WorldWideScience

Sample records for electricity system reliability

  1. Hawaii Electric System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Loose, Verne William [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Silva Monroy, Cesar Augusto [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2012-08-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers’ views of reliability “worth” and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers’ views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  2. Hawaii electric system reliability.

    Energy Technology Data Exchange (ETDEWEB)

    Silva Monroy, Cesar Augusto; Loose, Verne William

    2012-09-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers' views of reliability %E2%80%9Cworth%E2%80%9D and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers' views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  3. Reliability planning in distributed electric energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, E.

    1978-10-01

    The goal of this paper is to develop tools for technology evaluation that address questions involving the economics of large-scale systems. The kind of cost discussed usually involves some dynamic aspect of the energy system. In particular, such properties as flexibility, stability, and resilience are features of entire systems. Special attention must be paid to the question of reliability, i.e., availability on demand. The storage problem and the planning for reliability in utility systems are the subjects of this paper. The introductory chapter addresses preliminary definitions--reliability planning, uncertainty, resilience, and other sensitivities. The study focuses on the contrast between conventional power generation technologies with controllable output and intermittent resources such as wind and solar electric conversion devices. The system studied is a stylized representation of California conditions. Significant differences were found in reliability planning requirements (and therefore costs) for systems dominated by central station plants as opposed to those dominated by intermittent resource technologies. It is argued that existing hydroelectric facilities need re-optimization. These plants provide the only currently existing bulk power storage in electric energy systems. 38 references. (MCW)

  4. 77 FR 39858 - Revisions to Electric Reliability Organization Definition of Bulk Electric System and Rules of...

    Science.gov (United States)

    2012-07-05

    ... bulk electric system reliability through steady state power flow, and contain a transient stability... Commission 18 CFR Part 40 Revisions to Electric Reliability Organization Definition of Bulk Electric System... definition of ``bulk electric system'' developed by the North American Electric Reliability Corporation (NERC...

  5. 75 FR 72909 - Revision to Electric Reliability Organization Definition of Bulk Electric System

    Science.gov (United States)

    2010-11-26

    ... Bulk-Power System. See Rules Concerning Certification of the Electric Reliability Organization; and... Bulk-Power System in North America because it protects the reliability of the bulk electric system and... Electric Reliability Organization Definition of Bulk Electric System; Final Rule #0;#0;Federal Register...

  6. 78 FR 29209 - Revisions to Electric Reliability Organization Definition of Bulk Electric System and Rules of...

    Science.gov (United States)

    2013-05-17

    ... Commission 18 CFR Part 40 Revisions to Electric Reliability Organization Definition of Bulk Electric System... local distribution'' as set forth in the Federal Power Act (FPA). \\1\\ Revisions to Electric Reliability... Reliability Organization Definition of Bulk Electric System, Order No. 743, 133 FERC ] 61,150, at P 16 (2010...

  7. 76 FR 16263 - Revision to Electric Reliability Organization Definition of Bulk Electric System

    Science.gov (United States)

    2011-03-23

    ...; Order No. 743-A] Revision to Electric Reliability Organization Definition of Bulk Electric System AGENCY... certain provisions of the Final Rule. Order No. 743 directed the Electric Reliability Organization (ERO) to revise the definition of the term ``bulk electric system'' through the ERO's Reliability Standards...

  8. Improvement of standards on functional reliability of electric power systems

    International Nuclear Information System (INIS)

    Barinov, V.A.; Volkov, G.A.; Kalita, V.V.; Kogan, F.L.; Makarov, S.F.; Manevich, A.S.; Mogirev, V.V.; Sin'chugov, F.I.; Skopintsev, V.A.; Khvoshchinskaya, Z.G.

    1993-01-01

    Analysis of the most principal aspects of the existing standards and requirements on assuring safety and stability of electric power systems (EPS) and effective (reliable and economical) power supply of consumers is given. The reliability is determined as ability to accomplish the assigned functions. Basic recommendations on improving the standards regulating the safety and reliability of the NPP functioning are formulated

  9. FUNDAMENTALS OF RELIABILITY OF ELECTRIC POWER SYSTEM AND EQUIPMENT

    OpenAIRE

    Engr. Anumaka; Michael Chukwukadibia

    2011-01-01

    Today, the electric power system consists of complex interconnected network which are prone to different problems that militates against the reliability of the power system. Inadequate reliability in the power system causes problems such as high failure rate of power system installations and consumer equipment, transient and intransient faults, symmetrical faults etc. This paper provides an extensive review of the powers system and equipment reliability and related failure patterns in equipment.

  10. Reliability Electrical Power System of Hospital as Cold Standby System

    Directory of Open Access Journals (Sweden)

    Grabski Franciszek

    2016-07-01

    Full Text Available The probabilistic model of a hospital electrical power system consisting of mains, an emergency power system and the automatic transfer switch with the generator starter are discussed in this paper. The reliability model is semi-Markov process describing two different units renewable cold standby system and switch. The embedded Semi-Markov processes concept is applied for description of the system evolution. Time to failure of the system is represented by a random variable denoting the first passage time of the process from the given state to the subset of states. The appropriate theorems of the Semi-Markov processes theory allow us to evaluate the reliability function and some reliability characteristics.

  11. Reliability evaluation of deregulated electric power systems for planning applications

    International Nuclear Information System (INIS)

    Ehsani, A.; Ranjbar, A.M.; Jafari, A.; Fotuhi-Firuzabad, M.

    2008-01-01

    In a deregulated electric power utility industry in which a competitive electricity market can influence system reliability, market risks cannot be ignored. This paper (1) proposes an analytical probabilistic model for reliability evaluation of competitive electricity markets and (2) develops a methodology for incorporating the market reliability problem into HLII reliability studies. A Markov state space diagram is employed to evaluate the market reliability. Since the market is a continuously operated system, the concept of absorbing states is applied to it in order to evaluate the reliability. The market states are identified by using market performance indices and the transition rates are calculated by using historical data. The key point in the proposed method is the concept that the reliability level of a restructured electric power system can be calculated using the availability of the composite power system (HLII) and the reliability of the electricity market. Two case studies are carried out over Roy Billinton Test System (RBTS) to illustrate interesting features of the proposed methodology

  12. Reliability modeling of Clinch River breeder reactor electrical shutdown systems

    International Nuclear Information System (INIS)

    Schatz, R.A.; Duetsch, K.L.

    1974-01-01

    The initial simulation of the probabilistic properties of the Clinch River Breeder Reactor Plant (CRBRP) electrical shutdown systems is described. A model of the reliability (and availability) of the systems is presented utilizing Success State and continuous-time, discrete state Markov modeling techniques as significant elements of an overall reliability assessment process capable of demonstrating the achievement of program goals. This model is examined for its sensitivity to safe/unsafe failure rates, sybsystem redundant configurations, test and repair intervals, monitoring by reactor operators; and the control exercised over system reliability by design modifications and the selection of system operating characteristics. (U.S.)

  13. Influence of reliability of the relay protection to the whole reliability of electric power systems

    International Nuclear Information System (INIS)

    Stojanovski, Ljupcho I.

    2001-01-01

    The influence of the reliability of the elements of relay protection up today analyses of the reliability on electric power systems, very rare has been taken into consideration, in other words, in these analyses it is assumed that the reliability of the protection has value one. In this work an attempt is that through modelling of individual types of protection of the elements of high-voltage systems to make calculation to the influence of the reliability of the relay protection on the total reliability of the high-voltage systems.(Author)

  14. Applying reliability analysis to design electric power systems for More-electric aircraft

    Science.gov (United States)

    Zhang, Baozhu

    The More-Electric Aircraft (MEA) is a type of aircraft that replaces conventional hydraulic and pneumatic systems with electrically powered components. These changes have significantly challenged the aircraft electric power system design. This thesis investigates how reliability analysis can be applied to automatically generate system topologies for the MEA electric power system. We first use a traditional method of reliability block diagrams to analyze the reliability level on different system topologies. We next propose a new methodology in which system topologies, constrained by a set reliability level, are automatically generated. The path-set method is used for analysis. Finally, we interface these sets of system topologies with control synthesis tools to automatically create correct-by-construction control logic for the electric power system.

  15. Bayesian approach in the power electric systems study of reliability ...

    African Journals Online (AJOL)

    Keywords: Reliability - Power System - Bayes Theorem - Weibull Model - Probability. ... ensure a series of estimated parameter (failure rate, mean time to failure, function .... only on random variable r.v. describing the operating conditions: ..... Multivariate performance reliability prediction in real-time, Reliability Engineering.

  16. Bayesian approach in the power electric systems study of reliability ...

    African Journals Online (AJOL)

    Subsequently, Bayesian methodologies are framed in an ampler problem list, based on the definition of an opportune "vector of state" and of a vector describing the system performances, aiming to the definition and the calculation or the estimation of system reliability. The purpose of our work is to establish a useful model ...

  17. 75 FR 14097 - Revision to Electric Reliability Organization Definition of Bulk Electric System

    Science.gov (United States)

    2010-03-24

    ... electrical failure of a 138 kV motor operated switch on a 138 kV-13 kV transformer located in the ReliabilityFirst region resulted in the tripping of two transformers, one due to the electrical failure and the... Commission 18 CFR Part 40 [Docket No. RM09-18-000; 130 FERC ] 61,204] Revision to Electric Reliability...

  18. Reliability Assessment of Wind Farm Electrical System Based on a Probability Transfer Technique

    Directory of Open Access Journals (Sweden)

    Hejun Yang

    2018-03-01

    Full Text Available The electrical system of a wind farm has a significant influence on the wind farm reliability and electrical energy yield. The disconnect switch installed in an electrical system cannot only improve the operating flexibility, but also enhance the reliability for a wind farm. Therefore, this paper develops a probabilistic transfer technique for integrating the electrical topology structure, the isolation operation of disconnect switch, and stochastic failure of electrical equipment into the reliability assessment of wind farm electrical system. Firstly, as the traditional two-state reliability model of electrical equipment cannot consider the isolation operation, so the paper develops a three-state reliability model to replace the two-state model for incorporating the isolation operation. In addition, a proportion apportion technique is presented to evaluate the state probability. Secondly, this paper develops a probabilistic transfer technique based on the thoughts that through transfer the unreliability of electrical system to the energy transmission interruption of wind turbine generators (WTGs. Finally, some novel indices for describing the reliability of wind farm electrical system are designed, and the variance coefficient of the designed indices is used as a convergence criterion to determine the termination of the assessment process. The proposed technique is applied to the reliability assessment of a wind farm with the different topologies. The simulation results show that the proposed techniques are effective in practical applications.

  19. Industrial plant electrical systems: Simplicity, reliability, cost savings, redundancies

    International Nuclear Information System (INIS)

    Silvestri, A.; Tommazzolli, F.; Pavia Univ.

    1992-01-01

    This article represents a compact but complete design and construction manual for industrial plant electrical systems. It is to be used by design engineers having prior knowledge of local power supply routes and voltages and regards principally the optimum choice of internal distribution systems which can be radial or single, double ringed or with various network configurations, and with single or multiple supplies, and many or few redundancies. After giving guidelines on the choosing of these options, the manual deals with problematics relevant to suitable cable sizing. A cost benefit benefit analysis method is suggested for the choice of the number of redundancies. Recommendations are given for the choice of transformers, motorized equipment, switch boards and circuit breakers. Reference is made to Italian electrical safety and building codes

  20. Bulk electric system reliability evaluation incorporating wind power and demand side management

    Science.gov (United States)

    Huang, Dange

    Electric power systems are experiencing dramatic changes with respect to structure, operation and regulation and are facing increasing pressure due to environmental and societal constraints. Bulk electric system reliability is an important consideration in power system planning, design and operation particularly in the new competitive environment. A wide range of methods have been developed to perform bulk electric system reliability evaluation. Theoretically, sequential Monte Carlo simulation can include all aspects and contingencies in a power system and can be used to produce an informative set of reliability indices. It has become a practical and viable tool for large system reliability assessment technique due to the development of computing power and is used in the studies described in this thesis. The well-being approach used in this research provides the opportunity to integrate an accepted deterministic criterion into a probabilistic framework. This research work includes the investigation of important factors that impact bulk electric system adequacy evaluation and security constrained adequacy assessment using the well-being analysis framework. Load forecast uncertainty is an important consideration in an electrical power system. This research includes load forecast uncertainty considerations in bulk electric system reliability assessment and the effects on system, load point and well-being indices and reliability index probability distributions are examined. There has been increasing worldwide interest in the utilization of wind power as a renewable energy source over the last two decades due to enhanced public awareness of the environment. Increasing penetration of wind power has significant impacts on power system reliability, and security analyses become more uncertain due to the unpredictable nature of wind power. The effects of wind power additions in generating and bulk electric system reliability assessment considering site wind speed

  1. 78 FR 803 - Revisions to Electric Reliability Organization Definition of Bulk Electric System and Rules of...

    Science.gov (United States)

    2013-01-04

    ... Bulk 74. Electric System 1. Inclusion I1 (Transformers) 75. Commission Determination 80. 2. Inclusion... configurations are included in the bulk electric system. Inclusions: I1--Transformers with the primary terminal... bulk electric system. 15. NERC explained that inclusion I1 includes transformers with the primary...

  2. Small nuclear power reactor emergency electric power supply system reliability comparative analysis

    International Nuclear Information System (INIS)

    Bonfietti, Gerson

    2003-01-01

    This work presents an analysis of the reliability of the emergency power supply system, of a small size nuclear power reactor. Three different configurations are investigated and their reliability analyzed. The fault tree method is used as the main tool of analysis. The work includes a bibliographic review of emergency diesel generator reliability and a discussion of the design requirements applicable to emergency electrical systems. The influence of common cause failure influences is considered using the beta factor model. The operator action is considered using human failure probabilities. A parametric analysis shows the strong dependence between the reactor safety and the loss of offsite electric power supply. It is also shown that common cause failures can be a major contributor to the system reliability. (author)

  3. Assessing Changes in the Reliability of the U.S. Electric Power System

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Peter H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stanford Univ., CA (United States). Dept. of Physics; LaCommare, Kristina H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eto, Joseph H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sweeney, James L. [Stanford Univ., CA (United States)

    2015-08-01

    Over the past 15 years, the most well-publicized efforts to assess trends in U.S. electric power system reliability have focused only on a subset of all power interruption events (see, for example, Amin 2008 and Campbell 2012)—namely, only the very largest events, which trigger immediate emergency reporting to federal agencies and industry regulators. Anecdotally, these events are thought by many to represent no more than 10% of the power interruptions experienced annually by electricity consumers. Moreover, a review of these emergency reports has identified shortcomings in relying on these data as reliable sources for assessing trends, even with the reliability events they report (Fisher et al. 2012). Recent work has begun to address these limitations by examining trends in reliability data collected annually by electricity distribution companies (Eto et al. 2012). In principle, all power interruptions experienced by electricity customers, regardless of size, are recorded by the distribution utility. Moreover, distribution utilities have a long history of recording this information, often in response to mandates from state public utility commissions (Eto et al. 2006). Thus, studies that rely on reliability data collected by distribution utilities can, in principle, provide a more complete basis upon which to assess trends or changes in reliability over time.

  4. State Electricity Regulatory Policy and Distributed Resources: Distributed Resources and Electric System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Cowart, R.; Harrington, C.; Moskovitz, D.; Shirley, W.; Weston, F.; Sedano, R.

    2002-10-01

    Designing and implementing credit-based pilot programs for distributed resources distribution is a low-cost, low-risk opportunity to find out how these resources can help defer or avoid costly electric power system (utility grid) distribution upgrades. This report describes implementation options for deaveraged distribution credits and distributed resource development zones. Developing workable programs implementing these policies can dramatically increase the deployment of distributed resources in ways that benefit distributed resource vendors, users, and distribution utilities. This report is one in the State Electricity Regulatory Policy and Distributed Resources series developed under contract to NREL (see Annual Technical Status Report of the Regulatory Assistance Project: September 2000-September 2001, NREL/SR-560-32733). Other titles in this series are: (1) Accommodating Distributed Resources in Wholesale Markets, NREL/SR-560-32497; (2) Distributed Resources and Electric System Re liability, NREL/SR-560-32498; (3) Distribution System Cost Methodologies for Distributed Generation, NREL/SR-560-32500; (4) Distribution System Cost Methodologies for Distributed Generation Appendices, NREL/SR-560-32501.

  5. Electrical system design and reliability at Ontario Hydro nuclear generating stations

    Energy Technology Data Exchange (ETDEWEB)

    Royce, C. J. [Ontario Hydro, 700 University Avenue, Toronto, Ontario M5G 1X6 (Canada)

    1986-02-15

    This paper provides an overview of design practice and the predicted and actual reliability of electrical station service Systems at Ontario Nuclear Generating Stations. Operational experience and licensing changes have indicated the desirability of improving reliability in certain instances. For example, the requirement to start large emergency coolant injection pumps resulted in the turbine generator units in a multi-unit station being used as a back-up power supply. Results of reliability analyses are discussed. To mitigate the effects of common mode events Ontario Hydro adopted a 'two group' approach to the design of safety related Systems. This 'two group' approach is reviewed and a single fully environmentally qualified standby power supply is proposed for future use. (author)

  6. On reliability and maintenance modelling of ageing equipment in electric power systems

    International Nuclear Information System (INIS)

    Lindquist, Tommie

    2008-04-01

    Maintenance optimisation is essential to achieve cost-efficiency, availability and reliability of supply in electric power systems. The process of maintenance optimisation requires information about the costs of preventive and corrective maintenance, as well as the costs of failures borne by both electricity suppliers and customers. To calculate expected costs, information is needed about equipment reliability characteristics and the way in which maintenance affects equipment reliability. The aim of this Ph.D. work has been to develop equipment reliability models taking the effect of maintenance into account. The research has focussed on the interrelated areas of condition estimation, reliability modelling and maintenance modelling, which have been investigated in a number of case studies. In the area of condition estimation two methods to quantitatively estimate the condition of disconnector contacts have been developed, which utilise results from infrared thermography inspections and contact resistance measurements. The accuracy of these methods were investigated in two case studies. Reliability models have been developed and implemented for SF6 circuit-breakers, disconnector contacts and XLPE cables in three separate case studies. These models were formulated using both empirical and physical modelling approaches. To improve confidence in such models a Bayesian statistical method incorporating information from the equipment design process was also developed. This method was illustrated in a case study of SF6 circuit-breaker operating rods. Methods for quantifying the effect of maintenance on equipment condition and reliability have been investigated in case studies on disconnector contacts and SF6 circuit-breakers. The input required by these methods are condition measurements and historical failure and maintenance data, respectively. This research has demonstrated that the effect of maintenance on power system equipment may be quantified using available data

  7. Reliable electricity. The effects of system integration and cooperative measures to make it work

    International Nuclear Information System (INIS)

    Hagspiel, Simeon; Koeln Univ.

    2017-01-01

    We investigate the effects of system integration for reliability of supply in regional electricity systems along with cooperative measures to support it. Specifically, we set up a model to contrast the benefits from integration through statistical balancing (i.e., a positive externality) with the risk of cascading outages (a negative externality). The model is calibrated with a comprehensive dataset comprising 28 European countries on a high spatial and temporal resolution. We find that positive externalities from system integration prevail, and that cooperation is key to meet reliability targets efficiently. To enable efficient solutions in a non-marketed environment, we formulate the problem as a cooperative game and study different rules to allocate the positive and negative effects to individual countries. Strikingly, we find that without a mechanism, the integrated solution is unstable. In contrast, proper transfer payments can be found to make all countries better off in full integration, and the Nucleolus is identified as a particularly promising candidate. The rule could be used as a basis for compensation payments to support the successful integration and cooperation of electricity systems.

  8. Reliable electricity. The effects of system integration and cooperative measures to make it work

    Energy Technology Data Exchange (ETDEWEB)

    Hagspiel, Simeon [Koeln Univ. (Germany). Energiewirtschaftliches Inst.; Koeln Univ. (Germany). Dept. of Economics

    2017-12-15

    We investigate the effects of system integration for reliability of supply in regional electricity systems along with cooperative measures to support it. Specifically, we set up a model to contrast the benefits from integration through statistical balancing (i.e., a positive externality) with the risk of cascading outages (a negative externality). The model is calibrated with a comprehensive dataset comprising 28 European countries on a high spatial and temporal resolution. We find that positive externalities from system integration prevail, and that cooperation is key to meet reliability targets efficiently. To enable efficient solutions in a non-marketed environment, we formulate the problem as a cooperative game and study different rules to allocate the positive and negative effects to individual countries. Strikingly, we find that without a mechanism, the integrated solution is unstable. In contrast, proper transfer payments can be found to make all countries better off in full integration, and the Nucleolus is identified as a particularly promising candidate. The rule could be used as a basis for compensation payments to support the successful integration and cooperation of electricity systems.

  9. METHODS OF IMPROVING THE RELIABILITY OF THE CONTROL SYSTEM TRACTION POWER SUPPLY OF ELECTRIC TRANSPORT BASED ON AN EXPERT INFORMATION

    Directory of Open Access Journals (Sweden)

    O. O. Matusevych

    2009-03-01

    Full Text Available The author proposed the numerous methods of solving the multi-criterion task – increasing of reliability of control system on the basis of expert information. The information, which allows choosing thoughtfully the method of reliability increasing for a control system of electric transport, is considered.

  10. 76 FR 58101 - Electric Reliability Organization Interpretation of Transmission Operations Reliability Standard

    Science.gov (United States)

    2011-09-20

    ....C. Cir. 2009). \\4\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, FERC... for maintaining real and reactive power balance. \\14\\ Electric Reliability Organization Interpretation...; Order No. 753] Electric Reliability Organization Interpretation of Transmission Operations Reliability...

  11. Dynamic Self-Adaptive Reliability Control for Electric-Hydraulic Systems

    Directory of Open Access Journals (Sweden)

    Yi Wan

    2015-02-01

    Full Text Available The high-speed electric-hydraulic proportional control is a new development of the hydraulic control technique with high reliability, low cost, efficient energy, and easy maintenance; it is widely used in industrial manufacturing and production. However, there are still some unresolved challenges, the most notable being the requirements of high stability and real-time by the classical control algorithm due to its high nonlinear characteristics. We propose a dynamic self-adaptive mixed control method based on the least squares support vector machine (LSSVM and the genetic algorithm for high-speed electric-hydraulic proportional control systems in this paper; LSSVM is used to identify and adjust online a nonlinear electric-hydraulic proportional system, and the genetic algorithm is used to optimize the control law of the controlled system and dynamic self-adaptive internal model control and predictive control are implemented by using the mixed intelligent method. The internal model and the inverse control model are online adjusted together. At the same time, a time-dependent Hankel matrix is constructed based on sample data; thus finite dimensional solution can be optimized on finite dimensional space. The results of simulation experiments show that the dynamic characteristics are greatly improved by the mixed intelligent control strategy, and good tracking and high stability are met in condition of high frequency response.

  12. Risk-based methods for reliability investments in electric power distribution systems

    Energy Technology Data Exchange (ETDEWEB)

    Alvehag, Karin

    2011-07-01

    Society relies more and more on a continuous supply of electricity. However, while under investments in reliability lead to an unacceptable number of power interruptions, over investments result in too high costs for society. To give incentives for a socio economically optimal level of reliability, quality regulations have been adopted in many European countries. These quality regulations imply new financial risks for the distribution system operator (DSO) since poor reliability can reduce the allowed revenue for the DSO and compensation may have to be paid to affected customers. This thesis develops a method for evaluating the incentives for reliability investments implied by different quality regulation designs. The method can be used to investigate whether socio economically beneficial projects are also beneficial for a profit-maximizing DSO subject to a particular quality regulation design. To investigate which reinvestment projects are preferable for society and a DSO, risk-based methods are developed. With these methods, the probability of power interruptions and the consequences of these can be simulated. The consequences of interruptions for the DSO will to a large extent depend on the quality regulation. The consequences for the customers, and hence also society, will depend on factors such as the interruption duration and time of occurrence. The proposed risk-based methods consider extreme outage events in the risk assessments by incorporating the impact of severe weather, estimating the full probability distribution of the total reliability cost, and formulating a risk-averse strategy. Results from case studies performed show that quality regulation design has a significant impact on reinvestment project profitability for a DSO. In order to adequately capture the financial risk that the DSO is exposed to, detailed riskbased methods, such as the ones developed in this thesis, are needed. Furthermore, when making investment decisions, a risk

  13. Improving electrical power systems reliability through locally controlled distributed curtailable load

    Science.gov (United States)

    Dehbozorgi, Mohammad Reza

    2000-10-01

    Improvements in power system reliability have always been of interest to both power companies and customers. Since there are no sizable electrical energy storage elements in electrical power systems, the generated power should match the load demand at any given time. Failure to meet this balance may cause severe system problems, including loss of generation and system blackouts. This thesis proposes a methodology which can respond to either loss of generation or loss of load. It is based on switching of electric water heaters using power system frequency as the controlling signal. The proposed methodology encounters, and the thesis has addressed, the following associated problems. The controller must be interfaced with the existing thermostat control. When necessary to switch on loads, the water in the tank should not be overheated. Rapid switching of blocks of load, or chattering, has been considered. The contributions of the thesis are: (A) A system has been proposed which makes a significant portion of the distributed loads connected to a power system to behave in a predetermined manner to improve the power system response during disturbances. (B) The action of the proposed system is transparent to the customers. (C) The thesis proposes a simple analysis for determining the amount of such loads which might be switched and relates this amount to the size of the disturbances which can occur in the utility. (D) The proposed system acts without any formal communication links, solely using the embedded information present system-wide. (E) The methodology of the thesis proposes switching of water heater loads based on a simple, localized frequency set-point controller. The thesis has identified the consequent problem of rapid switching of distributed loads, which is referred to as chattering. (F) Two approaches have been proposed to reduce chattering to tolerable levels. (G) A frequency controller has been designed and built according to the specifications required to

  14. Analyzing the topological, electrical and reliability characteristics of a power transmission system for identifying its critical elements

    International Nuclear Information System (INIS)

    Zio, E.; Golea, L.R.

    2012-01-01

    The subject of this paper is the analysis of an electrical transmission system with the objective of identifying its most critical elements with respect to failures and attacks. The methodological approach undertaken is based on graph-theoretical (topological) network analysis. Four different perspectives of analysis are considered within the formalism of weighed networks, adding to the purely topological analysis of the system, the reliability and electrical characteristics of its components. In each phase of the analysis: i) a graph-theoretical representation is offered to highlight the structure of the most important system connections according to the particular characteristics examined (topological, reliability, electrical or electrical-reliability), ii) the classical degree index of a network node is extended to account for the different characteristics considered. The application of these concepts of analysis to an electrical transmission system of literature confirms the importance of different perspectives of analysis on such a critical infrastructure. - Highlights: ► We analyze a power system from topological, reliability and electrical perspectives. ► We rank critical components within a vulnerability assessment framework. ► We compute an extended degree to rank critical energy paths. ► We compare several analytical approaches and provide a table for choosing among them. ► We suggest network changes to increase the reliability of highly loaded energy paths.

  15. OPTIMIZATION OF THE RELIABILITY OF AGRICULTURAL CONSUMERS ELECTRICITY DISTRIBUTING AND SUPPLY SYSTEMS

    Directory of Open Access Journals (Sweden)

    Lupushor I.

    2007-12-01

    Full Text Available The problems of the optimization reliability in electrical networks of the different class of voltage have probabilistic nature, they discretely change and depend on the number of factors both definite and indefinite and have importance by selection of electric equipment, graph of development of electrical networks and voltage levels. The definition of the major factors, which have determining significance on their value and speed of their change allow to elaborate methods of their optimization and to elaborate effective methods of their growth limitation in electrical networks with the different class of voltage.

  16. RELIABILITY ANALYSIS OF THE ELECTRICAL POWER DISTRIBUTION SYSTEM TO SELECTED PORTIONS OF THE NUCLEAR HVAC SYSTEM

    International Nuclear Information System (INIS)

    Ramirez, N.

    2004-01-01

    A design requirement probability of 0.01 or less in a 4-hour period ensures that the nuclear heating, ventilation, and air-conditioning (HVAC) system in the primary confinement areas of the Dry Transfer Facilities (DTFs) and Fuel Handling Facility (FHF) is working during a Category 1 drop event involving commercial spent nuclear fuel (CSNF) assemblies (BSC 2004a , Section 5.1.1.48). This corresponds to an hourly HVAC failure rate of 2.5E-3 per hour or less, which is contributed to by two dominant causes: equipment failure and loss of electrical power. Meeting this minimum threshold ensures that a Category 1 initiating event followed by the failure of HVAC is a Category 2 event sequence. The two causes for the loss of electrical power include the loss of offsite power and the loss of onsite power distribution. Thus, in order to meet the threshold requirement aforementioned, the failure rate of mechanical equipment, loss of offsite power, and loss of onsite power distribution must be less than or equal to 2.5E-3 per hour for the nuclear HVAC system in the primary confinement areas of the DTFs and FHF. The loss of offsite power occurs at a frequency of 1.1E-5 per hour (BSC 2004a, Section 5.1.1.48). The purpose of this analysis is to determine the probability of occurrence of the unavailability of the nuclear HVAC system in the primary confinement areas of the DTFs and FHF due to loss of electrical power. In addition, this analysis provides insights on the contribution to the unavailability of the HVAC system due to equipment failure. The scope of this analysis is limited to finding the frequency of loss of electrical power to the nuclear HVAC system in the primary confinement areas of the DTFs and FHF

  17. Engineering of electrical systems of nuclear power stations for improved reliability

    International Nuclear Information System (INIS)

    Narasinga Rao, S.N.; Ramanathan, K.; Choudhary, N.N.

    1977-01-01

    Operational problems experienced in electrical systems/equipment of the Tarapur Atomic Power Station (TAPS) and the Rajasthan Atomic Power Station (RAPS) and their solutions are dealt in detail. This experience has led to new design concepts which are being introduced for improved reliability in design of the Madras Atomic Power Project (MAPP) and the Narora Atomic Power Project (NAPP). Saline pollution on switchyard equipments was the major problem of the TAPS due to its coastal location. Saline pollution resulted in flash over of insulators and failure of clamps. The problem was solved by suitable changes in insulators, conductors, transformers, switches and arranging portable live line washing of the switchyard equipment. In MAPP which is also located on coast, an indoor switchyard is built. NAPP is located in a seismic zone, therefore, all equipment is specified for appropriate seismic duty. Various other improvements are described. (M.G.B.)

  18. INCREASED RELIABILITY OF ELECTRIC BLASTING

    OpenAIRE

    Kashuba, Oleh Ivanovych; Skliarov, L I; Skliarov, A L

    2017-01-01

    The problems of improving reliability of an electric blasting method using electric detonators with nichrome filament bridges. It was revealed that in the calculation of the total resistance of the explosive network it is necessary to increase to 24% of the nominal value

  19. 18-month outlook : an assessment of the reliability of the Ontario Electricity System

    International Nuclear Information System (INIS)

    2005-01-01

    This paper provides an 18 month forecast of the Ontario electricity system, as well as an outline of activities and recent developments relating to the issue of reliability. An additional aim of the paper was to identify potentially adverse conditions that may require adjustment or coordination of maintenance plans for generation and transmission equipment. Requests for proposals (RFPs) for renewable generation within the specified time-frame were also discussed, as well as the return to service of Ontario Power Generation's Pickering Unit 1. Reduced reserve levels for the summer of 2005 were anticipated, and details of forecasted peak demand, generator maintenance, new generation and price-responsive demand adjustments and forced outage rates were presented. It was suggested that adequate market mechanisms were in place to manage reserve levels. Developments concerning the new Parkway Transformer station were reviewed. A resource outlook was provided. Available resources were expected to exceed planning requirements with the exception of 6 weeks in the summer of 2005. A projected capacity increase was also anticipated, due to the return of Pickering 1 and an additional 515 MW in the fall of 2005. Price-responsive demands were forecasted to exceed 650 MW due to increases in dispatchable load. It was suggested that in order to ensure power demand during peak periods, imports may be required under extreme weather conditions, combined with the possible deferral or cancellation of generation maintenance. Transmission impacts due to shutdowns were discussed. Voltage system requirements were reviewed, along with details of the installation of additional shunt capacitors and transformer controls. The electricity market was reviewed in the context of current overall economic conditions. Data forecasting normal peak demand was presented for the entire outlook period. 19 tabs., 10 figs

  20. Multidisciplinary System Reliability Analysis

    Science.gov (United States)

    Mahadevan, Sankaran; Han, Song; Chamis, Christos C. (Technical Monitor)

    2001-01-01

    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code, developed under the leadership of NASA Glenn Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multidisciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  1. 76 FR 73608 - Reliability Technical Conference, North American Electric Reliability Corporation, Public Service...

    Science.gov (United States)

    2011-11-29

    ... or municipal authority play in forming your bulk power system reliability plans? b. Do you support..., North American Electric Reliability Corporation (NERC) Nick Akins, CEO of American Electric Power (AEP..., EL11-62-000] Reliability Technical Conference, North American Electric Reliability Corporation, Public...

  2. An assessment of the reliability of the Ontario electricity system : 18-month outlook from April 2004 to September 2005

    International Nuclear Information System (INIS)

    2004-01-01

    This report presents a resource assessment by the Independent Electricity Market Operator (IMO) for the 18-month period from April 2004 to September 2005. It is based on the IMO's forecast of electricity demand. The information was provided by power generators in Ontario. The outlook for the electricity system has improved due to the return to service of 3 nuclear units and the addition of more than 700 MW of generation. The return to service of the nuclear units has decreased Ontario's reliance on imports to help meet energy demand in the province. The shutdown of 1150 MW of coal-fired generation at Lakeview Thermal Generating Station in Mississauga emphasizes the importance of improving transmission and generation capacity in the Toronto area. This report also includes updated values for existing resource scenarios and planned resource scenarios. The reliability of Ontario's transmission system was also assessed along with the adequacy of the existing resource to meet the forecast demand. The existing installed generation resources include 5 nuclear stations generating 10,831 MW of electricity, 5 coal stations generating 7,564 MW of electricity, 22 oil and gas fired stations generating 4,364 MW of electricity, 61 hydroelectric stations generating 7,676 MW of electricity, and 2 other stations generating 66 MW of electricity. Although the existing resource scenario is better than in previous reports, imports will be required under extreme weather conditions to help meet electricity demand in Ontario during peak periods. 21 tabs., 10 figs

  3. Systems reliability/structural reliability

    International Nuclear Information System (INIS)

    Green, A.E.

    1980-01-01

    The question of reliability technology using quantified techniques is considered for systems and structures. Systems reliability analysis has progressed to a viable and proven methodology whereas this has yet to be fully achieved for large scale structures. Structural loading variants over the half-time of the plant are considered to be more difficult to analyse than for systems, even though a relatively crude model may be a necessary starting point. Various reliability characteristics and environmental conditions are considered which enter this problem. The rare event situation is briefly mentioned together with aspects of proof testing and normal and upset loading conditions. (orig.)

  4. 18 CFR 39.3 - Electric Reliability Organization certification.

    Science.gov (United States)

    2010-04-01

    ... operators of the Bulk-Power System, and other interested parties for improvement of the Electric Reliability... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Electric Reliability..., Reliability Standards that provide for an adequate level of reliability of the Bulk-Power System, and (2) Has...

  5. Consortium for Electric Reliability Technology Solutions Grid of the Future White Paper on Review of Recent Reliability Issues and Systems Events

    Energy Technology Data Exchange (ETDEWEB)

    Hauer, John F.; Dagle, Jeffery E.

    1999-12-01

    This report is one of six reports developed under the U.S. Department of Energy (DOE) program in Power System Integration and Reliability (PSIR). The objective of this report is to review, analyze, and evaluate critical reliability issues demonstrated by recent disturbance events in the North America power system. Eleven major disturbances are examined, most occurring in this decade. The strategic challenge is that the pattern of technical need has persisted for a long period of time. For more than a decade, anticipation of market deregulation has been a major disincentive to new investments in system capacity. It has also inspired reduced maintenance of existing assets. A massive infusion of better technology is emerging as the final option to continue reliable electrical services. If an investment in better technology will not be made in a timely manner, then North America should plan its adjustments to a very different level of electrical service. It is apparent that technical operations staff among the utilities can be very effective at marshaling their forces in the immediate aftermath of a system emergency, and that serious disturbances often lead to improved mechanisms for coordinated operation. It is not at all apparent that such efforts can be sustained through voluntary reliability organizations in which utility personnel external to those organizations do most of the technical work. The eastern interconnection shows several situations in which much of the technical support has migrated from the utilities to the Independent System Operator (ISO), and the ISO staffs or shares staff with the regional reliability council. This process may be a natural and very positive consequence of utility restructuring. If so, the process should be expedited in regions where it is less advanced.

  6. 76 FR 23171 - Electric Reliability Organization Interpretations of Interconnection Reliability Operations and...

    Science.gov (United States)

    2011-04-26

    ... Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats. & Regs. ] 31,242, order on reh'g...-Power System reliability may request an interpretation of a Reliability Standard.\\7\\ The ERO's standards... information in its reliability assessments. The Reliability Coordinator must monitor Bulk Electric System...

  7. 76 FR 66055 - North American Electric Reliability Corporation; Order Approving Interpretation of Reliability...

    Science.gov (United States)

    2011-10-25

    ...\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats. & Regs. ] 31,242... materially affected'' by Bulk-Power System reliability may request an interpretation of a Reliability... Electric Reliability Corporation; Order Approving Interpretation of Reliability Standard; Before...

  8. The impact of faulty response of overload protection systems on the reliability of electricity supply

    International Nuclear Information System (INIS)

    Schweigert, J.; Schnuerer, G.

    1988-01-01

    Protection equipment of the engineered safety system which is to prevent the triggering of actions via signals from the reactor protection system is to be made so reliable that it has no impact on the non-availability of the supplied systems. Design and functional mode of the various overload protection equipment and the relevant switching device and combinations are explained together with the requirements such as choice, design, and adjustment of the protection equipment, followed by a survey of possible causes of faulty response of overload protection device and of the means and measures available for improvement. The now presented version of September 1987 of the 'overload protection report deals basically with all main topics of the Juli 1985 version, but has been updated and extended by material taking into account practice-oriented data on the new developments in convoy power plant design. (orig./HP) [de

  9. Space Station Freedom power - A reliability, availability, and maintainability assessment of the proposed Space Station Freedom electric power system

    Science.gov (United States)

    Turnquist, S. R.; Twombly, M.; Hoffman, D.

    1989-01-01

    A preliminary reliability, availability, and maintainability (RAM) analysis of the proposed Space Station Freedom electric power system (EPS) was performed using the unit reliability, availability, and maintainability (UNIRAM) analysis methodology. Orbital replacement units (ORUs) having the most significant impact on EPS availability measures were identified. Also, the sensitivity of the EPS to variations in ORU RAM data was evaluated for each ORU. Estimates were made of average EPS power output levels and availability of power to the core area of the space station. The results of assessments of the availability of EPS power and power to load distribution points in the space stations are given. Some highlights of continuing studies being performed to understand EPS availability considerations are presented.

  10. Innovations in power systems reliability

    CERN Document Server

    Santora, Albert H; Vaccaro, Alfredo

    2011-01-01

    Electrical grids are among the world's most reliable systems, yet they still face a host of issues, from aging infrastructure to questions of resource distribution. Here is a comprehensive and systematic approach to tackling these contemporary challenges.

  11. 76 FR 66057 - North American Electric Reliability Corporation; Order Approving Regional Reliability Standard

    Science.gov (United States)

    2011-10-25

    ... Reliability Standard that is necessitated by a physical difference in the Bulk-Power System.\\7\\ \\7\\ Order No... Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats. & Regs. ] 31,242, order on reh'g... electric system event analyses and thereby improve system reliability by promoting improved system design...

  12. 76 FR 23222 - Electric Reliability Organization Interpretation of Transmission Operations Reliability

    Science.gov (United States)

    2011-04-26

    ....3d 1342 (DC Cir. 2009). \\5\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693... Reliability Standards for the Bulk-Power System. Action: FERC-725A. OMB Control No.: 1902-0244. Respondents...] Electric Reliability Organization Interpretation of Transmission Operations Reliability AGENCY: Federal...

  13. Innovative protection and control systems for a reliable and secure operation of electrical transmission systems; Innovative Schutz- und Leitsysteme zur zuverlaessigen und sicheren elektrischen Energieuebertragung

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Sven C.; Kubis, Adreas; Rehtanz, Christian [Technische Univ. Dortmund (Germany). Inst. fuer Energiesysteme, Energieeffizienz und Energiewirtschaft (ie3); Brato, Sebastian; Goetze, Juergen [Technische Univ. Dortmund (Germany). Arbeitsgebiet Datentechnik

    2012-07-01

    The integration of European electricity markets as well as the increasing power feed-in by renewable energy sources pose new challenges to the operation of electrical transmission systems. Modern protection and control systems based on wide-area information can substantially contribute to a reliable and secure system operation even against the background of future demands. In this paper research advances regarding new applications for wide-area monitoring, protection and control as well as an integrated simulation for power and ICT systems are presented that have been developed in the course of DFG research unit FOR1511 at TU Dortmund. (orig.)

  14. System Reliability Engineering

    International Nuclear Information System (INIS)

    Lim, Tae Jin

    2005-02-01

    This book tells of reliability engineering, which includes quality and reliability, reliability data, importance of reliability engineering, reliability and measure, the poisson process like goodness of fit test and the poisson arrival model, reliability estimation like exponential distribution, reliability of systems, availability, preventive maintenance such as replacement policies, minimal repair policy, shock models, spares, group maintenance and periodic inspection, analysis of common cause failure, and analysis model of repair effect.

  15. 75 FR 71625 - System Restoration Reliability Standards

    Science.gov (United States)

    2010-11-24

    ... to start operating and delivering electric power without assistance from the electric system... and system restoration and reporting following disturbances. \\3\\ North American Electric Reliability... Reliability Standards for the Bulk-Power System and determined that the proposed requirements are necessary to...

  16. 78 FR 41339 - Electric Reliability Organization Proposal To Retire Requirements in Reliability Standards

    Science.gov (United States)

    2013-07-10

    ...] Electric Reliability Organization Proposal To Retire Requirements in Reliability Standards AGENCY: Federal... Reliability Standards identified by the North American Electric Reliability Corporation (NERC), the Commission-certified Electric Reliability Organization. FOR FURTHER INFORMATION CONTACT: Kevin Ryan (Legal Information...

  17. Demand Response Application forReliability Enhancement in Electricity Market

    OpenAIRE

    Romera Pérez, Javier

    2015-01-01

    The term reliability is related with the adequacy and security during operation of theelectric power system, supplying the electricity demand over time and saving thepossible contingencies because every inhabitant needs to be supplied with electricity intheir day to day. Operating the system in this way entails spending money. The first partof the project is going to be an analysis of the reliability and the economic impact of it.During the last decade, electric utilities and companies had be...

  18. Reliable computer systems.

    Science.gov (United States)

    Wear, L L; Pinkert, J R

    1993-11-01

    In this article, we looked at some decisions that apply to the design of reliable computer systems. We began with a discussion of several terms such as testability, then described some systems that call for highly reliable hardware and software. The article concluded with a discussion of methods that can be used to achieve higher reliability in computer systems. Reliability and fault tolerance in computers probably will continue to grow in importance. As more and more systems are computerized, people will want assurances about the reliability of these systems, and their ability to work properly even when sub-systems fail.

  19. Reliability Evaluation for Optimizing Electricity Supply in a Developing Country

    Directory of Open Access Journals (Sweden)

    Mark Ndubuka NWOHU

    2007-09-01

    Full Text Available The reliability standards for electricity supply in a developing country, like Nigeria, have to be determined on past engineering principles and practice. Because of the high demand of electrical power due to rapid development, industrialization and rural electrification; the economic, social and political climate in which the electric power supply industry now operates should be critically viewed to ensure that the production of electrical power should be augmented and remain uninterrupted. This paper presents an economic framework that can be used to optimize electric power system reliability. Finally the cost models are investigated to take into account the economic analysis of system reliability, which can be periodically updated to improve overall reliability of electric power system.

  20. Alberta's electricity policy framework : competitive, reliable, sustainable

    International Nuclear Information System (INIS)

    2005-01-01

    This paper described public policies in Alberta that are implemented to create an electric power industry that is competitive, reliable and sustainable. The success of Alberta's competitive electric market framework can be attributed to new investment in the industry along with new players participating in the electricity market. The Alberta Department of Energy is committed to a competitive wholesale market model and to competitively-priced electricity. The Alberta Energy and Utilities Board supports the development of Alberta's vast resource base and facilitates power generation development and support through transmission development and an interconnected transmission system. A wholesale market Policy Task Force was established in 2005 to review the progress in Alberta's electric market design and its competitive retail market. This paper outlines a policy framework which addresses design of the regulated rate option post July 1, 2006; short-term adequacy; and long-term adequacy. Other inter-related market issues were also discussed, such as operating reserves market, transmission services, interties, demand response, balancing pool assets, credit, market power mitigation, and wind generation. It is expected that the recommendations in this paper will be implemented as quickly as possible following amendments to regulations or ISO rules. tabs., figs.

  1. INCREASING RELIABILITY OF STEPPED AUTOMATIC STARTING AND RHEOSTAT BREAKING SYSTEM OF ELECTRIC TRAINS ER9T AND EPL9T

    Directory of Open Access Journals (Sweden)

    N. H. Visin

    2010-06-01

    Full Text Available The article examines transitional processes in the power circuit of tractive motors and their influence on the work of stepped automatic starting of electric trains ER9T and EPL9T. The recommendations for increasing the reliability of operation of multiple-unit rolling stock are proposed.

  2. Will British weather provide reliable electricity?

    International Nuclear Information System (INIS)

    Oswald, James; Raine, Mike; Ashraf-Ball, Hezlin

    2008-01-01

    There has been much academic debate on the ability of wind to provide a reliable electricity supply. The model presented here calculates the hourly power delivery of 25 GW of wind turbines distributed across Britain's grid, and assesses power delivery volatility and the implications for individual generators on the system. Met Office hourly wind speed data are used to determine power output and are calibrated using Ofgem's published wind output records. There are two main results. First, the model suggests that power swings of 70% within 12 h are to be expected in winter, and will require individual generators to go on or off line frequently, thereby reducing the utilisation and reliability of large centralised plants. These reductions will lead to increases in the cost of electricity and reductions in potential carbon savings. Secondly, it is shown that electricity demand in Britain can reach its annual peak with a simultaneous demise of wind power in Britain and neighbouring countries to very low levels. This significantly undermines the case for connecting the UK transmission grid to neighbouring grids. Recommendations are made for improving 'cost of wind' calculations. The authors are grateful for the sponsorship provided by The Renewable Energy Foundation

  3. Evaluation of the reliability of electric power transmission systems; Evaluacion de confiabilidad de sistemas de transmision de energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Vega Ortiz, Miguel

    1989-07-01

    In this thesis it is attacked the problem of Reliability Evaluation of the Electrical Power Transmission Systems for aims of its integral planning. Once described the problem the indexes that measure the electric power systems reliability are presented. Later the methods to evaluate the transmission nets, such as the Contingencies Enumeration, the Monte Carlo, the one of Markov and the methods for complex systems such as the Minimum Interruptions, are described. This last one is widely developed for the advantages that its application presents in the planning of large and complex networks. The method of minimum interruptions consists of two big steps: To determine the minimum interruptions for the load points and to calculate the reliability indexes in base of the minimum interruptions. The conventional algorithms for the determination of minimum interruptions consider a problem for each load point in an independent form going through a determination of minimum tracks. In this type of algorithms the CPU time and the space in memory required grow exponentially for the case of large transmission systems, which represents a strong restriction for its application. In order to solve this problem a methodology was established in which the system is modeled by means of a grapho and the minimum interruptions are determined with an algorithm based on the construction of cycles in the dual grapho. With these interruptions the connectivity and the capacity of the network is evaluated, obtaining the reliability indexes for each bus and the system. These indexes are calculated with the equivalent representation for complex systems of series parallel connections defined by the minimum interruptions. One of the fundamental objectives in this study is to integrate the reliability to the planning process, with the concept of the expected value of the non-supplied energy and its penalty cost. In order to demonstrate the capacity, effectiveness and rapidity of the new implemented

  4. LED system reliability

    NARCIS (Netherlands)

    Driel, W.D. van; Yuan, C.A.; Koh, S.; Zhang, G.Q.

    2011-01-01

    This paper presents our effort to predict the system reliability of Solid State Lighting (SSL) applications. A SSL system is composed of a LED engine with micro-electronic driver(s) that supplies power to the optic design. Knowledge of system level reliability is not only a challenging scientific

  5. Reliability risks during the transition to competitive electricity markets

    International Nuclear Information System (INIS)

    Hughes, J.P.

    2005-01-01

    The Electricity Consumers Resource Council (ELCON) is a U.S. association representing industrial consumers of electricity, and is a long-standing advocate of competition in the electric power industry. However, because a reliable grid is necessary to support competitive wholesale markets, ELCON believes that the transmission system is an essential facility that must remain regulated. The initiatives discussed in this white paper represent significant steps that the National Electric Reliability Council (NERC) and the industry have taken to improve reliability in a competitive and restructured electric industry. Strategic manoeuvres of incumbent utilities to maintain market share were evaluated, as well as discrimination against potential competitors. It was suggested that, occasionally, indecisive federal policies have been taken advantage of by utilities. The unintended consequences of state restructuring policies that allow utilities to over-earn their revenue requirements were reviewed. NERC reliability standards will remain unenforceable until a new Electricity Reliability Organization has been certified. Flawed market designs and inadequate market power mitigation, as well as the financial distress of merchant generators, pose considerable risks. It was suggested that these risks could trigger transmission loading relief incidents, local outages or widespread outages. In the absence of mandatory reliability standards with penalties, and complementary market rules for mitigating generation and transmission market power, economic incentives will encourage other forms of opportunistic behavior that may be the root cause of other outages. Public concern regarding these risks to grid reliability may result in lost public support for competitive electricity markets. Proposed solutions include the certification of a new Electric Reliability Organization to establish and enforce mandatory reliability standards, and granting the Federal Energy Regulatory Commission

  6. Integrated system reliability analysis

    DEFF Research Database (Denmark)

    Gintautas, Tomas; Sørensen, John Dalsgaard

    Specific targets: 1) The report shall describe the state of the art of reliability and risk-based assessment of wind turbine components. 2) Development of methodology for reliability and risk-based assessment of the wind turbine at system level. 3) Describe quantitative and qualitative measures...

  7. Reliability of electronic systems

    International Nuclear Information System (INIS)

    Roca, Jose L.

    2001-01-01

    Reliability techniques have been developed subsequently as a need of the diverse engineering disciplines, nevertheless they are not few those that think they have been work a lot on reliability before the same word was used in the current context. Military, space and nuclear industries were the first ones that have been involved in this topic, however not only in these environments it is that it has been carried out this small great revolution in benefit of the increase of the reliability figures of the products of those industries, but rather it has extended to the whole industry. The fact of the massive production, characteristic of the current industries, drove four decades ago, to the fall of the reliability of its products, on one hand, because the massively itself and, for other, to the recently discovered and even not stabilized industrial techniques. Industry should be changed according to those two new requirements, creating products of medium complexity and assuring an enough reliability appropriated to production costs and controls. Reliability began to be integral part of the manufactured product. Facing this philosophy, the book describes reliability techniques applied to electronics systems and provides a coherent and rigorous framework for these diverse activities providing a unifying scientific basis for the entire subject. It consists of eight chapters plus a lot of statistical tables and an extensive annotated bibliography. Chapters embrace the following topics: 1- Introduction to Reliability; 2- Basic Mathematical Concepts; 3- Catastrophic Failure Models; 4-Parametric Failure Models; 5- Systems Reliability; 6- Reliability in Design and Project; 7- Reliability Tests; 8- Software Reliability. This book is in Spanish language and has a potentially diverse audience as a text book from academic to industrial courses. (author)

  8. Distribution-level electricity reliability: Temporal trends using statistical analysis

    International Nuclear Information System (INIS)

    Eto, Joseph H.; LaCommare, Kristina H.; Larsen, Peter; Todd, Annika; Fisher, Emily

    2012-01-01

    This paper helps to address the lack of comprehensive, national-scale information on the reliability of the U.S. electric power system by assessing trends in U.S. electricity reliability based on the information reported by the electric utilities on power interruptions experienced by their customers. The research analyzes up to 10 years of electricity reliability information collected from 155 U.S. electric utilities, which together account for roughly 50% of total U.S. electricity sales. We find that reported annual average duration and annual average frequency of power interruptions have been increasing over time at a rate of approximately 2% annually. We find that, independent of this trend, installation or upgrade of an automated outage management system is correlated with an increase in the reported annual average duration of power interruptions. We also find that reliance on IEEE Standard 1366-2003 is correlated with higher reported reliability compared to reported reliability not using the IEEE standard. However, we caution that we cannot attribute reliance on the IEEE standard as having caused or led to higher reported reliability because we could not separate the effect of reliance on the IEEE standard from other utility-specific factors that may be correlated with reliance on the IEEE standard. - Highlights: ► We assess trends in electricity reliability based on the information reported by the electric utilities. ► We use rigorous statistical techniques to account for utility-specific differences. ► We find modest declines in reliability analyzing interruption duration and frequency experienced by utility customers. ► Installation or upgrade of an OMS is correlated to an increase in reported duration of power interruptions. ► We find reliance in IEEE Standard 1366 is correlated with higher reported reliability.

  9. North American Electric Reliability Council (NERC) Reliability Coordinators

    Data.gov (United States)

    Department of Homeland Security — ERC is an international regulatory authority that works to improve the reliability of the bulk power system in North America. NERC works with many different regional...

  10. CERTS: Consortium for Electric Reliability Technology Solutions - Research Highlights

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph

    2003-07-30

    Historically, the U.S. electric power industry was vertically integrated, and utilities were responsible for system planning, operations, and reliability management. As the nation moves to a competitive market structure, these functions have been disaggregated, and no single entity is responsible for reliability management. As a result, new tools, technologies, systems, and management processes are needed to manage the reliability of the electricity grid. However, a number of simultaneous trends prevent electricity market participants from pursuing development of these reliability tools: utilities are preoccupied with restructuring their businesses, research funding has declined, and the formation of Independent System Operators (ISOs) and Regional Transmission Organizations (RTOs) to operate the grid means that control of transmission assets is separate from ownership of these assets; at the same time, business uncertainty, and changing regulatory policies have created a climate in which needed investment for transmission infrastructure and tools for reliability management has dried up. To address the resulting emerging gaps in reliability R&D, CERTS has undertaken much-needed public interest research on reliability technologies for the electricity grid. CERTS' vision is to: (1) Transform the electricity grid into an intelligent network that can sense and respond automatically to changing flows of power and emerging problems; (2) Enhance reliability management through market mechanisms, including transparency of real-time information on the status of the grid; (3) Empower customers to manage their energy use and reliability needs in response to real-time market price signals; and (4) Seamlessly integrate distributed technologies--including those for generation, storage, controls, and communications--to support the reliability needs of both the grid and individual customers.

  11. A case study review of technical and technology issues for transition of a utility load management program to provide system reliability resources in restructured electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    Weller, G.H.

    2001-07-15

    Utility load management programs--including direct load control and interruptible load programs--were employed by utilities in the past as system reliability resources. With electricity industry restructuring, the context for these programs has changed; the market that was once controlled by vertically integrated utilities has become competitive, raising the question: can existing load management programs be modified so that they can effectively participate in competitive energy markets? In the short run, modified and/or improved operation of load management programs may be the most effective form of demand-side response available to the electricity system today. However, in light of recent technological advances in metering, communication, and load control, utility load management programs must be carefully reviewed in order to determine appropriate investments to support this transition. This report investigates the feasibility of and options for modifying an existing utility load management system so that it might provide reliability services (i.e. ancillary services) in the competitive markets that have resulted from electricity industry restructuring. The report is a case study of Southern California Edison's (SCE) load management programs. SCE was chosen because it operates one of the largest load management programs in the country and it operates them within a competitive wholesale electricity market. The report describes a wide range of existing and soon-to-be-available communication, control, and metering technologies that could be used to facilitate the evolution of SCE's load management programs and systems to provision of reliability services. The fundamental finding of this report is that, with modifications, SCE's load management infrastructure could be transitioned to provide critical ancillary services in competitive electricity markets, employing currently or soon-to-be available load control technologies.

  12. 76 FR 16277 - System Restoration Reliability Standards

    Science.gov (United States)

    2011-03-23

    ... electric system. Blackstart units are essential to restart generation and restore power to the grid in the... Standard EOP-007-0. \\2\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, 72 FR... = $5,894,624. Title: Mandatory Reliability Standards for the Bulk-Power System. Action: FERC 725A...

  13. Reliability and Cost Impacts for Attritable Systems

    Science.gov (United States)

    2017-03-23

    on reliability and cost: a probabilistic model. Electric Power Systems Research, 72(3), 213-224. Kalbfleisch, J.D. & Prentice, R.L. (1980). The...copyright protection in the United States. AFIT-ENV-MS-17-M-172 RELIABILITY AND COST IMPACTS FOR ATTRITABLE SYSTEMS THESIS Presented to... power of discrete time Markov chains, whether homogeneous or non-homogeneous, to model the reliability and dependability of repairable systems should

  14. System for the reliability analysis of the electric energy supply; Sistema para el analisis de confiabilidad del suministro de energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Perales, Favio; Martinez, Javier; Huesca, Francisco; Garcia, Norma; Nieva, Rolando [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    A computer tool, developed for the reliability evaluation of the electric energy supply, considering the faults in the generation and transmission systems, is presented. The application of the tool in planning the expansion and operation of the electric systems, the methodology of the solution employed and the various functions it accounts for, are described. At the end some illustrative examples of its applications by means of the studies with a model of representative characteristics of the interconnected national system. [Espanol] Se presenta una herramienta computacional desarrollada para evaluar la confiabilidad del suministro de energia electrica, considerando las fallas en los sistemas de generacion y transmision. Se describen las aplicaciones de la herramienta en la planeacion de la expansion y de la operacion de sistemas electricos, la metodologia de solucion empleada y las diversas funciones con que cuenta. Al final se presentan algunos ejemplos ilustrativos de sus aplicaciones mediante estudios con un modelo de caracteristicas representativas del sistema interconectado nacional.

  15. System for the reliability analysis of the electric energy supply; Sistema para el analisis de confiabilidad del suministro de energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Perales, Favio; Martinez, Javier; Huesca, Francisco; Garcia, Norma; Nieva, Rolando [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-12-31

    A computer tool, developed for the reliability evaluation of the electric energy supply, considering the faults in the generation and transmission systems, is presented. The application of the tool in planning the expansion and operation of the electric systems, the methodology of the solution employed and the various functions it accounts for, are described. At the end some illustrative examples of its applications by means of the studies with a model of representative characteristics of the interconnected national system. [Espanol] Se presenta una herramienta computacional desarrollada para evaluar la confiabilidad del suministro de energia electrica, considerando las fallas en los sistemas de generacion y transmision. Se describen las aplicaciones de la herramienta en la planeacion de la expansion y de la operacion de sistemas electricos, la metodologia de solucion empleada y las diversas funciones con que cuenta. Al final se presentan algunos ejemplos ilustrativos de sus aplicaciones mediante estudios con un modelo de caracteristicas representativas del sistema interconectado nacional.

  16. Novel approach for evaluation of service reliability for electricity customers

    Institute of Scientific and Technical Information of China (English)

    JIANG; John; N

    2009-01-01

    Understanding reliability value for electricity customer is important to market-based reliability management. This paper proposes a novel approach to evaluate the reliability for electricity customers by using indifference curve between economic compensation for power interruption and service reliability of electricity. Indifference curve is formed by calculating different planning schemes of network expansion for different reliability requirements of customers, which reveals the information about economic values for different reliability levels for electricity customers, so that the reliability based on market supply demand mechanism can be established and economic signals can be provided for reliability management and enhancement.

  17. Reliability analysis with the simulator S.ESCAF of a very complex sequential system: the electrical power supply system of a nuclear reactor

    International Nuclear Information System (INIS)

    Blot, M.

    1987-06-01

    The reliability analysis of complex sequential systems, in which the order of arrival of the events must be taken into account, can be very difficult, because the use of the classical modelling technique of Markov diagrams leads to an important limitation on the number of components which can be handled. The desk-top apparatus S.ESCAF, which electronically simulates very closely the behaviour of the system being studied, and is very easy to use, even by a non specialist in electronics, allows one to avoid these inconveniences and to enlarge considerably the analysis possibilities. This paper shows the application of the S.ESCAF method to the electrical power supply system of a nuclear reactor. This system requires the simulation of more than forty components with about sixty events such as failure, repair and refusal to start. A comparison of times necessary to perform the analysis by these means and by other methods is described, and the advantages of S.ESCAF are presented

  18. 10 CFR 500.3 - Electric regions-electric region groupings for reliability measurements under the Powerplant and...

    Science.gov (United States)

    2010-01-01

    ... System (APS)—7, except Duquesne Light Company. 2. American Electric Power System (AEP)—entire AEP System... 10 Energy 4 2010-01-01 2010-01-01 false Electric regions-electric region groupings for reliability... of electric regions for use with regard to the Act. The regions are identified by FERC Power Supply...

  19. Load Control System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, Daniel [Montana Tech of the Univ. of Montana, Butte, MT (United States)

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  20. Design for Reliability of Power Electronic Systems

    DEFF Research Database (Denmark)

    Wang, Huai; Ma, Ke; Blaabjerg, Frede

    2012-01-01

    Advances in power electronics enable efficient and flexible processing of electric power in the application of renewable energy sources, electric vehicles, adjustable-speed drives, etc. More and more efforts are devoted to better power electronic systems in terms of reliability to ensure high......). A collection of methodologies based on Physics-of-Failure (PoF) approach and mission profile analysis are presented in this paper to perform reliability-oriented design of power electronic systems. The corresponding design procedures and reliability prediction models are provided. Further on, a case study...... on a 2.3 MW wind power converter is discussed with emphasis on the reliability critical components IGBTs. Different aspects of improving the reliability of the power converter are mapped. Finally, the challenges and opportunities to achieve more reliable power electronic systems are addressed....

  1. Reliability of power system with open access

    International Nuclear Information System (INIS)

    Ehsani, A.; Ranjbar, A. M.; Fotuhi Firuzabad, M.; Ehsani, M.

    2003-01-01

    Recently, in many countries, electric utility industry is undergoing considerable changes in regard to its structure and regulation. It can be clearly seen that the thrust towards privatization and deregulation or re regulation of the electric utility industry will introduce numerous reliability problems that will require new criteria and analytical tools that recognize the residual uncertainties in the new environment. In this paper, different risks and uncertainties in competitive electricity markets are briefly introduced; the approach of customers, operators, planners, generation bodies and network providers to the reliability of deregulated system is studied; the impact of dispersed generation on system reliability is evaluated; and finally, the reliability cost/reliability worth issues in the new competitive environment are considered

  2. power system reliability in supplying nuclear reactors

    International Nuclear Information System (INIS)

    Gad, M.M.M.

    2007-01-01

    this thesis presents a simple technique for deducing minimal cut set (MCS) from the defined minimal path set (MPS) of generic distribution system and this technique have been used to evaluate the basic reliability indices of Egypt's second research reactor (ETRR-2) electrical distribution network. the alternative system configurations are then studied to evaluate their impact on service reliability. the proposed MCS approach considers both sustained and temporary outage. the temporary outage constitutes an important parameter in characterizing the system reliability indices for critical load point in distribution system. it is also consider the power quality impact on the reliability indices

  3. Load As A Reliability Resource in the Restructured Electricity Market

    Energy Technology Data Exchange (ETDEWEB)

    Kueck, J.D.

    2002-06-10

    Recent electricity price spikes are painful reminders of the value that meaningful demand-side responses could bring to the restructuring US electricity system. Review of the aggregate offers made by suppliers confirms that even a modest increase in demand elasticity could dramatically reduce these extremes in price volatility. There is a strong need for dramatically increased customer participation in these markets to enhance system reliability and reduce price volatility. Indeed, allowing customers to manage their loads in response to system conditions might be thought of as the ultimate reliability resource. Most would agree that meaningful demand-side responses to price are the hallmark of a well-functioning competitive market [1]. Yet, in today's markets for electricity, little or no such response is evident. The reason is simple: customers currently do not experience directly the time-varying costs of their consumption decisions. Consequently, they have no incentive to modify these decisions in ways that might enhance system reliability or improve the efficiency of the markets in which electricity is traded. Increased customer participation is a necessary step in the evolution toward more efficient markets for electricity and ancillary services. This scoping report provides a three-part assessment of the current status of efforts to enhance the ability of customer's load to participate in competitive markets with a specific focus on the role of customer loads in enhancing electricity system reliability. First, this report considers the definitions of electricity-reliability-enhancing ancillary services (Section 2) and a preliminary assessment of the ability of customer's loads to provide these services. Second, is a review a variety of programs in which load has been called on as a system reliability resource (Section 3). These experiences, drawn from both past and current utility and ISO programs, focus on programs triggered by system

  4. An artificial intelligence system for reliability studies

    International Nuclear Information System (INIS)

    Llory, M.; Ancelin, C.; Bannelier, M.; Bouhadana, H.; Bouissou, M.; Lucas, J.Y.; Magne, L.; Villate, N.

    1990-01-01

    The EDF (French Electricity Company) software developed for computer aided reliability studies is considered. Such software tools were applied in the study of the safety requirements of the Paluel nuclear power plant. The reliability models, based on IF-THEN type rules, and the generation of models by the expert system are described. The models are then processed applying algorithm structures [fr

  5. Power system reliability analysis using fault trees

    International Nuclear Information System (INIS)

    Volkanovski, A.; Cepin, M.; Mavko, B.

    2006-01-01

    The power system reliability analysis method is developed from the aspect of reliable delivery of electrical energy to customers. The method is developed based on the fault tree analysis, which is widely applied in the Probabilistic Safety Assessment (PSA). The method is adapted for the power system reliability analysis. The method is developed in a way that only the basic reliability parameters of the analysed power system are necessary as an input for the calculation of reliability indices of the system. The modeling and analysis was performed on an example power system consisting of eight substations. The results include the level of reliability of current power system configuration, the combinations of component failures resulting in a failed power delivery to loads, and the importance factors for components and subsystems. (author)

  6. Assessing reliability in energy supply systems

    International Nuclear Information System (INIS)

    McCarthy, Ryan W.; Ogden, Joan M.; Sperling, Daniel

    2007-01-01

    Reliability has always been a concern in the energy sector, but concerns are escalating as energy demand increases and the political stability of many energy supply regions becomes more questionable. But how does one define and measure reliability? We introduce a method to assess reliability in energy supply systems in terms of adequacy and security. It derives from reliability assessment frameworks developed for the electricity sector, which are extended to include qualitative considerations and to be applicable to new energy systems by incorporating decision-making processes based on expert opinion and multi-attribute utility theory. The method presented here is flexible and can be applied to any energy system. To illustrate its use, we apply the method to two hydrogen pathways: (1) centralized steam reforming of imported liquefied natural gas with pipeline distribution of hydrogen, and (2) on-site electrolysis of water using renewable electricity produced independently from the electricity grid

  7. RELIABILITY ANALYSIS OF POWER DISTRIBUTION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Popescu V.S.

    2012-04-01

    Full Text Available Power distribution systems are basic parts of power systems and reliability of these systems at present is a key issue for power engineering development and requires special attention. Operation of distribution systems is accompanied by a number of factors that produce random data a large number of unplanned interruptions. Research has shown that the predominant factors that have a significant influence on the reliability of distribution systems are: weather conditions (39.7%, defects in equipment(25% and unknown random factors (20.1%. In the article is studied the influence of random behavior and are presented estimations of reliability of predominantly rural electrical distribution systems.

  8. Evaluating North American Electric Grid Reliability Using the Barabasi-Albert Network Model

    OpenAIRE

    Chassin, David P.; Posse, Christian

    2004-01-01

    The reliability of electric transmission systems is examined using a scale-free model of network structure and failure propagation. The topologies of the North American eastern and western electric networks are analyzed to estimate their reliability based on the Barabasi-Albert network model. A commonly used power system reliability index is computed using a simple failure propagation model. The results are compared to the values of power system reliability indices previously obtained using s...

  9. Puget Sound area electric reliability plan

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    Various conservation, load management, and fuel switching programs were considered as ways to reduce or shift system peak load. These programs operate at the end-use level, such as residential water heat. Figure D-1a shows what electricity consumption for water heat looks like on normal and extreme peak days. Load management programs, such as water heat control, are designed to reduce electricity consumption at the time of system peak. On the coldest day in average winter, system load peaks near 8:00 a.m. In a winter with extremely cold weather, electricity consumption increases fr all hours, and the system peak shifts to later in the morning. System load shapes in the Puget Sound area are shown in Figure D-1b for a normal winter peak day (February 2, 1988) and extreme peak day (February 3, 1989). Peak savings from any program are calculated to be the reduction in loads on the entire system at the hour of system peak. Peak savings for all programs are measured at 8:00 a.m. on a normal peak day and 9:00 a.m. on an extreme peak day. On extremely cold day, some water heat load shifts to much later in the morning, with less load available for shedding at the time of system peak. Models of hourly end-use consumption were constructed to simulate the impact of conservation, land management, and fuel switching programs on electricity consumption. Javelin, a time-series simulating package for personal computers, was chosen for the hourly analysis. Both a base case and a program case were simulated. 15 figs., 7 tabs.

  10. Research on the Reliability Testing of Electrical Automation Control Equipment

    OpenAIRE

    Yongjie Luo

    2014-01-01

    According to the author’s many years’ work experience, this paper first discusses the concepts of electrical automation control equipment reliability testing, and then analyzes the test method of electrical automation control equipment reliability testing, finally, on this basis, this article discusses how to determine the reliability test method of electrical automation control equipment. Results of this study will provide a useful reference for electrical automation control equipment reliab...

  11. PV Systems Reliability Final Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Lavrova, Olga [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Flicker, Jack David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Armijo, Kenneth Miguel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gonzalez, Sigifredo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schindelholz, Eric John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorensen, Neil R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yang, Benjamin Bing-Yeh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    The continued exponential growth of photovoltaic technologies paves a path to a solar-powered world, but requires continued progress toward low-cost, high-reliability, high-performance photovoltaic (PV) systems. High reliability is an essential element in achieving low-cost solar electricity by reducing operation and maintenance (O&M) costs and extending system lifetime and availability, but these attributes are difficult to verify at the time of installation. Utilities, financiers, homeowners, and planners are demanding this information in order to evaluate their financial risk as a prerequisite to large investments. Reliability research and development (R&D) is needed to build market confidence by improving product reliability and by improving predictions of system availability, O&M cost, and lifetime. This project is focused on understanding, predicting, and improving the reliability of PV systems. The two areas being pursued include PV arc-fault and ground fault issues, and inverter reliability.

  12. Basic Principles of Electrical Network Reliability Optimization in Liberalised Electricity Market

    Science.gov (United States)

    Oleinikova, I.; Krishans, Z.; Mutule, A.

    2008-01-01

    The authors propose to select long-term solutions to the reliability problems of electrical networks in the stage of development planning. The guide lines or basic principles of such optimization are: 1) its dynamical nature; 2) development sustainability; 3) integrated solution of the problems of network development and electricity supply reliability; 4) consideration of information uncertainty; 5) concurrent consideration of the network and generation development problems; 6) application of specialized information technologies; 7) definition of requirements for independent electricity producers. In the article, the major aspects of liberalized electricity market, its functions and tasks are reviewed, with emphasis placed on the optimization of electrical network development as a significant component of sustainable management of power systems.

  13. The reliability assessment of the electromagnetic valve of high-speed electric multiple units braking system based on two-parameter exponential distribution

    Directory of Open Access Journals (Sweden)

    Jianwei Yang

    2016-06-01

    Full Text Available In order to solve the reliability assessment of braking system component of high-speed electric multiple units, this article, based on two-parameter exponential distribution, provides the maximum likelihood estimation and Bayes estimation under a type-I life test. First of all, we evaluate the failure probability value according to the classical estimation method and then obtain the maximum likelihood estimation of parameters of two-parameter exponential distribution by performing and using the modified likelihood function. On the other hand, based on Bayesian theory, this article also selects the beta and gamma distributions as the prior distribution, combines with the modified maximum likelihood function, and innovatively applies a Markov chain Monte Carlo algorithm to parameters assessment based on Bayes estimation method for two-parameter exponential distribution, so that two reliability mathematical models of the electromagnetic valve are obtained. Finally, through type-I life test, the failure rates according to maximum likelihood estimation and Bayes estimation method based on Markov chain Monte Carlo algorithm are, respectively, 2.650 × 10−5 and 3.037 × 10−5. Compared with the failure rate of a electromagnetic valve 3.005 × 10−5, it proves that the Bayes method can use a Markov chain Monte Carlo algorithm to estimate reliability for two-parameter exponential distribution and Bayes estimation is more closer to the value of electromagnetic valve. So, by fully integrating multi-source, Bayes estimation method can preferably modify and precisely estimate the parameters, which can provide a certain theoretical basis for the safety operation of high-speed electric multiple units.

  14. Managing relationships between electric power industry restructuring and grid reliability

    International Nuclear Information System (INIS)

    Thomas, R.J.

    2005-01-01

    The electricity system is a critical infrastructure, and its continued and reliable functioning is essential to the nation's economy and well-being. However, the inter-dependency of electricity networks is not completely understood. The economic impact of outages was discussed in this white paper. It was suggested that moving to a restructured environment has degraded the reliability of the bulk system. New institutional arrangements and approaches to information management are needed. It was suggested that reliability practices caused the 2003 blackout, and not technical failures. Uncertainties in the restructured market were discussed, as well as incentives to maintain system adequacy. Examples of deregulation in other countries were presented. Organizational complexities were reviewed, including the Federal Energy Regulatory Commission's (FERC) requirements and the new layers of complexity that have been added to the decision-making process in the light of restructuring. Planning and connectivity issues were reviewed. The need for design standards in power grid control centres was discussed. Difficulties in collecting data from different control centres were considered. Issues concerning the lack of investment in research and development were discussed, with particular reference to the urgent need for coordinated research programs. The looming manpower crisis in the electric power industry was also discussed. Recommendations included ensuring that the transmission system can support a market structure; building a national reliability centre; solving the manpower crisis; and testing market designs before deploying them. It was concluded that good engineering design principles, including experimental economic testing, should be required of any new electricity market design before authorizing its use. 31 refs., 1 tab., 6 figs

  15. Reliability payments to generation capacity in electricity markets

    International Nuclear Information System (INIS)

    Olsina, Fernando; Pringles, Rolando; Larisson, Carlos; Garcés, Francisco

    2014-01-01

    Electric power is a critical input to modern economies. Generation adequacy and security of supply in power systems running under competition are currently topics of high concern for consumers, regulators and governments. In a market setting, generation investments and adequacy can only be achieved by an appropriate regulatory framework that sets efficient remuneration to power capacity. Theoretically, energy-only electricity markets are efficient and no additional mechanism is needed. Nonetheless, the energy-only market design suffers from serious drawbacks. Therefore, jointly with the evolution of electricity markets, many remunerating mechanisms for generation capacity have been proposed. Explicit capacity payment was the first remunerating approach implemented and perhaps still the most applied. However, this price-based regulation has been applied no without severe difficulties and criticism. In this paper, a new reliability payment mechanism is envisioned. Capacity of each generating unit is paid according to its effective contribution to overall system reliability. The proposed scheme has many attractive features and preserves the theoretical efficiency properties of energy-only markets. Fairness, incentive compatibility, market power mitigation and settlement rules are investigated in this work. The article also examines the requirements for system data and models in order to implement the proposed capacity mechanism. A numerical example on a real hydrothermal system serves for illustrating the practicability of the proposed approach and the resulting reliability payments to the generation units. - Highlights: • A new approach for remunerating supply reliability provided by generation units is proposed. • The contribution of each generating unit to lessen power shortfalls is determined by simulations. • Efficiency, fairness and incentive compatibility of the proposed reliability payment are assessed

  16. Electric Power quality Analysis in research reactor: Impacts on nuclear safety assessment and electrical distribution reliability

    International Nuclear Information System (INIS)

    Touati, Said; Chennai, Salim; Souli, Aissa

    2015-01-01

    The increased requirements on supervision, control, and performance in modern power systems make power quality monitoring a common practise for utilities. Large databases are created and automatic processing of the data is required for fast and effective use of the available information. Aim of the work presented in this paper is the development of tools for analysis of monitoring power quality data and in particular measurements of voltage and currents in various level of electrical power distribution. The study is extended to evaluate the reliability of the electrical system in nuclear plant. Power Quality is a measure of how well a system supports reliable operation of its loads. A power disturbance or event can involve voltage, current, or frequency. Power disturbances can originate in consumer power systems, consumer loads, or the utility. The effect of power quality problems is the loss power supply leading to severe damage to equipments. So, we try to track and improve system reliability. The assessment can be focused on the study of impact of short circuits on the system, harmonics distortion, power factor improvement and effects of transient disturbances on the Electrical System during motor starting and power system fault conditions. We focus also on the review of the Electrical System design against the Nuclear Directorate Safety Assessment principles, including those extended during the last Fukushima nuclear accident. The simplified configuration of the required system can be extended from this simple scheme. To achieve these studies, we have used a demo ETAP power station software for several simulations. (authors)

  17. Electric Power quality Analysis in research reactor: Impacts on nuclear safety assessment and electrical distribution reliability

    Energy Technology Data Exchange (ETDEWEB)

    Touati, Said; Chennai, Salim; Souli, Aissa [Nuclear Research Centre of Birine, Ain Oussera, Djelfa Province (Algeria)

    2015-07-01

    The increased requirements on supervision, control, and performance in modern power systems make power quality monitoring a common practise for utilities. Large databases are created and automatic processing of the data is required for fast and effective use of the available information. Aim of the work presented in this paper is the development of tools for analysis of monitoring power quality data and in particular measurements of voltage and currents in various level of electrical power distribution. The study is extended to evaluate the reliability of the electrical system in nuclear plant. Power Quality is a measure of how well a system supports reliable operation of its loads. A power disturbance or event can involve voltage, current, or frequency. Power disturbances can originate in consumer power systems, consumer loads, or the utility. The effect of power quality problems is the loss power supply leading to severe damage to equipments. So, we try to track and improve system reliability. The assessment can be focused on the study of impact of short circuits on the system, harmonics distortion, power factor improvement and effects of transient disturbances on the Electrical System during motor starting and power system fault conditions. We focus also on the review of the Electrical System design against the Nuclear Directorate Safety Assessment principles, including those extended during the last Fukushima nuclear accident. The simplified configuration of the required system can be extended from this simple scheme. To achieve these studies, we have used a demo ETAP power station software for several simulations. (authors)

  18. Structural systems reliability analysis

    International Nuclear Information System (INIS)

    Frangopol, D.

    1975-01-01

    For an exact evaluation of the reliability of a structure it appears necessary to determine the distribution densities of the loads and resistances and to calculate the correlation coefficients between loads and between resistances. These statistical characteristics can be obtained only on the basis of a long activity period. In case that such studies are missing the statistical properties formulated here give upper and lower bounds of the reliability. (orig./HP) [de

  19. Multi-Disciplinary System Reliability Analysis

    Science.gov (United States)

    Mahadevan, Sankaran; Han, Song

    1997-01-01

    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code developed under the leadership of NASA Lewis Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multi-disciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  20. Small nuclear power reactor emergency electric power supply system reliability comparative analysis; Analise da confiabilidade do sistema de suprimento de energia eletrica de emergencia de um reator nuclear de pequeno porte

    Energy Technology Data Exchange (ETDEWEB)

    Bonfietti, Gerson

    2003-07-01

    This work presents an analysis of the reliability of the emergency power supply system, of a small size nuclear power reactor. Three different configurations are investigated and their reliability analyzed. The fault tree method is used as the main tool of analysis. The work includes a bibliographic review of emergency diesel generator reliability and a discussion of the design requirements applicable to emergency electrical systems. The influence of common cause failure influences is considered using the beta factor model. The operator action is considered using human failure probabilities. A parametric analysis shows the strong dependence between the reactor safety and the loss of offsite electric power supply. It is also shown that common cause failures can be a major contributor to the system reliability. (author)

  1. 75 FR 35689 - System Personnel Training Reliability Standards

    Science.gov (United States)

    2010-06-23

    ... planning staff at control areas and reliability coordinators concerning power system characteristics and... Coordination--Staffing). \\11\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, Federal... American bulk electric system are competent to perform those reliability-related tasks.\\22\\ The proposed...

  2. 75 FR 72664 - System Personnel Training Reliability Standards

    Science.gov (United States)

    2010-11-26

    ...--Staffing). \\2\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, 72 FR 16416 (Apr... on the North American bulk electric system are competent to perform those reliability-related tasks... PER-004-2 will achieve a significant improvement in the reliability of the Bulk- Power System and...

  3. Puget Sound area electric reliability plan. Draft environmental impact statement

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    The Puget Sound Area Electric Reliability Plan Draft Environmental Impact Statement (DEIS) identifies the alternatives for solving a power system problem in the Puget Sound area. This Plan is undertaken by Bonneville Power Administration (BPA), Puget Sound Power & Light, Seattle City Light, Snohomish Public Utility District No. 1 (PUD), and Tacoma Public Utilities. The Plan consists of potential actions in Puget Sound and other areas in the State of Washington. A specific need exists in the Puget Sound area for balance between east-west transmission capacity and the increasing demand to import power generated east of the Cascades. At certain times of the year, there is more demand for power than the electric system can supply in the Puget Sound area. This high demand, called peak demand, occurs during the winter months when unusually cold weather increases electricity use for heating. The existing power system can supply enough power if no emergencies occur. However, during emergencies, the system will not operate properly. As demand grows, the system becomes more strained. To meet demand, the rate of growth of demand must be reduced or the ability to serve the demand must be increased, or both. The plan to balance Puget Sound`s power demand and supply has these purposes: The plan should define a set of actions that would accommodate ten years of load growth (1994--2003). Federal and State environmental quality requirements should be met. The plan should be consistent with the plans of the Northwest Power Planning Council. The plan should serve as a consensus guideline for coordinated utility action. The plan should be flexible to accommodate uncertainties and differing utility needs. The plan should balance environmental impacts and economic costs. The plan should provide electric system reliability consistent with customer expectations. 29 figs., 24 tabs.

  4. Puget Sound Area Electric Reliability Plan : Draft Environmental Impact State.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1991-09-01

    The Puget Sound Area Electric Reliability Plan Draft Environmental Impact Statement (DEIS) identifies the alternatives for solving a power system problem in the Puget Sound area. This Plan is undertaken by Bonneville Power Administration (BPA), Puget Sound Power Light, Seattle City Light, Snohomish Public Utility District No. 1 (PUD), and Tacoma Public Utilities. The Plan consists of potential actions in Puget Sound and other areas in the State of Washington. A specific need exists in the Puget Sound area for balance between east-west transmission capacity and the increasing demand to import power generated east of the Cascades. At certain times of the year, there is more demand for power than the electric system can supply in the Puget Sound area. This high demand, called peak demand, occurs during the winter months when unusually cold weather increases electricity use for heating. The existing power system can supply enough power if no emergencies occur. However, during emergencies, the system will not operate properly. As demand grows, the system becomes more strained. To meet demand, the rate of growth of demand must be reduced or the ability to serve the demand must be increased, or both. The plan to balance Puget Sound's power demand and supply has these purposes: The plan should define a set of actions that would accommodate ten years of load growth (1994--2003). Federal and State environmental quality requirements should be met. The plan should be consistent with the plans of the Northwest Power Planning Council. The plan should serve as a consensus guideline for coordinated utility action. The plan should be flexible to accommodate uncertainties and differing utility needs. The plan should balance environmental impacts and economic costs. The plan should provide electric system reliability consistent with customer expectations. 29 figs., 24 tabs.

  5. The expansion of electric power systems considering the operation reliability; Expansion de sistemas electricos considerando la securidad de servicio

    Energy Technology Data Exchange (ETDEWEB)

    Cortes, Marcelo A. [Universidad de Antofagasta (Chile). Dept. de Ingenieria Electrica; Moya A, Oscar [Chile Univ., Santiago (Chile). Dept. de Ingenieria Civil

    1997-12-31

    This publication describes a procedure based in an linear programming for the planning of the expansion of mediating term in power systems. The implicit alternatives for network expansion, whether power plants or transmission lines, are classified according to indexes of reinforcement. The indexes are gotten resulting shadow pricing upon resolving a problem of minimum cost of operation and outage. The network is subjected to the most probable contingencies and from these outputs the expected reinforcement results are obtained. The problem of the reactive power accounts for restrictions in line capacity and prior evaluation of A C power flux. Results obtained are used for methodology validation. (author) 12 refs., 1 fig., 3 tabs.; e-mail: mcortes at apolo.cc.uantof.cl.; osmoya at tamarugo.cec.uchile.cl

  6. Distribution reliability in the reformed New Zealand electricity industry

    International Nuclear Information System (INIS)

    McGlinchy, B. J.

    1997-01-01

    The process of deregulating the electric power industry in New Zealand, which began in 1984, and is now a fully competitive system, was described. The industry is not only fully competitive, but enjoys the distinction of being subject only to very light-handed regulation. The regulation requires each company within the industry to publish an annual financial statement, the rate of profit and some performance indicators including reliability indices. Companies also report on faults in lines and cables, and on a voluntary basis they contribute to a 'by cause' survey, using indicators developed by the Canadian Electricity Association. It is expected that the indices that will be developed from this data will be used as benchmarks for performance. The data could also be used for probability analysis in system expansion programs. 6 refs., 7 figs

  7. Calculating system reliability with SRFYDO

    Energy Technology Data Exchange (ETDEWEB)

    Morzinski, Jerome [Los Alamos National Laboratory; Anderson - Cook, Christine M [Los Alamos National Laboratory; Klamann, Richard M [Los Alamos National Laboratory

    2010-01-01

    SRFYDO is a process for estimating reliability of complex systems. Using information from all applicable sources, including full-system (flight) data, component test data, and expert (engineering) judgment, SRFYDO produces reliability estimates and predictions. It is appropriate for series systems with possibly several versions of the system which share some common components. It models reliability as a function of age and up to 2 other lifecycle (usage) covariates. Initial output from its Exploratory Data Analysis mode consists of plots and numerical summaries so that the user can check data entry and model assumptions, and help determine a final form for the system model. The System Reliability mode runs a complete reliability calculation using Bayesian methodology. This mode produces results that estimate reliability at the component, sub-system, and system level. The results include estimates of uncertainty, and can predict reliability at some not-too-distant time in the future. This paper presents an overview of the underlying statistical model for the analysis, discusses model assumptions, and demonstrates usage of SRFYDO.

  8. TOPEX electrical power system

    Science.gov (United States)

    Chetty, P. R. K.; Roufberg, Lew; Costogue, Ernest

    1991-01-01

    The TOPEX mission requirements which impact the power requirements and analyses are presented. A description of the electrical power system (EPS), including energy management and battery charging methods that were conceived and developed to meet the identified satellite requirements, is included. Analysis of the TOPEX EPS confirms that all of its electrical performance and reliability requirements have been met. The TOPEX EPS employs the flight-proven modular power system (MPS) which is part of the Multimission Modular Spacecraft and provides high reliability, abbreviated development effort and schedule, and low cost. An energy balance equation, unique to TOPEX, has been derived to confirm that the batteries will be completely recharged following each eclipse, under worst-case conditions. TOPEX uses three NASA Standard 50AH Ni-Cd batteries, each with 22 cells in series. The MPS contains battery charge control and protection based on measurements of battery currents, voltages, temperatures, and computed depth-of-discharge. In case of impending battery depletion, the MPS automatically implements load shedding.

  9. Reliability Approach of a Compressor System using Reliability Block ...

    African Journals Online (AJOL)

    pc

    2018-03-05

    Mar 5, 2018 ... This paper presents a reliability analysis of such a system using reliability ... Keywords-compressor system, reliability, reliability block diagram, RBD .... the same structure has been kept with the three subsystems: air flow, oil flow and .... and Safety in Engineering Design", Springer, 2009. [3] P. O'Connor ...

  10. Field reliability of electronic systems

    International Nuclear Information System (INIS)

    Elm, T.

    1984-02-01

    This report investigates, through several examples from the field, the reliability of electronic units in a broader sense. That is, it treats not just random parts failure, but also inadequate reliability design and (externally and internally) induced failures. The report is not meant to be merely an indication of the state of the art for the reliability prediction methods we know, but also as a contribution to the investigation of man-machine interplay in the operation and repair of electronic equipment. The report firmly links electronics reliability to safety and risk analyses approaches with a broader, system oriented view of reliability prediction and with postfailure stress analysis. It is intended to reveal, in a qualitative manner, the existence of symptom and cause patterns. It provides a background for further investigations to identify the detailed mechanisms of the faults and the remedical actions and precautions for achieving cost effective reliability. (author)

  11. Reliability evaluation of power systems

    CERN Document Server

    Billinton, Roy

    1996-01-01

    The Second Edition of this well-received textbook presents over a decade of new research in power system reliability-while maintaining the general concept, structure, and style of the original volume. This edition features new chapters on the growing areas of Monte Carlo simulation and reliability economics. In addition, chapters cover the latest developments in techniques and their application to real problems. The text also explores the progress occurring in the structure, planning, and operation of real power systems due to changing ownership, regulation, and access. This work serves as a companion volume to Reliability Evaluation of Engineering Systems: Second Edition (1992).

  12. 77 FR 7526 - Interpretation of Protection System Reliability Standard

    Science.gov (United States)

    2012-02-13

    ... Federal Power Act (FPA) requires a Commission-certified Electric Reliability Organization (ERO) to develop.... Cir. 2009). \\8\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats... a person that is ``directly and materially affected'' by Bulk-Power System reliability may request...

  13. Reliability optimization in compound electric power systems with the aid of evolutionary algorithms; Optimizacion de la confiabilidad en sistemas electricos de potencia compuestos utilizando algoritmos evolucionarios

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Hernandez, Jose Alberto

    2001-11-15

    The purpose of evaluating the reliability of Electric Power Systems is to estimate the ability of the system to carry out their function of taking the energy from the generating stations to the load points. This involves the reliability of generation sources and transmission that affect in the transfer of power through the transmission system that bears load loss and voltage sags between the generation and the consumption centers. In this thesis a hybrid methodology that optimize the reliability in systems generation -transmission using evolutionary algorithms is developed. This technique of optimization determines the optimum number of components (parallel redundancy in lines) and shunt compensation in load nodes necessary to maximize reliability, subject to cost restrictions, and considering security conditions in steady state, using the smallest singular value technique. The objective function will be defined as stochastic function, where the measure of interests is the smallest singular value of the Jacobian matrix of power flows solution of the most severe event according to the evaluation of reliability of the generation transmission system, this formulation is a combination of integer and continuous non linear programming, where the conventional mathematical programming algorithms present difficulties in robustness and global optimal search. The fault in generation units is determined by using the state sampling together with the transmission system by Monte Carlo simulation for a desired load level. For events where violations in security exist (lines loading, violation in voltage in load nodes and violation in reactive power of generation nodes) a model of active and reactive power dispatch is used in order to correct these violations by means of the exact penalty function linear programming technique to proceeded to determine the stability of voltage in steady state by means of the smallest singular value technique and the participation factors of nodes

  14. Reliable inverter systems

    Science.gov (United States)

    Nagano, S.

    1979-01-01

    Base driver with common-load-current feedback protects paralleled inverter systems from open or short circuits. Circuit eliminates total system oscillation that can occur in conventional inverters because of open circuit in primary transformer winding. Common feedback signal produced by functioning modules forces operating frequency of failed module to coincide with clock drive so module resumes normal operating frequency in spite of open circuit.

  15. Nuclear electric propulsion operational reliability and crew safety study

    International Nuclear Information System (INIS)

    Karns, J.J.; Fragola, J.R.; Kahan, L.; Pelaccio, D.

    1993-01-01

    The central purpose of this analysis is to assess the ''achievability'' of a nuclear electric propulsion (NEP) system in a given mission. ''Achievability'' is a concept introduced to indicate the extent to which a system that meets or achieves its design goals might be implemented using the existing technology base. In the context of this analysis, the objective is to assess the achievability of an NEP system for a manned Mars mission as it pertains to operational reliability and crew safety goals. By varying design parameters, then examining the resulting system achievability, the design and mission risk drivers can be identified. Additionally, conceptual changes in design approach or mission strategy which are likely to improve overall achievability of the NEP system can be examined

  16. Reliability Evaluation for Optimizing Electricity Supply in a Developing Country

    OpenAIRE

    Mark Ndubuka NWOHU

    2007-01-01

    The reliability standards for electricity supply in a developing country, like Nigeria, have to be determined on past engineering principles and practice. Because of the high demand of electrical power due to rapid development, industrialization and rural electrification; the economic, social and political climate in which the electric power supply industry now operates should be critically viewed to ensure that the production of electrical power should be augmented and remain uninterrupted. ...

  17. Assessment and Improving Methods of Reliability Indices in Bakhtar Regional Electricity Company

    Directory of Open Access Journals (Sweden)

    Saeed Shahrezaei

    2013-04-01

    Full Text Available Reliability of a system is the ability of a system to do prospected duties in future and the probability of desirable operation for doing predetermined duties. Power system elements failures data are the main data of reliability assessment in the network. Determining antiseptic parameters is the goal of reliability assessment by using system history data. These parameters help to recognize week points of the system. In other words, the goal of reliability assessment is operation improving and decreasing of the failures and power outages. This paper is developed to assess reliability indices of Bakhtar Regional Electricity Company up to 1393 and the improving methods and their effects on the reliability indices in this network. DIgSILENT Power Factory software is employed for simulation. Simulation results show the positive effect of improving methods in reliability indices of Bakhtar Regional Electricity Company.

  18. 76 FR 23801 - North American Electric Reliability Corporation; Order Approving Reliability Standard

    Science.gov (United States)

    2011-04-28

    ... have an operating plan and facilities for backup functionality to ensure Bulk-Power System reliability... entity's primary control center on the reliability of the Bulk-Power System. \\1\\ Mandatory Reliability... potential impact of a violation of the Requirement on the reliability of the Bulk-Power System. The...

  19. Potential for deserts to supply reliable renewable electric power

    Science.gov (United States)

    Labordena, Mercè; Lilliestam, Johan

    2015-04-01

    To avoid dangerous climate change, the electricity systems must be decarbonized by mid-century. The world has sufficient renewable electricity resources for complete power sector decarbonization, but an expansion of renewables poses several challenges for the electricity systems. First, wind and solar PV power are intermittent and supply-controlled, making it difficult to securely integrate this fluctuating generation into the power systems. Consequently, power sources that are both renewable and dispatchable, such as biomass, hydro and concentrating solar power (CSP), are particularly important. Second, renewable power has a low power density and needs vast areas of land, which is problematic both due to cost reasons and due to land-use conflicts, in particular with agriculture. Renewable and dispatchable technologies that can be built in sparsely inhabited regions or on land with low competition with agriculture would therefore be especially valuable; this land-use competition greatly limits the potential for hydro and biomass electricity. Deserts, however, are precisely such low-competition land, and are at the same time the most suited places for CSP generation, but this option would necessitate long transmission lines from remote places in the deserts to the demand centers such as big cities. We therefore study the potential for fleets of CSP plants in the large deserts of the world to produce reliable and reasonable-cost renewable electricity for regions with high and/or rapidly increasing electricity demand and with a desert within or close to its borders. The regions in focus here are the European Union, North Africa and the Middle East, China and Australia. We conduct the analysis in three steps. First, we identify the best solar generation areas in the selected deserts using geographic information systems (GIS), and applying restrictions to minimize impact on biodiversity, soils, human heath, and land-use and land-cover change. Second, we identify

  20. Puget Sound Area Electric Reliability Plan : Final Environmental Impact Statement.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1992-04-01

    A specific need exists in the Puget Sound area for balance between east-west transmission capacity and the increasing demand to import power generated east of the Cascades. At certain times of the year, and during certain conditions, there is more demand for power in the Puget Sound area than the transmission system and existing generation can reliably supply. This high demand, called peak demand occurs during the winter months when unusually cold weather increases electricity use for heating. The existing power system can supply enough power if no emergencies occur. However, during emergencies the system will not operate properly. As demand grows, the system becomes more strained. To meet demand, the rate of growth of demand must be reduced or the ability to serve the demand must be increased, or both.

  1. On Bayesian System Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen Ringi, M

    1995-05-01

    The view taken in this thesis is that reliability, the probability that a system will perform a required function for a stated period of time, depends on a person`s state of knowledge. Reliability changes as this state of knowledge changes, i.e. when new relevant information becomes available. Most existing models for system reliability prediction are developed in a classical framework of probability theory and they overlook some information that is always present. Probability is just an analytical tool to handle uncertainty, based on judgement and subjective opinions. It is argued that the Bayesian approach gives a much more comprehensive understanding of the foundations of probability than the so called frequentistic school. A new model for system reliability prediction is given in two papers. The model encloses the fact that component failures are dependent because of a shared operational environment. The suggested model also naturally permits learning from failure data of similar components in non identical environments. 85 refs.

  2. On Bayesian System Reliability Analysis

    International Nuclear Information System (INIS)

    Soerensen Ringi, M.

    1995-01-01

    The view taken in this thesis is that reliability, the probability that a system will perform a required function for a stated period of time, depends on a person's state of knowledge. Reliability changes as this state of knowledge changes, i.e. when new relevant information becomes available. Most existing models for system reliability prediction are developed in a classical framework of probability theory and they overlook some information that is always present. Probability is just an analytical tool to handle uncertainty, based on judgement and subjective opinions. It is argued that the Bayesian approach gives a much more comprehensive understanding of the foundations of probability than the so called frequentistic school. A new model for system reliability prediction is given in two papers. The model encloses the fact that component failures are dependent because of a shared operational environment. The suggested model also naturally permits learning from failure data of similar components in non identical environments. 85 refs

  3. Reliability analysis of shutdown system

    International Nuclear Information System (INIS)

    Kumar, C. Senthil; John Arul, A.; Pal Singh, Om; Suryaprakasa Rao, K.

    2005-01-01

    This paper presents the results of reliability analysis of Shutdown System (SDS) of Indian Prototype Fast Breeder Reactor. Reliability analysis carried out using Fault Tree Analysis predicts a value of 3.5 x 10 -8 /de for failure of shutdown function in case of global faults and 4.4 x 10 -8 /de for local faults. Based on 20 de/y, the frequency of shutdown function failure is 0.7 x 10 -6 /ry, which meets the reliability target, set by the Indian Atomic Energy Regulatory Board. The reliability is limited by Common Cause Failure (CCF) of actuation part of SDS and to a lesser extent CCF of electronic components. The failure frequency of individual systems is -3 /ry, which also meets the safety criteria. Uncertainty analysis indicates a maximum error factor of 5 for the top event unavailability

  4. Engineering and Design: Reliability Analysis of Navigation Lock and Dam Mechanical and Electrical Equipment

    National Research Council Canada - National Science Library

    Beranek, Dwight

    2001-01-01

    This engineer technical letter (ETL) provides guidance for assessing the reliability of mechanical and electrical systems of navigation locks and dams and for establishing an engineering basis for major rehabilitation investment decisions...

  5. Component reliability for electronic systems

    CERN Document Server

    Bajenescu, Titu-Marius I

    2010-01-01

    The main reason for the premature breakdown of today's electronic products (computers, cars, tools, appliances, etc.) is the failure of the components used to build these products. Today professionals are looking for effective ways to minimize the degradation of electronic components to help ensure longer-lasting, more technically sound products and systems. This practical book offers engineers specific guidance on how to design more reliable components and build more reliable electronic systems. Professionals learn how to optimize a virtual component prototype, accurately monitor product reliability during the entire production process, and add the burn-in and selection procedures that are the most appropriate for the intended applications. Moreover, the book helps system designers ensure that all components are correctly applied, margins are adequate, wear-out failure modes are prevented during the expected duration of life, and system interfaces cannot lead to failure.

  6. Photovoltaic power system reliability considerations

    Science.gov (United States)

    Lalli, V. R.

    1980-01-01

    This paper describes an example of how modern engineering and safety techniques can be used to assure the reliable and safe operation of photovoltaic power systems. This particular application was for a solar cell power system demonstration project in Tangaye, Upper Volta, Africa. The techniques involve a definition of the power system natural and operating environment, use of design criteria and analysis techniques, an awareness of potential problems via the inherent reliability and FMEA methods, and use of a fail-safe and planned spare parts engineering philosophy.

  7. Reliability analysis of wind embedded power generation system for ...

    African Journals Online (AJOL)

    This paper presents a method for Reliability Analysis of wind energy embedded in power generation system for Indian scenario. This is done by evaluating the reliability index, loss of load expectation, for the power generation system with and without integration of wind energy sources in the overall electric power system.

  8. 78 FR 38851 - Electric Reliability Organization Proposal To Retire Requirements in Reliability Standards

    Science.gov (United States)

    2013-06-28

    ... either: Provide little protection for Bulk-Power System reliability or are redundant with other aspects... for retirement either: (1) Provide little protection for Bulk-Power System reliability or (2) are... to assure reliability of the Bulk-Power System and should be withdrawn. We have identified 41...

  9. System reliability of corroding pipelines

    International Nuclear Information System (INIS)

    Zhou Wenxing

    2010-01-01

    A methodology is presented in this paper to evaluate the time-dependent system reliability of a pipeline segment that contains multiple active corrosion defects and is subjected to stochastic internal pressure loading. The pipeline segment is modeled as a series system with three distinctive failure modes due to corrosion, namely small leak, large leak and rupture. The internal pressure is characterized as a simple discrete stochastic process that consists of a sequence of independent and identically distributed random variables each acting over a period of one year. The magnitude of a given sequence follows the annual maximum pressure distribution. The methodology is illustrated through a hypothetical example. Furthermore, the impact of the spatial variability of the pressure loading and pipe resistances associated with different defects on the system reliability is investigated. The analysis results suggest that the spatial variability of pipe properties has a negligible impact on the system reliability. On the other hand, the spatial variability of the internal pressure, initial defect sizes and defect growth rates can have a significant impact on the system reliability.

  10. Pervasive Electricity Distribution System

    Directory of Open Access Journals (Sweden)

    Muhammad Usman Tahir

    2017-06-01

    Full Text Available Now a days a country cannot become economically strong until and unless it has enough electrical power to fulfil industrial and domestic needs. Electrical power being the pillar of any country’s economy, needs to be used in an efficient way. The same step is taken here by proposing a new system for energy distribution from substation to consumer houses, also it monitors the consumer consumption and record data. Unlike traditional manual Electrical systems, pervasive electricity distribution system (PEDS introduces a fresh perspective to monitor the feeder line status at distribution and consumer level. In this system an effort is taken to address the issues of electricity theft, manual billing, online monitoring of electrical distribution system and automatic control of electrical distribution points. The project is designed using microcontroller and different sensors, its GUI is designed in Labview software.

  11. Factors influencing the reliability of non-electric detonating circuit in underground uranium mines and preventive measures of misfiring

    International Nuclear Information System (INIS)

    Li Qin

    2010-01-01

    Characteristics of non-electric detonating circuit are introduced. The main factors influencing the reliability of non-electric detonating circuit are described. Taking an underground blasting of a uranium mine for example, the reliability of various kinds of detonating network system is calculated using the reliability theory and numerical analysis method. The reasons that cause the misfiring in non-electric detonating circuit system are analyzed, and preventive measures are put forward.(authors)

  12. Autonomously managed electrical power systems

    Science.gov (United States)

    Callis, Charles P.

    1986-01-01

    The electric power systems for future spacecraft such as the Space Station will necessarily be more sophisticated and will exhibit more nearly autonomous operation than earlier spacecraft. These new power systems will be more reliable and flexible than their predecessors offering greater utility to the users. Automation approaches implemented on various power system breadboards are investigated. These breadboards include the Hubble Space Telescope power system test bed, the Common Module Power Management and Distribution system breadboard, the Autonomusly Managed Power System (AMPS) breadboard, and the 20 kilohertz power system breadboard. Particular attention is given to the AMPS breadboard. Future plans for these breadboards including the employment of artificial intelligence techniques are addressed.

  13. Dependent systems reliability estimation by structural reliability approach

    DEFF Research Database (Denmark)

    Kostandyan, Erik; Sørensen, John Dalsgaard

    2014-01-01

    Estimation of system reliability by classical system reliability methods generally assumes that the components are statistically independent, thus limiting its applicability in many practical situations. A method is proposed for estimation of the system reliability with dependent components, where...... the leading failure mechanism(s) is described by physics of failure model(s). The proposed method is based on structural reliability techniques and accounts for both statistical and failure effect correlations. It is assumed that failure of any component is due to increasing damage (fatigue phenomena...... identification. Application of the proposed method can be found in many real world systems....

  14. A COMPUTERIZED DIAGNOSTIC COMPLEX FOR RELIABILITY TESTING OF ELECTRIC MACHINES

    Directory of Open Access Journals (Sweden)

    O.О. Somka

    2015-06-01

    Full Text Available Purpose. To develop a diagnostic complex meeting the criteria and requirements for carrying out accelerated reliability test and realizing the basic modes of electric machines operation and performance of the posed problems necessary in the process of such test. Methodology. To determine and forecast the indices of electric machines reliability in accordance with the statistic data of repair plants we have conditionally divided them into structural parts that are most likely to fail. We have preliminarily assessed the state of each of these parts, which includes revelation of faults and deviations of technical and geometric parameters. We have determined the analyzed electric machine controlled parameters used for assessment of quantitative characteristics of reliability of these parts and electric machines on the whole. Results. As a result of the research, we have substantiated the structure of a computerized complex for electric machines reliability test. It allows us to change thermal and vibration actions without violation of the physics of the processes of aging and wearing of the basic structural parts and elements material. The above mentioned makes it possible to considerably reduce time spent on carrying out electric machines reliability tests and improve trustworthiness of the data obtained as a result of their performance. Originality. A special feature of determination of the controlled parameters consists in removal of vibration components in the idle mode and after disconnection of the analyzed electric machine from the power supply with the aim of singling out the vibration electromagnetic component, fixing the degree of sparking and bend of the shaft by means of phototechnique and local determination of structural parts temperature provided by corresponding location of thermal sensors. Practical value. We have offered a scheme of location of thermal and vibration sensors, which allows improvement of parameters measuring accuracy

  15. Puget Sound area electric reliability plan: Draft Environmental Impact Statement

    International Nuclear Information System (INIS)

    1992-04-01

    The purpose of this appendix to the draft environmental impact statement (EIS) report is to provide an update of the latest study work done on transmission system options for the Puget Sound Area Electric Reliability Plan. Also included in the attachments to the EIS are 2 reports analyzing the voltage stability of the Puget Sound transmission system and a review by Power Technologies, Inc. of the BPA voltage stability analysis and reactive options. Five transmission line options and several reactive options are presently being considered as possible solutions to the PSAFRP by the Transmission Team. The first two line options would be built on new rights-of way adjacent (as much as possible) to existing corridors. The reactive options would optimize the existing transmission system capability by adding new stations for series capacitors and/or switchgear. The other three line options are rebuilds or upgrades of existing cross mountain transmission lines. These options are listed below and include a preliminary assessment of the additional transmission system reinforcement required to integrate the new facilities into the existing transmission system. Plans were designed to provide at least 500 MVAR reactive margin

  16. PWR system reliability improvement activities

    International Nuclear Information System (INIS)

    Yoshikawa, Yuichiro

    1985-01-01

    In Japan lacking in energy resources, it is our basic energy policy to accelerate the development program of nuclear power, thereby reducing our dependence. As referred to in the foregoing, every effort has been exerted on our part to improve the PWR system reliability by dint of the so-called 'HOMEMADE' TQC activities, which is our brain-child as a result of applying to the energy industry the quality control philosophy developed in the field of manufacturing industry

  17. Reliability Issues in Stirling Radioisotope Power Systems

    Science.gov (United States)

    Schreiber, Jeffrey; Shah, Ashwin

    2005-01-01

    Stirling power conversion is a potential candidate for use in a Radioisotope Power System (RPS) for space science missions because it offers a multifold increase in the conversion efficiency of heat to electric power and reduced requirement of radioactive material. Reliability of an RPS that utilizes Stirling power conversion technology is important in order to ascertain long term successful performance. Owing to long life time requirement (14 years), it is difficult to perform long-term tests that encompass all the uncertainties involved in the design variables of components and subsystems comprising the RPS. The requirement for uninterrupted performance reliability and related issues are discussed, and some of the critical areas of concern are identified. An overview of the current on-going efforts to understand component life, design variables at the component and system levels, and related sources and nature of uncertainties are also discussed. Current status of the 110 watt Stirling Radioisotope Generator (SRG110) reliability efforts is described. Additionally, an approach showing the use of past experience on other successfully used power systems to develop a reliability plan for the SRG110 design is outlined.

  18. Reliability & availability of wind turbine electrical & electronic components

    NARCIS (Netherlands)

    Tavner, P.; Faulstich, S.; Hahn, B.; Bussel, van G.J.W.

    2010-01-01

    Recent analysis of European onshore wind turbine reliability data has shown that whilst wind turbine mechanical subassemblies tend to have relatively low failure rates but long downtimes, electrical and electronic subassemblies have relatively high failure rates and short downtimes. For onshore wind

  19. Operator reliability assessment system (OPERAS)

    International Nuclear Information System (INIS)

    Singh, A.; Spurgin, A.J.; Martin, T.; Welsch, J.; Hallam, J.W.

    1991-01-01

    OPERAS is a personal-computer (PC) based software to collect and process simulator data on control-room operators responses during requalification training scenarios. The data collection scheme is based upon approach developed earlier during the EPRI Operator Reliability Experiments project. The software allows automated data collection from simulator, thus minimizing simulator staff time and resources to collect, maintain and process data which can be useful in monitoring, assessing and enhancing the progress of crew reliability and effectiveness. The system is designed to provide the data and output information in the form of user-friendly charts, tables and figures for use by plant staff. OPERAS prototype software has been implemented at the Diablo Canyon (PWR) and Millstone (BWR) plants and is currently being used to collect operator response data. Data collected from similator include plant-state variables such as reactor pressure and temperature, malfunction, times at which annunciators are activated, operator actions and observations of crew behavior by training staff. The data and systematic analytical results provided by the OPERAS system can contribute to increase objectivity by the utility probabilistic risk analysis (PRA) and training staff in monitoring and assessing reliability of their crews

  20. Electrical system architecture

    Science.gov (United States)

    Algrain, Marcelo C [Peoria, IL; Johnson, Kris W [Washington, IL; Akasam, Sivaprasad [Peoria, IL; Hoff, Brian D [East Peoria, IL

    2008-07-15

    An electrical system for a vehicle includes a first power source generating a first voltage level, the first power source being in electrical communication with a first bus. A second power source generates a second voltage level greater than the first voltage level, the second power source being in electrical communication with a second bus. A starter generator may be configured to provide power to at least one of the first bus and the second bus, and at least one additional power source may be configured to provide power to at least one of the first bus and the second bus. The electrical system also includes at least one power consumer in electrical communication with the first bus and at least one power consumer in electrical communication with the second bus.

  1. The integrated North American electricity market : a bi-national model for securing a reliable supply of electricity

    International Nuclear Information System (INIS)

    Egan, T.

    2004-03-01

    The 50 million people who experienced the power blackout on August 14, 2003 in southern Ontario and the U.S. Midwest and Northeast understood how vital electricity is in our day-to-day lives, but they also saw the resiliency of the North American electricity system. More than 65 per cent of the power generation was restored to service within 12 hours and no damage was caused to the generation or transmission facilities. Although the interconnected North American electricity system is among the most reliable in the world, it is threatened by an aging infrastructure, lack of new generation and transmission to meet demand, and growing regulatory pressures. This report suggests that any measures that respond to the threat of ongoing reliability should be bi-national in scope due to the interconnected nature of the system. Currently, the market, regulatory and administrative systems are different in each country. The full engagement and cooperation of both Canada and the United States is important to ensure future cross-border trade and power reliability. The Canadian Electricity Association proposes the following 7 measures: (1) support an open debate on all the supply options available to meet growing power demands, (2) promote bi-national cooperation in the construction of new transmission capacity to ensure a reliable continental electricity system, (3) examine opportunities for bi-national cooperation for investment in advanced transmission technologies and transmission research and development, (4) promote new generation technology and demand-side measures to relieve existing transmission constraints and reduce the need for new transmission facilities, (5) endorse a self-governing international organization for developing and enforcing mandatory reliability standards for the electricity industry, (6) coordinate measures to promote critical infrastructure protection, and (7) harmonize U.S. and Canadian efforts to streamline or clarify regulation of electricity

  2. Predictive analysis on the electric energy distribution systems reliability: applying the synerGEE system; Analisis predictivo de la confiabilidad en los sistemas de distribucion de energia electrica: aplicando el sistema synerGEE

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Andrade, Carlos

    2008-12-15

    Electrical distribution systems ought to deliver electric power as economical as possible with an acceptable degree of service quality and continuity. Nevertheless, their faults represent one of the main causes of customer's unavailability. At the moment, a wide range of determinist criteria in the improvement of systems reliability based on past behavior are used, but they do not respond to the stochastic nature of system behavior, and are applied without an adequate balance between reliability and economy. In order to obtain this balance a minimum cost planning methodology that considers the predictive analysis of different investment alternatives in addition to the past behavior of the system is required, which guarantees that the economic resource available and limited will be used to gather the greater possible reliability degree. In this work this problem is approached with the fundamentals and methodologies needed to assess the design effects and operative criteria over the main reliability indexes used by the main utilities around the world, with emphasis on the need to optimize economical resources. The use of the system SynerGEETM, is investigated, probing it as a useful tool for the predictive reliability analysis. Due to the lack of experience that exists in Mexico with this type of analysis, distribution engineers has to become familiar with the concepts of the reliability engineering, their application to establish distribution systems models, and acquiring the ability to use the modern simulation tools, allowing them to evaluate the behavior of these systems with enough analytical rigor. In this sense a serial of well known study cases are presented to help them in this labor. [Spanish] Los sistemas de distribucion de energia electrica deben satisfacer la demanda de energia electrica de la forma mas economica posible, con un grado de calidad y continuidad aceptable. Sin embargo, sus fallas son una de las principales causas de indisponibilidad en

  3. ANALYSIS OF POWER SYSTEM RELIABILITY IMPROVEMENT FOR 74-BUS RADIAL DISTRIBUTION SYSTEM

    OpenAIRE

    Su Mon Myint*

    2018-01-01

    In Myanmar, electric power system planning is widely constructed because of more and more load growth and facing with failure of electricity, outage problems and system shut-down. Thus, not only making new power system network but also improving reliability of the existing system using suitable methods is very important to provide an adequate supply of electrical energy to its customers as economically and reliably as possible with an acceptable degree of continuity and quality that is design...

  4. 75 FR 80391 - Electric Reliability Organization Interpretations of Interconnection Reliability Operations and...

    Science.gov (United States)

    2010-12-22

    ... transmission (G&T) cooperative or similar organization to accept compliance responsibility on behalf of its... be found on the Commission's Web site; see, e.g., the ``Quick Reference Guide for Paper Submissions... Electric Reliability Standards, Order No. 672, FERC Stats. & Regs. ] 31,204, order on reh'g, Order No. 672...

  5. Electric distribution systems

    CERN Document Server

    Sallam, A A

    2010-01-01

    "Electricity distribution is the penultimate stage in the delivery of electricity to end users. The only book that deals with the key topics of interest to distribution system engineers, Electric Distribution Systems presents a comprehensive treatment of the subject with an emphasis on both the practical and academic points of view. Reviewing traditional and cutting-edge topics, the text is useful to practicing engineers working with utility companies and industry, undergraduate graduate and students, and faculty members who wish to increase their skills in distribution system automation and monitoring."--

  6. Shipboard electrical power systems

    CERN Document Server

    Patel, Mukund R

    2011-01-01

    Shipboard Electrical Power Systems addresses new developments in this growing field. Focused on the trend toward electrification to power commercial shipping, naval, and passenger vessels, this book helps new or experienced engineers master cutting-edge methods for power system design, control, protection, and economic use of power. Provides Basic Transferable Skills for Managing Electrical Power on Ships or on LandThis groundbreaking book is the first volume of its kind to illustrate optimization of all aspects of shipboard electrical power systems. Applying author Mukund Patel's rare combina

  7. Operator reliability assessment system (OPERAS)

    International Nuclear Information System (INIS)

    Spurgin, A.J.; Hallam, J.W.; Spurgin, J.P.; Singh, A.

    1991-01-01

    The paper gives an overview of the OPERAS project. It discusses the background which led to the design of the PC-based data collection and analysis system connected to plant training simulators including those used for nuclear power plants. The usefulness of a system like OPERAS was perceived during an earlier EPRI project, the Operator Reliability Experiments project, by EPRI and PG and E. The data collection and analysis approaches used in OPERAS were developed during the ORE project. The paper not only discusses the design of OPERAS but discusses the functions performed and the current experiences with the two prototype systems. Also listed are potential uses of OPERAS by utility personnel in Operations, Training and PRA groups

  8. Diakoptical reliability analysis of transistorized systems

    International Nuclear Information System (INIS)

    Kontoleon, J.M.; Lynn, J.W.; Green, A.E.

    1975-01-01

    Limitations both on high-speed core availability and computation time required for assessing the reliability of large-sized and complex electronic systems, such as used for the protection of nuclear reactors, are very serious restrictions which continuously confront the reliability analyst. Diakoptic methods simplify the solution of the electrical-network problem by subdividing a given network into a number of independent subnetworks and then interconnecting the solutions of these smaller parts by a systematic process involving transformations based on connection-matrix elements associated with the interconnecting links. However, the interconnection process is very complicated and it may be used only if the original system has been cut in such a manner that a relation can be established between the constraints appearing at both sides of the cut. Also, in dealing with transistorized systems, one of the difficulties encountered is that of modelling adequately their performance under various operating conditions, since their parameters are strongly affected by the imposed voltage and current levels. In this paper a new interconnection approach is presented which may be of use in the reliability analysis of large-sized transistorized systems. This is based on the partial optimization of the subdivisions of the torn network as well as on the optimization of the torn paths. The solution of the subdivisions is based on the principles of algebraic topology, with an algebraic structure relating the physical variables in a topological structure which defines the interconnection of the discrete elements. Transistors, and other nonlinear devices, are modelled using their actual characteristics, under normal and abnormal operating conditions. Use of so-called k factors is made to facilitate accounting for use of electrical stresses. The approach is demonstrated by way of an example. (author)

  9. Staff Report to the Secretary on Electricity Markets and Reliability

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-08-01

    Energy Secretary Rick Perry issued a memo in April of 2017 requesting a study and directing his staff to develop a report to include an assessment of the reliability and resilience of the electric grid and an overview of the evolution of electricity markets. Various factors have emerged over the past 15 years which have impacted power supply and demand in different ways. This study, prepared by experts throughout the Department, contains a comprehensive analysis of these factors and the corresponding data, and presents a series of recommendations meant to inform and guide policy makers, regulators, and the general public. Potential areas for further research are also presented.

  10. System Reliability of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    2010-01-01

    elements, alternate load path(s) etc. in the structural design. In general these characteristics can have a positive influence on system reliability of a structure however, in Eurocodes ductility is only awarded for concrete and steel structures but not for timber structures. It is well......-know that structural systems can redistribute internal forces due to ductility of a connection, i.e. some additional loads can be carried by the structure. The same effect is also possible for reinforced concrete structures and structures of steel. However, for timber structures codes do not award that ductility......For reduction of the risk of collapse in the event of loss of structural element(s), a structural engineer may take necessary steps to design a collapse-resistant structure that is insensitive to accidental circumstances e.g. by incorporating characteristics like redundancy, ties, ductility, key...

  11. 18 CFR 39.4 - Funding of the Electric Reliability Organization.

    Science.gov (United States)

    2010-04-01

    ... CERTIFICATION OF THE ELECTRIC RELIABILITY ORGANIZATION; AND PROCEDURES FOR THE ESTABLISHMENT, APPROVAL, AND ENFORCEMENT OF ELECTRIC RELIABILITY STANDARDS § 39.4 Funding of the Electric Reliability Organization. (a) Any... Reliability Organization. 39.4 Section 39.4 Conservation of Power and Water Resources FEDERAL ENERGY...

  12. Electrical distribution system management

    International Nuclear Information System (INIS)

    Hajos, L.; Mortarulo, M.; Chang, K.; Sparks, T.

    1990-01-01

    This paper reports that maintenance of electrical system data is essential to the operation, maintenance, and modification of a nuclear station. Load and equipment changes affect equipment sizing, available short-circuit currents and protection coordination. System parameters must be maintained in a controlled manner to enable evaluation of proposed modifications and provide adequate verification and traceability. For this purpose, Public Service Electric and Gas Company has implemented a Verified and Validated Electric Distribution System Management (EDSM) program at the Hope Creek and Salem Nuclear Power Stations. EDSM program integrates computerized configuration management of electrical systems with calculational software the Technical Standard procedures. The software platform is PC-based. The Database Manager and Calculational programs have been linked together through a user friendly menu system. The database management nodule enable s assembly and maintenance of databases for individual loads, buses, and branches within the electrical systems with system access and approval controlled through electronic security incorporated within the database manger. Reports drawn from the database serve as the as-built and/or as-designed record of the system configurations. This module also creates input data files of network parameters in a format readable by the calculational modules. Calculations modules provide load flow, voltage drop, motor starting, and short-circuit analyses, as well as dynamic analyses of bus transfers

  13. Flexibility and reliability in long-term planning exercises dedicated to the electricity sector

    Energy Technology Data Exchange (ETDEWEB)

    Maizi, Nadia; Drouineau, Mathilde; Assoumou, Edi; Mazauric, Vincent

    2010-09-15

    Long-term planning models are useful to build plausible options for future energy systems and must consequently address the technological feasibility and associated cost of these options. This paper focuses on the electricity sector and on problems of flexibility and reliability in power systems in order to improve results provided by long-term planning exercises: flexibility needs are integrated as an additional criterion for new investment decisions and, reliability requirements are assessed through the level of electrical losses they induced and a related cost. These approaches are implemented in a long-term planning model and demonstrated through a study of the Reunion Island.

  14. A physical review on power system reliability factors

    International Nuclear Information System (INIS)

    Navid, Taghizadegan; Ahmad Reza, Zentabchi; Mohammad Ali, Tavakoli; Nader, Samsunchi; Mohammad Ali, Tavakoli

    2005-01-01

    Full text : Planning and design engineers and management must necessarily take into consideration the funds available, the requirements of regulatory agencies and other restrictions that may be imposed, as well as availability of equipment and supplies. A well-designed electrical power system strikes a reasonable between reliability and cost. A prime responsibility of power system operators is to operate their systems in such a way that will provide the maximum reliability of service possible with the facilities under their control

  15. Reliability models for Space Station power system

    Science.gov (United States)

    Singh, C.; Patton, A. D.; Kim, Y.; Wagner, H.

    1987-01-01

    This paper presents a methodology for the reliability evaluation of Space Station power system. The two options considered are the photovoltaic system and the solar dynamic system. Reliability models for both of these options are described along with the methodology for calculating the reliability indices.

  16. Demand Response as a System Reliability Resource

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Lewis, Nancy Jo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Watson, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Auslander, David [Univ. of California, Berkeley, CA (United States); Paprotny, Igor [Univ. of California, Berkeley, CA (United States); Makarov, Yuri [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-12-31

    The Demand Response as a System Reliability Resource project consists of six technical tasks: • Task 2.1. Test Plan and Conduct Tests: Contingency Reserves Demand Response (DR) Demonstration—a pioneering demonstration of how existing utility load-management assets can provide an important electricity system reliability resource known as contingency reserve. • Task 2.2. Participation in Electric Power Research Institute (EPRI) IntelliGrid—technical assistance to the EPRI IntelliGrid team in developing use cases and other high-level requirements for the architecture. • Task 2.3. Research, Development, and Demonstration (RD&D) Planning for Demand Response Technology Development—technical support to the Public Interest Energy Research (PIER) Program on five topics: Sub-task 1. PIER Smart Grid RD&D Planning Document; Sub-task 2. System Dynamics of Programmable Controllable Thermostats; Sub-task 3. California Independent System Operator (California ISO) DR Use Cases; Sub-task 4. California ISO Telemetry Requirements; and Sub-task 5. Design of a Building Load Data Storage Platform. • Task 2.4. Time Value of Demand Response—research that will enable California ISO to take better account of the speed of the resources that it deploys to ensure compliance with reliability rules for frequency control. • Task 2.5. System Integration and Market Research: Southern California Edison (SCE)—research and technical support for efforts led by SCE to conduct demand response pilot demonstrations to provide a contingency reserve service (known as non-spinning reserve) through a targeted sub-population of aggregated residential and small commercial customers enrolled in SCE’s traditional air conditioning (AC) load cycling program, the Summer Discount Plan. • Task 2.6. Demonstrate Demand Response Technologies: Pacific Gas and Electric (PG&E)—research and technical support for efforts led by PG&E to conduct a demand response pilot demonstration to provide non

  17. Survey of aircraft electrical power systems

    Science.gov (United States)

    Lee, C. H.; Brandner, J. J.

    1972-01-01

    Areas investigated include: (1) load analysis; (2) power distribution, conversion techniques and generation; (3) design criteria and performance capabilities of hydraulic and pneumatic systems; (4) system control and protection methods; (5) component and heat transfer systems cooling; and (6) electrical system reliability.

  18. Towards Reliable Integrated Services for Dependable Systems

    DEFF Research Database (Denmark)

    Schiøler, Henrik; Ravn, Anders Peter; Izadi-Zamanabadi, Roozbeh

    Reliability issues for various technical systems are discussed and focus is directed towards distributed systems, where communication facilities are vital to maintain system functionality. Reliability in communication subsystems is considered as a resource to be shared among a number of logical c...... applications residing on alternative routes. Details are provided for the operation of RRRSVP based on reliability slack calculus. Conclusions summarize the considerations and give directions for future research....... connections and a reliability management framework is suggested. We suggest a network layer level reliability management protocol RRSVP (Reliability Resource Reservation Protocol) as a counterpart of the RSVP for bandwidth and time resource management. Active and passive standby redundancy by background...

  19. Towards Reliable Integrated Services for Dependable Systems

    DEFF Research Database (Denmark)

    Schiøler, Henrik; Ravn, Anders Peter; Izadi-Zamanabadi, Roozbeh

    2003-01-01

    Reliability issues for various technical systems are discussed and focus is directed towards distributed systems, where communication facilities are vital to maintain system functionality. Reliability in communication subsystems is considered as a resource to be shared among a number of logical c...... applications residing on alternative routes. Details are provided for the operation of RRRSVP based on reliability slack calculus. Conclusions summarize the considerations and give directions for future research....... connections and a reliability management framework is suggested. We suggest a network layer level reliability management protocol RRSVP (Reliability Resource Reservation Protocol) as a counterpart of the RSVP for bandwidth and time resource management. Active and passive standby redundancy by background...

  20. Electrical railway transportation systems

    CERN Document Server

    Brenna, Morris; Zaninelli, Dario

    2018-01-01

    Allows the reader to deepen their understanding of various technologies for both fixed power supply installations of railway systems and for railway rolling stock. This book explores the electric railway systems that play a crucial role in the mitigation of congestion and pollution caused by road traffic. It is divided into two parts: the first covering fixed power supply systems, and the second concerning the systems for railway rolling stock. In particular, after a historical introduction to the framework of technological solutions in current use, the authors investigate electrification systems for the power supply of rail vehicles, trams, and subways. Electrical Railway Transportation Systems explores the direct current systems used throughout the world for urban and suburban transport, which are also used in various countries for regional transport. It provides a study of alternating current systems, whether for power supply frequency or for special railway frequency, that are used around the world for ...

  1. Electrical energy systems

    CERN Document Server

    El-Hawary, Mohamed E

    2007-01-01

    Features discussions ranging from the technical aspects of generation, transmission, distribution, and utilization to power system components, theory, protection, and the energy control center that offer an introduction to effects of deregulating electric power systems, blackouts and their causes, and minimizing their effects.

  2. Selection, design, qualification, testing, and reliability of emergency diesel generator units used as Class 1E onsite electric power systems at nuclear power plants

    International Nuclear Information System (INIS)

    1992-04-01

    This guide has been prepared for the resolution of Generic Safety Issue B-56, ''Diesel Generator Reliability,'' and is related to Unresolved Safety Issue (USI) A-44, ''Station Blackout.'' The resolution of USI A-44 established a need for an emergency diesel generator (EDG) reliability program that has the capability to achieve and maintain the emergency diesel generator reliability levels in the range of 0.95 per demand or better to cope with station blackout

  3. Advances in reliability and system engineering

    CERN Document Server

    Davim, J

    2017-01-01

    This book presents original studies describing the latest research and developments in the area of reliability and systems engineering. It helps the reader identifying gaps in the current knowledge and presents fruitful areas for further research in the field. Among others, this book covers reliability measures, reliability assessment of multi-state systems, optimization of multi-state systems, continuous multi-state systems, new computational techniques applied to multi-state systems and probabilistic and non-probabilistic safety assessment.

  4. Reliability of Power Electronic Converter Systems

    DEFF Research Database (Denmark)

    -link capacitance in power electronic converter systems; wind turbine systems; smart control strategies for improved reliability of power electronics system; lifetime modelling; power module lifetime test and state monitoring; tools for performance and reliability analysis of power electronics systems; fault...... for advancing the reliability, availability, system robustness, and maintainability of PECS at different levels of complexity. Drawing on the experience of an international team of experts, this book explores the reliability of PECS covering topics including an introduction to reliability engineering in power...... electronic converter systems; anomaly detection and remaining-life prediction for power electronics; reliability of DC-link capacitors in power electronic converters; reliability of power electronics packaging; modeling for life-time prediction of power semiconductor modules; minimization of DC...

  5. Reliability and optimization of structural systems

    International Nuclear Information System (INIS)

    Thoft-Christensen, P.

    1987-01-01

    The proceedings contain 28 papers presented at the 1st working conference. The working conference was organized by the IFIP Working Group 7.5. The proceedings also include 4 papers which were submitted, but for various reasons not presented at the working conference. The working conference was attended by 50 participants from 18 countries. The conference was the first scientific meeting of the new IFIP Working Group 7.5 on 'Reliability and Optimization of Structural Systems'. The purpose of the Working Group 7.5 is to promote modern structural system optimization and reliability theory, to advance international cooperation in the field of structural system optimization and reliability theory, to stimulate research, development and application of structural system optimization and reliability theory, to further the dissemination and exchange of information on reliability and optimization of structural system optimization and reliability theory, and to encourage education in structural system optimization and reliability theory. (orig./HP)

  6. Reliable CPS design for mitigating semiconductor and battery aging in electric vehicles

    NARCIS (Netherlands)

    Chang, W.; Proebstl, A.; Goswami, D.; Zamani, M.; Chakraborty, S.

    2015-01-01

    Reliability and performance of cyber-physical systems (CPS) in electric vehicles (EVs) are influenced by three design aspects: (i) controller design, (ii) battery usage, i.e., Battery rate capacity and aging effects, (iii) processor aging of the in-vehicle embedded platform. In this paper, we

  7. Evaluation of conventional electric power generating industry quality assurance and reliability practices

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R.T.; Lauffenburger, H.A.

    1981-03-01

    The techniques and practices utilized in an allied industry (electric power generation) that might serve as a baseline for formulating Quality Assurance and Reliability (QA and R) procedures for photovoltaic solar energy systems were studied. The study results provide direct near-term input for establishing validation methods as part of the SERI performance criteria and test standards development task.

  8. Designing incentive market mechanisms for improving restructured power system reliabilities

    DEFF Research Database (Denmark)

    Ding, Yi; Østergaard, Jacob; Wu, Qiuwei

    2011-01-01

    state. The reliability management of producers usually cannot be directly controlled by the system operators in a restructured power system. Producers may have no motivation to improve their reliabilities, which can result in serious system unreliability issues in the new environment. Incentive market...... mechanisms for improving the restructured power system reliabilities have been designed in this paper. In the proposed incentive mechanisms, penalty will be implemented on a producer if the failures of its generator(s) result in the variation of electricity prices. Incentive market mechanisms can motivate......In a restructured power system, the monopoly generation utility is replaced by different electricity producers. There exists extreme price volatility caused by random failures by generation or/and transmission systems. In these cases, producers' profits can be much higher than those in the normal...

  9. Study of aircraft electrical power systems

    Science.gov (United States)

    1972-01-01

    The formulation of a philosophy for devising a reliable, efficient, lightweight, and cost effective electrical power system for advanced, large transport aircraft in the 1980 to 1985 time period is discussed. The determination and recommendation for improvements in subsystems and components are also considered. All aspects of the aircraft electrical power system including generation, conversion, distribution, and utilization equipment were considered. Significant research and technology problem areas associated with the development of future power systems are identified. The design categories involved are: (1) safety-reliability, (2) power type, voltage, frequency, quality, and efficiency, (3) power control, and (4) selection of utilization equipment.

  10. Reliable control system for nuclear power plant

    International Nuclear Information System (INIS)

    Okamoto, Tetsuo; Miyazaki, Shiro

    1980-01-01

    The System 1100 for nuclear power plants is the measuring and control system which utilizes the features of the System 1100 for electric power market in addition to the results of nuclear instrumentation with EBS-ZN series, and it has the following features. The maintenance and inspection in operation are easy. The construction of control loops is made flexibly by the combination of modules. The construction of multi-variable control system using mainly feed forward control is easy. Such functions as the automatic switching of control modes can be included. The switching of manual and automatic operations is easy, and if some trouble occurred in a module, the manual operation can be made. The aseismatic ability is improved by rigid structure cubicles. Nonflammable materials are used for wires, multi-core cables, paints and printed boards. The anti-noise characteristics are improved, and the reliability is high. The policy of developing the System 1100 for nuclear power plants, the type approval tests on modules and units and the type approval test on the system are described. The items of the system type approval test were standard performance test, earthquake test, noise isolation test, temperature and humidity test, and drift test. The aseismatic cubicle showed good endurance in its vibration test. (Kako, I.)

  11. Reliable actuators for twin rotor MIMO system

    Science.gov (United States)

    Rao, Vidya S.; V. I, George; Kamath, Surekha; Shreesha, C.

    2017-11-01

    Twin Rotor MIMO System (TRMS) is a bench mark system to test flight control algorithms. One of the perturbations on TRMS which is likely to affect the control system is actuator failure. Therefore, there is a need for a reliable control system, which includes H infinity controller along with redundant actuators. Reliable control refers to the design of a control system to tolerate failures of a certain set of actuators or sensors while retaining desired control system properties. Output of reliable controller has to be transferred to the redundant actuator effectively to make the TRMS reliable even under actual actuator failure.

  12. Electric power systems

    CERN Document Server

    Weedy, B M; Jenkins, N; Ekanayake, J B; Strbac, G

    2012-01-01

    The definitive textbook for Power Systems students, providing a grounding in essential power system theory while also focusing on practical power engineering applications. Electric Power Systems has been an essential book in power systems engineering for over thirty years. Bringing the content firmly up-to-date whilst still retaining the flavour of Weedy's extremely popular original, this Fifth Edition has been revised by experts Nick Jenkins, Janaka Ekanayake and Goran Strbac. This wide-ranging text still covers all of the fundamental power systems subjects but is now e

  13. 18 CFR 375.303 - Delegations to the Director of the Office of Electric Reliability.

    Science.gov (United States)

    2010-04-01

    ... Director of the Office of Electric Reliability. 375.303 Section 375.303 Conservation of Power and Water... Delegations § 375.303 Delegations to the Director of the Office of Electric Reliability. The Commission... Electric Reliability Organization or Regional Entity rules or procedures; (ii) Reject an application...

  14. 18 CFR 39.10 - Changes to an Electric Reliability Organization Rule or Regional Entity Rule.

    Science.gov (United States)

    2010-04-01

    ... RULES CONCERNING CERTIFICATION OF THE ELECTRIC RELIABILITY ORGANIZATION; AND PROCEDURES FOR THE ESTABLISHMENT, APPROVAL, AND ENFORCEMENT OF ELECTRIC RELIABILITY STANDARDS § 39.10 Changes to an Electric... Reliability Organization Rule or Regional Entity Rule. 39.10 Section 39.10 Conservation of Power and Water...

  15. Research on reliability management systems for Nuclear Power Plant

    International Nuclear Information System (INIS)

    Maki, Nobuo

    2000-01-01

    Investigation on a reliability management system for Nuclear Power Plants (NPPs) has been performed on national and international archived documents as well as on current status of studies at Idaho National Engineering and Environmental Laboratory (INEEL), US NPPs (McGuire, Seabrook), a French NPP (St. Laurent-des-Eaux), Japan Atomic Energy Research Institute (JAERI), Central Research Institute of Electric Power Industries (CRIEPI), and power plant manufacturers in Japan. As a result of the investigation, the following points were identified: (i) A reliability management system is composed of a maintenance management system to inclusively manage maintenance data, and an anomalies information and reliability data management system to extract data from maintenance results stored in the maintenance management system and construct a reliability database. (ii) The maintenance management system, which is widely-used among NPPs in the US and Europe, is an indispensable system for the increase of maintenance reliability. (iii) Maintenance management methods utilizing reliability data like Reliability Centered Maintenance are applied for NPP maintenance in the US and Europe, and contributing to cost saving. Maintenance templates are effective in the application process. In addition, the following points were proposed on the design of the system: (i) A detailed database on specifications of facilities and components is necessary for the effective use of the system. (ii) A demand database is indispensable for the application of the methods. (iii) Full-time database managers are important to maintain the quality of the reliability data. (author)

  16. System Reliability Analysis Considering Correlation of Performances

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Saekyeol; Lee, Tae Hee [Hanyang Univ., Seoul (Korea, Republic of); Lim, Woochul [Mando Corporation, Seongnam (Korea, Republic of)

    2017-04-15

    Reliability analysis of a mechanical system has been developed in order to consider the uncertainties in the product design that may occur from the tolerance of design variables, uncertainties of noise, environmental factors, and material properties. In most of the previous studies, the reliability was calculated independently for each performance of the system. However, the conventional methods cannot consider the correlation between the performances of the system that may lead to a difference between the reliability of the entire system and the reliability of the individual performance. In this paper, the joint probability density function (PDF) of the performances is modeled using a copula which takes into account the correlation between performances of the system. The system reliability is proposed as the integral of joint PDF of performances and is compared with the individual reliability of each performance by mathematical examples and two-bar truss example.

  17. System Reliability Analysis Considering Correlation of Performances

    International Nuclear Information System (INIS)

    Kim, Saekyeol; Lee, Tae Hee; Lim, Woochul

    2017-01-01

    Reliability analysis of a mechanical system has been developed in order to consider the uncertainties in the product design that may occur from the tolerance of design variables, uncertainties of noise, environmental factors, and material properties. In most of the previous studies, the reliability was calculated independently for each performance of the system. However, the conventional methods cannot consider the correlation between the performances of the system that may lead to a difference between the reliability of the entire system and the reliability of the individual performance. In this paper, the joint probability density function (PDF) of the performances is modeled using a copula which takes into account the correlation between performances of the system. The system reliability is proposed as the integral of joint PDF of performances and is compared with the individual reliability of each performance by mathematical examples and two-bar truss example.

  18. Thermal Management and Reliability of Power Electronics and Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, Sreekant

    2016-08-03

    Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil -- by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, and in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines will be presented.

  19. Thermal Management and Reliability of Power Electronics and Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, Sreekant

    2016-06-13

    Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil - by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, and in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines are presented.

  20. Fundamentals and applications of systems reliability analysis

    International Nuclear Information System (INIS)

    Boesebeck, K.; Heuser, F.W.; Kotthoff, K.

    1976-01-01

    The lecture gives a survey on the application of methods of reliability analysis to assess the safety of nuclear power plants. Possible statements of reliability analysis in connection with specifications of the atomic licensing procedure are especially dealt with. Existing specifications of safety criteria are additionally discussed with the help of reliability analysis by the example of the reliability analysis of a reactor protection system. Beyond the limited application to single safety systems, the significance of reliability analysis for a closed risk concept is explained in the last part of the lecture. (orig./LH) [de

  1. Overview of system reliability analyses for PSA

    International Nuclear Information System (INIS)

    Matsuoka, Takeshi

    2012-01-01

    Overall explanations are given for many matters relating to system reliability analysis. Systems engineering, Operations research, Industrial engineering, Quality control are briefly explained. Many system reliability analysis methods including advanced methods are introduced. Discussions are given for FMEA, reliability block diagram, Markov model, Petri net, Bayesian network, goal tree success tree, dynamic flow graph methodology, cell-to-cell mapping technique, the GO-FLOW and others. (author)

  2. System reliability effects in wind turbine blades

    DEFF Research Database (Denmark)

    Dimitrov, Nikolay Krasimirov; Friis-Hansen, Peter; Berggreen, Christian

    2012-01-01

    from reliability point of view. The present paper discusses the specifics of system reliability behavior of laminated composite sandwich panels, and solves an example system reliability problem for a glass fiber-reinforced composite sandwich structure subjected to in-plane compression.......Laminated composite sandwich panels have a layered structure, where individual layers have randomly varying stiffness and strength properties. The presence of multiple failure modes and load redistribution following partial failures are the reason for laminated composites to exhibit system behavior...

  3. ASCERTAINMENT OF ELECTRIC-SUPPLY SCHEMES RELIABILITY FOR THE ATOMIC POWER PLANT AUXILIARIES

    Directory of Open Access Journals (Sweden)

    A. L. Starzhinskij

    2015-01-01

    Full Text Available The paper completes ascertainment of electrical-supply scheme reliability for the auxiliaries of a nuclear power plant. Thereat the author considers the system behavior during the block normal operation, carrying out current maintenance, and capital repairs in combination with initiating events. The initiating events for reactors include complete blackout, i.e. the loss of outside power supply (normal and reserve; emergency switching one of the working turbogenerators; momentary dumping the normal rating to the level of auxiliaries with seating the cutout valve of one turbo-generator. The combination of any initiating event with the repairing mode in case of one of the system elements failure should not lead to blackout occurrence of more than one system of the reliable power supply. This requirement rests content with the help of the reliable power supply system self-dependence (electrical and functional and the emergency power-supply operational autonomy (diesel generator and accumulator batteries.The reliability indicators of the power supply system for the nuclear power plant auxiliaries are the conditional probabilities of conjoined blackout of one, two, and three sections of the reliable power supply conditional upon an initiating event emerging and the blackout of one, two, and three reliable power-supply sections under the normal operational mode. Furthermore, they also are the blackout periodicity of one and conjointly two, three, and four sections of normal operation under the block normal operational mode. It is established that the blackout of one bus section of normal operation and one section of reliable power-supply system of the auxiliaries that does not lead to complete blackout of the plant auxiliaries may occur once in three years. The probability of simultaneous power failure of two or three normal-operation sections and of two reliable power-supply sections during the power plant service life is unlikely.

  4. French power system reliability report 2008

    International Nuclear Information System (INIS)

    Tesseron, J.M.

    2009-06-01

    The reliability of the French power system was fully under control in 2008, despite the power outage in the eastern part of the Provence-Alpes-Cote d'Azur region on November 3, which had been dreaded for several years, since it had not been possible to set up a structurally adequate network. Pursuant to a consultation meeting, the reinforcement solution proposed by RTE was approved by the Minister of Energy, boding well for greater reliability in future. Based on the observations presented in this 2008 Report, RTE's Power System Reliability Audit Mission considers that no new recommendations are needed beyond those expressed in previous reliability reports and during reliability audits. The publication of this yearly report is in keeping with RTE's goal to promote the follow-up over time of the evolution of reliability in its various aspects. RTE thus aims to contribute to the development of reliability culture, by encouraging an improved assessment by the different players (both RTE and network users) of the role they play in building reliability, and by advocating the taking into account of reliability and benchmarking in the European organisations of Transmission System Operators. Contents: 1 - Brief overview of the evolution of the internal and external environment; 2 - Operating situations encountered: climatic conditions, supply / demand balance management, operation of interconnections, management of internal congestion, contingencies affecting the transmission facilities; 3 - Evolution of the reliability reference guide: external reference guide: directives, laws, decrees, etc, ETSO, UCTE, ENTSO-E, contracting contributing to reliability, RTE internal reference guide; 4 - Evolution of measures contributing to reliability in the equipment field: intrinsic performances of components (generating sets, protection systems, operation PLC's, instrumentation and control, automatic frequency and voltage controls, transmission facilities, control systems, load

  5. Estimated Value of Service Reliability for Electric Utility Customers in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, M.J.; Mercurio, Matthew; Schellenberg, Josh

    2009-06-01

    Information on the value of reliable electricity service can be used to assess the economic efficiency of investments in generation, transmission and distribution systems, to strategically target investments to customer segments that receive the most benefit from system improvements, and to numerically quantify the risk associated with different operating, planning and investment strategies. This paper summarizes research designed to provide estimates of the value of service reliability for electricity customers in the US. These estimates were obtained by analyzing the results from 28 customer value of service reliability studies conducted by 10 major US electric utilities over the 16 year period from 1989 to 2005. Because these studies used nearly identical interruption cost estimation or willingness-to-pay/accept methods it was possible to integrate their results into a single meta-database describing the value of electric service reliability observed in all of them. Once the datasets from the various studies were combined, a two-part regression model was used to estimate customer damage functions that can be generally applied to calculate customer interruption costs per event by season, time of day, day of week, and geographical regions within the US for industrial, commercial, and residential customers. Estimated interruption costs for different types of customers and of different duration are provided. Finally, additional research and development designed to expand the usefulness of this powerful database and analysis are suggested.

  6. Reliability of structural systems subject to fatigue

    International Nuclear Information System (INIS)

    Rackwitz, R.

    1984-01-01

    Concepts and computational procedures for the reliability calculation of structural systems subject to fatigue are outlined. Systems are dealt with by approximately computing componential times to first failure. So-called first-order reliability methods are then used to formulate dependencies between componential failures and to evaluate the system failure probability. (Author) [pt

  7. Exact reliability quantification of highly reliable systems with maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Bris, Radim, E-mail: radim.bris@vsb.c [VSB-Technical University Ostrava, Faculty of Electrical Engineering and Computer Science, Department of Applied Mathematics, 17. listopadu 15, 70833 Ostrava-Poruba (Czech Republic)

    2010-12-15

    When a system is composed of highly reliable elements, exact reliability quantification may be problematic, because computer accuracy is limited. Inaccuracy can be due to different aspects. For example, an error may be made when subtracting two numbers that are very close to each other, or at the process of summation of many very different numbers, etc. The basic objective of this paper is to find a procedure, which eliminates errors made by PC when calculations close to an error limit are executed. Highly reliable system is represented by the use of directed acyclic graph which is composed from terminal nodes, i.e. highly reliable input elements, internal nodes representing subsystems and edges that bind all of these nodes. Three admissible unavailability models of terminal nodes are introduced, including both corrective and preventive maintenance. The algorithm for exact unavailability calculation of terminal nodes is based on merits of a high-performance language for technical computing MATLAB. System unavailability quantification procedure applied to a graph structure, which considers both independent and dependent (i.e. repeatedly occurring) terminal nodes is based on combinatorial principle. This principle requires summation of a lot of very different non-negative numbers, which may be a source of an inaccuracy. That is why another algorithm for exact summation of such numbers is designed in the paper. The summation procedure uses benefits from a special number system with the base represented by the value 2{sup 32}. Computational efficiency of the new computing methodology is compared with advanced simulation software. Various calculations on systems from references are performed to emphasize merits of the methodology.

  8. NSTX Electrical Power Systems

    International Nuclear Information System (INIS)

    A. Ilic; E. Baker; R. Hatcher; S. Ramakrishnan; et al

    1999-01-01

    The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physic Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. The design of the NSTX electrical power system was tailored to suit the available infrastructure and electrical equipment on site. Components were analyzed to verify their suitability for use in NSTX. The total number of circuits and the location of the NSTX device drove the major changes in the Power system hardware. The NSTX has eleven (11) circuits to be fed as compared to the basic three power loops for TFTR. This required changes in cabling to insure that each cable tray system has the positive and negative leg of cables in the same tray. Also additional power cabling had to be installed to the new location. The hardware had to b e modified to address the need for eleven power loops. Power converters had to be reconnected and controlled in anti-parallel mode for the Ohmic heating and two of the Poloidal Field circuits. The circuit for the Coaxial Helicity Injection (CHI) System had to be carefully developed to meet this special application. Additional Protection devices were designed and installed for the magnet coils and the CHI. The thrust was to making the changes in the most cost-effective manner without compromising technical requirements. This paper describes the changes and addition to the Electrical Power System components for the NSTX magnet systems

  9. Electric Power Infrastructure Reliability And Security Research And Development Initiative. Final report

    International Nuclear Information System (INIS)

    Dale, S.; Meeker, R.; Steurer, M.; Li, H.; Pamidi, S.; Rodrigo, H.; Suryanarayanan, S.; Cartes, D.; Ordonez, J.; Domijan, A.; Liu, W.; Cox, D.; McLaren, P.; Hovsapian, R.; Edwards, D.; Simmons, S.; Wilde, N.; Woodruff, S.; Kopriva, D.; Hussaini, Y.; Mohammed, O.; Zheng, J.; Baldwin, T.L.

    2008-01-01

    This is the final scientific/technical report for the Electric Power Infrastructure Reliability and Security R and D Initiative sponsored by the U.S. Department of Energy, Office of Electricity Delivery and Energy Reliability, under award number DE-FG02-05CH11292. This report covers results from the FSU-led, multi-institution effort conducted over the period 8/15/05 to 10/14/2007. Building upon existing infrastructure for power systems research, modeling, and simulation, the Center for Advanced Power Systems (CAPS) at Florida State University (FSU) is developing world-class programs in electric power systems research and education to support future electric power system needs and challenges. With U.S. Department of Energy Support, FSU CAPS has engaged in a multi-faceted effort to conduct basic and applied research towards understanding, developing, and deploying technologies and approaches that can lead to improved reliability and security of the North American electric power generation and delivery infrastructure. This wide-reaching project, through a number of carefully selected thrusts cutting across several research disciplines, set out to address key terrestrial electric utility power system issues and challenges. The challenges and the thrusts to address them were arrived at through analysis of a number of national reports and recommendations combined with input from an experienced multi-disciplined team of power systems research staff and faculty at FSU CAPS. The resulting project effort can be grouped into four major areas: - Power Systems and New Technology Insertion - Controls, Protection, and Security - Simulation Development - High Temperature Superconductivity (HTS)

  10. Solid State Lighting Reliability Components to Systems

    CERN Document Server

    Fan, XJ

    2013-01-01

    Solid State Lighting Reliability: Components to Systems begins with an explanation of the major benefits of solid state lighting (SSL) when compared to conventional lighting systems including but not limited to long useful lifetimes of 50,000 (or more) hours and high efficacy. When designing effective devices that take advantage of SSL capabilities the reliability of internal components (optics, drive electronics, controls, thermal design) take on critical importance. As such a detailed discussion of reliability from performance at the device level to sub components is included as well as the integrated systems of SSL modules, lamps and luminaires including various failure modes, reliability testing and reliability performance. This book also: Covers the essential reliability theories and practices for current and future development of Solid State Lighting components and systems Provides a systematic overview for not only the state-of-the-art, but also future roadmap and perspectives of Solid State Lighting r...

  11. Structural Reliability Methods for Wind Power Converter System Component Reliability Assessment

    DEFF Research Database (Denmark)

    Kostandyan, Erik; Sørensen, John Dalsgaard

    2012-01-01

    Wind power converter systems are essential subsystems in both off-shore and on-shore wind turbines. It is the main interface between generator and grid connection. This system is affected by numerous stresses where the main contributors might be defined as vibration and temperature loadings....... The temperature variations induce time-varying stresses and thereby fatigue loads. A probabilistic model is used to model fatigue failure for an electrical component in the power converter system. This model is based on a linear damage accumulation and physics of failure approaches, where a failure criterion...... is defined by the threshold model. The attention is focused on crack propagation in solder joints of electrical components due to the temperature loadings. Structural Reliability approaches are used to incorporate model, physical and statistical uncertainties. Reliability estimation by means of structural...

  12. Reliability of large and complex systems

    CERN Document Server

    Kolowrocki, Krzysztof

    2014-01-01

    Reliability of Large and Complex Systems, previously titled Reliability of Large Systems, is an innovative guide to the current state and reliability of large and complex systems. In addition to revised and updated content on the complexity and safety of large and complex mechanisms, this new edition looks at the reliability of nanosystems, a key research topic in nanotechnology science. The author discusses the importance of safety investigation of critical infrastructures that have aged or have been exposed to varying operational conditions. This reference provides an asympt

  13. Electric markets and services of the system

    International Nuclear Information System (INIS)

    Carbajo, A.

    2007-01-01

    Electricity cannot be stored in significant quantities and requires generation and demand be balanced instantly in order to control the frequency. This means that the electric system must be equipped with specific devices in order to ensure this dynamic balance. Of the services required by the electric system, some are mandatory for the generators, while others are voluntary, these last ones being those supplied under market schemes. On the other hand, the commitment of the Spanish electric system to incorporate a significant volume of renewable energy, due to its intermittent properties, demands that these adjustment services use a greater volume of this energy in order to ensure the reliability of the system at all times. Finally, securing the Iberian electric market implies that there might be variations in these services - not only in the volume but also in their characteristics. (Author)

  14. Reliability measurement for mixed mode failures of 33/11 kilovolt electric power distribution stations.

    Directory of Open Access Journals (Sweden)

    Faris M Alwan

    Full Text Available The reliability of the electrical distribution system is a contemporary research field due to diverse applications of electricity in everyday life and diverse industries. However a few research papers exist in literature. This paper proposes a methodology for assessing the reliability of 33/11 Kilovolt high-power stations based on average time between failures. The objective of this paper is to find the optimal fit for the failure data via time between failures. We determine the parameter estimation for all components of the station. We also estimate the reliability value of each component and the reliability value of the system as a whole. The best fitting distribution for the time between failures is a three parameter Dagum distribution with a scale parameter [Formula: see text] and shape parameters [Formula: see text] and [Formula: see text]. Our analysis reveals that the reliability value decreased by 38.2% in each 30 days. We believe that the current paper is the first to address this issue and its analysis. Thus, the results obtained in this research reflect its originality. We also suggest the practicality of using these results for power systems for both the maintenance of power systems models and preventive maintenance models.

  15. Automated Energy Distribution and Reliability System Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Buche, D. L.; Perry, S.

    2007-10-01

    This report describes Northern Indiana Public Service Co. project efforts to develop an automated energy distribution and reliability system. The purpose of this project was to implement a database-driven GIS solution that would manage all of the company's gas, electric, and landbase objects.

  16. Automated Energy Distribution and Reliability System (AEDR): Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Buche, D. L.

    2008-07-01

    This report describes Northern Indiana Public Service Co. project efforts to develop an automated energy distribution and reliability system. The purpose of this project was to implement a database-driven GIS solution that would manage all of the company's gas, electric, and landbase objects.

  17. Reliability modeling and analysis of smart power systems

    CERN Document Server

    Karki, Rajesh; Verma, Ajit Kumar

    2014-01-01

    The volume presents the research work in understanding, modeling and quantifying the risks associated with different ways of implementing smart grid technology in power systems in order to plan and operate a modern power system with an acceptable level of reliability. Power systems throughout the world are undergoing significant changes creating new challenges to system planning and operation in order to provide reliable and efficient use of electrical energy. The appropriate use of smart grid technology is an important drive in mitigating these problems and requires considerable research acti

  18. R&D program benefits estimation: DOE Office of Electricity Delivery and Energy Reliability

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2006-12-04

    The overall mission of the U.S. Department of Energy’s Office of Electricity Delivery and Energy Reliability (OE) is to lead national efforts to modernize the electric grid, enhance the security and reliability of the energy infrastructure, and facilitate recovery from disruptions to the energy supply. In support of this mission, OE conducts a portfolio of research and development (R&D) activities to advance technologies to enhance electric power delivery. Multiple benefits are anticipated to result from the deployment of these technologies, including higher quality and more reliable power, energy savings, and lower cost electricity. In addition, OE engages State and local government decision-makers and the private sector to address issues related to the reliability and security of the grid, including responding to national emergencies that affect energy delivery. The OE R&D activities are comprised of four R&D lines: High Temperature Superconductivity (HTS), Visualization and Controls (V&C), Energy Storage and Power Electronics (ES&PE), and Distributed Systems Integration (DSI).

  19. Reliability Based Optimization of Structural Systems

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    1987-01-01

    The optimization problem to design structural systems such that the reliability is satisfactory during the whole lifetime of the structure is considered in this paper. Some of the quantities modelling the loads and the strength of the structure are modelled as random variables. The reliability...... is estimated using first. order reliability methods ( FORM ). The design problem is formulated as the optimization problem to minimize a given cost function such that the reliability of the single elements satisfies given requirements or such that the systems reliability satisfies a given requirement....... For these optimization problems it is described how a sensitivity analysis can be performed. Next, new optimization procedures to solve the optimization problems are presented. Two of these procedures solve the system reliability based optimization problem sequentially using quasi-analytical derivatives. Finally...

  20. 78 FR 73112 - Monitoring System Conditions-Transmission Operations Reliability Standards; Interconnection...

    Science.gov (United States)

    2013-12-05

    ...\\ \\8\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, 72 FR 16416 (Apr. 4... operators and reliability coordinators to ``plan and operate the interconnected Bulk Electric System in a... mandated in the currently- effective standards, thereby improving reliability of the bulk power system...

  1. Optimizing electrical distribution systems

    International Nuclear Information System (INIS)

    Scott, W.G.

    1990-01-01

    Electrical utility distribution systems are in the middle of an unprecedented technological revolution in planning, design, maintenance and operation. The prime movers of the revolution are the major economic shifts that affect decision making. The major economic influence on the revolution is the cost of losses (technical and nontechnical). The vehicle of the revolution is the computer, which enables decision makers to examine alternatives in greater depth and detail than their predecessors could. The more important elements of the technological revolution are: system planning, computers, load forecasting, analytical systems (primary systems, transformers and secondary systems), system losses and coming technology. The paper is directed towards the rather unique problems encountered by engineers of utilities in developing countries - problems that are being solved through high technology, such as the recent World Bank-financed engineering computer system for Sri Lanka. This system includes a DEC computer, digitizer, plotter and engineering software to model the distribution system via a digitizer, analyse the system and plot single-line diagrams. (author). 1 ref., 4 tabs., 6 figs

  2. Reliability of power electronic converter systems

    CERN Document Server

    Chung, Henry Shu-hung; Blaabjerg, Frede; Pecht, Michael

    2016-01-01

    This book outlines current research into the scientific modeling, experimentation, and remedial measures for advancing the reliability, availability, system robustness, and maintainability of Power Electronic Converter Systems (PECS) at different levels of complexity.

  3. Electricity supply. Older plants' impact on reliability and air quality

    International Nuclear Information System (INIS)

    England-Joseph, Judy A.; Adams, Charles M.; Wood, David G.; Feehan, Daniel J.; Veal, Howard F.; Skeen, John H. III; Koenigs, Melvin J.; Lichtenfeld, David I.; Seretakis, Pauline J.

    1990-09-01

    Life extension of fossil fuel plants is a relatively recent phenomenon; thus, utilities have little experience to demonstrate the longer-term operating reliability of plants with an extended service life. While utility industry officials and government and industry studies express optimism that these plants will continue to operate reliably, the officials and the studies also caution that it is too soon to determine how pursuing life extension will affect the reliability of the nation's electricity supply. According to DOE, the number of fossil fuel generating units' 30 years old or older is expected to increase from about 2,500 in 1989 to roughly 3,700 in 1998, increasing such plants' share of overall generating capacity from 13 percent in 1989 to 27 percent in 1998. EPA estimates that with existing air quality requirements, fossil fuel plant emissions will increase steadily during the coming decade. Proposed acid rain control legislation, which would affect many plants that may have their service life extended, would require utilities to significantly reduce emissions by the year 2000 but would allow utilities flexibility in deciding how and where to achieve the reductions. If such legislation is enacted, utilities generally are expected to find reducing emissions from existing plants more cost-effective than replacing them and to continue extending plants' service life. Officials of DOE and utility organizations expressed concern, however, that EPA could decide, as it did for one plant in 1988, that alterations made in extending the service life of plants exempted from the Clean Air Act would result in increased emissions and thus cause the altered plants to lose their exemption. According to the officials, the additional costs of achieving the Clean Air Act's standards could discourage some life extension projects. However, such decisions by EPA could also reduce the nation's total power plant emissions by eliminating an existing incentive to retain exempt

  4. Reliability Growth in Space Life Support Systems

    Science.gov (United States)

    Jones, Harry W.

    2014-01-01

    A hardware system's failure rate often increases over time due to wear and aging, but not always. Some systems instead show reliability growth, a decreasing failure rate with time, due to effective failure analysis and remedial hardware upgrades. Reliability grows when failure causes are removed by improved design. A mathematical reliability growth model allows the reliability growth rate to be computed from the failure data. The space shuttle was extensively maintained, refurbished, and upgraded after each flight and it experienced significant reliability growth during its operational life. In contrast, the International Space Station (ISS) is much more difficult to maintain and upgrade and its failure rate has been constant over time. The ISS Carbon Dioxide Removal Assembly (CDRA) reliability has slightly decreased. Failures on ISS and with the ISS CDRA continue to be a challenge.

  5. Telecommunications system reliability engineering theory and practice

    CERN Document Server

    Ayers, Mark L

    2012-01-01

    "Increasing system complexity require new, more sophisticated tools for system modeling and metric calculation. Bringing the field up to date, this book provides telecommunications engineers with practical tools for analyzing, calculating, and reporting availability, reliability, and maintainability metrics. It gives the background in system reliability theory and covers in-depth applications in fiber optic networks, microwave networks, satellite networks, power systems, and facilities management. Computer programming tools for simulating the approaches presented, using the Matlab software suite, are also provided"

  6. Systems Engineering of Electric and Hybrid Vehicles

    Science.gov (United States)

    Kurtz, D. W.; Levin, R. R.

    1986-01-01

    Technical paper notes systems engineering principles applied to development of electric and hybrid vehicles such that system performance requirements support overall program goal of reduced petroleum consumption. Paper discusses iterative design approach dictated by systems analyses. In addition to obvious peformance parameters of range, acceleration rate, and energy consumption, systems engineering also considers such major factors as cost, safety, reliability, comfort, necessary supporting infrastructure, and availability of materials.

  7. Embedded mechatronic systems 1 analysis of failures, predictive reliability

    CERN Document Server

    El Hami, Abdelkhalak

    2015-01-01

    In operation, mechatronics embedded systems are stressed by loads of different causes: climate (temperature, humidity), vibration, electrical and electromagnetic. These stresses in components which induce failure mechanisms should be identified and modeled for better control. AUDACE is a collaborative project of the cluster Mov'eo that address issues specific to mechatronic reliability embedded systems. AUDACE means analyzing the causes of failure of components of mechatronic systems onboard. The goal of the project is to optimize the design of mechatronic devices by reliability. The projec

  8. Systems reliability in high risk situations

    International Nuclear Information System (INIS)

    Hunns, D.M.

    1974-12-01

    A summary is given of five papers and the discussion of a seminar promoted by the newly-formed National Centre of Systems Reliability. The topics covered include hazard analysis, reliability assessment, and risk assessment in both nuclear and non-nuclear industries. (U.K.)

  9. Reliability and durability in solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Godolphin, D.

    1982-10-01

    The reliability and durability in solar energy systems for residential buildings is discussed. It is concluded that although strides have been made in design and manufacturing over the past years, the reliability and durability of the equipment depends on the proper installation. (MJF)

  10. Reliable computer systems design and evaluatuion

    CERN Document Server

    Siewiorek, Daniel

    2014-01-01

    Enhance your hardware/software reliabilityEnhancement of system reliability has been a major concern of computer users and designers ¦ and this major revision of the 1982 classic meets users' continuing need for practical information on this pressing topic. Included are case studies of reliablesystems from manufacturers such as Tandem, Stratus, IBM, and Digital, as well as coverage of special systems such as the Galileo Orbiter fault protection system and AT&T telephone switching processors.

  11. Reliability analysis of Angra I safety systems

    International Nuclear Information System (INIS)

    Oliveira, L.F.S. de; Soto, J.B.; Maciel, C.C.; Gibelli, S.M.O.; Fleming, P.V.; Arrieta, L.A.

    1980-07-01

    An extensive reliability analysis of some safety systems of Angra I, are presented. The fault tree technique, which has been successfully used in most reliability studies of nuclear safety systems performed to date is employed. Results of a quantitative determination of the unvailability of the accumulator and the containment spray injection systems are presented. These results are also compared to those reported in WASH-1400. (E.G.) [pt

  12. Reliability-Based Optimization of Series Systems of Parallel Systems

    DEFF Research Database (Denmark)

    Enevoldsen, I.; Sørensen, John Dalsgaard

    1993-01-01

    Reliability-based design of structural systems is considered. In particular, systems where the reliability model is a series system of parallel systems are treated. A sensitivity analysis for this class of problems is presented. Optimization problems with series systems of parallel systems...... optimization of series systems of parallel systems, but it is also efficient in reliability-based optimization of series systems in general....

  13. System reliability developments in structural engineering

    International Nuclear Information System (INIS)

    Moses, F.

    1982-01-01

    Two major limitations occur in present structural design code developments utilizing reliability theory. The notional system reliabilities may differ significantly from calibrated component reliabilities. Secondly, actual failures are often due to gross errors not reflected in most present code formats. A review is presented of system reliability methods and further new concepts are developed. The incremental load approach for identifying and expressing collapse modes is expanded by employing a strategy to identify and enumerate the significant structural collapse modes. It further isolates the importance of critical components in the system performance. Ductile and brittle component behavior and strength correlation is reflected in the system model and illustrated in several examples. Modal combinations for the system reliability are also reviewed. From these developments a system factor can be addended to component safety checking equations. Values may be derived from system behavior by substituting in a damage model which accounts for the response range from component failure to collapse. Other strategies are discussed which emphasize quality assurance during design and in-service inspection for components whose behavior is critical to the system reliability. (Auth.)

  14. IMPULSE CONTROL HYBRID ELECTRICAL SYSTEM

    Directory of Open Access Journals (Sweden)

    A. A. Lobaty

    2016-01-01

    Full Text Available This paper extends the recently introduced approach for modeling and solving the optimal control problem of fixedswitched mode DC-DC power converter. DCDC converters are a class of electric power circuits that used extensively in regulated DC power supplies, DC motor drives of different types, in Photovoltaic Station energy conversion and other applications due to its advantageous features in terms of size, weight and reliable performance. The main problem in controlling this type converters is in their hybrid nature as the switched circuit topology entails different modes of operation, each of it with its own associated linear continuous-time dynamics.This paper analyses the modeling and controller synthesis of the fixed-frequency buck DC-DC converter, in which the transistor switch is operated by a pulse sequence with constant frequency. In this case the regulation of the DC component of the output voltage is via the duty cycle. The optimization of the control system is based on the formation of the control signal at the output.It is proposed to solve the problem of optimal control of a hybrid system based on the formation of the control signal at the output of the controller, which minimizes a given functional integral quality, which is regarded as a linear quadratic Letov-Kalman functional. Search method of optimal control depends on the type of mathematical model of control object. In this case, we consider a linear deterministic model of the control system, which is common for the majority of hybrid electrical systems. For this formulation of the optimal control problem of search is a problem of analytical design of optimal controller, which has the analytical solution.As an example of the hybrid system is considered a step-down switching DC-DC converter, which is widely used in various electrical systems: as an uninterruptible power supply, battery charger for electric vehicles, the inverter in solar photovoltaic power plants.. A

  15. THE ANALYSIS OF STRUCTURAL RELIABILITY OF THE MAIN ELECTRIC CONNECTION CIRCUITS OF NUCLEAR POWER PLANTS

    Directory of Open Access Journals (Sweden)

    M. A. Korotkevich

    2017-01-01

    Full Text Available The reliability of the main circuit of electrical connections at a nuclear electric power plant that has two units with a capacity of 1,200 MW each has been determined. Reliability, economical, maneuverable properties of the atomic power plant under study are largely determined by its main circuit, so the choice of the circuit for the design and its status in the process of operation occur to be critical objectives. Main electrical connection circuits in nuclear electric power plants are selected on the basis of the schematic networks of the energy system and the land attached to the plant. The circuit of the connection of a nuclear power plant to the grid in the original normal operating modes at all stages of the construction of such a plant should provide the outcome of the full added capacity of a nuclear power plant and the preservation of its stability in the power system without the influence of the emergency system automatics when any outgoing transmission line is disabled. When selecting the main circuit the individual capacity of the installed units and their number are taken into account as well as the order of development of the plant and power supply system; the voltage on which the power of a plant is delivered; a shortcircuit current for switchgear high voltage and the need for their limitation by circuit means; the most power that can be lost when damage to any switch. A model of reliability of the main circuit of electrical connections is designed to detect all types of accidents that are possible at the coincidence of failures of elements with the repair and operational modes that differs in composition and damageability of the equipment, as well as under conditions of the development of accidents due to failure of operation of devices of relay protection and automation.

  16. NASA Electric Propulsion System Studies

    Science.gov (United States)

    Felder, James L.

    2015-01-01

    An overview of NASA efforts in the area of hybrid electric and turboelectric propulsion in large transport. This overview includes a list of reasons why we are looking at transmitting some or all of the propulsive power for the aircraft electrically, a list of the different types of hybrid-turbo electric propulsion systems, and the results of 4 aircraft studies that examined different types of hybrid-turbo electric propulsion systems.

  17. RELIABILITY OF TRANSPORTATION SYSTEMS OF ROCK HAPS

    Directory of Open Access Journals (Sweden)

    A. Stepanov

    2009-01-01

    Full Text Available The ways of increasing of exploitation reliability of dump trucks with the aim of increasing of effectiveness of exploitation of transportation systems of rock heaps at coal mines.

  18. Reliability of microtechnology interconnects, devices and systems

    CERN Document Server

    Liu, Johan; Sarkka, Jussi; Tegehall, Per-Erik; Andersson, Cristina

    2011-01-01

    This text discusses the reliability of microtechnology products from the bottom up, beginning with devices and extending to systems. It covers many topics, and it addresses specific failure modes in solder and conductive adhesives at great length.

  19. Reliable Fluid Power Pitch Systems

    DEFF Research Database (Denmark)

    Liniger, Jesper; Pedersen, Henrik Clemmensen; Soltani, Mohsen

    2015-01-01

    The key objectives of wind turbine manufactures and buyers are to reduce the Total Cost of Ownership and Total Cost of Energy. Among others, low downtime of a wind turbine is important to increase the amount of energy produced during its lifetime. Historical data indicate that pitch systems accou...

  20. Design for Reliability in Renewable Energy Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Zhou, Dao; Sangwongwanich, Ariya

    2017-01-01

    Power electronics are widely used in renewable energy systems to achieve lower cost of energy, higher efficiency and high power density. At the same time, the high reliability of the power electronics products is demanded, in order to reduce the failure rates and ensure cost-effective operation...... of the renewable energy systems. This paper thus describes the basic concepts used in reliability engineering, and presents the status and future trends of Design for Reliability (DfR) in power electronics, which is currently undergoing a paradigm shift to a physics-of-failure approach. Two case studies of a 2 MW...

  1. Reliability and diagnostic of modular systems

    Directory of Open Access Journals (Sweden)

    J. Kohlas

    2014-01-01

    Full Text Available Reliability and diagnostic are in general two problems discussed separately. Yet the two problems are in fact closely related to each other. Here, this relation is considered in the simple case of modular systems. We show, how the computation of reliability and diagnostic can efficiently be done within the same Bayesian network induced by the modularity of the structure function of the system.

  2. 78 FR 7773 - Notice of Commissioner and Staff Attendance at North American Electric Reliability Corporation...

    Science.gov (United States)

    2013-02-04

    ... Board of Trustees Meetings, Board of Trustees Compliance Committee, Corporate Governance and Human Resources Committee, and Standards Oversight and Technology Committee Meetings. Hotel del Coronado, 1500... Association, Inc. v. Western Electric Coordinating Council and North American Electric Reliability Corporation...

  3. The Challenge Posed by Geomagnetic Activity to Electric Power Reliability: Evidence From England and Wales

    Science.gov (United States)

    Forbes, Kevin F.; St. Cyr, O. C.

    2017-10-01

    This paper addresses whether geomagnetic activity challenged the reliability of the electric power system during part of the declining phase of solar cycle 23. Operations by National Grid in England and Wales are examined over the period of 11 March 2003 through 31 March 2005. This paper examines the relationship between measures of geomagnetic activity and a metric of challenged electric power reliability known as the net imbalance volume (NIV). Measured in megawatt hours, NIV represents the sum of all energy deployments initiated by the system operator to balance the electric power system. The relationship between geomagnetic activity and NIV is assessed using a multivariate econometric model. The model was estimated using half-hour settlement data over the period of 11 March 2003 through 31 December 2004. The results indicate that geomagnetic activity had a demonstrable effect on NIV over the sample period. Based on the parameter estimates, out-of-sample predictions of NIV were generated for each half hour over the period of 1 January to 31 March 2005. Consistent with the existence of a causal relationship between geomagnetic activity and the electricity market imbalance, the root-mean-square error of the out-of-sample predictions of NIV is smaller; that is, the predictions are more accurate, when the statistically significant estimated effects of geomagnetic activity are included as drivers in the predictions.

  4. Electric power system / emergency power supply

    International Nuclear Information System (INIS)

    Dorn, P.G.

    1980-01-01

    One factor of reliability of reactor safety systems is the integrity of the power supply. The purpose of this paper is a review and a discussion of the safety objectives required for the planning, licensing, manufacture and erection of electrical power systems and components. The safety aspects and the technical background of the systems for - the electric auxiliary power supply system and - the emergency power supply system are outlined. These requirements result specially from the safety standards which are the framework for the studies of safety analysis. The overall and specific requirements for the electrical power supply of the safety systems are demonstrated on a 1300 MW standard nuclear power station with a pressurized water reactor. (orig.)

  5. Nodal price volatility reduction and reliability enhancement of restructured power systems considering demand-price elasticity

    International Nuclear Information System (INIS)

    Goel, L.; Wu, Qiuwei; Wang, Peng

    2008-01-01

    With the development of restructured power systems, the conventional 'same for all customers' electricity price is getting replaced by nodal prices. Electricity prices will fluctuate with time and nodes. In restructured power systems, electricity demands will interact mutually with prices. Customers may shift some of their electricity consumption from time slots of high electricity prices to those of low electricity prices if there is a commensurate price incentive. The demand side load shift will influence nodal prices in return. This interaction between demand and price can be depicted using demand-price elasticity. This paper proposes an evaluation technique incorporating the impact of the demand-price elasticity on nodal prices, system reliability and nodal reliabilities of restructured power systems. In this technique, demand and price correlations are represented using the demand-price elasticity matrix which consists of self/cross-elasticity coefficients. Nodal prices are determined using optimal power flow (OPF). The OPF and customer damage functions (CDFs) are combined in the proposed reliability evaluation technique to assess the reliability enhancement of restructured power systems considering demand-price elasticity. The IEEE reliability test system (RTS) is simulated to illustrate the developed techniques. The simulation results show that demand-price elasticity reduces the nodal price volatility and improves both the system reliability and nodal reliabilities of restructured power systems. Demand-price elasticity can therefore be utilized as a possible efficient tool to reduce price volatility and to enhance the reliability of restructured power systems. (author)

  6. Reliability demonstration of imaging surveillance systems

    International Nuclear Information System (INIS)

    Sheridan, T.F.; Henderson, J.T.; MacDiarmid, P.R.

    1979-01-01

    Security surveillance systems which employ closed circuit television are being deployed with increasing frequency for the protection of property and other valuable assets. A need exists to demonstrate the reliability of such systems before their installation to assure that the deployed systems will operate when needed with only the scheduled amount of maintenance and support costs. An approach to the reliability demonstration of imaging surveillance systems which employ closed circuit television is described. Failure definitions based on industry television standards and imaging alarm assessment criteria for surveillance systems are discussed. Test methods which allow 24 hour a day operation without the need for numerous test scenarios, test personnel and elaborate test facilities are presented. Existing reliability demonstration standards are shown to apply which obviate the need for elaborate statistical tests. The demonstration methods employed are shown to have applications in other types of imaging surveillance systems besides closed circuit television

  7. Natural-gas-powered thermoelectricity as a reliability factor in the Brazilian electric sector

    International Nuclear Information System (INIS)

    Fernandes, E.; Oliveira, J.C.S. de; de Oliveira, P.R.; Alonso, P.S.R.

    2008-01-01

    The introduction of natural-gas-powered thermoelectricity into the Brazilian generation sector can be considered as a very complex energy, economic, regulatory and institutional revision. Brazil is a country with very specific characteristics in electricity generation, as approximately 80% of the generating capacity is based on hydroelectricity, showing strong dependency on rain and management of water reservoirs. A low rate of investment in the Brazilian Electricity Industry in the period of 1995-2000, associated with periods of low rainfall, led to a dramatic lowering of the water stocks in the reservoirs. With this scenario and the growing supply of natural gas, both from within Brazil and imported, natural gas thermal electric plants became a good option to diversify the electrical supply system. In spite of the Brazilian Government's efforts to install such plants, the country was faced with severe electricity rationing in 2001. The objective of this work is to show the need to continue with the implementation of natural gas thermal electricity projects, in a manner that allows flexibility and guarantees greater working reliability for the entire Brazilian electricity sector. Taking into account the world trend towards renewable energy, the perspectives of usage of biofuels in the Brazilian Energy Matrix and in electrical energy generation are also analyzed. The very issue of electrical power efficiency in Brazil and its challenges and strategic proposals from the standpoint of Government Programs and results provided so far are presented. The technological constraints in order to put on stream the thermal electric plants are also analyzed. The article concludes with a positive perspective of the usage of natural gas as to be the third pillar in the Brazilian Energy Matrix for the years to come

  8. Reliability of operating WWER monitoring systems

    International Nuclear Information System (INIS)

    Yastrebenetsky, M.A.; Goldrin, V.M.; Garagulya, A.V.

    1996-01-01

    The elaboration of WWER monitoring systems reliability measures is described in this paper. The evaluation is based on the statistical data about failures what have collected at the Ukrainian operating nuclear power plants (NPP). The main attention is devoted to radiation safety monitoring system and unit information computer system, what collects information from different sensors and system of the unit. Reliability measures were used for decision the problems, connected with life extension of the instruments, and for other purposes. (author). 6 refs, 6 figs

  9. Reliability of operating WWER monitoring systems

    Energy Technology Data Exchange (ETDEWEB)

    Yastrebenetsky, M A; Goldrin, V M; Garagulya, A V [Ukrainian State Scientific Technical Center of Nuclear and Radiation Safety, Kharkov (Ukraine). Instrumentation and Control Systems Dept.

    1997-12-31

    The elaboration of WWER monitoring systems reliability measures is described in this paper. The evaluation is based on the statistical data about failures what have collected at the Ukrainian operating nuclear power plants (NPP). The main attention is devoted to radiation safety monitoring system and unit information computer system, what collects information from different sensors and system of the unit. Reliability measures were used for decision the problems, connected with life extension of the instruments, and for other purposes. (author). 6 refs, 6 figs.

  10. Distribution System Reliability Analysis for Smart Grid Applications

    Science.gov (United States)

    Aljohani, Tawfiq Masad

    Reliability of power systems is a key aspect in modern power system planning, design, and operation. The ascendance of the smart grid concept has provided high hopes of developing an intelligent network that is capable of being a self-healing grid, offering the ability to overcome the interruption problems that face the utility and cost it tens of millions in repair and loss. To address its reliability concerns, the power utilities and interested parties have spent extensive amount of time and effort to analyze and study the reliability of the generation and transmission sectors of the power grid. Only recently has attention shifted to be focused on improving the reliability of the distribution network, the connection joint between the power providers and the consumers where most of the electricity problems occur. In this work, we will examine the effect of the smart grid applications in improving the reliability of the power distribution networks. The test system used in conducting this thesis is the IEEE 34 node test feeder, released in 2003 by the Distribution System Analysis Subcommittee of the IEEE Power Engineering Society. The objective is to analyze the feeder for the optimal placement of the automatic switching devices and quantify their proper installation based on the performance of the distribution system. The measures will be the changes in the reliability system indices including SAIDI, SAIFI, and EUE. The goal is to design and simulate the effect of the installation of the Distributed Generators (DGs) on the utility's distribution system and measure the potential improvement of its reliability. The software used in this work is DISREL, which is intelligent power distribution software that is developed by General Reliability Co.

  11. Development in structural systems reliability theory

    International Nuclear Information System (INIS)

    Murotsu, Y.

    1986-01-01

    This paper is concerned with two topics on structural systems reliability theory. One covers automatic generation of failure mode equations, identifications of stochastically dominant failure modes, and reliability assessment of redundant structures. Reduced stiffness matrixes and equivalent nodal forces representing the failed elements are introduced for expressing the safety of the elements, using a matrix method. Dominant failure modes are systematically selected by a branch-and-bound technique and heuristic operations. The other discusses the various optimum design problems based on reliability concept. Those problems are interpreted through a solution to a multi-objective optimization problem. (orig.)

  12. Development in structural systems reliability theory

    Energy Technology Data Exchange (ETDEWEB)

    Murotsu, Y

    1986-07-01

    This paper is concerned with two topics on structural systems reliability theory. One covers automatic generation of failure mode equations, identifications of stochastically dominant failure modes, and reliability assessment of redundant structures. Reduced stiffness matrixes and equivalent nodal forces representing the failed elements are introduced for expressing the safety of the elements, using a matrix method. Dominant failure modes are systematically selected by a branch-and-bound technique and heuristic operations. The other discusses the various optimum design problems based on reliability concept. Those problems are interpreted through a solution to a multi-objective optimization problem.

  13. Reliability evaluation of a natural circulation system

    International Nuclear Information System (INIS)

    Jafari, Jalil; D'Auria, Francesco; Kazeminejad, Hossein; Davilu, Hadi

    2003-01-01

    This paper discusses a reliability study performed with reference to a passive thermohydraulic natural circulation (NC) system, named TTL-1. A methodology based on probabilistic techniques has been applied with the main purpose to optimize the system design. The obtained results have been adopted to estimate the thermal-hydraulic reliability (TH-R) of the same system. A total of 29 relevant parameters (including nominal values and plausible ranges of variations) affecting the design and the NC performance of the TTL-1 loop are identified and a probability of occurrence is assigned for each value based on expert judgment. Following procedures established for the uncertainty evaluation of thermal-hydraulic system codes results, 137 system configurations have been selected and each configuration has been analyzed via the Relap5 best-estimate code. The reference system configuration and the failure criteria derived from the 'mission' of the passive system are adopted for the evaluation of the system TH-R. Four different definitions of a less-than-unity 'reliability-values' (where unity represents the maximum achievable reliability) are proposed for the performance of the selected passive system. This is normally considered fully reliable, i.e. reliability-value equal one, in typical Probabilistic Safety Assessment (PSA) applications in nuclear reactor safety. The two 'point' TH-R values for the considered NC system were found equal to 0.70 and 0.85, i.e. values comparable with the reliability of a pump installed in an 'equivalent' forced circulation (active) system having the same 'mission'. The design optimization study was completed by a regression analysis addressing the output of the 137 calculations: heat losses, undetected leakage, loop length, riser diameter, and equivalent diameter of the test section have been found as the most important parameters bringing to the optimal system design and affecting the TH-R. As added values for this work, the comparison has

  14. System Reliability for LED-Based Products

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J Lynn; Mills, Karmann; Lamvik, Michael; Yaga, Robert; Shepherd, Sarah D; Bittle, James; Baldasaro, Nick; Solano, Eric; Bobashev, Georgiy; Johnson, Cortina; Evans, Amy

    2014-04-07

    Results from accelerated life tests (ALT) on mass-produced commercially available 6” downlights are reported along with results from commercial LEDs. The luminaires capture many of the design features found in modern luminaires. In general, a systems perspective is required to understand the reliability of these devices since LED failure is rare. In contrast, components such as drivers, lenses, and reflector are more likely to impact luminaire reliability than LEDs.

  15. Reliability testing of failed fuel location system

    International Nuclear Information System (INIS)

    Vieru, G.

    1996-01-01

    This paper presents the experimental reliability tests performed in order to prove the reliability parameters for Failed Fuel Location System (FFLS), equipment used to detect in which channel of a particular heat transport loop a fuel failure is located, and to find in which channel what particular bundle pair is failed. To do so, D20 samples from each reactor channel are sequentially monitored to detect a comparatively high level of delayed neutron activity. 15 refs, 8 figs, 2 tabs

  16. Transmission embedded cost allocation methodology with consideration of system reliability

    International Nuclear Information System (INIS)

    Hur, D.; Park, J.-K.; Yoo, C.-I.; Kim, B.H.

    2004-01-01

    In a vertically integrated utility industry, the cost of reliability, as a separate service, has not received much rigorous analysis. However, as a cornerstone of restructuring the industry, the transmission service pricing must change to be consistent with, and supportive of, competitive wholesale electricity markets. This paper focuses on the equitable allocation of transmission network embedded costs including the transmission reliability cost based on the contributions of each generator to branch flows under normal conditions as well as the line outage impact factor under a variety of load levels. A numerical example on a six-bus system is given to illustrate the applications of the proposed methodology. (author)

  17. Vehicle electrical system state controller

    Science.gov (United States)

    Bissontz, Jay E.

    2017-10-17

    A motor vehicle electrical power distribution system includes a plurality of distribution sub-systems, an electrical power storage sub-system and a plurality of switching devices for selective connection of elements of and loads on the power distribution system to the electrical power storage sub-system. A state transition initiator provides inputs to control system operation of switching devices to change the states of the power distribution system. The state transition initiator has a plurality of positions selection of which can initiate a state transition. The state transition initiator can emulate a four position rotary ignition switch. Fail safe power cutoff switches provide high voltage switching device protection.

  18. Software engineering practices for control system reliability

    International Nuclear Information System (INIS)

    S. K. Schaffner; K. S White

    1999-01-01

    This paper will discuss software engineering practices used to improve Control System reliability. The authors begin with a brief discussion of the Software Engineering Institute's Capability Maturity Model (CMM) which is a framework for evaluating and improving key practices used to enhance software development and maintenance capabilities. The software engineering processes developed and used by the Controls Group at the Thomas Jefferson National Accelerator Facility (Jefferson Lab), using the Experimental Physics and Industrial Control System (EPICS) for accelerator control, are described. Examples are given of how their procedures have been used to minimized control system downtime and improve reliability. While their examples are primarily drawn from their experience with EPICS, these practices are equally applicable to any control system. Specific issues addressed include resource allocation, developing reliable software lifecycle processes and risk management

  19. Heroic Reliability Improvement in Manned Space Systems

    Science.gov (United States)

    Jones, Harry W.

    2017-01-01

    System reliability can be significantly improved by a strong continued effort to identify and remove all the causes of actual failures. Newly designed systems often have unexpected high failure rates which can be reduced by successive design improvements until the final operational system has an acceptable failure rate. There are many causes of failures and many ways to remove them. New systems may have poor specifications, design errors, or mistaken operations concepts. Correcting unexpected problems as they occur can produce large early gains in reliability. Improved technology in materials, components, and design approaches can increase reliability. The reliability growth is achieved by repeatedly operating the system until it fails, identifying the failure cause, and fixing the problem. The failure rate reduction that can be obtained depends on the number and the failure rates of the correctable failures. Under the strong assumption that the failure causes can be removed, the decline in overall failure rate can be predicted. If a failure occurs at the rate of lambda per unit time, the expected time before the failure occurs and can be corrected is 1/lambda, the Mean Time Before Failure (MTBF). Finding and fixing a less frequent failure with the rate of lambda/2 per unit time requires twice as long, time of 1/(2 lambda). Cutting the failure rate in half requires doubling the test and redesign time and finding and eliminating the failure causes.Reducing the failure rate significantly requires a heroic reliability improvement effort.

  20. Reliability Prediction Approaches For Domestic Intelligent Electric Energy Meter Based on IEC62380

    Science.gov (United States)

    Li, Ning; Tong, Guanghua; Yang, Jincheng; Sun, Guodong; Han, Dongjun; Wang, Guixian

    2018-01-01

    The reliability of intelligent electric energy meter is a crucial issue considering its large calve application and safety of national intelligent grid. This paper developed a procedure of reliability prediction for domestic intelligent electric energy meter according to IEC62380, especially to identify the determination of model parameters combining domestic working conditions. A case study was provided to show the effectiveness and validation.

  1. Reliability constrained generation expansion planning with consideration of wind farms uncertainties in deregulated electricity market

    International Nuclear Information System (INIS)

    Hemmati, Reza; Hooshmand, Rahmat-Allah; Khodabakhshian, Amin

    2013-01-01

    Highlights: • Generation expansion planning is presented in deregulated electricity market. • Wind farm uncertainty is modeled in the problem. • The profit of each GENCO is maximized and also the safe operation of system is satisfied. • Salve sector is managed as an optimization programming and solved by using PSO technique. • Master sector is considered in pool market and Cournot model is used to simulate it. - Abstract: This paper addresses reliability constrained generation expansion planning (GEP) in the presence of wind farm uncertainty in deregulated electricity market. The proposed GEP aims at maximizing the expected profit of all generation companies (GENCOs), while considering security and reliability constraints such as reserve margin and loss of load expectation (LOLE). Wind farm uncertainty is also considered in the planning and GENCOs denote their planning in the presence of wind farm uncertainty. The uncertainty is modeled by probability distribution function (PDF) and Monte-Carlo simulation (MCS) is used to insert uncertainty into the problem. The proposed GEP is a constrained, nonlinear, mixed-integer optimization programming and solved by using particle swarm optimization (PSO) method. In this paper, Electricity market structure is modeled as a pool market. Simulation results verify the effectiveness and validity of the proposed planning for maximizing GENCOs profit in the presence of wind farms uncertainties in electricity market

  2. ARCHITECTURE AND RELIABILITY OF OPERATING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Stanislav V. Nazarov

    2018-03-01

    Full Text Available Progress in the production technology of microprocessors significantly increased reliability and performance of the computer systems hardware. It cannot be told about the corresponding characteristics of the software and its basis – the operating system (OS. Some achievements of program engineering are more modest in this field. Both directions of OS improvement (increasing of productivity and reliability are connected with the development of effective structures of these systems. OS functional complexity leads to the multiplicity of the structure, which is further enhanced by the specialization of the operating system depending on scope of computer system (complex scientific calculations, real time, information retrieval systems, systems of the automated and automatic control, etc. The functional complexity of the OS leads to the complexity of its architecture, which is further enhanced by the specialization of the operating system, depending on the computer system application area (complex scientific calculations, real-time, information retrieval systems, automated and automatic control systems, etc.. That fact led to variety of modern OS. It is possible to estimate reliability of different OS structures only as results of long-term field experiment or simulation modeling. However it is most often unacceptable because of time and funds expenses for carrying out such research. This survey attempts to evaluate the reliability of two main OS architectures: large multi-layered modular core and a multiserver (client-server system. Represented by continuous Markov chains which are explored in the stationary mode on the basis of transition from systems of the differential equations of Kolmogorov to system of the linear algebraic equations, models of these systems are developed.

  3. Reliability-Based Optimization of Series Systems of Parallel Systems

    DEFF Research Database (Denmark)

    Enevoldsen, I.; Sørensen, John Dalsgaard

    Reliability-based design of structural systems is considered. Especially systems where the reliability model is a series system of parallel systems are analysed. A sensitivity analysis for this class of problems is presented. Direct and sequential optimization procedures to solve the optimization...

  4. Drought and Heat Wave Impacts on Electricity Grid Reliability in Illinois

    Science.gov (United States)

    Stillwell, A. S.; Lubega, W. N.

    2016-12-01

    A large proportion of thermal power plants in the United States use cooling systems that discharge large volumes of heated water into rivers and cooling ponds. To minimize thermal pollution from these discharges, restrictions are placed on temperatures at the edge of defined mixing zones in the receiving waters. However, during extended hydrological droughts and heat waves, power plants are often granted thermal variances permitting them to exceed these temperature restrictions. These thermal variances are often deemed necessary for maintaining electricity reliability, particularly as heat waves cause increased electricity demand. Current practice, however, lacks tools for the development of grid-scale operational policies specifying generator output levels that ensure reliable electricity supply while minimizing thermal variances. Such policies must take into consideration characteristics of individual power plants, topology and characteristics of the electricity grid, and locations of power plants within the river basin. In this work, we develop a methodology for the development of these operational policies that captures necessary factors. We develop optimal rules for different hydrological and meteorological conditions, serving as rule curves for thermal power plants. The rules are conditioned on leading modes of the ambient hydrological and meteorological conditions at the different power plant locations, as the locations are geographically close and hydrologically connected. Heat dissipation in the rivers and cooling ponds is modeled using the equilibrium temperature concept. Optimal rules are determined through a Monte Carlo sampling optimization framework. The methodology is applied to a case study of eight power plants in Illinois that were granted thermal variances in the summer of 2012, with a representative electricity grid model used in place of the actual electricity grid.

  5. Reliability analysis in interdependent smart grid systems

    Science.gov (United States)

    Peng, Hao; Kan, Zhe; Zhao, Dandan; Han, Jianmin; Lu, Jianfeng; Hu, Zhaolong

    2018-06-01

    Complex network theory is a useful way to study many real complex systems. In this paper, a reliability analysis model based on complex network theory is introduced in interdependent smart grid systems. In this paper, we focus on understanding the structure of smart grid systems and studying the underlying network model, their interactions, and relationships and how cascading failures occur in the interdependent smart grid systems. We propose a practical model for interdependent smart grid systems using complex theory. Besides, based on percolation theory, we also study the effect of cascading failures effect and reveal detailed mathematical analysis of failure propagation in such systems. We analyze the reliability of our proposed model caused by random attacks or failures by calculating the size of giant functioning components in interdependent smart grid systems. Our simulation results also show that there exists a threshold for the proportion of faulty nodes, beyond which the smart grid systems collapse. Also we determine the critical values for different system parameters. In this way, the reliability analysis model based on complex network theory can be effectively utilized for anti-attack and protection purposes in interdependent smart grid systems.

  6. Design for Reliability of Power Electronics in Renewable Energy Systems

    DEFF Research Database (Denmark)

    Ma, Ke; Yang, Yongheng; Wang, Huai

    2014-01-01

    Power electronics is the enabling technology for maximizing the power captured from renewable electrical generation, e.g., the wind and solar technology, and also for an efficient integration into the grid. Therefore, it is important that the power electronics are reliable and do not have too many...... failures during operation which otherwise will increase cost for operation, maintenance and reputation. Typically, power electronics in renewable electrical generation has to be designed for 20–30 years of operation, and in order to do that, it is crucial to know about the mission profile of the power...... electronics technology as well as to know how the power electronics technology is loaded in terms of temperature and other stressors relevant, to reliability. Hence, this chapter will show the basics of power electronics technology for renewable energy systems, describe the mission profile of the technology...

  7. Extension planning for electrical energy supply systems

    International Nuclear Information System (INIS)

    Bieselt, R.

    1975-01-01

    In the future as well as in the past, and in particular in the next decade a considerable increase in electrical energy demand can be expected. To satisfy this demand in a reliable and sufficient manner will force the utilities to invest large sums of money for the operation and the extension of power generation and distribution plants. The size of these investments justifies the search for more and more comprehensive and at the same time more detailed planning methods. With the help of system analysis a planning model for the electricity supply industry of a major supply area will be designed. (orig./RW) [de

  8. Reliability analysis of reactor protection systems

    International Nuclear Information System (INIS)

    Alsan, S.

    1976-07-01

    A theoretical mathematical study of reliability is presented and the concepts subsequently defined applied to the study of nuclear reactor safety systems. The theory is applied to investigations of the operational reliability of the Siloe reactor from the point of view of rod drop. A statistical study conducted between 1964 and 1971 demonstrated that most rod drop incidents arose from circumstances associated with experimental equipment (new set-ups). The reliability of the most suitable safety system for some recently developed experimental equipment is discussed. Calculations indicate that if all experimental equipment were equipped with these new systems, only 1.75 rod drop accidents would be expected to occur per year on average. It is suggested that all experimental equipment should be equipped with these new safety systems and tested every 21 days. The reliability of the new safety system currently being studied for the Siloe reactor was also investigated. The following results were obtained: definite failures must be detected immediately as a result of the disturbances produced; the repair time must not exceed a few hours; the equipment must be tested every week. Under such conditions, the rate of accidental rod drops is about 0.013 on average per year. The level of nondefinite failures is less than 10 -6 per hour and the level of nonprotection 1 hour per year. (author)

  9. A reliability assessment methodology for the VHTR passive safety system

    International Nuclear Information System (INIS)

    Lee, Hyungsuk; Jae, Moosung

    2014-01-01

    The passive safety system of a VHTR (Very High Temperature Reactor), which has recently attracted worldwide attention, is currently being considered for the design of safety improvements for the next generation of nuclear power plants in Korea. The functionality of the passive system does not rely on an external source of an electrical support system, but on the intelligent use of natural phenomena. Its function involves an ultimate heat sink for a passive secondary auxiliary cooling system, especially during a station blackout such as the case of the Fukushima Daiichi reactor accidents. However, it is not easy to quantitatively evaluate the reliability of passive safety for the purpose of risk analysis, considering the existing active system failure since the classical reliability assessment method cannot be applied. Therefore, we present a new methodology to quantify the reliability based on reliability physics models. This evaluation framework is then applied to of the conceptually designed VHTR in Korea. The Response Surface Method (RSM) is also utilized for evaluating the uncertainty of the maximum temperature of nuclear fuel. The proposed method could contribute to evaluating accident sequence frequency and designing new innovative nuclear systems, such as the reactor cavity cooling system (RCCS) in VHTR to be designed and constructed in Korea.

  10. Potential of reversible solid oxide cells as electricity storage system

    OpenAIRE

    Di Giorgio, Paolo; Desideri, Umberto

    2016-01-01

    Electrical energy storage (EES) systems allow shifting the time of electric power generation from that of consumption, and they are expected to play a major role in future electric grids where the share of intermittent renewable energy systems (RES), and especially solar and wind power plants, is planned to increase. No commercially available technology complies with all the required specifications for an efficient and reliable EES system. Reversible solid oxide cells (ReSOC) working in both ...

  11. Sustainable, Reliable Mission-Systems Architecture

    Science.gov (United States)

    O'Neil, Graham; Orr, James K.; Watson, Steve

    2007-01-01

    A mission-systems architecture, based on a highly modular infrastructure utilizing: open-standards hardware and software interfaces as the enabling technology is essential for affordable and sustainable space exploration programs. This mission-systems architecture requires (a) robust communication between heterogeneous system, (b) high reliability, (c) minimal mission-to-mission reconfiguration, (d) affordable development, system integration, and verification of systems, and (e) minimal sustaining engineering. This paper proposes such an architecture. Lessons learned from the Space Shuttle program and Earthbound complex engineered system are applied to define the model. Technology projections reaching out 5 years are mde to refine model details.

  12. Power Processing Unit For Micro Satellite Electric Propulsion System

    Directory of Open Access Journals (Sweden)

    Savvas Spiridon

    2017-01-01

    Full Text Available The Micro Satellite Electric Propulsion System (MEPS program has been originated by the increasing need to provide a low-cost and low-power Electric Propulsion System (EPS for small satellites ( 92%, small size and weight and high reliability. Its functional modules and preliminary results obtained at breadboard level are also presented.

  13. Reliability analysis and assessment of structural systems

    International Nuclear Information System (INIS)

    Yao, J.T.P.; Anderson, C.A.

    1977-01-01

    The study of structural reliability deals with the probability of having satisfactory performance of the structure under consideration within any specific time period. To pursue this study, it is necessary to apply available knowledge and methodology in structural analysis (including dynamics) and design, behavior of materials and structures, experimental mechanics, and the theory of probability and statistics. In addition, various severe loading phenomena such as strong motion earthquakes and wind storms are important considerations. For three decades now, much work has been done on reliability analysis of structures, and during this past decade, certain so-called 'Level I' reliability-based design codes have been proposed and are in various stages of implementation. These contributions will be critically reviewed and summarized in this paper. Because of the undesirable consequences resulting from the failure of nuclear structures, it is important and desirable to consider the structural reliability in the analysis and design of these structures. Moreover, after these nuclear structures are constructed, it is desirable for engineers to be able to assess the structural reliability periodically as well as immediately following the occurrence of severe loading conditions such as a strong-motion earthquake. During this past decade, increasing use has been made of techniques of system identification in structural engineering. On the basis of non-destructive test results, various methods have been developed to obtain an adequate mathematical model (such as the equations of motion with more realistic parameters) to represent the structural system

  14. Can Slovakia secure reliable electricity supply without nuclear?

    International Nuclear Information System (INIS)

    Pnacek, I.

    2004-01-01

    In this presentation author deals with structure of electricity production in the Slovak republic in 2006 and perspectives of electricity supply up to 2020 year. Decommissioning of Unit 1 and Unit 2 of the Bohunice NPP and completion of Unit 3 and 4 of the Mochovce NPP are discussed

  15. System-Reliability Cumulative-Binomial Program

    Science.gov (United States)

    Scheuer, Ernest M.; Bowerman, Paul N.

    1989-01-01

    Cumulative-binomial computer program, NEWTONP, one of set of three programs, calculates cumulative binomial probability distributions for arbitrary inputs. NEWTONP, CUMBIN (NPO-17555), and CROSSER (NPO-17557), used independently of one another. Program finds probability required to yield given system reliability. Used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. Program written in C.

  16. A reliability design method for a lithium-ion battery pack considering the thermal disequilibrium in electric vehicles

    Science.gov (United States)

    Xia, Quan; Wang, Zili; Ren, Yi; Sun, Bo; Yang, Dezhen; Feng, Qiang

    2018-05-01

    With the rapid development of lithium-ion battery technology in the electric vehicle (EV) industry, the lifetime of the battery cell increases substantially; however, the reliability of the battery pack is still inadequate. Because of the complexity of the battery pack, a reliability design method for a lithium-ion battery pack considering the thermal disequilibrium is proposed in this paper based on cell redundancy. Based on this method, a three-dimensional electric-thermal-flow-coupled model, a stochastic degradation model of cells under field dynamic conditions and a multi-state system reliability model of a battery pack are established. The relationships between the multi-physics coupling model, the degradation model and the system reliability model are first constructed to analyze the reliability of the battery pack and followed by analysis examples with different redundancy strategies. By comparing the reliability of battery packs of different redundant cell numbers and configurations, several conclusions for the redundancy strategy are obtained. More notably, the reliability does not monotonically increase with the number of redundant cells for the thermal disequilibrium effects. In this work, the reliability of a 6 × 5 parallel-series configuration is the optimal system structure. In addition, the effect of the cell arrangement and cooling conditions are investigated.

  17. Reliability modeling of an engineered barrier system

    International Nuclear Information System (INIS)

    Ananda, M.M.A.; Singh, A.K.; Flueck, J.A.

    1993-01-01

    The Weibull distribution is widely used in reliability literature as a distribution of time to failure, as it allows for both increasing failure rate (IFR) and decreasing failure rate (DFR) models. It has also been used to develop models for an engineered barrier system (EBS), which is known to be one of the key components in a deep geological repository for high level radioactive waste (HLW). The EBS failure time can more realistically be modelled by an IFR distribution, since the failure rate for the EBS is not expected to decrease with time. In this paper, we use an IFR distribution to develop a reliability model for the EBS

  18. Reliability modeling of an engineered barrier system

    International Nuclear Information System (INIS)

    Ananda, M.M.A.; Singh, A.K.; Flueck, J.A.

    1993-01-01

    The Weibull distribution is widely used in reliability literature as a distribution of time to failure, as it allows for both increasing failure rate (IFR) and decreasing failure rate (DFR) models. It has also been used to develop models for an engineered barrier system (EBS), which is known to be one of the key components in a deep geological repository for high level radioactive waste (HLW). The EBS failure time can more realistically be modelled by an IFR distribution, since the failure rate for the EBS is not expected to decrease with time. In this paper, an IFR distribution is used to develop a reliability model for the EBS

  19. Making real-time reactive systems reliable

    Science.gov (United States)

    Marzullo, Keith; Wood, Mark

    1990-01-01

    A reactive system is characterized by a control program that interacts with an environment (or controlled program). The control program monitors the environment and reacts to significant events by sending commands to the environment. This structure is quite general. Not only are most embedded real time systems reactive systems, but so are monitoring and debugging systems and distributed application management systems. Since reactive systems are usually long running and may control physical equipment, fault tolerance is vital. The research tries to understand the principal issues of fault tolerance in real time reactive systems and to build tools that allow a programmer to design reliable, real time reactive systems. In order to make real time reactive systems reliable, several issues must be addressed: (1) How can a control program be built to tolerate failures of sensors and actuators. To achieve this, a methodology was developed for transforming a control program that references physical value into one that tolerates sensors that can fail and can return inaccurate values; (2) How can the real time reactive system be built to tolerate failures of the control program. Towards this goal, whether the techniques presented can be extended to real time reactive systems is investigated; and (3) How can the environment be specified in a way that is useful for writing a control program. Towards this goal, whether a system with real time constraints can be expressed as an equivalent system without such constraints is also investigated.

  20. Highly reliable electro-hydraulic control system

    International Nuclear Information System (INIS)

    Mande, Morima; Hiyama, Hiroshi; Takahashi, Makoto

    1984-01-01

    The unscheduled shutdown of nuclear power stations disturbs power system, and exerts large influence on power generation cost due to the lowering of capacity ratio; therefore, high reliability is required for the control system of nuclear power stations. Toshiba Corp. has exerted effort to improve the reliability of the control system of power stations, and in this report, the electro-hydraulic control system for the turbines of nuclear power stations is described. The main functions of the electro-hydraulic control system are the control of main steam pressure with steam regulation valves and turbine bypass valves, the control of turbine speed and load, the prevention of turbine overspeed, the protection of turbines and so on. The system is composed of pressure sensors and a speed sensor, the control board containing the electronic circuits for control computation and protective sequence, the oil cylinders, servo valves and opening detectors of the valves for control, a high pressure oil hydraulic machine and piping, the operating panel and so on. The main features are the adoption of tripling intermediate value selection method, the multiplying of protection sensors and the adoption of 2 out of 3 trip logic, the multiplying of power sources, the improvement of the reliability of electronic circuit hardware and oil hydraulic system. (Kako, I.)

  1. System Reliability for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Marquez-Dominguez, Sergio; Sørensen, John Dalsgaard

    2013-01-01

    E). In consequence, a rational treatment of uncertainties is done in order to assess the reliability of critical details in OWTs. Limit state equations are formulated for fatigue critical details which are not influenced by wake effects generated in offshore wind farms. Furthermore, typical bi-linear S-N curves...... are considered for reliability verification according to international design standards of OWTs. System effects become important for each substructure with many potential fatigue hot spots. Therefore, in this paper a framework for system effects is presented. This information can be e.g. no detection of cracks...... in inspections or measurements from condition monitoring systems. Finally, an example is established to illustrate the practical application of this framework for jacket type wind turbine substructure considering system effects....

  2. Electrical drives for direct drive renewable energy systems

    CERN Document Server

    Mueller, Markus

    2013-01-01

    Wind turbine gearboxes present major reliability issues, leading to great interest in the current development of gearless direct-drive wind energy systems. Offering high reliability, high efficiency and low maintenance, developments in these direct-drive systems point the way to the next generation of wind power, and Electrical drives for direct drive renewable energy systems is an authoritative guide to their design, development and operation. Part one outlines electrical drive technology, beginning with an overview of electrical generators for direct drive systems. Principles of electrical design for permanent magnet generators are discussed, followed by electrical, thermal and structural generator design and systems integration. A review of power electronic converter technology and power electronic converter systems for direct drive renewable energy applications is then conducted. Part two then focuses on wind and marine applications, beginning with a commercial overview of wind turbine drive systems and a...

  3. Electric Power Infrastructure Reliability and Security (EPIRS) Reseach and Development Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Rick Meeker; L. Baldwin; Steinar Dale; Alexander Domijan; Davild Larbalestier; Hui Li; Peter McLaren; Sastry Pamidi; Horatio Rodrigo; Michael Steurer

    2010-03-31

    Power systems have become increasingly complex and face unprecedented challenges posed by population growth, climate change, national security issues, foreign energy dependence and an aging power infrastructure. Increased demand combined with increased economic and environmental constraints is forcing state, regional and national power grids to expand supply without the large safety and stability margins in generation and transmission capacity that have been the rule in the past. Deregulation, distributed generation, natural and man-made catastrophes and other causes serve to further challenge and complicate management of the electric power grid. To meet the challenges of the 21st century while also maintaining system reliability, the electric power grid must effectively integrate new and advanced technologies both in the actual equipment for energy conversion, transfer and use, and in the command, control, and communication systems by which effective and efficient operation of the system is orchestrated - in essence, the 'smart grid'. This evolution calls for advances in development, integration, analysis, and deployment approaches that ultimately seek to take into account, every step of the way, the dynamic behavior of the system, capturing critical effects due to interdependencies and interaction. This approach is necessary to better mitigate the risk of blackouts and other disruptions and to improve the flexibility and capacity of the grid. Building on prior Navy and Department of Energy investments in infrastructure and resources for electric power systems research, testing, modeling, and simulation at the Florida State University (FSU) Center for Advanced Power Systems (CAPS), this project has continued an initiative aimed at assuring reliable and secure grid operation through a more complete understanding and characterization of some of the key technologies that will be important in a modern electric system, while also fulfilling an education and

  4. Reliability Standards of Complex Engineering Systems

    Science.gov (United States)

    Galperin, E. M.; Zayko, V. A.; Gorshkalev, P. A.

    2017-11-01

    Production and manufacture play an important role in today’s modern society. Industrial production is nowadays characterized by increased and complex communications between its parts. The problem of preventing accidents in a large industrial enterprise becomes especially relevant. In these circumstances, the reliability of enterprise functioning is of particular importance. Potential damage caused by an accident at such enterprise may lead to substantial material losses and, in some cases, can even cause a loss of human lives. That is why industrial enterprise functioning reliability is immensely important. In terms of their reliability, industrial facilities (objects) are divided into simple and complex. Simple objects are characterized by only two conditions: operable and non-operable. A complex object exists in more than two conditions. The main characteristic here is the stability of its operation. This paper develops the reliability indicator combining the set theory methodology and a state space method. Both are widely used to analyze dynamically developing probability processes. The research also introduces a set of reliability indicators for complex technical systems.

  5. Reliability and accuracy of Crystaleye spectrophotometric system.

    Science.gov (United States)

    Chen, Li; Tan, Jian Guo; Zhou, Jian Feng; Yang, Xu; Du, Yang; Wang, Fang Ping

    2010-01-01

    to develop an in vitro shade-measuring model to evaluate the reliability and accuracy of the Crystaleye spectrophotometric system, a newly developed spectrophotometer. four shade guides, VITA Classical, VITA 3D-Master, Chromascop and Vintage Halo NCC, were measured with the Crystaleye spectrophotometer in a standardised model, ten times for 107 shade tabs. The shade-matching results and the CIE L*a*b* values of the cervical, body and incisal regions for each measurement were automatically analysed using the supporting software. Reliability and accuracy were calculated for each shade tab both in percentage and in colour difference (ΔE). Difference was analysed by one-way ANOVA in the cervical, body and incisal regions. range of reliability was 88.81% to 98.97% and 0.13 to 0.24 ΔE units, and that of accuracy was 44.05% to 91.25% and 1.03 to 1.89 ΔE units. Significant differences in reliability and accuracy were found between the body region and the cervical and incisal regions. Comparisons made among regions and shade guides revealed that evaluation in ΔE was prone to disclose the differences. measurements with the Crystaleye spectrophotometer had similar, high reliability in different shade guides and regions, indicating predictable repeated measurements. Accuracy in the body region was high and less variable compared with the cervical and incisal regions.

  6. The electricity certificate system, 2007

    Energy Technology Data Exchange (ETDEWEB)

    2007-07-01

    The electricity certificate system is a market based support system to assist the expansion of electricity production in Sweden from renewable energy sources and peat. Its objective is to increase the production of electricity from such sources by 17 TWh by 2016 relative to the production level in 2002. It is part of the country's overall objective of moving Sweden towards a more ecologically sustainable energy system. This report describes the market status of the electricity certificate system, and includes statistics from 2003 to 2006. It is our aim to create a forum for continuously developing the statistical material and analyses, in order to assist those involved in the market, and all other interested persons, to follow achievement of the objectives set out in the Government's Bill No. 2005/06:154, Renewable Electricity with Green Certificates. It is also our aim that, in future, each issue of the report should include a more in depth theme article on some particular subject. This year the report provides expanded information and statistics on wind power. Electricity certificates are issued to those who produce electricity from various renewable energy sources, and from peat, and who have had their production plants approved by the Swedish Energy Agency. To date, certificates have been issued to producers of electricity from biofuels and peat, wind power, hydro power and solar energy. Production from the renewable sources amounted to 11.6 TWh in 2006, which is 5.1 TWh more than corresponding production in 2002

  7. Design for Reliability of Power Electronic Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Wang, Huai; Sangwongwanich, Ariya

    2018-01-01

    Power density, efficiency, cost, and reliability are the major challenges when designing a power electronic system. Latest advancements in power semiconductor devices (e.g., silicon carbide devices) and topological innovations have vital contributions to power density and efficiency. Nevertheless......, dedicated heat sink systems for thermal management are required to dissipate the power losses in power electronic systems; otherwise, the power devices will be heated up and eventually fail to operate. In addition, in many mission critical applications (e.g., marine systems), the operating condition (i...

  8. Reliability analysis of containment isolation systems

    International Nuclear Information System (INIS)

    Pelto, P.J.; Counts, C.A.

    1984-06-01

    The Pacific Northwest Laboratory (PNL) is reviewing available information on containment systems design, operating experience, and related research as part of a project being conducted by the Division of Systems Integration, US Nuclear Regulatory Commission. The basic objective of this work is to collect and consolidate data relevant to assessing the functional performance of containment isolation systems and to use this data to the extent possible to characterize containment isolation system reliability for selected reference designs. This paper summarizes the results from initial efforts which focused on collection of data from available documents and briefly describes detailed review and analysis efforts which commenced recently. 5 references

  9. Nuclear plant reliability data system. 1979 annual reports of cumulative system and component reliability

    International Nuclear Information System (INIS)

    1979-01-01

    The primary purposes of the information in these reports are the following: to provide operating statistics of safety-related systems within a unit which may be used to compare and evaluate reliability performance and to provide failure mode and failure rate statistics on components which may be used in failure mode effects analysis, fault hazard analysis, probabilistic reliability analysis, and so forth

  10. Modelling Reliability of Supply and Infrastructural Dependency in Energy Distribution Systems

    OpenAIRE

    Helseth, Arild

    2008-01-01

    This thesis presents methods and models for assessing reliability of supply and infrastructural dependency in energy distribution systems with multiple energy carriers. The three energy carriers of electric power, natural gas and district heating are considered. Models and methods for assessing reliability of supply in electric power systems are well documented, frequently applied in the industry and continuously being subject to research and improvement. On the contrary, there are compar...

  11. Coal-Powered Electric Generating Unit Efficiency and Reliability Dialogue: Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Emmanuel [Energetics, Inc., Columbia, MD (United States)

    2018-02-01

    Coal continues to play a critical role in powering the Nation’s electricity generation, especially for baseload power plants. With aging coal generation assets facing decreased performance due to the state of the equipment, and with challenges exacerbated by the current market pressures on the coal sector, there are opportunities to advance early-stage technologies that can retrofit or replace equipment components. These changes will eventually result in significant improvements in plant performance once further developed and deployed by industry. Research and development in areas such as materials, fluid dynamics, fuel properties and preparation characteristics, and a new generation of plant controls can lead to new components and systems that can help improve the efficiency and reliability of coal-fired power plants significantly, allowing these assets to continue to provide baseload power. Coal stockpiles at electricity generation plants are typically large enough to provide 30 to 60 days of power prior to resupply—significantly enhancing the stability and reliability of the U.S. electricity sector. Falling prices for non-dispatchable renewable energy and mounting environmental regulations, among other factors, have stimulated efforts to improve the efficiency of these coal-fired electric generating units (EGUs). In addition, increased reliance on natural gas and non-dispatchable energy sources has spurred efforts to further increase the reliability of coal EGUs. The Coal Powered EGU Efficiency and Reliability Dialogue brought together stakeholders from across the coal EGU industry to discuss methods for improvement. Participants at the event reviewed performance-enhancing innovations in coal EGUs, discussed the potential for data-driven management practices to increase efficiency and reliability, investigated the impacts of regulatory compliance on coal EGU performance, and discussed upcoming challenges for the coal industry. This report documents the key

  12. Reliable, Low Cost Distributed Generator/Utility System Interconnect: 2001 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    2003-08-01

    This report details a research program to develop requirements that support the definition, design, and demonstration of a distributed generation-electric power system interconnection interface concept that allows distributed generation to be interconnected to the electric power system in a manner that provides value to end users without compromising reliability and performance.

  13. States of Cybersecurity: Electricity Distribution System Discussions

    Energy Technology Data Exchange (ETDEWEB)

    Pena, Ivonne [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ingram, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Martin, Maurice [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-03-16

    State and local entities that oversee the reliable, affordable provision of electricity are faced with growing and evolving threats from cybersecurity risks to our nation's electricity distribution system. All-hazards system resilience is a shared responsibility among electric utilities and their regulators or policy-setting boards of directors. Cybersecurity presents new challenges and should be a focus for states, local governments, and Native American tribes that are developing energy-assurance plans to protect critical infrastructure. This research sought to investigate the implementation of governance and policy at the distribution utility level that facilitates cybersecurity preparedness to inform the U.S. Department of Energy (DOE), Office of Energy Policy and Systems Analysis; states; local governments; and other stakeholders on the challenges, gaps, and opportunities that may exist for future analysis. The need is urgent to identify the challenges and inconsistencies in how cybersecurity practices are being applied across the United States to inform the development of best practices, mitigations, and future research and development investments in securing the electricity infrastructure. By examining the current practices and applications of cybersecurity preparedness, this report seeks to identify the challenges and persistent gaps between policy and execution and reflect the underlying motivations of distinct utility structures as they play out at the local level. This study aims to create an initial baseline of cybersecurity preparedness within the distribution electricity sector. The focus of this study is on distribution utilities not bound by the cybersecurity guidelines of the North American Electric Reliability Corporation (NERC) to examine the range of mechanisms taken by state regulators, city councils that own municipal utilities, and boards of directors of rural cooperatives.

  14. Determination of the Level of Influence of Various Factors on the Reliability of Power System

    Directory of Open Access Journals (Sweden)

    Victor Popescu

    2014-09-01

    Full Text Available Consumers supply with qualitative electric power is one of the priority requirements imposed to power systems. Currently, in electricity networks take place a number of planned and unplanned disconnections, which interrupt the power and affect consumers, causing economic damage. To ensure the quality of power supply it is essential to know the factors that influence the reliability of power systems, which have a visible impact on the variation of reliability of equipment installed in power systems. This paper is devoted to problems of calculation and analysis of power systems reliability and estimation of the impact of various factors that influence the supply of consumers.

  15. Strategic defense and attack for reliability systems

    International Nuclear Information System (INIS)

    Hausken, Kjell

    2008-01-01

    This article illustrates a method by which arbitrarily complex series/parallel reliability systems can be analyzed. The method is illustrated with the series-parallel and parallel-series systems. Analytical expressions are determined for the investments and utilities of the defender and the attacker, depend on their unit costs of investment for each component, the contest intensity for each component, and their evaluations of the value of system functionality. For a series-parallel system, infinitely many components in parallel benefit the defender maximally regardless of the finite number of parallel subsystems in series. Conversely, infinitely many components in series benefit the attacker maximally regardless of the finite number of components in parallel in each subsystem. For a parallel-series system, the results are opposite. With equivalent components, equal unit costs for defender and attacker, equal intensity for all components, and equally many components in series and parallel, the defender always prefers the series-parallel system rather than the parallel-series system, and converse holds for the attacker. Hence from the defender's perspective, ceteris paribus, the series-parallel system is more reliable, and has fewer 'cut sets' or failure modes

  16. Electrical power system integrated thermal/electrical system simulation

    International Nuclear Information System (INIS)

    Freeman, W.E.

    1992-01-01

    This paper adds thermal properties to previously developed electrical Saber templates and incorporates these templates into a functional Electrical Power Subsystem (EPS) simulation. These combined electrical and thermal templates enable the complete and realistic simulation of a vehicle EPS on-orbit. Applications include on-orbit energy balance determinations for system load changes, initial array and battery EPS sizing for new EPS development, and array and battery technology trade studies. This effort proves the versatility of the Saber simulation program in handling varied and complex simulations accurately and in a reasonable amount of computer time. 9 refs

  17. Mass and Reliability System (MaRS)

    Science.gov (United States)

    Barnes, Sarah

    2016-01-01

    The Safety and Mission Assurance (S&MA) Directorate is responsible for mitigating risk, providing system safety, and lowering risk for space programs from ground to space. The S&MA is divided into 4 divisions: The Space Exploration Division (NC), the International Space Station Division (NE), the Safety & Test Operations Division (NS), and the Quality and Flight Equipment Division (NT). The interns, myself and Arun Aruljothi, will be working with the Risk & Reliability Analysis Branch under the NC Division's. The mission of this division is to identify, characterize, diminish, and communicate risk by implementing an efficient and effective assurance model. The team utilizes Reliability and Maintainability (R&M) and Probabilistic Risk Assessment (PRA) to ensure decisions concerning risks are informed, vehicles are safe and reliable, and program/project requirements are realistic and realized. This project pertains to the Orion mission, so it is geared toward a long duration Human Space Flight Program(s). For space missions, payload is a critical concept; balancing what hardware can be replaced by components verse by Orbital Replacement Units (ORU) or subassemblies is key. For this effort a database was created that combines mass and reliability data, called Mass and Reliability System or MaRS. The U.S. International Space Station (ISS) components are used as reference parts in the MaRS database. Using ISS components as a platform is beneficial because of the historical context and the environment similarities to a space flight mission. MaRS uses a combination of systems: International Space Station PART for failure data, Vehicle Master Database (VMDB) for ORU & components, Maintenance & Analysis Data Set (MADS) for operation hours and other pertinent data, & Hardware History Retrieval System (HHRS) for unit weights. MaRS is populated using a Visual Basic Application. Once populated, the excel spreadsheet is comprised of information on ISS components including

  18. A Novel Reliable WDM-PON System

    Science.gov (United States)

    Chen, Benyang; Gan, Chaoqin; Qi, Yongqian; Xia, Lei

    2011-12-01

    In this paper, a reliable Wavelength-Division-Multiplexing Passive Optical Network (WDM-PON) system is proposed. It can provide the protection against both the feeder fiber failure and the distribution fiber failure. When the fiber failure occurs, the corresponding switches in the OLT and in the ONU can switch to the protection link without affecting the users in normal status. That is to say, the protection for one ONU is independent of the other ONUs.

  19. 76 FR 42534 - Mandatory Reliability Standards for Interconnection Reliability Operating Limits; System...

    Science.gov (United States)

    2011-07-19

    ... Reliability Operating Limits; System Restoration Reliability Standards AGENCY: Federal Energy Regulatory... data necessary to analyze and monitor Interconnection Reliability Operating Limits (IROL) within its... Interconnection Reliability Operating Limits, Order No. 748, 134 FERC ] 61,213 (2011). \\2\\ The term ``Wide-Area...

  20. Systems reliability analysis: applications of the SPARCS System-Reliability Assessment Computer Program

    International Nuclear Information System (INIS)

    Locks, M.O.

    1978-01-01

    SPARCS-2 (Simulation Program for Assessing the Reliabilities of Complex Systems, Version 2) is a PL/1 computer program for assessing (establishing interval estimates for) the reliability and the MTBF of a large and complex s-coherent system of any modular configuration. The system can consist of a complex logical assembly of independently failing attribute (binomial-Bernoulli) and time-to-failure (Poisson-exponential) components, without regard to their placement. Alternatively, it can be a configuration of independently failing modules, where each module has either or both attribute and time-to-failure components. SPARCS-2 also has an improved super modularity feature. Modules with minimal-cut unreliabiliy calculations can be mixed with those having minimal-path reliability calculations. All output has been standardized to system reliability or probability of success, regardless of the form in which the input data is presented, and whatever the configuration of modules or elements within modules

  1. The electricity certificate system, 2008

    Energy Technology Data Exchange (ETDEWEB)

    2008-07-01

    The electricity certificate system is now in its sixth year. Since the start, both the system and the market have developed, and have undergone a number of changes. In January 2007, the Swedish Energy Agency published a report on the system, 'The electricity certificate system, 2006', to provide easily accessible information on the development of the system and to improve general understanding of it. With the passing of another year, it is now time for the third edition, 'The electricity certificate system, 2008', describing the market status of the electricity certificate system, with statistics from 2003 to 2007. This year's special theme chapter describes current support systems for renewable electricity production throughout the EU. The report also contains expanded information and statistics on biofuels, together with a new chapter that describes planned expansion of renewable electricity production up to 2012. The chapter on consumers' contribution to renewable electricity production has also been updated. A new feature this year is provided in the form of a number of tables at the end of the report, complementing the text. Through annual publication of the report, we hope to create a means of continuously developing the statistical material and analyses, in order to assist those involved in the market, and all other interested persons, to follow achievement of the objectives set out in the Government's Bill No. 205/06:154, 'Renewable electricity with green certificates'. We welcome views on the content and presentation of the report in order further to improve it. The target for the certificate system is to increase, by 2016, the annual production of electricity from renewable sources by 17 TWh relative to its production in 2002. So far, the actual production of renewable electricity is less than the indicative stage target for 2007. Nevertheless, progress is regarded as good, as there are many planned projects

  2. Reliability analysis for Atucha II reactor protection system signals

    International Nuclear Information System (INIS)

    Roca, Jose Luis

    1996-01-01

    Atucha II is a 745 MW Argentine Power Nuclear Reactor constructed by ENACE SA, Nuclear Argentine Company for Electrical Power Generation and SIEMENS AG KWU, Erlangen, Germany. A preliminary modular logic analysis of RPS (Reactor Protection System) signals was performed by means of the well known Swedish professional risk and reliability software named Risk-Spectrum taking as a basis a reference signal coded as JR17ER003 which command the two moderator loops valves. From the reliability and behavior knowledge for this reference signal follows an estimation of the reliability for the other 97 RPS signals. Because the preliminary character of this analysis Main Important Measures are not performed at this stage. Reliability is by the statistic value named unavailability predicted. The scope of this analysis is restricted from the measurement elements to the RPS buffer outputs. In the present context only one redundancy is analyzed so in the Instrumentation and Control area there no CCF (Common Cause Failures) present for signals. Finally those unavailability values could be introduced in the failure domain for the posterior complete Atucha II reliability analysis which includes all mechanical and electromechanical features. Also an estimation of the spurious frequency of RPS signals defined as faulty by no trip is performed

  3. Reliability analysis for Atucha II reactor protection system signals

    International Nuclear Information System (INIS)

    Roca, Jose L.

    2000-01-01

    Atucha II is a 745 MW Argentine power nuclear reactor constructed by Nuclear Argentine Company for Electric Power Generation S.A. (ENACE S.A.) and SIEMENS AG KWU, Erlangen, Germany. A preliminary modular logic analysis of RPS (Reactor Protection System) signals was performed by means of the well known Swedish professional risk and reliability software named Risk-Spectrum taking as a basis a reference signal coded as JR17ER003 which command the two moderator loops valves. From the reliability and behavior knowledge for this reference signal follows an estimation of the reliability for the other 97 RPS signals. Because the preliminary character of this analysis Main Important Measures are not performed at this stage. Reliability is by the statistic value named unavailability predicted. The scope of this analysis is restricted from the measurement elements to the RPS buffer outputs. In the present context only one redundancy is analyzed so in the Instrumentation and Control area there no CCF (Common Cause Failures) present for signals. Finally those unavailability values could be introduced in the failure domain for the posterior complete Atucha II reliability analysis which includes all mechanical and electromechanical features. Also an estimation of the spurious frequency of RPS signals defined as faulty by no trip is performed. (author)

  4. Proposed TFTR electrical system

    International Nuclear Information System (INIS)

    Bronner, G.; Murray, J.

    1975-01-01

    The development of controlled thermonuclear fusion has progressed to the stage where the present facilities and energy available for future devices are not sufficient and must be increased by about a factor of ten. This report describes the proposed TFTR ac utility power distribution system, an energy storage motor generator flywheel facility, and the rectifier conversion equipment for the Toroidal Field Confining System (TF), Ohmic Heating System (OH), Equilibrium Field System (EF) and the Neutral Beam Heating System (NB). The general requirements are described and the special design considerations identified

  5. Calculation of residual electricity mixes when accounting for the EECS (European Electricity Certificate System) - The need for a harmonised system

    International Nuclear Information System (INIS)

    Raadal, H. L.; Nyland, C. A.; Hanssen, O. J.

    2009-01-01

    According to the Electricity Directive, suppliers of electricity must disclose their electricity portfolio with regards to energy source and environmental impact. This paper gives some examples of disclosure systems and residual electricity mixes in Norway, Sweden and Finland, compared to an approach based on a common regional disclosure. Disclosures based on the E-TRACK standard are presented, as well as the variation in CO 2 emissions from different residual mixes. The results from this study clearly show that there is a need for a harmonised, transparent and reliable system for the accounting of electricity disclosure in Europe. (author)

  6. Electric vehicle data acquisition system

    DEFF Research Database (Denmark)

    Svendsen, Mathias; Winther-Jensen, Mads; Pedersen, Anders Bro

    2014-01-01

    and industrial applications, e.g. research in electric vehicle driving patterns, vehicle substitutability analysis and fleet management. The platform is based on a embedded computer running Linux, and features a high level of modularity and flexibility. The system operates independently of the make of the car......, by using the On-board Diagnostic port to identify car model and adapt its software accordingly. By utilizing on-board Global Navigation Satellite System, General Packet Radio Service, accelerometer, gyroscope and magnetometer, the system not only provides valuable data for research in the field of electric......A data acquisition system for electric vehicles is presented. The system connects to the On-board Diagnostic port of newer vehicles, and utilizes the in-vehicle sensor network, as well as auxiliary sensors, to gather data. Data is transmitted continuously to a central database for academic...

  7. System evaluations by means of reliability analyses

    International Nuclear Information System (INIS)

    Breiling, G.

    1976-01-01

    The objective of this study is to show which analysis requirements are associated with the claim that a reliability analysis, as practised at present, can provide a quantitative risk assessment in absolute terms. The question arises of whether this claim can be substantiated without direct access to the specialist technical departments of a manufacturer and to the multifarious detail information available in these departments. The individual problems arising in the course of such an analysis are discussed on the example of a reliability analysis of a core flooding system. The questions discussed relate to analysis organisation, sequence analysis, fault-tree analysis, and the treatment of operational processes superimposed on the failure and repair processes. (orig.) [de

  8. Reliability assessment of nuclear structural systems

    International Nuclear Information System (INIS)

    Reich, M.; Hwang, H.

    1983-01-01

    Reliability assessment of nuclear structural systems has been receiving more emphasis over the last few years. This paper deals with the recent progress made by the Structural Analysis Division of Brookhaven National Laboratory (BNL), in the development of a probability-based reliability analysis methodology for safety evaluation of reactor containments and other seismic category I structures. An important feature of this methodology is the incorporation of finite element analysis and random vibration theory. By utilizing this method, it is possible to evaluate the safety of nuclear structures under various static and dynamic loads in terms of limit state probability. Progress in other related areas, such as the establishment of probabilistic characteristics for various loads and structural resistance, are also described. Results of an application of the methodology to a realistic reinforced concrete containment subjected to dead and live loads, accidental internal pressures and earthquake ground accelerations are presented

  9. Development of Probabilistic Reliability Models of Photovoltaic System Topologies for System Adequacy Evaluation

    OpenAIRE

    Ahmad Alferidi; Rajesh Karki

    2017-01-01

    The contribution of solar power in electric power systems has been increasing rapidly due to its environmentally friendly nature. Photovoltaic (PV) systems contain solar cell panels, power electronic converters, high power switching and often transformers. These components collectively play an important role in shaping the reliability of PV systems. Moreover, the power output of PV systems is variable, so it cannot be controlled as easily as conventional generation due to the unpredictable na...

  10. Alternative electrical transmission systems and their environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.

    1977-08-01

    A general description is provided of electrical transmission systems as an aid in determining their environmental impacts. Alternating current, direct current, overhead systems, underground systems, and water crossings are treated. The cost, performance, reliability, safety, and environmental impact of these systems are compared.

  11. Equipment design for reliability testing of protection system

    International Nuclear Information System (INIS)

    Situmorang, Johnny; Tjahjono, H.; Santosa, A. Z.; Tjahjani, S.DT.; Ismu, P.H; Haryanto, D.; Mulyanto, D.; Kusmono, S

    1999-01-01

    The equipment for reliability testing of cable of protection system has been designed as a a furnace with the electric heater have a 4 kW power, and need time 10 minute to reach the designed maximum temperature 3000C. The dimension of furnace is 800 mm diameter and 2000 mm length is isolated use rockwool isolator and coated by aluminium. For the designed maximum temperature the surface temperature is 78 0c. Assemble of specimens is arranged horizontally in the furnace. The failure criteria will be defined based on the behaviour of the load circuit in each line of cable specimens

  12. Energy Management Systems to Reduce Electrical Energy Consumption

    OpenAIRE

    Oriti, Giovanna

    2015-01-01

    EXECUTIVE SUMMARY An energy management system comprises an electrical energy storage element such as a battery, renewable electrical energy sources such as solar and wind, a digital signal processing controller and a solid state power converter to interface the elements together. This hardware demonstration in the lab at the Naval Postgraduate School will focus on solid state power conversion methods to improve the reliability and efficiency of electrical energy consumption by Navy facilit...

  13. Reliability Analysis of Structural Timber Systems

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Hoffmeyer, P.

    2000-01-01

    Structural systems like timber trussed rafters and roof elements made of timber can be expected to have some degree of redundancy and nonlinear/plastic behaviour when the loading consists of for example snow or imposed load. In this paper this system effect is modelled and the statistic...... of variation. In the paper a stochastic model is described for the strength of a single piece of timber taking into account the stochastic variation of the strength and stiffness with length. Also stochastic models for different types of loads are formulated. First, simple representative systems with different...... types of redundancy and non-linearity are considered. The statistical characteristics of the load bearing capacity are determined by reliability analysis. Next, more complex systems are considered modelling the mechanical behaviour of timber roof elements I stressed skin panels made of timber. Using...

  14. Reliability of mobile systems in construction

    Science.gov (United States)

    Narezhnaya, Tamara; Prykina, Larisa

    2017-10-01

    The purpose of the article is to analyze the influence of the mobility of construction production in the article taking into account the properties of reliability and readiness. Basing on the studied systems the effectiveness and efficiency is estimated. The construction system is considered to be the complete organizational structure providing creation or updating of construction facilities. At the same time the production sphere of these systems joins the production on the building site itself, material and technical resources of the construction production and live labour in these spheres within the construction dynamics. The author concludes, that the estimation of the degree of mobility of systems the of construction production makes a great positive effect in the project.

  15. Optimization and Control of Electric Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lesieutre, Bernard C. [Univ. of Wisconsin, Madison, WI (United States); Molzahn, Daniel K. [Univ. of Wisconsin, Madison, WI (United States)

    2014-10-17

    The analysis and optimization needs for planning and operation of the electric power system are challenging due to the scale and the form of model representations. The connected network spans the continent and the mathematical models are inherently nonlinear. Traditionally, computational limits have necessitated the use of very simplified models for grid analysis, and this has resulted in either less secure operation, or less efficient operation, or both. The research conducted in this project advances techniques for power system optimization problems that will enhance reliable and efficient operation. The results of this work appear in numerous publications and address different application problems include optimal power flow (OPF), unit commitment, demand response, reliability margins, planning, transmission expansion, as well as general tools and algorithms.

  16. Apples to Apples: Equivalent-Reliability Power Systems Across Diverse Resource Mix Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Stephen, Gordon W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Frew, Bethany A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sigler, Devon [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jones, Wesley B [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-03-28

    Electricity market research is highly price sensitive, and prices are strongly influenced by balance of supply and demand. This work looks at how to combine capacity expansion models and reliability assessment tools to assess equivalent-reliability power systems across diverse resource mix scenarios.

  17. Reconstruction of electric systems (ELE)

    International Nuclear Information System (INIS)

    Kohutovic, P.

    2001-01-01

    The original design of WWER-230 units consisted of a single common system EEPS (essential electric power supply system) per unit. The establishment of redundancy 2 x 100% EEPS was a global task. The task was started during the 'Small reconstruction' - MR V1, continued in 'Gradual reconstruction' and finished in the year 2000. (author)

  18. The Brazilian electrical system reform

    International Nuclear Information System (INIS)

    Mendonca, A.F.; Dahl, C.

    1999-01-01

    Although the Brazilian electrical system has been a public monopoly, the threat of electricity shortages from a lack of investment triggered a comprehensive reform. In 1993 the government began a series of laws, decrees and regulations reforming the tariff policy, allowing privatization of utilities, foreign investments and independent power producers, and creating an independent transmission grid and a new electricity regulatory agency (ANEEL). The new regulatory framework is not completely defined but the proposed model intends to transform bulk electricity supply into a competitive market similar to that adopted in England. Our objective is to evaluate whether the proposed reform will succeed in attracting the required private capital, will allow an unregulated wholesale electricity market and will require a strict regulatory framework. The reform has been quite successful in privatizing the distribution companies but is allowing monopolistic rents, and has failed until now to attract private investments to expand generation capacity. The risk of blackouts has increased, and the proposed wholesale electricity market may not be appropriate because of barriers to constructing new hydroelectric units, now 90% of the system. Therefore, a new regulatory framework and a strong regulatory agency with a well-defined tariff policy should have preceded the privatization. (author)

  19. SLAC modulator system improvements and reliability results

    International Nuclear Information System (INIS)

    Donaldson, A.R.

    1998-06-01

    In 1995, an improvement project was completed on the 244 klystron modulators in the linear accelerator. The modulator system has been previously described. This article offers project details and their resulting effect on modulator and component reliability. Prior to the project, the authors had collected four operating cycles (1991 through 1995) of MTTF data. In this discussion, the '91 data will be excluded since the modulators operated at 60 Hz. The five periods following the '91 run were reviewed due to the common repetition rate at 120 Hz

  20. Extrapolation Method for System Reliability Assessment

    DEFF Research Database (Denmark)

    Qin, Jianjun; Nishijima, Kazuyoshi; Faber, Michael Havbro

    2012-01-01

    of integrals with scaled domains. The performance of this class of approximation depends on the approach applied for the scaling and the functional form utilized for the extrapolation. A scheme for this task is derived here taking basis in the theory of asymptotic solutions to multinormal probability integrals......The present paper presents a new scheme for probability integral solution for system reliability analysis, which takes basis in the approaches by Naess et al. (2009) and Bucher (2009). The idea is to evaluate the probability integral by extrapolation, based on a sequence of MC approximations...... that the proposed scheme is efficient and adds to generality for this class of approximations for probability integrals....

  1. Reliability of dynamic systems under limited information.

    Energy Technology Data Exchange (ETDEWEB)

    Field, Richard V., Jr. (.,; .); Grigoriu, Mircea

    2006-09-01

    A method is developed for reliability analysis of dynamic systems under limited information. The available information includes one or more samples of the system output; any known information on features of the output can be used if available. The method is based on the theory of non-Gaussian translation processes and is shown to be particularly suitable for problems of practical interest. For illustration, we apply the proposed method to a series of simple example problems and compare with results given by traditional statistical estimators in order to establish the accuracy of the method. It is demonstrated that the method delivers accurate results for the case of linear and nonlinear dynamic systems, and can be applied to analyze experimental data and/or mathematical model outputs. Two complex applications of direct interest to Sandia are also considered. First, we apply the proposed method to assess design reliability of a MEMS inertial switch. Second, we consider re-entry body (RB) component vibration response during normal re-entry, where the objective is to estimate the time-dependent probability of component failure. This last application is directly relevant to re-entry random vibration analysis at Sandia, and may provide insights on test-based and/or model-based qualification of weapon components for random vibration environments.

  2. Electrical power systems for Mars

    Science.gov (United States)

    Giudici, Robert J.

    1986-01-01

    Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

  3. System reliability analysis with natural language and expert's subjectivity

    International Nuclear Information System (INIS)

    Onisawa, T.

    1996-01-01

    This paper introduces natural language expressions and expert's subjectivity to system reliability analysis. To this end, this paper defines a subjective measure of reliability and presents the method of the system reliability analysis using the measure. The subjective measure of reliability corresponds to natural language expressions of reliability estimation, which is represented by a fuzzy set defined on [0,1]. The presented method deals with the dependence among subsystems and employs parametrized operations of subjective measures of reliability which can reflect expert 's subjectivity towards the analyzed system. The analysis results are also expressed by linguistic terms. Finally this paper gives an example of the system reliability analysis by the presented method

  4. Control system reliability at Jefferson Lab

    International Nuclear Information System (INIS)

    White, K.S.; Areti, H.; Garza, O.

    1997-01-01

    At Thomas Jefferson National Accelerator Facility (Jefferson Lab), the availability of the control system is crucial to the operation of the accelerator for experimental programs. Jefferson Lab's control system, uses 68040 based microprocessors running VxWorks, Unix workstations, and a variety of VME, CAMAC. GPIB, and serial devices. The software consists of control system toolkit software, commercial packages, and over 200 custom and generic applications, some of which are highly complex. The challenge is to keep this highly diverse and still growing system, with over 162,000 control points, operating reliably, while managing changes and upgrades to both the hardware and software. Downtime attributable to the control system includes the time to troubleshoot and repair problems and the time to restore the machine to operation of the scheduled program. This paper describes the availability of the control system during the last year, the heaviest contributors to downtime and the response to problems. Strategies for improving the robustness of the control system am detailed and include changes in hardware, software, procedures and processes. The improvements range from the routine preventive hardware maintenance, to improving their ability to detect, predict and prevent problems. This paper also describes the software tools used to assist in control system troubleshooting, maintenance and failure recovery processes

  5. Reliability worth assessment of radial systems with distributed generation

    OpenAIRE

    Bellart Llavall, Francesc Xavier

    2010-01-01

    With recent advances in technology, utilities generation (DG) on the distribution systems. Reliability worth is very important in power system planning and operation. Having a DG ensures reli increase the reliability worth. This research project presents the study of a radial distribution system and the impact of placing DG in order to increase the reliability worth. where a DG have to be placed. The reliability improvement is measured by different reliability indices tha...

  6. Reliability of copper based alloys for electric resistance spot welding

    International Nuclear Information System (INIS)

    Jovanovicj, M.; Mihajlovicj, A.; Sherbedzhija, B.

    1977-01-01

    Durability of copper based alloys (B-5 and B-6) for electric resistance spot-welding was examined. The total amount of Be, Ni and Zr was up to 2 and 1 wt.% respectively. Good durability and satisfactory quality of welded spots were obtained in previous laboratory experiments carried out on the fixed spot-welding machine of an industrial type (only B-5 alloy was examined). Electrodes made of both B-5 and B-6 alloy were tested on spot-welding grips and fixed spot-welding machines in Tvornica automobila Sarajevo (TAS). The obtained results suggest that the durability of electrodes made of B-5 and B-6 alloys is more than twice better than of that used in TAS

  7. Electrical power system WP-04

    Science.gov (United States)

    Nored, Donald L.

    1990-01-01

    Viewgraphs on Space Station Freedom Electrical Power System (EPS) WP-40 are presented. Topics covered include: key EPS technical requirements; photovoltaic power module systems; solar array assembly; blanket containment box and box positioning subassemblies; solar cell; bypass diode assembly; Kapton with atomic oxygen resistant coating; sequential shunt unit; gimbal assembly; energy storage subsystem; thermal control subsystem; direct current switching unit; integrated equipment assembly; PV cargo element; PMAD system; and PMC and AC architecture.

  8. System reliability time-dependent models

    International Nuclear Information System (INIS)

    Debernardo, H.D.

    1991-06-01

    A probabilistic methodology for safety system technical specification evaluation was developed. The method for Surveillance Test Interval (S.T.I.) evaluation basically means an optimization of S.T.I. of most important system's periodically tested components. For Allowed Outage Time (A.O.T.) calculations, the method uses system reliability time-dependent models (A computer code called FRANTIC III). A new approximation, which was called Independent Minimal Cut Sets (A.C.I.), to compute system unavailability was also developed. This approximation is better than Rare Event Approximation (A.E.R.) and the extra computing cost is neglectible. A.C.I. was joined to FRANTIC III to replace A.E.R. on future applications. The case study evaluations verified that this methodology provides a useful probabilistic assessment of surveillance test intervals and allowed outage times for many plant components. The studied system is a typical configuration of nuclear power plant safety systems (two of three logic). Because of the good results, these procedures will be used by the Argentine nuclear regulatory authorities in evaluation of technical specification of Atucha I and Embalse nuclear power plant safety systems. (Author) [es

  9. Enhanced Reliability of Photovoltaic Systems with Energy Storage and Controls

    Energy Technology Data Exchange (ETDEWEB)

    Manz, D.; Schelenz, O.; Chandra, R.; Bose, S.; de Rooij, M.; Bebic, J.

    2008-02-01

    This report summarizes efforts to reconfigure loads during outages to allow individual customers the opportunity to enhance the reliability of their electric service through the management of their loads, photovoltaics, and energy storage devices.

  10. Integrated Reliability and Risk Analysis System (IRRAS)

    International Nuclear Information System (INIS)

    Russell, K.D.; McKay, M.K.; Sattison, M.B.; Skinner, N.L.; Wood, S.T.; Rasmuson, D.M.

    1992-01-01

    The Integrated Reliability and Risk Analysis System (IRRAS) is a state-of-the-art, microcomputer-based probabilistic risk assessment (PRA) model development and analysis tool to address key nuclear plant safety issues. IRRAS is an integrated software tool that gives the user the ability to create and analyze fault trees and accident sequences using a microcomputer. This program provides functions that range from graphical fault tree construction to cut set generation and quantification. Version 1.0 of the IRRAS program was released in February of 1987. Since that time, many user comments and enhancements have been incorporated into the program providing a much more powerful and user-friendly system. This version has been designated IRRAS 4.0 and is the subject of this Reference Manual. Version 4.0 of IRRAS provides the same capabilities as Version 1.0 and adds a relational data base facility for managing the data, improved functionality, and improved algorithm performance

  11. Using VIIRS Day/Night Band to Measure Electricity Supply Reliability: Preliminary Results from Maharashtra, India

    Directory of Open Access Journals (Sweden)

    Michael L. Mann

    2016-08-01

    Full Text Available Unreliable electricity supplies are common in developing countries and impose large socio-economic costs, yet precise information on electricity reliability is typically unavailable. This paper presents preliminary results from a machine-learning approach for using satellite imagery of nighttime lights to develop estimates of electricity reliability for western India at a finer spatial scale. We use data from the Visible Infrared Imaging Radiometer Suite (VIIRS onboard the Suomi National Polar Partnership (SNPP satellite together with newly-available data from networked household voltage meters. Our results point to the possibilities of this approach as well as areas for refinement. With currently available training data, we find a limited ability to detect individual outages identified by household-level measurements of electricity voltage. This is likely due to the relatively small number of individual outages observed in our preliminary data. However, we find that the approach can estimate electricity reliability rates for individual locations fairly well, with the predicted versus actual regression yielding an R2 > 0.5. We also find that, despite the after midnight overpass time of the SNPP satellite, the reliability estimates derived are representative of daytime reliability.

  12. A high reliability oxygen deficiency monitoring system

    International Nuclear Information System (INIS)

    Parry, R.; Claborn, G.; Haas, A.; Landis, R.; Page, W.; Smith, J.

    1993-01-01

    The escalating use of cryogens at national laboratories in general and accelerators in particular, along with the increased emphasis placed on personnel safety, mandates the development and installation of oxygen monitoring systems to insure personnel safety in the event of a cryogenic leak. Numerous vendors offer oxygen deficiency monitoring systems but fail to provide important features and/or flexibility. This paper describes a unique oxygen monitoring system developed for the Magnet Test Laboratory (MTL) at the Superconducting Super Collider Laboratory (SSCL). Features include: high reliability, oxygen cell redundancy, sensor longevity, simple calibration, multiple trip points, offending sensor audio and visual indication, global alarms for building evacuation, local and remote analog readout, event and analog data logging, EMAIL event notification, phone line voice status system, and multi-drop communications network capability for reduced cable runs. Of particular importance is the distributed topology of the system which allows it to operate in a stand-alone configuration or to communicate with a host computer. This flexibility makes it ideal for small applications such as a small room containing a cryogenic dewar, as well as larger systems which monitor many offices and labs in several buildings

  13. A high reliability oxygen deficiency monitoring system

    International Nuclear Information System (INIS)

    Parry, R.; Claborn, G.; Haas, A.; Landis, R.; Page, W.; Smith, J.

    1993-05-01

    The escalating use of cryogens at national laboratories in general and accelerators in particular, along with the increased emphasis placed on personnel safety, mandates the development and installation of oxygen monitoring systems to insure personnel safety in the event of a cryogenic leak. Numerous vendors offer oxygen deficiency monitoring systems but fail to provide important features and/or flexibility. This paper describes a unique oxygen monitoring system developed for the Magnet Test Laboratory (MTL) at the Superconducting Super Collider Laboratory (SSCL). Features include: high reliability, oxygen cell redundancy, sensor longevity, simple calibration, multiple trip points, offending sensor audio and visual indication, global alarms for building evacuation, local and remote analog readout, event and analog data logging, EMAIL event notification, phone line voice status system, and multi-drop communications network capability for reduced cable runs. Of particular importance is the distributed topology of the system which allows it to operate in a stand-alone configuration or to communicate with a host computer. This flexibility makes it ideal for small applications such as a small room containing a cryogenic dewar, as well as larger systems which monitor many offices and labs in several buildings

  14. Probabilistic risk assessment course documentation. Volume 3. System reliability and analysis techniques, Session A - reliability

    International Nuclear Information System (INIS)

    Lofgren, E.V.

    1985-08-01

    This course in System Reliability and Analysis Techniques focuses on the quantitative estimation of reliability at the systems level. Various methods are reviewed, but the structure provided by the fault tree method is used as the basis for system reliability estimates. The principles of fault tree analysis are briefly reviewed. Contributors to system unreliability and unavailability are reviewed, models are given for quantitative evaluation, and the requirements for both generic and plant-specific data are discussed. Also covered are issues of quantifying component faults that relate to the systems context in which the components are embedded. All reliability terms are carefully defined. 44 figs., 22 tabs

  15. Reliability analysis of self-actuated shutdown system

    International Nuclear Information System (INIS)

    Itooka, S.; Kumasaka, K.; Okabe, A.; Satoh, K.; Tsukui, Y.

    1991-01-01

    An analytical study was performed for the reliability of a self-actuated shutdown system (SASS) under the unprotected loss of flow (ULOF) event in a typical loop-type liquid metal fast breeder reactor (LMFBR) by the use of the response surface Monte Carlo analysis method. Dominant parameters for the SASS, such as Curie point characteristics, subassembly outlet coolant temperature, electromagnetic surface condition, etc., were selected and their probability density functions (PDFs) were determined by the design study information and experimental data. To get the response surface function (RSF) for the maximum coolant temperature, transient analyses of ULOF were performed by utilizing the experimental design method in the determination of analytical cases. Then, the RSF was derived by the multi-variable regression analysis. The unreliability of the SASS was evaluated as a probability that the maximum coolant temperature exceeded an acceptable level, employing the Monte Carlo calculation using the above PDFs and RSF. In this study, sensitivities to the dominant parameter were compared. The dispersion of subassembly outlet coolant temperature near the SASS-was found to be one of the most sensitive parameters. Fault tree analysis was performed using this value for the SASS in order to evaluate the shutdown system reliability. As a result of this study, the effectiveness of the SASS on the reliability improvement in the LMFBR shutdown system was analytically confirmed. This study has been performed as a part of joint research and development projects for DFBR under the sponsorship of the nine Japanese electric power companies, Electric Power Development Company and the Japan Atomic Power Company. (author)

  16. Identifying factors influencing reliability of professional systems

    NARCIS (Netherlands)

    Balasubramanian, A.; Kevrekidis, K.; Sonnemans, P.J.M.; Newby, M.J.

    2008-01-01

    Modern product development strategies call for a more proactive approach to fight intense global competition in terms of technological innovation, shorter time to market, quality and reliability and accommodative price. From a reliability engineering perspective, development managers would like to

  17. Empowering Variable Renewables - Options for Flexible Electricity Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, Hugo [Renewable Energy Unit, International Energy Agency, Paris (France)

    2008-07-01

    A flexible electricity system is one that can respond reliably, and rapidly, to large fluctuations in supply and demand. Flexibility is already present in all power systems, in order to manage fluctuations in demand, and it is crucial for high performance and economic and reliable operation. This paper looks at measures to increase flexibility. but careful cost/benefit analysis is essential, and specific national and regional circumstances will influence the choice of option(s).

  18. Diagnostics and reliability of pipeline systems

    CERN Document Server

    Timashev, Sviatoslav

    2016-01-01

    The book contains solutions to fundamental problems which arise due to the logic of development of specific branches of science, which are related to pipeline safety, but mainly are subordinate to the needs of pipeline transportation.          The book deploys important but not yet solved aspects of reliability and safety assurance of pipeline systems, which are vital aspects not only for the oil and gas industry and, in general, fuel and energy industries , but also to virtually all contemporary industries and technologies. The volume will be useful to specialists and experts in the field of diagnostics/ inspection, monitoring, reliability and safety of critical infrastructures. First and foremost, it will be useful to the decision making persons —operators of different types of pipelines, pipeline diagnostics/inspection vendors, and designers of in-line –inspection (ILI) tools, industrial and ecological safety specialists, as well as to researchers and graduate students.

  19. Exploitation examination of reliability of coal dust systems

    International Nuclear Information System (INIS)

    Dojchinovski, Ilija; Trajkovski, Kole

    1997-01-01

    Designers and operators wish is, long, failure free operation at designed parameters of every system. Always we know the system start up time, but we don't know how long this system will operate successfully. Because of that in this article is given a method how, step by step, to determine the reliability of the system. Reliability parameters are obtained from experimental and operational data. When reliability parameters are determined then it is very easy to compare reliability of similar systems, for example excavators, or different systems, such as truck and rubber band transport system. Practical use of the theory of reliability is by purchasing of the systems when manufacturers have to have and present reliability parameters and on this way we can decide which system satisfies our needs regarding the quality-price-reliability. Reliability can be practically used in system operation where: 1) system reliability is maintained with proper start, use and shutdown of the system; 2) a system reliability is maintained with good maintenance organization; 3) a system reliability is maintained with innovations and improvements with final purpose removing of the imperfections experienced through the operation. Reliability is very important parameter in power generation plants. (Author)

  20. Electricity pricing and management systems

    International Nuclear Information System (INIS)

    Sawal, D.M.; Bajapai, Ashok

    1997-01-01

    The installed capacity of power generation in India is at present 80,000 MW. Out of the total 5.79 lakh inhabitated villages in the country, 4.79 villages have been electrified so far. Total number of consumers of electricity are about 95 million in the country. For such a large country with population of over 900 million and area of 32.873 lakh sq. kms., the role of electricity pricing and management system of the power sector is of paramount importance

  1. HEMP emergency planning and operating procedures for electric power systems

    Energy Technology Data Exchange (ETDEWEB)

    Reddoch, T.W.; Markel, L.C. (Electrotek Concepts, Inc., Knoxville, TN (United States))

    1991-01-01

    Investigations of the impact of high-altitude electromagnetic pulse (HEMP) on electric power systems and electrical equipment have revealed that HEMP creates both misoperation and failures. These events result from both the early time E[sub 1] (steep-front pulse) component and the late time E[sub 3] (geomagnetic perturbations) component of HEMP. In this report a HEMP event is viewed in terms of its marginal impact over classical power system disturbances by considering the unique properties and consequences of HEMP. This report focuses on system-wide electrical component failures and their potential consequences from HEMP. In particular, the effectiveness of planning and operating procedures for electric systems is evaluated while under the influence of HEMP. This assessment relies on published data and characterizes utilities using the North American Electric Reliability Council's regions and guidelines to model electric power system planning and operations. Key issues addressed by the report include how electric power systems are affected by HEMP and what actions electric utilities can initiate to reduce the consequences of HEMP. The report also reviews the salient features of earlier HEMP studies and projects, examines technology trends in the electric power industry which are affected by HEMP, characterizes the vulnerability of power systems to HEMP, and explores the capability of electric systems to recover from a HEMP event.

  2. Failure and Reliability Analysis for the Master Pump Shutdown System

    International Nuclear Information System (INIS)

    BEVINS, R.R.

    2000-01-01

    The Master Pump Shutdown System (MPSS) will be installed in the 200 Areas of the Hanford Site to monitor and control the transfer of liquid waste between tank farms and between the 200 West and 200 East areas through the Cross-Site Transfer Line. The Safety Function provided by the MPSS is to shutdown any waste transfer process within or between tank farms if a waste leak should occur along the selected transfer route. The MPSS, which provides this Safety Class Function, is composed of Programmable Logic Controllers (PLCs), interconnecting wires, relays, Human to Machine Interfaces (HMI), and software. These components are defined as providing a Safety Class Function and will be designated in this report as MPSS/PLC. Input signals to the MPSS/PLC are provided by leak detection systems from each of the tank farm leak detector locations along the waste transfer route. The combination of the MPSS/PLC, leak detection system, and transfer pump controller system will be referred to as MPSS/SYS. The components addressed in this analysis are associated with the MPSS/SYS. The purpose of this failure and reliability analysis is to address the following design issues of the Project Development Specification (PDS) for the MPSS/SYS (HNF 2000a): (1) Single Component Failure Criterion, (2) System Status Upon Loss of Electrical Power, (3) Physical Separation of Safety Class cables, (4) Physical Isolation of Safety Class Wiring from General Service Wiring, and (5) Meeting the MPSS/PLC Option 1b (RPP 1999) Reliability estimate. The failure and reliability analysis examined the system on a component level basis and identified any hardware or software elements that could fail and/or prevent the system from performing its intended safety function

  3. Pump system characterization and reliability enhancement

    International Nuclear Information System (INIS)

    Staunton, R.H.

    1998-01-01

    Pump characterization studies were performed at the Oak Ridge National Laboratory (ORNL) to review and analyze six years (1990-1995) of data from pump systems at domestic nuclear plants. The studies considered not only pumps and pump motors but also pump-related circuit breakers and turbine drives (i.e., the pump system). One significant finding was that the number of 'significant' failures of the pump circuit breaker exceeds the number of significant failures of the pump itself. The study also shows how regulatory code testing was designed for the pump only and therefore did not lead to the discovery of other significant pump system failures. Potential diagnostic technologies, both experimental and mature, suitable for on-line and off-line pump testing were identified. The study does not select or recommend technologies but proposes diagnostic technologies and monitoring techniques that should be further evaluated/developed for making meaningful and critically-needed improvements in the reliability of the pump system. (author)

  4. Reliability analysis of containment isolation systems

    International Nuclear Information System (INIS)

    Pelto, P.J.; Ames, K.R.; Gallucci, R.H.

    1985-06-01

    This report summarizes the results of the Reliability Analysis of Containment Isolation System Project. Work was performed in five basic areas: design review, operating experience review, related research review, generic analysis and plant specific analysis. Licensee Event Reports (LERs) and Integrated Leak Rate Test (ILRT) reports provided the major sources of containment performance information used in this study. Data extracted from LERs were assembled into a computer data base. Qualitative and quantitative information developed for containment performance under normal operating conditions and design basis accidents indicate that there is room for improvement. A rough estimate of overall containment unavailability for relatively small leaks which violate plant technical specifications is 0.3. An estimate of containment unavailability due to large leakage events is in the range of 0.001 to 0.01. These estimates are dependent on several assumptions (particularly on event duration times) which are documented in the report

  5. Reliability optimization using multiobjective ant colony system approaches

    International Nuclear Information System (INIS)

    Zhao Jianhua; Liu Zhaoheng; Dao, M.-T.

    2007-01-01

    The multiobjective ant colony system (ACS) meta-heuristic has been developed to provide solutions for the reliability optimization problem of series-parallel systems. This type of problems involves selection of components with multiple choices and redundancy levels that produce maximum benefits, and is subject to the cost and weight constraints at the system level. These are very common and realistic problems encountered in conceptual design of many engineering systems. It is becoming increasingly important to develop efficient solutions to these problems because many mechanical and electrical systems are becoming more complex, even as development schedules get shorter and reliability requirements become very stringent. The multiobjective ACS algorithm offers distinct advantages to these problems compared with alternative optimization methods, and can be applied to a more diverse problem domain with respect to the type or size of the problems. Through the combination of probabilistic search, multiobjective formulation of local moves and the dynamic penalty method, the multiobjective ACSRAP, allows us to obtain an optimal design solution very frequently and more quickly than with some other heuristic approaches. The proposed algorithm was successfully applied to an engineering design problem of gearbox with multiple stages

  6. Human reliability in complex systems: an overview

    International Nuclear Information System (INIS)

    Embrey, D.E.

    1976-07-01

    A detailed analysis is presented of the main conceptual background underlying the areas of human reliability and human error. The concept of error is examined and generalized to that of human reliability, and some of the practical and methodological difficulties of reconciling the different standpoints of the human factors specialist and the engineer discussed. Following a survey of general reviews available on human reliability, quantitative techniques for prediction of human reliability are considered. An in-depth critical analysis of the various quantitative methods is then presented, together with the data bank requirements for human reliability prediction. Reliability considerations in process control and nuclear plant, and also areas of design, maintenance, testing and emergency situations are discussed. The effects of stress on human reliability are analysed and methods of minimizing these effects discussed. Finally, a summary is presented and proposals for further research are set out. (author)

  7. Reliability of solid-state lighting electrical drivers subjected to WHTOL accelerated aging

    Energy Technology Data Exchange (ETDEWEB)

    Lall, Pradeep; Sakalauku, Peter; Davis, Lynn

    2014-05-27

    An investigation of a solid-state lighting (SSL) luminaire with the focus on the electronic driver which has been exposed to a standard wet hot temperature operating life (WHTOL) of 85% RH and 85°C in order to assess reliability of prolonged exposer to a harsh environment has been conducted. SSL luminaires are beginning introduced as head lamps in some of today's luxury automobiles and may also be fulfilling a variety of important outdoor applications such as overhead street lamps, traffic signals and landscape lighting. SSL luminaires in these environments are almost certain to encounter excessive moisture from humidity and high temperatures for a persistent period of time. The lack of accelerated test methods for LEDs to assess long-term reliability prior to introduction into the marketplace, a need for SSL physics based PHM modeling indicators for assessment and prediction of LED life, as well as the U.S. Department of Energy's R&D roadmap to replace todays lighting with SSL luminaires makes it important to increase the understanding of the reliability of SSL devices, specifically, in harsh environment applications. In this work, a set of SSL electrical drivers were investigated to determine failure mechanisms that occur during prolonged harsh environment applications. Each driver consists of four aluminum electrolytic capacitors (AECs) of three different types and was considered the weakest component inside the SSL electrical driver. The reliability of the electrical driver was assessed by monitoring the change in capacitance and the change in equivalent series resistance for each AEC, as well as monitoring the luminous flux of the SSL luminaire or the output of the electrical driver. The luminous flux of a pristine SSL electrical driver was also monitored in order to detect minute changes in the electrical drivers output and to aid in the investigation of the SSL luminaires reliability. The failure mechanisms of the electrical drivers have been

  8. Reliability Assessment of Offshore Wind Turbines Considering Faults of Electrical / Mechanical Components

    DEFF Research Database (Denmark)

    Kostandyan, Erik; Sørensen, John Dalsgaard

    2013-01-01

    For offshore wind turbines, the cost contribution to Cost of Energy from inspections and Operation & Maintenance can be substantial, and can be expected to increase when wind farms are placed at deeper water depths, further from the coast and in more harsh environments. Estimates of the reliability...... is considered and related to reliability estimation by taking into account faults e.g. due to failure of an electrical component or loss of grid....

  9. MYRRHA cryogenic system study on performances and reliability requirements

    International Nuclear Information System (INIS)

    Junquera, T.; Chevalier, N.R.; Thermeau, J.P.; Medeiros Romao, L.; Vandeplassche, D.

    2015-01-01

    A precise evaluation of the cryogenic requirements for accelerator-driven system such as the MYRRHA project has been performed. In particular, operation temperature, thermal losses, and required cryogenic power have been evaluated. A preliminary architecture of the cryogenic system including all its major components, as well as the principles for the cryogenic fluids distribution has been proposed. A detailed study on the reliability aspects has also been initiated. This study is based on the reliability of large cryogenic systems used for accelerators like HERA, LHC or SNS Linac. The requirements to guarantee good cryogenic system availability can be summarised as follows: 1) Mean Time Between Maintenance (MTBM) should be > 8 000 hours; 2) Valves, heat exchangers and turbines are particularly sensitive elements to impurities (dust, oil, gases), improvements are necessary to keep a minimal level in these components; 3) Redundancy studies for all elements containing moving/vibrating parts (turbines, compressors, including their respective bearings and seal shafts) are necessary; 4) Periodic maintenance is mandatory: oil checks, control of screw compressors every 10.000-15.000 hours, vibration surveillance programme, etc; 5) Special control and maintenance of utilities equipment (supply of cooling water, compressed air and electrical supply) is necessary; 6) Periodic vacuum checks to identify leakage appearance such as insulation vacuum of transfer lines and distribution boxes are necessary; 7) Easily exchangeable cold compressors are required

  10. Puget Sound Area Electric Reliability Plan : Appendix E, Transmission Reinforcement Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1992-04-01

    The purpose of this appendix to the draft environmental impact statement (EIS) report is to provide an update of the latest study work done on transmission system options for the Puget Sound Area Electric Reliability Plan. Also included in the attachments to the EIS are 2 reports analyzing the voltage stability of the Puget Sound transmission system and a review by Power Technologies, Inc. of the BPA voltage stability analysis and reactive options. Five transmission line options and several reactive options are presently being considered as possible solutions to the PSAFRP by the Transmission Team. The first two line options would be built on new rights-of way adjacent (as much as possible) to existing corridors. The reactive options would optimize the existing transmission system capability by adding new stations for series capacitors and/or switchgear. The other three line options are rebuilds or upgrades of existing cross mountain transmission lines. These options are listed below and include a preliminary assessment of the additional transmission system reinforcement required to integrate the new facilities into the existing transmission system. Plans were designed to provide at least 500 MVAR reactive margin.

  11. ac propulsion system for an electric vehicle

    Science.gov (United States)

    Geppert, S.

    1980-01-01

    It is pointed out that dc drives will be the logical choice for current production electric vehicles (EV). However, by the mid-80's, there is a good chance that the price and reliability of suitable high-power semiconductors will allow for a competitive ac system. The driving force behind the ac approach is the induction motor, which has specific advantages relative to a dc shunt or series traction motor. These advantages would be an important factor in the case of a vehicle for which low maintenance characteristics are of primary importance. A description of an EV ac propulsion system is provided, taking into account the logic controller, the inverter, the motor, and a two-speed transmission-differential-axle assembly. The main barrier to the employment of the considered propulsion system in EV is not any technical problem, but inverter transistor cost.

  12. Analysis of performance reliability of electrical and electronic equipment of car-tractor

    Directory of Open Access Journals (Sweden)

    Kravchenko О.Р.

    2016-08-01

    Full Text Available The analysis of the operational reliability of electrical and electronic equipment of vehicles, trucks Mercedes-Benz Actros 1844 LS and Volvo FH 1242, conducting international cargo transportation is performed. It is established that the equipment is reliable, which meets modern requirements, but where there is a violation of the resolution. The reason for repair work is constructive and operational factors. Distribution of efficiency and overall performance of operational reliability is retrieved. Items with more bounce are found. Common factors of violation of efficiency cars, trucks in operation, are largely different stages in warranty runs are obtained.

  13. Reliability engineering for nuclear and other high technology systems

    International Nuclear Information System (INIS)

    Lakner, A.A.; Anderson, R.T.

    1985-01-01

    This book is written for the reliability instructor, program manager, system engineer, design engineer, reliability engineer, nuclear regulator, probability risk assessment (PRA) analyst, general manager and others who are involved in system hardware acquisition, design and operation and are concerned with plant safety and operational cost-effectiveness. It provides criteria, guidelines and comprehensive engineering data affecting reliability; it covers the key aspects of system reliability as it relates to conceptual planning, cost tradeoff decisions, specification, contractor selection, design, test and plant acceptance and operation. It treats reliability as an integrated methodology, explicitly describing life cycle management techniques as well as the basic elements of a total hardware development program, including: reliability parameters and design improvement attributes, reliability testing, reliability engineering and control. It describes how these elements can be defined during procurement, and implemented during design and development to yield reliable equipment. (author)

  14. Alberta's new competitive electricity system

    International Nuclear Information System (INIS)

    Hancher, L.

    1996-01-01

    The shape, speed and direction of further reforms in Alberta's electric power industry were forecast, following the introduction of a competitive framework for the industry, the first province to do so in Canada, effective January 1996. This study reviews the previously existing system ( a mix of investor-owned and municipally-owned utilities), as well as the proposed new structure as laid out in the new Electric Utilities Act, based on the three principles of unbundling, a competitive power pool and open system access transmission. The paper also reviewed some of the major issues that will have to be faced in the future, such as how to deal with market power and possible collusion between the generators to hold prices down, a problem that has been the well-known failing of the U.K. pool mechanism

  15. Composite system reliability evaluation by stochastic calculation of system operation

    Energy Technology Data Exchange (ETDEWEB)

    Haubrick, H -J; Hinz, H -J; Landeck, E [Dept. of Power Systems and Power Economics (Germany)

    1994-12-31

    This report describes a new developed probabilistic approach for steady-state composite system reliability evaluation and its exemplary application to a bulk power test system. The new computer program called PHOENIX takes into consideration transmission limitations, outages of lines and power stations and, as a central element, a highly sophisticated model to the dispatcher performing remedial actions after disturbances. The kernel of the new method is a procedure for optimal power flow calculation that has been specially adapted for the use in reliability evaluations under the above mentioned conditions. (author) 11 refs., 8 figs., 1 tab.

  16. Manned spacecraft electrical power systems

    Science.gov (United States)

    Simon, William E.; Nored, Donald L.

    1987-01-01

    A brief history of the development of electrical power systems from the earliest manned space flights illustrates a natural trend toward a growth of electrical power requirements and operational lifetimes with each succeeding space program. A review of the design philosophy and development experience associated with the Space Shuttle Orbiter electrical power system is presented, beginning with the state of technology at the conclusion of the Apollo Program. A discussion of prototype, verification, and qualification hardware is included, and several design improvements following the first Orbiter flight are described. The problems encountered, the scientific and engineering approaches used to meet the technological challenges, and the results obtained are stressed. Major technology barriers and their solutions are discussed, and a brief Orbiter flight experience summary of early Space Shuttle missions is included. A description of projected Space Station power requirements and candidate system concepts which could satisfy these anticipated needs is presented. Significant challenges different from Space Shuttle, innovative concepts and ideas, and station growth considerations are discussed. The Phase B Advanced Development hardware program is summarized and a status of Phase B preliminary tradeoff studies is presented.

  17. IEEE guide for general principles of reliability analysis of nuclear power generating station protection systems

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Presented is the Institute of Electrical and Electronics Engineers, Inc. (IEEE) guide for general principles of reliability analysis of nuclear power generating station protection systems. The document has been prepared to provide the basic principles needed to conduct a reliability analysis of protection systems. Included is information on qualitative and quantitative analysis, guides for failure data acquisition and use, and guide for establishment of intervals

  18. 78 FR 44475 - Protection System Maintenance Reliability Standard

    Science.gov (United States)

    2013-07-24

    ... that the performance or product has some reliability-related value, then the requirement will have...] Protection System Maintenance Reliability Standard AGENCY: Federal Energy Regulatory Commission, Energy... Commission proposes to approve a revised Reliability Standard, PRC-005- 2--Protection System Maintenance, to...

  19. The development of the Czech Republic electric industry - Reliable, safe and responsible source mix

    Energy Technology Data Exchange (ETDEWEB)

    Vrba, Miroslav; Jez, Jiri; Ptacek, Jiri

    2010-09-15

    The paper focuses on the development of the Czech Republic electric industry in close perspective and the prediction of its expected future in period up to 2030. The goal of the paper is to specify methods and procedures applied within periodic assessment of Czech electric power sector balance outlook for the State authorities. A necessity to respect economic recession and politicization of the issue of power sector development has invoked that these items are added to commonly used procedures. A key criterion is the reliable and safe electricity supply by adequate source mix for acceptable prices and environmental aspects.

  20. Information and management system for the secondary electricity distribution network

    Energy Technology Data Exchange (ETDEWEB)

    Knezevic, M. (Rudnik i Termoelectrana Gacko u Osnivanju (Yugoslavia))

    1988-07-01

    Emphasizes the importance of a reliable and continuous secondary electrical distribution network for surface coal mine productivity. Interruptions in equipment operation caused by mechanical and electrical failures should be eliminated without delay. Effective communication systems should lead to reliable management and high productivity in mines. It is suggested that mines be divided into four groups according to their sensitivity to supply interruptions, and provided with remotely controlled signalling devices linked to main and auxiliary dispatching stations equipped with micro-computers. Productivity may be increased by some 50-70% and supply costs decreased by some 35% if appropriate electrical distribution systems are used. A sketch of a secondary electrical supply network is attached. 11 refs.

  1. Electric vehicle energy management system

    Science.gov (United States)

    Alaoui, Chakib

    This thesis investigates and analyzes novel strategies for the optimum energy management of electric vehicles (EVs). These are aimed to maximize the useful life of the EV batteries and make the EV more practical in order to increase its acceptability to market. The first strategy concerns the right choice of the batteries for the EV according to the user's driving habits, which may vary. Tests conducted at the University of Massachusetts Lowell battery lab show that the batteries perform differently from one manufacturer to the other. The second strategy was to investigate the fast chargeability of different batteries, which leads to reduce the time needed to recharge the EV battery pack. Tests were conducted again to prove that only few battery types could be fast charged. Test data were used to design a fast battery charger that could be installed in an EV charging station. The third strategy was the design, fabrication and application of an Electric Vehicle Diagnostic and Rejuvenation System (EVDRS). This system is based on Mosfet Controlled Thyristors (MCTs). It is capable of quickly identifying any failing battery(s) within the EV pack and rejuvenating the whole battery pack without dismantling them and unloading them. A novel algorithm to rejuvenate Electric Vehicle Sealed Lead Acid Batteries is described. This rejuvenation extends the useful life of the batteries and makes the EV more competitive. The fourth strategy was to design a thermal management system for EV, which is crucial to the safe operation, and the achievement of normal/optimal performance of, electric vehicle (EV) batteries. A novel approach for EV thermal management, based on Pettier-Effect heat pumps, was designed, fabricated and tested in EV. It shows the application of this type of technology for thermal management of EVs.

  2. Reliability

    OpenAIRE

    Condon, David; Revelle, William

    2017-01-01

    Separating the signal in a test from the irrelevant noise is a challenge for all measurement. Low test reliability limits test validity, attenuates important relationships, and can lead to regression artifacts. Multiple approaches to the assessment and improvement of reliability are discussed. The advantages and disadvantages of several different approaches to reliability are considered. Practical advice on how to assess reliability using open source software is provided.

  3. Maintenance Optimization Schedulingof Electric Power SystemsConsidering Renewable EnergySources

    OpenAIRE

    Yu, Jia

    2015-01-01

    Maintenance is crucial in any industry to keep components in a reasonable functionalcondition, especially in electric power system, where maintenance is done so that thefrequency and the duration of a fault can be shortened, thus increasing the availability of acertain component. And the reliability of the whole electric power system can also beimproved. In the many deregulated electricity markets, reliability and economic drivingforces are the two aspects that system operators mainly conside...

  4. Development of Probabilistic Reliability Models of Photovoltaic System Topologies for System Adequacy Evaluation

    Directory of Open Access Journals (Sweden)

    Ahmad Alferidi

    2017-02-01

    Full Text Available The contribution of solar power in electric power systems has been increasing rapidly due to its environmentally friendly nature. Photovoltaic (PV systems contain solar cell panels, power electronic converters, high power switching and often transformers. These components collectively play an important role in shaping the reliability of PV systems. Moreover, the power output of PV systems is variable, so it cannot be controlled as easily as conventional generation due to the unpredictable nature of weather conditions. Therefore, solar power has a different influence on generating system reliability compared to conventional power sources. Recently, different PV system designs have been constructed to maximize the output power of PV systems. These different designs are commonly adopted based on the scale of a PV system. Large-scale grid-connected PV systems are generally connected in a centralized or a string structure. Central and string PV schemes are different in terms of connecting the inverter to PV arrays. Micro-inverter systems are recognized as a third PV system topology. It is therefore important to evaluate the reliability contribution of PV systems under these topologies. This work utilizes a probabilistic technique to develop a power output model for a PV generation system. A reliability model is then developed for a PV integrated power system in order to assess the reliability and energy contribution of the solar system to meet overall system demand. The developed model is applied to a small isolated power unit to evaluate system adequacy and capacity level of a PV system considering the three topologies.

  5. 77 FR 59745 - Delegation of Authority Regarding Electric Reliability Organization's Budget, Delegation...

    Science.gov (United States)

    2012-10-01

    ...; Order No. 766] Delegation of Authority Regarding Electric Reliability Organization's Budget, Delegation... rule. SUMMARY: The Commission is issuing this Final Rule to revise its delegations of authority to... delegation agreements, and ERO policies and procedures. DATES: This rule is effective October 1, 2012. FOR...

  6. 78 FR 26349 - Notice of Commissioner and Staff Attendance at North American Electric Reliability Corporation...

    Science.gov (United States)

    2013-05-06

    ... Standards Oversight and Technology Committee Meetings Sheraton Boston Hotel, 39 Dalton Street, Boston, MA, 02199. May 8 (7:00 a.m.-5:00 p.m.) and May 9 (8:00 a.m.-1:00 p.m.), 2013 Further information regarding... American Electric Reliability Corporation For further information, please contact Jonathan First, 202-502...

  7. CADRIGS--computer aided design reliability interactive graphics system

    International Nuclear Information System (INIS)

    Kwik, R.J.; Polizzi, L.M.; Sticco, S.; Gerrard, P.B.; Yeater, M.L.; Hockenbury, R.W.; Phillips, M.A.

    1982-01-01

    An integrated reliability analysis program combining graphic representation of fault trees, automated data base loadings and reference, and automated construction of reliability code input files was developed. The functional specifications for CADRIGS, the computer aided design reliability interactive graphics system, are presented. Previously developed fault tree segments used in auxiliary feedwater system safety analysis were constructed on CADRIGS and, when combined, yielded results identical to those resulting from manual input to the same reliability codes

  8. Electricity system performance in Brazil

    International Nuclear Information System (INIS)

    Pires Rodrigues, A.; Souza Dias, D. De

    1992-01-01

    Nowadays, there is great uncertainty and concern about the capacity of the electric sector to go ahead with the programme of investments which was planned to keep pace with the growth in electricity demand. The sector is in an important financial crisis caused by the progressive reduction in its ability to generate resources either through self-financing or through external sources. The Brazilian electric sector is mostly public. Moreover, it is marked by a high degree of integration, which makes the whole system vulnerable to problem in each of its parts. First, the financial health of the Electrobras system which is at the top of the pyramidal sectoral structure depends on the capacity of the state-level utilities (operating mainly on the distribution side) to pay for the bulk supplies which they buy from Electrobras-controlled utilities. Second, tariffs are equal in the country as a whole regardless of differences in costs. Differences must be covered by the transfers between state utilities. Thus, there is also a significant horizontal financial inter-dependence in the sector. These institutional characteristics have been very important in the context of the present financial crisis

  9. Reliability of supply in competitive electricity markets: The Nordic electricity Market

    International Nuclear Information System (INIS)

    Singh, Balbir

    2005-12-01

    An overview of the current regulation and performance of the network utilities with respect to the reliability of supply across Europe in general indicates wide variation. On the regional level the situation in the Nordic market is no exception. Can the variation in reliability of supply in Nordic region be explained by differences in regulatory frameworks in the Nordic countries and is it possible to draw any best practice lessons for other countries and regions? The Norwegian regulation and performance with respect to reliability criterion is encouraging, however it must be emphasized that the Norwegian experience with reliability regulation in its current form covers a period of 3 years, a period that is too short to evaluate the Norwegian model. A closer examination of the Norwegian model reveals dynamic trade off in reliability performance, which if permanent may endanger the reliability of supply in the long-run. Last, but not the least important is the criterion that choice of regulation should be based on a careful social cost-benefit analysis of the regulatory model where both cost incurred by the regulatory agencies and the compliance costs incurred by the regulated utilities are included. A preliminary analysis of regulatory agencies in the Nordic market indicates that Norwegian model of network regulation is quite resource incentive. While it is premature to draw conclusions about the national regulatory mechanisms, the Nordic cross border regulation through voluntary arrangements under the auspices of NORDEL provides a good example of an arrangement that is useful when implementation of a formal regulatory regime across different jurisdiction is not possible

  10. An application of the fault tree analysis for the power system reliability estimation

    International Nuclear Information System (INIS)

    Volkanovski, A.; Cepin, M.; Mavko, B.

    2007-01-01

    The power system is a complex system with its main function to produce, transfer and provide consumers with electrical energy. Combinations of failures of components in the system can result in a failure of power delivery to certain load points and in some cases in a full blackout of power system. The power system reliability directly affects safe and reliable operation of nuclear power plants because the loss of offsite power is a significant contributor to the core damage frequency in probabilistic safety assessments of nuclear power plants. The method, which is based on the integration of the fault tree analysis with the analysis of the power flows in the power system, was developed and implemented for power system reliability assessment. The main contributors to the power system reliability are identified, both quantitatively and qualitatively. (author)

  11. Apollo Lunar Module Electrical Power System Overview

    Science.gov (United States)

    Interbartolo, Michael

    2009-01-01

    Objectives include: a) Describe LM Electrical System original specifications; b) Describe the decision to change from fuel cells to batteries and other changes; c) Describe the Electrical system; and d) Describe the Apollo 13 failure from the LM perspective.

  12. A model for reliability avaliation of the electrical supply source of the 1A3 and 1A4 control rods assemblies of Angra I reactor

    International Nuclear Information System (INIS)

    Yang, T.

    1978-01-01

    The reliability of the electrical power supply to the 4.16KV buses for the safety system operation of a nuclear power plant was studied. Particularly, Angra Unit I system was focused. Initially, reliability of each electrical supply source was estimated. Using a probabilistic approach based on the Markov processes, the system reliability was evaluated in terms of frequency and duration of loss of power supply and of the system failure probability evolution when one or more sources remained unavailable. Based on these results, certain reactor operating rules were proposed concerning later shutdown of the plant without compromising the nuclear reactor safety. A sensitivity analysis was also performed to show the different reliability parameter influences on final results. This analysis showed that the diesel system performs an important role in the power supply for a nuclear power plant [pt

  13. Reliability and availability requirements analysis for DEMO: fuel cycle system

    International Nuclear Information System (INIS)

    Pinna, T.; Borgognoni, F.

    2015-01-01

    The Demonstration Power Plant (DEMO) will be a fusion reactor prototype designed to demonstrate the capability to produce electrical power in a commercially acceptable way. Two of the key elements of the engineering development of the DEMO reactor are the definitions of reliability and availability requirements (or targets). The availability target for a hypothesized Fuel Cycle has been analysed as a test case. The analysis has been done on the basis of the experience gained in operating existing tokamak fusion reactors and developing the ITER design. Plant Breakdown Structure (PBS) and Functional Breakdown Structure (FBS) related to the DEMO Fuel Cycle and correlations between PBS and FBS have been identified. At first, a set of availability targets has been allocated to the various systems on the basis of their operating, protection and safety functions. 75% and 85% of availability has been allocated to the operating functions of fuelling system and tritium plant respectively. 99% of availability has been allocated to the overall systems in executing their safety functions. The chances of the systems to achieve the allocated targets have then been investigated through a Failure Mode and Effect Analysis and Reliability Block Diagram analysis. The following results have been obtained: 1) the target of 75% for the operations of the fuelling system looks reasonable, while the target of 85% for the operations of the whole tritium plant should be reduced to 80%, even though all the tritium plant systems can individually reach quite high availability targets, over 90% - 95%; 2) all the DEMO Fuel Cycle systems can reach the target of 99% in accomplishing their safety functions. (authors)

  14. Reliability and protection against failure in computer systems

    International Nuclear Information System (INIS)

    Daniels, B.K.

    1979-01-01

    Computers are being increasingly integrated into the control and safety systems of large and potentially hazardous industrial processes. This development introduces problems which are particular to computer systems and opens the way to new techniques of solving conventional reliability and availability problems. References to the developing fields of software reliability, human factors and software design are given, and these subjects are related, where possible, to the quantified assessment of reliability. Original material is presented in the areas of reliability growth and computer hardware failure data. The report draws on the experience of the National Centre of Systems Reliability in assessing the capability and reliability of computer systems both within the nuclear industry, and from the work carried out in other industries by the Systems Reliability Service. (author)

  15. Skylab technology electrical power system

    Science.gov (United States)

    Woosley, A. P.; Smith, O. B.; Nassen, H. S.

    1974-01-01

    The solar array/battery power systems for the Skylab vehicle were designed to operate in a solar inertial pointing mode to provide power continuously to the Skylab. Questions of power management are considered, taking into account difficulties caused by the reduction in power system performance due to the effects of structural failure occurring during the launching process. The performance of the solar array of the Apollo Telescope Mount Power System is discussed along with the Orbital Workshop solar array performance and the Airlock Module power conditioning group performance. A list is presented of a number of items which have been identified during mission monitoring and are recommended for electrical power system concepts, designs, and operation for future spacecraft.

  16. An integrated reliability management system for nuclear power plants

    International Nuclear Information System (INIS)

    Kimura, T.; Shimokawa, H.; Matsushima, H.

    1998-01-01

    The responsibility in the nuclear field of the Government, utilities and manufactures has increased in the past years due to the need of stable operation and great reliability of nuclear power plants. The need to improve the reliability is not only for the new plants but also for those now running. So, several measures have been taken to improve reliability. In particular, the plant manufactures have developed a reliability management system for each phase (planning, construction, maintenance and operation) and these have been integrated as a unified system. This integrated reliability management system for nuclear power plants contains information about plant performance, failures and incidents which have occurred in the plants. (author)

  17. Fatigue Reliability of Offshore Wind Turbine Systems

    DEFF Research Database (Denmark)

    Marquez-Dominguez, Sergio; Sørensen, John Dalsgaard

    2012-01-01

    of appropriate partial safety factors / fatigue design factors (FDF) for steel substructures of offshore wind turbines (OWTs). The fatigue life is modeled by the SN approach. Design and limit state equations are established based on the accumulated fatigue damage. The acceptable reliability level for optimal...... fatigue design of OWTs is discussed and results for reliability assessment of typical fatigue critical design of offshore steel support structures are presented....

  18. ELECTRICAL SUPPORT SYSTEM DESCRIPTION DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    S. Roy

    2004-06-24

    The purpose of this revision of the System Design Description (SDD) is to establish requirements that drive the design of the electrical support system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience/users are design engineers. This type of SDD both ''leads'' and ''trails'' the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. The SDD trails the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. Functional and operational requirements applicable to electrical support systems are obtained from the ''Project Functional and Operational Requirements'' (F&OR) (Siddoway 2003). Other requirements to support the design process have been taken from higher-level requirements documents such as the ''Project Design Criteria Document'' (PDC) (Doraswamy 2004), and fire hazards analyses. The above-mentioned low-level documents address ''Project Requirements Document'' (PRD) (Canon and Leitner 2003) requirements. This SDD contains several appendices that include supporting information. Appendix B lists key system charts, diagrams, drawings, and lists, and Appendix C includes a list of system procedures.

  19. ELECTRICAL SUPPORT SYSTEM DESCRIPTION DOCUMENT

    International Nuclear Information System (INIS)

    Roy, S.

    2004-01-01

    The purpose of this revision of the System Design Description (SDD) is to establish requirements that drive the design of the electrical support system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience/users are design engineers. This type of SDD both ''leads'' and ''trails'' the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. The SDD trails the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. Functional and operational requirements applicable to electrical support systems are obtained from the ''Project Functional and Operational Requirements'' (F andOR) (Siddoway 2003). Other requirements to support the design process have been taken from higher-level requirements documents such as the ''Project Design Criteria Document'' (PDC) (Doraswamy 2004), and fire hazards analyses. The above-mentioned low-level documents address ''Project Requirements Document'' (PRD) (Canon and Leitner 2003) requirements. This SDD contains several appendices that include supporting information. Appendix B lists key system charts, diagrams, drawings, and lists, and Appendix C includes a list of system procedures

  20. Powertrain system for a hybrid electric vehicle

    Science.gov (United States)

    Reed, Jr., Richard G.; Boberg, Evan S.; Lawrie, Robert E.; Castaing, Francois J.

    1999-08-31

    A hybrid electric powertrain system is provided including an electric motor/generator drivingly engaged with the drive shaft of a transmission. The electric is utilized for synchronizing the rotation of the drive shaft with the driven shaft during gear shift operations. In addition, a mild hybrid concept is provided which utilizes a smaller electric motor than typical hybrid powertrain systems. Because the electric motor is drivingly engaged with the drive shaft of the transmission, the electric motor/generator is driven at high speed even when the vehicle speed is low so that the electric motor/generator provides more efficient regeneration.

  1. Powertrain system for a hybrid electric vehicle

    Science.gov (United States)

    Reed, R.G. Jr.; Boberg, E.S.; Lawrie, R.E.; Castaing, F.J.

    1999-08-31

    A hybrid electric powertrain system is provided including an electric motor/generator drivingly engaged with the drive shaft of a transmission. The electric is utilized for synchronizing the rotation of the drive shaft with the driven shaft during gear shift operations. In addition, a mild hybrid concept is provided which utilizes a smaller electric motor than typical hybrid powertrain systems. Because the electric motor is drivingly engaged with the drive shaft of the transmission, the electric motor/generator is driven at high speed even when the vehicle speed is low so that the electric motor/generator provides more efficient regeneration. 34 figs.

  2. The electricity certificate system, 2009

    Energy Technology Data Exchange (ETDEWEB)

    Joehnemark, Maria; Oestberg, Roger; Johansson, Martin

    2009-07-01

    Over the years, the electricity certificate system has been maturing and consolidating, so that it is today an effective and functional policy measure that has won wide acceptance from all parties concerned. The long term approach and security of the system are attracting an increasing number of investors, which is described more fully in this report. This year's special theme chapter, Investing in Renewable Energy, presents the status of the system from an investment point of view. In addition to this chapter, the report includes, as always, an introduction to how the certificate system works, together with an updating with the latest statistics. A quick glance at external factors that can affect the system indicates that there are several that may do so in the future. Just the fact that the climate problem is still high on the political agenda, despite strong competition from economic crises, shows that there is a need for more renewable energy. The EU Renewable Energy Directive, which was adopted at the end of 2008, requires the Swedish energy system to deliver 49 % of its output from renewable sources by 2020. In addition, the Energy Bill adopted by the Swedish Parliament identifies the electricity certificate system as one of the most important means of achieving the country's objectives. Taken together, this indicates that there are many factors that will further strengthen the role of the certificate system in the next few years. If we look at the system itself, we can see that a number of important changes have been made since the previous report. With effect from 1st January 2009, the definition of electricity-intensive industries has changed, bringing it more closely in line with the definition used in energy taxation. Since 1st May, the rules have changed concerning entitlement to a new allocation period of certificates after a plant has been substantially modified. In addition, certificates can now be allocated for increases in output from

  3. Trends in probabilistic power system reliability analysis - a survey

    NARCIS (Netherlands)

    Tuinema, B.W.; Gibescu, M.; vd Meijden, M.A.M.M.; Kling, W.L.; Sluis, van der L.

    2011-01-01

    The electric power system is continually in development. Many of the developments will lead to an increase in the stress on the power system. For example, the increasing need for electrical energy, the transition to a sustainable energy supply and the liberalization of the electricity market all put

  4. Increasing the reliability of electric energy supply to consumers in ROMAG-PROD Heavy Water Plant

    International Nuclear Information System (INIS)

    Barta, Ioan; Hanes, Marian . E-mail electrica@romag.ro

    2004-01-01

    Full text: This work aims at achieving an analysis of time evolution of the status of electrical installations, their performances and reliability, at describing the refurbishment measures adopted, at assessing the efficiency of these measures and also to suggest solutions for improving the reliability in the electric energy supply of ROMAG-PROD Heavy Water Plant. The analysis started from the original design, the manner the electrical installations were mounted, the technological level of this equipment and gives an evaluation of the deficiencies and the evolution of incidents occurred during the operation period. On the basis of the experience gathered one advances new items for equipment renewing and refurbishment of electric installations which together with the existing ones would ensure an electric energy supply more secure and efficient, leading directly to a more safe and efficient operation of the ROMAG-PROD Heavy Water Plant. In this work the incidents of electric energy nature which occurred are analyzed, the equipment which generated events identified and measures to solve these problems proposed

  5. Preliminary investigation on reliability assessment of passive safety system

    International Nuclear Information System (INIS)

    Huang Changfan; Kuang Bo

    2012-01-01

    The reliability evaluation of passive safety system plays an important part in probabilistic safety assessment (PSA) of nuclear power plant applying passive safety design, which depends quantitatively on reliabilities of passive safety system. According to the object of reliability assessment of passive safety system, relevant parameters are identified. Then passive system behavior during accident scenarios are studied. A practical example of this method is given for the case of reliability assessment of AP1000 passive heat removal system in loss of normal feedwater accident. Key and design parameters of PRHRS are identified and functional failure criteria are established. Parameter combinations acquired by Latin hyper~ cube sampling (LHS) in possible parametric ranges are input and calculations of uncertainty propagation through RELAP5/MOD3 code are carried out. Based on the calculations, sensitivity assessment on PRHRS functional criteria and reliability evaluation of the system are presented, which might provide further PSA with PRHR system reliability. (authors)

  6. Reliability and maintainability assessment factors for reliable fault-tolerant systems

    Science.gov (United States)

    Bavuso, S. J.

    1984-01-01

    A long term goal of the NASA Langley Research Center is the development of a reliability assessment methodology of sufficient power to enable the credible comparison of the stochastic attributes of one ultrareliable system design against others. This methodology, developed over a 10 year period, is a combined analytic and simulative technique. An analytic component is the Computer Aided Reliability Estimation capability, third generation, or simply CARE III. A simulative component is the Gate Logic Software Simulator capability, or GLOSS. The numerous factors that potentially have a degrading effect on system reliability and the ways in which these factors that are peculiar to highly reliable fault tolerant systems are accounted for in credible reliability assessments. Also presented are the modeling difficulties that result from their inclusion and the ways in which CARE III and GLOSS mitigate the intractability of the heretofore unworkable mathematics.

  7. 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

  8. 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.

  9. Distribution system reliability evaluation using credibility theory | Xu ...

    African Journals Online (AJOL)

    In this paper, a hybrid algorithm based on fuzzy simulation and Failure Mode and Effect Analysis (FMEA) is applied to determine fuzzy reliability indices of distribution system. This approach can obtain fuzzy expected values and their variances of reliability indices, and the credibilities of reliability indices meeting specified ...

  10. Electric Vehicles in Power Systems with 50% Wind Power Penetration

    DEFF Research Database (Denmark)

    Østergaard, Jacob; Foosnæs, Anders; Xu, Zhao

    2009-01-01

    will be an important balancing measure to enable the Danish government’s energy strategy, which implies 50% wind power penetration in the electric power system. An EV will be a storage device for smoothing power fluctuations from renewable resources especially wind power and provide valuable system services...... for a reliable power system operation. Cost-benefit analysis shows that intelligent bidirectional charging – vehicle to grid (V2G) – provides a socio-economic profit of 150 million Euro/year in the Danish electric power system in 2025 assuming that 15% of the Danish road transport need is supplied by electricity....... This paper analyse the potential for using EVs in Denmark and identify the benefits of the electric power system with high wind power generation by intelligent charging of the EVs. Based on the analysis important technology gabs are identified, and the corresponding research and development initiatives...

  11. Solar energy thermally powered electrical generating system

    Science.gov (United States)

    Owens, William R. (Inventor)

    1989-01-01

    A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

  12. User's guide to the Reliability Estimation System Testbed (REST)

    Science.gov (United States)

    Nicol, David M.; Palumbo, Daniel L.; Rifkin, Adam

    1992-01-01

    The Reliability Estimation System Testbed is an X-window based reliability modeling tool that was created to explore the use of the Reliability Modeling Language (RML). RML was defined to support several reliability analysis techniques including modularization, graphical representation, Failure Mode Effects Simulation (FMES), and parallel processing. These techniques are most useful in modeling large systems. Using modularization, an analyst can create reliability models for individual system components. The modules can be tested separately and then combined to compute the total system reliability. Because a one-to-one relationship can be established between system components and the reliability modules, a graphical user interface may be used to describe the system model. RML was designed to permit message passing between modules. This feature enables reliability modeling based on a run time simulation of the system wide effects of a component's failure modes. The use of failure modes effects simulation enhances the analyst's ability to correctly express system behavior when using the modularization approach to reliability modeling. To alleviate the computation bottleneck often found in large reliability models, REST was designed to take advantage of parallel processing on hypercube processors.

  13. Incorporating reliability evaluation into the uncertainty analysis of electricity market price

    International Nuclear Information System (INIS)

    Kang, Chongqing; Bai, Lichao; Xia, Qing; Jiang, Jianjian; Zhao, Jing

    2005-01-01

    A novel model and algorithm for analyzing the uncertainties in electricity market is proposed in this paper. In this model, bidding decision is formulated as a probabilistic model that takes into account the decision-maker's willingness to bid, risk preferences, the fluctuation of fuel-price, etc. At the same time, generating unit's uncertain output model is considered by its forced outage rate (FOR). Based on the model, the uncertainty of market price is then analyzed. Taking the analytical results into consideration, not only the reliability of the power system can be conventionally analyzed, but also the possible distribution of market prices can be easily obtained. The probability distribution of market prices can be further used to calculate the expected output and the sales income of generating unit in the market. Based on these results, it is also possible to evaluate the risk involved by generating units. A simple system with four generating units is used to illustrate the proposed algorithm. The proposed algorithm and the modeling technique are expected to helpful to the market participants in making their economic decisions

  14. Quality electricity lines of external power systems electric traction DC

    Directory of Open Access Journals (Sweden)

    A.V. Petrov

    2012-08-01

    Full Text Available The results of studies that compare and analyze the numerical values of some key indicators quality electricity in the lines of the external power supply system the electric traction DC. As a supplement are additional and fundamental values of energy losses in them.

  15. How reliably can climate change and mitigation policy impacts on electric utilities be assessed?

    International Nuclear Information System (INIS)

    Dowlatabadi, H.; Kopp, R.J.; Palmer, K.; De Witt, D.

    1993-01-01

    Numerous mechanisms link climate change and electric utilities. Electricity generation releases radiatively active trace substances (RATS). Significant changes in atmospheric concentration of RATS can lead to a change in regional and global climate regimes. Mitigation action designed to prevent or limit climate change is possible through curbing emissions. Climate change and related mitigation actions impact on electric utilities. Foresight in electric utility planning requires reliable predictions of how the utilities may be affected in the decades ahead. In this paper the impacts of climate change and mitigation policies are noted, and our ability to assess these is reviewed. To this end a suite of models exploring supply and demand questions have been developed. The overall conclusion of the study is that the demand-side uncertainties dominate other unknowns and need to be better characterized and understood. (author)

  16. Wavelet-based information filtering for fault diagnosis of electric drive systems in electric ships.

    Science.gov (United States)

    Silva, Andre A; Gupta, Shalabh; Bazzi, Ali M; Ulatowski, Arthur

    2017-09-22

    Electric machines and drives have enjoyed extensive applications in the field of electric vehicles (e.g., electric ships, boats, cars, and underwater vessels) due to their ease of scalability and wide range of operating conditions. This stems from their ability to generate the desired torque and power levels for propulsion under various external load conditions. However, as with the most electrical systems, the electric drives are prone to component failures that can degrade their performance, reduce the efficiency, and require expensive maintenance. Therefore, for safe and reliable operation of electric vehicles, there is a need for automated early diagnostics of critical failures such as broken rotor bars and electrical phase failures. In this regard, this paper presents a fault diagnosis methodology for electric drives in electric ships. This methodology utilizes the two-dimensional, i.e. scale-shift, wavelet transform of the sensor data to filter optimal information-rich regions which can enhance the diagnosis accuracy as well as reduce the computational complexity of the classifier. The methodology was tested on sensor data generated from an experimentally validated simulation model of electric drives under various cruising speed conditions. The results in comparison with other existing techniques show a high correct classification rate with low false alarm and miss detection rates. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  17. Handbook of electrical power system dynamics modeling, stability, and control

    CERN Document Server

    Eremia, Mircea

    2013-01-01

    Complete guidance for understanding electrical power system dynamics and blackouts This handbook offers a comprehensive and up-to-date treatment of power system dynamics. Addressing the full range of topics, from the fundamentals to the latest technologies in modeling, stability, and control, Handbook of Electrical Power System Dynamics provides engineers with hands-on guidance for understanding the phenomena leading to blackouts so they can design the most appropriate solutions for a cost-effective and reliable operation. Focusing on system dynamics, the book details

  18. Scoping study on trends in the economic value of electricity reliability to the U.S. economy; TOPICAL

    International Nuclear Information System (INIS)

    Eto, Joseph; Koomey, Jonathan; Lehman, Bryan; Martin, Nathan; Mills, Evan; Webber, Carrie; Worrell, Ernst

    2001-01-01

    During the past three years, working with more than 150 organizations representing public and private stakeholders, EPRI has developed the Electricity Technology Roadmap. The Roadmap identifies several major strategic challenges that must be successfully addressed to ensure a sustainable future in which electricity continues to play an important role in economic growth. Articulation of these anticipated trends and challenges requires a detailed understanding of the role and importance of reliable electricity in different sectors of the economy. This report is intended to contribute to that understanding by analyzing key aspects of trends in the economic value of electricity reliability in the U.S. economy. We first present a review of recent literature on electricity reliability costs. Next, we describe three distinct end-use approaches for tracking trends in reliability needs: (1) an analysis of the electricity-use requirements of office equipment in different commercial sectors; (2) an examination of the use of aggregate statistical indicators of industrial electricity use and economic activity to identify high reliability-requirement customer market segments; and (3) a case study of cleanrooms, which is a cross-cutting market segment known to have high reliability requirements. Finally, we present insurance industry perspectives on electricity reliability as an example of a financial tool for addressing customers' reliability needs

  19. Scoping study on trends in the economic value of electricity reliability to the U.S. economy

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph; Koomey, Jonathan; Lehman, Bryan; Martin, Nathan; Mills, Evan; Webber, Carrie; Worrell, Ernst

    2001-06-01

    During the past three years, working with more than 150 organizations representing public and private stakeholders, EPRI has developed the Electricity Technology Roadmap. The Roadmap identifies several major strategic challenges that must be successfully addressed to ensure a sustainable future in which electricity continues to play an important role in economic growth. Articulation of these anticipated trends and challenges requires a detailed understanding of the role and importance of reliable electricity in different sectors of the economy. This report is intended to contribute to that understanding by analyzing key aspects of trends in the economic value of electricity reliability in the U.S. economy. We first present a review of recent literature on electricity reliability costs. Next, we describe three distinct end-use approaches for tracking trends in reliability needs: (1) an analysis of the electricity-use requirements of office equipment in different commercial sectors; (2) an examination of the use of aggregate statistical indicators of industrial electricity use and economic activity to identify high reliability-requirement customer market segments; and (3) a case study of cleanrooms, which is a cross-cutting market segment known to have high reliability requirements. Finally, we present insurance industry perspectives on electricity reliability as an example of a financial tool for addressing customers' reliability needs.

  20. Time domain series system definition and gear set reliability modeling

    International Nuclear Information System (INIS)

    Xie, Liyang; Wu, Ningxiang; Qian, Wenxue

    2016-01-01

    Time-dependent multi-configuration is a typical feature for mechanical systems such as gear trains and chain drives. As a series system, a gear train is distinct from a traditional series system, such as a chain, in load transmission path, system-component relationship, system functioning manner, as well as time-dependent system configuration. Firstly, the present paper defines time-domain series system to which the traditional series system reliability model is not adequate. Then, system specific reliability modeling technique is proposed for gear sets, including component (tooth) and subsystem (tooth-pair) load history description, material priori/posterior strength expression, time-dependent and system specific load-strength interference analysis, as well as statistically dependent failure events treatment. Consequently, several system reliability models are developed for gear sets with different tooth numbers in the scenario of tooth root material ultimate tensile strength failure. The application of the models is discussed in the last part, and the differences between the system specific reliability model and the traditional series system reliability model are illustrated by virtue of several numerical examples. - Highlights: • A new type of series system, i.e. time-domain multi-configuration series system is defined, that is of great significance to reliability modeling. • Multi-level statistical analysis based reliability modeling method is presented for gear transmission system. • Several system specific reliability models are established for gear set reliability estimation. • The differences between the traditional series system reliability model and the new model are illustrated.

  1. Thermal Management and Reliability of Automotive Power Electronics and Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, Sreekant V [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bennion, Kevin S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cousineau, Justine E [National Renewable Energy Laboratory (NREL), Golden, CO (United States); DeVoto, Douglas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Feng, Xuhui [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kekelia, Bidzina [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kozak, Joseph P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Major, Joshua [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Moreno, Gilberto [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Paret, Paul P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tomerlin, Jeff J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-02-09

    Low-cost, high-performance thermal management technologies are helping meet aggressive power density, specific power, cost, and reliability targets for power electronics and electric machines. The National Renewable Energy Laboratory is working closely with numerous industry and research partners to help influence development of components that meet aggressive performance and cost targets through development and characterization of cooling technologies, and thermal characterization and improvements of passive stack materials and interfaces. Thermomechanical reliability and lifetime estimation models are important enablers for industry in cost-and time-effective design.

  2. Maximising water supply system yield subject to multiple reliability ...

    African Journals Online (AJOL)

    Maximising water supply system yield subject to multiple reliability constraints via simulation-optimisation. ... Water supply systems have to satisfy different demands that each require various levels of reliability ... and monthly operating rules that maximise the yield of a water supply system subject to ... HOW TO USE AJOL.

  3. Reliability assessment of restructured power systems using reliability network equivalent and pseudo-sequential simulation techniques

    International Nuclear Information System (INIS)

    Ding, Yi; Wang, Peng; Goel, Lalit; Billinton, Roy; Karki, Rajesh

    2007-01-01

    This paper presents a technique to evaluate reliability of a restructured power system with a bilateral market. The proposed technique is based on the combination of the reliability network equivalent and pseudo-sequential simulation approaches. The reliability network equivalent techniques have been implemented in the Monte Carlo simulation procedure to reduce the computational burden of the analysis. Pseudo-sequential simulation has been used to increase the computational efficiency of the non-sequential simulation method and to model the chronological aspects of market trading and system operation. Multi-state Markov models for generation and transmission systems are proposed and implemented in the simulation. A new load shedding scheme is proposed during generation inadequacy and network congestion to minimize the load curtailment. The IEEE reliability test system (RTS) is used to illustrate the technique. (author)

  4. Reliability Prediction Of System And Component Of Process System Of RSG-GAS Reactor

    International Nuclear Information System (INIS)

    Sitorus Pane, Jupiter

    2001-01-01

    The older the reactor the higher the probability of the system and components suffer from loss of function or degradation. This phenomenon occurred because of wear, corrosion, and fatigue. Study on component reliability was generally performed deterministically and statistically. This paper would describe an analysis of using statistical method, i.e. regression Cox, in order to predict the reliability of the components and their environmental influence's factors. The result showed that the dynamics, non safety related, and mechanic components have higher risk of failure, whereas static, safety related, and electric have lower risk of failures. The relative risk value for variable of components dynamics, quality, dummy 1 and dummy 2 are of 1.54, 1.59, 1.50, and 0.83 compare to other components type with each variable. Component with the higher risk have lower reliability than lower one

  5. Reliability modelling and simulation of switched linear system ...

    African Journals Online (AJOL)

    Reliability modelling and simulation of switched linear system control using temporal databases. ... design of fault-tolerant real-time switching systems control and modelling embedded micro-schedulers for complex systems maintenance.

  6. Electric power supply and demand 1979 to 1988 for the contiguous United States as projected by the Regional Electric Reliability Councils in their April 1, 1979 long-range coordinated planning reports to the Department of Energy

    Energy Technology Data Exchange (ETDEWEB)

    Savage, N.; Graban, W.

    1979-12-01

    Information concerning bulk electric power supply and demand is summarized and reviewed. Electric-utility power-supply systems are composed of power sources, transmission and distribution facilities, and users of electricity. In the United States there are three such systems of large geographic extent that together cover the entire country. Subjects covered are: energy forecasts, peak demand forecasts, generating-capacity forecasts, purchases and sales of capacity, and transmission. Extensive data are compiled in 17 tables. Information in two appendices includes a general description of the Regional Electric Reliability Councils and US generating capacity as of June 30, 1979. 3 figures, 17 tables.

  7. Hybrid electric vehicle power management system

    Science.gov (United States)

    Bissontz, Jay E.

    2015-08-25

    Level voltage levels/states of charge are maintained among a plurality of high voltage DC electrical storage devices/traction battery packs that are arrayed in series to support operation of a hybrid electric vehicle drive train. Each high voltage DC electrical storage device supports a high voltage power bus, to which at least one controllable load is connected, and at least a first lower voltage level electrical distribution system. The rate of power transfer from the high voltage DC electrical storage devices to the at least first lower voltage electrical distribution system is controlled by DC-DC converters.

  8. The use of reliability analysis techniques applied to nuclear power station emergency core cooling systems

    International Nuclear Information System (INIS)

    Danielsen, A.; Snaith, E.R.

    1975-01-01

    A reliability investigation carried out by the Safety and Reliability Services of the UKAEA, and the SSEB, of the essential system/reactor coolant system for a large nuclear power station is described. In AGR type reactors, after all reactor shutdown conditions, it is necessary to restore forced gas circulation and sufficient boiler feed to maintain the heat removal capacity of the boilers. The coolant requirements are provided by several independent mechanical systems of primary coolant fans, feedwater pumps, and valves integrated with electrical power sources, switchgear, and automatic control equipment. Reliability is treated as one aspect of system performance and quantified in terms of failure to meet a specific objective. Based on the reliability performance of the constituent components the optimum system configuration is determined together with the preferred plant operating procedures and maintenance requirements. (author)

  9. Probabilistic Fault Diagnosis in Electrical Power Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — Electrical power systems play a critical role in spacecraft and aircraft. This paper discusses our development of a diagnostic capability for an electrical power...

  10. Centralised and distributed electricity systems

    International Nuclear Information System (INIS)

    Bouffard, Francois; Kirschen, Daniel S.

    2008-01-01

    Because of their high level of integration, centralised energy supply systems are vulnerable to disturbances in the supply chain. In the case of electricity especially, this supply paradigm is losing some of its appeal. Apart from vulnerability, a number of further aggravating factors are reducing its attractiveness. They include the depletion of fossil fuels and their climate change impact, the insecurities affecting energy transportation infrastructure, and the desire of investors to minimise risks through the deployment of smaller-scale, modular generation and transmission systems. Small-scale decentralised systems, where energy production and consumption are usually tightly coupled, are emerging as a viable alternative. They are less dependent upon centralised energy supply, and can sometimes use more than one energy source. They are less sensitive to the uncertain availability of remote primary energy and transportation networks. In addition, the close connection between energy generation and use makes decentralised systems cleaner because they are most often based on renewable energies or on high-efficiency fossil fuel-based technologies such as combined heat and power (CHP). Fully decentralised energy supply is not currently possible or even truly desirable. The secure and clean energy systems of the future will be those flexible enough to allow for a spectrum of hybrid modes of operation and investment, combining the best attributes of both paradigms. A large part of this flexibility will come from the networks that make it possible to combine these two types of infrastructures and obtain the benefits of both approaches

  11. A strategic review of electricity systems models

    International Nuclear Information System (INIS)

    Foley, A.M.; O Gallachoir, B.P.; McKeogh, E.J.; Hur, J.; Baldick, R.

    2010-01-01

    Electricity systems models are software tools used to manage electricity demand and the electricity systems, to trade electricity and for generation expansion planning purposes. Various portfolios and scenarios are modelled in order to compare the effects of decision making in policy and on business development plans in electricity systems so as to best advise governments and industry on the least cost economic and environmental approach to electricity supply, while maintaining a secure supply of sufficient quality electricity. The modelling techniques developed to study vertically integrated state monopolies are now applied in liberalised markets where the issues and constraints are more complex. This paper reviews the changing role of electricity systems modelling in a strategic manner, focussing on the modelling response to key developments, the move away from monopoly towards liberalised market regimes and the increasing complexity brought about by policy targets for renewable energy and emissions. The paper provides an overview of electricity systems modelling techniques, discusses a number of key proprietary electricity systems models used in the USA and Europe and provides an information resource to the electricity analyst not currently readily available in the literature on the choice of model to investigate different aspects of the electricity system. (author)

  12. Reliability assessment of distribution system with the integration of renewable distributed generation

    International Nuclear Information System (INIS)

    Adefarati, T.; Bansal, R.C.

    2017-01-01

    Highlights: • Addresses impacts of renewable DG on the reliability of the distribution system. • Multi-objective formulation for maximizing the cost saving with integration of DG. • Uses Markov model to study the stochastic characteristics of the major components. • The investigation is done using modified RBTS bus test distribution system. • Proposed approach is useful for electric utilities to enhance the reliability. - Abstract: Recent studies have shown that renewable energy resources will contribute substantially to future energy generation owing to the rapid depletion of fossil fuels. Wind and solar energy resources are major sources of renewable energy that have the ability to reduce the energy crisis and the greenhouse gases emitted by the conventional power plants. Reliability assessment is one of the key indicators to measure the impact of the renewable distributed generation (DG) units in the distribution networks and to minimize the cost that is associated with power outage. This paper presents a comprehensive reliability assessment of the distribution system that satisfies the consumer load requirements with the penetration of wind turbine generator (WTG), electric storage system (ESS) and photovoltaic (PV). A Markov model is proposed to access the stochastic characteristics of the major components of the renewable DG resources as well as their influence on the reliability of a conventional distribution system. The results obtained from the case studies have demonstrated the effectiveness of using WTG, ESS and PV to enhance the reliability of the conventional distribution system.

  13. Design requirement for electrical system of an advanced research reactor

    International Nuclear Information System (INIS)

    Jung, Hoan Sung; Kim, H. K.; Kim, Y. K.; Wu, J. S.; Ryu, J. S.

    2004-12-01

    An advanced research reactor is being designed since 2002 and the conceptual design has been completed this year for the several types of core. Also the fuel was designed for the potential cores. But the process system, the I and C system, and the electrical system design are under pre-conceptual stage. The conceptual design for those systems will be developed in the next year. Design requirements for the electrical system set up to develop conceptual design. The same goals as reactor design - enhance safety, reliability, economy, were applied for the development of the requirements. Also the experience of HANARO design and operation was based on. The design requirements for the power distribution, standby power supply, and raceway system will be used for the conceptual design of electrical system

  14. Design requirement for electrical system of an advanced research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hoan Sung; Kim, H. K.; Kim, Y. K.; Wu, J. S.; Ryu, J. S

    2004-12-01

    An advanced research reactor is being designed since 2002 and the conceptual design has been completed this year for the several types of core. Also the fuel was designed for the potential cores. But the process system, the I and C system, and the electrical system design are under pre-conceptual stage. The conceptual design for those systems will be developed in the next year. Design requirements for the electrical system set up to develop conceptual design. The same goals as reactor design - enhance safety, reliability, economy, were applied for the development of the requirements. Also the experience of HANARO design and operation was based on. The design requirements for the power distribution, standby power supply, and raceway system will be used for the conceptual design of electrical system.

  15. The contribution of instrumentation and control software to system reliability

    International Nuclear Information System (INIS)

    Fryer, M.O.

    1984-01-01

    Advanced instrumentation and control systems are usually implemented using computers that monitor the instrumentation and issue commands to control elements. The control commands are based on instrument readings and software control logic. The reliability of the total system will be affected by the software design. When comparing software designs, an evaluation of how each design can contribute to the reliability of the system is desirable. Unfortunately, the science of reliability assessment of combined hardware and software systems is in its infancy. Reliability assessment of combined hardware/software systems is often based on over-simplified assumptions about software behavior. A new method of reliability assessment of combined software/hardware systems is presented. The method is based on a procedure called fault tree analysis which determines how component failures can contribute to system failure. Fault tree analysis is a well developed method for reliability assessment of hardware systems and produces quantitative estimates of failure probability based on component failure rates. It is shown how software control logic can be mapped into a fault tree that depicts both software and hardware contributions to system failure. The new method is important because it provides a way for quantitatively evaluating the reliability contribution of software designs. In many applications, this can help guide designers in producing safer and more reliable systems. An application to the nuclear power research industry is discussed

  16. Electric vehicle system for charging and supplying electrical power

    Science.gov (United States)

    Su, Gui Jia

    2010-06-08

    A power system that provides power between an energy storage device, an external charging-source/load, an onboard electrical power generator, and a vehicle drive shaft. The power system has at least one energy storage device electrically connected across a dc bus, at least one filter capacitor leg having at least one filter capacitor electrically connected across the dc bus, at least one power inverter/converter electrically connected across the dc bus, and at least one multiphase motor/generator having stator windings electrically connected at one end to form a neutral point and electrically connected on the other end to one of the power inverter/converters. A charging-sourcing selection socket is electrically connected to the neutral points and the external charging-source/load. At least one electronics controller is electrically connected to the charging-sourcing selection socket and at least one power inverter/converter. The switch legs in each of the inverter/converters selected by the charging-source/load socket collectively function as a single switch leg. The motor/generators function as an inductor.

  17. ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    M. Maniyar

    2004-06-22

    The purpose of this revision of the System Description Document (SDD) is to establish requirements that drive the design of the electrical power system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience are design engineers. This type of SDD leads and follows the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential to performing the design process. This SDD follows the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. Functional and operational requirements applicable to this system are obtained from ''Project Functional and Operational Requirements'' (F&OR) (Siddoway, 2003). Other requirements to support the design process have been taken from higher level requirements documents such as ''Project Design Criteria Document'' (PDC) (Doraswamy 2004), the fire hazards analyses, and the preclosure safety analysis. The above mentioned low-level documents address ''Project Requirements Document'' (PRD) (Canori and Leitner 2003) requirements. This SDD includes several appendices with supporting information. Appendix B lists key system charts, diagrams, drawings, and lists; and Appendix C is a list of system procedures.

  18. Strategic bidding of generating units in competitive electricity market with considering their reliability

    International Nuclear Information System (INIS)

    Soleymani, S.; Ranjbar, A.M.; Shirani, A.R.

    2008-01-01

    In the restructured power systems, they are typically scheduled based on the offers and bids to buy and sell energy and ancillary services (AS) subject to operational and security constraints. Generally, no account is taken of unit reliability when scheduling it. Therefore generating units have no incentive to improve their reliability. This paper proposes a new method to obtain the equilibrium points for reliability and price bidding strategy of units when the unit reliability is considered in the scheduling problem. The proposed methodology employs the supply function equilibrium (SFE) for modeling a unit's bidding strategy. Units change their bidding strategies and improve their reliability until Nash equilibrium points are obtained. GAMS (general algebraic modeling system) language has been used to solve the market scheduling problem using DICOPT optimization software with mixed integer non-linear programming. (author)

  19. System 80+ Design and Licensing : Improving Plant Reliability

    International Nuclear Information System (INIS)

    Newman, Robert E.

    1989-01-01

    The U. S. nuclear industry is striving to improve plant reliability and availability through improved plant design, component designs and plant maintenance. In an effort to improve safety and to demonstrate that commercial nuclear power is economically competitive with other energy sources, the utilities, nuclear vendors, architect engineers and constructors, and component suppliers are all participating in an industry-wide effort to develop improved Light Water Reactor (LWR) designs that are based upon the many years of successful LWR operation. In an age when the world faces the environmental pressures of the greenhouse effect and acid rain, electricity generated from nuclear energy must play an increasing role in the energy picture of Korea, the United States and the rest of the world. This paper discusses the plant availability requirement that has been established by the industry-wide effort mentioned above. After briefly describing Combustion Engineering's program for development of the System 80 Plus standard design and the participation of the Korea Advanced Energy Research Institute (KAERI) in the program, the paper then describes the design features that are being incorporated into System 80+. The industry ALRR Program has established a very ambitious criterion of 87% for the plant availability of future nuclear units. To satisfy such a requirement, the next generation of nuclear plants will include a great many design improvements that reflect the hundreds of years of operating experience that we have accrued. C-ESA's System 80+ will include a number of design changes that improve operating margins and make the plant easier to operate and maintain. Not surprisingly, there is a great deal of overlap between improved safety and improved reliability. In the end, our design will satisfy the future needs of the utilities, the regulators, and the public. C-E is very pleased that KAERI is working with US to achieve these important goals

  20. Wireless distributed functional electrical stimulation system

    Directory of Open Access Journals (Sweden)

    Jovičić Nenad S

    2012-08-01

    Full Text Available Abstract Background The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. Methods The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype’s software. Results The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers. One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. Conclusions The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.

  1. Wireless distributed functional electrical stimulation system.

    Science.gov (United States)

    Jovičić, Nenad S; Saranovac, Lazar V; Popović, Dejan B

    2012-08-09

    The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype's software. The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers). One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.

  2. Underwater electric field detection system based on weakly electric fish

    Science.gov (United States)

    Xue, Wei; Wang, Tianyu; Wang, Qi

    2018-04-01

    Weakly electric fish sense their surroundings in complete darkness by their active electric field detection system. However, due to the insufficient detection capacity of the electric field, the detection distance is not enough, and the detection accuracy is not high. In this paper, a method of underwater detection based on rotating current field theory is proposed to improve the performance of underwater electric field detection system. First of all, we built underwater detection system based on the theory of the spin current field mathematical model with the help of the results of previous researchers. Then we completed the principle prototype and finished the metal objects in the water environment detection experiments, laid the foundation for the further experiments.

  3. Automated Energy Distribution and Reliability System: Validation Integration - Results of Future Architecture Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Buche, D. L.

    2008-06-01

    This report describes Northern Indiana Public Service Co. project efforts to develop an automated energy distribution and reliability system. The purpose of this project was to implement a database-driven GIS solution that would manage all of the company's gas, electric, and landbase objects. This report is second in a series of reports detailing this effort.

  4. Concept report: Microprocessor control of electrical power system

    Science.gov (United States)

    Perry, E.

    1977-01-01

    An electrical power system which uses a microprocessor for systems control and monitoring is described. The microprocessor controlled system permits real time modification of system parameters for optimizing a system configuration, especially in the event of an anomaly. By reducing the components count, the assembling and testing of the unit is simplified, and reliability is increased. A resuable modular power conversion system capable of satisfying a large percentage of space applications requirements is examined along with the programmable power processor. The PC global controller which handles systems control and external communication is analyzed, and a software description is given. A systems application summary is also included.

  5. The electrical system of nuclear power plant

    International Nuclear Information System (INIS)

    Firman Silitonga; Gunarwan Prayitno

    2009-01-01

    In these system, electrical power system is supplied from two-offsite transmission system respective main transformer and house service transformer; and reserve transformer. The electrical load in these system consist of safety electrical system and non-safety electrical system, The safety electrical and non safety electrical systems consist of four 6,9 kV AC medium voltage bus and 480 V AC low voltage bus system. The DC power system consist of four safety 125 V DC power system and the two non-safety 125 DC power systems. The equipment in these electrical system is main turbine-generator; GTG safety; GTG alternate; uninterrupted power supply (UPS) and battery system. To protect electrical equipment and building to direct stroke and non direct stroke disturbances is installed netral grounding system and lightning protection and protection the personnel to touch-voltage is installed equipment grounding system and station grounding. The lightning arrester system is connected to station station grounding system. (author)

  6. Report on emergency electrical power supply systems for nuclear fuel cycle and reactor facilities security systems

    International Nuclear Information System (INIS)

    1977-01-01

    The report includes information that will be useful to those responsible for the planning, design and implementation of emergency electric power systems for physical security and special nuclear materials accountability systems. Basic considerations for establishing the system requirements for emergency electric power for security and accountability operations are presented. Methods of supplying emergency power that are available at present and methods predicted to be available in the future are discussed. The characteristics of capacity, cost, safety, reliability and environmental and physical facility considerations of emergency electric power techniques are presented. The report includes basic considerations for the development of a system concept and the preparation of a detailed system design

  7. Report on emergency electrical power supply systems for nuclear fuel cycle and reactor facilities security systems

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    The report includes information that will be useful to those responsible for the planning, design and implementation of emergency electric power systems for physical security and special nuclear materials accountability systems. Basic considerations for establishing the system requirements for emergency electric power for security and accountability operations are presented. Methods of supplying emergency power that are available at present and methods predicted to be available in the future are discussed. The characteristics of capacity, cost, safety, reliability and environmental and physical facility considerations of emergency electric power techniques are presented. The report includes basic considerations for the development of a system concept and the preparation of a detailed system design.

  8. A computational Bayesian approach to dependency assessment in system reliability

    International Nuclear Information System (INIS)

    Yontay, Petek; Pan, Rong

    2016-01-01

    Due to the increasing complexity of engineered products, it is of great importance to develop a tool to assess reliability dependencies among components and systems under the uncertainty of system reliability structure. In this paper, a Bayesian network approach is proposed for evaluating the conditional probability of failure within a complex system, using a multilevel system configuration. Coupling with Bayesian inference, the posterior distributions of these conditional probabilities can be estimated by combining failure information and expert opinions at both system and component levels. Three data scenarios are considered in this study, and they demonstrate that, with the quantification of the stochastic relationship of reliability within a system, the dependency structure in system reliability can be gradually revealed by the data collected at different system levels. - Highlights: • A Bayesian network representation of system reliability is presented. • Bayesian inference methods for assessing dependencies in system reliability are developed. • Complete and incomplete data scenarios are discussed. • The proposed approach is able to integrate reliability information from multiple sources at multiple levels of the system.

  9. Research Study Towards a MEFFV Electric Armament System

    National Research Council Canada - National Science Library

    Pappas, J

    2004-01-01

    .... One vehicle variant seeks to exploit synergies between electric mobility and electric armament systems by employing a hybrid electric mobility propulsion system and an electric gun for an all Electric MEFFV...

  10. Electric propulsion reliability: Statistical analysis of on-orbit anomalies and comparative analysis of electric versus chemical propulsion failure rates

    Science.gov (United States)

    Saleh, Joseph Homer; Geng, Fan; Ku, Michelle; Walker, Mitchell L. R.

    2017-10-01

    With a few hundred spacecraft launched to date with electric propulsion (EP), it is possible to conduct an epidemiological study of EP's on orbit reliability. The first objective of the present work was to undertake such a study and analyze EP's track record of on orbit anomalies and failures by different covariates. The second objective was to provide a comparative analysis of EP's failure rates with those of chemical propulsion. Satellite operators, manufacturers, and insurers will make reliability- and risk-informed decisions regarding the adoption and promotion of EP on board spacecraft. This work provides evidence-based support for such decisions. After a thorough data collection, 162 EP-equipped satellites launched between January 1997 and December 2015 were included in our dataset for analysis. Several statistical analyses were conducted, at the aggregate level and then with the data stratified by severity of the anomaly, by orbit type, and by EP technology. Mean Time To Anomaly (MTTA) and the distribution of the time to (minor/major) anomaly were investigated, as well as anomaly rates. The important findings in this work include the following: (1) Post-2005, EP's reliability has outperformed that of chemical propulsion; (2) Hall thrusters have robustly outperformed chemical propulsion, and they maintain a small but shrinking reliability advantage over gridded ion engines. Other results were also provided, for example the differentials in MTTA of minor and major anomalies for gridded ion engines and Hall thrusters. It was shown that: (3) Hall thrusters exhibit minor anomalies very early on orbit, which might be indicative of infant anomalies, and thus would benefit from better ground testing and acceptance procedures; (4) Strong evidence exists that EP anomalies (onset and likelihood) and orbit type are dependent, a dependence likely mediated by either the space environment or differences in thrusters duty cycles; (5) Gridded ion thrusters exhibit both

  11. Systems reliability analysis for the national ignition facility

    International Nuclear Information System (INIS)

    Majumdar, K.C.; Annese, C.E.; MacIntyre, A.T.; Sicherman, A.

    1996-01-01

    A Reliability, Availability and Maintainability (RAM) analysis was initiated for the National Ignition Facility (NIF). The NIF is an inertial confinement fusion research facility designed to achieve controlled thermonuclear reaction; the preferred site for the NIF is the Lawrence Livermore National Laboratory (LLNL). The NIF RAM analysis has three purposes: (1) to allocate top level reliability and availability goals for the systems, (2) to develop an operability model for optimum maintainability, and (3) to determine the achievability of the allocated goals of the RAM parameters for the NIF systems and the facility operation as a whole. An allocation model assigns the reliability and availability goals for front line and support systems by a top-down approach; reliability analysis uses a bottom-up approach to determine the system reliability and availability from component level to system level

  12. The reliability of nuclear power plant safety systems

    International Nuclear Information System (INIS)

    Susnik, J.

    1978-01-01

    A criterion was established concerning the protection that nuclear power plant (NPP) safety systems should afford. An estimate of the necessary or adequate reliability of the total complex of safety systems was derived. The acceptable unreliability of auxiliary safety systems is given, provided the reliability built into the specific NPP safety systems (ECCS, Containment) is to be fully utilized. A criterion for the acceptable unreliability of safety (sub)systems which occur in minimum cut sets having three or more components of the analysed fault tree was proposed. A set of input MTBF or MTTF values which fulfil all the set criteria and attain the appropriate overall reliability was derived. The sensitivity of results to input reliability data values was estimated. Numerical reliability evaluations were evaluated by the programs POTI, KOMBI and particularly URSULA, the last being based on Vesely's kinetic fault tree theory. (author)

  13. Some areas of reliability technique which have been neglected to some extent - maintainability - human reliability - mechanical reliability - repairable systems

    International Nuclear Information System (INIS)

    Akersten, P.A.

    1985-01-01

    The present thesis consists of four papers, three of which are of a expositary nature and one more theoretical. The first two papers have a natural coupling to the man-machine interface. The first paper is devoted to the concept of maintainability and the role of man as maintenance technician. The second paper discusses aspects of human reliability, mainly studying man as operator. However, maintenance tasks can be studied in the same manner. The third paper concerns reliability prediction for mechanical components. This is an area of vital importance for the reliability practitioner, who needs realistic and easy-to-use mathematical models for different failure modes. The fourth paper discusses mathematical models for repairable systems, especially the problem of testing whether a constant event intensity model is adequate or not. (author)

  14. System Reliability of Timber Structures with Ductile Behaviour

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Čizmar, Dean

    2011-01-01

    The present paper considers the evaluation of timber structures with the focus on robustness due to connection ductility. The robustness analysis is based on the structural reliability framework applied to a simplified mechanical system. The structural timber system is depicted as a parallel system....... An evaluation method of the ductile behaviour is introduced. For different ductile behaviours, the system reliability is estimated based on Monte Carlo simulation. A correlation between the strength of the structural elements is introduced. The results indicate that the reliability of a structural timber system...

  15. Air pollution restrictions in electrical production system

    International Nuclear Information System (INIS)

    Gallizioli, G.

    1993-01-01

    A description of the principal characteristics regarding the Italian electrical power system and the evolution of standardization in air pollution control is given. Afterwards, ENEL (the Italian National Electricity Board) actions in the environmental protection field (with particular respect to thermo-electrical production) are presented. Finally, principal ENEL research programs on new air pollution control technologies are discussed

  16. thermal power stations' reliability evaluation in a hydrothermal system

    African Journals Online (AJOL)

    Dr Obe

    A quantitative tool for the evaluation of thermal power stations reliability in a hydrothermal system is presented. ... (solar power); wind (wind power) and the rest, thermal power and ... probability of a system performing its function adequately for ...

  17. Results of a Demonstration Assessment of Passive System Reliability Utilizing the Reliability Method for Passive Systems (RMPS)

    Energy Technology Data Exchange (ETDEWEB)

    Bucknor, Matthew; Grabaskas, David; Brunett, Acacia; Grelle, Austin

    2015-04-26

    Advanced small modular reactor designs include many advantageous design features such as passively driven safety systems that are arguably more reliable and cost effective relative to conventional active systems. Despite their attractiveness, a reliability assessment of passive systems can be difficult using conventional reliability methods due to the nature of passive systems. Simple deviations in boundary conditions can induce functional failures in a passive system, and intermediate or unexpected operating modes can also occur. As part of an ongoing project, Argonne National Laboratory is investigating various methodologies to address passive system reliability. The Reliability Method for Passive Systems (RMPS), a systematic approach for examining reliability, is one technique chosen for this analysis. This methodology is combined with the Risk-Informed Safety Margin Characterization (RISMC) approach to assess the reliability of a passive system and the impact of its associated uncertainties. For this demonstration problem, an integrated plant model of an advanced small modular pool-type sodium fast reactor with a passive reactor cavity cooling system is subjected to a station blackout using RELAP5-3D. This paper discusses important aspects of the reliability assessment, including deployment of the methodology, the uncertainty identification and quantification process, and identification of key risk metrics.

  18. Advanced electrical power system technology for the all electric aircraft

    Science.gov (United States)

    Finke, R. C.; Sundberg, G. R.

    1983-01-01

    The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg. Previously announced in STAR as N83-24764

  19. Advanced electrical power system technology for the all electric aircraft

    Science.gov (United States)

    Finke, R. C.; Sundberg, G. R.

    1983-01-01

    The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg.

  20. Thermo-electrical systems for the generation of electricity

    International Nuclear Information System (INIS)

    Bitschi, A.; Froehlich, K.

    2010-01-01

    This article takes a look at theoretical models concerning thermo-electrical systems for the generation of electricity and demonstrations of technology actually realised. The potentials available and developments are discussed. The efficient use of energy along the whole generation and supply chain, as well as the use of renewable energy sources are considered as being two decisive factors in the attainment of a sustainable energy supply system. The large amount of unused waste heat available today in energy generation, industrial processes, transport systems and public buildings is commented on. Thermo-electric conversion systems are discussed and work being done on the subject at the Swiss Federal Institute of Technology in Zurich is discussed. The findings are discussed and results are presented in graphical form

  1. Electric cars as mobile power storage systems

    International Nuclear Information System (INIS)

    Herzog, B.

    2010-01-01

    This article discusses the use of electric cars as a means of optimising the use of renewable energy sources. Charging the cars' batteries during periods when cheap electricity prices prevail and then using excess capacity to supply the mains with electricity during periods of peak demand is discussed. The possible use of wind for power generation is discussed and a system proposed by a leading supplier of electrical apparatus and systems is examined. Two examples of electric cars and associated power chains are looked at and tests in everyday practice are described

  2. Home electrical system safety in Italy

    Energy Technology Data Exchange (ETDEWEB)

    Auditor,

    1990-06-01

    Italy, amongst the industrialized countries, has the highest mortality rate due to accidents associated with the improper use or maintenance of home electrical systems. The increasing use of domestic electrical appliances has raised the risk of accidents, especially in homes equipped with out-dated, low-capacity electrical plants and worn wiring. Within this context, this paper reports on the results of survey to establish the worthiness and type of electrical systems in use in a sample of 1,000 residential buildings. The paper then assesses the efficacy of recent normatives designed to increase the safety and efficiency of home electrical installations.

  3. Final Report to the National Energy Technology Laboratory on FY09-FY13 Cooperative Research with the Consortium for Electric Reliability Technology Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Vittal, Vijay [Arizona State Univ., Mesa, AZ (United States)

    2015-11-04

    The Consortium for Electric Reliability Technology Solutions (CERTS) was formed in 1999 in response to a call from U.S. Congress to restart a federal transmission reliability R&D program to address concerns about the reliability of the U.S. electric power grid. CERTS is a partnership between industry, universities, national laboratories, and government agencies. It researches, develops, and disseminates new methods, tools, and technologies to protect and enhance the reliability of the U.S. electric power system and the efficiency of competitive electricity markets. It is funded by the U.S. Department of Energy’s Office of Electricity Delivery and Energy Reliability (OE). This report provides an overview of PSERC and CERTS, of the overall objectives and scope of the research, a summary of the major research accomplishments, highlights of the work done under the various elements of the NETL cooperative agreement, and brief reports written by the PSERC researchers on their accomplishments, including research results, publications, and software tools.

  4. A design of electric power supply system for gamma irradiator ISG-500

    International Nuclear Information System (INIS)

    Harno Garnito; Enggar; Harjani; Ari Satmoko; Sutomo Budihaharjo

    2010-01-01

    Reliability of electrical power system in Irradiator system is absolutely necessary during the life cycle. Electrical energy is used as the main supporting element for both Irradiator operation of mechanical system, lighting, as well as for instrumentation and control systems. The reliability of electrical power system in the system can be achieved by paying attention Irradiator safety, simplicity of operation, ease of maintenance and possible future development. Distribution network of the most commonly used is the Radial network system, for the simple and in accordance with the criteria demanded by a distribution system. In addition to the network system, to get the reliability of electric power supply system is the selection of equipment/materials that meet the standards, and the installation of which provide facilities for maintenance and repairs. (author)

  5. Automating a spacecraft electrical power system using expert systems

    Science.gov (United States)

    Lollar, L. F.

    1991-01-01

    Since Skylab, Marshall Space Flight Center (MSFC) has recognized the need for large electrical power systems (EPS's) in upcoming Spacecraft. The operation of the spacecraft depends on the EPS. Therefore, it must be efficient, safe, and reliable. In 1978, as a consequence of having to supply a large number of EPS personnel to monitor and control Skylab, the Electrical power Branch of MSFC began the autonomously managed power system (AMPS) project. This project resulted in the assembly of a 25-kW high-voltage dc test facility and provided the means of getting man out of the loop as much as possible. AMPS includes several embedded controllers which allow a significant level of autonomous operation. More recently, the Electrical Division at MSFC has developed the space station module power management and distribution (SSM/PMAD) breadboard to investigate managing and distributing power in the Space Station Freedom habitation and laboratory modules. Again, the requirement for a high level of autonomy for the efficient operation over the lifetime of the station and for the benefits of enhanced safety has been demonstrated. This paper describes the two breadboards and the hierarchical approach to automation which was developed through these projects.

  6. Reliability issues of free-space communications systems and networks

    Science.gov (United States)

    Willebrand, Heinz A.

    2003-04-01

    Free space optics (FSO) is a high-speed point-to-point connectivity solution traditionally used in the enterprise campus networking market for building-to-building LAN connectivity. However, more recently some wire line and wireless carriers started to deploy FSO systems in their networks. The requirements on FSO system reliability, meaing both system availability and component reliability, are far more stringent in the carrier market when compared to the requirements in the enterprise market segment. This paper tries to outline some of the aspects that are important to ensure carrier class system reliability.

  7. Hybrid and Electric Advanced Vehicle Systems Simulation

    Science.gov (United States)

    Beach, R. F.; Hammond, R. A.; Mcgehee, R. K.

    1985-01-01

    Predefined components connected to represent wide variety of propulsion systems. Hybrid and Electric Advanced Vehicle System (HEAVY) computer program is flexible tool for evaluating performance and cost of electric and hybrid vehicle propulsion systems. Allows designer to quickly, conveniently, and economically predict performance of proposed drive train.

  8. Reliability analysis of an LCL tuned track segmented bi-directional inductive power transfer system

    DEFF Research Database (Denmark)

    Asif Iqbal, S. M.; Madawala, U. K.; Thrimawithana, D. J.

    2013-01-01

    Bi-directional Inductive Power Transfer (BDIPT) technique is suitable for renewable energy based applications such as electric vehicles (EVs), for the implementation of vehicle-to-grid (V2G) systems. Recently, more efforts have been made by researchers to improve both efficiency and reliability...... of renewable energy systems to further enhance their economical sustainability. This paper presents a comparative reliability study between a typical BDIPT system and an individually controlled segmented BDIPT system. Steady state thermal simulation results are provided for different output power levels...... for a 1.5 kW BDIPT system in a MATLAB/Simulink environment. Reliability parameters such as failure rate and mean time between failures (MTBF) are compared between the two systems. A nonlinear programming (NP) model is developed for optimizing charging schedule for a stationery EV. A case study of EV...

  9. Reliability analysis and initial requirements for FC systems and stacks

    Science.gov (United States)

    Åström, K.; Fontell, E.; Virtanen, S.

    In the year 2000 Wärtsilä Corporation started an R&D program to develop SOFC systems for CHP applications. The program aims to bring to the market highly efficient, clean and cost competitive fuel cell systems with rated power output in the range of 50-250 kW for distributed generation and marine applications. In the program Wärtsilä focuses on system integration and development. System reliability and availability are key issues determining the competitiveness of the SOFC technology. In Wärtsilä, methods have been implemented for analysing the system in respect to reliability and safety as well as for defining reliability requirements for system components. A fault tree representation is used as the basis for reliability prediction analysis. A dynamic simulation technique has been developed to allow for non-static properties in the fault tree logic modelling. Special emphasis has been placed on reliability analysis of the fuel cell stacks in the system. A method for assessing reliability and critical failure predictability requirements for fuel cell stacks in a system consisting of several stacks has been developed. The method is based on a qualitative model of the stack configuration where each stack can be in a functional, partially failed or critically failed state, each of the states having different failure rates and effects on the system behaviour. The main purpose of the method is to understand the effect of stack reliability, critical failure predictability and operating strategy on the system reliability and availability. An example configuration, consisting of 5 × 5 stacks (series of 5 sets of 5 parallel stacks) is analysed in respect to stack reliability requirements as a function of predictability of critical failures and Weibull shape factor of failure rate distributions.

  10. HEMP emergency planning and operating procedures for electric power systems. Power Systems Technology Program

    Energy Technology Data Exchange (ETDEWEB)

    Reddoch, T.W.; Markel, L.C. [Electrotek Concepts, Inc., Knoxville, TN (United States)

    1991-12-31

    Investigations of the impact of high-altitude electromagnetic pulse (HEMP) on electric power systems and electrical equipment have revealed that HEMP creates both misoperation and failures. These events result from both the early time E{sub 1} (steep-front pulse) component and the late time E{sub 3} (geomagnetic perturbations) component of HEMP. In this report a HEMP event is viewed in terms of its marginal impact over classical power system disturbances by considering the unique properties and consequences of HEMP. This report focuses on system-wide electrical component failures and their potential consequences from HEMP. In particular, the effectiveness of planning and operating procedures for electric systems is evaluated while under the influence of HEMP. This assessment relies on published data and characterizes utilities using the North American Electric Reliability Council`s regions and guidelines to model electric power system planning and operations. Key issues addressed by the report include how electric power systems are affected by HEMP and what actions electric utilities can initiate to reduce the consequences of HEMP. The report also reviews the salient features of earlier HEMP studies and projects, examines technology trends in the electric power industry which are affected by HEMP, characterizes the vulnerability of power systems to HEMP, and explores the capability of electric systems to recover from a HEMP event.

  11. Reliability analysis of the reactor protection system with fault diagnosis

    International Nuclear Information System (INIS)

    Lee, D.Y.; Han, J.B.; Lyou, J.

    2004-01-01

    The main function of a reactor protection system (RPS) is to maintain the reactor core integrity and reactor coolant system pressure boundary. The RPS consists of the 2-out-of-m redundant architecture to assure a reliable operation. The system reliability of the RPS is a very important factor for the probability safety assessment (PSA) evaluation in the nuclear field. To evaluate the system failure rate of the k-out-of-m redundant system is not so easy with the deterministic method. In this paper, the reliability analysis method using the binomial process is suggested to calculate the failure rate of the RPS system with a fault diagnosis function. The suggested method is compared with the result of the Markov process to verify the validation of the suggested method, and applied to the several kinds of RPS architectures for a comparative evaluation of the reliability. (orig.)

  12. Evolving Reliability and Maintainability Allocations for NASA Ground Systems

    Science.gov (United States)

    Munoz, Gisela; Toon, T.; Toon, J.; Conner, A.; Adams, T.; Miranda, D.

    2016-01-01

    This paper describes the methodology and value of modifying allocations to reliability and maintainability requirements for the NASA Ground Systems Development and Operations (GSDO) programs subsystems. As systems progressed through their design life cycle and hardware data became available, it became necessary to reexamine the previously derived allocations. This iterative process provided an opportunity for the reliability engineering team to reevaluate allocations as systems moved beyond their conceptual and preliminary design phases. These new allocations are based on updated designs and maintainability characteristics of the components. It was found that trade-offs in reliability and maintainability were essential to ensuring the integrity of the reliability and maintainability analysis. This paper discusses the results of reliability and maintainability reallocations made for the GSDO subsystems as the program nears the end of its design phase.

  13. Ultra-Reliable Communication in 5G Wireless Systems

    DEFF Research Database (Denmark)

    Popovski, Petar

    2014-01-01

    —Wireless 5G systems will not only be “4G, but faster”. One of the novel features discussed in relation to 5G is Ultra-Reliable Communication (URC), an operation mode not present in today’s wireless systems. URC refers to provision of certain level of communication service almost 100 % of the time....... Example URC applications include reliable cloud connectivity, critical connections for industrial automation and reliable wireless coordination among vehicles. This paper puts forward a systematic view on URC in 5G wireless systems. It starts by analyzing the fundamental mechanisms that constitute......-term URC (URC-S). The second dimension is represented by the type of reliability impairment that can affect the communication reliability in a given scenario. The main objective of this paper is to create the context for defining and solving the new engineering problems posed by URC in 5G....

  14. Calculation of Residual Electricity Mixes when Accounting for the EECS (European Electricity Certificate System — the Need for a Harmonised System

    Directory of Open Access Journals (Sweden)

    Ole Jørgen Hanssen

    2009-07-01

    Full Text Available According to the Electricity Directive, suppliers of electricity must disclose their electricity portfolio with regards to energy source and environmental impact. This paper gives some examples of disclosure systems and residual electricity mixes in Norway, Sweden and Finland, compared to an approach based on a common regional disclosure. Disclosures based on the E-TRACK standard are presented, as well as the variation in CO2 emissions from different residual mixes. The results from this study clearly show that there is a need for a harmonised, transparent and reliable system for the accounting of electricity disclosure in Europe.

  15. Reliability through markets in Ontario : submission by the Independent Electricity Market Operator to the Minister of Energy's Consultation Process

    International Nuclear Information System (INIS)

    2003-01-01

    For the past five years, Ontario has invested $1 billion to restructure and open its electricity market to competition. In recent months, and in response to residential consumers pricing concerns, the Independent Electricity Market Operator (IMO) transferred credits to local distribution companies allowing them to issue $75 rebates to all affected customers as of December 1, 2002, and to bill low-volume and other designated customers at a rate of 4.3 cents per kilowatt hour for the commodity portion of their bills. This report addresses the concern that price responsiveness will be lost for those parts of the market with fixed prices. It was noted that the reliability of the power system could be placed at risk if the range of customers with fixed prices is broadened. Fixed prices would also jeopardize the province's ability to attract new supply and enhance competition in the electricity sector. The IMO believes that price responsiveness in the wholesale market is crucial to the reliability of the electricity system and recommends that a plan for any additional fixed pricing should include a clearly defined phase-out over the period ending in 2006 as new supply comes on-line. The IMO emphasizes that the lack of price responsiveness to the market, particularly in peak energy demand periods, is equivalent to adding hundreds of MW to the load. The report presents lessons learned in other jurisdictions and highlights noteworthy considerations such as the market power mitigation agreement, improving competition, a phased-in approach, and demand side initiatives

  16. Challenges to China's transition to a low carbon electricity system

    International Nuclear Information System (INIS)

    Kahrl, Fredrich; Williams, Jim; Ding Jianhua; Hu Junfeng

    2011-01-01

    We examine the challenges to China's transition to a low carbon electricity system, in which renewable energy would play a significant role. China's electricity system currently lacks the flexibility in planning, operations, and pricing to respond to conflicting pressures from demand growth, rising costs, and environmental mandates in a way that simultaneously maintains reliability, decarbonizes the system, and keeps prices within acceptable bounds. Greater flexibility crucially requires the ability to more systematically and transparently manage and allocate costs. This will require re-orientating sector institutions still rooted in central planning, and strengthening independent regulation. Some of the necessary changes require fundamental political and legal reforms beyond the scope of energy policy. However, the system's flexibility can still be increased through the development of traditional planning and regulatory tools and approaches, such as an avoided cost basis for energy efficiency investments, more integrated planning to improve the coordination of generation, transmission, and demand-side investments, and a transparent ratemaking process. The judicious application of OECD electricity sector experience and skills can support these developments. - Research highlights: → China's electricity system currently lacks the flexibility to integrate renewables and reduce CO 2 emissions on a large scale at an acceptable cost and level of reliability. → The challenges to increased flexibility are more institutional than technological. → Chinese government agencies need new approaches to basic power system planning and ratemaking. → OECD countries can help address these challenges through the transfer of 'soft' technologies.

  17. Reserve valuation in electric power systems

    Science.gov (United States)

    Ruiz, Pablo Ariel

    Operational reliability is provided in part by scheduling capacity in excess of the load forecast. This reserve capacity balances the uncertain power demand with the supply in real time and provides for equipment outages. Traditionally, reserve scheduling has been ensured by enforcing reserve requirements in the operations planning. An alternate approach is to employ a stochastic formulation, which allows the explicit modeling of the sources of uncertainty. This thesis compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem. Numerical studies show that the unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach. These robust solutions are especially valuable in areas with a high proportion of wind power, as their built-in flexibility allows the dispatch of practically all the available wind power while minimizing the costs of operation. The scheduled reserve has an economic value since it reduces the outage costs. In several electricity markets, reserve demand functions have been implemented to take into account the value of reserve in the market clearing process. These often take the form of a step-down function at the reserve requirement level, and as such they may not appropriately represent the reserve value. The value of reserve is impacted by the reliability, dynamic and stochastic characteristics of system components, the system operation policies, and the economic aspects such as the risk preferences of the demand. In this thesis, these aspects are taken into account to approximate the reserve value and construct reserve demand functions. Illustrative examples show that the demand functions constructed have similarities with those implemented in some markets.

  18. Reliability model for common mode failures in redundant safety systems

    International Nuclear Information System (INIS)

    Fleming, K.N.

    1974-12-01

    A method is presented for computing the reliability of redundant safety systems, considering both independent and common mode type failures. The model developed for the computation is a simple extension of classical reliability theory. The feasibility of the method is demonstrated with the use of an example. The probability of failure of a typical diesel-generator emergency power system is computed based on data obtained from U. S. diesel-generator operating experience. The results are compared with reliability predictions based on the assumption that all failures are independent. The comparison shows a significant increase in the probability of redundant system failure, when common failure modes are considered. (U.S.)

  19. Techniques for increasing the reliability of accelerator control system electronics

    International Nuclear Information System (INIS)

    Utterback, J.

    1993-09-01

    As the physical size of modern accelerators becomes larger and larger, the number of required control system circuit boards increases, and the probability of one of those circuit boards failing while in service also increases. In order to do physics, the experimenters need the accelerator to provide beam reliably with as little down time as possible. With the advent of colliding beams physics, reliability becomes even more important due to the fact that a control system failure can cause the loss of painstakingly produced antiprotons. These facts prove the importance of keeping reliability in mind when designing and maintaining accelerator control system electronics

  20. The safety and reliability of the electricity transportation network, and the opening of markets

    International Nuclear Information System (INIS)

    Merlin, A.

    2003-01-01

    Following a decade in which the electricity sector was concerned by the opening of markets the world over, the year 2003 highlighted the challenges of secure supply and of the safety of electrical systems. Major incidents are nothing new throughout history, and occurred well before the trend towards opening the markets dot underway. However, it is necessary to verify that the rules for the organisation, clarification of responsibilities and regulation make it possible to control the growing complexity of interconnected systems related to opening the market up to competition. Faced with such situations, changes are necessary in Europe. Firstly, it is important to have the second European directive on the internal electricity market introduced everywhere, this directive providing common rules to be met by all key players to ensure greater safety within the electricity system, and strengthening the role of the electricity transport network manager, who is separate from the other players in the market. It is also necessary to draft a third directive, focusing on both security of supply and the operational safety of the European electricity system. (authors)

  1. Engineering systems reliability, safety, and maintenance an integrated approach

    CERN Document Server

    Dhillon, B S

    2017-01-01

    Today, engineering systems are an important element of the world economy and each year billions of dollars are spent to develop, manufacture, operate, and maintain various types of engineering systems around the globe. Many of these systems are highly sophisticated and contain millions of parts. For example, a Boeing jumbo 747 is made up of approximately 4.5 million parts including fasteners. Needless to say, reliability, safety, and maintenance of systems such as this have become more important than ever before.  Global competition and other factors are forcing manufacturers to produce highly reliable, safe, and maintainable engineering products. Therefore, there is a definite need for the reliability, safety, and maintenance professionals to work closely during design and other phases. Engineering Systems Reliability, Safety, and Maintenance: An Integrated Approach eliminates the need to consult many different and diverse sources in the hunt for the information required to design better engineering syste...

  2. Impact of nuclear fuel performance and reliability in a deregulated electricity market

    International Nuclear Information System (INIS)

    Barnoski, M.; Kaiser, B.

    1997-01-01

    US nuclear plants are now placing a great deal of importance on fuel performance and reliability because of their direct effect on a plant's capacity factor, availability, operating flexibility, outage duration, and worker exposure. This is reflected by utilities making fuel reliability a principal vendor evaluation criterion and making fuel performance an important bonus/penalty provision. Defect-free fuel, combined with ever improving design features, makes it possible for plants to operate at higher outputs while reducing operating and maintenance costs. Higher electrical output at lower cost is essential for US nuclear plants to meet the expected competition in a deregulated market. Through continued investment in manufacturing improvements and a vigilant, systematic design process, ABB's nuclear fuel has contributed to helping its nuclear utility customers reduce their cost of doing business. (author) 1 fig., 1 tab

  3. Influence of moisture and hydrogen purity of the reliability of powerful electric machines

    International Nuclear Information System (INIS)

    Vigovs'kij, O.V.; Khvalyin, D.Yi.; Mistets'kij, V.A.

    2017-01-01

    It is shown that today the turbo generators with hydrogen-water cooling system is most unreliable technical equipment of Ukrainian nuclear power plants. On the one hand, hydrogen has several advantages over other coolers; on the other hand, the presence of hydrogen in the turbo generators systems carries the danger of engine rooms of power plants. It is also shown that the water and oxygen are main hazardous impurities in hydrogen, and zone of generator shaft compaction is the most responsible zone with high concentration of water. From the analysis was found that increasing of hydrogen purity reduces the mechanical losses and the change in total losses depending on the hydrogen purity has a linear nature. For example, with an increase the hydrogen purity from 0,1203 to 0,09 the loss in turbo generator rotor can be reduced by nearly 500 kW, which is about 25 % at a pressure of 0,5 MPa. The possibility of using metal hydrides to ensure purity, purification and hydrogen sorption was looked. The most practical value is for such hydrides as LaNi5Hx, FeTiHx, ZrNiHx. The main advantage the metal hydrides method of purification is a significant reduction in the number of purification stages. It was shown that the use of a thermoelectric gas dryer will reduce the total consumption of technological gases, that are removed from nuclear power plants, by 2,3 - 2,4 times due to a decrease in 5,0 - 6,0 times their absolute humidity, and decrease by 5, 0 times the activity of gases due to an increase in their exposure time in the decrease activity installation. All this suggests that the creation a hydrogen humidity monitoring system in the exploited turbo generator will solve the problem of objective control of hydrogen purity with further computerization and accumulation the information. Using a drainage or purification system of hydrogen, reducing the temperature and humidity of the cooling gas, can increase the reliability of operation the turbo generators and significantly

  4. Nuclear power plants electrical retrofitting for cost effectiveness, reliability and operating efficiency

    International Nuclear Information System (INIS)

    Ciufu, L.; Popescu, M. O.

    2016-01-01

    In the context of continuous fast growing of the energy demand the current power plants retrofitting concept may represent an important step in the emission reduction, being able to offer in the same time a maximum operating efficiency. This desideratum can be obtained by implementing a rigorous energy management plan, based on an increased energy production capacity of non-pollutant electrical power plants and future-oriented frame on extending their lifetime operation. This management is focused on using state-of-art electronic, electrical and industrial control equipments, which can represent a real key factor. Thus, in this paper an analysis of the electrical system retrofitting is presented. As a part of this research the authors propose and simulate ambitious ways to upgrade actual control and command of the electrical operating systems, by promoting variable speed for large pumps and also computer software, as SCADA, for an intelligent control and monitoring of these studied processes. (authors)

  5. Foundations for a time reliability correlation system to quantify human reliability

    International Nuclear Information System (INIS)

    Dougherty, E.M. Jr.; Fragola, J.R.

    1988-01-01

    Time reliability correlations (TRCs) have been used in human reliability analysis (HRA) in conjunction with probabilistic risk assessment (PRA) to quantify post-initiator human failure events. The first TRCs were judgmental but recent data taken from simulators have provided evidence for development of a system of TRCs. This system has the equational form: t = tau R X tau U , where the first factor is the lognormally distributed random variable of successful response time, derived from the simulator data, and the second factor is a unitary lognormal random variable to account for uncertainty in the model. The first random variable is further factored into a median response time and a factor to account for the dominant type of behavior assumed to be involved in the response and a second factor to account for other influences on the reliability of the response

  6. Reliability of Structural Systems with Correlated Elements

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Sørensen, John Dalsgaard

    1982-01-01

    Calculation of the probability of failure of a system with correlation members is usually a difficult and time-consuming numerical problem. However, for some types of systems with equally correlated elements this calculation can be performed in a simple way. This has suggested two new methods bas...... on so-called average and equivalent correlation coefficients. By using these methods approximate values for the probability of failure can easily be calculated. The accuracy of these methods is illustrated with examples....

  7. Electric Aircraft Systems Technology Development

    Data.gov (United States)

    National Aeronautics and Space Administration — This project looks at multiple manned/unmanned full-scale/sub-scale flying research prototypes that will lead to the integration of electric propulsion technology on...

  8. Software reliability growth model for safety systems of nuclear reactor

    International Nuclear Information System (INIS)

    Thirugnana Murthy, D.; Murali, N.; Sridevi, T.; Satya Murty, S.A.V.; Velusamy, K.

    2014-01-01

    The demand for complex software systems has increased more rapidly than the ability to design, implement, test, and maintain them, and the reliability of software systems has become a major concern for our, modern society.Software failures have impaired several high visibility programs in space, telecommunications, defense and health industries. Besides the costs involved, it setback the projects. The ways of quantifying it and using it for improvement and control of the software development and maintenance process. This paper discusses need for systematic approaches for measuring and assuring software reliability which is a major share of project development resources. It covers the reliability models with the concern on 'Reliability Growth'. It includes data collection on reliability, statistical estimation and prediction, metrics and attributes of product architecture, design, software development, and the operational environment. Besides its use for operational decisions like deployment, it includes guiding software architecture, development, testing and verification and validation. (author)

  9. Demand participation in the restructured Electric Reliability Council of Texas market

    International Nuclear Information System (INIS)

    Zarnikau, Jay W.

    2010-01-01

    Does an electricity market which has been restructured to foster competition provide greater opportunities for demand response than a traditional regulated utility industry? The experiences of the restructured Electric Reliability Council of Texas (ERCOT) market over the past eight years provide some hope that it is possible to design a competitive market which will properly value and accommodate demand response. While the overall level of demand response in ERCOT is below the levels enjoyed prior to restructuring, there have nonetheless been some promising advances, including the integration of demand-side resources into competitive markets for ancillary services. ERCOT's experiences demonstrate that the degree of demand participation in a restructured market is highly sensitive to the market design. But even in a market which has been deregulated to a large degree, regulatory intervention and special demand-side programs may be needed in order to bolster demand response. (author)

  10. A reliability centered maintenance model applied to the auxiliary feedwater system of a nuclear power plant

    International Nuclear Information System (INIS)

    Araujo, Jefferson Borges

    1998-01-01

    The main objective of maintenance in a nuclear power plant is to assure that structures, systems and components will perform their design functions with reliability and availability in order to obtain a safety and economic electric power generation. Reliability Centered Maintenance (RCM) is a method of systematic review to develop or optimize Preventive Maintenance Programs. This study presents the objectives, concepts, organization and methods used in the development of RCM application to nuclear power plants. Some examples of this application are included, considering the Auxiliary Feedwater System of a generic two loops PWR nuclear power plant of Westinghouse design. (author)

  11. Daya Bay Nuclear Power Station equipment reliability management system innovation

    International Nuclear Information System (INIS)

    Gao Ligang; Wang Zongjun

    2006-01-01

    Daya Bay Nuclear Power Station has achieved good performance since its commercial operation in 1994. The equipment reliability management system that features Daya Bay characteristics has been established through constant technology introduction, digestion and innovation. It is also based on the success of operational system, equipment maintenance system and technical support system. The system lays a solid foundation for the long-term safe operation of power station. This article emphasizes on the innovation part of equipment reliability management system in Daya Bay. (authors)

  12. Criteriom of efficiency of thermometric systems with increased reliability

    International Nuclear Information System (INIS)

    Sal'nikov, N.L.; Filimonov, E.V.

    1995-01-01

    Problems on metrological reliability of thermometric systems, intended for temperature regime control at nuclear power facilities are discussed. Thermoelectrical converters and resistance thermoconverters are the most utilized sources of thermometric information at nuclear power plants. Two or more transducers are proposed to be unified in one measurement system in order to increase the accuracy of temperature measurements through obtaining surplus values. Two versions of thermometric systems organization are considered. The first system combined various-type temperature transducers whereas the second system consists of two similar-type transducers. It is established that thermometric systems with various-type transducers are characterized by higher metrological reliability. 3 refs.; 2 figs

  13. Approach to developing reliable space reactor power systems

    International Nuclear Information System (INIS)

    Mondt, J.F.; Shinbrot, C.H.

    1991-01-01

    The Space Reactor Power System Project is in the engineering development phase of a three-phase program. During Phase II, the Engineering Development Phase, the SP-100 Project has defined and is pursuing a new approach to developing reliable power systems. The approach to developing such a system during the early technology phase is described in this paper along with some preliminary examples to help explain the approach. Developing reliable components to meet space reactor power system requirements is based on a top down systems approach which includes a point design based on a detailed technical specification of a 100 kW power system

  14. Reliability of thermal-hydraulic passive safety systems

    International Nuclear Information System (INIS)

    D'Auria, F.; Araneo, D.; Pierro, F.; Galassi, G.

    2014-01-01

    The scholar will be informed of reliability concepts applied to passive system adopted for nuclear reactors. Namely, for classical components and systems the failure concept is associated with malfunction of breaking of hardware. In the case of passive systems the failure is associated with phenomena. A method for studying the reliability of passive systems is discussed and is applied. The paper deals with the description of the REPAS (Reliability Evaluation of Passive Safety System) methodology developed by University of Pisa (UNIPI) and with results from its application. The general objective of the REPAS methodology is to characterize the performance of a passive system in order to increase the confidence toward its operation and to compare the performances of active and passive systems and the performances of different passive systems

  15. Application of fault tree analysis for customer reliability assessment of a distribution power system

    International Nuclear Information System (INIS)

    Abdul Rahman, Fariz; Varuttamaseni, Athi; Kintner-Meyer, Michael; Lee, John C.

    2013-01-01

    A new method is developed for predicting customer reliability of a distribution power system using the fault tree approach with customer weighted values of component failure frequencies and downtimes. Conventional customer reliability prediction of the electric grid employs the system average (SA) component failure frequency and downtime that are weighted by only the quantity of the components in the system. These SA parameters are then used to calculate the reliability and availability of components in the system, and eventually to find the effect on customer reliability. Although this approach is intuitive, information is lost regarding customer disturbance experiences when customer information is not utilized in the SA parameter calculations, contributing to inaccuracies when predicting customer reliability indices in our study. Hence our new approach directly incorporates customer disturbance information in component failure frequency and downtime calculations by weighting these parameters with information of customer interruptions. This customer weighted (CW) approach significantly improves the prediction of customer reliability indices when applied to our reliability model with fault tree and two-state Markov chain formulations. Our method has been successfully applied to an actual distribution power system that serves over 2.1 million customers. Our results show an improved benchmarking performance on the system average interruption frequency index (SAIFI) by 26% between the SA-based and CW-based reliability calculations. - Highlights: ► We model the reliability of a power system with fault tree and two-state Markov chain. ► We propose using customer weighted component failure frequencies and downtimes. ► Results show customer weighted values perform superior to component average values. ► This method successfully incorporates customer disturbance information into the model.

  16. Efficiency criteria for high reliability measured system structures

    International Nuclear Information System (INIS)

    Sal'nikov, N.L.

    2012-01-01

    The procedures of structural redundancy are usually used to develop high reliability measured systems. To estimate efficiency of such structures the criteria to compare different systems has been developed. So it is possible to develop more exact system by inspection of redundant system data unit stochastic characteristics in accordance with the developed criteria [ru

  17. Software reliability and safety in nuclear reactor protection systems

    International Nuclear Information System (INIS)

    Lawrence, J.D.

    1993-11-01

    Planning the development, use and regulation of computer systems in nuclear reactor protection systems in such a way as to enhance reliability and safety is a complex issue. This report is one of a series of reports from the Computer Safety and Reliability Group, Lawrence Livermore that investigates different aspects of computer software in reactor National Laboratory, that investigates different aspects of computer software in reactor protection systems. There are two central themes in the report, First, software considerations cannot be fully understood in isolation from computer hardware and application considerations. Second, the process of engineering reliability and safety into a computer system requires activities to be carried out throughout the software life cycle. The report discusses the many activities that can be carried out during the software life cycle to improve the safety and reliability of the resulting product. The viewpoint is primarily that of the assessor, or auditor

  18. Automation of testing the metrological reliability of nondestructive control systems

    International Nuclear Information System (INIS)

    Zhukov, Yu.A.; Isakov, V.B.; Karlov, Yu.K.; Kovalevskij, Yu.A.

    1987-01-01

    Opportunities of microcomputers are used to solve the problem of testing control-measuring systems. Besides the main program the program of data processing when characterizing the nondestructive control systems is written in the microcomputer. The program includes two modules. The first module contains tests-programs, by which accuracy of functional elements of the microcomputer and interface elements with issuing a message to the operator on readiness of the elements for operation and failure of a certain element are determined. The second module includes: calculational programs when determining metrological reliability of measuring channel reliability, a calculational subprogram for random statistical measuring error, time instability and ''dead time''. Automation of testing metrological reliability of the nondestructive control systems increases reliability of determining metrological parameters and reduces time of system testing

  19. Software reliability and safety in nuclear reactor protection systems

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, J.D. [Lawrence Livermore National Lab., CA (United States)

    1993-11-01

    Planning the development, use and regulation of computer systems in nuclear reactor protection systems in such a way as to enhance reliability and safety is a complex issue. This report is one of a series of reports from the Computer Safety and Reliability Group, Lawrence Livermore that investigates different aspects of computer software in reactor National Laboratory, that investigates different aspects of computer software in reactor protection systems. There are two central themes in the report, First, software considerations cannot be fully understood in isolation from computer hardware and application considerations. Second, the process of engineering reliability and safety into a computer system requires activities to be carried out throughout the software life cycle. The report discusses the many activities that can be carried out during the software life cycle to improve the safety and reliability of the resulting product. The viewpoint is primarily that of the assessor, or auditor.

  20. Reliability analysis of digital safety systems at nuclear power plants

    International Nuclear Information System (INIS)

    Sopira Vladimir; Kovacs, Zoltan

    2015-01-01

    Reliability analysis of digital reactor protection systems built on the basis of TELEPERM XS is described, and experience gained by the Slovak RELKO company during the past 20 years in this domain is highlighted. (orig.)

  1. Can We Make Operating Systems Reliable and Secure?

    NARCIS (Netherlands)

    Tanenbaum, A.S.; Herder, J.N.; Bos, H.J.

    2006-01-01

    Microkernels--long discarded as unacceptable because of their lower performance compared with monolithic kernels--might be making a comeback in operating systems due to their potentially higher reliability, which many researchers now regard as more important than performance.

  2. Quantifiable and Reliable Structural Health Management Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Major concerns for implementing a practical built-in structural health monitoring system are prediction accuracy and data reliability. It is proposed to develop...

  3. Electrical energy market management in deregulated power system

    International Nuclear Information System (INIS)

    Abady, A. F.; Niknam, T.

    2003-01-01

    For many decades, vertically integrated electric utilities monopolized the way they control, sell and distribute electricity to customers in their service territories. In this monopoly, each utility managed three main components of the system: generation, transmission and distribution. Analogous to perceived competitions in airline, communication and natural gas industries which demonstrated that vertically integrated monopolies could not provide services as efficiently as competitive firms, the electric power industry plans to improve its efficiency by providing a more reliable energy at least cost to customers. A competition is guaranteed by establishing a restructured environment in which customers could choose to buy from different suppliers and change suppliers as they wish in order to pay market base rates. This paper is dealing with progressive approach of restructuring in power and introduce ISO, its functions and model of electrical energy markets

  4. Some aspects of the interaction between systems- and structural reliability

    International Nuclear Information System (INIS)

    Schueller, G.K.; Schmitt, W.

    1979-01-01

    The purpose of this paper is to study the interaction between systems- and structural reliability analysis with reference to the design of structural components of LWR. Presently the evaluation of systems reliability is carried out apart from structural reliability analysis. Moreover, two basically different methodologies are used for analysis. While in systems analysis the simplified binary approach is still generally accepted, in structural reliability one has to resort to more sophisticated procedures to obtain realistic results. The interactive effect may be illustrated as follows: For example, the integrity of the primary circuit interacts with the integrity of the containment structure. This means that the probability of occurrence of the pipe rupture which may cause a LOCA and consequently leads to a build-up of temperature and pressure within the containment affects directly its structural reliability. The piping system, particularly the primary piping, in turn interacts with the protective system, which is part of the safety system. This piping structure is also subjected to various operational loading conditions. In a numerical example dealing with leakage probabilities of pipes it is shown how methods of structural reliability may be used to gain more insight in the estimation of failure rates of system components. (orig.)

  5. Computer Model to Estimate Reliability Engineering for Air Conditioning Systems

    International Nuclear Information System (INIS)

    Afrah Al-Bossly, A.; El-Berry, A.; El-Berry, A.

    2012-01-01

    Reliability engineering is used to predict the performance and optimize design and maintenance of air conditioning systems. Air conditioning systems are expose to a number of failures. The failures of an air conditioner such as turn on, loss of air conditioner cooling capacity, reduced air conditioning output temperatures, loss of cool air supply and loss of air flow entirely can be due to a variety of problems with one or more components of an air conditioner or air conditioning system. Forecasting for system failure rates are very important for maintenance. This paper focused on the reliability of the air conditioning systems. Statistical distributions that were commonly applied in reliability settings: the standard (2 parameter) Weibull and Gamma distributions. After distributions parameters had been estimated, reliability estimations and predictions were used for evaluations. To evaluate good operating condition in a building, the reliability of the air conditioning system that supplies conditioned air to the several The company's departments. This air conditioning system is divided into two, namely the main chilled water system and the ten air handling systems that serves the ten departments. In a chilled-water system the air conditioner cools water down to 40-45 degree F (4-7 degree C). The chilled water is distributed throughout the building in a piping system and connected to air condition cooling units wherever needed. Data analysis has been done with support a computer aided reliability software, this is due to the Weibull and Gamma distributions indicated that the reliability for the systems equal to 86.012% and 77.7% respectively. A comparison between the two important families of distribution functions, namely, the Weibull and Gamma families was studied. It was found that Weibull method performed for decision making.

  6. Distribution system reliability evaluation using credibility theory

    African Journals Online (AJOL)

    Xufeng Xu, Joydeep Mitra

    have found that credibility theory, which broadens the scope of fuzzy set theory, is an effective tool for representing fuzzy events, and have developed a theoretical .... Based on the status of switches, the distribution system can be divided into multiple SPSS, which are connected with tie switches. For example, SPSS.

  7. Reliability analysis and updating of deteriorating systems with subset simulation

    DEFF Research Database (Denmark)

    Schneider, Ronald; Thöns, Sebastian; Straub, Daniel

    2017-01-01

    An efficient approach to reliability analysis of deteriorating structural systems is presented, which considers stochastic dependence among element deterioration. Information on a deteriorating structure obtained through inspection or monitoring is included in the reliability assessment through B...... is an efficient and robust sampling-based algorithm suitable for such analyses. The approach is demonstrated in two case studies considering a steel frame structure and a Daniels system subjected to high-cycle fatigue....

  8. Use of COMCAN III in system design and reliability analysis

    International Nuclear Information System (INIS)

    Rasmuson, D.M.; Shepherd, J.C.; Marshall, N.H.; Fitch, L.R.

    1982-03-01

    This manual describes the COMCAN III computer program and its use. COMCAN III is a tool that can be used by the reliability analyst performing a probabilistic risk assessment or by the designer of a system desiring improved performance and efficiency. COMCAN III can be used to determine minimal cut sets of a fault tree, to calculate system reliability characteristics, and to perform qualitative common cause failure analysis

  9. Distributed Electrical Energy Systems: Needs, Concepts, Approaches and Vision

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingchen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhang, Jun [University of Denver; Gao, Wenzhong [University of Denver; Zheng, Xinhu [University of Minnesota; Yang, Liuqing [Colorado State University; Hao, Jun [University of Denver; Dai, Xiaoxiao [University of Denver

    2017-09-01

    Intelligent distributed electrical energy systems (IDEES) are featured by vast system components, diversifled component types, and difficulties in operation and management, which results in that the traditional centralized power system management approach no longer flts the operation. Thus, it is believed that the blockchain technology is one of the important feasible technical paths for building future large-scale distributed electrical energy systems. An IDEES is inherently with both social and technical characteristics, as a result, a distributed electrical energy system needs to be divided into multiple layers, and at each layer, a blockchain is utilized to model and manage its logic and physical functionalities. The blockchains at difierent layers coordinate with each other and achieve successful operation of the IDEES. Speciflcally, the multi-layer blockchains, named 'blockchain group', consist of distributed data access and service blockchain, intelligent property management blockchain, power system analysis blockchain, intelligent contract operation blockchain, and intelligent electricity trading blockchain. It is expected that the blockchain group can be self-organized into a complex, autonomous and distributed IDEES. In this complex system, frequent and in-depth interactions and computing will derive intelligence, and it is expected that such intelligence can bring stable, reliable and efficient electrical energy production, transmission and consumption.

  10. Advanced Reconnaissance System Component Reliability Study

    Science.gov (United States)

    1956-07-31

    dielectrics. Gaseous dielectrics such as sulphur hexafluoride and ’ fluorocarbons at two to three atmospheres. Fluorinated liquid dielectrics. 3) The...limits. (2) determine compatibility with varnish treatments, (3) compatibility in a complete insulation system. Mechanical and thermal limits of...of a varnish to have good • adhersion, provide an element of flexibility and be chemically compatible with’the wire it is impregnating.. Factors of

  11. Electric power system applications of optimization

    CERN Document Server

    Momoh, James A

    2008-01-01

    Introduction Structure of a Generic Electric Power System  Power System Models  Power System Control Power System Security Assessment  Power System Optimization as a Function of Time  Review of Optimization Techniques Applicable to Power Systems Electric Power System Models  Complex Power Concepts Three-Phase Systems Per Unit Representation  Synchronous Machine Modeling Reactive Capability Limits Prime Movers and Governing Systems  Automatic Gain Control Transmission Subsystems  Y-Bus Incorporating the Transformer Effect  Load Models  Available Transfer Capability  Illustrative Examples  Power

  12. Operator adaptation to changes in system reliability under adaptable automation.

    Science.gov (United States)

    Chavaillaz, Alain; Sauer, Juergen

    2017-09-01

    This experiment examined how operators coped with a change in system reliability between training and testing. Forty participants were trained for 3 h on a complex process control simulation modelling six levels of automation (LOA). In training, participants either experienced a high- (100%) or low-reliability system (50%). The impact of training experience on operator behaviour was examined during a 2.5 h testing session, in which participants either experienced a high- (100%) or low-reliability system (60%). The results showed that most operators did not often switch between LOA. Most chose an LOA that relieved them of most tasks but maintained their decision authority. Training experience did not have a strong impact on the outcome measures (e.g. performance, complacency). Low system reliability led to decreased performance and self-confidence. Furthermore, complacency was observed under high system reliability. Overall, the findings suggest benefits of adaptable automation because it accommodates different operator preferences for LOA. Practitioner Summary: The present research shows that operators can adapt to changes in system reliability between training and testing sessions. Furthermore, it provides evidence that each operator has his/her preferred automation level. Since this preference varies strongly between operators, adaptable automation seems to be suitable to accommodate these large differences.

  13. Final Report for the Virtual Reliability Realization System LDRD

    Energy Technology Data Exchange (ETDEWEB)

    DELLIN, THEODORE A.; HENDERSON, CHRISTOPHER L.; O' TOOLE, EDWARD J.

    2000-12-01

    Current approaches to reliability are not adequate to keep pace with the need for faster, better and cheaper products and systems. This is especially true in high consequence of failure applications. The original proposal for the LDRD was to look at this challenge and see if there was a new paradigm that could make reliability predictions, along with a quantitative estimate of the risk in that prediction, in a way that was faster, better and cheaper. Such an approach would be based on the underlying science models that are the backbone of reliability predictions. The new paradigm would be implemented in two software tools: the Virtual Reliability Realization System (VRRS) and the Reliability Expert System (REX). The three-year LDRD was funded at a reduced level for the first year ($120K vs. $250K) and not renewed. Because of the reduced funding, we concentrated on the initial development of the expertise system. We developed an interactive semiconductor calculation tool needed for reliability analyses. We also were able to generate a basic functional system using Microsoft Siteserver Commerce Edition and Microsoft Sequel Server. The base system has the capability to store Office documents from multiple authors, and has the ability to track and charge for usage. The full outline of the knowledge model has been incorporated as well as examples of various types of content.

  14. Design for reliability information and computer-based systems

    CERN Document Server

    Bauer, Eric

    2010-01-01

    "System reliability, availability and robustness are often not well understood by system architects, engineers and developers. They often don't understand what drives customer's availability expectations, how to frame verifiable availability/robustness requirements, how to manage and budget availability/robustness, how to methodically architect and design systems that meet robustness requirements, and so on. The book takes a very pragmatic approach of framing reliability and robustness as a functional aspect of a system so that architects, designers, developers and testers can address it as a concrete, functional attribute of a system, rather than an abstract, non-functional notion"--Provided by publisher.

  15. Influence Of Inspection Intervals On Mechanical System Reliability

    International Nuclear Information System (INIS)

    Zilberman, B.

    1998-01-01

    In this paper a methodology of reliability analysis of mechanical systems with latent failures is described. Reliability analysis of such systems must include appropriate usage of check intervals for latent failure detection. The methodology suggests, that based on system logic the analyst decides at the beginning if a system can fail actively or latently and propagates this approach through all system levels. All inspections are assumed to be perfect (all failures are detected and repaired and no new failures are introduced as a result of the maintenance). Additional assumptions are that mission time is much smaller, than check intervals and all components have constant failure rates. Analytical expressions for reliability calculates are provided, based on fault tree and Markov modeling techniques (for two and three redundant systems with inspection intervals). The proposed methodology yields more accurate results than are obtained by not using check intervals or using half check interval times. The conventional analysis assuming that at the beginning of each mission system is as new, give an optimistic prediction of system reliability. Some examples of reliability calculations of mechanical systems with latent failures and establishing optimum check intervals are provided

  16. An approach for assessing ALWR passive safety system reliability

    International Nuclear Information System (INIS)

    Hake, T.M.

    1991-01-01

    Many of the advanced light water reactor (ALWR) concepts proposed for the next generation of nuclear power plants rely on passive rather than active systems to perform safety functions. Despite the reduced redundancy of the passive systems as compared to active systems in current plants, the assertion is that the overall safety of the plant is enhanced due to the much higher expected reliability of the passive systems. In order to investigate this assertion, a study is being conducted at Sandia National Laboratories to evaluate the reliability of ALWR passive safety features in the context of probabilistic risk assessment (PRA). The purpose of this paper is to provide a brief overview of the approach to this study. The quantification of passive system reliability is not as straightforward as for active systems, due to the lack of operating experience, and to the greater uncertainty in the governing physical phenomena. Thus, the adequacy of current methods for evaluating system reliability must be assessed, and alternatives proposed if necessary. For this study, the Westinghouse Advanced Passive 600 MWe reactor (AP600) was chosen as the advanced reactor for analysis, because of the availability of AP600 design information. This study compares the reliability of AP600 emergency cooling system with that of corresponding systems in a current generation reactor

  17. SOFC Systems with Improved Reliability and Endurance

    Energy Technology Data Exchange (ETDEWEB)

    Ghezel-Ayagh, Hossein [Fuelcell Energy, Incorporated, Danbury, CT (United States)

    2015-12-31

    The overall goal of this U.S. Department of Energy (DOE) sponsored project was the development of Solid Oxide Fuel Cell (SOFC) technology suitable for ultra-efficient central power generation systems utilizing coal and natural gas fuels and featuring greater than 90% carbon dioxide capture. The specific technical objective of this project was to demonstrate, via analyses and testing, progress towards adequate stack life (≥ 4 years) and stack performance stability (degradation rate ≤ 0.2% per 1000 hours) in a low-cost SOFC stack design. This final technical report summarizes the progress made during the project period of 27 months. Significant progress was made in the areas of cell and stack technology development, stack module development, sub-scale module tests, and Proof-of-Concept Module unit design, fabrication and testing. The work focused on cell and stack materials and designs, balance-of-plant improvements, and performance evaluation covering operating conditions and fuel compositions anticipated for commercially-deployed systems. In support of performance evaluation under commercial conditions, this work included the design, fabrication, siting, commissioning, and operation of a ≥ 50 kWe proof-of-concept module (PCM) power plant, based upon SOFC cell and stack technology developed to date by FuelCell Energy, Inc. (FCE) under the Office of Fossil Energy’s Solid Oxide Fuel Cells program. The PCM system was operated for at least 1000 hours on natural gas fuel at FCE’s facility. The factory cost of the SOFC stack was estimated to be at or below the DOE’s high-volume production cost target (2011 $).

  18. Joint interval reliability for Markov systems with an application in transmission line reliability

    International Nuclear Information System (INIS)

    Csenki, Attila

    2007-01-01

    We consider Markov reliability models whose finite state space is partitioned into the set of up states U and the set of down states D . Given a collection of k disjoint time intervals I l =[t l ,t l +x l ], l=1,...,k, the joint interval reliability is defined as the probability of the system being in U for all time instances in I 1 union ... union I k . A closed form expression is derived here for the joint interval reliability for this class of models. The result is applied to power transmission lines in a two-state fluctuating environment. We use the Linux versions of the free packages Maxima and Scilab in our implementation for symbolic and numerical work, respectively

  19. Joint interval reliability for Markov systems with an application in transmission line reliability

    Energy Technology Data Exchange (ETDEWEB)

    Csenki, Attila [School of Computing and Mathematics, University of Bradford, Bradford, West Yorkshire, BD7 1DP (United Kingdom)]. E-mail: a.csenki@bradford.ac.uk

    2007-06-15

    We consider Markov reliability models whose finite state space is partitioned into the set of up states {sub U} and the set of down states {sub D}. Given a collection of k disjoint time intervals I{sub l}=[t{sub l},t{sub l}+x{sub l}], l=1,...,k, the joint interval reliability is defined as the probability of the system being in {sub U} for all time instances in I{sub 1} union ... union I{sub k}. A closed form expression is derived here for the joint interval reliability for this class of models. The result is applied to power transmission lines in a two-state fluctuating environment. We use the Linux versions of the free packages Maxima and Scilab in our implementation for symbolic and numerical work, respectively.

  20. A novel reliability evaluation method for large engineering systems

    Directory of Open Access Journals (Sweden)

    Reda Farag

    2016-06-01

    Full Text Available A novel reliability evaluation method for large nonlinear engineering systems excited by dynamic loading applied in time domain is presented. For this class of problems, the performance functions are expected to be function of time and implicit in nature. Available first- or second-order reliability method (FORM/SORM will be challenging to estimate reliability of such systems. Because of its inefficiency, the classical Monte Carlo simulation (MCS method also cannot be used for large nonlinear dynamic systems. In the proposed approach, only tens instead of hundreds or thousands of deterministic evaluations at intelligently selected points are used to extract the reliability information. A hybrid approach, consisting of the stochastic finite element method (SFEM developed by the author and his research team using FORM, response surface method (RSM, an interpolation scheme, and advanced factorial schemes, is proposed. The method is clarified with the help of several numerical examples.

  1. 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.

  2. Reliability-oriented energy storage sizing in wind power systems

    DEFF Research Database (Denmark)

    Qin, Zian; Liserre, Marco; Blaabjerg, Frede

    2014-01-01

    Energy storage can be used to suppress the power fluctuations in wind power systems, and thereby reduce the thermal excursion and improve the reliability. Since the cost of the energy storage in large power application is high, it is crucial to have a better understanding of the relationship...... between the size of the energy storage and the reliability benefit it can generate. Therefore, a reliability-oriented energy storage sizing approach is proposed for the wind power systems, where the power, energy, cost and the control strategy of the energy storage are all taken into account....... With the proposed approach, the computational effort is reduced and the impact of the energy storage system on the reliability of the wind power converter can be quantified....

  3. Reliability analysis framework for computer-assisted medical decision systems

    International Nuclear Information System (INIS)

    Habas, Piotr A.; Zurada, Jacek M.; Elmaghraby, Adel S.; Tourassi, Georgia D.

    2007-01-01

    We present a technique that enhances computer-assisted decision (CAD) systems with the ability to assess the reliability of each individual decision they make. Reliability assessment is achieved by measuring the accuracy of a CAD system with known cases similar to the one in question. The proposed technique analyzes the feature space neighborhood of the query case to dynamically select an input-dependent set of known cases relevant to the query. This set is used to assess the local (query-specific) accuracy of the CAD system. The estimated local accuracy is utilized as a reliability measure of the CAD response to the query case. The underlying hypothesis of the study is that CAD decisions with higher reliability are more accurate. The above hypothesis was tested using a mammographic database of 1337 regions of interest (ROIs) with biopsy-proven ground truth (681 with masses, 656 with normal parenchyma). Three types of decision models, (i) a back-propagation neural network (BPNN), (ii) a generalized regression neural network (GRNN), and (iii) a support vector machine (SVM), were developed to detect masses based on eight morphological features automatically extracted from each ROI. The performance of all decision models was evaluated using the Receiver Operating Characteristic (ROC) analysis. The study showed that the proposed reliability measure is a strong predictor of the CAD system's case-specific accuracy. Specifically, the ROC area index for CAD predictions with high reliability was significantly better than for those with low reliability values. This result was consistent across all decision models investigated in the study. The proposed case-specific reliability analysis technique could be used to alert the CAD user when an opinion that is unlikely to be reliable is offered. The technique can be easily deployed in the clinical environment because it is applicable with a wide range of classifiers regardless of their structure and it requires neither additional

  4. Reliable Software Development for Machine Protection Systems

    CERN Document Server

    Anderson, D; Dragu, M; Fuchsberger, K; Garnier, JC; Gorzawski, AA; Koza, M; Krol, K; Misiowiec, K; Stamos, K; Zerlauth, M

    2014-01-01

    The Controls software for the Large Hadron Collider (LHC) at CERN, with more than 150 millions lines of code, resides amongst the largest known code bases in the world1. Industry has been applying Agile software engineering techniques for more than two decades now, and the advantages of these techniques can no longer be ignored to manage the code base for large projects within the accelerator community. Furthermore, CERN is a particular environment due to the high personnel turnover and manpower limitations, where applying Agile processes can improve both, the codebase management as well as its quality. This paper presents the successful application of the Agile software development process Scrum for machine protection systems at CERN, the quality standards and infrastructure introduced together with the Agile process as well as the challenges encountered to adapt it to the CERN environment.

  5. Software Reliability Issues Concerning Large and Safety Critical Software Systems

    Science.gov (United States)

    Kamel, Khaled; Brown, Barbara

    1996-01-01

    This research was undertaken to provide NASA with a survey of state-of-the-art techniques using in industrial and academia to provide safe, reliable, and maintainable software to drive large systems. Such systems must match the complexity and strict safety requirements of NASA's shuttle system. In particular, the Launch Processing System (LPS) is being considered for replacement. The LPS is responsible for monitoring and commanding the shuttle during test, repair, and launch phases. NASA built this system in the 1970's using mostly hardware techniques to provide for increased reliability, but it did so often using custom-built equipment, which has not been able to keep up with current technologies. This report surveys the major techniques used in industry and academia to ensure reliability in large and critical computer systems.

  6. Rural Electricity and Isolated Systems

    International Nuclear Information System (INIS)

    Ruiz, Otto; Solorzano, Benjamin

    2000-01-01

    The paper describes the impact of the cost of investment, operation and trading of rural electricity and discuss cost-benefit analysis. This evaluation covers a three different periods: before 1990, the period 1990-1996 and 1997-1999. Also the trends of demand and supply of energy are presented

  7. Models of Information Security Highly Reliable Computing Systems

    Directory of Open Access Journals (Sweden)

    Vsevolod Ozirisovich Chukanov

    2016-03-01

    Full Text Available Methods of the combined reservation are considered. The models of reliability of systems considering parameters of restoration and prevention of blocks of system are described. Ratios for average quantity prevention and an availability quotient of blocks of system are given.

  8. Reliability assessment of complex electromechanical systems under epistemic uncertainty

    International Nuclear Information System (INIS)

    Mi, Jinhua; Li, Yan-Feng; Yang, Yuan-Jian; Peng, Weiwen; Huang, Hong-Zhong

    2016-01-01

    The appearance of macro-engineering and mega-project have led to the increasing complexity of modern electromechanical systems (EMSs). The complexity of the system structure and failure mechanism makes it more difficult for reliability assessment of these systems. Uncertainty, dynamic and nonlinearity characteristics always exist in engineering systems due to the complexity introduced by the changing environments, lack of data and random interference. This paper presents a comprehensive study on the reliability assessment of complex systems. In view of the dynamic characteristics within the system, it makes use of the advantages of the dynamic fault tree (DFT) for characterizing system behaviors. The lifetime of system units can be expressed as bounded closed intervals by incorporating field failures, test data and design expertize. Then the coefficient of variation (COV) method is employed to estimate the parameters of life distributions. An extended probability-box (P-Box) is proposed to convey the present of epistemic uncertainty induced by the incomplete information about the data. By mapping the DFT into an equivalent Bayesian network (BN), relevant reliability parameters and indexes have been calculated. Furthermore, the Monte Carlo (MC) simulation method is utilized to compute the DFT model with consideration of system replacement policy. The results show that this integrated approach is more flexible and effective for assessing the reliability of complex dynamic systems. - Highlights: • A comprehensive study on the reliability assessment of complex system is presented. • An extended probability-box is proposed to convey the present of epistemic uncertainty. • The dynamic fault tree model is built. • Bayesian network and Monte Carlo simulation methods are used. • The reliability assessment of a complex electromechanical system is performed.

  9. On the complex analysis of the reliability, safety, and economic efficiency of atomic electric power stations

    International Nuclear Information System (INIS)

    Emel'yanov, I.Ya.; Klemin, A.I.; Polyakov, E.F.

    1977-01-01

    The problem is posed of effectively increasing the engineering performance of nuclear electric power stations (APS). The principal components of the engineering performance of modern large APS are considered: economic efficiency, radiation safety, reliability, and their interrelationship. A nomenclature is proposed for the quantitative indices which most completely characterize the enumerated properties and are convenient for the analysis of the engineering performance. The urgent problem of developing a methodology for the complex analysis and optimization of the principal performance components is considered; this methodology is designed to increase the efficiency of the work on high-performance competitive APS. The principle of complex optimization of the reliability, safety, and economic-efficiency indices is formulated; specific recommendations are made for the practical realization of this principle. The structure of the complex quantiative analysis of the enumerated performance components is given. The urgency and promise of the complex approach to solving the problem of APS optimization is demonstrated, i.e., the solution of the problem of creating optimally reliable, fairly safe, and maximally economically efficient stations

  10. Expansion planning for electrical generating systems

    International Nuclear Information System (INIS)

    1984-01-01

    The guidebook outlines the general principles of electric power system planning in the context of energy and economic planning in general. It describes the complexities of electric system expansion planning that are due to the time dependence of the problem and the interrelation between the main components of the electric system (generation, transmission and distribution). Load forecasting methods are discussed and the principal models currently used for electric system expansion planning presented. Technical and economic information on power plants is given. Constraints imposed on power system planning by plant characteristics (particularly nuclear power plants) are discussed, as well as factors such as transmission system development, environmental considerations, availability of manpower and financial resources that may affect the proposed plan. A bibliography supplements the references that appear in each chapter, and a comprehensive glossary defines terms used in the guidebook

  11. Sensitivity analysis in electric system expansion planning study using DECADES

    International Nuclear Information System (INIS)

    Perez Martin, D.; Lopez Lopez, I.

    1998-01-01

    To cover the increasing electricity demand as a key economic and social factor of development, it is necessary to have adequate expansion police. The delay in installation of certain capabilities produces electricity deficit. In other hand, construction of oversized capacities generates excessive costs. Therefore it is important to acquire or develop adequate methodologies according to the country specific conditions to carry out electric expansion planning studies. The goal is to chose optimal solutions in order to reach sustainable development using owns energy resources and preserving the environment. In the paper the Decades methodology is used for electricity system expansion planning. Premises and main assumptions for the calculations are presented. Some electric system expansion cases are evaluated. We also present the results of a sensibility study varying the discount rate, loss of load probability energy not served cost, fuel availability and fuel and investment costs. The reliability criteria currently not used in Cuban electric system are evaluated. We discuss the results and display the conclusions and recommendations

  12. Incorporating Cyber Layer Failures in Composite Power System Reliability Evaluations

    Directory of Open Access Journals (Sweden)

    Yuqi Han

    2015-08-01

    Full Text Available This paper proposes a novel approach to analyze the impacts of cyber layer failures (i.e., protection failures and monitoring failures on the reliability evaluation of composite power systems. The reliability and availability of the cyber layer and its protection and monitoring functions with various topologies are derived based on a reliability block diagram method. The availability of the physical layer components are modified via a multi-state Markov chain model, in which the component protection and monitoring strategies, as well as the cyber layer topology, are simultaneously considered. Reliability indices of composite power systems are calculated through non-sequential Monte-Carlo simulation. Case studies demonstrate that operational reliability downgrades in cyber layer function failure situations. Moreover, protection function failures have more significant impact on the downgraded reliability than monitoring function failures do, and the reliability indices are especially sensitive to the change of the cyber layer function availability in the range from 0.95 to 1.

  13. A Survey of Wireless Communications for the Electric Power System

    Energy Technology Data Exchange (ETDEWEB)

    Akyol, Bora A.; Kirkham, Harold; Clements, Samuel L.; Hadley, Mark D.

    2010-01-27

    A key mission of the U.S. Department of Energy (DOE) Office of Electricity Delivery and Energy Reliability (OE) is to enhance the security and reliability of the nation’s energy infrastructure. Improving the security of control systems, which enable the automated control of our energy production and distribution, is critical for protecting the energy infrastructure and the integral function that it serves in our lives. The DOE-OE Control Systems Security Program provides research and development to help the energy industry actively pursue advanced security solutions for control systems. The focus of this report is analyzing how, where, and what type of wireless communications are suitable for deployment in the electric power system and to inform implementers of their options in wireless technologies. The discussions in this report are applicable to enhancing both the communications infrastructure of the current electric power system and new smart system deployments. The work described in this report includes a survey of the following wireless technologies: • IEEE 802.16 d and e (WiMAX) • IEEE 802.11 (Wi-Fi) family of a, b, g, n, and s • Wireless sensor protocols that use parts of the IEEE 802.15.4 specification: WirelessHART, International Society of Automation (ISA) 100.11a, and Zigbee • The 2, 3, and 4 generation (G )cellular technologies of GPRS/EDGE/1xRTT, HSPA/EVDO, and Long-Term Evolution (LTE)/HSPA+UMTS.

  14. On the safeness of examinees and the reliability of system

    International Nuclear Information System (INIS)

    Kudo, Kazumi; Kanda, Kosuke; Saito, Kazuhiko; Maesawa, Tsuneharu; Idekami, Tomio

    1979-01-01

    The control technique of the reliability of examination system was investigated from the viewpoint of patient safety and image information, based on the prevention of microshock owing to circulatory organ checking system. As for the equipments in hospitals, the size of rooms, air conditioning system, power source installation, earth and piping arrangements should be fully discussed at the planning stage. EPR system must be introduced for the prevention for microshock. Intensive education and training are required for operators to secure safeness in operation. Thorough care should be taken to prevent bacilli infection. Further examinations were made on the control technique of the reliability of photographing system from viewpoint of image information, and it is necessary to study the factors for obtaining the reliability of compound machinery components and the devices of generating radiation. (Kobatake, H.)

  15. A Reliability Assessment Method for the VHTR Safety Systems

    International Nuclear Information System (INIS)

    Lee, Hyung Sok; Jae, Moo Sung; Kim, Yong Wan

    2011-01-01

    The Passive safety system by very high temperature reactor which has attracted worldwide attention in the last century is the reliability safety system introduced for the improvement in the safety of the next generation nuclear power plant design. The Passive system functionality does not rely on an external source of energy, but on an intelligent use of the natural phenomena, such as gravity, conduction and radiation, which are always present. Because of these features, it is difficult to evaluate the passive safety on the risk analysis methodology having considered the existing active system failure. Therefore new reliability methodology has to be considered. In this study, the preliminary evaluation and conceptualization are tried, applying the concept of the load and capacity from the reliability physics model, designing the new passive system analysis methodology, and the trial applying to paper plant.

  16. System ergonomics as an approach to improve human reliability

    International Nuclear Information System (INIS)

    Bubb, H.

    1988-01-01

    The application of system technics on ergonomical problems is called system ergonomics. This enables improvements of human reliability by design measures. The precondition for this is the knowledge of how information processing is performed by man and machine. By a separate consideration of sensory processing, cognitive processing, and motory processing it is possible to have a more exact idea of the system element 'man'. The system element 'machine' is well described by differential equations which allow an ergonomical assessment of the manouverability. The knowledge of information processing of man and machine enables a task analysis. This makes appear on one hand the human boundaries depending on the different properties of the task and on the other hand suitable ergonomical solution proposals which improve the reliability of the total system. It is a disadvantage, however, that the change of human reliability by such measures may not be quoted numerically at the moment. (orig.)

  17. STRUCTURAL FLUCTUATIONS, ELECTRICAL RESPONSE AND THE RELIABILITY OF NANOSTRUCTURES (FINAL REPORT)

    Energy Technology Data Exchange (ETDEWEB)

    Philip J. Rous; Ellen D. Williams; Michael S. Fuhrer

    2006-07-31

    The goal of the research supported by DOE-FG02-01ER45939 was to synthesize a number of experimental and theoretical approaches to understand the relationship between morphological fluctuations, the electrical response and the reliability (failure) of metallic nanostructures. The primary focus of our work was the study of metallic nanowires which we regard as prototypical of nanoscale interconnects. Our research plan has been to link together these materials properties and behaviors by understanding the phenomenon of, and the effects of electromigration at nanometer length scales. The thrust of our research has been founded on the concept that, for nanostructures where the surface-to-volume ratio is necessarily high, surface diffusion is the dominant mass transport mechanism that governs the fluctuations, electrical properties and failure modes of nanostructures. Our approach has been to develop experimental methods that permit the direct imaging of the electromagnetic distributions within nanostructures, their structural fluctuations and their electrical response. This experimental research is complemented by a parallel theoretical and computational program that describes the temporal evolution of nanostructures in response to current flow.

  18. Plant and control system reliability and risk model

    International Nuclear Information System (INIS)

    Niemelae, I.M.

    1986-01-01

    A new reliability modelling technique for control systems and plants is demonstrated. It is based on modified boolean algebra and it has been automated into an efficient computer code called RELVEC. The code is useful for getting an overall view of the reliability parameters or for an in-depth reliability analysis, which is essential in risk analysis, where the model must be capable of answering to specific questions like: 'What is the probability of this temperature limiter to provide a false alarm', or 'what is the probability of air pressure in this subsystem to drop below lower limit'. (orig./DG)

  19. Solar electric power generation photovoltaic energy systems

    CERN Document Server

    Krauter, Stefan CW

    2007-01-01

    Solar electricity is a viable, environmentally sustainable alternative to the world's energy supplies. In support, this work examines the various technical parameters of photovoltaic systems. It analyzes the study of performance and yield (including optical, thermal, and electrical parameters and interfaces).

  20. 49 CFR 238.425 - Electrical system.

    Science.gov (United States)

    2010-10-01

    ... protected with a lightning arrestor, automatic circuit breaker, and overload relay. The lightning arrestor... the operating environment. (2) The electronic equipment shall not produce electrical noise that...) Electrical and electronic systems of equipment shall be capable of operation in the presence of external...