ensure that these standards are maintained. A quality control protocol for direct digital radiography (DDR) systems is described and discussed. Software to automatically process and analyze the required images was developed. In this paper, the initial results obtained on equipment of different DDR manufacturers were reported. The protocol was developed to highlight even small discrepancies in standard operating performance.

  18. Fully integrated digital GAMMA camera-computer system

    International Nuclear Information System (INIS)

    Berger, H.J.; Eisner, R.L.; Gober, A.; Plankey, M.; Fajman, W.

    1985-01-01

    Although most of the new non-nuclear imaging techniques are fully digital, there has been a reluctance in nuclear medicine to abandon traditional analog planar imaging in favor of digital acquisition and display. The authors evaluated a prototype digital camera system (GE STARCAM) in which all of the analog acquisition components are replaced by microprocessor controls and digital circuitry. To compare the relative effects of acquisition matrix size on image quality and to ascertain whether digital techniques could be used in place of analog imaging, Tc-99m bone scans were obtained on this digital system and on a comparable analog camera in 10 patients. The dedicated computer is used for camera setup including definition of the energy window, spatial energy correction, and spatial distortion correction. The display monitor, which is used for patient positioning and image analysis, is 512/sup 2/ non-interlaced, allowing high resolution imaging. Data acquisition and processing can be performed simultaneously. Thus, the development of a fully integrated digital camera-computer system with optimized display should allow routine utilization of non-analog studies in nuclear medicine and the ultimate establishment of fully digital nuclear imaging laboratories

  19. OSIRIS: the first M.T.R. with a new instrumentation and control system based on digital logic of vote

    International Nuclear Information System (INIS)

    Joly, C.; Thiercelin, C.; Corre, J.; Dubois, J.F.; Contenson, G. de.

    1993-01-01

    OSIRIS, one of the french C.E.A. research reactors located at SACLAY, near PARIS, is since 27 years mainly devoted to production and irradiation technologies. To satisfy these objectives, OSIRIS is equipped by different test sections allowing mainly: - the long time irradiation of different materials including fuel rods, reactor vessel materials, fusion reactor components, - the power ramps of fuel rods, the Silicon doping, the radioelements production, the neutronography of materials and test sections. In most of the loops, the nuclear reactor conditions are fully simulated to approach as far as possible the exact behaviour of the materials. Through the new irradiation facilities under development, let's cite the OPERA test section foreseen for the simultaneous irradiation of 32 fuel rods with a maximum length of 2 m. To guarantee the safety and the high performances of the reactor, a continuous maintenance and improvement programme took place during the whole life of the reactor. The paper gives an overview of the part of this programme devoted to the replacement of the instrumentation and control system of the reactor. After 5 years study and development, the on site work took place in the second part of 1992 allowing a reactor start up beginning of 1993. (authors). 10 figs

  20. HIGH RESOLUTION ANALOG / DIGITAL POWER SUPPLY CONTROLLER

    International Nuclear Information System (INIS)

    Medvedko, Evgeny A

    2003-01-01

    Corrector magnets for the SPEAR-3 synchrotron radiation source require precision, high-speed control for use with beam-based orbit feedback. A new Controller Analog/Digital Interface card (CANDI) has been developed for these purposes. The CANDI has a 24-bit DAC for current control and three 24-bit Δ-Σ ADCs to monitor current and voltages. The ADCs can be read and the DAC updated at the 4 kHz rate needed for feedback control. A precision 16-bit DAC provides on-board calibration. Programmable multiplexers control internal signal routing for calibration, testing, and measurement. Feedback can be closed internally on current setpoint, externally on supply current, or beam position. Prototype and production tests are reported in this paper. Noise is better than 17 effective bits in a 10 mHz to 2 kHz bandwidth. Linearity and temperature stability are excellent

  1. Digital Traces of Information Systems

    DEFF Research Database (Denmark)

    Hedman, Jonas; Srinivasan, Nikhil; Lindgren, Rikard

    2013-01-01

    . This disconcerting result suggests that IS researchers must pay more attention to the changing landscape of data sources. To motivate and guide fellow colleagues to establish the credibility and reliability of digital traces, we develop a future research agenda that covers both opportunities in theory generation...

  2. Analog and digital communication systems

    CERN Document Server

    Roden, Martin S

    1996-01-01

    New edition of an introductory text that balances theoretical foundations with practical design. Reorganization and updates in this edition include the section on digital communications as well as design applications and computer exercises: many graphs are prepared and formulas solved using MATLAB...

  3. Experimental OAI-Based Digital Library Systems

    Science.gov (United States)

    Nelson, Michael L. (Editor); Maly, Kurt (Editor); Zubair, Mohammad (Editor); Rusch-Feja, Diann (Editor)

    2002-01-01

    The objective of Open Archives Initiative (OAI) is to develop a simple, lightweight framework to facilitate the discovery of content in distributed archives (http://www.openarchives.org). The focus of the workshop held at the 5th European Conference on Research and Advanced Technology for Digital Libraries (ECDL 2001) was to bring researchers in the area of digital libraries who are building OAI based systems so as to share their experiences, problems they are facing, and approaches they are taking to address them. The workshop consisted of invited talks from well-established researchers working in building OAI based digital library system along with short paper presentations.

  4. Modeling of digital communication systems using SIMULINK

    CERN Document Server

    Giordano, Arthur A

    2015-01-01

    Arthur Giordano, PhD, is a consultant in the field of military and commercial communications specializing in wireless communications. He is a co-founder of G5 Scientific, LLC, is a senior member of the IEEE and has taught graduate communications courses. He has developed numerous models using MathWorks®' SIMULINK®® to characterize digital communications systems. Allen Levesque, PhD, is a consultant specializing in digital communications systems, and is a partner in G5 Scientific, LLC. He has taught graduate courses in digital communications at Worcester Polytechnic Institute and is currently

  5. Photogrammetry, Digital mapping and Land Informations Systems

    DEFF Research Database (Denmark)

    Frederiksen, Poul

    1998-01-01

    Monitoring activities on photogrammetry, digital mapping and land information systems in State Land Service in Latvia in relation to the EU Phare Project Phase II, Technical Assistance to land Privatisation and registration in Latvia.......Monitoring activities on photogrammetry, digital mapping and land information systems in State Land Service in Latvia in relation to the EU Phare Project Phase II, Technical Assistance to land Privatisation and registration in Latvia....

  6. Single Bit Radar Systems for Digital Integration

    OpenAIRE

    Bjørndal, Øystein

    2017-01-01

    Small, low cost, radar systems have exciting applications in monitoring and imaging for the industrial, healthcare and Internet of Things (IoT) sectors. We here explore, and show the feasibility of, several single bit square wave radar architectures; that benefits from the continuous improvement in digital technologies for system-on-chip digital integration. By analysis, simulation and measurements we explore novel and harmonic-rich continuous wave (CW), stepped-frequency CW (SFCW) and freque...

  7. Digital Blood Flow In Systemic Lupus Erythematosus By Photoplethysmography

    Directory of Open Access Journals (Sweden)

    Ghosh Sanjay

    2002-01-01

    Full Text Available Digital vascular status in 10 patients of systemic lupus erythematous (SLE suffering for 1 to 5 years and 5 control (normal subjects was assessed by a highly sensitive, non-invasive technique called photoplethysmography (PPG. Six patients (Group A showed clinical sign. PPG recordings were done by applying the PPG probe serially to the distal phalanges of all the digits of four limbs with Velcro-strap at an ambient temperature of 27 to 31C and humidity 60 to 65% Diminished capillary flow. On average, 12 digits (60% in Group A and 8 digits (40% in group B patients showed reduced blood circulation. Degree of vascular impairment had no bearing upon the duration of the disease. The PPG has objectively shown digital vascular impairment in all SLE patients having no correlation with the extent of clinical manifestations and the duration of the disease.

  8. Digital Autonomous Terminal Access Communication (DATAC) system

    Science.gov (United States)

    Novacki, Stanley M., III

    1987-01-01

    In order to accommodate the increasing number of computerized subsystems aboard today's more fuel efficient aircraft, the Boeing Co. has developed the DATAC (Digital Autonomous Terminal Access Control) bus to minimize the need for point-to-point wiring to interconnect these various systems, thereby reducing total aircraft weight and maintaining an economical flight configuration. The DATAC bus is essentially a local area network providing interconnections for any of the flight management and control systems aboard the aircraft. The task of developing a Bus Monitor Unit was broken down into four subtasks: (1) providing a hardware interface between the DATAC bus and the Z8000-based microcomputer system to be used as the bus monitor; (2) establishing a communication link between the Z8000 system and a CP/M-based computer system; (3) generation of data reduction and display software to output data to the console device; and (4) development of a DATAC Terminal Simulator to facilitate testing of the hardware and software which transfer data between the DATAC's bus and the operator's console in a near real time environment. These tasks are briefly discussed.

  9. High Density Digital Data Storage System

    Science.gov (United States)

    Wright, Kenneth D., II; Gray, David L.; Rowland, Wayne D.

    1991-01-01

    The High Density Digital Data Storage System was designed to provide a cost effective means for storing real-time data from the field-deployable digital acoustic measurement system. However, the high density data storage system is a standalone system that could provide a storage solution for many other real time data acquisition applications. The storage system has inputs for up to 20 channels of 16-bit digital data. The high density tape recorders presently being used in the storage system are capable of storing over 5 gigabytes of data at overall transfer rates of 500 kilobytes per second. However, through the use of data compression techniques the system storage capacity and transfer rate can be doubled. Two tape recorders have been incorporated into the storage system to produce a backup tape of data in real-time. An analog output is provided for each data channel as a means of monitoring the data as it is being recorded.

  10. Using LabVIEW for the design and control of digital signal processing systems. Simulation of the ultra slow extraction at COSY

    International Nuclear Information System (INIS)

    Heinrichs, G.; Rongen, H.; Jamal, R.

    1994-01-01

    For the ultraslow extraction system of the COler SYnchrotron COSY a direct digital synthesis system is being developed. LabVIEW from National Instruments has been chosen as a tool for the simulation of the digital signal processing algorithms as well as the generation of test sequences. In order to generate adjustable band-limited noise centered at a carrier frequency, alternative algorithms have been studied. LabVIEW permits the interactive variation of relevant system parameters by means of a graphical language in order to study the quality of the frequency band limitation as a function of noise parameters, digital accuracy and frequency range and to generate test sequences by means of a real-time function generator. Advantages and limitations of LabVIEW for such applications are discussed. ((orig.))

  11. Digital Components in Swedish NPP Power Systems

    International Nuclear Information System (INIS)

    Karlsson, Mattias; Eriksson, Tage

    2015-01-01

    Swedish nuclear power plants have over the last 20 years of operation modernised or exchanged several systems and components of the electrical power system. Within these works, new components based on digital technology have been employed in order to realize functionality that was previously achieved by using electro-mechanical or analogue technology. Components and systems such as relay protection, rectifiers, inverters, variable speed drives and diesel-generator sets are today equipped with digital components. Several of the systems and components fulfil functions with a safety-role in the NPP. Recently, however, a number of incidents have occurred which highlight deficiencies in the design or HMI of the equipment, which warrants questions whether there are generic problems with some applications of digital components that needs to be addressed. The use of digital components has presented cost effective solutions, or even the only available solution on the market enabling a modernisation. The vast majority of systems using digital components have been operating without problems and often contribute to improved safety but the challenge of non-detectable, or non-identifiable, failure modes remain. In this paper, the extent to which digital components are used in Swedish NPP power systems will be presented including a description of typical applications. Based on data from maintenance records and fault reports, as well as interviews with designers and maintenance personnel, the main areas where problems have been encountered and where possible risks have been identified will be described. The paper intends to investigate any 'tell-tales' that could give signals of unwanted behaviour. Furthermore, particular benefits experienced by using digital components will be highlighted. The paper will also discuss the safety relevance of these findings and suggest measures to improve safety in the application of digital components in power systems. (authors)

  12. Direct digital control of furnaces irradiated in nuclear reactors

    International Nuclear Information System (INIS)

    Joumard, R.

    1969-01-01

    An experimental direct digital control system has been realised in the 'C.E.N.G.', in order to verify that a computer makes easier the control of the experiments done in the nuclear reactors and to solve the theoretical and technical difficulties. The regulation is applied to thermal processes. The sampled data systems theory permits to choose the type of an efficient and simple digital compensator, and to establish a diagram which gives the values of the correcting parameters (obtained by minimizing the difference between the output and the input when perturbations occur). The programme execute, in simultaneity, supervision and regulation. Complex possibilities of printing out measures and alarms existed. The computer works out an incremental correction which makes step motors to turn. These motors act on the heating organs. The theoretical values and answers have been confirmed. The accuracy was limited essentially by the input quantification (1/1000 th). The comfort of such a system has been noticeable. (author) [fr

  13. Intermediate probabilistic safety assessment approach for safety critical digital systems

    International Nuclear Information System (INIS)

    Taeyong, Sung; Hyun Gook, Kang

    2001-01-01

    Even though the conventional probabilistic safety assessment methods are immature for applying to microprocessor-based digital systems, practical needs force to apply it. In the Korea, UCN 5 and 6 units are being constructed and Korean Next Generation Reactor is being designed using the digital instrumentation and control equipment for the safety related functions. Korean regulatory body requires probabilistic safety assessment. This paper analyzes the difficulties on the assessment of digital systems and suggests an intermediate framework for evaluating their safety using fault tree models. The framework deals with several important characteristics of digital systems including software modules and fault-tolerant features. We expect that the analysis result will provide valuable design feedback. (authors)

  14. Digital signal processing in power electronics control circuits

    CERN Document Server

    Sozanski, Krzysztof

    2013-01-01

    Many digital control circuits in current literature are described using analog transmittance. This may not always be acceptable, especially if the sampling frequency and power transistor switching frequencies are close to the band of interest. Therefore, a digital circuit is considered as a digital controller rather than an analog circuit. This helps to avoid errors and instability in high frequency components. Digital Signal Processing in Power Electronics Control Circuits covers problems concerning the design and realization of digital control algorithms for power electronics circuits using

  15. Harmonization of the licensing process for digital instrumentation and control systems in nuclear power plants. Report prepared within the framework of the Technical Working Group on Nuclear Power Plant Control and Instrumentation

    International Nuclear Information System (INIS)

    2002-12-01

    This report was prepared in response to the recommendation of the Technical Working Group on Nuclear Power Plant Control and Instrumentation (TWG-NPPCI). This recommendation was based on the recognition of the present diversity in national practices in licensing digital Instrumentation and control (I and C). The goal of this report is to promote harmonization of I and C licensing requirements in the Member States. It applies to I and C modernization, retrofits, upgrades, replacement, new installation, and other aspects of digital I and C in both existing and new nuclear power plants. It should be pointed out that a single publication, like this report, can only take the first step towards initiating a process leading to licensing requirements, which are more harmonized. It is therefore hoped that that this report will get a broad readership among those who can influence requirements that are set on digital I and C. This report provides general and high level recommendations to assist senior officials at utilities, vendor organizations, regulatory bodies, and their support organizations who are involved in the licensing of digital I and C. It is also intended to be read by persons participating in technical committees which are writing standards. The authors of this report believe that harmonization can be achieved through a consideration of the technical and scientific basis of high integrity digital I and C systems. It is also believed that many benefits can be reached in resolving various issues of a technical and engineering nature, which presently are creating controversies in the licensing of digital I and C in NPP safety applications. This publication is based on a consideration of the licensing process of I and C in a top down fashion to discuss generic principles to be applied when assessing digital I and C in NPP safety applications. This report gives an overview of the confidence building process in which evidence is created that digital I and C fulfils

  16. Proceedings: Electromagnetic interference control in modern digital instrumentation and control upgrades

    International Nuclear Information System (INIS)

    1993-06-01

    A workshop on Electro-Magnetic Interference (EMI) Control in Modern Digital Instrumentation ampersand Control System Upgrade was held in Baltimore on September 10-11, 1992 to provide a forum for technology transfer, technical information exchange, and education. The workshop was attended by more than 70 representatives of electric utilities, equipment manufacturers, engineering consulting organizations, and government agencies. The workshop consists of four sessions: (1) Organizational EMC Perspectives, (2) EMI Environment, Case Histories ampersand Solutions, (3) EMC in Digital Instrumentation ampersand Control Systems, and (4) EMI Utility Needs. A group discussion followed the presentations to identify utility needs. Individual papers have been cataloged separately

  17. Licensing of digital Instrumentation and Control in Radioisotope Production Facility

    International Nuclear Information System (INIS)

    Abdel-Aziz, L.Kh.; Lashin, R.; Mostafa, W.

    2012-01-01

    In spite of the rapid development of digital I and C systems in all major industries, it has for several reasons been slower in nuclear power plants. The most important reason is that only a few new plants have been ordered worldwide during the last ten years. A second reason is connected to the efforts needed in providing adequate evidence that the digital I and C system can be used in safety and safety related applications. This issue is connected to the effort needed in obtaining adequate assurance that the digital I and C will fulfill its intended function and contain no unintended function in all possible operational states during its entire life cycle. This paper presents an acceptance criteria for licensing a digital instrumentation and control system in a Radioisotope Production Facility(1), which is under commissioning. The acceptance criteria ensure that the I and C systems are designed to reach the highest degree of reliability with respect to the function they perform, operators will have clear and accessible availability to data on every plant parameter, and also ensure that the safety objectives have been covered

  18. A digital video tracking system

    Science.gov (United States)

    Giles, M. K.

    1980-01-01

    The Real-Time Videotheodolite (RTV) was developed in connection with the requirement to replace film as a recording medium to obtain the real-time location of an object in the field-of-view (FOV) of a long focal length theodolite. Design philosophy called for a system capable of discriminatory judgment in identifying the object to be tracked with 60 independent observations per second, capable of locating the center of mass of the object projection on the image plane within about 2% of the FOV in rapidly changing background/foreground situations, and able to generate a predicted observation angle for the next observation. A description is given of a number of subsystems of the RTV, taking into account the processor configuration, the video processor, the projection processor, the tracker processor, the control processor, and the optics interface and imaging subsystem.

  19. An Introduction to Digital Rights Management Systems

    NARCIS (Netherlands)

    Jonker, Willem

    2007-01-01

    This chapter gives a concise introduction to digital rights management (DRM) systems by first presenting the basic ingredients of the architecture of DRM systems for (audio and/or video) content delivery, followed by an introduction to two open-standard DRM systems, one developed in the mobile world

  20. Digital image display system for emergency room

    International Nuclear Information System (INIS)

    Murry, R.C.; Lane, T.J.; Miax, L.S.

    1989-01-01

    This paper reports on a digital image display system for the emergency room (ER) in a major trauma hospital. Its objective is to reduce radiographic image delivery time to a busy ER while simultaneously providing a multimodality capability. Image storage, retrieval, and display will also be facilitated with this system. The system's backbone is a token-ring network of RISC and personal computers. The display terminals are higher- function RISC computers with 1,024 2 color or gray-scale monitors. The PCs serve as administrative terminals. Nuclear medicine, CT, MR, and digitized film images are transferred to the image display system

  1. Application of digital control techniques for satellite medium power DC-DC converters

    Science.gov (United States)

    Skup, Konrad R.; Grudzinski, Pawel; Nowosielski, Witold; Orleanski, Piotr; Wawrzaszek, Roman

    2010-09-01

    The objective of this paper is to present a work concerning a digital control loop system for satellite medium power DC-DC converters that is done in Space Research Centre. The whole control process of a described power converter bases on a high speed digital signal processing. The paper presents a development of a FPGA digital controller for voltage mode stabilization that was implemented using VHDL. The described controllers are a classical digital PID controller and a bang-bang controller. The used converter for testing is a simple model of 5-20 W, 200 kHz buck power converter. A high resolution digital PWM approach is presented. Additionally a simple and effective solution of filtering of an analog-to-digital converter output is presented.

  2. A new digital land mobile satellite system

    Science.gov (United States)

    Schneider, Philip

    A description is given of the different digital services planned to be carried over existing and planned mobile satellite systems. These systems are then compared with analog services in terms of bandwidth and power efficiency. This comparison provides the rationale for the establishment of a digital land mobile satellite service (DLMSS) to use frequencies that are currently available but not yet assigned to a domestic mobile satellite system in the United States. The focus here is on the expected advantages of digital transmission techniques in accommodating additional mobile satellite systems in this portion of the spectrum, and how such techniques can fully satisfy voice, data and facsimile mobile communications requirements in a cost effective manner. A description is given of the system architecture of the DMLSS service proposed by the Geostar Messaging Corporation (GMC) and the market potential of DLMSS.

  3. Design of digital voice storage and playback system

    Science.gov (United States)

    Tang, Chao

    2018-03-01

    Based on STC89C52 chip, this paper presents a single chip microcomputer minimum system, which is used to realize the logic control of digital speech storage and playback system. Compared with the traditional tape voice recording system, the system has advantages of small size, low power consumption, The effective solution of traditional voice recording system is limited in the use of electronic and information processing.

  4. Investigation, development and application of optimal output feedback theory. Volume 2: Development of an optimal, limited state feedback outer-loop digital flight control system for 3-D terminal area operation

    Science.gov (United States)

    Broussard, J. R.; Halyo, N.

    1984-01-01

    This report contains the development of a digital outer-loop three dimensional radio navigation (3-D RNAV) flight control system for a small commercial jet transport. The outer-loop control system is designed using optimal stochastic limited state feedback techniques. Options investigated using the optimal limited state feedback approach include integrated versus hierarchical control loop designs, 20 samples per second versus 5 samples per second outer-loop operation and alternative Type 1 integration command errors. Command generator tracking techniques used in the digital control design enable the jet transport to automatically track arbitrary curved flight paths generated by waypoints. The performance of the design is demonstrated using detailed nonlinear aircraft simulations in the terminal area, frequency domain multi-input sigma plots, frequency domain single-input Bode plots and closed-loop poles. The response of the system to a severe wind shear during a landing approach is also presented.

  5. Development and application of digital safety system in NPPs

    International Nuclear Information System (INIS)

    Kwon, Keechoon; Kim, Changhwoi; Lee, Dongyoung

    2012-01-01

    This paper describes the development of digital safety system in NPPs based on safety- grade programmable logic controller (PLC) platform and its application to real NPP construction. The digital safety system consists of a reactor protection system and an engineered safety feature-component control system. The safety-grade PLC platform was developed so that it meets the requirements of the regulation. The PLC consists of various modules such as a power module, a processor module, communication modules, digital input/output modules, analog input/output modules, a LOCA bus extension module, and a high-speed pulse counter module. The reactor protection system is designed with a redundant 4-channel architecture, and every channel is implemented with the same architecture. A single channel consists of a redundant bi-stable processor, a redundant coincidence processor, an automatic test and interface processor, and a cabinet operator module. The engineered safety feature-component control system is designed with four redundant divisions, and implemented with the PLC platform. The principal components of an individual division are fault tolerant group controllers, loop controllers, a test and interface processor, a cabinet operator module and a control channel gateway. The topical report is submitted to the regulatory body, and got safety evaluation report from the regulatory body. Also, the developed system is tested in the integrated performance validation facility. It is decided that the digital safety system applied to Shin-Uljin unit 1 and 2 after a topical report approval and validation test. Design changes occur in the digital safety system that is applied to an actual nuclear power plant construction, and the PLC has also been upgraded

  6. Development and application of digital safety system in NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Keechoon; Kim, Changhwoi; Lee, Dongyoung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-03-15

    This paper describes the development of digital safety system in NPPs based on safety- grade programmable logic controller (PLC) platform and its application to real NPP construction. The digital safety system consists of a reactor protection system and an engineered safety feature-component control system. The safety-grade PLC platform was developed so that it meets the requirements of the regulation. The PLC consists of various modules such as a power module, a processor module, communication modules, digital input/output modules, analog input/output modules, a LOCA bus extension module, and a high-speed pulse counter module. The reactor protection system is designed with a redundant 4-channel architecture, and every channel is implemented with the same architecture. A single channel consists of a redundant bi-stable processor, a redundant coincidence processor, an automatic test and interface processor, and a cabinet operator module. The engineered safety feature-component control system is designed with four redundant divisions, and implemented with the PLC platform. The principal components of an individual division are fault tolerant group controllers, loop controllers, a test and interface processor, a cabinet operator module and a control channel gateway. The topical report is submitted to the regulatory body, and got safety evaluation report from the regulatory body. Also, the developed system is tested in the integrated performance validation facility. It is decided that the digital safety system applied to Shin-Uljin unit 1 and 2 after a topical report approval and validation test. Design changes occur in the digital safety system that is applied to an actual nuclear power plant construction, and the PLC has also been upgraded.

  7. Circuit, especially for digital nuclear gyroscope systems

    International Nuclear Information System (INIS)

    Lowdenslager, J.R.

    1974-01-01

    The circuit with at least one or two spin generator shows a digital phase synchronizing loop in solid-state construction without movable mechanical parts. It is stable, may be turned in one direction any number of times without saturation, and also remains phase-synchronized when input signals are turned off. For this purpose, crystal oscillators with certain resonance frequencies are used. The spin generators are coupled at the outled side with filtering, squaring, and differential connections generating control impulses synchronous to the spin generators. Step divider circuits are connected to the oscillators, which act upon flip-flop registers. This is controlled by the filtering, squaring, and differential connections. Furthermore, field proportional control circuits with registers, advancing and delay circuits are provided, the registers being connected at the outlet side with digital adders and subtractors. The digital adder serves inertial-related purposes. (DG) [de

  8. Digital computer control of a research nuclear reactor

    International Nuclear Information System (INIS)

    Crawford, Kevan

    1986-01-01

    Currently, the use of digital computers in energy producing systems has been limited to data acquisition functions. These computers have greatly reduced human involvement in the moment to moment decision process and the crisis decision process, thereby improving the safety of the dynamic energy producing systems. However, in addition to data acquisition, control of energy producing systems also includes data comparison, decision making, and control actions. The majority of the later functions are accomplished through the use of analog computers in a distributed configuration. The lack of cooperation and hence, inefficiency in distributed control, and the extent of human interaction in critical phases of control have provided the incentive to improve the later three functions of energy systems control. Properly applied, centralized control by digital computers can increase efficiency by making the system react as a single unit and by implementing efficient power changes to match demand. Additionally, safety will be improved by further limiting human involvement to action only in the case of a failure of the centralized control system. This paper presents a hardware and software design for the centralized control of a research nuclear reactor by a digital computer. Current nuclear reactor control philosophies which include redundancy, inherent safety in failure, and conservative yet operational scram initiation were used as the bases of the design. The control philosophies were applied to the power monitoring system, the fuel temperature monitoring system, the area radiation monitoring system, and the overall system interaction. Unlike the single function analog computers that are currently used to control research and commercial reactors, this system will be driven by a multifunction digital computer. Specifically, the system will perform control rod movements to conform with operator requests, automatically log the required physical parameters during reactor

  9. SECURING DIGITIZED LIBRARY CIRCULATORY SYSTEM

    African Journals Online (AJOL)

    user

    The widespread application of the developed system on smart library circulation .... database management system; [9] through securing .... system running on a Windows 8 Operating system .... mini library for their support, advice and unlimited.

  10. KAERI software safety guideline for developing safety-critical software in digital instrumentation and control system of nuclear power plant

    International Nuclear Information System (INIS)

    Lee, Jang Soo; Kim, Jang Yeol; Eum, Heung Seop.

    1997-07-01

    Recently, the safety planning for safety-critical software systems is being recognized as the most important phase in the software life cycle, and being developed new regulatory positions and standards by the regulatory and the standardization organization. The requirements for software important to safety of nuclear reactor are described in such positions and standards. Most of them are describing mandatory requirements, what shall be done, for the safety-critical software. The developers of such a software. However, there have been a lot of controversial factors on whether the work practices satisfy the regulatory requirements, and to justify the safety of such a system developed by the work practices, between the licenser and the licensee. We believe it is caused by the reason that there is a gap between the mandatory requirements (What) and the work practices (How). We have developed a guidance to fill such gap, which can be useful for both licenser and licensee to conduct a justification of the safety in the planning phase of developing the software for nuclear reactor protection systems. (author). 67 refs., 13 tabs., 2 figs

  11. KAERI software safety guideline for developing safety-critical software in digital instrumentation and control system of nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jang Soo; Kim, Jang Yeol; Eum, Heung Seop

    1997-07-01

    Recently, the safety planning for safety-critical software systems is being recognized as the most important phase in the software life cycle, and being developed new regulatory positions and standards by the regulatory and the standardization organization. The requirements for software important to safety of nuclear reactor are described in such positions and standards. Most of them are describing mandatory requirements, what shall be done, for the safety-critical software. The developers of such a software. However, there have been a lot of controversial factors on whether the work practices satisfy the regulatory requirements, and to justify the safety of such a system developed by the work practices, between the licenser and the licensee. We believe it is caused by the reason that there is a gap between the mandatory requirements (What) and the work practices (How). We have developed a guidance to fill such gap, which can be useful for both licenser and licensee to conduct a justification of the safety in the planning phase of developing the software for nuclear reactor protection systems. (author). 67 refs., 13 tabs., 2 figs.

  12. NRC perspectives on the digital system review process

    International Nuclear Information System (INIS)

    Mauck, J.L.

    1998-01-01

    Since about 1988, the USNRC has been involved in the review of digital retrofits to instrumentation and control (I and C) systems in nuclear power plants. Initially, this involvement was limited but with the advent of the 1990s, NRC involvement has become greater because of increased interest in and application of digital systems as existing analog systems become obsolete. Criteria for the design of such systems to ensure safety has been promulgated over the years and the USNRC has been actively involved both nationally and internationally with this effort. With the publication of the Zion Eagle 21 Safety Evaluation Report in 1992, Generic Letter 95-02 in April 1995 which endorses EPRI guidance document TR-102348 on digital upgrades and the latest revision to Regulatory Guide 1.152 which endorses IEEE 7.4.3.2-1993; a basic digital system review process was established. The NRC supplemented this review process with recently issued inspection procedures for use by NRC inspectors when conducting onsite reviews of digital modifications. In addition, the NRC undertook a major effort to codify the above guidance and the experience gained from digital system reviews of both operating plant modifications and advanced reactor designs, over these years into a revision to Standard Review Plan, (SRP), NUREG-0800, Chapter 7, Instrumentation and Control. This SRP revision was published in June, 1997, and included new SRP sections, branch technical positions and six new regulatory guides endorsing IEEE standards on software quality. The NRC staff believes that a stable digital system review process is now in place. (author)

  13. Advantages of digital radiography: The DSI system

    International Nuclear Information System (INIS)

    Drouillard, J.

    1990-01-01

    The experience gained over a period of several months, applying the digital and image-enhanced radiography with the DSI system for examination of some hundreds of patients, has confirmed in our eyes the system's diagnostic and economic efficiency, and the important achievement of radiation dose abatement. Looking at the current results and improvements under way (Release 2), there is reason enough to support an extension of the range of indications, especially regarding arteriography and interventional radiography. According to our experience, the DSI system meets the requirements of a modern radiology department: reduction of operating costs, limitation of radiation dose, efficiency enhancement by digital imaging. (orig.) [de

  14. Reliability analysis of digital based I and C system

    Energy Technology Data Exchange (ETDEWEB)

    Kang, I. S.; Cho, B. S.; Choi, M. J. [KOPEC, Yongin (Korea, Republic of)

    1999-10-01

    Rapidly, digital technology is being widely applied in replacing analog component installed in existing plant and designing new nuclear power plant for control and monitoring system in Korea as well as in foreign countries. Even though many merits of digital technology, it is being faced with a new problem of reliability assurance. The studies for solving this problem are being performed vigorously in foreign countries. The reliability of KNGR Engineered Safety Features Component Control System (ESF-CCS), digital based I and C system, was analyzed to verify fulfillment of the ALWR EPRI-URD requirement for reliability analysis and eliminate hazards in design applied new technology. The qualitative analysis using FMEA and quantitative analysis using reliability block diagram were performed. The results of analyses are shown in this paper.

  15. Synthesis of optimal digital controller of flocculant dosing

    Directory of Open Access Journals (Sweden)

    A.V. Pismenskiy

    2013-06-01

    Full Text Available Purpose. The task of automatic process control of the slime water thickening and flotation tailings clarification is the stabilization of thicken product density within the given range and keeping up the solids content in the overflow not above the permissible level with minimum use of the flocculants. In existing systems for automatic control the flocculant dosing is carried out according to the solids content in the device input (the principle of open-loop control. This leads to the excess consumption of the flocculants and increase the dispersion density of the overflow. To perform the synthesis of the optimal digital controller in order to minimize the deviations from the master control and ensure the specified quality of the transition process. Over controlling value should not exceed 5 %. To perform the system operation modeling in order to determine the quality of transient processes. Methodology. Synthesis of the optimal digital controller is based on the method of dynamic programming. Findings. A mathematical model of the object control is represented in the normal form of Cauchy and further in the form of differential equations. The optimum period of quantization as the function from specified error of control and the output coordinate change is calculated. The differential equation of Bellman is obtained and the condition for minimization of the quality functional. Bellman function is represented as a quadratic form from the variables of the system condition. In order to limit possible control, the weight coefficients of the functional are calculated based on maximum permitted values of the system condition variables and the control actions during the transient process. Practical value. Using the modeling of ACS of the flocculant dosing it was established that the over controlling amount is 3.5%, the transient process life 5.6 sec, the transient process is aperiodical, non-static control, which meets the requirements imposed on the

  16. Digitally controlled analog proportional-integral-derivative (PID) controller for high-speed scanning probe microscopy

    Science.gov (United States)

    Dukic, Maja; Todorov, Vencislav; Andany, Santiago; Nievergelt, Adrian P.; Yang, Chen; Hosseini, Nahid; Fantner, Georg E.

    2017-12-01

    Nearly all scanning probe microscopes (SPMs) contain a feedback controller, which is used to move the scanner in the direction of the z-axis in order to maintain a constant setpoint based on the tip-sample interaction. The most frequently used feedback controller in SPMs is the proportional-integral (PI) controller. The bandwidth of the PI controller presents one of the speed limiting factors in high-speed SPMs, where higher bandwidths enable faster scanning speeds and higher imaging resolution. Most SPM systems use digital signal processor-based PI feedback controllers, which require analog-to-digital and digital-to-analog converters. These converters introduce additional feedback delays which limit the achievable imaging speed and resolution. In this paper, we present a digitally controlled analog proportional-integral-derivative (PID) controller. The controller implementation allows tunability of the PID gains over a large amplification and frequency range, while also providing precise control of the system and reproducibility of the gain parameters. By using the analog PID controller, we were able to perform successful atomic force microscopy imaging of a standard silicon calibration grating at line rates up to several kHz.

  17. Quality control in digital mammography: the noise components

    International Nuclear Information System (INIS)

    Leyton, Fernando; Nogueira, Maria do Socorro; Duran, Maria Paz; Dantas, Marcelino; Ubeda, Carlos

    2011-01-01

    To measure the linearity of the detector and determine the noise components (quantum, electronic and structural noise) that contributed to losing image quality and to determine the signal noise ratio (SNR) and contrast noise ratio (CNR). This paper describes the results of the implementation of a protocol for quality control in digital mammography performed in two direct digital mammography equipment (Hologic, Selenia) in Santiago of Chile. Shows the results of linearity and noise analysis of the images which establishes the main cause of noise in the image of the mammogram to ensure the quality and optimize procedures. The study evaluated two digital mammography's Selenia, Hologic (DR) from Santiago, Chile. We conducted the assessment of linearity of the detector, the signal noise ratio, contrast noise ratio and was determined the contribution of different noise components (quantum, electronics and structural noise). Used different thicknesses used in clinical practice according to the protocol for quality control in digital mammography of Spanish society of medical physics and NHSBSP Equipment Report 0604 Version 3. The Selenia mammography software was used for the analysis of images and Unfors Xi detector for measuring doses. The mammography detector has a linear performance, the CNR and SNR did not comply with the Protocol for the thicknesses of 60 and 70 mm. The main contribution of the noise corresponds to the quantum noise, therefore it is necessary to adjust and optimize the mammography system. (author)

  18. Quality control in digital mammography: the noise components

    Energy Technology Data Exchange (ETDEWEB)

    Leyton, Fernando [Universidade de Tarapaca, Arica (Chile). Centro de Estudios en Ciencias Radiologicas; Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Nogueira, Maria do Socorro, E-mail: mnogue@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Duran, Maria Paz [Clinica Alemana, Santiago (Chile). Dept. de Radiologia; Dantas, Marcelino, E-mail: marcelino@inb.gov.b [Industrias Nucleares do Brasil (INB), Caldas, MG (Brazil). Unidade de Tratamento de Minerios; Ubeda, Carlos, E-mail: cubeda@uta.c [Universidade de Tarapaca, Arica (Chile). Fac. de Ciencias de la Salud

    2011-07-01

    To measure the linearity of the detector and determine the noise components (quantum, electronic and structural noise) that contributed to losing image quality and to determine the signal noise ratio (SNR) and contrast noise ratio (CNR). This paper describes the results of the implementation of a protocol for quality control in digital mammography performed in two direct digital mammography equipment (Hologic, Selenia) in Santiago of Chile. Shows the results of linearity and noise analysis of the images which establishes the main cause of noise in the image of the mammogram to ensure the quality and optimize procedures. The study evaluated two digital mammography's Selenia, Hologic (DR) from Santiago, Chile. We conducted the assessment of linearity of the detector, the signal noise ratio, contrast noise ratio and was determined the contribution of different noise components (quantum, electronics and structural noise). Used different thicknesses used in clinical practice according to the protocol for quality control in digital mammography of Spanish society of medical physics and NHSBSP Equipment Report 0604 Version 3. The Selenia mammography software was used for the analysis of images and Unfors Xi detector for measuring doses. The mammography detector has a linear performance, the CNR and SNR did not comply with the Protocol for the thicknesses of 60 and 70 mm. The main contribution of the noise corresponds to the quantum noise, therefore it is necessary to adjust and optimize the mammography system. (author)

  19. Image digitizer system for bubble chamber laser

    International Nuclear Information System (INIS)

    Haggerty, H.

    1986-01-01

    An IBM PC-based image digitizer system has been assembled to monitor the laser flash used for holography at the 15 foot bubble chamber. The hardware and the operating software are outlined. For an operational test of the system, an array of LEDs was flashed with a 10 microsecond pulse and the image was grabbed by one of the operating programs and processed

  20. ISTTOK control system upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Ivo S., E-mail: ivoc@ipfn.ist.utl.pt; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Carvalho, Bernardo B.

    2013-10-15

    Highlights: •ISTTOK fast controller. •All real-time diagnostic and actuators were integrated in the control platform. •100 μs control cycle under the MARTe framework. •The ISTTOK control system upgrade provides reliable operation with an improved operational space. -- Abstract: The ISTTOK tokamak (Ip = 4 kA, BT = 0.5 T, R = 0.46 m, a = 0.085 m) is one of the few tokamaks with regular alternate plasma current (AC) discharges scientific programme. In order to improve the discharge stability and to increase the number of AC discharge cycles a novel control system was developed. The controller acquires data from 50 analog-to-digital converter (ADC) channels of real-time diagnostics and measurements: tomography, Mirnov coils, interferometer, electric probes, sine and cosine probes, bolometer, current delivered by the power supplies, loop voltage and plasma current. The system has a control cycle of 100 μs during which it reads all the diagnostics connected to the advanced telecommunications computing architecture (ATCA) digitizers and sends the control reference to ISTTOK actuators. The controller algorithms are executed on an Intel{sup ®} Q8200 chip with 4 cores running at 2.33 GHz and connected to the I/O interfaces through an ATCA based environment. The real-time control system was programmed in C++ on top of the Multi-threaded Application Real-Time executor (MARTe). To extend the duration of the AC discharges and the plasma stability a new magnetising field power supply was commissioned and the horizontal and vertical field power supplies were also upgraded. The new system also features a user-friendly interface based on HyperText Markup Language (HTML) and Javascript to configure the controller parameters. This paper presents the ISTTOK control system and the consequent update of real-time diagnostics and actuators.

  1. ISTTOK control system upgrade

    International Nuclear Information System (INIS)

    Carvalho, Ivo S.; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Carvalho, Bernardo B.

    2013-01-01

    Highlights: •ISTTOK fast controller. •All real-time diagnostic and actuators were integrated in the control platform. •100 μs control cycle under the MARTe framework. •The ISTTOK control system upgrade provides reliable operation with an improved operational space. -- Abstract: The ISTTOK tokamak (Ip = 4 kA, BT = 0.5 T, R = 0.46 m, a = 0.085 m) is one of the few tokamaks with regular alternate plasma current (AC) discharges scientific programme. In order to improve the discharge stability and to increase the number of AC discharge cycles a novel control system was developed. The controller acquires data from 50 analog-to-digital converter (ADC) channels of real-time diagnostics and measurements: tomography, Mirnov coils, interferometer, electric probes, sine and cosine probes, bolometer, current delivered by the power supplies, loop voltage and plasma current. The system has a control cycle of 100 μs during which it reads all the diagnostics connected to the advanced telecommunications computing architecture (ATCA) digitizers and sends the control reference to ISTTOK actuators. The controller algorithms are executed on an Intel ® Q8200 chip with 4 cores running at 2.33 GHz and connected to the I/O interfaces through an ATCA based environment. The real-time control system was programmed in C++ on top of the Multi-threaded Application Real-Time executor (MARTe). To extend the duration of the AC discharges and the plasma stability a new magnetising field power supply was commissioned and the horizontal and vertical field power supplies were also upgraded. The new system also features a user-friendly interface based on HyperText Markup Language (HTML) and Javascript to configure the controller parameters. This paper presents the ISTTOK control system and the consequent update of real-time diagnostics and actuators

  2. Oscilloscope trace photograph digitizing system (TRACE)

    International Nuclear Information System (INIS)

    Richards, M.; Dabbs, R.D.

    1977-10-01

    The digitizing system allows digitization of photographs or sketches of waveforms and then the computer is used to reduce and analyze the data. The software allows for alignment, calibration, removal of baselines, removal of unwanted points and addition of new points which makes for a fairly versatile system as far as data reduction and manipulation are concerned. System considerations are introduced first to orient the potential user to the process of digitizing information. The start up and actual commands for TRACE are discussed. Detailed descriptions of each subroutine and program section are also provided. Three general examples of typical photographs are included. A partial listing of FAWTEK is made available. Once suitable arrays that contain the data are arranged, ''GO FA'' (active FAWTEK) and many mathematical operations to further analyze the data may be performed

  3. Unified Digital Periodic Signal Filters for Power Converter Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Xin, Zhen; Zhou, Keliang

    2017-01-01

    Periodic signal controllers like repetitive and resonant controllers have demonstrated much potential in the control of power electronic converters, where periodic signals (e.g., ac voltages and currents) can be precisely regulated to follow references. Beyond the control of periodic signals, ac...... signal processing (e.g., in synchronization and pre-filtering) is also very important for power converter systems. Hence, this paper serves to unify digital periodic signal filters so as to maximize their roles in power converter systems (e.g., enhance the control of ac signals). The unified digital...... periodic signal filters behave like a comb filter, but it can also be configured to selectively filter out the harmonics of interest (e.g., the odd-order harmonics in single-phase power converter systems). Moreover, a virtual variable-sampling-frequency unit delay that enables frequency adaptive periodic...

  4. A new digital correlation flaw detection system

    International Nuclear Information System (INIS)

    Lee, B.B.; Furgason, E.S.

    1981-01-01

    A new portable digital random signal flaw detection system is described which uses a digital delay line to replace the acoustic delay line of the original random signal system. Using this new system, a comparison was made between the two types of transmit signals which have been used in previous systems--m-sequences and random signals. This comparison has not been possible with these previous correlation flaw detection systems. Results indicated that for high-speed short code operation, the m-sequences produced slightly lower range sidelobes than typical samples of a clipped random signal. For normal long code operation, results indicated that system performance is essentially equivalent in resolution and signal-to-noise ratio using either m-sequences or clipped and sampled random signals. Further results also showed that for normal long code operation, the system produces outputs equivalent in resolution to pulse-echo systems, but with the added benefit of signal-to-noise ratio enhancement

  5. Digital instrumentation system for nuclear research reactors

    International Nuclear Information System (INIS)

    Aghina, Mauricio A.C.; Carvalho, Paulo Vitor R.

    2002-01-01

    This work describes a proposal for a system of nuclear instrumentation and safety totally digital for the Argonauta Reactor. The system divides in the subsystems: channel of pulses, channel of current, conventional instrumentation and safety system. The connection of the subsystems is made through redundant double local net, using the protocol modbus/rtu. So much the channel of pulses, the current channel and safety's system use modules operating in triple redundancy. (author)

  6. Digital PIV (DPIV) Software Analysis System

    Science.gov (United States)

    Blackshire, James L.

    1997-01-01

    A software package was developed to provide a Digital PIV (DPIV) capability for NASA LaRC. The system provides an automated image capture, test correlation, and autocorrelation analysis capability for the Kodak Megaplus 1.4 digital camera system for PIV measurements. The package includes three separate programs that, when used together with the PIV data validation algorithm, constitutes a complete DPIV analysis capability. The programs are run on an IBM PC/AT host computer running either Microsoft Windows 3.1 or Windows 95 using a 'quickwin' format that allows simple user interface and output capabilities to the windows environment.

  7. Security Information System Digital Simulation

    OpenAIRE

    Tao Kuang; Shanhong Zhu

    2015-01-01

    The study built a simulation model for the study of food security information system relay protection. MATLAB-based simulation technology can support the analysis and design of food security information systems. As an example, the food security information system fault simulation, zero-sequence current protection simulation and transformer differential protection simulation are presented in this study. The case studies show that the simulation of food security information system relay protect...

  8. Addressing the susceptibility of digital systems to electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1993-01-01

    This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Second, a verification and validation (V ampersand V) program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate acceptance criteria to ensure that the circuit or system under test meets the recommended guidelines. V ampersand V should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation susceptibility attributable to EMI will be greatly reduced

  9. Digital feedwater and recirculation flow control for GPUN Oyster Creek

    International Nuclear Information System (INIS)

    Burjorjee, D.; Gan, B.

    1992-01-01

    This paper describes the digital system for feedwater and recirculation control that GPU Nuclear will be installing at Oyster Creek during its next outage - expected circa December 1992. The replacement was motivated by considerations of reliability and obsolescence - the analog equipment was aging and reaching the end of its useful life. The new system uses Atomic Energy of Canada Ltd.'s software platform running on dual, redundant, industrial-grade 386 computers with opto-isolated field input/output (I/O) accessed through a parallel bus. The feedwater controller controls three main feed regulating valves, two low flow regulating valves, and two block valves. The recirculation controller drives the five scoop positioners of the hydraulic couplers. The system also drives contacts that lock up the actuators on detecting an open circuit in their current loops

  10. Safety aspect of digital reactor protection system in Japan

    International Nuclear Information System (INIS)

    Ogiso, Zen-Ichi

    1998-01-01

    It was early in 1980's that the digital controllers were first applied to nuclear power plant in japan. After that, their application area had been expanding gradually, reaching to the overall integrated digital system including the safety system in Kashiwazaki-Kariwa units 6 and 7. The software for computer-based systems has been produced using the graphical language ''POL'' in Japanese nuclear power plants. It is the fundamental principle that the reliability of the software should be assured through the properly managed quality assurance. The POL-based system is fitted to this principle. In applying POL-based systems to safety system, the MITI, Ministry of International Trade and Industry, identified the licensing issues as the regulatory body, while the utilities had developed the digital technology feasible to the safety application. Through the activities, a specific industrial design guide for the software important to safety was established and the adequacy of the technology was certified through the demonstration tests of the integrated system. In the safety examination of the digital reactor protection system of K-6/7, the application of POL were approved. The POL-based systems in nuclear power plants were successful design and production process of the POL-based systems. This paper describes the activities in licensing and maintaining the computer-based systems by the utilities and manufacturers as well as the MITI. (author)

  11. Direct drive digital servo press with high parallel control

    Science.gov (United States)

    Murata, Chikara; Yabe, Jun; Endou, Junichi; Hasegawa, Kiyoshi

    2013-12-01

    Direct drive digital servo press has been developed as the university-industry joint research and development since 1998. On the basis of this result, 4-axes direct drive digital servo press has been developed and in the market on April of 2002. This servo press is composed of 1 slide supported by 4 ball screws and each axis has linearscale measuring the position of each axis with high accuracy less than μm order level. Each axis is controlled independently by servo motor and feedback system. This system can keep high level parallelism and high accuracy even with high eccentric load. Furthermore the 'full stroke full power' is obtained by using ball screws. Using these features, new various types of press forming and stamping have been obtained by development and production. The new stamping and forming methods are introduced and 'manufacturing' need strategy of press forming with high added value and also the future direction of press forming are also introduced.

  12. Digital Fractional Order Controllers Realized by PIC Microprocessor: Experimental Results

    OpenAIRE

    Petras, I.; Grega, S.; Dorcak, L.

    2003-01-01

    This paper deals with the fractional-order controllers and their possible hardware realization based on PIC microprocessor and numerical algorithm coded in PIC Basic. The mathematical description of the digital fractional -order controllers and approximation in the discrete domain are presented. An example of realization of the particular case of digital fractional-order PID controller is shown and described.

  13. Fully Digital Chaotic Differential Equation-based Systems And Methods

    KAUST Repository

    Radwan, Ahmed Gomaa Ahmed

    2012-09-06

    Various embodiments are provided for fully digital chaotic differential equation-based systems and methods. In one embodiment, among others, a digital circuit includes digital state registers and one or more digital logic modules configured to obtain a first value from two or more of the digital state registers; determine a second value based upon the obtained first values and a chaotic differential equation; and provide the second value to set a state of one of the plurality of digital state registers. In another embodiment, a digital circuit includes digital state registers, digital logic modules configured to obtain outputs from a subset of the digital shift registers and to provide the input based upon a chaotic differential equation for setting a state of at least one of the subset of digital shift registers, and a digital clock configured to provide a clock signal for operating the digital shift registers.

  14. Fully Digital Chaotic Differential Equation-based Systems And Methods

    KAUST Repository

    Radwan, Ahmed Gomaa Ahmed; Zidan, Mohammed A.; Salama, Khaled N.

    2012-01-01

    Various embodiments are provided for fully digital chaotic differential equation-based systems and methods. In one embodiment, among others, a digital circuit includes digital state registers and one or more digital logic modules configured to obtain a first value from two or more of the digital state registers; determine a second value based upon the obtained first values and a chaotic differential equation; and provide the second value to set a state of one of the plurality of digital state registers. In another embodiment, a digital circuit includes digital state registers, digital logic modules configured to obtain outputs from a subset of the digital shift registers and to provide the input based upon a chaotic differential equation for setting a state of at least one of the subset of digital shift registers, and a digital clock configured to provide a clock signal for operating the digital shift registers.

  15. Noise analysis of a digital radiography system

    International Nuclear Information System (INIS)

    Arnold, B.A.; Scheibe, P.O.

    1984-01-01

    The sources of noise in a digital video subtraction angiography system were identified and analyzed. Signal-to-noise ratios of digital radiography systems were measured using the digital image data recorded in the computer. The major sources of noise include quantum noise, TV camera electronic noise, quantization noise from the analog-to-digital converter, time jitter, structure noise in the image intensifier, and video recorder electronic noise. A new noise source was identified, which results from the interplay of fixed pattern noise and the lack of image registration. This type of noise may result from image-intensifier structure noise in combination with TV camera time jitter or recorder time jitter. A similar noise source is generated from the interplay of patient absorption inhomogeneities and patient motion or image re-registration. Signal-to-noise ratios were measured for a variety of experimental conditions using subtracted digital images. Image-intensifier structure noise was shown to be a dominant noise source in unsubtracted images at medium to high radiation exposure levels. A total-system signal-to-noise ratio (SNR) of 750:1 was measured for an input exposure of 1 mR/frame at the image intensifier input. The effect of scattered radiation on subtracted image SNR was found to be greater than previously reported. The detail SNR was found to vary approximately as one plus the scatter degradation factor. Quantization error noise with 8-bit image processors (signal-to-noise ratio of 890:1) was shown to be of increased importance after recent improvements in TV cameras. The results of the analysis are useful both in the design of future digital radiography systems and the selection of optimum clinical techniques

  16. All Digital IQ Servo-System for CERN Linacs

    CERN Document Server

    Broere, J; Garoby, R; Rohlev, A; Serrano, J

    2004-01-01

    A VME based control system has been developed and built at CERN for the servo loops regulating the field in linac accelerating structures. It is an all-digital system built on a single VME card, providing digital detection, processing, and modulation. It is foreseen to be used, in different versions, for the needs of both present and future CERN hadron linacs. The first application will be in the energy ramping RF chain of the CERN Heavy Ion Linac (linac 3). Design principle and the experimental results are described.

  17. Development of DIGITEXαPlus digital angiographic system

    International Nuclear Information System (INIS)

    Imanishi, Tetsuo; Miura, Yusuke; Sasaki, Osamu; Furuyama, Makoto; Yasumi, Masayuki

    2001-01-01

    The functions required of digital angiographic (DA) systems have been noticeably changing with the recent popularization of the technique of interventional radiology (IVR) in the field of angiography. We have developed a new digital angiographic system, named the DIGITEXαPlus, which is designed to meet the requirements of the latest IVR technologies. The DIGITEXαPlus system is equipped with a high-performance one-million-pixel CCD camera, a newly developed F.P.O. (fluoro-power optimizer), and a contrast-priority radiography control system, which combine together to provide high quality of images both in fluoroscopy and in fluorography. In this new system, a low-dose pulsed fluoroscopy method, employed as standard, minimizes the X-ray doses to patients, and an image controller (IVR MASTER) of a joy stick type provides more diversified functions that its predecessors. These two features enhance the reliability, and simplifies the operation, of the IVR system as a whole. (author)

  18. Addressing the susceptibility of digital systems to electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1993-01-01

    This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Second, a verification and validation (V ampersand V) program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate acceptance should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation susceptibility attributable to EMI will be greatly reduced

  19. Digital System Reliability Test for the Evaluation of safety Critical Software of Digital Reactor Protection System

    Directory of Open Access Journals (Sweden)

    Hyun-Kook Shin

    2006-08-01

    Full Text Available A new Digital Reactor Protection System (DRPS based on VME bus Single Board Computer has been developed by KOPEC to prevent software Common Mode Failure(CMF inside digital system. The new DRPS has been proved to be an effective digital safety system to prevent CMF by Defense-in-Depth and Diversity (DID&D analysis. However, for practical use in Nuclear Power Plants, the performance test and the reliability test are essential for the digital system qualification. In this study, a single channel of DRPS prototype has been manufactured for the evaluation of DRPS capabilities. The integrated functional tests are performed and the system reliability is analyzed and tested. The results of reliability test show that the application software of DRPS has a very high reliability compared with the analog reactor protection systems.

  20. High Performance Low Cost Digitally Controlled Power Conversion Technology

    DEFF Research Database (Denmark)

    Jakobsen, Lars Tønnes

    2008-01-01

    in order to reduce the power consumption of servers and datacenters. The work presented in this thesis includes digital control methods for switch-mode converters implemented in microcontrollers, digital signal controllers and field programmable gate arrays. Microcontrollers are cheap devices that can...... be used for real-time control of switch-mode converters. Software design in the assembly language of the microcontroller is important because of the limited resources of the microcontroller. Microcontrollers are best suited for power electronics applications with low bandwidth requirements because...... the execution time of the software algorithm that realises the digital control law will constitute a considerable delay in the control loop. Digital signal controllers are powerful devices capable of performing arithmetic functions much faster than a microcontroller can. Digital signal controllers are well...

  1. Attribute-Based Digital Signature System

    NARCIS (Netherlands)

    Ibraimi, L.; Asim, Muhammad; Petkovic, M.

    2011-01-01

    An attribute-based digital signature system comprises a signature generation unit (1) for signing a message (m) by generating a signature (s) based on a user secret key (SK) associated with a set of user attributes, wherein the signature generation unit (1) is arranged for combining the user secret

  2. Summary of the preparation of methodology for digital system reliability analysis for PSA purposes

    International Nuclear Information System (INIS)

    Hustak, S.; Babic, P.

    2001-12-01

    The report is structured as follows: Specific features of and requirements for the digital part of NPP Instrumentation and Control (I and C) systems (Computer-controlled digital technologies and systems of the NPP I and C system; Specific types of digital technology failures and preventive provisions; Reliability requirements for the digital parts of I and C systems; Safety requirements for the digital parts of I and C systems; Defence-in-depth). Qualitative analyses of NPP I and C system reliability and safety (Introductory system analysis; Qualitative requirements for and proof of NPP I and C system reliability and safety). Quantitative reliability analyses of the digital parts of I and C systems (Selection of a suitable quantitative measure of digital system reliability; Selected qualitative and quantitative findings regarding digital system reliability; Use of relations among the occurrences of the various types of failure). Mathematical section in support of the calculation of the various types of indices (Boolean reliability models, Markovian reliability models). Example of digital system analysis (Description of a selected protective function and the relevant digital part of the I and C system; Functional chain examined, its components and fault tree). (P.A.)

  3. Field-Deployable Acoustic Digital Systems for Noise Measurement

    Science.gov (United States)

    Shams, Qamar A.; Wright, Kenneth D.; Lunsford, Charles B.; Smith, Charlie D.

    2000-01-01

    Langley Research Center (LaRC) has for years been a leader in field acoustic array measurement technique. Two field-deployable digital measurement systems have been developed to support acoustic research programs at LaRC. For several years, LaRC has used the Digital Acoustic Measurement System (DAMS) for measuring the acoustic noise levels from rotorcraft and tiltrotor aircraft. Recently, a second system called Remote Acquisition and Storage System (RASS) was developed and deployed for the first time in the field along with DAMS system for the Community Noise Flight Test using the NASA LaRC-757 aircraft during April, 2000. The test was performed at Airborne Airport in Wilmington, OH to validate predicted noise reduction benefits from alternative operational procedures. The test matrix was composed of various combinations of altitude, cutback power, and aircraft weight. The DAMS digitizes the acoustic inputs at the microphone site and can be located up to 2000 feet from the van which houses the acquisition, storage and analysis equipment. Digitized data from up to 10 microphones is recorded on a Jaz disk and is analyzed post-test by microcomputer system. The RASS digitizes and stores acoustic inputs at the microphone site that can be located up to three miles from the base station and can compose a 3 mile by 3 mile array of microphones. 16-bit digitized data from the microphones is stored on removable Jaz disk and is transferred through a high speed array to a very large high speed permanent storage device. Up to 30 microphones can be utilized in the array. System control and monitoring is accomplished via Radio Frequency (RF) link. This paper will present a detailed description of both systems, along with acoustic data analysis from both systems.

  4. Secure digital communication using controlled projective synchronisation of chaos

    International Nuclear Information System (INIS)

    Chee, C.Y.; Xu Daolin

    2005-01-01

    A new approach to chaos communication is proposed to encrypt digital information using controlled projective synchronisation. The scheme encrypts a binary sequence by manipulating the scaling feature of synchronisation from the coupled system. The transmitted signal therefore embeds only a single set of statistical properties. This prevents cryptanalysts from breaking the chaotic encryption scheme by using characteristic cryptanalysis that aims to detect switching of statistical properties in the intercepted information carrier signal. Pseudo-random switching key is incorporated into the scheme to masked out the deterministic nature of the underlying coupled system

  5. Virtual unit delay for digital frequency adaptive T/4 delay phase-locked loop system

    DEFF Research Database (Denmark)

    Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

    2016-01-01

    /processor with a fixed sampling rate considering the cost and complexity, where the number of unit delays that have been adopted should be an integer. For instance, in conventional digital control systems, a single-phase T/4 Delay Phase-Locked Loop (PLL) system takes 50 unit delays (i.e., in a 50-Hz system...... Delay PLL system should be done in its implementation. This process will result in performance degradation in the digital control system, as the exactly required number of delays is not realized. Hence, in this paper, a Virtual Unit Delay (VUD) has been proposed to address such challenges to the digital......Digital micro-controllers/processors enable the cost-effective control of grid-connected power converter systems in terms of system monitoring, signal processing (e.g., grid synchronization), control (e.g., grid current and voltage control), etc. Normally, the control is implemented in a micro-controller...

  6. [Telemedicine with digital video transport system].

    Science.gov (United States)

    Hahm, Joon Soo; Shimizu, Shuji; Nakashima, Naoki; Byun, Tae Jun; Lee, Hang Lak; Choi, Ho Soon; Ko, Yong; Lee, Kyeong Geun; Kim, Sun Il; Kim, Tae Eun; Yun, Jiwon; Park, Yong Jin

    2004-06-01

    The growth of technology based on internet protocol has affected on the informatics and automatic controls of medical fields. The aim of this study was to establish the telemedical educational system by developing the high quality image transfer using the DVTS (digital video transmission system) on the high-speed internet network. Using telemedicine, we were able to send surgical images not only to domestic areas but also to international area. Moreover, we could discuss the condition of surgical procedures in the operation room and seminar room. The Korean-Japan cable network (KJCN) was structured in the submarine between Busan and Fukuoka. On the other hand, the Korea advanced research network (KOREN) was used to connect between Busan and Seoul. To link the image between the Hanyang University Hospital in Seoul and Kyushu University Hospital in Japan, we started teleconference system and recorded image-streaming system with DVTS on the circumstance with IPv4 network. Two operative cases were transmitted successfully. We could keep enough bandwidth of 60 Mbps for two-line transmission. The quality of transmitted moving image had no frame loss with the rate 30 per second. The sound was also clear and the time delay was less than 0.3 sec. Our study has demonstrated the feasibility of domestic and international telemedicine. We have established an international medical network with high-quality video transmission over internet protocol. It is easy to perform, reliable, and also economical. Thus, it will be a promising tool in remote medicine for worldwide telemedical communication in the future.

  7. Polynomial Digital Control of a Series Equal Liquid Tanks

    Directory of Open Access Journals (Sweden)

    Bobála Vladimír

    2016-01-01

    Full Text Available Time-delays are mainly caused by the time required to transport mass, energy or information, but they can also be caused by processing time or accumulation. Typical examples of such processes are e.g. pumps, liquid storing tanks, distillation columns or some types of chemical reactors. In many cases time-delay is caused by the effect produced by the accumulation of a large number of low-order systems. Several industrial processes have the time-delay effect produced by the accumulation of a great number of low-order systems with the identical dynamic. The dynamic behavior of series these low-order systems is expressed by high-order system. One of possibilities of control of such processes is their approximation by low-order model with time-delay. The paper is focused on the design of the digital polynomial control of a set of equal liquid cylinder atmospheric tanks. The designed control algorithms are realized using the digital Smith Predictor (SP based on polynomial approach – by minimization of the Linear Quadratic (LQ criterion. The LQ criterion was combined with pole assignment.

  8. Testing Digital Electronic Protection Systems

    CERN Document Server

    Gabourin, S

    2011-01-01

    This paper outlines the core concepts and realisation of the Safe Machine Parameters Controller (SMPC) testbench, based on a VME crate and LabVIEW program. Its main goal is to ensure the correct function of the SMPC for the protection of the CERN accelerator complex. To achieve this, the tester has been built to replicate the machine environment and operation, in order to ensure that the chassis under test is completely exercised. The complexity of the task increases with the number of input combinations. This paper also outlines the benefits and weaknesses of developing a test suite independently of the hardware being tested, using the “V” approach.

  9. Reliability analysis of digital I and C systems at KAERI

    International Nuclear Information System (INIS)

    Kim, Man Cheol

    2013-01-01

    This paper provides an overview of the ongoing research activities on a reliability analysis of digital instrumentation and control (I and C) systems of nuclear power plants (NPPs) performed by the Korea Atomic Energy Research Institute (KAERI). The research activities include the development of a new safety-critical software reliability analysis method by integrating the advantages of existing software reliability analysis methods, a fault coverage estimation method based on fault injection experiments, and a new human reliability analysis method for computer-based main control rooms (MCRs) based on human performance data from the APR-1400 full-scope simulator. The research results are expected to be used to address various issues such as the licensing issues related to digital I and C probabilistic safety assessment (PSA) for advanced digital-based NPPs. (author)

  10. A digital intensity stabilization system for HeNe laser

    Science.gov (United States)

    Wei, Zhimeng; Lu, Guangfeng; Yang, Kaiyong; Long, Xingwu; Huang, Yun

    2012-02-01

    A digital intensity stabilization system for HeNe laser is developed. Based on a switching power IC to design laser power supply and a general purpose microcontroller to realize digital PID control, the system constructs a closed loop to stabilize the laser intensity by regulating its discharge current. The laser tube is made of glass ceramics and its integrated structure is steady enough to eliminate intensity fluctuations at high frequency and attenuates all intensity fluctuations, and this makes it easy to tune the control loop. The control loop between discharge current and photodiode voltage eliminates the long-term drifts. The intensity stability of the HeNe laser with this system is 0.014% over 12 h.

  11. MATLAB simulation for an experimental setup of digital feedback control

    International Nuclear Information System (INIS)

    Zheng Lifang; Liu Songqiang

    2005-01-01

    This paper describes the digital feedback simulation using MATLAB for an experimental accelerator control setup. By analyzing the plant characteristic in time-domain and frequency-domain, a guideline for design of digital filter and PID controller is derived. (authors)

  12. The development of digital oscilloscope control software in nuclear measurement

    International Nuclear Information System (INIS)

    Pu Minghui; Tian Geng; Li Xianyou

    2004-01-01

    This essay presents the development of an all-purpose digital oscilloscope control software on Windows 95/98 OS. The background and method are discussed in detail, together with the function and characteristics of the software. With the use of this software, a single PC can control several digital oscilloscopes. Solution of main problems encountered in the development is also discussed. (authors)

  13. Digital detection systems for projection radiography

    International Nuclear Information System (INIS)

    Schulz, R.F.

    2001-01-01

    This article gives a survey of digital X-ray detection systems for projection radiography. The different principles are compared and some general characteristics are derived. The basic conversion mechanisms in the absorption layers are described. The basic principles of solid state X-ray detectors and their general characteristics are elucidated as well as some similarities with detectors for computed tomography. Some important application and system aspects are considered. An outlook on further possible developments in this field is given. (orig.) [de

  14. [Analog gamma camera digitalization computer system].

    Science.gov (United States)

    Rojas, G M; Quintana, J C; Jer, J; Astudillo, S; Arenas, L; Araya, H

    2004-01-01

    Digitalization of analogue gamma cameras systems, using special acquisition boards in microcomputers and appropriate software for acquisition and processing of nuclear medicine images is described in detail. Microcomputer integrated systems interconnected by means of a Local Area Network (LAN) and connected to several gamma cameras have been implemented using specialized acquisition boards. The PIP software (Portable Image Processing) was installed on each microcomputer to acquire and preprocess the nuclear medicine images. A specialized image processing software has been designed and developed for these purposes. This software allows processing of each nuclear medicine exam, in a semiautomatic procedure, and recording of the results on radiological films. . A stable, flexible and inexpensive system which makes it possible to digitize, visualize, process, and print nuclear medicine images obtained from analogue gamma cameras was implemented in the Nuclear Medicine Division. Such a system yields higher quality images than those obtained with analogue cameras while keeping operating costs considerably lower (filming: 24.6%, fixing 48.2% and developing 26%.) Analogue gamma camera systems can be digitalized economically. This system makes it possible to obtain optimal clinical quality nuclear medicine images, to increase the acquisition and processing efficiency, and to reduce the steps involved in each exam.

  15. Virtual instrument for controlling and monitoring digitalized power supply in SSRF

    International Nuclear Information System (INIS)

    Tang Junlong; Chen Huanguang; Chinese Academy of Sciences, Beijing; Xu Ruinian; Shen Tianjian; Li Deming

    2006-01-01

    The Shanghai Synchrotron Radiation Facility (SSRF) needs extremely precise power supplies for their various magnets. A digital controller is being developed for the power converters of the SSRF power supply (PS). In the digital controller, a fully digital pulse-width modulator (PWM) directly controls the power unit insulated gate bipolar transistor (IGBT) of the PS. A program in LabVIEW language has been developed to control and monitor the digital PS via serial communication (RS232) from a PC and to modify its parameters as well. In this article, the software design of the virtual instrument for controlling and monitoring digitalized PS and its associated functions are described, and the essential elements of the program graphical main-VI and sub-VI source code are presented and explained. The communication protocol and the structure of the developed system are also included in this article. (authors)

  16. A technical survey on issues of the PSA of digital I and C system

    Energy Technology Data Exchange (ETDEWEB)

    Kang, H. G.; Sung, T. Y.; Eom, H. S.; Jeong, H. S.; Park, J. H.; Park, J. K.; Lee, K. Y.; Park, J. K

    2000-02-01

    This report describes the review results of the safety assessment and reliability analysis techniques of digital instrumentation and control (I and C) systems. The techniques are far from that of analog I and C systems because of the characteristics of digital systems. This report categorizes the current issues related to the safety assessment of digital I and C systems into three groups as follows: 1. The methodologies which could integrate the characteristics of hardware and that of software. 2. The methodologies which effectively represent safety improvement due to the fault-tolerant mechanisms embedded in digital I and C systems. 3. The methodologies which could effectively represent the phased-mission systems. (author)

  17. Essential Requirements for Digital Annotation Systems

    Directory of Open Access Journals (Sweden)

    ADRIANO, C. M.

    2012-06-01

    Full Text Available Digital annotation systems are usually based on partial scenarios and arbitrary requirements. Accidental and essential characteristics are usually mixed in non explicit models. Documents and annotations are linked together accidentally according to the current technology, allowing for the development of disposable prototypes, but not to the support of non-functional requirements such as extensibility, robustness and interactivity. In this paper we perform a careful analysis on the concept of annotation, studying the scenarios supported by digital annotation tools. We also derived essential requirements based on a classification of annotation systems applied to existing tools. The analysis performed and the proposed classification can be applied and extended to other type of collaborative systems.

  18. THE NOISE IMMUNITY OF THE DIGITAL DEMODULATOR MFM-AM SIGNAL USED IN DATA COMMUNICATIONS SYSTEMS OF AIR TRAFFIC CONTROL WITH AUTOMATIC DEPENDENT SURVEILLANCE AGAINST A NON-GAUSSIAN NOISE

    Directory of Open Access Journals (Sweden)

    A. L. Senyavskiy

    2015-01-01

    Full Text Available The article analyzes the robustness of the digital demodulator of the signal with the lowest frequency shift keying at a subcarrier frequency with respect to non-Gaussian interference type of atmospheric, industrial noise and interfering frequency -and phase-shift keyed signals. This type of demodulator is used for the transmission of navigation data in the systems of air traffic control with automatic dependent surveillance.

  19. Digital control in nuclear power plants

    International Nuclear Information System (INIS)

    Bouzon, B.

    1984-01-01

    This document presents the latest automatic control structures used in the programmable control systems of 13.00 MW nuclear power plants constructed by Electricite de France. The impact of this technological innovation goes beyond a straightforward design modification; in addition to the new range of processes made possible, it permits far-reaching changes in the working method employed at the design office and in the field. (author)

  20. Design for the human-machine interface of a digitalized reactor control-room

    International Nuclear Information System (INIS)

    Qu Ronghong; Zhang Liangju; Li Duo; Yu Hui

    2005-01-01

    Digitalized technology is implemented in the instrumentation and control system of an in-construction research reactor, which advances information display in both contents and styles in a nuclear reactor control-room, and greatly improves human-machine interface. In the design for a digitalized nuclear reactor control-room there are a series of new problems and technologies should be considered seriously. This paper mainly introduces the design for the digitalized control-room of the research nuclear reactor and covered topics include design principle of human-machine interface, organization and classification of interface graphics, technologies and principles based on human factors engineering and implemented in the graphics design. (authors)

  1. Process simulation in digital camera system

    Science.gov (United States)

    Toadere, Florin

    2012-06-01

    The goal of this paper is to simulate the functionality of a digital camera system. The simulations cover the conversion from light to numerical signal and the color processing and rendering. We consider the image acquisition system to be linear shift invariant and axial. The light propagation is orthogonal to the system. We use a spectral image processing algorithm in order to simulate the radiometric properties of a digital camera. In the algorithm we take into consideration the transmittances of the: light source, lenses, filters and the quantum efficiency of a CMOS (complementary metal oxide semiconductor) sensor. The optical part is characterized by a multiple convolution between the different points spread functions of the optical components. We use a Cooke triplet, the aperture, the light fall off and the optical part of the CMOS sensor. The electrical part consists of the: Bayer sampling, interpolation, signal to noise ratio, dynamic range, analog to digital conversion and JPG compression. We reconstruct the noisy blurred image by blending different light exposed images in order to reduce the photon shot noise, also we filter the fixed pattern noise and we sharpen the image. Then we have the color processing blocks: white balancing, color correction, gamma correction, and conversion from XYZ color space to RGB color space. For the reproduction of color we use an OLED (organic light emitting diode) monitor. The analysis can be useful to assist students and engineers in image quality evaluation and imaging system design. Many other configurations of blocks can be used in our analysis.

  2. Digital avionics systems - Overview of FAA/NASA/industry-wide briefing

    Science.gov (United States)

    Larsen, William E.; Carro, Anthony

    1986-01-01

    The effects of incorporating digital technology into the design of aircraft on the airworthiness criteria and certification procedures for aircraft are investigated. FAA research programs aimed at providing data for the functional assessment of aircraft which use digital systems for avionics and flight control functions are discussed. The need to establish testing, assurance assessment, and configuration management technologies to insure the reliability of digital systems is discussed; consideration is given to design verification, system performance/robustness, and validation technology.

  3. Options for Next Generation Digital Acquisition Systems

    CERN Document Server

    Boccardi, A

    2011-01-01

    Digital acquisition system designers have an always increasing number of options in terms of bus standards and digital signal processing hardware among which to choose. This allows for high flexibility but also opens the door to a proliferation of different architectures, potentially limiting the reusability and the design synergies among the various instrumentation groups. This contribution illustrates the design trends in some of the major institutes around the world with design examples including VME, PCI and TCA based modular systems using AMC and/or FMC mezzanines. Some examples of FPGA design practices aimed at increasing reusability of code will be mentioned together with some of the tools already available to designers to improve the information exchange and collaboration, like the Open Hardware Repository project.

  4. Experimental direct digital control of the power plant A1 reactor based on a modern control theory approach

    International Nuclear Information System (INIS)

    Karpeta, C.

    1979-01-01

    The objective of the project was to accumulate technical experience with application of modern control theory in nuclear power by carrying out a case study of an experimental direct digital control at the A1 reactor about its nominal steady state. The research has proved that slightly modified method of solution of the linear stochastic regulator problem can be successfully applied in design of digital control system of nuclear power reactors

  5. Digital subtraction radiography in the study of the lacrimal system

    International Nuclear Information System (INIS)

    Falaschi, F.; Pieri, L.; Perri, G.; Signorini, G.; Genovese Ebert, F.

    1988-01-01

    The authors emphasize the usefulness of digital dacrycystography (DCG), as compared with various current technoques. Utilizing a radiographic unit equipped with a video-fluoroscopic system and interfaced to a digital video-processor, several digitalized images are acquired before, during and after the injection of contrast medium. Final images are obtained by subtraction of suitable pairs of source frames. Twenty-six patients affected by epiphora have been examined so far. In 21 cases digital subtraction DCG allowed an accurate visualization of the lacrimal system; in the other five patients the amount of information was acceptable. This methodology allows the assessment of both the normal anatomy of the lacrimal passages and their pathological patterns, such as obstructions, stenoses, fistulas, chronic dacrycystites, lacrimal stones. The examination is easy and quick to perform, with no discomfort for the patient. Digital subtraction DCG proves thus to be a very valuable technique thanks to its possible electronic elaboration - i.e. the subtraction and the magnification of images - to its better contrast resolution, and to the possibility it yields of dynamic studies under radioscopic control

  6. Development and application of integrated digital I and C system in Japanese PWR plants

    International Nuclear Information System (INIS)

    Tominaga, M.

    1995-01-01

    The Integrated Digital Instrumentation and Control (I and C) System has been developed and applied to non-safety grade I and C systems in the latest 5 Japanese PWR plants in 1990's. Based on the experience in these plants, the Integrated Digital I and C System will be planned to apply also to safety grade I and C systems in Advanced PWR (APWR) as the overall application of digital technology. The basic design task has been just started for APWR which is to be in commercial operation in early 2000's and under the development about various issues of safety grade digital I and C systems. On the other hand, in conventional Japanese PWR plants,