Sample records for reliable power supplies

  1. Reliability Estimates for Power Supplies

    Lee C. Cadwallader; Peter I. Petersen


    Failure rates for large power supplies at a fusion facility are critical knowledge needed to estimate availability of the facility or to set priorties for repairs and spare components. A study of the "failure to operate on demand" and "failure to continue to operate" failure rates has been performed for the large power supplies at DIII-D, which provide power to the magnet coils, the neutral beam injectors, the electron cyclotron heating systems, and the fast wave systems. When one of the power supplies fails to operate, the research program has to be either temporarily changed or halted. If one of the power supplies for the toroidal or ohmic heating coils fails, the operations have to be suspended or the research is continued at de-rated parameters until a repair is completed. If one of the power supplies used in the auxiliary plasma heating systems fails the research is often temporarily changed until a repair is completed. The power supplies are operated remotely and repairs are only performed when the power supplies are off line, so that failure of a power supply does not cause any risk to personnel. The DIII-D Trouble Report database was used to determine the number of power supply faults (over 1,700 reports), and tokamak annual operations data supplied the number of shots, operating times, and power supply usage for the DIII-D operating campaigns between mid-1987 and 2004. Where possible, these power supply failure rates from DIII-D will be compared to similar work that has been performed for the Joint European Torus equipment. These independent data sets support validation of the fusion-specific failure rate values.

  2. Injector power supplies reliability improvements at the Advanced Photon Source.

    Hillman, A.; Pasky, S.; Sereno, N.; Soliday, R.; Wang, J.


    Operational goals for the Advanced Photon Source (APS) facility include 97% availability and a mean time between unscheduled beam losses (faults) of 70 hours, with more than 5000 user hours of scheduled beam per year. To meet this objective, our focus has been maximizing the mean time between faults (MTBF). We have made various hardware and software improvements to better operate and monitor the injector power supply systems. These improvements have been challenging to design and implement in light of the facility operating requirements but are critical to maintaining maximum reliability and availability of beam for user operations. This paper presents actions taken as well as future plans to continue improving injector power supply hardware and software to meet APS user operation goals. The Advanced Photon Source (APS) has two major components. The storage ring (SR) accelerator is the primary accelerator that delivers X-ray beams to users and uses over 1,400 power supplies. The injector accelerators provide beam to the SR and use 361 different supplies. The control system ranges from the standard VME-IOC and Allen Bradley to GESPAC with additional mini-PLCs for monitoring. Injector power supplies range from {approx}30 watts DC to a ramped peak of 4.6 megawatts in 250 ms. Finally, all accelerators use pulsed supplies, and some of them deliver peak power in megawatts. In the SR, each multipole and corrector magnet is separately powered, with only the main dipole magnets on a common bus. Independent power supplies provide increased flexibility, but place additional demands on power supply reliability. The APS reliability goals are 97% availability and 70 hours mean time to unscheduled beam loss. There are 5,129 user hours scheduled per year, 1,315 hours used for machine studies, and the remaining 2,316 hours used for maintenance. The present annual operating schedule provides for three user runs (typically 10 to 12 weeks long), and three machine shutdowns (typically


    Grigorash O. V.


    Full Text Available The level of technical development today requires the creation of highly effective, including reliable, uninter-rupted power supply systems. We have shown modern requirements and design features of modern systems of uninterruptible power supply, which should be built on a modular principle. It is shown that the problem of synthesis of systems in a modular approach is addressing three issues: development of the structure of the system subject to the requirements of consumers to quality of power and the allowable time of power outage; determining the required level redundancy of major functional units (blocks, elements to ensure the required reliability of the system; - ensuring the most effective interconnection of modules, including electromagnetic compatibility, and the rational use during normal and emergency operation of the system. We have proposed new structural solution of the main functional units and uninterrupted power supply systems in modular design. To reduce EMI and improve efficiency uninterruptible power supply systems in the design of static converters we need to use a transformer with a rotating magnetic field. In addition, the prospective current is to be used as a source of renewable energy. Another promising approach is the use of direct frequency converters as voltage stabilizers and frequency of the current

  4. Potential for deserts to supply reliable renewable electric power

    Labordena, Mercè; Lilliestam, Johan


    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

  5. Research of Reliable Power Supply Schemes for OOO Gazprom Production Yamburg Gas Field

    Askarov Alisher


    Full Text Available In article the analysis of substation electric part for the enterprises an oil and gas complex power supply is carried out: structure and switchgear schemes, uninterrupted reserve sources structure. Recommendations for power supply reliability are made.

  6. Higher Power Supply Reliability of Agro-Industrial Complex (AIC Consumers

    V. I. Rusan


    Full Text Available The paper presents the developed methodology that has been used for making calculations of main reliability indices for existing electric power supply circuits of AIC consumers. Some measures pertaining to provision of higher reliability are given in the paper. The paper contains calculations of changes in respect of reliability indices and reduction in cost of supply lost due to power supply interruptions in case of introduction of the proposed  measures.


    A. L. Starzhinskij


    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.

  8. Climate protection and reliability of supply. Development of a sustainable power supply concept; Klimaschutz und Versorgungssicherheit. Entwicklung einer nachhaltigen Stromversorgung

    Klaus, Thomas; Loreck, Charlotte; Mueschen, Klaus


    Germany, like other states, committed itself to sustainable development in the Rio declaration of 1992. The boundary conditions for this are set by nature itself, whose laws must be respected if goals like reliability of supply and economic efficiency are to be achieved. This study of the Federal Environmental Office shows how sustainable power supply can be achieved. It is possible to combine climate protection, reliability of supply and economic efficiency, even without nuclear power and without constructing new conventional power plants that do not have the function of combined heat and power generation. (orig.)

  9. A simple, robust and reliable wind diesel concept for remote power supply

    Lundsager, P.; Bindner, H.


    The paper introduces a Wind Diesel concept suitable for remote communities, the 'Simple, Robust and Reliable Concept' developed at Riso. All components are standard components, the system is self regulating using the component controllers and there is no power electronics. The paper documents...... a performance in terms of fuel savings and power quality that makes the concept a commercially viable option for including wind power in remote power supply systems....

  10. Power Supply Reliability Assessment in UPFC-installed Transmission System for ATC Enhancement Considering Transient Stability

    Masuta, Taisuke; Yokoyama, Akihiko

    With recent development of power electronics technology, power system stability enhancement and optimal power flow control by using Flexible AC Transmission System (FACTS) devices have so far been studied. The FACTS devices to relieve multiple constraints can also make it possible to enhance Available Transfer Capability (ATC) without construction of new transmission lines. The previous research revealed that ATC is expanded by avoiding multiple constraints in OPF using Unified Power Flow Controller (UPFC). For long-term operation of such ATC-expanded power system, it is necessary to evaluate power system reliability. In this paper, the evaluation method of supply reliability for UPFC-installed power system is proposed. Both thermal capacity and transient stability constraints are considered. The effectiveness of the proposed method is shown by numerical examples for IEEJ East10-machine test system.

  11. Reliability and Power Quality Evaluation of High-Voltage Supplied Customer

    Yoshino, Jun; Kita, Hiroyuki; Tanaka, Eiichi; Hasegawa, Jun; Kubo, Hiroshi; Yonaga, Shigeru

    Recently, a number of electric consumers have concerned about the reliability of electricity to be served. For example, some consumers need the electricity with a higher reliability by the automation of manufacturing processes. On the other hand, some consumers need the electricity of a cheaper price even if the reliability becomes a little worse. Under such circumstances, it is necessary that power suppliers evaluate the needs of every consumers precisely and propose the most desirable measures for meeting their requirements. This paper develops a tool to analyze the reliability for high-voltage supplied consumers quantitatively. Further, this paper presents a method for evaluating the outage cost of consumers to help them choose the most appropriate measures for maintaining the reliability. The proposed method applies the fuzzy reasoning approach. The validity of the proposed method is ascertained through some numerical simulations.

  12. Improving the Reliability of LDP through the Divergence of Power Supply for LDP

    Lee, Bang Sil [KHNP CRI, Daejeon (Korea, Republic of)


    The representative operating systems are Large Display Panel (LDP), Operator Workstation (OWS), Computerized Procedure System (CPS). The LDP provides the information which is plant essential safety function, plant operating mode, the state of major operating variable and the important alarm to operator continuously. In case of malfunction and switchover fail of the inverter, it is possible to occur the power loss of LDP. The power of LDP and operator console workstation had been supplied by only 2 non-safety Power Line1/Power Line2 (P.L1/P.L2). This study mentioned the divergence of power for LDP as method of power loss caused by unreliability of inverter. Ultimately, LDP power line has been added, and then it is more improved on the safety of LDP operation than before. So Shin-Kori 3,4 can enhance the reliability and economic, safety of plant.

  13. Supply chain reliability modelling

    Eugen Zaitsev


    Full Text Available Background: Today it is virtually impossible to operate alone on the international level in the logistics business. This promotes the establishment and development of new integrated business entities - logistic operators. However, such cooperation within a supply chain creates also many problems related to the supply chain reliability as well as the optimization of the supplies planning. The aim of this paper was to develop and formulate the mathematical model and algorithms to find the optimum plan of supplies by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Methods: The mathematical model and algorithms to find the optimum plan of supplies were developed and formulated by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Results and conclusions: The problem of ensuring failure-free performance of goods supply channel analyzed in the paper is characteristic of distributed network systems that make active use of business process outsourcing technologies. The complex planning problem occurring in such systems that requires taking into account the consumer's requirements for failure-free performance in terms of supply volumes and correctness can be reduced to a relatively simple linear programming problem through logical analysis of the structures. The sequence of the operations, which should be taken into account during the process of the supply planning with the supplier's functional reliability, was presented.

  14. Improvement of quality and reliability of electric power supply using the supply transformer with under load tap change device

    Grabko, Volodymyr V.; Balzan, Igor V.; Smolarz, Andrzej; Asambay, Azat


    On the base of the analysis of laws on voltage regulation by the supply transformers with the under load tap change device, the paper presents the modified regulation law, the use of which, unlike the known ones, allows to limit the number of tap changing of the supply transformer, which results in improvement of voltage quality of the consumers and the reliability of the under voltage tap change device operation.

  15. Solar battery power supply: A reliable power supply system for nursing clinic in Australia`s remote areas

    Zahedi, A. [Monash Univ., Caulfield (Australia). Div. of Electrical and Computer Systems Engineering


    Design and performance investigation of a new solar-battery system to power health clinics in Australia`s remote and isolated areas is a research project being conducted in the Department. The objective of this paper is to present the solar-battery system and to discuss the design factors of the system.

  16. Reliability and safety of the electrical power supply complex of the Hanford production reactors

    Robbins, F.D.


    Safety has been and must continue to be the inviolable modulus by which the operation of a nuclear reactor must be judged. A malfunction in any reactor may well result in a release of fission products which may dissipate over a wide geographical area. Such dissipation may place the health, happiness and even the lives of the people in the region in serious jeopardy. As a result, the property damage and liability cost may reach astronomical values in the order of magnitude of billions of dollars. Reliability of the electrical network is an indispensable factor in attaining a high order of safety assurance. Progress in the peaceful use of atomic energy may take the form of electrical power generation using the nuclear reactor as a source of thermal energy. In view of these factors it seems appropriate and profitable that a critical engineering study be made of the safety and reliability of the Hanford reactors without regard to cost economics. This individual and independent technical engineering analysis was made without regard to Hanford traditional engineering and administration assignments. The main objective has been to focus attention on areas which seem to merit further detailed study on conditions which seem to need adjustment but most of all on those changes which will improve reactor safety. This report is the result of such a study.

  17. To Problem of Electric Supply Reliability for Consumers of Agro-Industrial Complex with Development of Market Relations in Electric Power Industry

    G. F. Kutsenko


    Full Text Available The paper considers a number of problems concerning relations between power-supply organizations and agro-industrial complex enterprises in respect of reliability of power supply to electro-receivers. Some concrete measures that are supposed to improve these relations under modem conditions are offered in the paper/

  18. Analysis and Prospect of Power Supply Reliability Management in China%我国供电可靠性管理的现状分析与展望



    供电可靠性是整个电力系统对电力用户服务水平的综合体现,供电可靠性指标直接反映了电源供给能力、各级电网结构、供电设备健康状况和生产管理水平.文章介绍了我国当前供电可靠性指标现状,并对供电可靠性指标的发展趋势、分布情况、停电原因进行了分析,总结了当前面临的问题和挑战,对未来可靠性管理工作的发展进行了展望.%Power supply reliability is the comprehensive reflection of the service quality of power systems to power consumers.Power supply reliability index directly reflects the supply capacity of power sources,the gird structure of various voltage levels,the health status of power supply devices and production management level.The current status of the reliability index of power supply in China is introduced,the development trend,distribution and causes for power outage of the reliability index are analyzed,the existing problems and challenges are summarized,and the development prospect for the future power supply reliability management are proposed.

  19. Power supply reliability management of urban distribution network in Yinchuan Power Supply Bureau%银川供电局城市配电网供电可靠性管理



    From the current situation of the power grid and reliability analyzing the improvement and effects of the urban distribution network in Yinchuan Electric Power Supply Bureau,.Puts forward the management measures from the aspects of distribution network planning management,central dispatching management,reliability index check,strengthening reliable data management and regulating power cut management,and analyzes the technological measures of improving power supply reliability from the aspects of the technology standard,structure optimization,transmission line improvement of the distribution network,,switch equipment protection allocation and new equipment application.%针对近几年来银川供电局城市配电网改造实施情况,从配电网规划管理、集中调度管理、可靠性指标考核、可靠性数据管理、规范停电管理流程等方面分析并提出了提高供电可靠性的管理措施;从配电网技术标准、配电网结构优化、配电网线路改进、开关设备保护配置及新设备应用等方面分析并提出了提高供电可靠性的技术措施。

  20. Debugging on High-voltage Power Supply,Focusing Power Supply and Magnetic Field Power Supply

    TU; Rui


    High-voltage power supply,focusing power supply and magnetic field power supply are the main parts of the power supply system of the EMIS(Electro-Magnetic Isotope Separator)supplying the ion source.In 2015,a high-voltage power supply,power supply for focusing and

  1. Solar mobile power supply

    Hu, Libian


    The solar mobile power supply is a comprehensive energy saving and environment protective product. Besides, it consists of solar panels, storage battery and controller as well as other important components. Based on the traditional solar charging circuit, this solar power supply combines the 5V USB interface and 12V adjustable circuit as well as the 220V inverter and power adapter to greatly improve the function of the power system.

  2. Reliability of Power Electronic Converter Systems

    -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......-tolerant adjustable speed drive systems; mission profile oriented reliability design in wind turbine and photovoltaic systems; reliability of power conversion systems in photovoltaic applications; power supplies for computers; and high-power converters. Reliability of Power Electronic Converter Systems is essential...... reading for researchers, professionals and students working with power electronics and their applications, particularly those specializing in the development and application of power electronic converters and systems....

  3. Mobile Uninterruptible Power Supply

    Mears, Robert L.


    Proposed mobile unit provides 20 kVA of uninterruptible power. Used with mobile secondary power-distribution centers to provide power to test equipment with minimal cabling, hazards, and obstacles. Wheeled close to test equipment and system being tested so only short cable connections needed. Quickly moved and set up in new location. Uninterruptible power supply intended for tests which data lost or equipment damaged during even transient power failure.

  4. Radioisotope Power Supply Project

    National Aeronautics and Space Administration — Between 1998 and 2003, Hi-Z Technology developed and built a 40 mW radioisotope power supply (RPS) that used a 1 watt radioisotope heater unit (RHU) as the energy...

  5. A new bipolar Qtrim power supply system

    Mi, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Drozd, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Nolan, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Orsatti, F. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Heppener, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Di Lieto, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Schultheiss, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Samms, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Zapasek, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Sandberg, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.


    This year marks the 15th run of RHIC (Relativistic Heavy Ion Collider) operations. The reliability of superconducting magnet power supplies is one of the essential factors in the entire accelerator complex. Besides maintaining existing power supplies and their associated equipment, newly designed systems are also required based on the physicist’s latest requirements. A bipolar power supply was required for this year’s main quadruple trim power supply. This paper will explain the design, prototype, testing, installation and operation of this recently installed power supply system.

  6. Reliability of the TJ-II power supply system: Collection and analysis of the operational experience data

    Izquierdo, Jesus [Fusion Energy Engineering Laboratory, Seccio d' Enginyeria Nuclear, Universitat Politecnica de Catalunya, Avda. Diagonal 647, 08028 Barcelona (Spain)], E-mail:; Dies, Javier; Garcia, Jeronimo; Tapia, Carlos [Fusion Energy Engineering Laboratory, Seccio d' Enginyeria Nuclear, Universitat Politecnica de Catalunya, Avda. Diagonal 647, 08028 Barcelona (Spain); Alonso, Javier; Ascasibar, Enrique; Medrano, Mercedes; Mendez, Purificacion; Rodriguez, Lina [Asociacion EURATOM-CIEMAT para la Fusion, Avda. Complutense 22, Madrid (Spain)


    During a TJ-II pulse, the provision of magnetic fields requires a total amount of power exceeding 80 MVA. Such amount of power is supplied by a 132 MVA flywheel generator (15 kV output voltage, 80-100 Hz output frequency) and the related motor, transformers, breakers, rectifiers, regulators, protections, busbars, connections, etc. Failure data of these main components have been collected identified and processed including information on failure modes and, where possible, causes of the failures. Main statistical values about failure rates for the period from May of 1998 to December of 2004 have been calculated and are ready to be compared with those of the International Fusion Component Failure Rate Database (FCFR-DB)

  7. Power electronics reliability analysis.

    Smith, Mark A.; Atcitty, Stanley


    This report provides the DOE and industry with a general process for analyzing power electronics reliability. The analysis can help with understanding the main causes of failures, downtime, and cost and how to reduce them. One approach is to collect field maintenance data and use it directly to calculate reliability metrics related to each cause. Another approach is to model the functional structure of the equipment using a fault tree to derive system reliability from component reliability. Analysis of a fictitious device demonstrates the latter process. Optimization can use the resulting baseline model to decide how to improve reliability and/or lower costs. It is recommended that both electric utilities and equipment manufacturers make provisions to collect and share data in order to lay the groundwork for improving reliability into the future. Reliability analysis helps guide reliability improvements in hardware and software technology including condition monitoring and prognostics and health management.

  8. 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

    Bonfietti, Gerson


    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)

  9. Rechargeable power supply

    Den Uijl, S.; Bouman, C.; Smit, W.


    The invention relates to a rechargeable power supply suitable to be used in a battery-operated device comprising at least one supercapacitor and at least a first and a second DC-DC converter connected in series, wherein the supercapacitor is connectable to an entry of the first DC-DC converter and t

  10. Discontinuous Mode Power Supply

    Lagadinos, John; Poulos, Ethel


    A document discusses the changes made to a standard push-pull inverter circuit to avoid saturation effects in the main inverter power supply. Typically, in a standard push-pull arrangement, the unsymmetrical primary excitation causes variations in the volt second integral of each half of the excitation cycle that could lead to the establishment of DC flux density in the magnetic core, which could eventually cause saturation of the main inverter transformer. The relocation of the filter reactor normally placed across the output of the power supply solves this problem. The filter reactor was placed in series with the primary circuit of the main inverter transformer, and is presented as impedance against the sudden changes on the input current. The reactor averaged the input current in the primary circuit, avoiding saturation of the main inverter transformer. Since the implementation of the described change, the above problem has not reoccurred, and failures in the main power transistors have been avoided.

  11. Improving Power Converter Reliability

    Ghimire, Pramod; de Vega, Angel Ruiz; Beczkowski, Szymon


    The real-time junction temperature monitoring of a high-power insulated-gate bipolar transistor (IGBT) module is important to increase the overall reliability of power converters for industrial applications. This article proposes a new method to measure the on-state collector?emitter voltage...... of a high-power IGBT module during converter operation, which may play a vital role in improving the reliability of the power converters. The measured voltage is used to estimate the module average junction temperature of the high and low-voltage side of a half-bridge IGBT separately in every fundamental...... is measured in a wind power converter at a low fundamental frequency. To illustrate more, the test method as well as the performance of the measurement circuit are also presented. This measurement is also useful to indicate failure mechanisms such as bond wire lift-off and solder layer degradation...

  12. Reliability of power connections

    BRAUNOVIC Milenko


    Despite the use of various preventive maintenance measures, there are still a number of problem areas that can adversely affect system reliability. Also, economical constraints have pushed the designs of power connections closer to the limits allowed by the existing standards. The major parameters influencing the reliability and life of Al-Al and Al-Cu connections are identified. The effectiveness of various palliative measures is determined and the misconceptions about their effectiveness are dealt in detail.

  13. Power electronics reliability.

    Kaplar, Robert James; Brock, Reinhard C.; Marinella, Matthew; King, Michael Patrick; Stanley, James K.; Smith, Mark A.; Atcitty, Stanley


    The project's goals are: (1) use experiments and modeling to investigate and characterize stress-related failure modes of post-silicon power electronic (PE) devices such as silicon carbide (SiC) and gallium nitride (GaN) switches; and (2) seek opportunities for condition monitoring (CM) and prognostics and health management (PHM) to further enhance the reliability of power electronics devices and equipment. CM - detect anomalies and diagnose problems that require maintenance. PHM - track damage growth, predict time to failure, and manage subsequent maintenance and operations in such a way to optimize overall system utility against cost. The benefits of CM/PHM are: (1) operate power conversion systems in ways that will preclude predicted failures; (2) reduce unscheduled downtime and thereby reduce costs; and (3) pioneering reliability in SiC and GaN.

  14. Measurement of Pulsed Power Supply


    Power supply system is an important subsystem of CSR. To apply for running, the parameters of power supply must be fit the design’s demands. We have tested all prototype of power supply as follows.The DC stability measurement is that the power supply runs in certain current level from the lower value to the normal value. In every current level, we acquire about 550 data by digital meter (model 7081) in 8 h.


    O. O. Matusevych


    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.

  16. 地铁牵引供电系统可靠性分析%Analysis of the Reliability of Power Supply System for Metro Traction



    The development of the social economy has driven continued growth in city traffic. The normal operation of po- wer supply system provides the necessary power for subway, and in case of power outage, the transportation lines wil be paralyzed and worse more, this may endanger the safety of the passengers. Therefore, it is particularly important to study the reliability of metro traction power supply system.%社会经济的发展带动着城市交通量的持续增长。供电系统为地铁的正常运营提供所必须的电能,一旦发生供电中断,整个交通运输线路就会发生瘫痪,严重的甚至危害到乘客及客运安全。所以,对地铁牵引供电系统的可靠性展开研究尤为重要。

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

    Mark Ndubuka NWOHU


    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.

  18. Reliability Block Diagram (RBD) Analysis of NASA Dryden Flight Research Center (DFRC) Flight Termination System and Power Supply

    Morehouse, Dennis V.


    In order to perform public risk analyses for vehicles containing Flight Termination Systems (FTS), it is necessary for the analyst to know the reliability of each of the components of the FTS. These systems are typically divided into two segments; a transmitter system and associated equipment, typically in a ground station or on a support aircraft, and a receiver system and associated equipment on the target vehicle. This analysis attempts to analyze the reliability of the NASA DFRC flight termination system ground transmitter segment for use in the larger risk analysis and to compare the results against two established Department of Defense availability standards for such equipment.

  19. Mars sample return power supply

    Hoang, Don; Ludwigs, Sharon; Schmitz, Paul; Wright, John

    A power supply is designed for a vehicle able to operate on the surface of Mars for a period of 5 to 10 years. This vehicle will be used for sample and data collection. The design is based on the assumption that the vehicle will be unmanned. Also, there will be no means by which components could be repaired or replaced while on the Martian surface. A consequence of this is that all equipment must meet high standards of reliability and, if possible, redundancy. Power will be supplied to the vehicle by means of a General Purpose Heat Source capable of producing a minimum of 7 kW of thermal power. The heat generated from the General Purpose Heat Source will be transferred to a Stirling engine via hot side heat pipes. The Stirling engine will then convert this heat into 2 kW of electrical power. Cold side heat pipes will be used to carry away waste heat, which will be released to the Martian environment via radiators connected to the end of the cold side heat pipes.


    Grigorash O. V.


    Full Text Available We have revealed the main reasons for interruptions in power supply to consumers of electricity. To improve the reliability and the efficiency of power supply for responsible consumers, we have proposed to develop energy efficient combined energy-saving systems for uninterrupted power supply with use of renewable energy sources. The article lists major principles of the development of such systems; it shows the necessity of constructing a generalized schema that contains the possible types and the sources of electric power converters. It also reveals the modern requirements to systems of uninterrupted energy supply. To improve the operational and technical characteristics of the uninterruptible power supply, it has been proposed to use a new circuitry that includes a contactless power generators, the direct frequency converters used to stabilize the voltage and frequency of the current generators of wind turbines, static converters made with the use of single-phase transformers with rotating magnetic field, universal static converters that can operate in the regimes of known types of converters. The article presents features of the modular construction of systems of uninterrupted energy supply and optimization of their structural decisions on key performance criteria. It shows the algorithm of synthesis of structural designs of combined systems of uninterrupted power supply. An important step for further research with the aim of improving operational and technical characteristics of the combination of uninterrupted power supply systems is the mathematical modeling of physical processes in power circuits of the system in both normal and emergency modes of operation

  1. Modular High Voltage Power Supply

    Newell, Matthew R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    The goal of this project is to develop a modular high voltage power supply that will meet the needs of safeguards applications and provide a modular plug and play supply for use with standard electronic racks.

  2. Assessment of power reliability and improvement potential by using ...

    Assessment of power reliability and improvement potential by using smart reclosers. ... Electric reliability has affected social well being, public health, water supply, ... of smart reclosers improves the reliability of the distribution network by 75% ...

  3. Practical switching power supply design

    Brown, Martin C


    Take the ""black magic"" out of switching power supplies with Practical Switching Power Supply Design! This is a comprehensive ""hands-on"" guide to the theory behind, and design of, PWM and resonant switching supplies. You'll find information on switching supply operation and selecting an appropriate topology for your application. There's extensive coverage of buck, boost, flyback, push-pull, half bridge, and full bridge regulator circuits. Special attention is given to semiconductors used in switching supplies. RFI/EMI reduction, grounding, testing, and safety standards are also deta

  4. CSR Pulsed Switching Power Supplies


    In 2001, CSR power supply system made a great progress. Three prototypes were designed for CSR quadruple and correct magnet. Three different companies provided the three prototypes, but the same circuit-chopper were employed. The simplified diagram is showed in Fig.1. All pulsed switching power supply prototypes were tested successfully before the end of 2001.

  5. 基于小g函数法的客户侧供电可靠性分析的研究%Power Supply Reliability Analysis on Customer Side Based on Small g Function Method

    梁瑞莹; 黄玉昆


    针对目前我国对于供电可靠性只统计到中压客户,并不能全面反映各类用电客户实际的供电可靠性的缺陷,为了找出计及中压与计及低压两者之间供电可靠性的差异及其变化的规律,本文对低压客户侧供电可靠性的主要评价指标、基础数据的建立及各类停电数据的采集进行了分析,提出了采用“小g函数法”进行差异化分析,且以仿真数据输入的方式计算了同一外部环境和停电事件下的两种可靠性指标,经分析比较后得出了计及中、低压客户的供电可靠性指标变化差异的规律,为计及低压客户供电可靠性计算方式提供了理论依据.%In our country, it only counts medium voltage customers for power supply reliability, not fully reflect the defects of actual power supply reliability of various types of electricity customers. In order to find out the differences of power supply reliability between inclusive medium voltage and low voltage as well as the changing law, this paper made analysis on main evaluation index of the power supply reliability of the low voltage customer side, the establishment of the basic data and collection of various types of power outage data, and proposed to use "small g function method" to conduct gap analysis, and calculated two kinds of reliability index under the same external environment and the power outage with the way of simulation data input, through the comparative analysis, it gets the law of difference of changing in power supply reliability of inclusive mid-voltage and low-voltage customers, providing a theoretical basis for calculation way of power supply reliability inclusive low-voltage customer supply reliability.

  6. Fault tolerant system design for uninterruptible power supplies

    B. Y. Volochiy; D. S. Kuznetsov


    The problem of design for reliability of a fault tolerant system for uninterruptible power supplies is considered. Configuration of a fault tolerant system determines the structure of an uninterruptible power supply: power supply built from modules of the same type, stand-by sliding reserve for them, twice total reserve of the power supply with two accumulator batteries, the controls and diagnostics means. The developed tool for automated analytical model of fault tolerant systems generation ...


    Driver, G.E.


    High voltage, direct current power supplies are described for use with battery powered nuclear detection equipment. The particular advantages of the power supply described, are increased efficiency and reduced size and welght brought about by the use of transistors in the circuit. An important feature resides tn the employment of a pair of transistors in an alternatefiring oscillator circuit having a coupling transformer and other circuit components which are used for interconnecting the various electrodes of the transistors.

  8. Stabilized DC power supplies; Alimentations continues stabilisees

    Boutouyrie, B. [Ecole Superieure d' Electricite, 91 - Gif-sur-Yvette (France)


    This article deals with DC power supplies devoted to electronic equipments with a power comprised between 10 W to 5000 W with a AC (50 Hz to 400 Hz) or a DC input and one or several DC outputs of 200 V maximum. The broad outlines of the main technical problems are presented and a particular care is given to the parameters interesting for user's applications: 1 - principles (in-series regulation and switching power supplies); 2 - noise in switching power supplies (disturbances transferred by conductors and frame, radio-frequency noise, noise measurement, output waveform); 3 - disturbances standardization (classes, regulation and label, standards); 4 - mean time between failure (MTBF) and reliability (calculated or demonstrated MTBF, reliability, reliability-limiting components, new test and burn-in methods); 5 - efficiency and cooling; 6 - applications (input current, sense, decoupling, current limitation, in-parallel installation, redundancy, battery charging, use with inductive load, power factor correction, modular power supplies); 7 - some advices. (J.S.)

  9. Power Industry Reliability Coordination in Asia in a Market Environment

    Nikolai I. Voropai


    Full Text Available This paper addresses the problems of power supply reliability in a market environment. The specific features of economic interrelations between the power supply organization and consumers in terms of reliability assurance are examined and the principles of providing power supply reliability are formulated. The economic mechanisms of coordinating the interests of power supply organization and consumers to provide power supply reliability are discussed. Reliability of restructuring China's power industry is introduced. Some reliability data is provided. The data shows that the reliability level has increased significantly in the past two decades. More and more measures are being applied to guarantee reliability of the restructured power systems. The reliability issues and challenges that are facing the Chinese power industry are considered The paper, then examines the evolution of power grids in India, the establishment of a regulatory framework, and operational philosophy in reliability aspects of long-, mid- as well as short-term (operational / outage planning. Grid security, restoration, and mock trial for black start, etc. from the reliability angle are considered. Related issues for islanding operation to improve service reliability for Thailand's Electric Power System are then analyzed.

  10. A study on reliability of power customer in distribution network

    Liu, Liyuan; Ouyang, Sen; Chen, Danling; Ma, Shaohua; Wang, Xin


    The existing power supply reliability index system is oriented to power system without considering actual electricity availability in customer side. In addition, it is unable to reflect outage or customer’s equipment shutdown caused by instantaneous interruption and power quality problem. This paper thus makes a systematic study on reliability of power customer. By comparing with power supply reliability, reliability of power customer is defined and extracted its evaluation requirements. An indexes system, consisting of seven customer indexes and two contrast indexes, are designed to describe reliability of power customer from continuity and availability. In order to comprehensively and quantitatively evaluate reliability of power customer in distribution networks, reliability evaluation method is proposed based on improved entropy method and the punishment weighting principle. Practical application has proved that reliability index system and evaluation method for power customer is reasonable and effective.

  11. Estimating a municipal water supply reliability

    O.G. Okeola


    Full Text Available The availability and adequacy of water in a river basin determine the design of water resources projects such as water supply. There is a further need to regularly appraise availability of such resource for municipality at a distant future to help in articulating contingent plan to handle its vulnerability. This paper attempts to empirically determine the reliability of water resource for a municipal water supply. An approach was first developed to estimate municipality water demand that lack socioeconometric data using a purpose-specific model. Hydrological assessment of river Oyun basin was carried out using Markov model and sequent peak analysis to determine the reliability extent for the future demand need. The two models were then applied to Offa municipality in Kwara state, Nigeria. The finding revealed the reliability and adequacy of the resource up till year 2020. The need to start exploring a well-coordinated conjunctive use of resources is recommended. The study can serve as an organized baseline for future work that will consider physiographic characteristics of the basin and climatic dynamics. The findings can be a vital input into the demand management process for long-term sustainable water supply of the town and by extension to urban township with similar characteristic.


    Denisenko E. A.


    Full Text Available The article describes the main block diagrams of three types of uninterruptible power supply: backup; interactive; double conversion. The main functions are: the function backup or emergency source of electrical power; the function of protective devices (from an overload currents and short-circuit; improving the quality of the power supply voltage. Alsoб we have disclosed the features of the advantages and disadvantages of uninterruptible power supplies three groups: Off-Line / Stand-By / back-up UPS (passive - reserve; Line-Interactive (line interactive type; On-Line. The article discloses new approaches to structural and schematic-based uninterruptible power supply, including at use of renewable energy, so that the failure of one of the sources does not lead to exit from the operation of the entire of power supply system. As a rule, such systems are built on a modular principle. It is shown that now for remote users from external networks is advisable to apply a system autonomous power supply, representing the totality of sources and converters of electric power, ensuring uninterrupted power supply to consumers. We have presented a typical structure of autonomous systems and given an option of the block diagram of the system and are given explanations and principles of its work. Significantly improves performance reliability of autonomous systems using the modularity of its main functional units. In addition, to increase the efficiency of the system can be through the use in the construction of transformers with static converters rotating magnetic field. To improve the weight, which is important for the transport systems, it is necessary to use links with the intermediate high-frequency electric power conversion in static converters

  13. 对提高10kV配网供电可靠性的探讨%Discussion on Improving Power Supply Reliability of 10 kV Distribution Network



    电力企业要想获得健康、稳定的发展,就必须保障供电的可靠性.保障供电的可靠性是一项具有综合性和技术性的工作,对提高配网的智能化管理水平有着重要的影响.%Electric power enterprises in order to obtain a healthy and stable development, we must guarantee the reliability of power supply. Ensuring the reliability of power supply is a comprehensive and technical work, which has an important effect on improving the level of intelligent management of the distribution network.

  14. Design of Automatic Switch Device of the Auxiliary Power Supply to a High-Reliability System in Shooting Range%靶场某高可靠系统备用电源自投装置设计

    何吉祥; 李晓波; 张昊


    In order to improve the reliability of the power supply and to ensure uninterrupted power supply of shooting range equipment,an automatic switch device of the auxiliary power supply is developed.Firstly,its composition structure and working principles are introduced;the general design thoughts and hardware design methods of the device are described in detail,mainly about the design of power plug-ins,master controller plug-ins,human-computer interaction plug-ins,current and voltage acquisition plug-ins,relay plug-in and human-machine interface plug-ins.Meanwhile software design method of the automatic switch device of the auxiliary power supply is researched;rapid and reliable power supply switching and a concise human-machine interface are realized.At last,the reliability of this device is discussed.%为了提高电源的可靠性,保证靶场设备的不间断供电,研究了一种备用电源自投装置。在介绍其组成结构和工作原理的基础上,对装置的总体设计思想和硬件设计方法进行了详细的描述,主要包括电源插件、主控制器插件、电流和电压采集插件、继电器插件、人机交互插件等关键环节的设计。同时对备用电源自投装置的软件设计方法做了研究,实现了主备电源的快速、可靠切换和简洁的人机界面。最后对该装置的可靠性问题进行了探讨。

  15. Smart Power Supply for Battery-Powered Systems

    Krasowski, Michael J.; Greer, Lawrence; Prokop, Norman F.; Flatico, Joseph M.


    A power supply for battery-powered systems has been designed with an embedded controller that is capable of monitoring and maintaining batteries, charging hardware, while maintaining output power. The power supply is primarily designed for rovers and other remote science and engineering vehicles, but it can be used in any battery alone, or battery and charging source applications. The supply can function autonomously, or can be connected to a host processor through a serial communications link. It can be programmed a priori or on the fly to return current and voltage readings to a host. It has two output power busses: a constant 24-V direct current nominal bus, and a programmable bus for output from approximately 24 up to approximately 50 V. The programmable bus voltage level, and its output power limit, can be changed on the fly as well. The power supply also offers options to reduce the programmable bus to 24 V when the set power limit is reached, limiting output power in the case of a system fault detected in the system. The smart power supply is based on an embedded 8051-type single-chip microcontroller. This choice was made in that a credible progression to flight (radiation hard, high reliability) can be assumed as many 8051 processors or gate arrays capable of accepting 8051-type core presently exist and will continue to do so for some time. To solve the problem of centralized control, this innovation moves an embedded microcontroller to the power supply and assigns it the task of overseeing the operation and charging of the power supply assets. This embedded processor is connected to the application central processor via a serial data link such that the central processor can request updates of various parameters within the supply, such as battery current, bus voltage, remaining power in battery estimations, etc. This supply has a direct connection to the battery bus for common (quiescent) power application. Because components from multiple vendors may have

  16. Reliability modelling - PETROBRAS 2010 integrated gas supply chain

    Faertes, Denise; Heil, Luciana; Saker, Leonardo; Vieira, Flavia; Risi, Francisco; Domingues, Joaquim; Alvarenga, Tobias; Carvalho, Eduardo; Mussel, Patricia


    The purpose of this paper is to present the innovative reliability modeling of Petrobras 2010 integrated gas supply chain. The model represents a challenge in terms of complexity and software robustness. It was jointly developed by PETROBRAS Gas and Power Department and Det Norske Veritas. It was carried out with the objective of evaluating security of supply of 2010 gas network design that was conceived to connect Brazilian Northeast and Southeast regions. To provide best in class analysis, state of the art software was used to quantify the availability and the efficiency of the overall network and its individual components.

  17. Measurement Practices for Reliability and Power Quality

    Kueck, JD


    regulators. The report will also serve to support activities to develop and share information among industry and regulatory participants about critical resources and practices. The toolkit has been developed by investigating the status of indices and definitions, surveying utility organizations on information sharing, and preparing summaries of reliability standards and monitoring requirements--the issues, needs, work under way, existing standards, practices and guidelines--for the following three classifications: (1) terms and definitions of reliability; (2) power quality standards, guidelines, and measurements; and (3) activities and organizations developing and sharing information on distribution reliability. As these synopses of reliability measurement practices are provided, it must be noted that an economic penalty may be associated with requiring too high a reliability level from the distribution system for all customers. It may be appropriate for the distribution system to supply only some base, generally accepted level of reliability. This base level would be adequate for the majority of customers. Users who need a higher level may find it economical to supply using distributed energy resources (DER) and other local solutions to reliability and power quality needs. Local solutions implemented by the customer may be the most cost-effective method for addressing the more stringent needs of a digital economy. These local solutions include energy storage, small distributed generators, and microgrids. This report also considers the market's role in addressing reliability issues and requirements. The customer's needs are discussed in view of issues such as power quality requirements of digital electronic equipment, the cost of outages, the cost of storage and new infrastructure, and natural gas prices. The market role in addressing these issues and requirements is explored. The economic considerations associated with the reliability issues are discussed, as well

  18. Improved reliability of power modules

    Baker, Nick; Liserre, Marco; Dupont, Laurent


    Power electronic systems play an increasingly important role in providing high-efficiency power conversion for adjustable-speed drives, power-quality correction, renewable-energy systems, energy-storage systems, and electric vehicles. However, they are often presented with demanding operating env...... temperature cycling conditions on the system. On the other hand, safety requirements in the aerospace and automotive industries place rigorous demands on reliability....

  19. 提高10kV线路供电可靠性的对策及建议%To improve the reliability of power supply countermeasures and suggestions of 10kV line



    The 10kV distribution line is the current application of one of the most extensive distribution voltage,its stable operation is directly related to the quality of power supply. Therefore,how to improve the reliability of 10kV distribution line operation,reducing the power cut accident,is the core task of power supply enterprise.In this paper,the author mainly on the factors influencing the reliability of power supply 10kV line are analyzed,and puts forward corresponding countermeasures and suggestions,for reference.%10kV配电线路是我国当前应用最为广泛的一种配电电压,它的稳定运行直接关系到供电的质量。因此,如何提高10kV配电线路运行的可靠性,减少停电事故的发生,是供电企业的核心工作任务。本文作者主要就影响10kV 线路供电可靠性的因素进行了分析,同时提出了相应的对策及建议,可供参考。

  20. Reliability Characteristics of Power Plants

    Zbynek Martinek


    Full Text Available This paper describes the phenomenon of reliability of power plants. It gives an explanation of the terms connected with this topic as their proper understanding is important for understanding the relations and equations which model the possible real situations. The reliability phenomenon is analysed using both the exponential distribution and the Weibull distribution. The results of our analysis are specific equations giving information about the characteristics of the power plants, the mean time of operations and the probability of failure-free operation. Equations solved for the Weibull distribution respect the failures as well as the actual operating hours. Thanks to our results, we are able to create a model of dynamic reliability for prediction of future states. It can be useful for improving the current situation of the unit as well as for creating the optimal plan of maintenance and thus have an impact on the overall economics of the operation of these power plants.

  1. Fault tolerant system design for uninterruptible power supplies

    B. Y. Volochiy


    Full Text Available The problem of design for reliability of a fault tolerant system for uninterruptible power supplies is considered. Configuration of a fault tolerant system determines the structure of an uninterruptible power supply: power supply built from modules of the same type, stand-by sliding reserve for them, twice total reserve of the power supply with two accumulator batteries, the controls and diagnostics means. The developed tool for automated analytical model of fault tolerant systems generation and illustration of its capabilities in determination of requirements for repair service and accumulator batteries are given.

  2. Power supply system design and build for Antarctica telescope

    Du, Fujia; Li, Hao; Li, Aiai


    Currently, more and more telescopes were built and installed in Dome A of Antarctic. The telescopes are remote controlled, unattended operation due to Dome A's environment. These telescopes must be work successfully at least one year without any failure. According to past experience, the power supply system is the weakest point in whole system. The telescopes have to stop if the power system have a problem, even a minor problem. So the high requirement for power supply system are presented. The requirement include high reliability, the self-diagnosis and perfect monitor system. Furthermore, the optic telescope only can work at night. The power source mainly relay on diesel engine. To protect the Antarctic environment and increase the life of engines. The power capacity is limited during observation. So it need the power supply system must be high power factor, high efficient. To meet these requirement, one power supply system was design and built for Antarctic telescope. The power supply system have the following features. First, we give priority to achieve high reliability. The reliability of power system was calculated and the redundant system is designed to make sure that the spare one can be work immediately when some parts have problems. Second, the perfect monitor system was designed to monitor the voltage, current, power and power factor for each power channel. The status of power supply system can be acquired by internet continuously. All the status will be logged in main computer for future analysis. Third, the PFC (Power Factor Correction) technology was used in power supply system. This technology can dramatically increase the power factor, especially in high power situation. The DC-DC inverter instead of AC-DC inverter was used for different voltage level to increase the efficient of power supply.

  3. Design of a 500 MJ, 5 MA power supply

    Pappas, J. A.; Headifen, G. R.; Weldon, J. M.; Wright, J. C.; Zowarka, R. C.; Aanstoos, T. A.; Kajs, J. H.


    The design of a 500 MJ, 5 MA power supply for rail gun experiments under the Battery Upgraded Supply (BUS) program is examined. About 50,000 12-volt lead acid batteries are required to reach this level. BUS will be required to perform up to two discharges per week. Therefore, BUS is designed to be a low-maintenance, reliable, and fault-tolerant power supply. The design of BUS and the details of its subsystems are described.

  4. Reliability Evaluation of Metro Traction Power Supply System Based on FTA and FMEA Methods%基于FTA和FMEA法的地铁牵引供电系统可靠性评估

    胡海涛; 高朝晖; 何正友; 袁林


    The traction power supply system(TPSS)is the power source to guarantee safe and reliable operation of urban mass transit. Evaluation of the reliability of the system is critical to reliability research of the whole Metro power supply system. In this paper, fault tree analysis (FTA) and failure mode and effects analysis (FMEA) were used to evaluate the reliability of one typical Metro TPSS. Firstly, the system was defined and the FMEA table was consummated. Then,through grading the system voltages,the fault tree model was built up and the minimum cut sets of the fault tree were got. Finally,by using the self-developed reliability analysis software,the reliability of three cases of power supply "was evaluated. Compared with the actual project,the validity and practical applicability of the reliability analysis method were verified.%地铁牵引供电系统是保证地铁安全可靠运行的动力来源,其可靠性分析对整个地铁供电系统的可靠性研究至关重要.本文针对某一地铁典型牵引供电系统结构,利用故障树和故障模式与后果分析法对其进行可靠性评估.通过对系统进行定义及对系统电压等级的划分,建立故障模式和后果分析表格及供电系统的故障树模型.在此基础上,求取故障树的最小割集,并利用自主开发的可靠性分析软件对3种供电情况进行可靠性评估.最后与实际工程相比较,验证了该可靠性分析方法的有效性和实用性.

  5. Reliability of Power Units in Poland and the World

    Józef Paska


    Full Text Available One of a power system’s subsystems is the generation subsystem consisting of power units, the reliability of which to a large extent determines the reliability of the power system and electricity supply to consumers. This paper presents definitions of the basic indices of power unit reliability used in Poland and in the world. They are compared and analysed on the basis of data published by the Energy Market Agency (Poland, NERC (North American Electric Reliability Corporation – USA, and WEC (World Energy Council. Deficiencies and the lack of a unified national system for collecting and processing electric power equipment unavailability data are also indicated.

  6. Efficient power supply in all weather conditions. Space satellite monitoring ensures reliable, low-cost power supply; Effiziente Stromversorgung trotz Wetterkapriolen. Dank Waechter aus dem All noch sicherere und guenstigere Stromversorgung



    Weather conditions are an important influencing factor in power generation, distribution and consumption. Long-distance power suppliers like the Nordostschweizerische Kraftwerke (NOK) therefore keep an eye on the weather. Satellites provide valuabe information that is tailored to the specific requirements of the power industry. [Deutsch] Die Witterung zaehlt noch immer zu den wichtigsten Einflussfaktoren bei der Produktion, der Verteilung und beim Verbrauch von Strom. Es liegt deshalb auf der Hand, dass grosse Ueberlandwerke, wie die Nordostschweizerische Kraftwerke (NOK), ein wachsames Auge auf das Wettergeschehen richten. Seit kurzem liefern ihnen Wettersatelliten wertvolle Entscheidungshilfen, die auf die besonderen Anforderungen der Stromproduktion zugeschnitten sind. (orig.)

  7. Power Quality and Reliability Project

    Attia, John O.


    One area where universities and industry can link is in the area of power systems reliability and quality - key concepts in the commercial, industrial and public sector engineering environments. Prairie View A&M University (PVAMU) has established a collaborative relationship with the University of'Texas at Arlington (UTA), NASA/Johnson Space Center (JSC), and EP&C Engineering and Technology Group (EP&C) a small disadvantage business that specializes in power quality and engineering services. The primary goal of this collaboration is to facilitate the development and implementation of a Strategic Integrated power/Systems Reliability and Curriculum Enhancement Program. The objectives of first phase of this work are: (a) to develop a course in power quality and reliability, (b) to use the campus of Prairie View A&M University as a laboratory for the study of systems reliability and quality issues, (c) to provide students with NASA/EPC shadowing and Internship experience. In this work, a course, titled "Reliability Analysis of Electrical Facilities" was developed and taught for two semesters. About thirty seven has benefited directly from this course. A laboratory accompanying the course was also developed. Four facilities at Prairie View A&M University were surveyed. Some tests that were performed are (i) earth-ground testing, (ii) voltage, amperage and harmonics of various panels in the buildings, (iii) checking the wire sizes to see if they were the right size for the load that they were carrying, (iv) vibration tests to test the status of the engines or chillers and water pumps, (v) infrared testing to the test arcing or misfiring of electrical or mechanical systems.

  8. Reliability Analyses of Transmission and Substation Facilities and Electricity Supply to Urban Consumers in 2007


    @@ Renabilities of transmission and substation facilities with voltaelevel of 220kV or above In 2007,there were totally 356 power supply enterprises,including 28 EHV transmission and substation enterprises,and 245 power generation enterprises submitting reliability performances of electric facilities at a voltage level of 220 kV or above to the Electric Power Reliability Management Center.The reliability indices of transmission and substation facilities in 2007 and 2006 are shown in Table 1.

  9. 47 CFR 80.1015 - Power supply.


    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Power supply. 80.1015 Section 80.1015... MARITIME SERVICES Radiotelephone Installations Required by the Bridge-to-Bridge Act § 80.1015 Power supply. (a) There must be readily available for use under normal load conditions, a power supply...

  10. EU ENERGY STAR Certified Uninterruptible Power Supplies

    Certified models meet all ENERGY STAR requirements as listed in the Version 1.0 ENERGY STAR Program Requirements for Uninterruptible Power Supplies that are effective as of August 1, 2012. A detailed listing of key efficiency criteria are available at

  11. ENERGY STAR Certified Uninterruptible Power Supplies

    Certified models meet all ENERGY STAR requirements as listed in the Version 1.0 ENERGY STAR Program Requirements for Uninterruptible Power Supplies that are effective as of August 1, 2012. A detailed listing of key efficiency criteria are available at

  12. Research of reliability prediction and modeling for traction power supply syste m%牵引供电系统可靠性预测及建模方法研究

    赵峰; 张庆平; 王思华


    Byusing unbiased GM(1,1)model to predict the long -term failure data of its associated equipment, and increasing the sample of the required data for modeling.To solve the reliability of traction power supply sys-tem modeling with less failure data,which leads to the possibility of modeling accuracy is low and modeling of failure is high.In this paper,by using a fitting method based on particle swarm optimization(PSO),a reliability modeling method of traction power supply system based on Weibull distribution model was proposed,and the reli-ability models of all components of traction power supply system were established,it is made sure of that the fit-ting precision of fault data is bigger improved.The fault tree analysis(FTA)model of traction substation and cat-enary system were established by minimal cut sets,based on these,the reliability model of traction power supply system is finished,then reliability and the average useful time of system are calculated,Finally,the main factors affecting traction power supply system reliability was calculated by establishing the gray relational analysis model. The results indicate that the reliability of the system depends on contract line in a large extent.%基于采用无偏 GM(1,1)模型预测其相关设备中长期的故障数据,增大了建模所需的数据样本量,能解决牵引供电系统可靠性建模由于故障数据较少,导致建模的精度不高且建模失败的可能性大的问题,提出基于粒子群算法的智能拟合方法。以威布尔分布模型为基础,建立牵引供电系统各关键设备可靠性分析的数学模型。计算得到用最小割集表示的牵引变电所和接触网故障树模型,综合分析得出牵引供电系统整体的可靠性模型,并计算系统整体的可靠度和平均使用寿命,通过建立灰色关联分析模型,计算得出接触线是影响牵引供电系统整体可靠性的关键设备。

  13. Design of intrinsically safe power supply

    LI Rui-jin; JIN Lin


    Aiming to make a high power direct current supply safely used in coal mine production,this paper made a deep research on characteristics of intrinsically safe power supply,using the mathematical model established according to coal mine intrinsic safety standards.It provides theory support for the application of high power intrinsically safe power supply.The released energy of output short circuit of switch power supply,and the close related factors that influence the biggest output short-circuit spark discharge energy are the theoretical basis of the power supply.It is shown how to make a high power intrinsically safe power supply using the calculated values in the mathematical model,and take values from intrinsically safe requirements parameters scope,then this theoretical calculation value can be developed as the ultimate basis for research of the power supply.It gets the identification method of intrinsically safe from mathematics model of intrinsically safe power supply characteristics study,which solves the problem of theory and application of designing different power intrinsically safe power supply,and designs a kind of high power intrinsically safe power supply through this method.

  14. Alternating Current Uninterrupted Power Supply System with High Reliability%高可靠性交流不间断供电系统

    匡莉娟; 施洪昌


    为提高供电系统的工作可靠性,介绍了一种具有高可靠性的交流不问断供电系统的设计方法.该系统是由UPS (uninterrupted power supply)并联模块、电子切换开关、电子稳压器等组成.UPS的并联运行是提高电源系统运行可靠性和扩大供电容量的重要手段.由交流稳压器作为UPS的后备电源,提高了系统的可靠性.电子开关保证系统的在线零切换,真正做到对负载供电的不间断.组成系统的模块都可以进行在线维修和更换,可以提高系统的MTBF (mean time between failures),进一步提高系统的可靠性.

  15. Bayesian Algorithms for Calculating Symbolic Rates of the Unreliability and Reliability of the Electric Supply

    Włodzimierz Korniluk


    Full Text Available The report presents the use of Bayesian networks in the calculation of symbolic indicators of reliability and unreliability of the electric power supplying load point. The calculation of indicators of reliability is determined by the analytical dependencies. These dependencies are used to estimate: probability of up or down state of power system components supplying the load point; total probability distribution; conditional probabilities of the state power or lack of power appearance; the intensity of current interruptions and the average time of their duration; contributions of individual power system components in the service reliability. This report describes how to obtain these analytical dependencies, using the ultimate application for symbolic computations Mathematica (ver. 8. In this paper we will discuss the results of the symbolic computations for selected supply power system and methods for reducing the duration of symbolic computations of indicators for multiple-compound electrical power systems.

  16. Progress of Power Supply System in 2003

    GaoDaqing; ZhouZhongzu; WuRong; ChenYouxin


    CSR power supply system made a great progress in 2003. All power supplies for CSRm E-cooler have been accepted and put into operation since Feb. 2003. And we are preparing to test power supplies of CSRe cooler 31 sets pulsed convertor for CSRm quadruple magnet arrived in IMP. But their output current must be increased from 590 A to 700 A, because of higher beam energy. 12 of them can fit the new request, but the others have to be redesigned and reproduced. The dipole power supply was assembled in plant and by using the power supply was some experiment made. The first test results was excited. Now this device has been installed in IMP and connected with the dipole magnet. We invited a public bidding for RIBLL2 and CSRe power supplies last September. Two companies provided 128 power supplies, which will be delivered to IMP before June 2004.

  17. Grid Connected Power Supplies for Particle Accelerator Magnets

    Nielsen, Rasmus Ørndrup

    and smaller converter size. A high efficiency converter based on Silicon Carbide switching devices is also presented exhibiting above 96 % efficiency for the entire power range. Finally reliability issues are considered as the reliability of a particle accelerator supply is of utmost importance. Particle...

  18. 基于灰色理论和PSO的牵引供电系统可靠性研究%Research on the Reliability of Traction Power Supply System Based on Gray Theory and PSO

    张庆平; 赵峰; 王思华


    采用灰色GM(1,1)模型预测其相关设备中长期的故障数据,增大建模所需数据样本量,提出以威布尔分布模型为基础,基于粒子群算法的智能拟合方法,建立牵引供电系统各设备可靠性分析的数学模型,所建模型全部通过拟合优度K-S检验,证明该方法十分适合于牵引供电系统设备的可靠性建模。运用BDD算法得到用最小割集表示的牵引变电所和接触网故障树模型,综合得到牵引供电系统整体的可靠性模型,并计算出系统的可靠度和平均使用寿命。最后分析可知接触网的可靠性在很大程度上决定了牵引供电系统整体的可靠性,其分析结果为牵引供电系统以后的维护工作提供了理论依据。%In order to increase the amount of sample data required to establish models and predict the failure-rate data of the relevant equipment in medium and long terms, gray GM(1,1) model is used based on particle swarm optimization(PSO) and a reliability modeling method of traction power supply system based on Weibull distribution model is proposed. Such models so established satisfy K-S goodness of fit test, and justify the feasibility of the method. The fault tree analysis ( FTA ) model of traction substation and catenary system in terms of minimum cut set is established by using binary decision diagram ( BBD) algorithm, the reliability model of TPSS is obtained, and the reliability and the average useful time of system are calculated. The results of analysis demonstrate that the reliability of the traction power supply system as a whole depends largely on the reliability of catenary system, and provides a theoretical basis for future maintenance for traction power supply system.

  19. Ultracapacitor-Based Uninterrupted Power Supply System

    Eichenberg, Dennis J.


    The ultracapacitor-based uninterrupted power supply (UPS) system enhances system reliability; reduces life-of-system, maintenance, and downtime costs; and greatly reduces environmental impact when compared to conventional UPS energy storage systems. This design provides power when required and absorbs power when required to smooth the system load and also has excellent low-temperature performance. The UPS used during hardware tests at Glenn is an efficient, compact, maintenance-free, rack-mount, pure sine-wave inverter unit. The UPS provides a continuous output power up to 1,700 W with a surge rating of 1,870 W for up to one minute at a nominal output voltage of 115 VAC. The ultracapacitor energy storage system tested in conjunction with the UPS is rated at 5.8 F. This is a bank of ten symmetric ultracapacitor modules. Each module is actively balanced using a linear voltage balancing technique in which the cell-to-cell leakage is dependent upon the imbalance of the individual cells. The ultracapacitors are charged by a DC power supply, which can provide up to 300 VDC at 4 A. A constant-voltage, constant-current power supply was selected for this application. The long life of ultracapacitors greatly enhances system reliability, which is significant in critical applications such as medical power systems and space power systems. The energy storage system can usually last longer than the application, given its 20-year life span. This means that the ultracapacitors will probably never need to be replaced and disposed of, whereas batteries require frequent replacement and disposal. The charge-discharge efficiency of rechargeable batteries is approximately 50 percent, and after some hundreds of charges and discharges, they must be replaced. The charge-discharge efficiency of ultracapacitors exceeds 90 percent, and can accept more than a million charges and discharges. Thus, there is a significant energy savings through the efficiency improvement, and there is far less

  20. Novel supplies for powering a sueprconducting magnet

    Shevchenko, O.A.; Krooshoop, H.J.G.; Kate, ten H.H.J.; Grunblatt, G.; Shevchenko, A.A.; Kolesnitchenko, A.F.; Sidorenko, V.D.; Grytsina, A.E.; Lysenko, V.; Scherbakov, V.I.; Anashkin, O.; Keylin, V.E.


    A family of new supplies for powering superconducting magnets was developed in our institutes. As an example, two supplies are described in the paper. One of the supplies uses superconducting, another-semiconductor-based repetitive switches. Both supplies are able to generate 1 Volt at the high-curr

  1. Advanced Accessory Power Supply Topologies

    Marlino, L.D.


    This Cooperative Research and Development Agreement (CRADA) began December 8, 2000 and ended September 30, 2009. The total funding provided by the Participant (General Motors Advanced Technology Vehicles [GM]) during the course of the CRADA totaled $1.2M enabling the Contractor (UT-Battelle, LLC [Oak Ridge National Laboratory, a.k.a. ORNL]) to contribute significantly to the joint project. The initial task was to work with GM on the feasibility of developing their conceptual approach of modifying major components of the existing traction inverter/drive to develop low cost, robust, accessory power. Two alternate methods for implementation were suggested by ORNL and both were proven successful through simulations and then extensive testing of prototypes designed and fabricated during the project. This validated the GM overall concept. Moreover, three joint U.S. patents were issued and subsequently licensed by GM. After successfully fulfilling the initial objective, the direction and duration of the CRADA was modified and GM provided funding for two additional tasks. The first new task was to provide the basic development for implementing a cascaded inverter technology into hybrid vehicles (including plug-in hybrid, fuel cell, and electric). The second new task was to continue the basic development for implementing inverter and converter topologies and new technology assessments for hybrid vehicle applications. Additionally, this task was to address the use of high temperature components in drive systems. Under this CRADA, ORNL conducted further research based on GM’s idea of using the motor magnetic core and windings to produce bidirectional accessory power supply that is nongalvanically coupled to the terminals of the high voltage dc-link battery of hybrid vehicles. In order not to interfere with the motor’s torque, ORNL suggested to use the zero-sequence, highfrequency harmonics carried by the main fundamental motor current for producing the accessory power

  2. 量化分析配电自动化对提高供电可靠性的作用%Quantitative Analysis of Distribution Automation to Improve Power Supply Reliability



      通过统计厦门配电自动化系统实用化以来的系统运行数据,计算遥控操作和故障处理两方面减少的停电时户数,进而得出配电自动化提高供电可靠性的量化数值,为评估配电自动化建设的成效提供参考。%  Based on the statistical analysis of the distribution system operation data collected since the distribution system was put into operation in Xiamen power grid, the paper calculates the number of consumer outages as reduced attributed to remote control and fault handling, and obtains the increased power supply reliability value of distribution automation system and provides references for assessing the effectiveness of distribution automation system construction.

  3. Low Voltage Power Supply Incorporating Ceramic Transformer

    Imori, M


    A low voltage power supply provides the regulated output voltage of 1 V from the supply voltage around 48 V. The low voltage power supply incorporates a ceramic transformer which utilizes piezoelectric effect to convert voltage. The ceramic transformer isolates the secondary from the primary, thus providing the ground isolation between the supply and the output voltages. The ceramic transformer takes the place of the conventional magnetic transformer. The ceramic transformer is constructed from a ceramic bar and does not include any magnetic material. So the low voltage power supply can operate under a magnetic field. The output voltage is stabilized by feedback. A feedback loop consists of an error amplifier, a voltage controlled oscillator and a driver circuit. The amplitude ratio of the transformer has dependence on the frequency, which is utilized to stabilize the output voltage. The low voltage power supply is investigated on the analogy of the high voltage power supply similarly incorporating the cerami...

  4. 49 CFR 236.516 - Power supply.


    ... 49 Transportation 4 2010-10-01 2010-10-01 false Power supply. 236.516 Section 236.516..., Train Control and Cab Signal Systems Standards § 236.516 Power supply. Automatic cab signal, train stop, or train control device hereafter installed shall operate from a separate or isolated power...

  5. Distribution Reliability of the Energy Supply Chain

    Hidayat Rachmad


    Full Text Available Reliability of an oil fuel distribution system can be achieved by considering multiple attributes. Load-point indicators consisted of the frequency of failures, average duration of an outage and average annual outage time. Indicators of system performance were SAIFI and SAIDI and the method of the study was the Learning Vector Quantization (LVQ. Decisions were made by considering the multi-attribute oil fuel distribution system to determine high reliability, which was simulated on the agent. The use of agents in the simulation to determine the oil fuel distribution system reliability helped visualize the oil fuel distribution in meeting the quality of fuels received by consumers and made it easier to learn the problems faced by oil fuel distribution.

  6. Simplified design of switching power supplies

    Lenk, John


    * Describes the operation of each circuit in detail * Examines a wide selection of external components that modify the IC package characteristics * Provides hands-on, essential information for designing a switching power supply Simplified Design of Switching Power Supplies is an all-inclusive, one-stop guide to switching power-supply design. Step-by-step instructions and diagrams render this book essential for the student and the experimenter, as well as the design professional. Simplified Design of Switching Power Supplies concentrates on the use of IC regulators. All popular forms of swit

  7. Distributed Energy Resources, Power Quality and Reliability - Background

    Schienbein, Lawrence A.; DeSteese, John G.


    Power quality [PQ] and power reliability [PR] gained importance in the industrialized world as the pace of installation of sensitive appliances and other electrical loads by utility customers accelerated, beginning in the mid 1980s. Utility-grid-connected customers rapidly discovered that this equipment was increasingly sensitive to various abnormalities in the electricity supply.

  8. Simplified design of switching power supplies

    Lenk, John


    Simplified Design of Switching Power Supplies is an all-inclusive, one-stop guide to switching power-supply design. Step-by-step instructions and diagrams render this book essential for the student and the experimenter, as well as the design professional.Simplified Design of Switching Power Supplies concentrates on the use of IC regulators. All popular forms of switching supplies, including DC-DC converters, inverters, buck, boost, buck-boost, pulse frequency modulation, pulse width modulation, current-mode control and pulse skipping, are described in detail. The design examples may

  9. Design for Reliability of Power Electronic Systems

    Wang, Huai; Ma, Ke; Blaabjerg, Frede


    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...... 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....

  10. 46 CFR 169.688 - Power supply.


    ... 46 Shipping 7 2010-10-01 2010-10-01 false Power supply. 169.688 Section 169.688 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Electrical Installations on Vessels of 100 Gross Tons and Over § 169.688 Power supply. (a)...

  11. High Power Amplifier and Power Supply

    Duong, Johnny; Stride, Scot; Harvey, Wayne; Haque, Inam; Packard, Newton; Ng, Quintin; Ispirian, Julie Y.; Waian, Christopher; Janes, Drew


    A document discusses the creation of a high-voltage power supply (HVPS) that is able to contain voltages up to -20 kV, keep electrical field strengths to below 200 V/mil (approximately equal to 7.87 kV/mm), and can provide a 200-nanosecond rise/fall time focus modulator swinging between cathode potential of 16.3 kV and -19.3 kV. This HVPS can protect the 95-GHz, pulsed extended interaction klystron (EIK) from arcs/discharges from all sources, including those from within the EIK fs vacuum envelope. This innovation has a multi-winding pulse transformer design, which uses new winding techniques to provide the same delays and rise/fall times (less than 10 nanoseconds) at different potential levels ranging from -20 kV to -16 kV. Another feature involves a high-voltage printed-wiring board that was corona-free at -20 kV DC with a 3- kV AC swing. The corona-free multilayer high-voltage board is used to simulate fields of less than 200 V/mil (approximately equal to 7.87 kV/mm) at 20 kV DC. Drive techniques for the modulator FETs (field-effect transistors) (four to 10 in a series) were created to change states (3,000-V swing) without abrupt steps, while still maintaining required delays and transition times. The packing scheme includes a potting mold to house a ten-stage modulator in the space that, in the past, only housed a four-stage modulator. Problems keeping heat down were solved using aluminum oxide substrate in the high-voltage section to limit temperature rise to less than 10 while withstanding -20 kV DC voltage and remaining corona-free.

  12. Reliability provision for supplies plan in logistic chains

    Vladimir Tkach


    Full Text Available Background: The economics globalization leaded to the growth of the number of international and global supply chains, possessing potentially vulnerable places due to the reason of their high duration and existence of cultural and other barriers between the participants of supply chains. Intensification of international competition, in its turn, conditioned the increase of supply intensity, reduction of logistic chains links number and decrease in them of material reserves. Potential instability and unreliability of supply chains as well as their vulnerability also increased. Methods: The basic aspects of supply reliability provision in logistic networks based on planning decisions were discussed. Results and conclusions: There is grounded the necessity for accounting in supply plans of integral qualities of logistic systems, their functioning modes and life cycles of their elements relations. There is suggested the instrument for planning of maneuvers in supply networks in conditions of indeterminacy of future parameters of demand and resources deficit.

  13. PEP-II Large Power Supplies Rebuild Program at SLAC

    Bellomo, P.; Lipari, J.J.; de Lira, A.C.; Rafael, F.S.; /SLAC


    Seven large power supplies (LGPS) with output ratings from 72kW to 270kW power PEP-II quad magnets in the electron-positron collider region. These supplies have posed serious maintenance and reliability problems since they were installed in 1997, resulting in loss of accelerator availability. A redesign/rebuild program was undertaken by the SLAC Power Conversion Department. During the 2004 summer shutdown all the control circuits in these supplies were redesigned and replaced. A new PWM control board, programmable logic controller, and touch panel have been installed to improve LGPS reliability, and to make troubleshooting easier. In this paper we present the details of this rebuilding program and results.

  14. Intelligent Vehicle Electrical Power Supply System with Central Coordinated Protection

    YANG Diange; KONG Weiwei; LI Bing; LIAN Xiaomin


    The current research of vehicle electrical power supply system mainly focuses on electric vehicles (EV) and hybrid electric vehicles (HEV). The vehicle electrical power supply system used in traditional fuel vehicles is rather simple and imperfect;electrical/electronic devices (EEDs) applied in vehicles are usually directly connected with the vehicle’s battery. With increasing numbers of EEDs being applied in traditional fuel vehicles, vehicle electrical power supply systems should be optimized and improved so that they can work more safely and more effectively. In this paper, a new vehicle electrical power supply system for traditional fuel vehicles, which accounts for all electrical/electronic devices and complex work conditions, is proposed based on a smart electrical/electronic device (SEED) system. Working as an independent intelligent electrical power supply network, the proposed system is isolated from the electrical control module and communication network, and access to the vehicle system is made through a bus interface. This results in a clean controller power supply with no electromagnetic interference. A new practical battery state of charge (SoC) estimation method is also proposed to achieve more accurate SoC estimation for lead-acid batteries in traditional fuel vehicles so that the intelligent power system can monitor the status of the battery for an over-current state in each power channel. Optimized protection methods are also used to ensure power supply safety. Experiments and tests on a traditional fuel vehicle are performed, and the results reveal that the battery SoC is calculated quickly and sufficiently accurately for battery over-discharge protection. Over-current protection is achieved, and the entire vehicle’s power utilization is optimized. For traditional fuel vehicles, the proposed vehicle electrical power supply system is comprehensive and has a unified system architecture, enhancing system reliability and security.

  15. Intelligent vehicle electrical power supply system with central coordinated protection

    Yang, Diange; Kong, Weiwei; Li, Bing; Lian, Xiaomin


    The current research of vehicle electrical power supply system mainly focuses on electric vehicles (EV) and hybrid electric vehicles (HEV). The vehicle electrical power supply system used in traditional fuel vehicles is rather simple and imperfect; electrical/electronic devices (EEDs) applied in vehicles are usually directly connected with the vehicle's battery. With increasing numbers of EEDs being applied in traditional fuel vehicles, vehicle electrical power supply systems should be optimized and improved so that they can work more safely and more effectively. In this paper, a new vehicle electrical power supply system for traditional fuel vehicles, which accounts for all electrical/electronic devices and complex work conditions, is proposed based on a smart electrical/electronic device (SEED) system. Working as an independent intelligent electrical power supply network, the proposed system is isolated from the electrical control module and communication network, and access to the vehicle system is made through a bus interface. This results in a clean controller power supply with no electromagnetic interference. A new practical battery state of charge (SoC) estimation method is also proposed to achieve more accurate SoC estimation for lead-acid batteries in traditional fuel vehicles so that the intelligent power system can monitor the status of the battery for an over-current state in each power channel. Optimized protection methods are also used to ensure power supply safety. Experiments and tests on a traditional fuel vehicle are performed, and the results reveal that the battery SoC is calculated quickly and sufficiently accurately for battery over-discharge protection. Over-current protection is achieved, and the entire vehicle's power utilization is optimized. For traditional fuel vehicles, the proposed vehicle electrical power supply system is comprehensive and has a unified system architecture, enhancing system reliability and security.

  16. Wireless Power Transmission for Power Supply: State of Art


    The wireless power supply is motivated by simple and comfortable use of many small electric appliances with low power input. This paper reviews the concepts which are suitable for wireless power transmission with respect to power supply of such appliances in small areas. The categorization of the concepts is made. The efficiency of the concepts is discussed on general base. The reference levels for exposure to electric and magnetic fields are mentioned, and maximal power delivered to an appli...

  17. Active Rectifier for Uninterruptable Power Supply

    Stepanov, Andrew; Bogdans, Valdis; Suskis, Pavel; Galkin, Ilya


    The paper contains analysis of power factor correction circuits that is made in the context of elaboration of uninterruptable power supply system. Various correctors have been estimated analytically, by means of simulation and experimentally. The most significant attention has been paid to the efficiency of the analyzed converters and their compatibility with modular approach to development of power converters.

  18. Digitally Controlled High Availability Power Supply

    MacNair, David; /SLAC


    This paper will report on the test results of a prototype 1320 watt power module for a high availability power supply. The module will allow parallel operation for N+1 redundancy with hot swap capability. The two quadrant output of each module allows pairs of modules to provide a 4 quadrant (bipolar) operation. Each module employs a novel 4 FET buck regulator arranged in a bridge configuration. Each side of the bridge alternately conducts through a small saturable ferrite that limits the reverse current in the FET body diode during turn off. This allows hard switching of the FETs with low switching losses. The module is designed with over-rated components to provide high reliability and better then 97% efficiency at full load. The modules use a Microchip DSP for control, monitoring, and fault detection. The switching FETS are driven by PWM modules in the DSP at 60 KHz. A Dual CAN bus interface provides for low cost redundant control paths. The DSP will also provide current sharing between modules, synchronized switching, and soft start up for hot swapping. The input and output of each module have low resistance FETs to allow hot swapping and isolation of faulted units.

  19. Design of ITER NBI power supply system

    Watanabe, Kazuhiro; Ohara, Yoshihiro; Okumura, Yoshikazu [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Higa, Osamu; Kawashima, Syuichi; Ono, Youichi; Tanaka, Masanobu; Yasutomi, Sei


    Power supply system for the ITER neutral beam injector (NBI) whose total injection power is 1 MeV, 50 MW from three modules, has been designed. The power supply system consists of a source power supply for negative ion production/extraction and a DC 1 MV, 45 A power supply for negative ion acceleration. An inverter controlled multi-transformer/rectifier system has been adopted to the acceleration power supply. An inverter frequency of 150 Hz was selected to satisfy required specifications which are rise time of <100 ms, voltage ripple of <10% peak to peak and cut off speed of <200{mu}s. It was confirmed that the rise time, the ripple and the cut off speed is about 50 ms, 7% and <200{mu}s respectively by computation. It was also confirmed that a surge current and an energy input to the ion source at the breakdown can be suppressed lower than 3 kA and 10 J, which are considered to be lower than allowable values. A 1 MV transmission line has been designed from a view point of electric field on the inner conductors and grounded conductor. The results from the design study indicate that all the required specification to the power supply system can be satisfied and that R and D on the transmission line is one of the most important subjects. (author)

  20. The investigation of supply chain's reliability measure: a case study

    Taghizadeh, Houshang; Hafezi, Ehsan


    In this paper, using supply chain operational reference, the reliability evaluation of available relationships in supply chain is investigated. For this purpose, in the first step, the chain under investigation is divided into several stages including first and second suppliers, initial and final customers, and the producing company. Based on the formed relationships between these stages, the supply chain system is then broken down into different subsystem parts. The formed relationships between the stages are based on the transportation of the orders between stages. Paying attention to the system elements' location, which can be in one of the five forms of series namely parallel, series/parallel, parallel/series, or their combinations, we determine the structure of relationships in the divided subsystems. According to reliability evaluation scales on the three levels of supply chain, the reliability of each chain is then calculated. Finally, using the formulas of calculating the reliability in combined systems, the reliability of each system and ultimately the whole system is investigated.

  1. ENERGY STAR Certified Uninterruptible Power Supplies

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 1.0 ENERGY STAR Program Requirements for Uninterruptible Power Supplies that are...

  2. Innovative use of power integrated modules for DC power supplies

    Ørndrup Nielsen, Rasmus; Elkiær, Alexander; Munk-Nielsen, Stig;


    In this article several innovative ways of utilizing Power Integrated Modules (PIM) as switching device in a DC power supply are presented. PIM have advantages in compactness of design, cost and fast prototype due to easier PCB layout. A PIM converter topology is chosen and designed resulting...... in an experimental setup. Results from the setup are presented showing the feasibility of using a PIM module as almost all power semiconductors in a DC power supply....

  3. Innovations in power systems reliability

    Santora, Albert H; Vaccaro, Alfredo


    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.

  4. On reliability optimization for power generation systems


    The reliability level of a power generation system is an important problem which is concerned by both electricity producers and electricity consumers. Why? It is known that the high reliability level may result in additional utility cost, and the low reliability level may result in additional consumer's cost, so the optimum reliability level should be determined such that the total cost can reach its minimum. Four optimization models for power generation system reliability are constructed, and the proven efficient solutions for these models are also given.

  5. Reliability Evaluation of Microgrid Power Supply in Emergency Non-scheduled Isolated Mode%非计划孤岛下的微电网供电可靠性评估

    解翔; 袁越; 邹文仲; 李振杰


    As a new structure of the distribution network,the microgrid can switch from grid-connected mode to grid-off mode flexibly.This feature can make consumers in microgrid get better power supply and guarantee the power supply for important loads against power off in extreme conditions such as earthquakes,snowstorms and the collapse of the large grid.Fault tree analysis is used to develop the reliability model for the microgrid in grid-off mode and calculate the failure rate in fixed time with Monte Carlo simulation method.In this way,the uninterruptible power system(UPS) capacity of microgrid in extreme conditions is assessed.Take an actual microgrid system for an example,the impact of the various components of microgrid on the UPS capacity is analyzed,which is helpful to making some recommendations on the microgrid construction.%微电网作为一种新型配电网结构,其最大的特点就在于可以在并网运行与离网运行之间灵活切换。这一特点使得微电网用户可以获得更高质量的电能供应,并且在地震、雪灾、大电网崩溃等极端条件下保证重要负荷的电力供应。文中应用故障树图法建立微电网离网运行模式下的可靠性模型,并用蒙特卡洛模拟法计算固定时间内微电网离网运行故障率,评估微电网在极端条件下的持续供电能力。以实际微电网系统为例,分析微电网各元件对其离网持续运行能力的影响程度,为微电网的架设提供了建议。

  6. Improvements in electric power supply in coal mines

    Minovskii, Yu.P.; Nabokov, Eh.P.; Savel' ev, G.P.


    Reviews measures taken by major coal producing countries to increase output levels. Discusses research carried out into advance design of equipment in FRG, UK, USA and France and proposes establishment of central automatic control of electric power supply system in Soviet mines, improvement in underground power supply equipment, increase in reliability, stabilization of standby capacity in low voltage circuits, maintenance-free electrical equipment, and efficient spare part storage in underground workings. States that introduction of the proposed system (details are given) will ensure that Soviet mines will eventually reach the development level of foreign mines. 2 refs.

  7. A number of upgrades on RHIC power supply system

    Mi, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Drozd, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Nolan, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Orsatti, F. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Heppener, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Di Lieto, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Schultheiss, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Samms, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Zapasek, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Sandberg, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.


    This year marks the 15th run for the Relativistic Heavy Ion Collider (RHIC). Operation of a reliable superconducting magnet power supply system is a key factor of an accelerator’s performance. Over the past 15 years, the RHIC power supply group has made many improvements to increase the machine availability and reduce failures. During these past 15 years of operating RHIC a lot of problems have been solved or addressed. In this paper some of the essential upgrades/improvements are discussed.

  8. 电网末端电压合格率和供电可靠率在线监测实现方法%Study on the on-line monitoring technology of power network terminal voltage qualification rate and power supply reliability

    余涛; 黄申茂; 李铭


    In this paper, the on⁃line monitoring technology based on intelligent electric energy meter is studied to monitor the voltage qualification rate and the reliability of power supply, and realize the collection and analysis of the terminal voltage qualification rate and the power supply reliability. The research results of this paper make up the shortage of monitoring statistics on the two rates to monitor the end of the power supply in the prior art. The technology provides an effective information support for the power supply de⁃partment to improve the quality of the end of the power grid. The technology improves in formation and smart level of energy quantity in order to satisfy the customers’power requirement.%探讨一种基于智能电能表完成电压合格率和供电可靠率的在线监测技术。该技术实现了电网末端电压合格率和供电可靠率的采集与分析,弥补了现有技术中对电网末端电压合格率和供电可靠率监测统计的不足,为供电部门改善电网末端供电质量提供有效的信息支撑,提高电能质量管理的信息化与智能化水平,以更好地满足客户用电需求。

  9. Thermal Impact Analysis of Circulating Current in High Power Modular Online Uninterruptible Power Supplies Application

    Zhang, Chi; Guerrero, Josep M.; Vasquez, Juan Carlos


    In a modular uninterruptible power supplies (UPS), each DC/AC module was designed to work in a circular way considering the reliability and power stress issues of the whole system. Thus unsynchronized PWMs will occur if any of the DC/AC modules is plugged in or out of the system at any time...

  10. The Economics of Groundwater Replenishment for Reliable Urban Water Supply

    Lei Gao


    Full Text Available This paper explores the potential economic benefits of water banking in aquifers to meet drought and emergency supplies for cities where the population is growing and changing climate has reduced the availability of water. A simplified case study based on the city of Perth, Australia was used to estimate the savings that could be achieved by water banking. Scenarios for investment in seawater desalination plants and groundwater replenishment were considered over a 20 year period of growing demand, using a Monte Carlo analysis that embedded the Markov model. An optimisation algorithm identified the minimum cost solutions that met specified criteria for supply reliability. The impact of depreciation of recharge credits was explored. The results revealed savings of more than A$1B (~US$1B or 37% to 33% of supply augmentation costs by including water banking in aquifers for 95% and 99.5% reliability of supply respectively. When the hypothetically assumed recharge credit depreciation rate was increased from 1% p.a. to 10% p.a. savings were still 33% to 31% for the same reliabilities. These preliminary results show that water banking in aquifers has potential to offer a highly attractive solution for efficiently increasing the security of urban water supplies where aquifers are suitable.

  11. Power grid reliability and security

    Bose, Anjan [Washington State Univ., Pullman, WA (United States); Venkatasubramanian, Vaithianathan [Washington State Univ., Pullman, WA (United States); Hauser, Carl [Washington State Univ., Pullman, WA (United States); Bakken, David [Washington State Univ., Pullman, WA (United States); Anderson, David [Washington State Univ., Pullman, WA (United States); Zhao, Chuanlin [Washington State Univ., Pullman, WA (United States); Liu, Dong [Washington State Univ., Pullman, WA (United States); Yang, Tao [Washington State Univ., Pullman, WA (United States); Meng, Ming [Washington State Univ., Pullman, WA (United States); Zhang, Lin [Washington State Univ., Pullman, WA (United States); Ning, Jiawei [Washington State Univ., Pullman, WA (United States); Tashman, Zaid [Washington State Univ., Pullman, WA (United States)


    This project has led to the development of a real-time simulation platform for electric power grids called Grid Simulator or GridSim for simulating the dynamic and information network interactions of large- scale power systems. The platform consists of physical models of power system components including synchronous generators, loads and control, which are simulated using a modified commercial power simulator namely Transient Stability Analysis Tool (TSAT) [1] together with data cleanup components, as well as an emulated substation level and wide-area power analysis components. The platform also includes realistic representations of communication network middleware that can emulate the real-time information flow back and forth between substations and control centers in wide-area power systems. The platform has been validated on a realistic 6000-bus model of the western American power system. The simulator GridSim developed in this project is the first of its kind in its ability to simulate real-time response of large-scale power grids, and serves as a cost effective real-time stability and control simulation platform for power industry.


    Bose, Anjan; Venkatasubramanian, Vaithianathan; Hauser, Carl; Bakken, David; Anderson, David; Zhao, Chuanlin; Liu, Dong; Yang, Tao; Meng, Ming; Zhang, Lin; Ning, Jiawei; Tashman, Zaid


    This project has led to the development of a real-time simulation platform for electric power grids called Grid Simulator or GridSim for simulating the dynamic and information network interactions of large- scale power systems. The platform consists of physical models of power system components including synchronous generators, loads and control, which are simulated using a modified commercial power simulator namely Transient Stability Analysis Tool (TSAT) [1] together with data cleanup components, as well as an emulated substation level and wide-area power analysis components. The platform also includes realistic representations of communication network middleware that can emulate the real-time information flow back and forth between substations and control centers in wide-area power systems. The platform has been validated on a realistic 6000-bus model of the western American power system. The simulator GridSim developed in this project is the first of its kind in its ability to simulate real-time response of large-scale power grids, and serves as a cost effective real-time stability and control simulation platform for power industry.

  13. Innovative power supply concepts for DBD excilamps

    Piquet, Hubert; Bhosle, Sounil; Díez, Rafael; Toumi, Areski; Zissis, Georges


    Excimer and exciplex UV/VUV sources excited by Dielectric Barrier Discharges represent a promising technology for industrial applications where powerful and efficient UV sources are needed. According to previous work, the most suited power supply waveform for coaxial DBD Excilamps is a unipolar pulsed voltage excitation of some kilovolts at some hundred of kilohertz with a duty cycle around one percent. We present here new concepts for energy supplying of coaxial DBDs, based on the direct control of the current in the lamps. These concepts have been tested by means of simulation models developed in our department and the time evolution of the UV radiation is presented for various considered current waveforms. Based on these results, a power supply topology has been designed for an efficient power transfer to the Excilamp. It is based on a converter which controls the current flowing through the DBD. The results concerning the coupling of this converter with a DBD load are commented.

  14. Efficient chaotic based satellite power supply subsystem

    Ramos Turci, Luiz Felipe [Technological Institute of Aeronautics (ITA), Sao Jose dos Campos, SP (Brazil)], E-mail:; Macau, Elbert E.N. [National Institute of Space Research (Inpe), Sao Jose dos Campos, SP (Brazil)], E-mail:; Yoneyama, Takashi [Technological Institute of Aeronautics (ITA), Sao Jose dos Campos, SP (Brazil)], E-mail:


    In this work, we investigate the use of the Dynamical System Theory to increase the efficiency of the satellite power supply subsystems. The core of a satellite power subsystem relies on its DC/DC converter. This is a very nonlinear system that presents a multitude of phenomena ranging from bifurcations, quasi-periodicity, chaos, coexistence of attractors, among others. The traditional power subsystem design techniques try to avoid these nonlinear phenomena so that it is possible to use linear system theory in small regions about the equilibrium points. Here, we show that more efficiency can be drawn from a power supply subsystem if the DC/DC converter operates in regions of high nonlinearity. In special, if it operates in a chaotic regime, is has an intrinsic sensitivity that can be exploited to efficiently drive the power subsystem over high ranges of power requests by using control of chaos techniques.

  15. Designing reliable supply chain network with disruption risk

    Ali Bozorgi Amiri


    Full Text Available Although supply chains disruptions rarely occur, their negative effects are prolonged and severe. In this paper, we propose a reliable capacitated supply chain network design (RSCND model by considering random disruptions in both distribution centers and suppliers. The proposed model determines the optimal location of distribution centers (DC with the highest reliability, the best plan to assign customers to opened DCs and assigns opened DCs to suitable suppliers with lowest transportation cost. In this study, random disruption occurs at the location, capacity of the distribution centers (DCs and suppliers. It is assumed that a disrupted DC and a disrupted supplier may lose a portion of their capacities, and the rest of the disrupted DC's demand can be supplied by other DCs. In addition, we consider shortage in DCs, which can occur in either normal or disruption conditions and DCs, can support each other in such circumstances. Unlike other studies in the extent of literature, we use new approach to model the reliability of DCs; we consider a range of reliability instead of using binary variables. In order to solve the proposed model for real-world instances, a Non-dominated Sorting Genetic Algorithm-II (NSGA-II is applied. Preliminary results of testing the proposed model of this paper on several problems with different sizes provide seem to be promising.


    Popescu V.S.


    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.

  17. Evolution of Very High Frequency Power Supplies

    Knott, Arnold; Andersen, Toke Meyer; Kamby, Peter


    in radio frequency transmission equipment helps to overcome those. However those circuits were not designed to meet the same requirements as power converters. This paper summarizes the contributions in recent years in application of very high frequency (VHF) technologies in power electronics, shows results......The ongoing demand for smaller and lighter power supplies is driving the motivation to increase the switching frequencies of power converters. Drastic increases however come along with new challenges, namely the increase of switching losses in all components. The application of power circuits used...

  18. Design for Reliability of Power Electronic Systems

    Wang, Huai; Ma, Ke; Blaabjerg, Frede


    availability, long lifetime, sufficient robustness, low maintenance cost and low cost of energy. However, the reliability predictions are still dominantly according to outdated models and terms, such as MIL-HDBK-217F handbook models, Mean-Time-To-Failure (MTTF), and Mean-Time-Between-Failures (MTBF......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...

  19. Reliability of power electronic converter systems

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


    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.

  20. Alternative power supply systems for remote industrial customers

    Kharlamova, N. V.; Khalyasmaa, A. I.; Eroshenko, S. A.


    The paper addresses the problem of alternative power supply of remote industrial clusters with renewable electric energy generation. As a result of different technologies comparison, consideration is given to wind energy application. The authors present a methodology of mean expected wind generation output calculation, based on Weibull distribution, which provides an effective express-tool for preliminary assessment of required installed generation capacity. The case study is based on real data including database of meteorological information, relief characteristics, power system topology etc. Wind generation feasibility estimation for a specific territory is followed by power flow calculations using Monte Carlo methodology. Finally, the paper provides a set of recommendations to ensure safe and reliable power supply for the final customers and, subsequently, to provide sustainable development of the regions, located far from megalopolises and industrial centres.

  1. Lean and reliable digital supply chains - case study

    Marcin Hajdul


    Full Text Available Background: Existing business model supply chains organisation results in inefficient use of transport resources, high transport costs, increasing congestions and CO2 emission. This effect has been demonstrated by research conducted by the author as well as by the European Environmental Agency. To change this situation companies are in need of affordable, realisable and trusted data-interchange solutions to take part in international trade and commerce flows. The aim of this paper is to present practical implementation of the developed by the authors concept of global freight management ecosystem and its practical implementation using T-Traco platform. Methods: Survey, desk research and real case study results were used in the paper. Reults and conclusions: Real time and global data exchange within the whole supply (including modes of transport and transport units chain is a backbone of the lean and reliable digital supply chain.

  2. 49 CFR 236.551 - Power supply voltage; requirement.


    ... 49 Transportation 4 2010-10-01 2010-10-01 false Power supply voltage; requirement. 236.551 Section... supply voltage; requirement. The voltage of power supply shall be maintained within 10 percent of rated voltage....

  3. Photovoltaic power supply for telecommunication network components in remote areas

    Steinhueser, A.; Schulz, W.; Schmidt, H.; Roth, W. [Fraunhofer Inst. for Solar Energy Systems ISE, Freiburg (Germany)


    In general, telecommunication facilities do not allow much flexibility in the choice of location; the main criterion is that the facility must work with 100% availability and reliability. Corresponding to the wide spectrum of locations, the applied power supply technologies are very diverse: grid connection, diesel generators, photovoltaics (PV), fuel cells, thermoelectric converters and wind generators. The first three types of technology have been used by the telecommunications industry for decades. The other options are at developmental stages between laboratory samples and limited series production. The traditional approach to supply power remote from the grid is by using diesel generators and storage batteries. This means high power ratings, but also high prices and a high maintenance demand. The convergence of telecommunications networks, i.e. overlap of the cabled network and radio cellular networks, with its enormous demand for installation sites, introduces new demands on power supplies: they must be reliable, maintenance-free, inexpensive, flexibly adaptable to widely divergent technologies. At two examples, a PV-hybrid system for a repeater station for cellular phones and a PV powered intelligent information system, the advantages that offer PV off-grid solutions in the system design are shown. (orig.)

  4. Power enhancement of piezoelectric transformers for power supplies

    Ekhtiari, Marzieh; Steenstrup, Anders Resen; Zhang, Zhe


    This paper studies power enhancement of piezoelectric transformers to be used in inductorless, half-bridge, piezoelecteric-based switch mode power supplies for driving a piezo actuator motor system in a high strength magnetic environment for magnetic resonance imaging and computed tomography...... applications. A new multi element-piezo transformer solution is proposed along with a dual mode piezo transformer, providing power scaling and potentially improving the internal heat-up of a high power piezo transformer system....

  5. Schedule Planning for Repairing Power Supply System

    Kuo-Wei Lin; Chein-Jen Kang


    Problem statement: Taiwan is located in the tropical ocean areas. The strong typhoon in summer often causes the collapse of electric transmission towers and results in power outages that seriously affect peoples lives and industrial production. Approach: In light of this situation, this study aims to employ project management techniques of Theory of Constraints (TOC) to develop a practical TOC model to quickly repair the towers and restore power supplied system. Results: The actual applicatio...

  6. Novel Reduced Parts Online Uninterruptible Power Supply

    Bahram Ashrafi; Mehdi Niroomand


    This paper presents design consideration and performance analysis of novel reduced parts online three-phase uninterruptible power supply (UPS) system. The proposed UPS system is based on reduced switch count dual bridge matrix converter. It employs only six power switches and results in reducing the cost of the system compared to conventional online UPS topologies, while achieving excellent performance. The performance of the proposed system is evaluated through simulation in terms of input/o...

  7. Solid state capacitor discharge pulsed power supply for railguns


    This thesis presents a solid state thyristor switched power supply capable of providing 50 kJ from a high voltage capacitor to a railgun. The efficiency with which energy is transferred from a power supply to a projectile depends strongly on power supply characteristics. This design will provide a better impedance match to the railgun than power supplies utilizing spark gap switches. This supply will cost less and take up less volume than a similar supply using spark gap switches; it wil...

  8. Dual voltage power supply with 48 volt

    Froeschl, Joachim; Proebstle, Hartmut; Sirch, Ottmar [BMW Group, Muenchen (Germany)


    Automotive electrics/electronics have just reached a period of tremendous change. High voltage systems for Hybrid, Plug-In Hybrid or Battery Electric Vehicles with high power electric motors, high energy accumulators and electric climate compressors will be introduced in order to achieve the challenging targets for CO{sub 2} emissions and energy efficiency and to anticipate the mobility of the future. Additionally, innovations and the continuous increase of functionality for comfort, safety, driver assistance and infotainment systems require more and more electrical power of the vehicle power supply at all. On the one hand side electrified vehicles will certainly achieve a significant market share, on the other hand side they will increase the pressure to conventional vehicles with combustion engines for fuel consumption and CO{sub 2} emissions. These vehicles will be enabled to keep their competitiveness by new functions and the optimization of their electric systems. A dual voltage power supply with 48 Volt and 12 Volt will be one of the key technologies to realize these requirements. The power capability of the existing 12 Volt power supply has reached its limits. Further potentials can only be admitted by the introduction of 48 Volt. For this reason the car manufacturers Audi, BMW, Daimler, Porsche and Volkswagen started very early on this item and developed a common specification of the new voltage range. Now, it is necessary to identify the probable systems at this voltage range and to start the developments. (orig.)

  9. 24 CFR 3280.803 - Power supply.


    ... must be suitable for use in wet locations; (iii) Each neutral conductor must be connected to the system... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Power supply. 3280.803 Section 3280.803 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued...

  10. Demand Response For Power System Reliability: FAQ

    Kirby, Brendan J [ORNL


    Demand response is the most underutilized power system reliability resource in North America. Technological advances now make it possible to tap this resource to both reduce costs and improve. Misconceptions concerning response capabilities tend to force loads to provide responses that they are less able to provide and often prohibit them from providing the most valuable reliability services. Fortunately this is beginning to change with some ISOs making more extensive use of load response. This report is structured as a series of short questions and answers that address load response capabilities and power system reliability needs. Its objective is to further the use of responsive load as a bulk power system reliability resource in providing the fastest and most valuable ancillary services.

  11. The Design of the Parallel Switching Power Supply System

    Bin Zhang


    Full Text Available This study introduces a parallel switching power supply system which is controlled by C8051F020 MCU. The system consists of DC/DC converter, voltage-controlled constant current source circuit, over-current protection circuit and auxiliary power supply. TPS54331 is used to constitute a highly efficient DC/DC converter, reducing the input DC voltage to supply the voltage-controlled constant current source circuit. The parallel current-sharing of the system is realized by the voltage-controlled constant current source circuit. The output current of the two parallel power supply can be adjusted by changing the control voltage. When the output current exceeds the set value, the system starts over-current protection circuit to cut off the power and delays to restore power automatically after a certain period of time. The test results show that the system is stable and reliable, easy to control and has a function of over-current protection and automatic recovery.

  12. Microgrids and Heterogeneous Power Quality and Reliability

    LaCommare, Kristina; Marnay, Chris


    This paper describes two stylized alternative visions of how the power system might evolve to meet future requirements for the high quality electricity service that modern digital economies demand, a supergrids paradigm and a dispersed paradigm. Some of the economics of the dispersed vision are explored, and perspectives are presented on both the choice of homogeneous universal power quality upstream in the electricity supply chain and on the extremely heterogeneous requirements of end-use loads. It is argued that meeting the demanding requirements of sensitive loads by local provision of high quality power may be more cost effective than increasing the quality of universal homogeneous supply upstream in the legacy grid. Finally, the potential role of microgrids in delivering heterogeneous power quality is demonstrated by reference to two ongoing microgrid tests in the U.S. and Japan.

  13. Navigating Financial and Supply Reliability Tradeoffs in Regional Drought Portfolios

    Zeff, H. B.; Herman, J. D.; Characklis, G. W.; Reed, P. M.


    Rising development costs and growing concerns over environmental impacts have led many communities to explore more diversified regional portfolio-type approaches to managing their water supplies. These strategies coordinate existing supply infrastructure with other ';assets' such as conservation measures or water transfers, reducing the capacity and costs required to meet demand by providing greater adaptability to changing hydrologic conditions. For many water utilities, however, this additional flexibility can also cause unexpected reductions in revenue (i.e. conservation) or increased costs (i.e. transfers), fluctuations that can be very difficult for a regulated entity to manage. Thus, despite the advantages, concerns over the resulting financial disruptions provide a disincentive for utilities to develop more adaptive methods, potentially limiting the role of some very effective tools. This study seeks to design portfolio strategies that employ financial instruments (e.g. contingency funds, index insurance) to reduce fluctuations in revenues and costs and therefore do not sacrifice financial stability for improved performance (e.g. lower expected costs, high reliability). This work describes the development of regional water supply portfolios in the ';Research Triangle' region of North Carolina, an area comprising four rapidly growing municipalities supplied by nine surface water reservoirs in two separate river basins. Disparities in growth rates and the respective individual storage capacities of the reservoirs provide the region with the opportunity to increase the efficiency of the regional supply infrastructure through inter-utility water transfers, even as each utility engages in its own conservation activities. The interdependence of multiple utilities navigating shared conveyance and treatment infrastructure to engage in transfers forces water managers to consider regional objectives, as the actions of any one utility can affect the others. Results

  14. NASA Ames Research Center 60 MW Power Supply Modernization

    Choy, Yuen Ching; Ilinets, Boris V.; Miller, Ted; Nagel, Kirsten (Technical Monitor)


    The NASA Ames Research Center 60 MW DC Power Supply was built in 1974 to provide controlled DC power for the Thermophysics Facility Arc Jet Laboratory. The Power Supply has gradually losing reliability due to outdated technology and component life limitation. NASA has decided to upgrade the existing rectifier modules with contemporary high-power electronics and control equipment. NASA plans to complete this project in 2001. This project includes a complete replacement of obsolete thyristor stacks in all six rectifier modules and rectifier bridge control system. High power water-cooled thyristors and freewheeling diodes will be used. The rating of each of the six modules will be 4000 A at 5500 V. The control firing angle signal will be sent from the Facility Control System to six modules via fiberoptic cable. The Power Supply control and monitoring system will include a Master PLC in the Facility building and a Slave PLC in each rectifier module. This system will also monitor each thyristor level in each stack and the auxiliary equipment.

  15. Research on the Influence of Wind-solar Hybrid Power Supply System to the Reliability of Distribution Network%风光互补发电系统对配电网可靠性的影响

    兰华; 李政阳; 王韵然


    A kind of wind-solar hybrid power supply system was introduced. The stability of distribution network will be influenced after wind and solar power paralleling in the grid because of the instantaneity and uncontrollability of wind and solar power. The minimal path method was used for calculating the stability of distribution network. Then the influence of wind-solar hybrid power supply system to distribution network was analyzed, with comparison with wind power and photovoltaic power. The conclusion is that the influence of wind-solar hybrid power supply system to distribution network is the smallest.%风能和太阳能的瞬时性和不可控性使风力发电和太阳能发电并网后会对配电网的可靠性指标造成影响。为此,介绍了一种风光互补发电系统,以最小路法对配电网的可靠性进行计算,分析风光互补发电系统对配电网的影响,并分别与单独的风力发电、光伏发电系统进行比较。得出风光互补优化后对配电网的扰动远小于单独的风力、光伏发电系统对配电网扰动的结论。

  16. Power Supplies for High Energy Particle Accelerators

    Dey, Pranab Kumar


    The on-going research and the development projects with Large Hadron Collider at CERN, Geneva, Switzerland has generated enormous enthusiasm and interest amongst all to know about the ultimate findings on `God's Particle'. This paper has made an attempt to unfold the power supply requirements and the methodology adopted to provide the stringent demand of such high energy particle accelerators during the initial stages of the search for the ultimate particles. An attempt has also been made to highlight the present status on the requirement of power supplies in some high energy accelerators with a view that, precautionary measures can be drawn during design and development from earlier experience which will be of help for the proposed third generation synchrotron to be installed in India at a huge cost.

  17. The Reliability Research of the Supply Chain Management Based on the Fuzzy Operation


    The complex and varied relationships between supply a nd demand among different enterprises calls for an effective way to evaluate and maintain reliability in supply chain management. Individually, enterprises purs ue maximum benefit strategy while cooperating with others. This behavior may res ult in the weakening of needed reliability in supply chain or, in more serious c ases, sever the supply chain. Although reliability of supply chain is the bases to ensuring long-term benefit, a systematic way of h...

  18. Novel Reduced Parts Online Uninterruptible Power Supply

    Bahram Ashrafi


    Full Text Available This paper presents design consideration and performance analysis of novel reduced parts online three-phase uninterruptible power supply (UPS system. The proposed UPS system is based on reduced switch count dual bridge matrix converter. It employs only six power switches and results in reducing the cost of the system compared to conventional online UPS topologies, while achieving excellent performance. The performance of the proposed system is evaluated through simulation in terms of input/output waveforms quality and shows the viability of topology.

  19. 46 CFR 113.10-9 - Power supply.


    ... 46 Shipping 4 2010-10-01 2010-10-01 false Power supply. 113.10-9 Section 113.10-9 Shipping COAST... SYSTEMS AND EQUIPMENT Fire and Smoke Detecting and Alarm Systems § 113.10-9 Power supply. (a) General... battery, the charger must be supplied from the final emergency power source. Upon loss of power to...


    Tirshu M.


    Full Text Available The paper deals with practical realization of efficient lighting system based on LED’s of 80W total power mounted on corridor ceiling total length of which is 120m and substitutes existing traditional lighting system consisting of 29 lighting blocks with 4 fluorescent lamps each of them and summary power 2088W. Realized lighting system is supplied from two photovoltaic panels of power 170W. Generated energy by PV cells is accumulated in two accumulators of 75Ah capacity and from battery by means of specialized convertor is applied to lighting system. Additionally, paper present data measured by digital weather station (solar radiation and UV index, which is mounted near of PV cells and comparative analyze of solar energy with real energy generated by PV cells is done. Measured parameters by digital weather station are stored by computer in on-line mode.

  1. DC power supplies power management and surge protection for power electronic systems

    Kularatna, Nihal


    Modern electronic systems, particularly portable consumer electronic systems and processor based systems, are power hungry, compact, and feature packed. This book presents the most essential summaries of the theory behind DC-DC converter topologies of both linear and switching types. The text discusses power supply characteristics and design specifications based on new developments in power management techniques and modern semiconductors entering into the portable electronics market. The author also addresses off-the-line power supplies, digital control of power supply, power supply protection

  2. Fuel-cell powered uninterruptible power supply systems: Design considerations

    Choi, Woojin; Howze, Jo. W.; Enjeti, Prasad

    A 1-kVA fuel cell powered, line-interactive uninterruptible power supply (UPS) system that employs modular (fuel cell and power converter) blocks is introduced. Two commercially available proton-exchange membrane fuel cell (25-39 V, 500 W) modules together with suitable dc-dc and dc-ac power electronic converter modules are employed. A supercapacitor module is also used to compensate for the instantaneous power fluctuations and to overcome the slow dynamics of the fuel processor (reformers). Further energy stored in the supercapacitor is also utilized to handle a momentary overload such as 200% for a short duration. Due to the absence of batteries, the system satisfies the demand for an environmentally clean source of energy. A complete design that defines the amount of hydrogen storage required for a power outage of 1 h, and the sizing of the supercapacitors for transient load demand is presented for a 1-kVA UPS.

  3. TIG welding power supply with improved efficiency

    Сергій Володимирович Гулаков


    Full Text Available In the article, the influence of the DC component of the welding current during TIG (Tungsten Inert Gas welding is discussed. Known methods of DC current cancellation are reviewed, such as capacitor bank or diode/thyristor network insertion in the secondary circuit of the welding transformer. A new method of controlling the magnitude and shape of the TIG welding current is proposed. The idea is to insert a controlled voltage source in the secondary circuit of the welding transformer. This controlled voltage source is realized using a full-bridge voltage source inverter (VSI. VSI control system design issues are discussed. VSI is controlled by a three-level hysteretic current controller, while current reference is generated using lookup table driven by PLL (Phase Locked Loop locked to the mains frequency. Simulation results are shown. The proposed topology of TIG power supply allows to provide magnitude and shape control of the welding current, with the limitation that its DC component must be zero. Thus, some capabilities of professional AC-TIG welders are obtained using substantially lower cost components: VSI built using high-current low voltage MOSFETs with control system based on 32-bit ARM microcontroller. The use of proposed TIG welding power supply will eliminate the DC component of the welding current, improve welding transformer’s power factor and improve welding technology by increasing the welding arc stability

  4. Improving Electrical Efficiency of Edm Power Supply

    Toma, Emanoil; Simion, Carmen Mihaela


    This paper briefly presents the principal types of Pulse Generators for Electrical Discharge Machining and ways to improve electrical efficiency. A resonant converter with series-parallel LCC circuit, for EDM applications, was analyzed by PSpice simulation. The performances of EDM Power Supply were improved by adding an energy recovering - voltage limiter circuit. The shape of current pulse was changed by adding a supplementary MOSFET Switch in parallel with the gap. Two or more converters can be parallelized, in this way output current can be changed. A bloc-schema was conceived for EDM experimental set up

  5. Westinghouse programs in pulsed homopolar power supplies

    Litz, D. C.; Mullan, E.


    This document details Westinghouse's ongoing study of homopolar machines since 1929 with the major effort occurring in the early 1970's to the present. The effort has enabled Westinghouse to develop expertise in the technology required for the design, fabrication and testing of such machines. This includes electrical design, electromagnetic analysis, current collection, mechanical design, advanced cooling, stress analysis, transient rotor performance, bearing analysis and seal technology. Westinghouse is using this capability to explore the use of homopolar machines as pulsed power supplies for future systems in both military and commercial applications.

  6. Ablation response testing of aerospace power supplies

    Lutz, S. A.; Chan, C. C.


    An experimental program was performed to assess the aerothermal ablation response of aerospace power supplies. Full-scale General Purpose Heat Source (GPHS) test articles, Graphite Impact Shell (GIS) test articles, and Lightweight Radioisotope Heater Unit (LWRHU) test articles were all tested without nuclear fuel in simulated reentry environments at the NASA Ames Research Center. Stagnation heating, stagnation pressure, stagnation surface temperature, stagnation surface recession profile, and weight loss measurements were obtained for diffusion-limited and sublimation ablation conditions. The recession profile and weight loss measurements showed an effect of surface features on the stagnation face. The surface features altered the local heating which in turn affected the local ablation.

  7. Reliability of emergency ac power systems at nuclear power plants

    Battle, R E; Campbell, D J


    Reliability of emergency onsite ac power systems at nuclear power plants has been questioned within the Nuclear Regulatory Commission (NRC) because of the number of diesel generator failures reported by nuclear plant licensees and the reactor core damage that could result from diesel failure during an emergency. This report contains the results of a reliability analysis of the onsite ac power system, and it uses the results of a separate analysis of offsite power systems to calculate the expected frequency of station blackout. Included is a design and operating experience review. Eighteen plants representative of typical onsite ac power systems and ten generic designs were selected to be modeled by fault trees. Operating experience data were collected from the NRC files and from nuclear plant licensee responses to a questionnaire sent out for this project.

  8. Preferred external power supplies; Fuentes electricas preferentes exteriores

    Martinez Anton, L.


    In June 2008 ANAV and ENDESA DISTRIBUCION (EDE) undertook a joint study of Asco NPP Preferred External Power Supplies (PEPSs) to check the number of lines or power supplies to the 110 kV substation at Asco that met the criteria defined in the power supply regulations applicable to Asco NPP and primarily to confirm compliance with IEEE 765-2006 standard. (Author).

  9. Electric power supply and demand for the contiguous United States, 1980-1989



    A limited review is presented of the outlook for the electric power supply and demand during the period 1980 to 1989. Only the adequacy and reliability aspects of bulk electric power supply in the contiguous US are considered. The economic, financial and environmental aspects of electric power system planning and the distribution of electricity (below the transmission level) are topics of prime importance, but they are outside the scope of this report.

  10. Schedule Planning for Repairing Power Supply System

    Kuo-Wei Lin


    Full Text Available Problem statement: Taiwan is located in the tropical ocean areas. The strong typhoon in summer often causes the collapse of electric transmission towers and results in power outages that seriously affect peoples lives and industrial production. Approach: In light of this situation, this study aims to employ project management techniques of Theory of Constraints (TOC to develop a practical TOC model to quickly repair the towers and restore power supplied system. Results: The actual application had verified that the research model could not only shorten the duration of work but also save the manpower and material expenses. Conclusion: It once again proved the excellent results of reparation operations by applying TOC to project management.

  11. Battery requirements for uninterruptible power-supply applications

    Brownlie, G. D.

    There is an expanding market for small-to-medium capacity secondary batteries for use in uninterruptible power supplies (UPSs). UPSs are commonly used to provide protected power to computer installations, point-of sale terminals, and essential telecommunications equipment. The capacity of currently available UPSs is, typically, from 500 VA to several hundred kVa, with power-backup from ten minutes to one hour at full load. All UPSs incorporate secondary batteries; usually sealed lead/acid cells. Battery requirements include: high reliability; extended operating life; tolerance to extended float charging; and good, deep-discharge characteristics at high discharge rates. Recent research and development experiences in the design of a range of UPSs is described and the need for batteries optimised for UPS applications is highlighted.

  12. High performance magnet power supply optimization

    Jackson, L.T.


    The power supply system for the joint LBL--SLAC proposed accelerator PEP provides the opportunity to take a fresh look at the current techniques employed for controlling large amounts of dc power and the possibility of using a new one. A basic requirement of +- 100 ppM regulation is placed on the guide field of the bending magnets and quadrupoles placed around the 2200 meter circumference of the accelerator. The optimization questions to be answered by this paper are threefold: Can a firing circuit be designed to reduce the combined effects of the harmonics and line voltage combined effects of the harmonics and line voltage unbalance to less than 100 ppM in the magnet field. Given the ambiguity of the previous statement, is the addition of a transistor bank to a nominal SCR controlled system the way to go or should one opt for an SCR chopper system running at 1 KHz where multiple supplies are fed from one large dc bus and the cost--performance evaluation of the three possible systems.

  13. Thermal Impact Analysis of Circulating Current in High Power Modular Online Uninterruptible Power Supplies Application

    Zhang, Chi; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez


    In modular uninterruptible power supplies (UPSs), several DC/AC modules are required to work in parallel. This structure allows the system to be more reliable and flexible. These DC/AC modules share the same DC bus and AC critical bus. Module differences, such as filter inductor, filter capacitor......, control parameters, and so on, will make it possible for the potential zero sequence current to flow among the modules. This undesired type of circulating current will bring extra losses to the power semiconductor devices in the system, which should be paid special attention in high power application...

  14. High precision power supplies for the National Synchrotron Light Source

    Olsen, R.; Langenbach, H.


    Since beam stability depends to a considerable degree on the stability of the magnet power supplies, and it is desired to push for 3 GeV operation, it was required that new power supplies be obtained for the quadrupoles and sextupoles. These power supplies were to have the lowest ripple that could be reasonably achieved, and were to have a current regulation of better than 10 PPM. In addition, since they operate over a 5 : 1 voltage range, it was considered desirable to ensure that they operated with a good power factor over the operating range. The dipole power supply was modified to use the techniques employed in the smaller supplies.

  15. Reliable and cost effective micro hydro power



    A 14 kW hydroelectric power plant in British Columbia that generates enough power to run a small farm was described. It was developed as an alternative to bringing in power from BC Hydro, which would have cost about the same initially, but would also have entailed about $300 per month of utility bills. The system operates at a fraction of its capacity at practically no operating cost and the capital outlay will have been recovered in six to seven years. The system uses a Lima generator directly coupled to a pelton turbine. Some 1,400 feet of five inch PCV pipe running down a hillside provides 136 psi of static pressure. The pressurized water in the pipeline squirts through a nozzle and the jet of water strikes the buckets of the pelton turbine. The energy in the water is transferred to the turbine and provides the shaft power to drive the generator. Two electrically heated dwellings, a workshop and a barn containing 300 pigs are supplied by the power plant.

  16. Neutron generator power supply modeling in EMMA

    Robinson, A.C.; Farnsworth, A.V.; Montgomery, S.T.; Peery, J.S; Merewether, K.O.


    Sandia National Laboratories has prime responsibility for neutron generator design and manufacturing, and is committed to developing predictive tools for modeling neutron generator performance. An important aspect of understanding component performance is explosively driven ferroelectric power supply modeling. EMMA (ElectroMechanical Modeling in ALEGRA) is a three dimensional compile time version of Sandia`s ALEGRA code. The code is built on top of the general ALEGRA framework for parallel shock-physics computations but also includes additional capability for modeling the electric potential field in dielectrics. The overall package includes shock propagation due to explosive detonation, depoling of ferroelectric ceramics, electric field calculation and coupling with a general lumped element circuit equation system. The AZTEC parallel iterative solver is used to solve for the electric potential. The DASPK differential algebraic equation package is used to solve the circuit equation system. Sample calculations are described.

  17. 46 CFR 113.43-5 - Power supply.


    ... 46 Shipping 4 2010-10-01 2010-10-01 false Power supply. 113.43-5 Section 113.43-5 Shipping COAST... SYSTEMS AND EQUIPMENT Steering Failure Alarm Systems § 113.43-5 Power supply. Each steering failure alarm system must be supplied by a circuit that: (a) Is independent of other steering gear system and...

  18. Power supply system for KSTAR neutral beam injector

    Cho, W., E-mail:; Bae, Y.S.; Han, W.S.; Jeong, J.H.; Kim, J.S.; Park, H.T.; Yang, H.L.; Oh, Y.K.; Kwak, J.G.


    Highlights: • The power supply system in KSTAR NBI consists of DC power supplies for ion source. • For operation NBI, DC High Voltage based on the low voltage transformer with chopper. • The surge absorber near the ion source limit the energy deposited to accelerator grid. - Abstract: The power supply system in KSTAR neutral beam injector consists of low voltage and high current DC power supplies for plasma generator of ion source and high voltage and high current DC power supply for accelerator grid system. The arc discharge is initiated by an arc power supply supplying the arc voltage between the chamber wall and 12 filaments which are heated by individual filament power supply. The negative output of arc power supply is common to each positive output of 12 filament power supplies. To interrupt the arc discharging for the fault condition of the arc current unbalance, DCCT current monitor is placed at the positive output cable of the filament power supply. The plasma grid (G1) power supply has the maximum capability of 120 kV/70 A which consists of low voltage regulator with IGBT-switched chopper array system for the voltage control in unit of 600 V and the high voltage rectified transformers to supply DC voltage of 20 kV, 30 kV, and 50 kV. The output voltage of the G1 power supply is also connected to the input of the voltage divider system which supplies the gradient voltage to the gradient grid (G2) in the range of 80–90% of G1 voltage by changing tap of winding resistors in unit of 1%. The charged G1 voltage is turned on and off by the high voltage switch (HVS) system consisting of MOSFET fast semiconductor switches which can immediately be opened less than 1 μs when the ion source grid breakdown occurs. The decelerating grid (G3) power supply is inverter system using capacitor-charge power supply to supply maximum −5 kV/5 A. The important component in power supply system is the surge absorber near the ion source to limit the arc energy deposited to

  19. Study on Modeling and Simulation of Reliability Diagnosis of Supply Chain Based on Common Cause Failure

    Guohua Chen


    Full Text Available To diagnose key factors which cause the failure of supply chain, on the base of taking 3-tier supply chain centering on manufacturer as the object, the diagnostic model of reliability of supply chain with common cause failure was established. Then considering unreliability and key importance as quantitative index, the diagnostic algorism of key factors of reliability of supply chain with common cause failure was studied by the method of Monte Carlo Simulation. The algorism can be used to evaluate the reliability of f supply chain and determine key factors which cause the failure of supply chain, which supplies a new method for diagnosing reliability of supply chain based on common cause failure. Finally, an example was presented to prove the feasibility and validity of the model and method.

  20. The Environment Friendly Power Source for Power Supply of Mobile Communication Base Stations

    Rudenko, N. V.; Ershov, V. V.; Evstafiev, V. V.


    The article describes the technical proposals to improve environmental and resource characteristics of the autonomous power supply systems of mobile communication base stations based on renewable energy sources, while ensuring the required reliability and security of power supply. These include: the replacement of diesel-generator with clean energy source - an electrochemical generator based on hydrogen fuel cells; the use of wind turbines with a vertical axis; use of specialized batteries. Based on the analysis of the know technical solutions, the structural circuit diagram of the hybrid solar-wind-hydrogen power plant and the basic principles of the algorithm of its work were proposed. The implementation of these proposals will improve the environmental and resource characteristics.

  1. Power supply devices and systems of relay protection

    Gurevich, Vladimir


    Power Supply Devices and Systems of Relay Protection brings relay protection and electrical power engineers a single, concentrated source of information on auxiliary power supply systems and devices. The book also tackles specific problems and solutions of relay protection power supply systems and devices, which are often not dealt with in the literature. The author, an experienced engineer with more than 100 patents, draws on his own experience to offer practical, tested advice to readers. A Guide to Relay Protection Power Supply for Engineers and Technicians The first chapter reviews the ele

  2. Electric Power Supply Chain Management Addressing Climate Change

    Wang, Xiao-Hui; Cong, Ronggang


    change. The study compared the difference between electric power supply chain management and traditional supply chain management. Furthermore, some possible research topics are addressed. The aim of this paper was to promote the application of supply chain management in the China electricity sector......Supply chain management played a critical role in the electric power industrial chain optimization. The purpose of this paper was to review a sample of the literature relating to supply chain management and its possible applications in electricity power system, especially in the context of climate...... optimizations and brought a change in the related government policy options....

  3. 46 CFR 113.25-6 - Power supply.


    ... 46 Shipping 4 2010-10-01 2010-10-01 false Power supply. 113.25-6 Section 113.25-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING COMMUNICATION AND ALARM SYSTEMS AND EQUIPMENT General Emergency Alarm Systems § 113.25-6 Power supply. The emergency power...

  4. One of the power supplies used for electrostatic separators


    Internal part of a power supply SAME (± 600 kV, 4 mA). These power supplies were used to power the electrodes (positive and negative), 1 to 9 m length, within a conditioned tank with Ne (30%)/He (70%) at less than a thousandth of mbar. Here, Michel Zahnd, Jean Chaminaud

  5. Improvement of Main Magnetic Field Power Supply of SFC

    ZhangXianlai; YanHuaihai; XinJunye; ZhangShu


    The main magnetic field power supply is used for establishing main magnetic field of SFC, therefore excellent current stability and low ripple are required. Its DC output current range is 0~1300 A and max output voltage is 230 V. The power supply has been put into operation since Sep. in 2000, and was replaced in 033 room from 166 room of No.2 Building. We have improved the performance of power supply in this period.

  6. Electrical part Temelin NPP - important electrical appliance power supply

    Trnka, Radek


    Radek Trnka Department of Physics, Faculty of Education, University of South Bohemia Electrical part of Temelin Nuclear Power Station - Power supply of important electrical appliances The subject of this bachelor's work is an elaboration of problems of secured electric power supply for all important appliances in Temelin Nuclear Power Station (JE Temelin). There is an essential electrical conception of the nuclear power station described there, as well as possibilities of failure state emerge...

  7. Application of SAW method for multiple-criteria comparative analysis of the reliability of heat supply organizations

    Akhmetova, I. G.; Chichirova, N. D.


    Heat supply is the most energy-consuming sector of the economy. Approximately 30% of all used primary fuel-and-energy resources is spent on municipal heat-supply needs. One of the key indicators of activity of heat-supply organizations is the reliability of an energy facility. The reliability index of a heat supply organization is of interest to potential investors for assessing risks when investing in projects. The reliability indices established by the federal legislation are actually reduced to a single numerical factor, which depends on the number of heat-supply outages in connection with disturbances in operation of heat networks and the volume of their resource recovery in the calculation year. This factor is rather subjective and may change in a wide range during several years. A technique is proposed for evaluating the reliability of heat-supply organizations with the use of the simple additive weighting (SAW) method. The technique for integrated-index determination satisfies the following conditions: the reliability level of the evaluated heat-supply system is represented maximum fully and objectively; the information used for the reliability-index evaluation is easily available (is located on the Internet in accordance with demands of data-disclosure standards). For reliability estimation of heat-supply organizations, the following indicators were selected: the wear of equipment of thermal energy sources, the wear of heat networks, the number of outages of supply of thermal energy (heat carrier due to technological disturbances on heat networks per 1 km of heat networks), the number of outages of supply of thermal energy (heat carrier due to technologic disturbances on thermal energy sources per 1 Gcal/h of installed power), the share of expenditures in the cost of thermal energy aimed at recovery of the resource (renewal of fixed assets), coefficient of renewal of fixed assets, and a coefficient of fixed asset retirement. A versatile program is developed

  8. Temperature Stabilized Characterization of High Voltage Power Supplies

    Krarup, Ole


    High precision measurements of the masses of nuclear ions in the ISOLTRAP experiment relies on an MR-ToF. A major source of noise and drift is the instability of the high voltage power supplies employed. Electrical noise and temperature changes can broaden peaks in time-of-flight spectra and shift the position of peaks between runs. In this report we investigate how the noise and drift of high-voltage power supplies can be characterized. Results indicate that analog power supplies generally have better relative stability than digitally controlled ones, and that the high temperature coefficients of all power supplies merit efforts to stabilize them.

  9. Magnetically switched power supply system for lasers

    Pacala, Thomas J. (Inventor)


    A laser power supply system is described in which separate pulses are utilized to avalanche ionize the gas within the laser and then produce a sustained discharge to cause the gas to emit light energy. A pulsed voltage source is used to charge a storage device such as a distributed capacitance. A transmission line or other suitable electrical conductor connects the storage device to the laser. A saturable inductor switch is coupled in the transmission line for containing the energy within the storage device until the voltage level across the storage device reaches a predetermined level, which level is less than that required to avalanche ionize the gas. An avalanche ionization pulse generating circuit is coupled to the laser for generating a high voltage pulse of sufficient amplitude to avalanche ionize the laser gas. Once the laser gas is avalanche ionized, the energy within the storage device is discharged through the saturable inductor switch into the laser to provide the sustained discharge. The avalanche ionization generating circuit may include a separate voltage source which is connected across the laser or may be in the form of a voltage multiplier circuit connected between the storage device and the laser.

  10. Employment within the power supply industry and the power supply related activities 2010; Sysselsatte i kraftnaeringen og kraftrelatert virksomhet 2010

    Thoen, Haavard


    The report's main objective is to investigate employment within the power supply industry and the power supply related activities. The report will describe the composition of employees in regard to sex, age and education. The power supply industry is defined in Statistics Norway's Standard Industrial Classification, as 'Production and distribution of electricity'. The group of companies related to power supply related activities employ similar persons in regard to education and occupation, typical to companies in the power supply industry. In the report, these two groups make up the power supply sector. In 2010 there were 18215 employees in the power supply sector. This constitutes an increase of nearly 12 per cent since 2004 and 1,7 per cent since 2008. The sex distribution of about 80 per cent men and 20 per cent women has been fairly stable since 2004. Compared to the private sector in general the power supply sector has a low share of women among its employees. In 2009 the level of education in the power supply sector was higher than for the private sector in general. Since 2004, the share of persons with higher education has increased from 27 to 33 per cent. Employees in the power supply sector are on an average older than the employees in the private sector. The employees have matured since 2004, but in the last few years, there have also been signs of fresh recruitment. The power supply industry had a net influx of 347 new employees, or 2 percent, in the period between 2009 and 2010. There were 1522 new employees and 1175 employees lost in the sector due to attrition, which gives a turnover rate of 20 percent. If we look at the supply of new employees who were also employed in 2009, 19 percent of female employees worked in temporary staff recruitment agencies. This indicates that temporary work was an entry gate to the power supply industry for many women. Among men, the building- and construction sector was the most common background for

  11. Combating the Reliability Challenge of GPU Register File at Low Supply Voltage

    Tan, Jingweijia; Song, Shuaiwen; Yan, Kaige; Fu, Xin; Marquez, Andres; Kerbyson, Darren J.


    Supply voltage reduction is an effective approach to significantly reduce GPU energy consumption. As the largest on-chip storage structure, the GPU register file becomes the reliability hotspot that prevents further supply voltage reduction below the safe limit (Vmin) due to process variation effects. This work addresses the reliability challenge of the GPU register file at low supply voltages, which is an essential first step for aggressive supply voltage reduction of the entire GPU chip. We propose GR-Guard, an architectural solution that leverages long register dead time to enable reliable operations from unreliable register file at low voltages.

  12. The Power of Supply Chain Finance

    Michiel Steeman


    Supply chain finance krijgt steeds meer aandacht bij bedrijven als een middel om hun supply chain strategie te ondersteunen. Het gaat hierbij niet alleen om het reduceren van kosten maar ook om het mitigeren van de risico’s in de keten. Wij verwachten dan ook dat vooral bij grote bedrijven de

  13. Quality assurance for CMS Tracker LV and HV Power Supplies

    Costa, Marco; Sertoli, M; Trapani, P; Periale, L; Isabella, L; Landi, C; Lucchesi, A


    This work describes the quality assurance measurements that have been carried out on about 2000 Power Supply Units produced in CAEN technology for the CMS Silicon Tracker Detector. The automate procedure and the characteristics of the dedicated Test Fixture developed for this activity are described in details. Magnetic field tolerance and radiation hardness of Tracker power supply units is also discussed at length.

  14. Requirements Specication for Ampliers and Power Supplies in Active Loudspeakers

    Schneider, Henrik; Jensen, Lasse Crone; Petersen, Lars Press


    This work aims to provide designers with a method to develop a requirements specication for power supplies and ampliers in active loudspeakers. The motivation is to avoid over-sizing and unnecessary cost. A realistic estimation of the power supplied during playback of audio in a given loudspeaker...

  15. Intense neutron source: high-voltage power supply specifications

    Riedel, A.A.


    This report explains the need for and sets forth the electrical, mechanical and safety specifications for a high-voltage power supply to be used with the intense neutron source. It contains sufficient information for a supplier to bid on such a power supply.

  16. Control Electronics for Solar/Flywheel Power Supply

    Nola, F. J.


    Control circuit automatically directs flow of electrical energy to and from motor with flywheel that constitutes storage element of solar-power system. When insolation is sufficient for charging, power is supplied by solar-cell array to load and motor. During periods of darkness, motor made to act as generator, drawing kinetic energy from flywheel and supplying it to load.

  17. Modular high voltage power supply for chemical analysis

    Stamps, James F.; Yee, Daniel D.


    A high voltage power supply for use in a system such as a microfluidics system, uses a DC-DC converter in parallel with a voltage-controlled resistor. A feedback circuit provides a control signal for the DC-DC converter and voltage-controlled resistor so as to regulate the output voltage of the high voltage power supply, as well as, to sink or source current from the high voltage supply.

  18. Measurement of H!gh Power Current-Stabilized Power Supply with High Stability

    YanHuaihai; FengXiuming; BaiZhen; ZhouZhongzu


    The DC power supply system of HIRFL has been upgraded since 1999, these new power supplies are used mainly as high frequency ZVS soft-switching converters or thyristor phase-controlled rectifiers. Each power supply is strictly tested before being put into operation, especially for long-term current stability, current ripple, efficiency, repeatability, EMI and so on. The tested results indicated that performances of power supplies satisfy requirement of HIRFL.

  19. Solid state modulator for klystron power supply XFEL TDS INJ

    Zavadtsev, A. A.; Zavadtsev, D. A.; Zybin, D. A.; Churanov, D. V.; Shemarykin, P. V.


    The transverse deflecting system XFEL TDS INJ for European X-ray Free Electron Laser includes power supply for the CPI VKS-8262HS klystron. It has been designed for pulse high-voltage, cathode heating, solenoid and klystron ion pump. The klystron power supply includes solid state modulator, pulse transformer, controlled power supply for cathode heating and commercial power supplies for solenoid and ion pump. Main parameters of the modulator are 110 kV of peak voltage, 72 A peak current, and pulse length up to 6 μs. The klystron power supply has been developed, designed, manufactured, tuned, tested and installed in the XFEL building. All designed parameters are satisfied.

  20. Startup experience with the MFTF-B ECRH 100 kV dc power supply

    Bishop, S.R.; Goodman, R.A.; Wilson, J.H.


    One of the 24 Accel dc Power Supplies (ADCPS) originally intended for the Mirror Fusion Test Facility (MFTF-B) Neutral Beam Power Supply (NBPS) System has been converted to provide negative polarity output at 90 kV with a load current of 64 A dc. The load duty cycle is a pulse of 30-seconds duration with a pulse repetition period of five minutes. A new control system has been built which will serve as a prototype for the MFTF-B ADCPS controls, and a test setup was built which will be used to test the ADCPS. The Electron Cyclotron Resonance Heating (ECRH) dc Power Supply (DCPS) has been tested under both no-load and dummy-load conditions, under remote control, without notable problems. Test results indicate that the power supply should be reliable and safe to operate, and will meet the load duty requirements.

  1. Employment within the power supply industry and the power supply related activities; Sysselsatte i kraftnaeringen og kraftrelatert virksomhet 2011

    Thoen, Haavard


    The report's main objective is to investigate employment within the power supply industry and the power supply related activities. The report will describe the composition of employees in regard to sex, age and education. The power supply industry is defined in Statistics Norway's Standard Industrial Classification, as 'Production and distribution of electricity'. The group of companies related to power supply related activities employ similar persons in regard to education and occupation, typical to companies in the power supply industry. These two groups make up the power supply sector in this report. In 2011 there were 18 450 employees in the power supply sector. This constitutes an increase of nearly 13.5 per cent since 2004 and 1.1 per cent since 2010. The sex distribution of about 80 per cent men and 20 per cent women has been fairly stable since 2004. The power supply sector has a low share of women among its employees compared to the private sector in general. In 2011 the level of education in the power supply sector was higher than for the private sector in general. Since 2004, the share of persons with higher education has increased from 27 to 33 per cent. Employees in the power supply sector are on average older than employees in the private sector. The employees have matured since 2004, but in the last few years, there have also been signs of fresh recruitment. The power supply industry had a net influx of 380 new employees, in the period between 2009 and 2011. There were 1678 new employees and 1298 employees lost in the sector due to attrition. If we look at the supply of new employees who were also employed in 2010, 14.2 percent of female employees worked in temporary staff recruitment agencies. Temporary work seems to be an important entry gate to the power supply industry for women. Among men, the building- and construction sector was the most common background for new employees in the power supply industry. Among people who quit

  2. Cooperative Communications. Link Reliability and Power Efficiency

    Ahsin, Tafzeel ur Rehman


    Demand for high data rates is increasing rapidly for the future wireless generations, due to the requirement of ubiquitous coverage for wireless broadband services. More base stations are needed to deliver these services, in order to cope with the increased capacity demand and inherent unreliable nature of wireless medium. However, this would directly correspond to high infrastructure cost and energy consumption in cellular networks. Nowadays, high power consumption in the network is becoming a matter of concern for the operators,both from environmental and economic point of view. Cooperative communications, which is regarded as a virtual multi-input-multi-output (MIMO) channel, can be very efficient in combating fading multi-path channels and improve coverage with low complexity and cost. With its distributed structure, cooperative communications can also contribute to the energy efficiency of wireless systems and green radio communications of the future. Using network coding at the top of cooperative communication, utilizes the network resources more efficiently. Here we look at the case of large scale use of low cost relays as a way of making the links reliable, that directly corresponds to reduction in transmission power at the nodes. A lot of research work has focused on highlighting the gains achieved by using network coding in cooperative transmissions. However, there are certain areas that are not fully explored yet. For instance, the kind of detection scheme used at the receiver and its impact on the link performance has not been addressed.The thesis looks at the performance comparison of different detection schemes and also proposes how to group users at the relay to ensure mutual benefit for the cooperating users.Using constellation selection at the nodes, the augmented space formed at the receiver is exploited for making the links more reliable. The network and the channel coding schemes are represented as a single product code, that allows us to

  3. Dynamic Analysis & Characterization of Conventional Hydraulic Power Supply Units

    Schmidt, Lasse; Liedhegener, Michael; Bech, Michael Møller


    Hydraulic power units operated as constant supply pres-sure systems remain to be widely used in the industry, to supply valve controlled hydraulic drives etc., where the hydraulic power units are constituted by variable pumps with mechanical outlet pressure control, driven by induction motors...... and drives will reduce the flow-to-pressure gain of the supply system, and hence increase the time constant of the sup-ply pressure dynamics. A consequence of this may be large vari-ations in the supply pressure, hence large variations in the pump shaft torque, and thereby the induction motor load torque......, with possible excitation of the induction motor dynamics as a result. In such cases, the coupled dynamics of the pressure controlled pump and induction motor may influence the supply pressure sig-nificantly, possibly affecting the dynamics of the supplied drives, especially in cases where pilot operated valves...

  4. Reliability and M. T. T. F. analysis of a power plant consisting of three generators by Boolean Function technique

    Gupta, P.P.; Sharma, R.K.


    The reliability behaviour of a non-repairable parallel redundant complex system which is nothing but a power plant is investigated. The object of the system is to supply power generated by three generators from a power house to a very critical consumer, connected by cables and switches etc. The reliability of the power supply to the critical consumer has been obtained by using the Boolean Function technique. Moreover, an important parameter of reliability, viz. M.T.T.F. (mean time to failure), has also been computed for exponential failure rates of components. A numerical example with graphs has also been appended in the end to highlight the important results.

  5. Reliability of electrical power systems for coal mines

    Razgil' deev, G.I.; Kovalev, A.P.; Serkyuk, L.I.


    This is a method for evaluating the reliability of comprehensive mining power systems. The systems reliability is influenced by the selectivity of maximum protection, ground-short protection, the subdivision of the circuitry, the character of the systems failures, etc.

  6. 提高固定污染源烟气排放连续监测系统供电电源可靠性的设计与研究%Continuous Monitoring System of Flue Gas Emission From Fixed Pollution Source Design and Research on Reliability of Power Supply



    This paper research the stationary pol ution source smoke emission CEMS power supply reliability as a starting point,using existing plant UPS power supply resources,and presents a research scheme is designed,and successful y ap-plied in Tianjiaan power plant #5 unit.%CEMS(Continuous Emission Monitoring System)又称为“连续监测系统”,目前国内各大电厂都采用热工电源柜提供的带备自投的双路电源对固定污染源烟气排放CEMS进行供电。以提高固定污染源烟气排放CEMS供电电源可靠性为出发点,利用电厂现有的UPS电源资源,提出一套设计研究方案,并成功应用于田家庵电厂#5机组。

  7. Planning Mechanisms for Regional Electric Power Supply System Development

    Evgeniy Anatolyevich Malyshev


    Full Text Available Key problems of the regional electric power supply systems are examined. These problems result from a lack of regulated interaction mechanisms for uniting the different entities’ resources aimed at the realization of investment activities. One of the main problems of the power supply industry is physical and moral aging of both generating and networking equipment. In the article, the necessity of management system formation to control the development of power sector has been proved. The deficiencies of the modern investment procedure in power companies are described. The absence of continuity between the regional and local strategic planning documents and investment planning of a power company has been found out. The possibility to develop a new mechanism for attracting investment has been proposed. The regulation of joint activities to implement the development program for the regional power supply industry has been proposed. The management system to develop the Russian power industry has been proposed. The comparative analysis of generating capacity development mechanisms has been carried out, such as capacity supply agreement (CSA, investment support mechanism (ISM, and long-term power market (LPM. The interaction procedure of the planning of the power supply infrastructure development has been described. The mechanism connecting the state sectoral and regional planning and corporate planning of power supply infrastructure development has been proposed. The regional aspects of industrial policy and its legislative support have been considered. To successfully implement the public-private-partnership (PPP projects, it is necessary to create the effective PPP model within the federal and regional legislation framework; to develop the financial model providing the recoverability of investments; to provide a mutually beneficial cooperation between executive bodies and private investors. The possibility to apply the PPP mechanism for regional

  8. Power supply distribution system for calorimeters at the LHC beyond the nominal luminosity

    Tenti, P; Spiazzi, G; Buso, S [Dipartimento di Ingegneria dell' Informazione, Universita degli Studi di Padova, via Gradenigo 6/b, Padova (Italy); Riva, M; Maranesi, P; Belloni, F [Departimento di Fisica, Universita degli Studi di Milano, via Celoria 16, Milano (Italy); Cova, P; Menozzi, R; Delmonte, N; Bernardoni, M [Dipartimento di Ingegneria dell' Informazione, Universita degli Studi di Parma, v.le G.P. Usberti, 181/A, Parma (Italy); Iannuzzo, F; Busatto, G; Porzio, A; Velardi, F [Dip. di Automazione, Elettromagnetismo, Ingegneria dell' Informazione e Matematica Industriale, Universita degli Studi di Cassino, via G. Di Biasio 43, Cassino (France) (Italy); Lanza, A [INFN - Sezione di Pavia, via A. Bassi 6, Pavia (Italy); Citterio, M; Meroni, C, E-mail: [INFN - Sezione di Milano, via Celoria 16, Milano (Italy)


    This paper investigates the use of switching converters for the power supply distribution to calorimeters in the ATLAS experiment when the Large Hadron Collider (LHC) will be upgraded beyond the nominal luminosity. Due to the highly hostile environment the converters must operate in, all the main aspects are considered in the investigation, from the selection of the switching converter topologies to the thermal analysis of components and PCBs, with attention to reliability issues of power devices subject to ionizing radiations. The analysis focuses on the particular, but crucial, case of the power supplies for calorimeters, though several outcomes of the research can profitably be applied to other detectors like muon chambers.

  9. Reliability Oriented Circuit Design For Power Electronics Applications

    Sintamarean, Nicolae Cristian


    Highly reliable components are required in order to minimize the downtime during the lifetime of the converter and implicitly the maintenance costs. Therefore, the design of high reliable converters under constrained reliability and cost is a great challenge to be overcome in the future. The temperature variation of the semiconductor devices plays a key role in the robustness design and reliability of power electronics converters. This factor has a major impact on the power converters used in...

  10. Analysis of power supply circuits for electroluminescent panels

    Drumea, Andrei; Dobre, Robert Alexandru


    The electroluminescent panel is a light emitting device that requires for normal operations alternative voltages with peak to peak amplitudes in 100V… 300V range and frequencies in 100Hz … 2 kHz range. Its advantages, when compared with standard light sources like incandescent lamps, gas-discharge lamps or light emitting diodes (LEDs), are lower power consumption, flexible substrate and uniform light without observable luminous points. One disadvantage of electroluminescent panels is the complex power supply required to drive them, but the continuous improvement in passive and active integrated devices for switched mode power supplies will eventually solve this issue. The present paper studies different topologies for these power supplies and the effect of the electric parameters like the amplitude, frequency, waveform of the supplying voltage on the light emission and on power consumption for electroluminescent panels with different size and colors.

  11. Thermal control of power supplies with electronic packaging techniques


    The analysis, design, and development work to reduce the weight and size of a standard modular power supply with a 350 watt output was summarized. By integrating low cost commercial heat pipes in the redesign of this power supply, weight was reduced by 30% from that of the previous design. The temperature was also appreciably reduced, increasing the environmental capability of the unit. A demonstration unit with a 100 watt output and a 15 volt regulator module, plus simulated output modules, was built and tested to evaluate the thermal performance of the redesigned power supply.

  12. The Economics of Groundwater Replenishment for Reliable Urban Water Supply

    Lei Gao; Connor, Jeffery D.; Peter Dillon


    This paper explores the potential economic benefits of water banking in aquifers to meet drought and emergency supplies for cities where the population is growing and changing climate has reduced the availability of water. A simplified case study based on the city of Perth, Australia was used to estimate the savings that could be achieved by water banking. Scenarios for investment in seawater desalination plants and groundwater replenishment were considered over a 20 year period of growing de...

  13. Pivotal suppliers and market power in experimental supply function competition

    Brandts, J.; Reynolds, S.; Schram, A.


    In the process of regulatory reform in the electric power industry, the mitigation of market power is one of the basic problems regulators have to deal with. We use experimental data to study the sources of market power with supply function competition, akin to the competition in wholesale electrici

  14. A Robust Modular IGBT Power Supply for Fusion Science Applications

    Ziemba, Timothy; Miller, Ken; Prager, James


    A present challenge facing the fusion energy community and particularly the ICC community in its support of the main line tokamak program is the ability to generate increased power levels for pulsed magnets, arc plasma sources, radio frequency heating, and current drive schemes, at reasonable cost. Continuous wave (CW) tube based power supplies are typically large and expensive, making them prohibitive for smaller experimental facilities or not cost effective when only pulsed input power is required. Continued research and development of next generation solid state power supplies could allow for multiple applications with a single well developed, low cost module that could be configured in many ways. Eagle Harbor Technologies has developed, built, and tested a modular solid state power supply based on Insulate Gate Bi-polar Transistor (IGBT) technologies. The power supply utilized a modular, low cost, high power IGBT based system that can be assembled in multiple ways to address a wide range of applications. Testing results demonstrating the prototype abilities in both parallel and series configurations and for both high current and/or high voltage operation will be presented. The prototype cost was shown to be significantly lower than older generation power supplies for similar applications. Future work includes upgrading the prototype for increased power levels (> 10 MW).

  15. Operation Optimization Based on the Power Supply and Storage Capacity of an Active Distribution Network

    Wenpeng Yu


    Full Text Available Due to the interconnection and active management of Distributed Generation (DG and Energy Storage Systems (ESSs, the traditional electrical distribution network has become an Active Distribution Network (ADN, posing challenges to the operation optimization of the network. The power supply and storage capacity indexes of a Local Autonomy Control Region (LACR, which consists of DGs, ESSs and the network, are proposed in this paper to quantify the power regulating range of a LACR. DG/ESS and the network are considered as a whole in the model of the indexes, considering both network constraints and power constraints of the DG/ESS. The index quantifies the maximum LACR power supplied to or received from ADN lines. Similarly, power supply and storage capacity indexes of the ADN line are also proposed to quantify the maximum power exchanged between ADN lines. Then a practical algorithm to calculate the indexes is presented, and an operation optimization model is proposed based on the indexes to maximum the economic benefit of DG/ESS. In the optimization model, the power supply reliability of the ADN line is also considered. Finally, the indexes of power supply and storage capacity and the optimization are demonstrated in a case study.

  16. Safety of power transformers, power supplies, reactors and similar products - Part 1: General requirements and tests

    International Electrotechnical Commission. Geneva


    This International Standard deals with safety aspects of power transformers, power supplies, reactors and similar products such as electrical, thermal and mechanical safety. This standard covers the following types of dry-type transformers, power supplies, including switch mode power supplies, and reactors, the windings of which may be encapsulated or non-encapsulated. It has the status of a group safety publication in accordance with IEC Guide 104.

  17. Solid State Capacitor Discharge Pulsed Power Supply Design for Railguns


    CAPACITOR DISCHARGE PULSED POWER SUPPLY DESIGN FOR RAILGUNS by Jesse H. Black March 2007 Thesis Advisor: Alexander L. Julian Co-Advisor...switched power supply capable of providing 50 kJ from a high voltage capacitor to a railgun . The efficiency with which energy is transferred from a...also produce a smaller electromagnetic pulse. Voltage limitations on the thyristors require two in series acting as a single switch. Railgun

  18. Supply reliability and dynamic safety analysis of an alternative energy supply chain

    Herbert-Hansen, Zaza Nadja Lee; Markert, Frank; Jacobsen, Peter


    This paper focuses on the integration of risk and supply chain modelling by means of analysing a case concerning a Hydrogen Refuelling Station in Berlin. It presents a framework that can analyse an energy supply chain and at the same time enables easy reporting and presentation of various results...... by utilizing Dis-crete Event Simulation (DES). The industrial implication of this work is to provide practitioners with an anal-ysis framework for improved decision support. The novelty of this paper is the approach to model a supply chain together with a dynamically modelled event tree-based approach...

  19. A Robust Modular IGBT Power Supply for Magnetic Confinement Concepts

    Ziemba, Timothy; Miller, Ken; Carscadden, John; Prager, Jim


    Among current challenges in fusion science, and in particular within the Innovative Confinement Concepts (ICC) community, is the ability to generate increased power levels for pulsed magnets, arc plasma sources, radio frequency (RF) heating and current drive schemes at reasonable cost with current generation solid state devices. Continuous wave (CW) tube based power supplies are typically large and expensive, making them prohibitive for smaller experimental facilities or not cost effective when only pulsed input power is required. Next generation solid state power supplies could allow for multiple use applications with a single well developed module that can be easily reconfigured. As such, this type of robust power supply could be beneficial to several important fusion applications including high power RF heating and current drive schemes, high current pulsed magnets and plasma pre-ionization sources. Data will be presented on design characteristics and testing of a modular robust solid state power supply based on Insulate Gate Bi-polar Transistor (IGBT) technologies and developed by Eagle Harbor Technologies, INC. The modular power supply system can be assembled in multiple ways to address a wide range of applications and needs for the magnetic confinement community.

  20. Energy efficiency of computer power supply units - Final report

    Aebischer, B. [cepe - Centre for Energy Policy and Economics, Swiss Federal Institute of Technology Zuerich, Zuerich (Switzerland); Huser, H. [Encontrol GmbH, Niederrohrdorf (Switzerland)


    This final report for the Swiss Federal Office of Energy (SFOE) takes a look at the efficiency of computer power supply units, which decreases rapidly during average computer use. The background and the purpose of the project are examined. The power supplies for personal computers are discussed and the testing arrangement used is described. Efficiency, power-factor and operating points of the units are examined. Potentials for improvement and measures to be taken are discussed. Also, action to be taken by those involved in the design and operation of such power units is proposed. Finally, recommendations for further work are made.

  1. PTC thermistor protects multiloaded power supplies

    Leverone, H.; Mandell, N.


    A PTC /Positive-Temperature-Coefficient/ thermistor placed in series with each branch load of a multiload circuit prevents power loss in parallel branches. This thermistor may be used in any circuit requiring current limiting or intended overload resetting.

  2. Semiconductor power devices physics, characteristics, reliability

    Lutz, Josef; Scheuermann, Uwe; De Doncker, Rik


    Semiconductor power devices are the heart of power electronics. They determine the performance of power converters and allow topologies with high efficiency. Semiconductor properties, pn-junctions and the physical phenomena for understanding power devices are discussed in depth. Working principles of state-of-the-art power diodes, thyristors, MOSFETs and IGBTs are explained in detail, as well as key aspects of semiconductor device production technology. In practice, not only the semiconductor, but also the thermal and mechanical properties of packaging and interconnection technologies are esse

  3. Design and Construction of Low Cost High Voltage dc Power Supply for Constant Power Operation

    Kumar, N. S.; Jayasankar, V.


    Pulsed load applications like laser based systems need high voltage dc power supplies with better regulation characteristics. This paper presents the design, construction and testing of dc power supply with 1 kV output at 300 W power level. The designed converter has half bridge switched mode power supply (SMPS) configuration with 20 kHz switching. The paper covers the design of half bridge inverter, closed loop control, High frequency transformer and other related electronics. The designed power supply incorporates a low cost OPAMP based feedback controller which is designed using small signal modelling of the converter. The designed converter was constructed and found to work satisfactorily as per the specifications.

  4. Ensuring sustained ACT production and reliable artemisinin supply

    Olliaro Piero


    Full Text Available Abstract Introduction This paper reviews recent trends in the production, supply and price of the active ingredients as well as finished ACT products. Production and cost data provided in this paper are based on an ongoing project (Artepal. Stability data are derived from a development project on rectal artesunate. Discussion The artemisinin raw material and its derivatives appear to be very stable compared to the finished products. Supply of artemisinin changed in May 2004 when the Global Fund shifted financial support to qualified countries from chloroquine or sulphadoxine-pyrimethamine to an ACT for treatment of malaria. First, there was a sudden shortage of the starting material, and short term scarcity led to a steep rise in API price: it increased dramatically in 2004, from $350 per kg to more than $1000. Second, there was a parallel increase in the number of companies extracting artemisinin from 10 to 80 between 2003 and 2005 in China, and from 3 to 20 in Vietnam. Commercial cultivation began also in East Africa and Madagascar. A steady and predictable demand for the crop can eliminate such wide fluctuations and indirectly contribute to price stability of the herb, the API and ACT. With appropriate mechanisms to reduce those fluctuations, the cost of artemisinin might decrease sustainably to US$ 250–300 per kg. Conclusion Today the global health community is facing the risk of another cyclical swing with lower demand feeding into reduced planting of A. annua and, thereafter, a new shortage of the raw material and higher API prices. International donors, the largest purchasers for ACTs could better coordinate their activities, in order to guarantee purchase of ACTs and consequently of API with manufacturers. In parallel, the base of quality producers of APIs and finished ACT products needs to be broadened. While the ACT programme is still in its early stages, the consequences of another wave of artemisinin and ACT shortages would

  5. Constraining uncertainties in water supply reliability in a tropical data scarce basin

    Kaune, Alexander; Werner, Micha; Rodriguez, Erasmo; de Fraiture, Charlotte


    Assessing the water supply reliability in river basins is essential for adequate planning and development of irrigated agriculture and urban water systems. In many cases hydrological models are applied to determine the surface water availability in river basins. However, surface water availability and variability is often not appropriately quantified due to epistemic uncertainties, leading to water supply insecurity. The objective of this research is to determine the water supply reliability in order to support planning and development of irrigated agriculture in a tropical, data scarce environment. The approach proposed uses a simple hydrological model, but explicitly includes model parameter uncertainty. A transboundary river basin in the tropical region of Colombia and Venezuela with an approximately area of 2100 km² was selected as a case study. The Budyko hydrological framework was extended to consider climatological input variability and model parameter uncertainty, and through this the surface water reliability to satisfy the irrigation and urban demand was estimated. This provides a spatial estimate of the water supply reliability across the basin. For the middle basin the reliability was found to be less than 30% for most of the months when the water is extracted from an upstream source. Conversely, the monthly water supply reliability was high (r>98%) in the lower basin irrigation areas when water was withdrawn from a source located further downstream. Including model parameter uncertainty provides a complete estimate of the water supply reliability, but that estimate is influenced by the uncertainty in the model. Reducing the uncertainty in the model through improved data and perhaps improved model structure will improve the estimate of the water supply reliability allowing better planning of irrigated agriculture and dependable water allocation decisions.

  6. Market Design and Supply Security in Imperfect Power Markets

    Schwenen, Sebastian


    Supply security in imperfect power markets is modelled under different market designs. In a uniform price auction for electricity with two firms, strategic behaviour may leave firms offering too few capacities and unable to supply all realized demand. Market design that relies oncapacity markets...... increases available generation capacities for sufficiently high capacity prices and consequently decreases energy prices. However, equilibrium capacity prices are non-competitive. Capacity markets can increase security of supply, but cannot mitigate market power, which is exercised in the capacity market...

  7. The value of supply security The cost of power interruptions: Economic input for damage reduction and investment in networks

    de Nooij, M.; Koopmans, C.C.; Bijvoet, C.


    Most research into the reliability of electricity supply focuses on the suppliers. Reductions in the number of power interruptions will often be possible, but are often very costly. These costs will eventually be borne by electricity users. This paper studies the value of supply security in order to

  8. Study of selected problems of reliability of the supply chain in the trading company


    Full Text Available The paper presents the problems of the reliability of the supply chain as a whole in the dependence on the reliability of its elements. Different variants of reserving of canals (prime and reserve ones and issues connected with their switching are discussed.

  9. A Study on Management Techniques of Power Telecommunication System by Reliability Analysis

    Lee, B.K.; Lee, B.S.; Woy, Y.H.; Oh, M.T.; Shin, M.T.; Kwan, O.G. [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center; Kim, K.H.; Kim, Y.H.; Lee, W.T.; Park, Y.H.; Lee, J.J.; Park, H.S.; Choi, M.C.; Kim, J. [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of)


    Power telecommunication network is being increased rapidly in that expansion of power facilities according to the growth of electric power supply. The requirement of power facility and office automation and importance of communication services make it to complex and confusing to operate. And, for the sake of correspond to the change of power telecommunication network, effective operation and management is called for urgently. Therefore, the object of this study is to establish total reliability analysis system based on dependability, maintainability, cost effectiveness and replenishment for keep up reasonable reliability, support economical maintenance and reasonable planning of facility investment. And it will make effective management and administration system and schemes for total reliability improvement. (author). 44 refs., figs.

  10. Superficial Talk about Integration on Coal Mine Safety and Reliability of Power Supply to Coal Mine Production%浅谈整合煤矿供电安全可靠性对煤矿生产的影响



    煤矿是我国的重要能源,开采煤矿是提高我国经济效益的有效途径之一,而电是煤矿生产所必需的,所以,供电安全不但会对煤矿生产造成重要的影响,还会影响从事矿井生产的工作人员的人身安全。只有做好供电安全工作,才能为我国煤矿生产事业的发展奠定良好的基础。%Coal is the major energy, coal mining is one of the effective ways to improve the economic benefits of our country, and electricity is necessary for the production of coal mine, so security of supply would not only result in significant impact on coal production, also affect in mine production staff safety. Only do the job security of electricity supply in order to lay a good foundation for the development of China's coal mine industry.


    Sit M.


    Full Text Available The aim of the work is to develop the energy efficient schemes for energy supply of the industrial greenhouse designed for year-round production of plants that requires year-round maintenance of strongly prescribed temperature and humidity inside. We have been elaborated the complex "gas driven heat pump “water-air” – electric generator" (for use during the heating season as well as the "gas driven heat pump “water-air” – electric generator – desiccant – evaporative chiller" (for use during the off-season. Proposed structures have a high energetic and economic efficiency as compared with conventional schemes (boiler - chiller. The proposed complex ensures year-round maximum COP of heat pump and maximum performance of gas engine.

  12. Reliability-oriented energy storage sizing in wind power systems

    Qin, Zian; Liserre, Marco; Blaabjerg, Frede;


    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....

  13. Photovoltaic / Diesel / Battery Hybrid Power Supply System

    Tazvinga, Henerica


    Full Text Available electricity being allocated to the more important urban sector. The relatively low energy demand in rural areas does not compensate the cost of long-range transmission lines from the national grid. This justifies the use of more decentralised forms of power...

  14. Low power DCVSL circuits employing AC power supply


    In view of changing the type of energy conversion in CMOS circuits, this paper investigates low power CMOS circuit design, which adopts a gradually changing power clock. First, we discuss the algebraic expressions and the corresponding properties of clocked power signals. Then the design procedure is summed up for converting complementary CMOS logic gates employing DC power to the power-clocked CMOS gates employing AC power. On this basis, the design of differential cascode voltage switch logic (DCVSL) circuits employing AC power clocks is proposed. The PSPICE simulations using a sinusoidal power-clock demonstrate that the designed power-clocked DCVSL circuit has a correct logic function and low power characteristics. Finally, an interface circuit to convert clocked signals into the standard logic levels of a CMOS circuit is proposed, and its validity is verified by computer simulations.

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


    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.

  16. A flexible super-capacitive solid-state power supply for miniature implantable medical devices.

    Meng, Chuizhou; Gall, Oren Z; Irazoqui, Pedro P


    We present a high-energy local power supply based on a flexible and solid-state supercapacitor for miniature wireless implantable medical devices. Wireless radio-frequency (RF) powering recharges the supercapacitor through an antenna with an RF rectifier. A power management circuit for the super-capacitive system includes a boost converter to increase the breakdown voltage required for powering device circuits, and a parallel conventional capacitor as an intermediate power source to deliver current spikes during high current transients (e.g., wireless data transmission). The supercapacitor has an extremely high area capacitance of ~1.3 mF/mm(2), and is in the novel form of a 100 μm-thick thin film with the merit of mechanical flexibility and a tailorable size down to 1 mm(2) to meet various clinical dimension requirements. We experimentally demonstrate that after fully recharging the capacitor with an external RF powering source, the supercapacitor-based local power supply runs a full system for electromyogram (EMG) recording that consumes ~670 μW with wireless-data-transmission functionality for a period of ~1 s in the absence of additional RF powering. Since the quality of wireless powering for implantable devices is sensitive to the position of those devices within the RF electromagnetic field, this high-energy local power supply plays a crucial role in providing continuous and reliable power for medical device operations.

  17. Restructuring power supply in Germany; Umstrukturierung der Stromversorgung in Deutschland



    According to recent calculations of the Umweltbundesamt (Federal Environmental Office), all German nuclear power plants can be decommissioned from 2017. This will result neither in supply shortages nor in higher electricity rates, and Germany's climate protection goals will not be in danger either. There will be no need to import nuclear power from other countries. (orig.)




    Full Text Available In this paper, a three-phase on-lineuninterruptible power supply with reducednumber of switches topology is presented. The newtopology has less number of power electronicdevices as well as control functions. Differentoperating modes of the system are investigated aswell. Simulation and experimental results arepresented, which show the viability of the proposedtopology.

  19. Reliability Oriented Circuit Design For Power Electronics Applications

    Sintamarean, Nicolae Cristian

    . The temperature variation of the semiconductor devices plays a key role in the robustness design and reliability of power electronics converters. This factor has a major impact on the power converters used in renewable energy systems, like solar and wind energy applications, due to the fluctuating nature...... for improving the reliability is by active thermal control of the power electronic devices. The work developed during the Ph.D. studies the above mentioned topics, and is divided into two main parts: the first part develops a reliability-oriented design tool which is using a long term real-field mission......-profile as input and the second part propose an advanced gatedriver concept for enhancing the reliability of the power electronics devices. Chapter 1 introduce the emerging challenges of a design tool for reliability and which are the main methods for achieving active thermal control of the devices. To overcome...

  20. Optimizing efficiency on conventional transformer based low power AC/DC standby power supplies

    Nielsen, Nils


    This article describes the research results for simple and cheap methods to reduce the idle- and load-losses in very low power conventional transformer based power supplies intended for standby usage. In this case "very low power" means 50 Hz/230 V-AC to 5 V-DC@1 W. The efficiency is measured...... on two common power supply topologies designed for this power level. The two described topologies uses either a series (or linear) or a buck regulation approach. Common to the test power supplies is they either are using a standard cheap off-the-shelf transformer, or one, which are loss optimized by very...

  1. Seismic reliability assessment of electric power systems

    Singhal, A. [Stanford Univ., CA (United States); Bouabid, J. [Risk Management Solutions, Menlo Park, CA (United States)


    This paper presents a methodology for the seismic risk assessment of electric power systems. In evaluating damage and loss of functionality to the electric power components, fragility curves and restoration functions are used. These vulnerability parameters are extracted from the GIS-based regional loss estimation methodology being developed for the US. Observed damage in electric power components during the Northridge earthquake is used to benchmark the methodology. The damage predicted using these vulnerability parameters is found to be in good agreement with the damage observed during the earthquake.

  2. A novel testing approach for SSRF digital power supply controllers

    KE Xinhua; LU Songlin; LI Rui; XU Ruinian; SHEN Tianjian


    Digital power supply controller is one of the key parts of SSRF high resolution high stability magnet power supply system.It is very essential to keep any degradation of these excellent properties by any stages as small as possible via careful testing when the controller is developed.In this study,a novel testing approach was presented,with which a novel closed conrail loop without actual power converter was constructed,and the new developed SSRF Digital Controller can work well in it.

  3. High performance AC–DC control power supply for low voltage ride through inverters

    K Saichand; Akshay Kumrawat; Vinod John


    This paper presents a control power supply (CPS) design which is used to feed power to the subsystems of a power converter. The CPS design presented here maintains a constant 24Vdc output even over a wide (90Vrms to 270Vrms ) ac voltage variation at its input for a High Power Converter (HPC). The circuit design and closed loop control design of such a CPS are presented. During starting, the power supply to the control circuitry of the CPS in turn is obtained using a separate start-up power supply. The various design issues and details of the on-board power supply and start-up power circuit to ensure the reliable start-up and shut down of the CPS are analyzed. The CPS was tested for wide input voltage range (vin) and the performance validates the design. The CPS has also been tested for an input side voltage sag and its performance allows the HPC to meet the low voltage ride-through requirements.

  4. Very High Frequency Switch-Mode Power Supplies

    Madsen, Mickey Pierre

    The importance of technology and electronics in our daily life is constantly increasing. At the same time portability and energy efficiency are currently some of the hottest topics. This creates a huge need for power converters in a compact form factor and with high efficiency, which can supply...... these electronic devices. This calls for new technologies in order to miniaturize the power electronics of today. One way to do this is by increasing the switching frequency dramatically and develop very high frequency switch mode power supplies. If these converters can be designed to operate efficiently, a huge...... of technologies for very high frequency switch mode power supplies. At these highly elevated frequencies normal bulky magnetics with heavy cores consisting of rare earth materials, can be replaced by air core inductors embedded in the printed circuit board. This is investigated thoroughly and both spirals...

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

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


    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)

  6. A new topology and control method for electromagnetic transmitter power supplies

    Zhang, Yiming; Zhang, Jialin; Yuan, Dakang


    As essential equipment for electromagnetic exploration, electromagnetic transmitter reverse the steady power supply with desired frequency and transmit the power through grounding electrodes. To obtain effective geophysical data during deep exploration, the transmitter needs to be high-voltage, high-current, with high-accuracy output, and yet compact and light. The researches on the power supply technologies for high-voltage high-power electromagnetic transmitter is of significant importance to the deep geophysical explorations. Therefore, the performance of electromagnetic transmitter is mainly subject to the following two aspects: the performance of emission current and voltage, and the power density. These requirements bring technical difficulties to the development of power supplies. Conventionally, high-frequency switching power supplies are applied in the design of a high-power transmitter power supply. However, the structure of the topology is complicate, which may reduce the controllability of the output voltage and the reliability of the system. Without power factor control, the power factor of the structure is relatively low. Moreover high switching frequency causes high loss. With the development of the PWM (pulse width modulation) technique, its merits of simple structure, low loss, convenient control and unit power factor have made it popular in electrical energy feedback, active filter, and power factor compensation. Studies have shown that using PWM converters and space vector modulation have become the trend in designing transmitter power supply. However, the earth load exhibits different impedances at different frequencies. Thus ensuing high-accuracy and a stable output from a transmitter power supply in harsh environment has become a key topic in the design of geophysical exploration instruments. Based on SVPWM technology, an electromagnetic transmitter power supply has been designed and its control strategy has been studied. The transmitting

  7. Multi-reactor configurations for multi-megawatt spacecraft power supplies

    George, Jeffrey A.


    Several conceptual designs for a multimegawatt space nuclear power supply system were developed on the basis of hardware and technology from the existing multihundred kilowatt-class SP-100 reactor program. It is shown that net power outputs in the multimegawatt range can be achieved by using a modular multireactor configuration of several SP-100-derived nuclear power supplies. A variety of geometries were examined for their applicability to the multireactor configuration, showing that modular multireactor systems have the advantage of an increased redundancy in the power system, as compared with a single-reactor system, allowing higher reliabilities than those achievable with single-reactor systems. Results are presented on the Mars Cargo Mission analysis, showing that modularity allows the option of redeployment of power systems in Mars and facilitates refurbishment and turnaround of NEP transfer vehicles.

  8. Power Electronic Packaging Design, Assembly Process, Reliability and Modeling

    Liu, Yong


    Power Electronic Packaging presents an in-depth overview of power electronic packaging design, assembly,reliability and modeling. Since there is a drastic difference between IC fabrication and power electronic packaging, the book systematically introduces typical power electronic packaging design, assembly, reliability and failure analysis and material selection so readers can clearly understand each task's unique characteristics. Power electronic packaging is one of the fastest growing segments in the power electronic industry, due to the rapid growth of power integrated circuit (IC) fabrication, especially for applications like portable, consumer, home, computing and automotive electronics. This book also covers how advances in both semiconductor content and power advanced package design have helped cause advances in power device capability in recent years. The author extrapolates the most recent trends in the book's areas of focus to highlight where further improvement in materials and techniques can d...

  9. On the Ongoing Evolution of Very High Frequency Power Supplies

    Knott, Arnold; Andersen, Toke Meyer; Kamby, Peter


    in radio frequency transmission equipment helps to overcome those. However those circuits were not designed to meet the same requirements as power converters. This paper summarizes the contributions in recent years in application of very high frequency (VHF) technologies in power electronics, describes......The ongoing demand for smaller and lighter power supplies is driving the motivation to increase the switching frequencies of power converters. Drastic increases however come along with new challenges, namely the increase of switching losses in all components. The application of power circuits used...

  10. Unique Power Dense, Configurable, Robust, High-Voltage Power Supplies Project

    National Aeronautics and Space Administration — Princeton Power will develop and deliver three small, lightweight 50 W high-voltage power supplies that have a configurable output voltage range from 500 to 50 kVDC....

  11. Power Electronics and Reliability in Renewable Energy Systems

    Blaabjerg, Frede; Ma, Ke; Zhou, Dao


    Power Electronics are needed in almost all kind of renewable energy systems. It is used both for controlling the renewable source and also for interfacing to the load, which can be grid-connected or working in stand-alone mode. More and more efforts are put into making renewable energy systems...... better in terms of reliability in order to ensure a high availability of the power sources, in this case the knowledge of mission profile of a certain application is crucial for the reliability evaluation/design of power electronics. In this paper an overview on the power electronic circuits behind...... the most common converter configurations for wind turbine and photovoltaic is done. Next different aspects of improving the system reliability are mapped. Further on examples of how to control the chip temperature in different power electronic configurations as well as operation modes for wind power...

  12. Digital arc welding power supply based on real-time operating system


    A digital arc welding power supply was designed with the advanced reduced instruction set computer machine (ARM) and embedded real-time multi-task operating system micro C/OS-Ⅱ. The ARM, with its powerful calculating speed and complete peripheral equipments, is very suitable to work as the controller of the digital power supply. The micro C/OS-Ⅱ transplanted in ARM, helps to improve the respondent speed against various welding signals, as well as the reliability of the controlling software. The welding process consists of nine tasks. The tasks of great significance on reliability of the welder, for example, the A/D conversion of current and voltage, enjoy top priority. To avoid simultaneous-sharing on A/D converter and LCD module, two semaphores are introduced in to ensure the smooth performance of the welding power supply. Proven by experiments,the ARM and the micro C/OS-Ⅱ can greatly improve both the respondent speed and the reliability of the digital welder.

  13. Advanteges of using Two-Switch Forward in Single-Stage Power Factor Corrected Power Supplies

    Petersen, Lars


    A single-Stage power factor corrected power supply using a two-switch forward is proposed to increase efficiency. The converter is operated in the DCM (Discontinues Conduction Mode). This will insure the intermediate DC-bus to be controlled only by means of circuit parameters and therefore...... power supply has been implemented. The measured efficiency and power factor are about 87% and 0.96 respectively....

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

    Ma, Ke; Yang, Yongheng; Wang, Huai


    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...... and demonstrate how the power electronics is loaded under different stressors. Further, some systematic methods to design the power electronics technology for reliability will be given and demonstrated with two cases—one is a wind power and the other is photovoltaic application....

  15. Rethinking Rectification: AC-DC Power Supply in Package

    Pejtersen, Jens; Knott, Arnold; Jørgensen, Ivan Harald Holger

    Rectification of AC mains voltage is almost exclusively implemented with passive diode bridge rectifiers for power applications below 100 W. The diode bridge rectifier is reliable, cost effective and easy to use. But it is also lossy, nonlinear and passive. Thus reducing the power conversion...

  16. A Reliability-Oriented Design Method for Power Electronic Converters

    Wang, Huai; Zhou, Dao; Blaabjerg, Frede


    handbook) to the physics-of-failure approach and design for reliability process. A systematic design procedure consisting of various design tools is presented in this paper to design reliability into the power electronic converters since the early concept phase. The corresponding design procedures...

  17. A high-power switch-mode dc power supply for dynamic loads

    Shimer, D.W.; Lange, A.C. [Lawrence Livermore National Lab., CA (United States); Bombay, J.N. [Kaiser Engineers, Oakland, CA (United States)


    High-voltage dc power supplies are often required to operate with highly dynamic loads, such as arcs. A switch-mode dc power supply can offer significant advantages over conventional thyristor-based dc power supplies under such conditions. It can quickly turn off the supply to extinguish the arc, and it can quickly recover after the arc. It has a relatively small output filter capacitance, which results in small stored energy available to the arc. A 400-kW, 50-kV switch-mode dc power supply for an electron-beam gun that exploits these advantages was designed and tested. It uses four 100-kW, current-source-type dc-dc converters with inputs in parallel and outputs in series. The dc-dc converters operate at 20 kHz in the voltage regulator part and 10 kHz in the inverter, transformer, and output rectifier part of the circuit. Insulated gate bipolar transistors (IGBTs) are used as the power switches. Special techniques are used to protect the power supply and load against arcs and hard shorts. The power supply has an efficiency of 93%, an output voltage ripple of 1%, and fast dynamic response. In addition, it is nearly one-third the size of conventional power supplies.

  18. Conducted EMI Suppression in Plasma Cutting Power Supply

    Abdolreza Esmaeli; Sun Li; Zhao Ke


    A systematic approach to the design of the conducted electromagnetic interference (EMI) filter of high-density plasma cutting power supply has been developed. Converter components have been accurately modeled, with parasitic elements extracted to reveal their impacts on the EMI noises. Circuit simulations have been used to analyze and minimize the EMI noises.Conducted EMI noise measurement and filter design of this power supply have been achieved which successfully satisfy the FCC class B limits in the frequency range from 150 kHz to 30 MHz.The analyses and experimental results show that the designed filter guarantees that the required attenuation will be achieved.

  19. RFX machine and power supply improvements for RFP advanced studies

    Piovan, R. E-mail:; Gnesotto, F.; Ortolani, S.; Baker, W.; Barana, O.; Bettini, P.; Cavazzana, R.; Chitarin, G.; Dal Bello, S.; De Lorenzi, A.; Fiorentin, P.; Gaio, E.; Grando, L.; Luchetta, A.; Manduchi, G.; Marchiori, G.; Marcuzzi, D.; Masiello, A.; Milani, F.; Peruzzo, S.; Pomaro, N.; Sonato, P.; Taliercio, C.; Toigo, V.; Zaccaria, P.; Zanotto, L.; Zollino, G


    Experimental results and theoretical studies call for Reversed Field Experiment (RFX) machine and power supply improvements to allow studies that go beyond those of a conventional Reversed Field Pinch (RFP) with passively stabilized turbulent MHD dynamo. The new paths opened by recent results in RFX and other RFP machines are introduced; then the goals and the design lines of the technical modifications of RFX, mainly addressed to improve the first wall, the plasma magnetic boundaries and to increase the operational flexibility of the toroidal field circuit power supply, are reported.

  20. Analysis and design of over-current limit control strategies applied in aeronautical power supplies

    WANG Lin-bing; HE Xiang-ning


    Some Over-Current Limit Control strategies are analyzed and designed to meet the demands of high reliability and rapid dynamic response in the aeronautical power supply applications. The control schemes are both effective in DC-DC converters and DC-AC converters. Controller models are set up, and the over-current limit operation principles of analogy and digital control are analyzed too. An 800VA aeronautical power supply has been constructed to verify the performance of the proposed control strategy in various cases such as the sudden load change and the constant load. The analysis and experiments confirm the advantages of the proposed over-current limit strategies as follows: simple,effective and reliable.

  1. PEP-II Large Power Supplies Rebuild Program at SLAC

    de Lira, Antonio C; Lipari, James J; da Silva Rafael, Fernando


    At PEP-II, seven large power supplies (LGPS) are used to power quad magnets in the electron-positron collider region. The LGPS ratings range from 72kW to 270kW, and were installed in 1997. They are unipolar off-line switch mode supplies, with a 6 pulse bridge rectifying 480VAC, 3-phase input power to yield 650VDC unregulated. This unregulated 650VDC is then input into one (or two) IGBT H-bridges, which convert the DC into PWM 16 kHz square wave AC. This high frequency AC drives the primary side of a step-down transformer followed by rectifiers and low pass filters. Over the years, these LGPS have presented many problems mainly in their control circuits, making it difficult to troubleshoot and affecting the overall accelerator availability. A redesign/rebuilding program for these power supplies was established under the coordination of the Power Conversion Department at SLAC. During the 2004 accelerator summer shutdown all the control circuits in these supplies were redesigned and replaced. A new PWM control b...

  2. Development of a heavy duty portable variable power supply (HPVPS)

    Musa, Ahmad Zulfadli Bin; Lung, Chong Man; Abidin, Wan'Amirah Basyarah Binti Zainol


    This paper covers the innovation of a Heavy Duty Portable Variable Power Supply (HPVPS) in Jabatan Kejuruteraan Elektrik (JKE), Politeknik Mukah, Sarawak (PMU). This project consists of variable power supply which can vary the output from 1.2 V to 11.6V, AC pure wave inverter to convert DC to AC for the operation of low power home appliances and also used Li-on rechargeable batteries to store the electrical energy and additional feature that can be used to jump-start the batteries of the car. The main objective of this project is to make the user can operate the electronic devices anywhere whenever if no electricity while doing their lab activities. Most of the regulated power supply in JKE lab aged 9-10 years old and need periodical maintenance and need cost and also the unit can be used is not enough to support the whole class during lab activities. As a result, the P&P process will be facing the major problem in order to make the lab activities running smoothly. By development of the portable variable power supply, the P&P process is more efficient and very helpful.

  3. Power system reliability enhancement by using PowerformerTM

    Rahmat-Allah Hooshmand


    Full Text Available A high-voltage generator PowerformerTM is a new generation of the AC generators. The most significant advantages of these PowerformerTM are their direct connection to high-voltage grid, higher availability, and more reactive power margin, short term overloading capacity and removing the power transformer from the structure of the power plant. In this paper, the installation effect of these generators on the power system reliability is investigated. The amount of the effects depends on the type and location of the power plant, location of the PowerformerTM, the size of load and network topology. For this purpose, in the 6-bus IEEE RBTS system, the conventional generators are replaced by these new PowerformerTM and then, the reliability indices are evaluated. The simulation results show that the reliability indices such as the expected duration of load curtailment (EDLC and the expected energy not served (EENS are improved. .

  4. Power quality improvement in switched mode power supplies using ...


    A SEPIC stores the energy in an inductor, and transfers that energy to the output storage capacitor. ..... 2011–2017. ... His areas of interest include power electronics, electrical machines and drives, renewable energy systems, active filters, ...

  5. Designing a Power Supply with Multiple Input Options


    Some electronic systems such as field communications equip-ment must be able to operate from a variety of power sources,forexample,worldwide universal AC (85—264V rms) or vehicle bat-tery power. These systems may also require backup power in casethe primary source is interrupted.The illustration shows a power supply that can operate fromthe AC line,from a 12V or 24V vehicle battery,or from an internal48V backup battery. For AC line use, a front end module accepts a

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

    Ma, Ke; Yang, Yongheng; Wang, Huai


    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. Research for the Cable Layout Way of the Bypass Operation System in Agricultural Power Supply Network

    Niu, Jie; Li, Jinliang; Zou, Dehua; Yang, Qi; Li, Xu; Yan, Yu; Li, Tang


    Non-blackout working of agricultural power supply network is significant to shorten the outage time, decrease the outage loss, and improve the supply reliability and safety. It is impossible to hang the wire rope first and then suspend the cable because of the poor bearing ability of the pole in agricultural power supply network. A kind of new cable arrangement way, its matching tools and the flexible cable that can bear the tension by itself are needed to be put forward and developed. It is necessary to calculate the electric field intensity of the flexible cable to verify that the electric field intensity meets the insulation demand. In this new design, the fiber layer is added into the flexible cable and its maximum tension force is measured to reach to 4000 N. Based on the features of live working in the agricultural power supply network, the new layout way of the cable is proposed; the matching tools and the new flexible cable that can bear the tension by itself are developed as well in this paper. All of the research achievements can give references for the live working of the agricultural power supply network.

  8. Development of a solar charged laboratory bench power supply

    Ayara, W. A.; Omotosho, T. V.; Usikalu, M. R.; Singh, M. S. J.; Suparta, W.


    This product is an improvement on available DC laboratory bench power supply. It is capable of delivering low voltage Alternating Current (AC) and Direct Current (DC) to carry out basic laboratory experiment for both secondary schools and also at higher education institutions. The power supply is capable of delivering fixed DC voltages of 5V, 9V, 12V, variable voltage of between 1.25-30V and a 12V AC voltage. Also Incorporated is a USB port that allows for charging cell phones and other mobile devices, and a dedicated 12V DC output to power 5-7 Watt LED bulb to provide illumination in the laboratory for the instructor who may need to work at night in the absence of utility power.

  9. Bimode uninterruptible power supply compatibility in renewable hybrid energy systems

    Bower, W. (Sandia National Labs., Albuquerque, NM (USA)); O' Sullivan, G. (Abacus Controls, Inc., Somerville, NJ (USA))


    Inverters installed in renewable hybrid energy systems are typically used in a stand-alone mode to supply ac power to loads from battery storage when the engine-generator is not being used. Similarities in topology and in the performance requirements of the standby uninterruptible power supply (UPS) system and the hybrid system suggest the UPS could be used in hybrid energy systems. Another alternative to inverters with add-on charging circuits or standby UPS hardware is the Bimode UPS. The bimode UPS uses common circuitry and power components for dc to ac inversion and battery charging. It also provides an automatic and nearly instantaneous ac power transfer function when the engine-generator is started or stopped. The measured operating and transfer characteristics of a bimode UPS in a utility system and in a hybrid system are presented. The applicability of the bimode UPS to hybrid systems and its compatibility in a PV/engine-generator hybrid system are given.

  10. Dual Power Supplies for PEP-II Injection Kickers

    Olszewski, J; Decker, F.-J.; Iverson, R.H.; Kulikov, A.; Pappas, C.; /SLAC


    Originally the PEP-II injection kickers were powered by one power supply. Since the kicker magnets where not perfectly matched, the stored beam got excited by about 7% of the maximum kicker amplitude. This led to luminosity losses which were especially obvious for trickle injection when the detector is on for data taking. Therefore two independent power supplies with thyratrons in the tunnel next to the kicker magnet were installed. This also reduces the necessary power by about a factor of four since there are no long cables that have to be charged. The kickers are now independently adjustable to eliminate any non-closure of the kicker system and therefore excitation of the stored beam. Setup, commissioning and fine tuning of this system are discussed.

  11. Milliwatt radioisotope power supply for the PASCAL Mars surface stations

    Allen, Daniel T.; Murbach, Marcus S.


    A milliwatt power supply is being developed based on the 1 watt Light-Weight Radioisotope Heater Unit (RHU), which has already been used to provide heating alone on numerous spacecraft. In the past year the power supply has been integrated into the design of the proposed PASCAL Mars Network Mission, which is intended to place 24 surface climate monitoring stations on Mars. The PASCAL Mars mission calls for the individual surface stations to be transported together in one spacecraft on a trajectory direct from launch to orbit around Mars. From orbit around Mars each surface station will be deployed on a SCRAMP (slotted compression ramp) probe and, after aerodynamic and parachute deceleration, land at a preselected location on the planet. During descent sounding data and still images will be accumulated, and, once on the surface, the station will take measurements of pressure, temperature and overhead atmospheric optical depth for a period of 10 Mars years (18.8 Earth years). Power for periodic data acquisition and transmission to orbital then to Earth relay will come from a bank of ultracapacitors which will be continuously recharged by the radioisotope power supply. This electronic system has been designed and a breadboard built. In the ultimate design the electronics will be arrayed on the exterior surface of the radioisotope power supply in order to take advantage of the reject heat. This assembly in turn is packaged within the SCRAMP, and that assembly comprises the surface station. An electrically heated but otherwise prototypical power supply was operated in combination with the surface station breadboard system, which included the ultracapacitors. Other issues addressed in this work have been the capability of the generator to withstand the mechanical shock of the landing on Mars and the effectiveness of the generator's multi-foil vacuum thermal insulation. .

  12. Highly efficient welding power supply. Final report, May 1, 1978-September 30, 1980

    Thommes, J M


    The results and findings of an energy efficient welding power development project are presented. The power source developed is to be used for electric arc welding processes in which 3.5 trillion Btu of energy (1978 example year) can be saved annually. The power source development incorporates the use of switch mode power supply techniques in order to convert industrial supply mains (230/460 VAC 3 phi 60 Hz) to appropriate welding voltages and currents (up to 32 volts/up to 300 amps). A series capacitor switch mode power circuit was the circuit technique chosen in order to optimize energy efficiency, costs, reliability, size/weight, and welding performance. Test results demonstrated an effective efficiency (taking into account idle power consumption) of 80 to 91% for the energy efficient power source while the conventional types of power sources tested ranged from 41 to 74% efficiency. Line power factor was also improved for the energy efficient power source. Field tests indicated additional refinements of weld process performance and power source audible noise emission reduction could be beneficial.

  13. A High Power Test Method for Pattern Magnet Power Supplies with Capacitor Banks

    Kurimoto, Yoshinori; Morita, Yuichi; Sagawa, Ryu; Shimogawa, Tetsushi; Miura, Kazuki

    In the J-PARC Main Ring (MR), we plan to increase the beam intensity from 230 to 750 kW. To achieve this, the synchrotron repetition period must be shortened from 2.48 s to approximately 1 s using new power supplies for the main magnets. We are currently researching and developing new power supplies with large capacitor banks. Such banks are needed to reduce the power variation at the main grid in the J-PARC site for future operations with shorter repetition periods. However, it is very difficult to test the new power supplies at their rated power before installation. This is because the power handled by the power supplies used for the J-PARC MR main magnets is too high to be tested in factories or laboratories. To overcome this problem, we suggest a test method involving the use of two capacitor banks. In this method, two power supplies and a small inductive load are connected between two capacitor banks. By controlling the energy flow between the two capacitor banks in this setup, the received power and inductive load can be kept very small. This article describes the details of the control method and the results of the test experiment using a mini-model power supply.

  14. Minimizing the mass of a potential railgun power supply

    Johnson, D.E.; Noel, A.P.; Clements, W.D. (IAP Research, Inc., Dayton, OH (United States))


    This paper reports on the design of a pulsed power supply to deliver 5 MJ at 1 MA at 1 shot per second to a railgun. The supply stores energy at low current in the primary of the hydrogen-cooled transformer. A switch opens the primary circuit to transfer energy to the secondary, stepping the current up to 1 MA. The authors are studying the relationship between the transformer and switch to determine how the total power supply mass can be minimized. Vacuum interrupters and gate-turn-off thyristors are used in the switch. Switch mass dominates the system, accounting for 85% of the total mass. The switch must absorb the uncoupled energy of the transformer. Low transformer coupling requires large capacitors. Even with high coupling, capacitors account for 75 to 85% of the switch mass. If transformer coupling increases, the uncoupled energy decreases, resulting in low capacitor mass.

  15. Development of Discrete Power Supply with Charge Pump Method for High Powered Sonar System

    Kristian Ismail


    Full Text Available Power supply is one of the electronic devices that can provide electric energy for electronic systems or other systems. There are several types of power supplies that can be applied depend on the requirement and functions. One example is the use of power supply for sonar systems. Sonar system is a device which can be used to detect a target under water. The sonar system is an electronic circuit that requires a power supply with specific characteristics when the sonar functions as a transmitter and a receiver in the specific span time (when on and the specific lag time (when off. This paper discusses the design of power supply for high-powered sonar systems with discrete methods in which high power supply is only applied when the acoustic waves radiated under water. Charge pump was used to get the appropriate output voltage from lower input voltage. Charge pump utilized a combination of series and parallel connections of capacitors. The working mode of this power supply used the lag time as the calculation of time to charge charge pump capacitors in parallel while the span time was used for the calculation of discharging the charge pump capacitors in series.

  16. Windfarm generation assessment for reliability analysis of power systems

    Negra, N.B.; Holmstrøm, O.; Bak-Jensen, B.;


    Due to the fast development of wind generation in the past ten years, increasing interest has been paid to techniques for assessing different aspects of power systems with a large amount of installed wind generation. One of these aspects concerns power system reliability. Windfarm modelling plays...

  17. Design of Controller for New EAST Fast Control Power Supply

    HUANG Haihong; YIN Ming; WANG Haixin


    The effectiveness of the magnetic confinement of plasma can be improved by elongating the plasma cross-section in tokamak devices.But elongated plasma has vertical displacement instability,so a feedback control system is needed to restrain the plasma's vertical displacement.A fast control power supply is needed to excite the active feedback coils,which produces a magnetic field to control the plasma's displacement.With the development of EAST,the fast control power supply needs to keep on enhancing the fast response and output current.The structure of a new power supply is introduced in this paper.The method of multiple inverters paralleled with the current sharing reactor is presented to meet the need for large current and fast control.According to the design demands of the EAST fast control power supply,the adjuster of the current close loop is applied to the inverter,which can advance its ability to restrain the loop current in low frequency and DC output.The result of the experiment confirms the validity of the proposed scheme and control strategy.

  18. 47 CFR 80.860 - Reserve power supply.


    .... (f) The cooling system of each internal combustion engine used as a part of the reserve power supply... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Technical Equipment Requirements for Cargo Vessels Not Subject to Subpart W §...

  19. A cascaded online uninterruptible power supply using reduced semiconductor

    Zhang, Lei; Loh, Poh Chiang; Gao, Feng


    A cascaded online uninterruptible power supply (UPS) is proposed here that uses 25% lesser semiconductor, as compared to its traditional H-bridge cascaded precedence. Unlike other component-saving configurations where compromises are unavoidable, almost no performance degradations and constraints...

  20. Operation reliability analysis of independent power plants of gas-transmission system distant production facilities

    Piskunov Maksim V.


    Full Text Available The new approach was developed to analyze the failure causes in operation of linear facilities independent power supply sources (mini-CHP-plants of gas-transmission system in Eastern part of Russia. Triggering conditions of ceiling operation substance temperature at condenser output were determined with mathematical simulation use of unsteady heat and mass transfer processes in condenser of mini-CHP-plants. Under these conditions the failure probability in operation of independent power supply sources is increased. Influence of environmental factors (in particular, ambient temperature as well as output electric capability values of power plant on mini-CHP-plant operation reliability was analyzed. Values of mean time to failure and power plant failure density during operation in different regions of Eastern Siberia and Far East of Russia were received with use of numerical simulation results of heat and mass transfer processes at operation substance condensation.

  1. Reliability modeling and analysis of smart power systems

    Karki, Rajesh; Verma, Ajit Kumar


    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

  2. Seismic reliability analysis of large electric power systems

    何军; 李杰


    Based on the De. Morgan laws and Boolean simplification, a recursive decomposition method is introduced in this paper to identity the main exclusive safe paths and failed paths of a network. The reliability or the reliability bound of a network can be conveniently expressed as the summation of the joint probabilities of these paths. Under the multivariate normal distribution assumption, a conditioned reliability index method is developed to evaluate joint probabilities of various exclusive safe paths and failed paths, and, finally, the seismic reliability or the reliability bound of an electric power system.Examples given in thc paper show that the method is very simple and provides accurate results in the seismic reliability analysis.

  3. Essays in market power mitigation and supply function equilibrium

    Subramainam, Thiagarajah Natchie

    Market power mitigation has been an integral part of wholesale electricity markets since deregulation. In wholesale electricity markets, different regions in the US take different approaches to regulating market power. While the exercise of market power has received considerable attention in the literature, the issue of market power mitigation has attracted scant attention. In the first chapter, I examine the market power mitigation rules used in New York ISO (Independent System Operator) and California ISO (CAISO) with respect to day-ahead and real-time energy markets. I test whether markups associated with New York in-city generators would be lower with an alternative approach to mitigation, the CAISO approach. Results indicate the difference in markups between these two mitigation rules is driven by the shape of residual demand curves for suppliers. Analysis of residual demand curves faced by New York in-city suppliers show similar markups under both mitigation rules when no one supplier is necessary to meet the demand (i.e., when no supplier is pivotal). However, when some supplier is crucial for the market to clear, the mitigation rule adopted by the NYISO consistently leads to higher markups than would the CAISO rule. This result suggest that market power episodes in New York is confined to periods where some supplier is pivotal. As a result, I find that applying the CAISOs' mitigation rules to the New York market could lower wholesale electricity prices by 18%. The second chapter of my dissertation focuses on supply function equilibrium. In power markets, suppliers submit offer curves in auctions, indicating their willingness to supply at different price levels. Although firms are allowed to submit different offer curves for different time periods, surprisingly many firms stick to a single offer curve for the entire day. This essentially means that firms are submitting a single offer curve for multiple demand realizations. A suitable framework to analyze

  4. Comparison of strategies of preventive and corrective maintenance of uninterruptible power supply

    B. Y. Volochiy


    Full Text Available Introduction. The comparison of the reliability of two variants of the fault-tolerant N+M redundant configurations for uninterruptible power supply with corrective and preventive maintenance is given in this paper. Formulation of the problem. Different variants of fault-tolerant redundant configurations and maintenance strategies provide equivalent mean time to failure indexes, but at the same time have different values of the probability of failure-free operation at given operation time value. Description of object under consideration. Fault-tolerant system consists of main and hot reserve modules and has two accumulator batteries. Reliability model for fault-tolerant system with N+M redundant configuration. Carrying out this research was made possible after the development of models of fault-tolerant systems as Kolmogorov - Chapman differential equation systems. Comparison of the reliability of uninterruptible power supply with different fault-tolerant configurations. There is shown quantitative difference between reliability indexes (operation time where probability of failure-free operation is not less than 0.99 of corrective and preventive maintenance. Conclusions. Reliability analysis of fault-tolerant systems shows that the strategy of corrective maintenance has higher values of operation time where probability of failure-free operation is not less than 0.99.

  5. Power supply system for negative ion source at IPR

    Gahlaut, Agrajit; Sonara, Jashwant; Parmar, K G; Soni, Jignesh; Bandyopadhyay, M; Singh, Mahendrajit; Bansal, Gourab; Pandya, Kaushal; Chakraborty, Arun, E-mail: agrajit@ipr.res.i [Institute for Plasma Research, Gandhinagar, Gujarat - 382428 (India)


    The first step in the Indian program on negative ion beams is the setting up of Negative ion Experimental Assembly - RF based, where 100 kW of RF power shall be coupled to a plasma source producing plasma of density {approx}5 x 10{sup 12} cm{sup -3}, from which {approx} 10 A of negative ion beam shall be produced and accelerated to 35 kV, through an electrostatic ion accelerator. The experimental system is modelled similar to the RF based negative ion source, BATMAN presently operating at IPP, Garching, Germany. The mechanical system for Negative Ion Source Assembly is close to the IPP source, remaining systems are designed and procured principally from indigenous sources, keeping the IPP configuration as a base line. High voltage (HV) and low voltage (LV) power supplies are two key constituents of the experimental setup. The HV power supplies for extraction and acceleration are rated for high voltage ({approx}15 to 35kV), and high current ({approx} 15 to 35A). Other attributes are, fast rate of voltage rise (< 5ms), good regulation (< {+-}1%), low ripple (< {+-}2%), isolation ({approx}50kV), low energy content (< 10J) and fast cut-off (< 100{mu}s). The low voltage (LV) supplies required for biasing and providing heating power to the Cesium oven and the plasma grids; have attributes of low ripple, high stability, fast and precise regulation, programmability and remote operation. These power supplies are also equipped with over-voltage, over-current and current limit (CC Mode) protections. Fault diagnostics, to distinguish abnormal rise in currents (breakdown faults) with over-currents is enabled using fast response breakdown and over-current protection scheme. To restrict the fault energy deposited on the ion source, specially designed snubbers are implemented in each (extraction and acceleration) high voltage path to swap the surge energy. Moreover, the monitoring status and control signals from these power supplies are required to be electrically ({approx} 50k


    Oleg Borisovich Shonin


    Full Text Available The paper deals with one of the important ecological problems – utilization of associated petroleum gas (APG at oil fields. An example of APG usage as a fuel for gas turbine power plants is examined. Among possible topologies of power plants the focus is put on the structure based on turbines with combined diesel-gas supplying for increasing in reliability of power generation in case of failures in the system of preparation of APG. In order to ensure correct transition of turbines from gas to diesel supplying it is important to know responds of the system to the interruption of gas supplying. Based on the fundamental principles of thermodynamics and fluid dynamics gas-turbine power plant simulation model has been developed utilizing MATLAB/Simulink environment. Using the model has allowed revealing the influence of load-sharing among the turbines of different types on the transition to an additional source of turbine fuel. Based on simulation results, recommendations have been worked out for the improvement of the reliability of gas turbine power plant.

  7. Distributed Measuring System for Predictive Diagnosis of Uninterruptible Power Supplies in Safety-Critical Applications

    Sergio Saponara


    Full Text Available This work proposes a scalable architecture of an Uninterruptible Power Supply (UPS system, with predictive diagnosis capabilities, for safety critical applications. A Failure Mode and Effect Analysis (FMEA has identified the faults occurring in the energy storage unit, based on Valve Regulated Lead-Acid batteries, and in the 3-phase high power transformers, used in switching converters and for power isolation, as the main bottlenecks for power system reliability. To address these issues, a distributed network of measuring nodes is proposed, where vibration-based mechanical stress diagnosis is implemented together with electrical (voltage, current, impedance and thermal degradation analysis. Power system degradation is tracked through multi-channel measuring nodes with integrated digital signal processing in the transformed frequency domain, from 0.1 Hz to 1 kHz. Experimental measurements on real power systems for safety-critical applications validate the diagnostic unit.

  8. Overview on the power supply systems for plasma instabilities control

    Toigo, V., E-mail: [Consorzio RFX - EURATOM - ENEA Association, Stati Uniti 4, 35127 Padova (Italy); Gaio, E.; Piovan, R.; Barp, M.; Bigi, M.; Ferro, A.; Finotti, C.; Novello, L.; Recchia, M.; Zamengo, A.; Zanotto, L. [Consorzio RFX - EURATOM - ENEA Association, Stati Uniti 4, 35127 Padova (Italy)


    The paper presents an overview on the power supply (PS) systems for plasma instabilities control in fusion experiments, based on active control coils. First, the MHD instabilities and the approach to their control in Tokamaks and Reversed Field Pinches (RFPs) are described. Then, the features of MHD modes controls presently used in fusion experiments are reviewed. For the control systems based on active coils fed by fast power supplies, the typical requirements in terms of power, dynamics, accuracy and delay are summarized and discussed. Then, a survey on the technology available to design these types of PSs is given, together with the most suitable circuit topologies and guidelines for the design, on the basis of solutions adopted in existing experiments.

  9. Energy efficiency criteria in uninterruptible power supply selection

    Moreno-Munoz, A.; Flores-Arias, J.M.; Bellido-Outerino, F.J.; Gil-de-Castro, A. [Universidad de Cordoba, Area de Electronica, Escuela Politecnica Superior, Leonardo Da Vinci Bldg., Campus de Rabanales, Ctra. Nacional IV, Km 369, E-14071 Cordoba (Spain); Rosa, Juan Jose Gonzalez de la [Universidad de Cadiz, Area de Electronica, Dpto. ISA, TE y Electronica, Escuela Politecnica SuperiorAvda, Ramon Puyol, S/N, E-11202 Algeciras-Cadiz (Spain)


    With the generalized use of microelectronic devices, server computers and other susceptible equipment, the subject related to power quality (PQ) and its relationship to vulnerability of high performance plants are becoming an increasing concern to the industry. This paper addresses how uninterruptible power supply (UPS), particularly when configured in distributed DC mode, can become an energy efficient (EE) solution in high-tech buildings, especially when integrated with complimentary PQ measures. The paper is based on PQ audits conducted at different high-tech industries over the last years. It was found that the main problems for the equipment installed were voltage sags (or dips). Among all categories of electrical disturbances, voltage sags and momentary interruptions are the nemeses of the automated industrial process. The paper analyzes the capabilities of modern electronic power supplies and the convenience of embedded solution. Finally it is addresses the role of the Standards on the protection of electronic equipment and the implications for the final costumer. (author)

  10. Analysis of heat transfer in portable power supply

    Abdullah, Mohd Azman; Ali, Ahmad Nazrin


    Portable power supply (PPS) is developed based on the necessity in supplying instant power to support domestic appliances during power shortage or in remote area. In this paper, the heat transfer inside the PPS is analyzed and demonstrated by temperature change during battery charging and discharging. The computational fluid dynamic (CFD) model of the PPS battery and housing are developed. The heat flow inside the PPS is studied at different conditions of battery and air flows. The increment of the temperature inside the PPS could cause the PPS system to damage and unsafe. Few elements are manipulated for the study, such as battery positions, holedimensions and fan models in order toimprove the design of PPS. Experimental approach is also conducted to validate the temperature and heat transfer in the PPS.

  11. Active Power Flow Optimization of Industrial Power Supply with Regard to the Transmission Line Conductor Heating

    Leyzgold D.Yu.


    Full Text Available This article studies the problem of the transmission line conductor heating effect on the active power flows optimization in the local segment of industrial power supply. The purpose is to determine the optimal generation rating of the distributed power sources, in which the power flow values will correspond to the minimum active power losses in the power supply. The timeliness is the need to define the most appropriate rated power values of distributed sources which will be connected to current industrial power supply. Basing on the model of active power flow optimization, authors formulate the description of the nonlinear transportation problem considering the active power losses depending on the transmission line conductor heating. Authors proposed a new approach to the heating model parameters definition based on allowable current loads and nominal parameters of conductors as part of the optimization problem. Analysis of study results showed that, despite the relatively small active power losses reduction to the tune 0,45% due to accounting of the conductors heating effect for the present configuration of power supply, there are significant fluctuations in the required generation rating in nodes of the network to 9,32% within seasonal changes in the outer air temperature. This fact should be taken into account when selecting the optimum power of distributed generation systems, as exemplified by an arbitrary network configuration.

  12. Regulation by incentives of power supply grids; Die Anreizregulierung der Energieversorgungsnetze

    Hardach, Felix


    Since 1 January 2009, a system of regulation by incentives governs the access to the German electricity and gas grids. The system is to induce grid owners to reduce the cost of power and gas transmission and to lower the electricity and gas rates charged to end users. This will protect end users from the negative effects of power and gas supply monopolies. Potential negative effects of regulation by incentives, on the other hand, are reduced reliability of supply and excessive demands on power and gas grid owners. The new legal fundamentals of regulation by incentives as in Section 21a EnWG and ARegV raise many legal questions, e.g. concerning the interpretation of the standards and their integration in the existing boundary conditions set by German constitutional and administrative law.

  13. Proposal for the award of a contract for the supply of uninterruptible power supplies for the Computer Centre


    This document concerns the award of a contract for the supply of uninterruptible power supplies (UPS) for the Computer Centre. The Finance Committee is invited to agree to the negotiation of a contract with MGE-UPS (FR), the lowest bidder, for the supply of uninterruptible power supplies for the Computer Centre for a total amount of 527 661 euros (818 714 Swiss francs), not subject to revision. The rate of exchange used is that stipulated in the tender.




    Full Text Available The history of water supply and distribution is as old as the history of civilization. In the present society, water supply system has become an important and necessary element. It also gives an indication of level of advancement of society. Water Distribution Network (WDN is an important component of water supply system which contributes to nearly 70% of the total cost. Optimal design of water distribution network is the aim of any agency dealing with water supply distribution. Consideration of reliability in water istribution networks has been received increasing attention over the past few years. In the present research work, the main focus is onto develop a new parameter for assessing the overall network reliability using fuzzy logic concepts based on the excess pressures available at the demand nodes and to be incorporated in the optimal design and to incorporate this parameter in a two objective optimization model for design of water distribution network using the combination of Genetic Algorithms and EPANET tool kit in the MATLABenvironment.The best range of excess of minimum residual pressures is considered in the present study in such a way that the reliability of the network is maximum. The proposed methodology is applied on a two loop gravity network which is referred by most of the researchers. 54optimal solutions are identified for the network. The Network Reliability Parameter (NRP, Cost Reliability Ration (CRR and Cost per Unit Reliability and Unit Length (CURUL parameters are used to compare the results with the previous researchers. It is found that the present study shows better results of when comparing withthe results of the previous researchers.

  15. Reducing Conductor Usage in Superconducting Machines by Multiple Power Supplies

    Jensen, Bogi Bech; Mijatovic, Nenad; Abrahamsen, Asger Bech


    This paper presents and applies a method of reducing the needed amount of superconductor in a superconducting machine by supplying the superconductor from multiple power supplies. The method is presented and validated experimentally in a constructed prototype. Thereafter, a superconducting tape...... is tested experimentally for allowable current density in a flux density spanning from 0 to 16 T and a temperature range from 5 K to 85 K. Using the experimental data from the superconductor, the proposed method is applied to minimize the usage of superconductor in a 10-MW superconducting direct drive wind...

  16. Load supply reliability evaluation applied to the house load of Itaipu power plant - a post operation analysis for the year 1992; A confiabilidade operativa de atendimento a carga da usina de Itaipu 50 Hz no ano de 1992 - uma avaliacao pos-operativa

    Silva, Rui J.G.C.; Almeida, Marcelino P. [Itaipu Binacional, Foz do Iguacu, PR (Brazil)


    This work presents the statistics of the 50 Hz Itaipu hydroelectric power plant in the 1992, under the aspect operative spinning reserve, comparing it with the obtained results through of the calculus of the operative reliability. (author) 7 refs.

  17. Remote power supply by wind/diesel/battery systems - operational experience and economy

    Kniehl, R. [CES - Consulting and Engineering Services, Heidelberg (Germany); Cramer, G.; Toenges, K.H. [SMA Regelsysteme GmbH, Niestetal (Germany)


    To continuously supply remote villages and settlements not connected to the public grid with electric power is an ambitious technical task considering ecological and economical points of view. The German company SMA has developed a modular supply system as a solution for this task in the range of 30 kW to 5 MW. Meanwhile more than 20 applications of these `Intelligent Power Systems (IPS)` have proved their technical reliability and economical competitiveness worldwide under different, and also extreme environmental conditions. Actually it is the first commercially available advanced Wind/Diesel/Battery System for remote area electrification. The modular autonomous electric supply systems realized by SMA basically consist of two or more diesel power sets, battery storage with converter, a rotating phaseshifter, and an optional number of wind turbines. All modules are coupled on the 3-phase AC system grid and run in various parallel configurations depending on the wind speed and the consumer power demand. The control system operates fully automatical and offers a very user-friendly graphical interface. This advanced system control also contains a remote control and operating data output via modem and telephone line. SMA and CES have considerable experience with Wind/Diesel/Battery Systems for more than eight years. In many cases wind energy converters in the power range of 30 to 40 kW were used, but it is also possible to use larger wind turbines (e.g. 250 kW). In the following the system technology is described in detail, experience of different system sizes in several countries of application is presented, and economical analyses for power supply by IPS are given in comparison to a conventional fully diesel power supply. (author)

  18. High-Performance, Reliable Solar Power for Smallsat Constellations

    Stern, Theodore; Walmsley, Nick


    Small satellites used in satellite constellations require high-performance, reliable solar power. Even with constellation redundancy, the risk to mission performance of solar panel failure is significant, and so extensive qualification and acceptance testing is normally implemented to assure reliability of customized solar panel designs To minimize these costs and risks, a modular, laminated solar panel design has been developed that combines highefficiency solar cells and space-qualified mat...

  19. 7 CFR 1710.303 - Power cost studies-power supply borrowers.


    ... this section. (Approved by the Office of Management and Budget under control number 0572-0032) ... AND GUARANTEES Long-Range Financial Forecasts § 1710.303 Power cost studies—power supply borrowers. (a... forecast required by § 1710.302. (b) A power cost study shall include the following basic elements: (1)...

  20. Digitally Controlled Envelope Tracking Power Supply for an RF Power Amplifier

    Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.


    due to clock frequency quantization. An envelope tracking power supply for an RF Power Amplifier (RFPA) can help improve system efficiency by reducing the power consumption of the RFPA. To show the advantage of the DiSOM over traditional counter based Digital PWM modulators two designs were compared...

  1. TEDS Base Station Power Amplifier using Low-Noise Envelope Tracking Power Supply

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael A. E.


    This paper demonstrates a highly linear and efficient TETRA enhanced data service (TEDS) base-station RF power amplifier (RFPA). Based on the well-known combination of an envelope tracking (ET) power supply and a linear class-A/B RFPA, adequate adjacent channel power ratio (ACPR) and wideband noise...

  2. Reliability/Cost Evaluation on Power System connected with Wind Power for the Reserve Estimation

    Lee, Go-Eun; Cha, Seung-Tae; Shin, Je-Seok;


    Wind power is ideally a renewable energy with no fuel cost, but has a risk to reduce reliability of the whole system because of uncertainty of the output. If the reserve of the system is increased, the reliability of the system may be improved. However, the cost would be increased. Therefore...... the reserve needs to be estimated considering the trade-off between reliability and economic aspects. This paper suggests a methodology to estimate the appropriate reserve, when wind power is connected to the power system. As a case study, when wind power is connected to power system of Korea, the effects...

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

    Ding, Yi; Østergaard, Jacob; Wu, Qiuwei


    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...... 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...... 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...

  4. Development of a PLC modem for data transmission over a PWM power supply

    Batard, Christophe; Ginot, Nicolas; Mannah, Marc Anthony; Millet, Christophe; Poitiers, Frédéric


    In variable-speed electrical drive and online conditioning monitoring, a feedback loop is required in order to transmit the sensor information from the motor to the controller close to the inverter. Additional cabling is used for signalling. This extra cabling has a significant cost and data transmission may not be reliable. Thus, the use of power line communication (PLC) technology to transmit data in motor drive application is quite interesting. The use of a PLC modem dedicated to the home network in a three-phase inverter-fed motor power cable does not work. Therefore, specific coupling interfaces are developed to transmit data through a pulse-width modulated power supply. Laboratory tests have shown that the couplers are operating properly. They ensure reliable data transmission in a motor drive application.

  5. Development of a photovoltaic power supply for wireless sensor networks.

    Harvey, Matthew R.; Kyker, Ronald D.


    This report examines the design process of a photovoltaic (solar) based power supply for wireless sensor networks. Such a system stores the energy produced by an array of photovoltaic cells in a secondary (rechargeable) battery that in turn provides power to the individual node of the sensor network. The goal of such a power supply is to enable a wireless sensor network to have an autonomous operation on the order of years. Ideally, such a system is as small as possible physically while transferring the maximum amount of available solar energy to the load (the node). Within this report, there is first an overview of current solar and battery technologies, including characteristics of different technologies and their impact on overall system design. Second is a general discussion of modeling, predicting, and analyzing the extended operation of a small photovoltaic power supply and setting design parameters. This is followed by results and conclusions from the testing of a few basic systems. Lastly, some advanced concepts that may be considered in order to optimize future systems will be discussed.

  6. Performance of current measurement system in poloidal field power supply for Experimental Advanced Superconducting Tokamak

    Liu, D. M.; Li, J.; Wan, B. N.; Lu, Z.; Wang, L. S.; Jiang, L.; Lu, C. H.; Huang, J.


    As one of the core subsystems of the Experimental Advanced Superconducting Tokamak (EAST), the poloidal field power system supplies energy to EAST's superconducting coils. To measure the converter current in the poloidal field power system, a current measurement system has been designed. The proposed measurement system is composed of a Rogowski coil and a newly designed integrator. The results of the resistor-inductor-capacitor discharge test and the converter equal current test show that the current measurement system provides good reliability and stability, and the maximum error of the proposed system is less than 1%.

  7. Performance Analyses of Renewable and Fuel Power Supply Systems for Different Base Station Sites

    Josip Lorincz


    Full Text Available Base station sites (BSSs powered with renewable energy sources have gained the attention of cellular operators during the last few years. This is because such “green” BSSs impose significant reductions in the operational expenditures (OPEX of telecom operators due to the possibility of on-site renewable energy harvesting. In this paper, the green BSSs power supply system parameters detected through remote and centralized real time sensing are presented. An implemented sensing system based on a wireless sensor network enables reliable collection and post-processing analyses of many parameters, such as: total charging/discharging current of power supply system, battery voltage and temperature, wind speed, etc. As an example, yearly sensing results for three different BSS configurations powered by solar and/or wind energy are discussed in terms of renewable energy supply (RES system performance. In the case of powering those BSS with standalone systems based on a fuel generator, the fuel consumption models expressing interdependence among the generator load and fuel consumption are proposed. This has allowed energy-efficiency comparison of the fuel powered and RES systems, which is presented in terms of the OPEX and carbon dioxide (CO2 reductions. Additionally, approaches based on different BSS air-conditioning systems and the on/off regulation of a daily fuel generator activity are proposed and validated in terms of energy and capital expenditure (CAPEX savings.

  8. FERMI magnet power supplies: design strategies and five years of operational experience

    Visintini, Roberto


    FERMI is the FEL-based light source in operation for external users since 2011 at the Elettra Research Center in Trieste, Italy. FERMI@Elettra is the name of the project for the construction and commissioning of this source. The design strategies adopted in the project had to consider the extremely close presence and the routine operation for users of the synchrotron-based source Elettra. There are more than 350 magnets and coils distributed along the linear accelerator, the two chains of undulators and the electron beam dump. Almost each magnetic element requires a dedicated DC power supply. Magnets, power supplies, and the connecting cables constitute a system, strongly interconnected with the remote control system, the machine and personnel safety system, and the infrastructure. All this has to fulfill the requirements from the particle physics specialists. We adopted a "systemic" approach in the design of new magnets and the re-use of the old ones, as well as the choice and the design of the associated power supplies. The commissioning of the systems started early 2010 and almost all magnet power supplies are in operation since then. During these 5 years, we introduced few minor upgrades and patches while the adopted solutions proved their soundness in terms of performance and reliability, causing very little downtime to the FERMI operations.

  9. 3 kA Power Supplies for the Duke OK-5 FEL Wigglers

    Popov, Victor; Mikhailov, Stepan; Oakeley, Owen; Wallace, Patrick W; Wu, Y K


    The next generation electromagnetic OK-5/Duke storage ring FEL wigglers require three 3kA/70V power supplies with current stability about 20 ppm and current ripples less than 20ppm in their full operating range. Duke FEL Laboratory acquired three out-of-service thyristor controllable power supplies (Transrex, 5kA/100V) which was built almost 30 years ago. The existing archaic firing circuit, lack of any output voltage filtering and outdated DCCT, would not be able to meet the above requirements.To deliver the desirable high performance with very limited funds, all three T-Rex power supplies have been completely rebuilt in house at DFELL. Modern high stability electronic components and a Danfysik DCCT with a high current stability have been used. New symmetrical firing circuit, efficient passive LC filter and reliable transformer-coupled active filter are used to reduce output current ripples to an appropriate level. At the present time, the first refurbished power supply in operation since August, 2004 with g...

  10. Incorporating Cyber Layer Failures in Composite Power System Reliability Evaluations

    Yuqi Han


    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.

  11. A battery-powered high-current power supply for superconductors

    Wake, M; Suda, K


    Since superconductors do not require voltages, a high-current power supply could run with low power if the voltage is sufficiently reduced. Even a battery-powered power supply could give as much as 2,000A for a superconductor. To demonstrate this hypothesis, a battery-powered 2,000A power supply was constructed. It uses an IGBT chopper and Schottky diode together with a specially arranged transformer to produce a high current with low voltage. Testing of 2,000A operation was performed for about 1.5 hr using 10 car batteries. Charging time for this operation was 8 hr. Ramping control was smooth and caused no trouble. Although the IGBT frequency ripple of 16.6 kHz was easily removed using a passive filter, spike noise remained in the output voltage. This ripple did not cause any trouble in operating a pancake-type inductive superconducting load. (author)

  12. Windfarm Generation Assessment for Reliability Analysis of Power Systems

    Barberis Negra, Nicola; Bak-Jensen, Birgitte; Holmstrøm, O.


    Due to the fast development of wind generation in the past ten years, increasing interest has been paid to techniques for assessing different aspects of power systems with a large amount of installed wind generation. One of these aspects concerns power system reliability. Windfarm modelling plays...... in a reliability model and the generation of a windfarm is evaluated by means of sequential Monte Carlo simulation. Results are used to analyse how each mentioned Factor influences the assessment, and why and when they should be included in the model....

  13. Windfarm Generation Assessment for ReliabilityAnalysis of Power Systems

    Negra, Nicola Barberis; Holmstrøm, Ole; Bak-Jensen, Birgitte


    Due to the fast development of wind generation in the past ten years, increasing interest has been paid to techniques for assessing different aspects of power systems with a large amount of installed wind generation. One of these aspects concerns power system reliability. Windfarm modelling plays...... in a reliability model and the generation of a windfarm is evaluated by means of sequential Monte Carlo simulation. Results are used to analyse how each mentioned Factor influences the assessment, and why and when they should be included in the model....

  14. Reliable and Power Efficient Routing Protocol for MANETs

    V.Sowmya Devi


    Full Text Available In this paper, we focused on of the most proliferated network that is Mobile Adhoc Network (MANET. Due to the dynamic nature and limited power of nodes, the routes will fail frequently which intern cause high power dissipation. This paper proposed a reliable and power efficient routing with the nodes having high power level. As well as, this approach also concentrated on the reduction of power consumption during route failures by adapting an on-demand local route recovery mechanism through a set of helping nodes and they are called as Support Nodes (SN. The cooperation of support nodes will reduce the power consumption and significantly increases the reliability. The performance of proposed approach was evaluated through average energy consumption, packet delivery ratio and end-to-end delay over varying node speed and varying packet size. The power optimization and reliability achieved by the proposed approach gives an ideal solution to the future communication in MANETs for a long time.

  15. Compact Reliable Robust (CORE) Power System for Auxiliary Power Applications


    SOFC stacks. The paper covers the power system development with the emphasis on the 300-hour demonstration of the 10 kWe reformer operating on JP-8...cell stack and its robustness while dramatically improving its tolerance to fuel impurities – closer to levels for SOFC stacks. This tolerance has...photograph of a SOFC reformer that was delivered to Army Research Laboratory (ARL). Presented in Figure 1b is a photograph of the 2 kWe reformer for HTPEM

  16. Advanced superconducting power cable for MV urban power supply

    Schmidt, Frank [Nexans Deutschland GmbH, Hannover (Germany); Merschel, Frank [RWE Deutschland AG, Essen (Germany); Noe, Mathias [Karlsruhe Institute of Technology, Karlsruhe (Germany)


    In recent years the technology of superconducting power cable systems has progressed such that the technical hurdles preparing for commercial applications have been mastered. Several field tests of large scale prototypes for the applications of superconducting cables as well as superconducting fault current limiters have been successfully accomplished and the technology of such systems is ready for commercialization. The presentation will give a detailed overview of the German AmpaCity project. An overview will be given on the development, manufacturing and installation of the 10 kV, 40 MVA HTS system consisting of a fault current limiter and of a 1 km cable in the city of Essen. Since it is the first time that a one kilometer HTS cable system is installed together with an HTS fault current limiter in a real grid application between two substations within a city center area, AmpaCity serves as a lighthouse project. In addition it is worldwide the longest installed HTS cable system so far. It is expected that relatively large technical advances will be made in the future of the comparatively new HTS technology, which in turn will bring associated cost reductions. For this reason, the AmpaCity pilot project in the downtown area of Essen in Germany will be an important step on the way to achieving more widespread application of HTS technology.

  17. 250 kV 6 mA compact Cockcroft-Walton high-voltage power supply.

    Ma, Zhan-Wen; Su, Xiao-Dong; Lu, Xiao-Long; Wei, Zhen; Wang, Jun-Run; Huang, Zhi-Wu; Miao, Tian-You; Su, Tong-Ling; Yao, Ze-En


    A compact power supply system for a compact neutron generator has been developed. A 4-stage symmetrical Cockcroft-Walton circuit is adopted to produce 250 kV direct current high-voltage. A 2-stage 280 kV isolation transformer system is used to drive the ion source power supply. For a compact structure, safety, and reliability during the operation, the Cockcroft-Walton circuit and the isolation transformer system are enclosed in an epoxy vessel containing the transformer oil whose size is about ∅350 mm × 766 mm. Test results indicate that the maximum output voltage of the power supply is 282 kV, and the stability of the output voltage is better than 0.63% when the high voltage power supply is operated at 250 kV, 6.9 mA with the input voltage varying ±10%.

  18. 250 kV 6 mA compact Cockcroft-Walton high-voltage power supply

    Ma, Zhan-Wen; Su, Xiao-Dong; Lu, Xiao-Long; Wei, Zhen; Wang, Jun-Run; Huang, Zhi-Wu; Miao, Tian-You; Su, Tong-Ling; Yao, Ze-En


    A compact power supply system for a compact neutron generator has been developed. A 4-stage symmetrical Cockcroft-Walton circuit is adopted to produce 250 kV direct current high-voltage. A 2-stage 280 kV isolation transformer system is used to drive the ion source power supply. For a compact structure, safety, and reliability during the operation, the Cockcroft-Walton circuit and the isolation transformer system are enclosed in an epoxy vessel containing the transformer oil whose size is about ∅350 mm × 766 mm. Test results indicate that the maximum output voltage of the power supply is 282 kV, and the stability of the output voltage is better than 0.63% when the high voltage power supply is operated at 250 kV, 6.9 mA with the input voltage varying ±10%.

  19. Evaluation of nodal reliability risk in a deregulated power system with photovoltaic power penetration

    Zhao, Qian; Wang, Peng; Goel, Lalit


    and customer reliability requirements are correlated with energy and reserve prices. Therefore a new method should be developed to evaluate the impacts of PV power on customer reliability and system reserve deployment in the new environment. In this study, a method based on the pseudo-sequential Monte Carlo......Owing to the intermittent characteristic of solar radiation, power system reliability may be affected with high photovoltaic (PV) power penetration. To reduce large variation of PV power, additional system balancing reserve would be needed. In deregulated power systems, deployment of reserves...... simulation technique has been proposed to evaluate the reserve deployment and customers' nodal reliability with high PV power penetration. The proposed method can effectively model the chronological aspects and stochastic characteristics of PV power and system operation with high computation efficiency...

  20. Testing of Uninterruptible Power Supplies with nonlinear loads

    Heydt, Gerald; Briggs, Steve; Holcomb, Franklin; Edgar, Daiva


    Uninterruptible power supplies (UPS's) are used to provide power to sensitive and critical loads when the commercial supply has been interrupted. These loads may be nonlinear, which in the military often includes communications equipment, adjustable speed drives, fluorescent lighting, and mainframe and small computers. Most electrical characteristics of UPS's are not currently subject to codes and standards, and there are no military specifications for UPS's. Existing standards assume that UPS's will be operated with linear loads. Since most UPS systems are operated with nonlinear loads, there is concern that UPSs will suffer degraded performance or failure when operated with these loads. This work developed a test methodology by which UPS systems can be tested and their susceptibility to nonlinear loads quantified. The tests measure load transfer, efficiency, heating, load support, voltage regulation, and isolation. Several commercially available UPS systems are recommended for testing.

  1. Reliability Evaluation of a Distribution Network with Microgrid Based on a Combined Power Generation System

    Hao Bai


    Full Text Available Distributed generation (DG, battery storage (BS and electric vehicles (EVs in a microgrid constitute the combined power generation system (CPGS. A CPGS can be applied to achieve a reliable evaluation of a distribution network with microgrids. To model charging load and discharging capacity, respectively, the EVs in a CPGS can be divided into regular EVs and ruleless EVs, according to their driving behavior. Based on statistical data of gasoline-fueled vehicles and the probability distribution of charging start instant and charging time, a statistical model can be built to describe the charging load and discharging capacity of ruleless EVs. The charge and discharge curves of regular EVs can also be drawn on the basis of a daily dispatch table. The CPGS takes the charge and discharge curves of EVs, daily load and DG power generation into consideration to calculate its power supply time during islanding. Combined with fault duration, the power supply time during islanding will be used to analyze and determine the interruption times and interruption duration of loads in islands. Then the Sequential Monte Carlo method is applied to complete the reliability evaluation of the distribution system. The RBTS Bus 4 test system is utilized to illustrate the proposed technique. The effects on the system reliability of BS capacity and V2G technology, driving behavior, recharging mode and penetration of EVs are all investigated.

  2. Modern Solutions for Automation of Electrical Traction Power Supply Systems

    Ana Mihaela Andreica


    Full Text Available This paper presents modern solutions for the automation of the electrical traction power supply system used in urban public transport (trams, trolleybuses and subway trains. The monitoring and control of this process uses SCADA distributed architectures, grouped around a central point (dispatcher who controls all field sensors, transmitters and actuators using programmable logical controllers. The presented applications refer to the Bucharest electrical transport infrastructure.

  3. Systems for uninterrupted power supply; USV - ein starkes Stueck Sicherheit

    Schneider, D.; Soelter, W. [AEG SVS GmbH, Warstein-Belecke (Germany)


    The millennium bug is only one of the many potential hazards in information technology. Systems for uninterrupted power supply offer a solution. [German] Alle Welt spricht vom Jahr-2000-Problem (Y2K). Die Meinungen dazu reichen von Horror-Szenarien bis hin zum Ignorieren dieses Problems. Dabei steht fest: Das Jahr-2000-Problem ist nur eines unter vielen Gefahrenpotentialen fuer die Informationstechnik. Dabei lassen sich alle Stoerfaktoren, die aus der Energieversorgung resultieren mit einer USV beseitigen. USV sichern Geschaeftsablaeufe und Fertigungsprozesse. (orig.)

  4. 兼顾供电可靠性和 LCC 的变电站主设备检修策略优化方法%Maintenance Strategy Optimization for Main Equipment in Substations Considering Both Power Supply Reliability and Life Cycle Cost

    郭丽娟; 陶松梅; 张炜


    提出了一种能够同时兼顾变电站供电可靠性和设备全寿命周期成本(LCC)的设备检修决策优化方法。该方法选择变电站中的待检变压器和断路器,利用健康指数(HI)和役龄回退因子分别计算待检设备检修前后的故障率;通过变电站的预想事故分析和负荷削减状态的枚举,计算设备检修前后变电站电量不足期望(EENS)和设备 LCC 的变化量;最后,分别给出以可靠性优先、经济性优先和费效比优先作为评价指标的优化检修策略。某220 kV 变电站的检修决策实例表明,该方法能够综合考虑变电站的供电可靠性和设备的 LCC ,制定合理有效的检修策略。在有效降低变电站供电风险的前提下提高设备检修效率,减小检修维护成本。%A new optimization method for maintenance decision‐making considering both power supply reliability of the substation and the life cycle cost ( LCC ) of equipment is proposed . According to the Transmission Equipment Risk Assessment Guidelines" made by Southern Power Grid Company , transformers or circuit breakers to be maintained are chosen . Then the failure rate of equipment before and after maintenance is calculated based on the health index ( HI) and the age reduction factor , respectively . Further , the variable quantity of the substation expected energy not served ( EENS) and the LCC of equipment before and after maintenance can be quantified by applying the contingency analysis and the load reduction state enumeration , respectively . Finally , an optimized maintenance strategy is given according to three different assessment criteria , including the priority to reliability , economy and cost‐effectiveness ratio . An application example in a 220 kV substation shows the method is able to improve maintenance efficiency and reduce cost with the risks to the substation effectively reduced .

  5. A Multi-channel AC Power Supply Controller


    A multi-channel AC power Supply controler developed recently by us was introdueed briefty in this paper.This controller is a computer controlled multi-electronic-switch device.The controller contains 16 independent channels in a standard box(440W×405D×125H mm).There is an electronic switch in each channel,the rated load power is≤1 kW.The main function of the controller is to set the state of electronic switch(ON/OFF)

  6. Development of compact rapid charging power supply for capacitive energy storage in pulsed power drivers

    Sharma, Surender Kumar; Shyam, Anurag


    High energy capacitor bank is used for primary electrical energy storage in pulsed power drivers. The capacitors used in these pulsed power drivers have low inductance, low internal resistance, and less dc life, so it has to be charged rapidly and immediately discharged into the load. A series resonant converter based 45 kV compact power supply is designed and developed for rapid charging of the capacitor bank with constant charging current up to 150 mA. It is short circuit proof, and zero current switching technique is used to commute the semiconductor switch. A high frequency resonant inverter switching at 10 kHz makes the overall size small and reduces the switching losses. The output current of the power supply is limited by constant on-time and variable frequency switching control technique. The power supply is tested by charging the 45 kV/1.67 μF and 15 kV/356 μF capacitor banks. It has charged the capacitor bank up to rated voltage with maximum charging current of 150 mA and the average charging rate of 3.4 kJ/s. The output current of the power supply is limited by reducing the switching frequency at 5 kHz, 3.3 kHz, and 1.7 kHz and tested with 45 kV/1.67 μF capacitor bank. The protection circuit is included in the power supply for over current, under voltage, and over temperature. The design details and the experimental testing results of the power supply for resonant current, output current, and voltage traces of the power supply with capacitive, resistive, and short circuited load are presented and discussed.

  7. Controlling chaos in a satellite power supply subsystem

    Macau, E. E. N.; Ramos Turci, L. F.; Yoneyama, T.


    In this work, we show that chaos control techniques can be used to increase the region that can be efficiently used to supply the power requests for an artificial satellite. The core of a satellite power subsystem relies on its DC/DC converter. This is a very nonlinear system that presents a multitude of phenomena ranging from bifurcations, quasi-periodicity, chaos, coexistence of attractors, among others. The traditional power subsystem design techniques try to avoid these nonlinear phenomena so that it is possible to use linear system theory in small regions about the equilibrium points. Here, we show that chaos control can be used to efficiently extend the applicability region of the satellite power subsystem when it operates in regions of high nonlinearity.

  8. 275 C Downhole Switched-Mode Power Supply

    Chris Hutchens; Vijay Madhuravasal


    A vee-square (V2) control based controller IC is developed for a switch mode power supply capable of operating at extreme temperature/harsh environment conditions. A buck type regulator with silicon carbide power junction field effect transistors (JFET) as power devices is used to analyze the performance of controller. Special emphases are made on the analog sub-blocks--voltage reference, operational transconductance amplifier and comparator as individual building blocks. Transformer coupled gate drives and high temperature operable magnetic cores and capacitors are identified and tested for use in the design. Conventional ceramic chip packaging of ICs combined with lead carrier type mounting of passive filter components is introduced for hybrid packaging of the complete product. The developed SMPS is anticipated to support the operation of down-hole microcontrollers and other electronics devices that require low/medium power filtered dc inputs over an operating temperature of 275 C.

  9. Fuse Modeling for Reliability Study of Power Electronics Circuits

    Bahman, Amir Sajjad; Iannuzzo, Francesco; Blaabjerg, Frede


    This paper describes a comprehensive modeling approach on reliability of fuses used in power electronic circuits. When fuses are subjected to current pulses, cyclic temperature stress is introduced to the fuse element and will wear out the component. Furthermore, the fuse may be used in a large...

  10. Fuse Modeling for Reliability Study of Power Electronics Circuits

    Bahman, Amir Sajjad; Iannuzzo, Francesco; Blaabjerg, Frede


    This paper describes a comprehensive modeling approach on reliability of fuses used in power electronic circuits. When fuses are subjected to current pulses, cyclic temperature stress is introduced to the fuse element and will wear out the component. Furthermore, the fuse may be used in a large...

  11. Comparison of maintenance scheme effects on power transformer reliability performance

    I. C. Durán


    Full Text Available Power transformer failures have a significant impact on electrical systems reliability, as they compromise the electricity delivery. Failures impact the operational cost of electric utilities as they endanger the accomplishment of power commitments. Power transformer failure rate can be modeled from its health condition, which is determined from different condition parameters. This paper is aimed to compare different maintenance schemes that allow the asset to be available the longest possible time. The power transformer operation is represented considering actual electric load profiles and temperature. Electrical and thermal transformer parameters are taken from manufacturer tests and technical standards. An electrical-thermal model is employed to estimate the life span reduction and temperature changes. From life span and loading, the health condition is determined, so as the effects of different maintenance schemes. The failure rates are calculated for unmaintained conditions and different maintained schemes, allowing to determine their effects on transformer reliability. Optimal maintenance schemes are determined and the expected benefits in failure rate reduction, asset reliability and life span extension are presented. As a result, it was found that certain time-based maintenance schemes provide better transformer reliability performance in comparison to condition based schemes, allowing to reduce the interruptions and extending the life of the transformer.

  12. Design of an AC/DC power supply for telecom applications

    Suntio, T.; Vallittu, P.; Laurinen, T.; Ikonen, M. [Efore Oy, Espoo (Finland)


    Typical Telecom uninterruptible power supply system (UPS) comprises of parallel connected rectifiers and storage batteries supplying DC power for Telecom switching systems on fixed or mobile telephone networks. The requirement is most often of total uninterruptibility meaning high reliability and availability performance as a vital design and development goal. The Telecom systems must also meet stringent noise emission and immunity requirements stipulated by EMC and Low Voltage Directives, European Telecommunications Standard Institute (ETSI) as well as other global and local standards depending on the area they are to be used. This paper will describe in practice the vital features the rectifiers should contain as well as presents results from a practical equipment of 48 V, 500 W. (orig.) 27 refs.

  13. Layouts of trigeneration plants for centralized power supply

    Klimenko, A. V.; Agababov, V. S.; Il'ina, I. P.; Rozhnatovskii, V. D.; Burmakina, A. V.


    One of the possible and, under certain conditions, sufficiently effective methods for reducing consumption of fuel and energy resources is the development of plants for combined generation of different kinds of energy. In the power industry of Russia, the facilities have become widespread in which the cogeneration technology, i.e., simultaneous generation of electric energy and heat, is implemented. Such facilities can use different plants, viz., gas- and steam-turbine plants and gas-reciprocating units. Cogeneration power supply can be further developed by simultaneously supplying the users not only with electricity and heat but also with cold. Such a technology is referred to as trigeneration. To produce electricity and heat, trigeneration plants can use the same facilities that are used in cogeneration, namely, gas-turbine plants, steam-turbine plants, and gas-reciprocating units. Cold can be produced in trigeneration plants using thermotransformers of various kinds, such as vaporcompression thermotransformers, air thermotransformers, and absorption thermotransformers, that operate as chilling machines. The thermotransformers can also be used in the trigeneration plants to generate heat. The main advantage of trigeneration plants based on gas-turbine plants or gas-reciprocating units over cogeneration plants is the increased thermodynamic power supply efficiency owing to utilization of the waste-gas heat not only in winter but also in summer. In the steam-turbine-based trigeneration plants equipped with absorption thermotransformers, the enhancement of the thermodynamic power supply efficiency is determined by the increase in the heat extraction load during the nonheating season. The article presents calculated results that demonstrate higher thermodynamic efficiency of a gas-turbine-based plant with an absorption thermotransformer that operates in the trigeneration mode compared with a cogeneration gas-turbine plant. The structural arrangements of trigeneration

  14. A multi-objective reliable programming model for disruption in supply chain

    Emran Mohammadi


    Full Text Available One of the primary concerns on supply chain management is to handle risk components, properly. There are various reasons for having risk in supply chain such as natural disasters, unexpected incidents, etc. When a series of facilities are built and deployed, one or a number of them could probably fail at any time due to bad weather conditions, labor strikes, economic crises, sabotage or terrorist attacks and changes in ownership of the system. The objective of risk management is to reduce the effects of different domains to an acceptable level. To overcome the risk, we propose a reliable capacitated supply chain network design (RSCND model by considering random disruptions risk in both distribution centers and suppliers. The proposed study of this paper considers three objective functions and the implementation is verified using some instance.

  15. The impact of forest thinning on the reliability of water supply in central Arizona.

    Silvio Simonit

    Full Text Available Economic growth in Central Arizona, as in other semiarid systems characterized by low and variable rainfall, has historically depended on the effectiveness of strategies to manage water supply risks. Traditionally, the management of supply risks includes three elements: hard infrastructures, landscape management within the watershed, and a supporting set of institutions of which water markets are frequently the most important. In this paper we model the interactions between these elements. A forest restoration initiative in Central Arizona (the Four Forest Restoration Initiative, or 4FRI will result in thinning of ponderosa pine forests in the upper watershed, with potential implications for both sedimentation rates and water delivery to reservoirs. Specifically, we model the net effect of ponderosa pine forest thinning across the Salt and Verde River watersheds on the reliability and cost of water supply to the Phoenix metropolitan area. We conclude that the sediment impacts of forest thinning (up to 50% of canopy cover are unlikely to compromise the reliability of the reservoir system while thinning has the potential to increase annual water supply by 8%. This represents an estimated net present value of surface water storage of $104 million, considering both water consumption and hydropower generation.

  16. Design of power supply system for LWD%随钻电源系统设计

    仇傲; 李源; 刘西恩; 肖兵


    Multiple power system which can be reliable switch is needed to use in logging while drilling(LWD) equipment by the influence of structure and working environment.A power supply system for LWD equipment is designed.The system can switchover power supply according to different source,meanwhile supplies several second power for load.The second power is converted by BUCK DC-DC converters.Simulation and test results show that the system has advantages of reliable,low power consumption and high stability,meet the practical demand of LWD.%随钻仪器受到自身结构和工作环境影响,因此需要使用多路电源系统供电并可以可靠自动切换。由于供电主体为电池,该电源系统还需要具有较高的转换效率以提高仪器工作时间。本文设计了一种随钻电源系统。该系统可完成随钻仪器在不同供电来源间根据设计进行自动切换。并且提供井下仪器需求的各路次级电源。二次电源转换部分采用BUCK型开关电源设计,在保证转换效率的基础上减小输出纹波。仿真和测试结果表明该系统能可靠切换且功耗低,稳定性好,满足随钻测井仪器需求。

  17. Human reliability, error, and human factors in power generation

    Dhillon, B S


    Human reliability, error, and human factors in the area of power generation have been receiving increasing attention in recent years. Each year billions of dollars are spent in the area of power generation to design, construct/manufacture, operate, and maintain various types of power systems around the globe, and such systems often fail due to human error. This book compiles various recent results and data into one volume, and eliminates the need to consult many diverse sources to obtain vital information.  It enables potential readers to delve deeper into a specific area, providing the source of most of the material presented in references at the end of each chapter. Examples along with solutions are also provided at appropriate places, and there are numerous problems for testing the reader’s comprehension.  Chapters cover a broad range of topics, including general methods for performing human reliability and error analysis in power plants, specific human reliability analysis methods for nuclear power pl...

  18. Station power supply by residual steam of Fugen

    Kamiya, Y.; Kato, H.; Hattori, S. (Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan))


    In the advanced thermal reactor ''Fugen'', when the sudden decrease of load more than 40% occurs due to the failure of power system, the turbine regulating valve is rapidly shut, and the reactor is brought to scrum. However, the operation of turbo-generators is continued with the residual steam in the reactor, and the power for inside the station is supplied for 30 sec by the limiting timer, then the power-generating plant is automatically stopped. The reasons why such design was adopted are to reduce manual operation at the time of emergency, to continue water supply for cooling the reactor and to maintain the water level in the steam drum, and to reduce steam release from the safety valve and the turbine bypass valve. The output-load unbalance relay prevents the everspeed of the turbo-generator when load decreased suddenly, but when the failure of power system is such that recovers automatically in course of time, it does not work. The calculation for estimating the dynamic characteristics at the time of the sole operation within the station is carried out by the analysis code FATRAC. The input conditions for the calculation and the results are reported. Also the dynamic characteristics were actually tested to confirm the set value of the limiting timer and the safe working of turbine and generator trips. The estimated and tested results were almost in agreement.

  19. Magnet power supply regulation comments: 240 kW and 500 kW magnet power supplies

    Visser, A.T.


    This note is written for users who need better than about 100 ppm regulated magnet fields in electromagnets. A magnet excitation current regulation of 100 ppm is generally specified to obtain this field regulation, but there are many other variables, in addition to magnet excitation that can change the magnet field. The effects of these other variables are often overlooked or underestimated. If things do not work out, the power supply often gets blamed. A field regulation of 100 ppm requires that the power supply regulates substantially better than 100 ppm and that the effects of other variables are limited. Before we can talk about regulation we must define what regulation is. Power supplies can be regulated for current or voltage. We will only talk about current regulation, since that is the regulation mode used to establish precisely regulated magnetic fields in electromagnets. It is assumed that the same current value will always produce the same corresponding magnetic field value. Later on we will discuss that this assumption is not correct.

  20. Reliability and discriminatory power of methods for dental plaque quantification

    Daniela Prócida Raggio


    Full Text Available OBJECTIVE: This in situ study evaluated the discriminatory power and reliability of methods of dental plaque quantification and the relationship between visual indices (VI and fluorescence camera (FC to detect plaque. MATERIAL AND METHODS: Six volunteers used palatal appliances with six bovine enamel blocks presenting different stages of plaque accumulation. The presence of plaque with and without disclosing was assessed using VI. Images were obtained with FC and digital camera in both conditions. The area covered by plaque was assessed. Examinations were done by two independent examiners. Data were analyzed by Kruskal-Wallis and Kappa tests to compare different conditions of samples and to assess the inter-examiner reproducibility. RESULTS: Some methods presented adequate reproducibility. The Turesky index and the assessment of area covered by disclosed plaque in the FC images presented the highest discriminatory powers. CONCLUSION: The Turesky index and images with FC with disclosing present good reliability and discriminatory power in quantifying dental plaque.

  1. Integrated approach to economical, reliable, safe nuclear power production


    An Integrated Approach to Economical, Reliable, Safe Nuclear Power Production is the latest evolution of a concept which originated with the Defense-in-Depth philosophy of the nuclear industry. As Defense-in-Depth provided a framework for viewing physical barriers and equipment redundancy, the Integrated Approach gives a framework for viewing nuclear power production in terms of functions and institutions. In the Integrated Approach, four plant Goals are defined (Normal Operation, Core and Plant Protection, Containment Integrity and Emergency Preparedness) with the attendant Functional and Institutional Classifications that support them. The Integrated Approach provides a systematic perspective that combines the economic objective of reliable power production with the safety objective of consistent, controlled plant operation.

  2. Analyzing Power Supply and Demand on the ISS

    Thomas, Justin; Pham, Tho; Halyard, Raymond; Conwell, Steve


    Station Power and Energy Evaluation Determiner (SPEED) is a Java application program for analyzing the supply and demand aspects of the electrical power system of the International Space Station (ISS). SPEED can be executed on any computer that supports version 1.4 or a subsequent version of the Java Runtime Environment. SPEED includes an analysis module, denoted the Simplified Battery Solar Array Model, which is a simplified engineering model of the ISS primary power system. This simplified model makes it possible to perform analyses quickly. SPEED also includes a user-friendly graphical-interface module, an input file system, a parameter-configuration module, an analysis-configuration-management subsystem, and an output subsystem. SPEED responds to input information on trajectory, shadowing, attitude, and pointing in either a state-of-charge mode or a power-availability mode. In the state-of-charge mode, SPEED calculates battery state-of-charge profiles, given a time-varying power-load profile. In the power-availability mode, SPEED determines the time-varying total available solar array and/or battery power output, given a minimum allowable battery state of charge.

  3. Optimized Envelope Tracking Power Supply for Tetra2 Base Station RF Power Amplifier

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.


    An ultra-fast tracking power supply (UFTPS) for envelope tracking in a 50kHz 64-QAM Tetra2 base station power amplification system is demonstrated. A simple method for optimizing the step response of the PID+PD sliding-mode control system is presented and demonstrated, along with a PLL-based scheme...




    Full Text Available Reducing the number of switches andpassive elements in uninterruptible power supplytopologies not only reduces the cost of the wholesystem but also provides some other advantagessuch as greater compactness, smaller weight, andhigher reliability. Generally, the largest costreduction is achieved by reducing the number ofswitches employed in a converter power circuit.Another way of reducing the cost of converters is touse a topology that allows replacing activeswitches, such as IGBTs, MOSFETs, andthyristors, with diodes. Diodes are less expensivethan active switches and apart from this, there isalso a cost reduction from eliminating all thecircuitry for driving active switches.

  5. Reliability methods in nuclear power plant ageing management

    Simola, K. [VTT Automation, Espoo (Finland). Industrial Automation


    The aim of nuclear power plant ageing management is to maintain an adequate safety level throughout the lifetime of the plant. In ageing studies, the reliability of components, systems and structures is evaluated taking into account the possible time-dependent degradation. The phases of ageing analyses are generally the identification of critical components, identification and evaluation of ageing effects, and development of mitigation methods. This thesis focuses on the use of reliability methods and analyses of plant- specific operating experience in nuclear power plant ageing studies. The presented applications and method development have been related to nuclear power plants, but many of the approaches can also be applied outside the nuclear industry. The thesis consists of a summary and seven publications. The summary provides an overview of ageing management and discusses the role of reliability methods in ageing analyses. In the publications, practical applications and method development are described in more detail. The application areas at component and system level are motor-operated valves and protection automation systems, for which experience-based ageing analyses have been demonstrated. Furthermore, Bayesian ageing models for repairable components have been developed, and the management of ageing by improving maintenance practices is discussed. Recommendations for improvement of plant information management in order to facilitate ageing analyses are also given. The evaluation and mitigation of ageing effects on structural components is addressed by promoting the use of probabilistic modelling of crack growth, and developing models for evaluation of the reliability of inspection results. (orig.)

  6. Power system reliability impacts of wind generation and operational reserve requirements

    E. Gil


    Full Text Available Due to its variability, wind generation integration presents a significant challenge to power system operators in order to maintain adequate reliability levels while ensuring least cost operation. This paper explores the trade-off between the benefits associated to a higher wind penetration and the additional operational reserve requirements that they impose. Such exploration is valued in terms of its effect on power system reliability, measured as an amount of unserved energy. The paper also focuses on how changing the Value of Lost Load (VoLL can be used to attain different reliability targets, and how wind power penetration and the diversity of the wind energy resource will impact quality of supply (in terms of instances of unserved energy. The evaluation of different penetrations of wind power generation, different wind speed profiles, wind resource diversity, and different operational reserve requirements, is conducted on the Chilean Northern Interconnected System (SING using statistical modeling of wind speed time series and computer simulation through a 24-hour ahead unit commitment algorithm and a Monte Carlo simulation scheme. Results for the SING suggest that while wind generation can significantly reduce generation costs, it can also imply higher security costs to reach acceptable reliability levels.

  7. 76 FR 7187 - Priorities for Addressing Risks to the Reliability of the Bulk-Power System; Reliability...


    ... Energy Regulatory Commission Priorities for Addressing Risks to the Reliability of the Bulk- Power System; Reliability Technical Conference Panel February 2, 2011. As announced in the Notice of Technical Conference..., to discuss policy issues related to reliability of the Bulk-Power System, including priorities...

  8. Reliability-cost models for the power switching devices of wind power converters

    Ma, Ke; Blaabjerg, Frede


    In order to satisfy the growing reliability requirements for the wind power converters with more cost-effective solution, the target of this paper is to establish a new reliability-cost model which can connect the relationship between reliability performances and corresponding semiconductor cost...... for power switching devices. First the conduction loss, switching loss as well as thermal impedance models of power switching devices (IGBT module) are related to the semiconductor chip number information respectively. Afterwards simplified analytical solutions, which can directly extract the junction...

  9. The Power Supply System for the J-TEXT Poloidal Field

    ZHANG Ming; ZHUANG Ge; YU Kexun; QiU Shengshun; PAN Yuan


    Joint-TEXT(J-TEXT)is a medium-sized tokamak constructed at Huazhong University of Science and Technology.At present,the poloidal field power supply consists of three subsystem sets,namely Ohmic heating field power supply,vertical field power supply,and horizontal field power supply.The structure and function of the poloidal field(PF)power supply aus well as the updated control system of the power supply is described.The new scheme uses the realtime feedback control method for the poloidal field power supply.The experimental results show that the poloidal field energized by poloidal field power supply meets the J-TEXT operational requirement perfectly.

  10. Reliability of power output during eccentric sprint cycling.

    Brughelli, Matt; Van Leemputte, Marc


    The purpose of this study was to determine the reliability of power outputs during maximal intensity eccentric cycling over short durations (i.e., eccentric sprint cycling) on a "motor-driven" isokinetic ergometer. Fourteen physically active male subjects performed isokinetic eccentric cycling sprints at 40, 60, 80, 100, and 120 revolutions per minute (rpm) on 4 separate occasions (T1-T4). Each sprint lasted for 6 seconds, and absolute measures of mean power (MP) and peak power (PP) per revolution were recorded. Significant increases in MP and PP were observed between T1 and subsequent trials, but no significant differences were identified between T2, T3, and T4. The coefficient of variation (CV) and intraclass correlation coefficient (ICC) were calculated to reflect within-subject and between-session reliability of MP and PP at each cadence. The CV improved to below 10% for cadences of 60, 80, 100, and 120 rpm between T3 and T4, and the majority of ICC values improved to above 0.90. The remaining ICC values remained in the moderate range between T3 and T4 (i.e., 0.82-0.89). Coefficient of variation and ICC values for the 40 rpm cadence remained at unacceptable levels throughout the 4 trials and thus should be avoided in future investigations. The results of this study indicate that reliable power outputs may be obtained after 2 familiarization sessions during eccentric sprint cycling at cadences ranging from 60 to 120 rpm.

  11. Powering Up” for the 21st Century: The Power Supply Industry in Major Transition



    The power supply industry is changing more today than ever before. From business composition to architectures, design methods, sourcing, geographic composition and infrastructure, every element of the power supply industry is changing. The challenges are dramatic, with solutions having long term impact. An overview is presented of the power supply industry today based on the author's industry association work, experience as a supplier, and discussions with industry leaders. Since power supplies is such a broad subject, the paper's focus is on some key aspects of the industry that may have wide interest to readers and participants. The major trends, market drivers, and issues are examined with some basic conclusions and challenges cited. The objective is to provide the reader with 1) a better overall impression of the state of the power supply industry is today 2) some insight into what the transitional driving elements are and 3) some ideas for assisting in the transitioning movements. The comments are mainly regarding North America and Europe, however these trends are affecting the Asian and Japanese regions.

  12. Composite Energy Storage System with Photovoltaic Power Generation and Uninterruptible Power Supply Function

    Jung-Min Kwon


    A composite energy storage system (CESS) that includes a photovoltaic (PV) power generation and an uninterruptible power supply (UPS) function is proposed. This system has three operating modes, namely, a grid-connected inverter mode, a grid-connected rectifier mode, and an islanding mode. This system is composed of a boost converter, a three-phase inverter/rectifier, a bidirectional DC/DC converter, and thyristor switches. The boost converter extracts maximum power from the PV panels and sen...

  13. Reliability Assessment Considering the Coordination of Wind Power, Solar Energy and Energy Storage

    WANG Haiying; BAI Xiaomin; XU Jing


    Large-scale integration of wind power and solar photovoltaic (PV) power in an electric grid can result in a high operating risk due to their randomness and intermi- ttency. Energy storage (ES) can be used to coordinate with them to reduce this risk by improving supply continuity. It is therefore important to evaluate the reliability benefits of systems consist of wind power, solar photovoltaic power and energy storage. The objective of this paper is to evaluate how the parameters such as the capacity and characteristics of ES and the configuration of a hybrid generation system (HGS) affect the system adequacy based on the sequential Monte Carlo approach.

  14. Power shifts in the Australian agrifood supply chain

    McKinna, David


    Over the past two years, the oligopsony of Australia’s big two supermarkets has been put under the spotlight. Woolworths was the dominant retailer, powering ahead of Coles which was lost in the haze of a dysfunctional management team and a poor business model. With the arrival of Coles’ new team from the UK, the sleeping tiger has leapt into battle to recover years of lost time. The Coles recovery strategy and Woolworths defensive response has thrown agrifood supply chains into disarray. Milk...

  15. Klystron switching power supplies for the Internation Linear Collider

    Fraioli, Andrea; /Cassino U. /INFN, Pisa


    The International Linear Collider is a majestic High Energy Physics particle accelerator that will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. ILC will complement the Large Hadron Collider (LHC), a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, by producing electron-positron collisions at center of mass energy of about 500 GeV. In particular, the subject of this dissertation is the R&D for a solid state Marx Modulator and relative switching power supply for the International Linear Collider Main LINAC Radio Frequency stations.

  16. Ablation response testing of simulated radioisotope power supplies

    Lutz, Steven A.; Chan, Chris C.


    Results of an experimental program to assess the aerothermal ablation response of simulated radioisotope power supplies are presented. Full-scale general purpose heat source, graphite impact shell, and lightweight radioisotope heater unit test articles are all tested without nuclear fuel in simulated reentry environments. Convective stagnation heating, stagnation pressure, stagnation surface temperature, surface recession profile, and weight loss measurements are obtained for diffusion-limited and sublimation ablation conditions. The recession profile and weight loss measurements show an effect of surface features on the stagnation face. The surface features alter the local heating which in turn affects the local ablation.

  17. Development of insulated gate bipolar transistor-based power supply for elemental copper vapour laser

    R K Mishra; S V Nakhe; G N Tiwari; J K Mittal


    The elemental copper vapour laser is a widely used laser from a family of metal vapour lasers for applications such as dye laser pumping, micromachining etc. In this paper, we report the development and performance of IGBT-based pulsed power supply that replaced conventional thyratron-based power supply for 4.7 cm diameter, 150 cm long copper vapour laser. The laser tube delivered an average power of 51 W, which with conventional power supply was giving 40 W. The IGBT-based power supply offers considerable reduction in the running cost of the laser. It is more user-friendly when compared with the conventional power supply.

  18. DC uninterrupted power supply having instantaneous switching followed by low impedance switching

    Hammond, Russell E.; Northup, Robert L.; Shimp, Alan G.


    An uninterruptible power supply is provided that incorporates switching circuitry permitting a path for instantaneous DC backup power to be supplied to a voltage-declining primary power supply bus. Once the instantaneous transition is made, battery power is switched to a low impedance path to provide long-term battery power delivery to the bus. At a point where the backup batteries no longer supply useful power to a load, disabling circuitry disconnects the batteries from the load so that excessive draining of the batteries does not result in irreversible battery damage. The uninterruptible power supply of the invention further includes an automatic battery charging circuitry that seeks to maintain the power supply batteries at optimal charge level. To enable an operator to adequately assess battery charge condition, the invention provides battery test circuitry that causes a simulated load to appear at the power supply batteries. Visual representations are then made as to battery status.

  19. AC Power Routing System in Home Based on Demand and Supply Utilizing Distributed Power Sources

    Takashi Hikihara


    Full Text Available To help reduce consumption of fossil fuels, renewable, natural and distributed power sources are being adopted. These alternative energy sources inevitably show fluctuations in the amount of output power, frequency, and voltage. The suppression of such fluctuations is a key issue to avoid disturbances in power grids. A similar situation arises as far as the regulation of in-home power flow is concerned. We focus on the quality of supplied and demanded power in particular. In this paper, an in-home power distribution system based on information of power is proposed. The system is developed in order to integrate power dispatch and communication. The experimental results show the feasibility of new flexible and efficient power management approaches.

  20. System design of the traction power supply for the high-speed line Beijing - Tianjin

    Altmann, Martin; Fischer, Andreas; Tornow, Torsten [Siemens AG, Erlangen (Germany)


    The high-speed line Beijing - Tianjin connecting the Capital Beijing with the harbour city Tianjin is the first high-speed line in China dedicated only to passenger traffic and is operated at 300 km/h. The commercial service started in due time for the Olympic games in 2008. For the system design and a reliable traction power supply the simulation software Sitras {sup registered} Sidytrac was used. The program incorporates all modules necessary for the overall system design and relating detailed investigations. Measurements during system integration test validated the simulation results. (orig.)

  1. Investigation on Development of Condition-Based Maintenance in Power Supply System

    Li Minghua; Yan Zhang; Liu Chunwen; Xue Suijing; Liu Xin; Wang Ben


    @@ To improve the operation reliability of power supply system in China, it is of great significance to know the status of condition-based maintenance (CBM) in the system and accumulate related experience in recent years. This paper analyzes the current modes of detection and repair,maintenance periods, the operation status of on-line monitoring devices equipped and the existing problems of them. The results show that there exists an urgent need in intensifying the quality control and inspection of on-line monitoring products at present.

  2. Enhancement of the power supply systems in RFX-mod towards 2 MA plasma current

    Novello, Luca, E-mail: [Consorzio RFX, Euratom-ENEA Association, Padova (Italy); Zamengo, Andrea; Ferro, Alberto; Zanotto, Loris; Barp, Marco; Cavazzana, Roberto; Finotti, Claudio; Recchia, Mauro; Gaio, Elena [Consorzio RFX, Euratom-ENEA Association, Padova (Italy)


    The recent start-up improvements brought to RFX-mod have allowed increasing the plasma current in the range 1.7-1.9 MA, but still they proved to be not sufficient to routinely and reliably reach higher values of plasma current that would be very useful for the present studies on enhanced confinement. The need for higher poloidal flux variation together with the overabundant available toroidal flux has led to the study of a rearrangement of the power supply system with the aim of increasing the first at the expenses of the latter. Thanks to the flexibility of the power supply system, composed of modular thyristor converters, the rearrangement has been easily obtained and the resulting enhanced poloidal flux capability scenario described in the paper allows a two step plasma current ramp-up. In order to increase as much as possible the plasma current up to the nominal value of 2 MA it is necessary to fully exploit the thyristor converter power capability, in particular in the first ramp-up phase. In the paper a detailed verification of their maximum performance is presented. The first results obtained after power supply reconfiguration are very good, with plasma current kept constant at about 2 MA for 100 ms. The enabled operation at very high plasma current requires also an optimization of the magneto hydro dynamics (MHD) mode coil power supplies that are required to provide higher current values. Therefore a dedicated study of their control system has been worked out, which allowed understanding how to increase as much as possible the output current without losing the dynamic performance, so keeping the efficiency in the control of dominant and secondary modes, which is essential to obtain good and reproducible discharges.

  3. American lifelines alliance efforts to improve electric power transmission reliability

    Nishenko, S.P.; Savage, W.U.; Honegger, D.G.; McLane, T.R.; ,


    A study was performed on American Lifelines Alliance (ALA) efforts to improve electric power transmission reliability. ALA is a public-private partnership project, with the goal of reducing risks to lifelines from natural hazards and human threat events. The mechanism used by ALA for developing national guidelines for lifeline systems is dependent upon using existing Standards Developing Organizations (SDO) accredited by the American National Standards Institute (ANSI) as means to achieve national consensus.

  4. Development of Power Supply System with Distributed Generators using Parallel Processing Method

    Hirose, Kenichi; Takeda, Takashi; Okui, Yoshiaki; Yukita, Kazuto; Goto, Yasuyuki; Ichiyanagi, Katsuhiro; Matsumura, Toshiro

    This paper describes a novel power system which consists of distributed energy resources (DER) with a static switch at the point of common coupling. Usage of the static switch with a parallel processing control is a new application of line interactive type uninterruptible power supply (UPS). In recent years, various ways of design, operation, and control methods have been studied in order to find more effective ways to utilize renewable energy and to reduce impact for environment. One of features of a proposed power system can interconnect to existing utility grid without interruption. Electrical power distribution to the loads by the power system can be continued between the states of interconnection and isolate operation seamlessly. The novel power system has other benefits such as more efficiency, demand site management, easy to control power system inside, improvement of reliability for power distribution, the minimum requirement of protection relays for grid interconnection. The proposed power system has been operated with the actual loads of 20kW in the campus of the Aichi Institute of Technology since 2007.

  5. Application of Wavelet-based Active Power Filter in Accelerator Magnet Power Supply

    Xiaoling, Guo


    As modern accelerators demand excellent stability to magnet power supply (PS), it is necessary to decrease harmonic currents passing magnets. Aim at depressing rappel current from PS in Beijing electron-positron collider II, a wavelet-based active power filter (APF) is proposed in this paper. APF is an effective device to improve the quality of currents. As a countermeasure to these harmonic currents, the APF circuit generates a harmonic current, countervailing harmonic current from PS. An active power filter based on wavelet transform is proposed in this paper. Discrete wavelet transform is used to analyze the harmonic components in supply current, and active power filter circuit works according to the analysis results. At end of this paper, the simulation and experiment results are given to prove the effect of the mentioned Active power filter.

  6. Investigation of the interaction between the power electronic circuit and power supply systems

    Beck, H.P.; Hermann, R.; Knuth, D.; Schwarzenau, R.


    Sources and consequences of the interaction between power electronics, power supply systems and telecommunications equipment were examined with the aid of measuring procedures and are presented here, using selected examples from traction and industrial drive technology. Apart from this the most important variables necessary to assess the power-line load, such as power factor, relative harmonic content and noise current, were calculated for conventional and low feedback effects converters taking various influencing factors into consideration. Another point of main emphasis in this research work is the analysis of the energy conditions prevailing in static converters for single-phase and three-phase supplies in particular in the case of pulsing methods for power control free of feedback effects. The methods and circuits for compensation and balancing of surge loads are described in detail in accordance with their technological significance. In the field of static high speed reactive power compensation with thyristor-controlled power capacitors new circuits and control techniques were developed. Work in the field of filter circuits reveals new application possibilities in power supply-systems with a high load of harmonic currents. Innovated noise current-reducing converter-wiring and controlled tuned capacitor banks can contribute to the prevention of mains resonance and other interferring factors influencing the performance of telecommunications equipment.

  7. Telecommunications equipment power supply in the Arctic by means of solar panels

    Terekhin, Vladimir; Lagunov, Alexey


    Development of the Arctic region is one of the priorities in the Russian Federation. Amongst other things, a reliable telecommunications infrastructure in the Arctic is required. Petrol and diesel generators are traditionally employed but their use has considerable environmental impact. Solar panels can be used as an alternative power source. The electricity generated will be sufficient to supply small-sized telecommunications equipment with total the power of over 80 watts. An installation consisting of the solar modules, a charge controller, batteries, an inverter and load was designed. Tests were conducted at Cape Desire of the Novaya Zemlya (island). The solar panels provided in excess of 80 W from 7 a.m. to 11 p.m. The batteries charge during this time was sufficient to provide the power supply for the communication equipment during the night, from 11 p.m. to 7 a.m. The maximum value of 638 W of the power generation was observed at 3 p.m. The minimum value of 46 W was at 4 a.m. The solar modules thus can be used during the polar day to power the telecommunications equipment.

  8. Booster main magnet power supply, present operation and potential future upgrades

    Bajon, E.; Bannon, M.; Marneris, I.; Danowski, G.; Sandberg, J.; Savatteri, S.


    The Brookhaven Booster Main Magnet Power Supply (MMPS) is a 24 pulse thyristor control supply, rated at 5500 Amps, +/-2000 Volts, or 3000 Amps, +/-6000 Volts. The power supply is fed directly from the power utility and the peak magnet power is 18 MWatts. This peak power is seen directly at the incoming ac line. This power supply has been in operation for the last 18 years. This paper will describe the present topology and operation of the power supply, the feedback control system and the different modes of operation of the power supply. Since the power supply has been in operation for the last 18 years, upgrading this power supply is essential. A new power supply topology has been studied where energy is stored in capacitor banks. DC to DC converters are used to convert the dc voltage stored in the capacitor banks to pulsed DC voltage into the magnet load. This enables the average incoming power from the ac line to be constant while the peak magnet power is pulsed to +/- 18 MWatts. Simulations and waveforms of this power supply will be presented.

  9. A study of DC-DC converters with MCT's for arcjet power supplies

    Stuart, Thomas A.


    Many arcjet DC power supplies use PWM full bridge converters with large arrays of parallel FET's. This report investigates an alternative supply using a variable frequency series resonant converter with small arrays of parallel MCT's (metal oxide semiconductor controlled thyristors). The reasons for this approach are to: increase reliability by reducing the number of switching devices; and decrease the surface mounting area of the switching arrays. The variable frequency series resonant approach is used because the relatively slow switching speed of the MCT precludes the use of PWM. The 10 kW converter operated satisfactorily with an efficiency of over 91 percent. Test results indicate this efficiency could be increased further by additional optimization of the series resonant inductor.

  10. A new digital pulse power supply in heavy ion research facility in Lanzhou

    Wang, Rongkun; Chen, Youxin; Huang, Yuzhen; Gao, Daqing; Zhou, Zhongzu; Yan, Huaihai; Zhao, Jiang; Shi, Chunfeng; Wu, Fengjun; Yan, Hongbin; Xia, Jiawen; Yuan, Youjin


    To meet the increasing requirements of the Heavy Ion Research Facility in Lanzhou-Cooler Storage Ring (HIRFL-CSR), a new digital pulse power supply, which employs multi-level converter, was designed. This power supply was applied with a multi H-bridge converters series-parallel connection topology. A new control model named digital power supply regulator system (DPSRS) was proposed, and a pulse power supply prototype based on DPSRS has been built and tested. The experimental results indicate that tracking error and ripple current meet the requirements of this design. The achievement of prototype provides a perfect model for HIRFL-CSR power supply system.

  11. Mobile hydraulic power supply. Liquid piston Stirling engine pump

    Ven, James D. van de [100 Institute Road, Department of Mechanical Engineering, Worcester Polytechnic Institute, Worcester, MA 01609 (United States)


    Conventional mobile hydraulic power supplies involve numerous kinematic connections and are limited by the efficiency, noise, and emissions of internal combustion engines. The Stirling cycle possesses numerous benefits such as the ability to operate from any heat source, quiet operation, and high theoretical efficiency. The Stirling engine has seen limited success due to poor heat transfer in the working chambers, difficulty sealing low-molecular weight gases at high pressure, and non-ideal piston displacement profiles. As a solution to these limitations, a liquid piston Stirling engine pump is proposed. The liquid pistons conform to irregular volumes, allowing increased heat transfer through geometry features on the interior of the working chambers. Creating near-isothermal operation eliminates the costly external heat exchangers and increases the engine efficiency through decreasing the engine dead space. The liquid pistons provide a positive gas seal and thermal transport to the working chambers. Controlling the flow of the liquid pistons with valves enables matching the ideal Stirling cycle and creates a direct hydraulic power supply. Using liquid hydrogen as a fuel source allows cooling the compression side of the engine before expanded the fuel into a gas and combusting it to heat the expansion side of the engine. Cooling the compression side not only increases the engine power, but also significantly increases the potential thermal efficiency of the engine. A high efficiency Stirling engine makes energy regeneration through reversing the Stirling cycle practical. When used for regeneration, the captured energy can be stored in thermal batteries, such as a molten salt. The liquid piston Stirling engine pump requires further research in numerous areas such as understanding the behavior of the liquid pistons, modeling and optimization of a full engine pump, and careful selection of materials for the extreme operating temperatures. Addressing these obtainable

  12. A new digital pulse power supply in heavy ion research facility in Lanzhou

    Wang, Rongkun, E-mail: [Institute of Modern Physics, Lanzhou, 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Chen, Youxin; Huang, Yuzhen; Gao, Daqing; Zhou, Zhongzu; Yan, Huaihai [Institute of Modern Physics, Lanzhou, 730000 (China); Zhao, Jiang; Shi, Chunfeng; Wu, Fengjun [Institute of Modern Physics, Lanzhou, 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Yan, Hongbin; Xia, Jiawen; Yuan, Youjin [Institute of Modern Physics, Lanzhou, 730000 (China)


    To meet the increasing requirements of the Heavy Ion Research Facility in Lanzhou-Cooler Storage Ring (HIRFL-CSR), a new digital pulse power supply, which employs multi-level converter, was designed. This power supply was applied with a multi H-bridge converters series-parallel connection topology. A new control model named digital power supply regulator system (DPSRS) was proposed, and a pulse power supply prototype based on DPSRS has been built and tested. The experimental results indicate that tracking error and ripple current meet the requirements of this design. The achievement of prototype provides a perfect model for HIRFL-CSR power supply system. -- Highlights: • The converters topology of series-parallel connection improves the power supply's performance. • The SOPC based on dual Nios II processors improves the real-time performance of system. • Pulse mode is implemented in digital power supply based on FPGA, with a smaller tracking error.

  13. Reactive Power Compensation and Harmonic Suppression for Power Supply System of HT-7U Superconductive Tokamak


    In this paper, a strategy for the reactive power compensation and harmonic suppression of the power supply system in HT-7U superconductive Tokamak is proposed. The optimizedapproach is given in the parameters design for passive filter. Also a controlling method with fastresponse time and good accuracy is put forward for the compensator, which is more suitable forthe dynamic load.PAGS: 84.70.+p ,52.55. Fa, 84.30. Vn

  14. Statistical Power Supply Dynamic Noise Prediction in Hierarchical Power Grid and Package Networks

    Piccinini, Gianluca; Graziano, Mariagrazia


    One of the most crucial high performance systems-on-chip design challenge is to front their power supply noise sufferance due to high frequencies, huge number of functional blocks and technology scaling down. Marking a difference from traditional post physical-design static voltage drop analysis, /a priori dynamic voltage drop/evaluation is the focus of this work. It takes into account transient currents and on-chip and package /RLC/ parasitics while exploring the power grid design solution s...

  15. Largest fluidized bed power plant unit for power and district heat supply for Berlin (Part 1)

    Abroell, G.; Bade, H.; Bietz, K.H.; Jahn, P. (ABB Kraftwerke AG, Mannheim (Germany))


    The Berlin Power and Light Company (Bewag) has decided to install, on the inner city site of Moabit, for the supply of electricity and district heating, a new unit with circulating atmospheric fluidized bed combustion. The plant will be designed for a thermal capacity of 240 MW. The basis for this decision, and also the technical implementation, will be made public.

  16. A Switching-Mode Power Supply Design Tool to Improve Learning in a Power Electronics Course

    Miaja, P. F.; Lamar, D. G.; de Azpeitia, M.; Rodriguez, A.; Rodriguez, M.; Hernando, M. M.


    The static design of ac/dc and dc/dc switching-mode power supplies (SMPS) relies on a simple but repetitive process. Although specific spreadsheets, available in various computer-aided design (CAD) programs, are widely used, they are difficult to use in educational applications. In this paper, a graphic tool programmed in MATLAB is presented,…

  17. Reliability Indicators of Urban Electric Network Schemes for Supply of Second and Third Category Consumers

    M. Korotkevich


    Full Text Available The paper considers two schemes of the urban distributive electric network for supply of the second and third category consumers for whom indicators of reliability have been determined.As for a network scheme of the 2nd category it has been determined that while installing low-oil and vacuum switches at a distributive point the most remote transformer substation has the highest non-availability  factor which is higher of the corresponding non-availability  factor of the nearest transformer substation by 1,21–1,23 fold  accordingly.As for a network scheme of the 3rd category consumers it has been obtained the data that reliability of consumers receiving supply from bus-bars of transformer substations with 0,38 kW voltage changes  significantly (by 1,2–1,9-fold while changing a breakpoint of the network with 10 kW voltage.

  18. Design and testing of a 320 MW pulsed power supply

    Schillig, J.B.; Boenig, H.J. [Los Alamos National Lab., NM (United States); Ferner, J.A. [National High Magnetic Field Lab., Tallahassee, FL (United States)] [and others


    For a 60 Tesla, 100 millisecond long pulse magnet five 64 MW (87.6 MVA) power converter modules have been installed. Each module provides a no-load voltage of 4.18 kV and a full load voltage of 3.20 kV at the rated current of 20 kA. The modules are connected to a 1,430 MVA/650 MJ inertial energy storage generator set, which is operated at 21 kV and frequencies between 60 and 42 Hz. They are designed to provide the rated power output for 2 seconds once every hour. Each module consists of two 21 kV/3.1 kV cast coil transformers and two 6-pulse rectifiers connected in parallel without an interphase reactor, forming a 12-pulse converter module. As far as possible standard high power industrial converter components were used, operated closer to their allowable limits. The converters are controlled by three programmable high speed controllers. In this paper the design of the pulsed converters, including control and special considerations for protection schemes with the converters supplying a mutually coupled magnet system, is detailed. Test results of the converters driving an ohmic-inductive load for 2 seconds at 20 kA and 3.2 kV are presented.

  19. Remote Area Power Supply (RAPS) load and resource profiles.

    Giles, Lauren (Energetics, Inc., Washington, DC); Skolnik, Edward G. (Energetics, Inc., Washington, DC); Marchionini, Brian (Energetics, Inc., Washington, DC); Fall, Ndeye K. (Energetics, Inc., Washington, DC)


    In 1997, an international team interested in the development of Remote Area Power Supply (RAPS) systems for rural electrification projects around the world was organized by the International Lead Zinc Research Organization (ILZRO) with the support of Sandia National Laboratories (SNL). The team focused on defining load and resource profiles for RAPS systems. They identified single family homes, small communities, and villages as candidates for RAPS applications, and defined several different size/power requirements for each. Based on renewable energy and resource data, the team devised a ''strawman'' series of load profiles. A RAPS system typically consists of a renewable and/or conventional generator, power conversion equipment, and a battery. The purpose of this report is to present data and information on insolation levels and load requirements for ''typical'' homes, small communities, and larger villages around the world in order to facilitate the development of robust design practices for RAPS systems, and especially for the storage battery component. These systems could have significant impact on areas of the world that would otherwise not be served by conventional electrical grids.

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

    Narumanchi, Sreekant


    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.

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

    Narumanchi, Sreekant


    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.

  2. Reliability of high power laser diodes with external optical feedback

    Bonsendorf, Dennis; Schneider, Stephan; Meinschien, Jens; Tomm, Jens W.


    Direct diode laser systems gain importance in the fields of material processing and solid-state laser pumping. With increased output power, also the influence of strong optical feedback has to be considered. Uncontrolled optical feedback is known for its spectral and power fluctuation effects, as well as potential emitter damage. We found that even intended feedback by use of volume Bragg gratings (VBG) for spectral stabilization may result in emitter lifetime reduction. To provide stable and reliable laser systems design, guidelines and maximum feedback ratings have to be found. We present a model to estimate the optical feedback power coupled back into the laser diode waveguide. It includes several origins of optical feedback and wide range of optical elements. The failure thresholds of InGaAs and AlGaAs bars have been determined not only at standard operation mode but at various working points. The influence of several feedback levels to laser diode lifetime is investigated up to 4000h. The analysis of the semiconductor itself leads to a better understanding of the degradation process by defect spread. Facet microscopy, LBIC- and electroluminescence measurements deliver detailed information about semiconductor defects before and after aging tests. Laser diode protection systems can monitor optical feedback. With this improved understanding, the emergency shutdown threshold can be set low enough to ensure laser diode reliability but also high enough to provide better machine usability avoiding false alarms.

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

    Narumanchi, Sreekant


    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.

  4. The influence of power in supply chain innovation; a case study of the Dutch wheat chain

    Pol, Hanneke; Visscher, Klaasjan


    The purpose of this article is to clarify the relation between the power structure of a supply chain and the possibilities to realize supply chain innovations. In an in-depth case study of the faltering start of an innovation trajectory in the Dutch wheat supply chain, we show that supply chain inno

  5. Development of high-stability magnet power supply

    Choi, W. S.; Kim, M. J.; Jeong, I. W.; Kim, D. E.; Park, H. C.; Park, K. H.


    A very stable (≤10 ppm) magnet power supply (MPS) is required in an accelerator to achieve acceptable beam dynamics. Many factors affect the stability of an MPS, so design of the MPS requires much attention to noise-reduction schemes and to good processing of the signals from the feedback stage. This paper describes some design considerations for an MPS installed and operated in the Pohang Accelerator Laboratory: (1) control method, (2) oversampling technology, (3) ground isolation between hardware modules and (4) low-pass filter design to reduce the switching noise and rectifier ripple components, and shows the stability of three designed devices. The MPS design considerations were verified and validated in simulations and experiments. This paper also shows the relationship between stability and measurement aperture time of digital voltage meter 3458 A to measure stability of a current.

  6. Development of high-stability magnet power supply

    Choi, W.S.; Kim, M.J.; Jeong, I.W. [Graduate School of Wind Energy, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673 (Korea, Republic of); Kim, D.E. [Pohang Accelerator Laboratory, Pohang University of Science and Technology, 80 Jigokro-127-beongil, Nam-gu, Pohang, Gyeongbuk 37673 (Korea, Republic of); Park, H.C. [Graduate School of Wind Energy, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673 (Korea, Republic of); Park, K.H. [Pohang Accelerator Laboratory, Pohang University of Science and Technology, 80 Jigokro-127-beongil, Nam-gu, Pohang, Gyeongbuk 37673 (Korea, Republic of)


    A very stable (≤10 ppm) magnet power supply (MPS) is required in an accelerator to achieve acceptable beam dynamics. Many factors affect the stability of an MPS, so design of the MPS requires much attention to noise-reduction schemes and to good processing of the signals from the feedback stage. This paper describes some design considerations for an MPS installed and operated in the Pohang Accelerator Laboratory: (1) control method, (2) oversampling technology, (3) ground isolation between hardware modules and (4) low-pass filter design to reduce the switching noise and rectifier ripple components, and shows the stability of three designed devices. The MPS design considerations were verified and validated in simulations and experiments. This paper also shows the relationship between stability and measurement aperture time of digital voltage meter 3458 A to measure stability of a current.

  7. Water supply pipe dimensioning using hydraulic power dissipation

    Sreemathy, J. R.; Rashmi, G.; Suribabu, C. R.


    Proper sizing of the pipe component of water distribution networks play an important role in the overall design of the any water supply system. Several approaches have been applied for the design of networks from an economical point of view. Traditional optimization techniques and population based stochastic algorithms are widely used to optimize the networks. But the use of these approaches is mostly found to be limited to the research level due to difficulties in understanding by the practicing engineers, design engineers and consulting firms. More over due to non-availability of commercial software related to the optimal design of water distribution system,it forces the practicing engineers to adopt either trial and error or experience-based design. This paper presents a simple approach based on power dissipation in each pipeline as a parameter to design the network economically, but not to the level of global minimum cost.

  8. Self-stabilizing unidirectional network algorithms by power-supply

    Afek, Y.; Bremler, A. [Tel-Aviv Univ. (Israel)


    Power-supply, a surprisingly simple and new general paradigm for the development of self-stabilizing algorithms in different models, is introduced. The paradigm is exemplified by developing simple and efficient self-stabilizing algorithms for leader election and either BFS or DFS spanning tree constructions, in strongly-connected unidirectional and bidirectional dynamic networks (synchronous and asynchronous). The different algorithms stabilize in O(n) time in both synchronous and asynchronous networks without assuming any knowledge about the network topology or size, where n is the total number of nodes. Following the leader election algorithms we present a generic self-stabilizing spanning tree and/or leader election algorithm that produces a whole spectrum of new and efficient algorithms for these problems. Two variations that produce either a rooted Depth First Search tree or a rooted Breadth First Search tree are presented.




    The Relativistic Heavy Ion Collider (RHIC) was commissioned in 1999 and 2000. The two RHIC rings require a total of 933 power supplies (PSs) to supply currents to highly inductive superconducting magnets. These units function as 4 main PSs, 237 insertion region (02) PSs, 24 sextupole PSs, 24 Gamma-T PSs, 8 snake PSs, 16 spin rotator PSs, and 620 correction PSs. PS reliability in this type of machine is of utmost importance because the IR PSs are nested within other IR PSs, and these are all nested within the main PSs. This means if any main or IR PS trips off due to a PS fault or quench indication, then all the IR and main PSs in that ring must follow. When this happens, the Quench Protection Assemblies (QPA's) for each unit disconnects the PSs from the circuit and absorb the stored energy in the magnets. Commissioning these power supplies and QPA's was and still is a learning experience. A summary of the major problems encountered during these first three RHIC runs will be presented along with solutions.

  10. 76 FR 4147 - Putnam-Cumberland, TN-Improve Power Supply


    ... Putnam-Cumberland, TN--Improve Power Supply AGENCY: Tennessee Valley Authority. ACTION: Notice of intent... supply improvements in the Putnam and Cumberland region of east-central Tennessee. The purpose of the... approximately 16,000 miles of transmission lines. TVA supplies bulk electric power to Cumberland and...

  11. Reliability Indices Utlization in Combined Heat and Power ( CHP Optimal Operation

    Hamed Hosseinnia


    Full Text Available The reason for using cogeneration more that heat and power separately is that, it is more efficient. In this paper the goal is finding the optimized CHP system utility size and thermal storage considering reliability limits of boiler and grid connected bus. Loss of Load Expectation (LOLE and Expected energy not supplied (EENS are considered as two reliability indices to insure the security of operation. Non-sequential Monte Carlo simulation method is introduced to the reliability assessment of CHP, and a normal distribution electrical load model is built to simulate the hourly electrical load. CHP model combined with a two-state reliability model is applied to Monte Carlo simulation method, and results show that the CHP reliability model works well with non-sequential Monte Carlo simulation. Non-Sequential Monte Carlo method is used to generate scenarios. Also in order to reduce computation time and due to the large number of scenarios, a scenario reduction technique is used. GAMS software is used for optimization process.

  12. Comparison of Power Supply Pumping of Switch-Mode Audio Power Amplifiers with Resistive Loads and Loudspeakers as Loads

    Knott, Arnold; Petersen, Lars Press


    Power supply pumping is generated by switch-mode audio power amplifiers in half-bridge configuration, when they are driving energy back into their source. This leads in most designs to a rising rail voltage and can be destructive for either the decoupling capacitors, the rectifier diodes...... in the power supply or the power stage of the amplifier. Therefore precautions are taken by the amplifier and power supply designer to avoid those effects. Existing power supply pumping models are based on an ohmic load attached to the amplifier. This paper shows the analytical derivation of the resulting...... waveforms and extends the model to loudspeaker loads. Measurements verify, that the amount of supply pumping is reduced by a factor of 4 when comparing the nominal resistive load to a loudspeaker. A simplified and more accurate model is proposed and the influence of supply pumping on the audio performance...

  13. Charging System of ECRH High-Voltage Power Supply and its Control System

    胡国富; 丁同海; 刘保华; 姜书方


    High-voltage power supply (HVPS) of Electron Cyclotron Resonance Heating(ECRH) for HT-7 and HT-7U is presently being constructed. The high voltage (100 kV) en-ergy of HVPS is stored in the capacitor banks, and they can power one or two gyrotrons. All theoperation of the charging system will be done by the control system, where the field signals areinterfaced to programmable logic controller (PLC). The use of PLC not only simplifies the controlsystem, but also enhances the reliability. The software written by using configuration softwareinstalled in the master computer allows for remote and multiple operator control, and the statusand data information is also remotely available.

  14. Reactive power control methods for improved reliability of wind power inverters under wind speed variations

    Ma, Ke; Liserre, Marco; Blaabjerg, Frede


    The thermal cycling of power switching devices may lead to failures that compromise the reliability of power converters. Wind Turbine Systems (WTS) are especially subject to severe thermal cycling which may be caused by the wind speed variations or power grid faults. This paper proposes a control...... in the most stressed devices. The possible model-based control system for the proposed method is demonstrated, designed and simulated based on the Three-level Neutral-Point- Clamped (3L-NPC) grid-connected converters. It is concluded that with the proposed reactive power control method, the junction...... method to relieve the thermal cycling of power switching devices under severe wind speed variations, by circulating reactive power among the parallel power converters in a WTS or among the WTS's in a wind park. The amount of reactive power is adjusted to limit the junction temperature fluctuation...

  15. A power supply error correction method for single-ended digital audio class D amplifiers

    Yu, Zeqi; Wang, Fengqin; Fan, Yangyu


    In single-ended digital audio class D amplifiers (CDAs), the errors caused by power supply noise in the power stages degrade the output performance seriously. In this article, a novel power supply error correction method is proposed. This method introduces the power supply noise of the power stage into the digital signal processing block and builds a power supply error corrector between the interpolation filter and the uniform-sampling pulse width modulation (UPWM) lineariser to pre-correct the power supply error in the single-ended digital audio CDA. The theoretical analysis and implementation of the method are also presented. To verify the effectiveness of the method, a two-channel single-ended digital audio CDA with different power supply error correction methods is designed, simulated, implemented and tested. The simulation and test results obtained show that the method can greatly reduce the error caused by the power supply noise with low hardware cost, and that the CDA with the proposed method can achieve a total harmonic distortion + noise (THD + N) of 0.058% for a -3 dBFS, 1 kHz input when a 55 V linear unregulated direct current (DC) power supply (with the -51 dBFS, 100 Hz power supply noise) is used in the power stages.

  16. Energy Harvesting Chip and the Chip Based Power Supply Development for a Wireless Sensor Network.

    Lee, Dasheng


    In this study, an energy harvesting chip was developed to scavenge energy from artificial light to charge a wireless sensor node. The chip core is a miniature transformer with a nano-ferrofluid magnetic core. The chip embedded transformer can convert harvested energy from its solar cell to variable voltage output for driving multiple loads. This chip system yields a simple, small, and more importantly, a battery-less power supply solution. The sensor node is equipped with multiple sensors that can be enabled by the energy harvesting power supply to collect information about the human body comfort degree. Compared with lab instruments, the nodes with temperature, humidity and photosensors driven by harvested energy had variation coefficient measurement precision of less than 6% deviation under low environmental light of 240 lux. The thermal comfort was affected by the air speed. A flow sensor equipped on the sensor node was used to detect airflow speed. Due to its high power consumption, this sensor node provided 15% less accuracy than the instruments, but it still can meet the requirement of analysis for predicted mean votes (PMV) measurement. The energy harvesting wireless sensor network (WSN) was deployed in a 24-hour convenience store to detect thermal comfort degree from the air conditioning control. During one year operation, the sensor network powered by the energy harvesting chip retained normal functions to collect the PMV index of the store. According to the one month statistics of communication status, the packet loss rate (PLR) is 2.3%, which is as good as the presented results of those WSNs powered by battery. Referring to the electric power records, almost 54% energy can be saved by the feedback control of an energy harvesting sensor network. These results illustrate that, scavenging energy not only creates a reliable power source for electronic devices, such as wireless sensor nodes, but can also be an energy source by building an energy efficient

  17. Energy Harvesting Chip and the Chip Based Power Supply Development for a Wireless Sensor Network

    Dasheng Lee


    Full Text Available In this study, an energy harvesting chip was developed to scavenge energy from artificial light to charge a wireless sensor node. The chip core is a miniature transformer with a nano-ferrofluid magnetic core. The chip embedded transformer can convert harvested energy from its solar cell to variable voltage output for driving multiple loads. This chip system yields a simple, small, and more importantly, a battery-less power supply solution. The sensor node is equipped with multiple sensors that can be enabled by the energy harvesting power supply to collect information about the human body comfort degree. Compared with lab instruments, the nodes with temperature, humidity and photosensors driven by harvested energy had variation coefficient measurement precision of less than 6% deviation under low environmental light of 240 lux. The thermal comfort was affected by the air speed. A flow sensor equipped on the sensor node was used to detect airflow speed. Due to its high power consumption, this sensor node provided 15% less accuracy than the instruments, but it still can meet the requirement of analysis for predicted mean votes (PMV measurement. The energy harvesting wireless sensor network (WSN was deployed in a 24-hour convenience store to detect thermal comfort degree from the air conditioning control. During one year operation, the sensor network powered by the energy harvesting chip retained normal functions to collect the PMV index of the store. According to the one month statistics of communication status, the packet loss rate (PLR is 2.3%, which is as good as the presented results of those WSNs powered by battery. Referring to the electric power records, almost 54% energy can be saved by the feedback control of an energy harvesting sensor network. These results illustrate that, scavenging energy not only creates a reliable power source for electronic devices, such as wireless sensor nodes, but can also be an energy source by building an

  18. Operation of SST-1 TF power supply during SST-1 campaigns

    Sharma, Dinesh Kumar, E-mail:; Vora, Murtuza M.; Ojha, Amit; Singh, Akhilesh Kumar; Bhavsar, Chirag


    Highlights: • SST-1 TF power supply is 12 pulse SCR converter circuit. • TF power supply protection, measurement and control scheme are explained. • Quench, emergency and normal shot process is explained and results of SST-1 campaigns are shown. • Dynamic control of TF current. • The paper shows the results of last ten SST-1 campaigns. - Abstract: SST-1 TF power supply provides the direct current for the required magnetic field of TF coil. TF power supply includes transformer, 12-pulse converter, bus bar, water-cooled cable, protection and measuring equipments, and isolator, VME DAC system and GUI software. TF power supply is operated through GUI software built in TCL/Tk. VME DAC system monitors the parameters, provides On/Off commands, voltage and current references and initiates predefined reference to emergency shutdown. The emergency shutdown is hardwired to TF power supply from central control. During quench power supply converter opens DCCB and dump resistor is connected in the circuit and VME DAC system acquires bus bar voltage, dump voltage and dump current. Operation of TF power supply also requires monitoring of SCR and transformer temperature and water flow rate of water-cooled cable during high current long pulse shot. Before start up of TF power supply a quench simulation is performed to check the readiness of protection. This paper describes pre startup operation, normal shot operation, emergency and quench process, dynamic control and complete shutdown operation of TF power supply.

  19. Long-Term Reliability of a Hard-Switched Boost Power Processing Unit Utilizing SiC Power MOSFETs

    Ikpe, Stanley A.; Lauenstein, Jean-Marie; Carr, Gregory A.; Hunter, Don; Ludwig, Lawrence L.; Wood, William; Iannello, Christopher J.; Del Castillo, Linda Y.; Fitzpatrick, Fred D.; Mojarradi, Mohammad M.; Chen, Yuan


    Silicon carbide (SiC) power devices have demonstrated many performance advantages over their silicon (Si) counterparts. As the inherent material limitations of Si devices are being swiftly realized, wide-band-gap (WBG) materials such as SiC have become increasingly attractive for high power applications. In particular, SiC power metal oxide semiconductor field effect transistors' (MOSFETs) high breakdown field tolerance, superior thermal conductivity and low-resistivity drift regions make these devices an excellent candidate for power dense, low loss, high frequency switching applications in extreme environment conditions. In this paper, a novel power processing unit (PPU) architecture is proposed utilizing commercially available 4H-SiC power MOSFETs from CREE Inc. A multiphase straight boost converter topology is implemented to supply up to 10 kilowatts full-scale. High Temperature Gate Bias (HTGB) and High Temperature Reverse Bias (HTRB) characterization is performed to evaluate the long-term reliability of both the gate oxide and the body diode of the SiC components. Finally, susceptibility of the CREE SiC MOSFETs to damaging effects from heavy-ion radiation representative of the on-orbit galactic cosmic ray environment are explored. The results provide the baseline performance metrics of operation as well as demonstrate the feasibility of a hard-switched PPU in harsh environments.

  20. Study on Instrument System Power Supply Program%仪表系统供电方案的研究



    提高仪表电源系统的可靠性,对大型化工生产装置安全稳定运行至关重要。详细介绍了不间断电源的种类及特点和主要仪表用电设备的供电特点,从用电类型和安全生产要求等几个方面考虑,提出有针对性的仪表供电系统方案和应用实例。实践证明,该仪表供电系统方案运行稳定、安全可靠、经济实用。%Improving reliability of instrument power supply system is very critical to safe and stable operation of large chemical plants. The type, character of UPS and power supply characteristics of major instruments with electricity consumption are introduced in details. From perspectives of electricity consumption type and requirement of safe production, a specific instrument power supply scheme and corresponding application example are proposed. The practice has proved that the power supply scheme is stable, safe, reliable, economical and practical.

  1. KLYNAC: Compact linear accelerator with integrated power supply

    Malyzhenkov, Alexander [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    Accelerators and accelerator-based light sources have a wide range of applications in science, engineering technology and medicine. Today the scienti c community is working towards improving the quality of the accelerated beam and its parameters while trying to develop technology for reducing accelerator size. This work describes a design of a compact linear accelerator (linac) prototype, resonant Klynac device, which is a combined linear accelerator and its power supply - klystron. The intended purpose of a Klynac device is to provide a compact and inexpensive alternative to a conventional 1 to 6 MeV accelerator, which typically requires a separate RF source, an accelerator itself and all the associated hardware. Because the Klynac is a single structure, it has the potential to be much less sensitive to temperature variations than a system with separate klystron and linac. We start by introducing a simpli ed theoretical model for a Klynac device. We then demonstrate how a prototype is designed step-by-step using particle-in-cell simulation studies for mono- resonant and bi-resonant structures. Finally, we discuss design options from a stability point of view and required input power as well as behavior of competing modes for the actual built device.

  2. State-of-the-art piezoelectric transformer-based switch mode power supplies

    Ekhtiari, Marzieh; Zhang, Zhe; Andersen, Michael A. E.


    Inductorless switch mode power supplies based on piezoelectric transformers are used to replace conventional transformers in high power density switch mode power supplies. Even though piezoelectric-based converters exhibit a high d egree of nonlinearity, it is desirable to use piezoelectric transfo...... discusses power supplies with the trend evaluation of piezoelectric transformer-based converter topologies and control methods. The challenges of piezoelectric transformers regarding soft switching capability and nonlinearity are addressed. This paper can be used as a guideline f or choosing a proper...... topology of piezoelectric-based switch mode power supply and a control method for the required application....

  3. Comprehensive automation and monitoring of MV grids as the key element of improvement of energy supply reliability and continuity

    Stanisław Kubacki


    Full Text Available The paper presents the issue of comprehensive automation and monitoring of medium voltage (MV grids as a key element of the Smart Grid concept. The existing condition of MV grid control and monitoring is discussed, and the concept of a solution which will provide the possibility of remote automatic grid reconfiguration and ensure full grid observability from the dispatching system level is introduced. Automation of MV grid switching is discussed in detail to isolate a faulty line section and supply electricity at the time of the failure to the largest possible number of recipients. An example of such automation controls’ operation is also presented. The paper’s second part presents the key role of the quick fault location function and the possibility of the MV grid’s remote reconfiguration for improving power supply reliability (SAIDI and SAIFI indices. It is also shown how an increase in the number of points fitted with faulted circuit indicators with the option of remote control of switches from the dispatch system in MV grids may affect reduction of SAIDI and SAIFI indices across ENERGA-OPERATOR SA divisions.

  4. Development and Testing of an Ultracapacitor Based Uninterruptible Power Supply (UPS) System

    Eichenberg, Dennis J.


    The NASA Glenn Research Center (GRC) initiated the development and testing of an ultracapacitor based uninterruptible power supply (UPS) system as a means to provide backup power for the many critical NASA applications. A UPS system typically utilizes batteries for energy storage. The battery is the most vulnerable part of the UPS system, requiring regular maintenance and replacement. Battery performance is also extremely temperature dependent. Ultracapacitors are ideal for UPS systems where long life, maintenance free operation, and excellent low temperature performance is essential. State of the art symmetric ultracapacitors were used for these tests. The ultracapacitors were interconnected in an innovative configuration to minimize interconnection impedance, and to provide voltage balancing. Ultracapacitors can be charged extremely rapidly and supply high current, which are essential characteristics for an effective UPS system. Charging ultracapacitors is significantly less complex than charging batteries since there is no chemical reaction occurring while charging ultracapacitors. The report concludes that the implementation of symmetric ultracapacitors in a UPS system can provide significant improvements in power system performance and reliability.

  5. ICCP cathodic protection of tanks with photovoltaic power supply

    Janowski Mirosław


    Full Text Available Corrosion is the result of the electrochemical reaction between a metal or composite material usually having conducting current properties. Control of corrosion related defect is a very important problem for structural integrity in ground based structures. Cathodic protection (CP is a technique to protect metallic structures against corrosion in an aqueous environment, it is employed intense on the steel drains in oil and gas industry, specifically to protect underground tanks and pipelines. CP is commonly applied to a coated structure to provide corrosion control to areas where the coating may be damaged. It may be applied to existing structures to prolong their life. There are two types of cathodic protection systems: sacrificial (galvanic anode cathodic protection (SACP; the other system is Impressed Current Cathodic Protection (ICCP. Majority of the structures protected employ impressed current system. The main difference between the two is that SACP uses the galvanic anodes which are electrochemically more electronegative than the structure to be protected - the naturally occurring electrochemical potential difference between different metallic elements to provide protection; ICCP uses an external power source (electrical generator with D.C. with inert anodes, and this system is used for larger structures, or where electrolyte resistivity is high and galvanic anodes cannot economically deliver enough current to provide protection. The essential of CP is based on two parameters, the evolution of the potential and the current of protection. A commonly accepted protection criterion used for steel is a potential value of minus 850 mV. ICCP system consist of anodes connected to a DC power source. As power sources may be used such as solar panels, wind turbines, etc. The object of this study is analysis of the possibilities and operating parameters of ICCP system supplied with photovoltaic solar panels. Photovoltaic generator made up of the

  6. 500 Watt Diesel Fueled TPV Portable Power Supply

    Horne, W. E.; Morgan, M. D.; Sundaram, V. S.; Butcher, T.


    A test-bed 500 watt diesel fueled thermophotovoltaic (TPV) portable power supply is described. The goal of the design is a compact, rugged field portable unit weighing less than 15 pounds without fuel. The conversion efficiency goal is set at 15% fuel energy to electric energy delivered to an external load at 24 volts. A burner/recuperator system has been developed to meet the objectives of high combustion air preheat temperatures with a compact heat exchanger, low excess air operation, and high convective heat transfer rates to the silicon carbide emitter surface. The burner incorporates a air blast atomizer with 100% of the combustion air passing through the nozzle. Designed firing rate of 2900 watts at 0.07 gallons of oil per hour. This incorporates a single air supply dc motor/fan set and avoids the need for a system air compressor. The recuperator consists of three annular, concentric laminar flow passages. Heat from the combustion of the diesel fuel is both radiantly and convectively coupled to the inside wall of a cylindrical silicon carbide emitter. The outer wall of the emitter then radiates blackbody energy at the design temperature of 1400°C. The cylindrical emitter is enclosed in a quartz envelope that separates it from the photovoltaic (PV) cells. Spectral control is accomplished by a resonant mesh IR band-pass filter placed between the emitter and the PV array. The narrow band of energy transmitted by the filter is intercepted and converted to electricity by an array of GaSb PV cells. The array consists of 216 1-cm × 1-cm GaSb cells arranged into series and parallel arrays. An array of heat pipes couple the PV cell arrays to a heat exchanger which is cooled by forced air convection. A brief status of the key TPV technologies is presented followed by data characterizing the performance of the 500 watt TPV system.

  7. Simulation as a key to success in power supply design and development

    Suur-Askola, S.; Laasonen, M.; Maeki, J. [Efore Muuntolaite Oy, Vantaa (Finland)


    This paper describes the design and development process of a power supply by using simulation methods. The simulation principles and results of a 40W power supply are provided including EMI, voltage and current rating verification as well as power loss approximation. (orig.) 8 refs.

  8. 33 CFR 150.710 - What are the requirements for supplying power to aids to navigation?


    ... supplying power to aids to navigation? 150.710 Section 150.710 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: OPERATIONS Aids to Navigation § 150.710 What are the requirements for supplying power to aids to navigation? The power of all...

  9. The power-supply control system in the device of acetylene production by H-plasma pyrolysis coal

    Chen, F.Y.; Zhang, M.; Fu, P.; Weng, P.D. [Chinese Academy of Sciences, Hefei (China)


    The device of acetylene production by hydrogen (H{sub 2}) plasma pyrolysis coal is examined and developed not only for studying the application of low temperature plasma but also for studying the clean use of coal. The power-supply control system is used to ensure supplying a steady energy to generate and maintain the plasma electric arc of the device. The hardware configuration and the software design of the system are described in this paper. Verified by experiments, this system can meet the requirements of real-time performance, reliability and extensibility for the device.

  10. The Power-Supply Control System in the Device of Acetylene Production by H-Plasma Pyrolysis Coal

    Chen, Feiyun; Zhang, Ming; Fu, Peng; Weng, Peide


    The device of acetylene production by hydrogen (H-) plasma pyrolysis coal is examined and developed not only for studying the application of low temperature plasma but also for studying the clean use of coal. The power-supply control system is used to ensure supplying a steady energy to generate and maintain the plasma electric arc of the device. The hardware configuration and the software design of the system are described in this paper. Verified by experiments, this system can meet the requirements of real-time performance, reliability and extensibility for the device.

  11. The new dc power supply system for the main ring magnets of the 28 GeV CERN proton synchrotron

    Jahn, K; Steckmann, E


    High overload capacity, low residual ripple, exact reproducibility of periodic current pulses and very great reliability in long-term duty are essential requirements for a modern power supply system for feeding beam-guide magnets. These requirements can be met with certainty and at reasonable cost by the use of high-performance single-anode mercury-arc converters with suitable electronic control and protective equipment. (4 refs).

  12. Navigating financial and supply reliability tradeoffs in regional drought management portfolios

    Zeff, Harrison B.; Kasprzyk, Joseph R.; Herman, Jonathan D.; Reed, Patrick M.; Characklis, Gregory W.


    Rising development costs and growing concerns over environmental impacts have led many communities to explore more diversified water management strategies. These "portfolio"-style approaches integrate existing supply infrastructure with other options such as conservation measures or water transfers. Diversified water supply portfolios have been shown to reduce the capacity and costs required to meet demand, while also providing greater adaptability to changing hydrologic conditions. However, this additional flexibility can also cause unexpected reductions in revenue (from conservation) or increased costs (from transfers). The resulting financial instability can act as a substantial disincentive to utilities seeking to implement more innovative water management techniques. This study seeks to design portfolios that employ financial tools (e.g., contingency funds and index insurance) to reduce fluctuations in revenues and costs, allowing these strategies to achieve improved performance without sacrificing financial stability. This analysis is applied to the development of coordinated regional supply portfolios in the "Research Triangle" region of North Carolina, an area comprising four rapidly growing municipalities. The actions of each independent utility become interconnected when shared infrastructure is utilized to enable interutility transfers, requiring the evaluation of regional tradeoffs in up to five performance and financial objectives. Diversified strategies introduce significant tradeoffs between achieving reliability goals and introducing burdensome variability in annual revenues and/or costs. Financial mitigation tools can mitigate the impacts of this variability, allowing for an alternative suite of improved solutions. This analysis provides a general template for utilities seeking to navigate the tradeoffs associated with more flexible, portfolio-style management approaches.

  13. Exploring current and projected tradeoffs between hydropower profitability and reliability of supply in the Alps

    Anghileri, D.; Castelletti, A.; Burlando, P.


    The recent spreading of renewable energy across Europe and the associated production variability and uncertainty are emerging challenges for hydropower system operation. Widely distributed and highly intermittent solar and wind power generation systems, along with feed-in-tariffs, at which they are remunerated, are threating the operation of traditional hydropower systems. For instance, in countries where the transition to a larger production by means of renewable power systems is a novel process, e.g. Switzerland, many hydropower companies are operating their reservoirs with low or no profits, claiming for a revision of the entire energy market system. This situation goes along with the problem of ensuring energy supply both nowadays and in the future, with changing energy demand and available water resources. In this work, we focus on a hydropower system in the Swiss Alps to explore how different operating policies can cope with both adequate energy supply and profitable operation under current and future climate and socio-economic conditions. We investigate the operation of the Mattmark reservoir in South-West Switzerland. Mattmark is a pumped reservoir of 98 106 m3 fed by a natural catchment of 37 km2 and contributing catchments, summing up to 51 km2, connected by several diversion channels. The hydrological regime, snow- and ice-melt dominated, has already experienced changes in the last decades due to glacier retreat and is expected to be strongly impacted by climate change in the future. We use Multi-Objective optimization techniques to explore current tradeoffs between profitability and secure supply. We then investigate how tradeoffs may evolve in time under different climate change projections and energy market scenarios. Results inform on the co-evolution of climate- and socio-economic induced variations, thus unveiling potential co-benefit situations to hydropower generation and providing insights to future energy market design.

  14. Versatile CAMAC power supply controller-monitor with built-in ramping and ripple monitor

    Kang, H.; Horelick, D.


    An integrated power supply controller-monitor has been designed and is in use to control large power supplies for SLC dc magnets. This single-width CAMAC module contains a 14-bit DAC, a 14-bit ADC, and several channels of optically coupled digital status and control signals. Additional features include built-in selectable ramping rates, self-test capabilities, and a ripple monitor circuit to measure ac ripple in the power supply current.

  15. Cooling Performance Test of the SCT LV&HV Power Supply Rack

    Böhm, J; Vacek, V


    The cooling performance test of the 52U rack, housing SCT LV&HV power supplies for 192 detector modules, being located in USA15 cavern, has been curried out. The rack was equipped with two air-water heat exchangers, air turbine, four vertical fan tray units under crates and horizontal fans in four Artesyn AC/DC power supply units. The resistive dummy loads for 192 power supply channels have been placed in four crates and housed in the adjacent rack.

  16. Power supply to the public grid with power plant standard; Netzeinspeisesystem im Kraftwerksstandard

    Seltmann, T.


    Siemens offers an new current inverter system which supplies solar power from large PV systems to the public grid in master-slave operation. The system is based on current inverter drives which have been used as serial products in industrial applications. [Deutsch] Siemens bietet jetzt ein Wechselrichtersystem an, das im Master-Slave-Betrieb den Solarstrom aus grossen PV-Anlagen ins Netz einspeist. Das System basiert auf Antriebsstromrichtern, die sich bereits als Serienprodukte in der industriellen Anwendung bewaehrt haben. (orig.)

  17. A Newly Developed Method for Computing Reliability Measures in a Water Supply Network

    Jacek Malinowski


    Full Text Available A reliability model of a water supply network has beens examined. Its main features are: a topology that can be decomposed by the so-called state factorization into a (relativelysmall number of derivative networks, each having a series-parallel structure (1, binary-state components (either operative or failed with given flow capacities (2, a multi-state character of the whole network and its sub-networks - a network state is defined as the maximal flow between a source (sources and a sink (sinks (3, all capacities (component, network, and sub-network have integer values (4. As the network operates, its state changes due to component failures, repairs, and replacements. A newly developed method of computing the inter-state transition intensities has been presented. It is based on the so-called state factorization and series-parallel aggregation. The analysis of these intensities shows that the failure-repair process of the considered system is an asymptotically homogenous Markov process. It is also demonstrated how certain reliability parameters useful for the network maintenance planning can be determined on the basis of the asymptotic intensities. For better understanding of the presented method, an illustrative example is given. (original abstract

  18. A Performance Improvement of Power Supply Module for Safety-related Controller

    Kim, Jong-Kyun; Yun, Dong-Hwa; Hwang, Sung-Jae; Lee, Myeong-Kyun; Yoo, Kwan-Woo [PONUTech Co., Seoul (Korea, Republic of)


    In this paper, in relation to voltage shortage state when power supply module is a slave mode, the performance improvement by modifying a PFC(Power Factor Correction) circuit is presented. With the modification of the PFC circuit, the performance improvement in respect of the voltage shortage state when the power supply module is a slave mode is checked. As a result, POSAFE-Q PLC can ensure the stability with the redundant power supply module. The purpose of this paper is to improve the redundant performance of power supply module(NSPS-2Q). It is one of components in POSAFE-Q which is a PLC(Programmable Logic Controller) that has been developed for the evaluation of safety-related. Power supply module provides a stable power in order that POSAFE-Q can be operated normally. It is possible to be mounted two power supply modules in POSAFE-Q for a redundant(Master/Slave) function. So that even if a problem occurs in one power supply module, another power supply module will provide a power to POSAFE-Q stably.

  19. Minimization of the transformer inter-winding parasitic capacitance for modular stacking power supply applications

    Nguyen-Duy, Khiem; Ouyang, Ziwei; Knott, Arnold


    In an isolated power supply, the inter-winding parasitic capacitance plays a vital role in the mitigation of common mode noise currents created by fast voltage transient responses. The lower the transformer inter-winding capacitance, the more immune the power supply is to fast voltage transient...... responses. This requirement is even more critical for modular stacking applications in which multiple power supplies are stacked. This paper addresses the issue by presenting a detailed analysis and design of an unconventional isolated power supply that uses a ring core transformer with a very low inter...

  20. Design of High-power VME Specification Power Supply System%一种大功率VME规范电源的设计



    Military information processor requires a high performance power supply with stable output, load protection, and data protection to adapt the severe variation in output of fore-power. We designed a high performance and high-power Versa Module Eurocard(VME) specification power supply which can work in the input voltage range of 18V~50V according to the requirement of a certain military information processor, and analyzed the polarity protection module, the power keeping module, and the power supply monitoring module. Test on the information processor illustrates that this power supply gains excellent universality and reliability, and stable performance. The one-slot power supply possesses the virtues of higher power density, less weight, higher efficiency, and intelligence.%军用信息处理机对电源要求很高,不仅要求电源的输出稳定,还要求其具有负载保护及数据保护措施,以适应初级电源的恶劣变化.本文结合雷载信息处理机的具体需求,设计了能够在18V~50V输入范围工作的军用VME规范电源,并对反接保护、功率保持及电源监控等功能模块进行了分析和原理说明.通过与信息处理机的搭载试验证明该电源有良好的通用性和可靠性,技术指标优良,在单槽空间内实现了高功率密度、低重量、高效率且智能化的高性能电源.

  1. Study on application of a high-speed trigger-type SFCL (TSFCL) for interconnection of power systems with different reliabilities

    Kim, Hye Ji; Yoon, Yong Tae


    Interconnection of power systems is one effective way to improve power supply reliability. However, differences in the reliability of each power system create a greater obstacle for the stable interconnection of power systems, as after interconnection a high-reliability system is affected by frequent faults in low reliability side systems. Several power system interconnection methods, such as the back-to-back method and the installation of either transformers or series reactors, have been investigated to counteract the damage caused by faults in the other neighboring systems. However, these methods are uneconomical and require complex operational management plans. In this work, a high-speed trigger-type superconducting fault current limiter (TSFCL) with large-impedance is proposed as a solution to maintain reliability and power quality when a high reliability power system is interconnected with a low reliability power system. Through analysis of the reliability index for the numerical examples obtained from a PSCAD/EMTDC simulator, a high-speed TSFCL with a large-impedance is confirmed to be effective for the interconnection between power systems with different reliabilities.

  2. Design and Analysis of the Poloidal Field Grid Power Supply System for the HT-7 Tokamak


    This paper reports a new project - the poloidal field (PF) grid power supply system to replace the ac flywheel generator power supply system on the basis of the present running parameters of the HT-7 poloidal field and the short-circuit capacity of our transformer substation.The designed parameters of the PF grid power supply system have been verified to meet the requirements of the heating field (HF) and the vertical field (VF). In the meantime, in order to reduce the disturbance to the local power grid, the device of reactive power and harmonic current compensation has been added. Experimental results have confirmed the feasibility of the PF grid power supply system. Compared with the ac flywheel generator, the PF grid power supply system has the advantages of lower noise, precise control, convenient maintenance, simple operation and cost savings.

  3. Proposal for the award of a blanket contract for the supply and maintenance of uninterruptable power supplies (UPS)


    This document concerns the award of a blanket contract for the supply and maintenance of uninterruptable power supplies (UPS). Following a market survey carried out among 75 firms in eighteen Member States, a call for tenders (IT-2746/ST) was sent on 7 April 2000 to nine firms in four Member States. By the closing date, CERN had received tenders from six firms in four Member States. The Finance Committee is invited to agree to the negotiation of a blanket contract with GUTOR (CH), the lowest bidder after realignment, for the supply and maintenance of uninterruptable power supplies for a total amount of 5 000 000 Swiss francs, not subject to revision until 31 December 2002. The firm has indicated the following distribution by country of the contract value covered by this adjudication proposal: DK?54.3%, CH?23.7%, IT?10%, DE?10%, IE?1% and JP?1%.

  4. Maximizing MST's inductive capability with a Bp programmable power supply

    Chapman, B. E.; Holly, D. J.; Jacobson, C. M.; McCollam, K. J.; Morin, J. C.; Sarff, J. S.; Squitieri, A.


    A major goal of the MST program is the advancement of inductive control for the development of both the RFP's fusion potential and, synergistically, the predictive capability of fusion science. This entails programmable power supplies (PPS's) for the Bt and Bp circuits. A Bt PPS is already in place, allowing advanced RFP operation and the production of tokamak plasmas, and a Bp PPS prototype is under construction. To explore some of the new capabilities to be provided by the Bp PPS, the existing Bt PPS has been temporarily connected to the Bp circuit. One key result is new-found access to very low Ip (20 kA) and very low Lundquist number, S (104). At this low S, simulation of RFP plasmas with the MHD code NIMROD is readily achievable, and work toward validation of extended MHD models using NIMROD is underway with direct comparisons to these MST plasmas. The full Bp PPS will also provide higher Ip and S than presently possible, allowing MST to produce plasmas with S spanning as much as five orders of magnitude, a dramatic extension of MST's capability. In these initial tests, the PPS has also increased five-fold MST's Ip flattop duration, to about 100 ms. This, coupled with the recently demonstrated PPS ability to drive large-amplitude sinusoidal oscillations in Ip, will allow tests of extended-duration oscillating field current drive, the goal of which is ac sustainment of a quasi-dc plasma current. Work supported by US DOE.

  5. Design of a New Switching Power Supply for the ATLAS TileCAL Front-End Electronics

    Drake, G; The ATLAS collaboration


    We present the design of an upgraded switching power supply for the front-end electronics of the ATLAS hadron tile calorimeter (TileCAL) at the LHC. The new design features significant improvement in noise, improved fault detection, and improved reliability, while retaining the compact size, water-cooling, output control, and monitoring features in this 300 KHz design. We discuss the steps taken to improve the design. We present the results from extensive radiation testing to qualify the design, including SEU sensitivity. We also present our reliability analysis. Production of 2400 new bricks for the detector is currently in progress, and we present preliminary results from the production checkout.

  6. Coupling long and short term decisions in the design of urban water supply infrastructure for added reliability and flexibility

    Marques, G.; Fraga, C. C. S.; Medellin-Azuara, J.


    The expansion and operation of urban water supply systems under growing demands, hydrologic uncertainty and water scarcity requires a strategic combination of supply sources for reliability, reduced costs and improved operational flexibility. The design and operation of such portfolio of water supply sources involves integration of long and short term planning to determine what and when to expand, and how much to use of each supply source accounting for interest rates, economies of scale and hydrologic variability. This research presents an integrated methodology coupling dynamic programming optimization with quadratic programming to optimize the expansion (long term) and operations (short term) of multiple water supply alternatives. Lagrange Multipliers produced by the short-term model provide a signal about the marginal opportunity cost of expansion to the long-term model, in an iterative procedure. A simulation model hosts the water supply infrastructure and hydrologic conditions. Results allow (a) identification of trade offs between cost and reliability of different expansion paths and water use decisions; (b) evaluation of water transfers between urban supply systems; and (c) evaluation of potential gains by reducing water system losses as a portfolio component. The latter is critical in several developing countries where water supply system losses are high and often neglected in favor of more system expansion.

  7. Simulation and reliability analysis of shunt active power filter based on instantaneous reactive power theory

    CUI Yu-long; LIU Hong; WANG Jing-qin; SUN Shu-guang


    This paper first discusses the operating principle ofinstantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink power system toolbox is used to simulate the system. In the simulation model, as the most common harmonic source, 3-phase thyfistor bridge rectifier circuit is constructed.The simulation results before and after the shunt active filter was switched to the system corresponding to different firing angles of the thyristors are presented and analyzed, which demonstrate the practicability and reliability of the proposed shunt active filter scheme.

  8. Power System Reliability Assessment by Analysing Voltage Dips on the Blue Horizon Bay 22KV Overhead Line in the Nelson Mandela Bay Municipality

    Lamour, B. G.; Harris, R. T.; Roberts, A. G.


    Power system reliability problems are very difficult to solve because the power systems are complex and geographically widely distributed and influenced by numerous unexpected events. It is therefore imperative to employ the most efficient optimization methods in solving the problems relating to reliability of the power system. This paper presents a reliability analysis and study of the power interruptions resulting from severe power outages in the Nelson Mandela Bay Municipality (NMBM), South Africa and includes an overview of the important factors influencing reliability, and methods to improve the reliability. The Blue Horizon Bay 22 kV overhead line, supplying a 6.6 kV residential sector has been selected. It has been established that 70% of the outages, recorded at the source, originate on this feeder.

  9. Power Supply System for the Atlas Experiment: Design Specifications, Implementation, Test and First Results

    Lazzaroni, M.; Citterio, M.; Latorre, S.; Lanza, A.; Cova, P.; Delmonte, N.; Giuliani, F.


    The planned upgrade of instrumentation sensitivity in the ATLAS experiment of the Large Hadron Collider (LHC), at CERN, calls for a new type of power distribution architecture. Moreover, power supplies require DC-DC power converters able to work in very hostile environment and maintaining high level of Reliability, Availability, Maintainability and Safety (denoted as RAMS requirements) during the experimental activity. Two main issues need to be discussed: first, electronic devices and equipment must operate in very high background of both charged and neutral particles and high static magnetic field and, second, the increase of the radiation background and the requirements of new front-end electronics are indeed incompatible with the current capability of the actual distribution system. The APOLLO R&D collaboration, funded by the Italian Istituto Nazionale di Fisica Nucleare (INFN), aims to study dedicated topologies of both distribution system and DC-DC power converters and to design, build and test demonstrators, developing the needed technology for the industrialization phase. The collaboration has designed a 3kW, 280V-12V converter (MC) based on the Switch in Line architecture (SIL), a DC to DC phase-shifted converter characterized by a disposition in line of the MOSFETs with good soft switching performances, and in the last year many steps have been taken to enhance the power dissipation and the reliability and to improve the general features of the designed converter. In particular a new water heat sink was designed on the basis of TFD simulation accounting for the layout of the specific converter. Experimental activities in order to characterize both thermal and electrical features of the MC confirm the correctness of the adopted design criteria.

  10. 数据中心的供配电双总线系统%This p The Dual bus System of Power Supply and Distribution for IDC

    林雪松; 胡冬冬


    aper introduces the advantage and configuration of the dual bus system of power supply and distribution solution of dif⁃ferent types, different power of uninterruptable power supply, and the reliability of this scheme, feasibility, maintainability, compar⁃ing with traditional power solutions.%该文介绍了不同型号、不同功率的不间断电源冗余双总线供电解决方案的优势和配置,并对本方案的可靠性、可行性、可维护性与传统供电方案进行比较。

  11. Supplying the Power Requirements to a Sensor Network Using Radio Frequency Power Transfer

    Steven Percy


    Full Text Available Wireless power transmission is a method of supplying power to small electronic devices when there is no wired connection. One way to increase the range of these systems is to use a directional transmitting antenna, the problem with this approach is that power can only be transmitted through a narrow beam and directly forward, requiring the transmitter to always be aligned with the sensor node position. The work outlined in this article describes the design and testing of an autonomous radio frequency power transfer system that is capable of rotating the base transmitter to track the position of sensor nodes and transferring power to that sensor node. The system’s base station monitors the node’s energy levels and forms a charge queue to plan charging order and maintain energy levels of the nodes. Results show a radio frequency harvesting circuit with a measured S11 value of −31.5 dB and a conversion efficiency of 39.1%. Simulation and experimentation verified the level of power transfer and efficiency. The results of this work show a small network of three nodes with different storage types powered by a central base node.

  12. 76 FR 57897 - Energy Conservation Program: Energy Conservation Standards for Certain External Power Supplies


    ... RIN 1904-AB57 Energy Conservation Program: Energy Conservation Standards for Certain External Power... exclude external power supplies used in specific applications from certain energy conservation standards prescribed under the Energy Policy and Conservation Act (EPCA). Congress enacted this exclusion,...

  13. Development of lead/acid batteries for domestic remote-area power supplies

    Rand, D. A. J.; Baldsing, W. G. A.

    In recent times, there has been a growing recognition of the need for more reliable RAPS systems, both in Australia and in other parts of the world. From the battery point of view, development has, in some instances, been encouraged by a "market push", and in others by a "technology pull". Some manufacturers are seeking to supply customers with batteries that are merely re-labelled motive-power types, others are offering new technologies. In either case, the suitability of the products is unclear because of the poor comprehension of the actual service requirements imposed on batteries in RAPS operations. In order to overcome this deficiency, CSIRO has set in motion a detailed schedule of laboratory and field studies aimed at gaining a greater understanding of battery performance under RAPS duties. It is hoped that the resulting information will lead to specific design criteria for such batteries.

  14. Wind-powered asynchronous AC/DC/AC converter system. [for electric power supply regulation

    Reitan, D. K.


    Two asynchronous ac/dc/ac systems are modelled that utilize wind power to drive a variable or constant hertz alternator. The first system employs a high power 60-hertz inverter tie to the large backup supply of the power company to either supplement them from wind energy, storage, or from a combination of both at a preset desired current; rectifier and inverter are identical and operate in either mode depending on the silicon control rectifier firing angle. The second system employs the same rectification but from a 60-hertz alternator arrangement; it provides mainly dc output, some sinusoidal 60-hertz from the wind bus and some high harmonic content 60-hertz from an 800-watt inverter.

  15. Novel Radio on Fiber Access Eliminating External Electric Power Supply at Base Station

    Tetsuya; Miki; Katsuyasu; Kawano; Nobuo; Nakajima; Naoto; Kishi; Masaru; Miyamoto; Tetsu; Aoki


    A novel Radio On Fiber(ROF) access is proposed and demonstrated which enables the pico-cell Base Station (BS) for high-speed wireless communications to eliminate external electric power supply facilities. We demonstrated 2.4-GHz band radio signal transmission through the BS without external electric power supply. The electrical power used for BS circuit is feeded by optical power over optical fiber from central station.

  16. Design of the dummy coil for magnet power supply

    Kim, Chang-Hwan, E-mail:; Choi, Jae-Hoon; Jin, Jong-Kook; Lee, Dong-Keun; Kong, Jong-Dea; Joung, Nam-Young; Kim, Sang-Tae; Kim, Young-Jin; Kim, Yang-Soo; Kwon, Myeun


    Highlights: • It is necessary to confirm safety of the MPS on a dummy coil before the operating it. • We selected and designed the water cooling type dummy coil to test on the MPS's rating (12.5 kA) test. • For the design of the dummy coil, we considered requirements about electrical, structural and water cooling. • We will test as the rating power after MPS upgrade and that test will do before every KSTAR campaign. -- Abstract: It is necessary to test it on a dummy coil, before using a magnet power supply (MPS) to energize a Poloidal Field (PF) coil in the Korea Superconducting Tokamak Advanced Research (KSTAR) device. The dummy coil should accept the same large current from the MPS as the PF coil and be within the capability of the utilities located at the KSTAR site. Therefore a coil design based on the characteristics of the MPS and other restrictive conditions needed to be made. There are three requirements to be met in the design: an electrical requirement, a structural requirement, and a water cooling requirement. The electrical requirement was that the coil should have an inductance of 40 mH. For the structural requirement, the material should be non magnetic. The coil support structure and water cooling manifold were made of SUS 304. The water cooling requirement was that there should be sufficient flow rate so that the temperature rise ΔT should not exceed 12 °C for operation at 12.5 kA for 5 min. Square cross-section hollow conductor with dimensions of 38.1 mm × 38.1 mm was used with a 25.4 mm center hole for cooling water. However, as a result of tests, it was found that the electrical and structural requirements were satisfied but that the water cooling was over designed. It is imperative that the verification will be redone for a test with 12.5 kA for 5 min.

  17. Reliability and cost evaluation of small isolated power systems containing photovoltaic and wind energy

    Karki, Rajesh

    Renewable energy application in electric power systems is growing rapidly worldwide due to enhanced public concerns for adverse environmental impacts and escalation in energy costs associated with the use of conventional energy sources. Photovoltaics and wind energy sources are being increasingly recognized as cost effective generation sources. A comprehensive evaluation of reliability and cost is required to analyze the actual benefits of utilizing these energy sources. The reliability aspects of utilizing renewable energy sources have largely been ignored in the past due the relatively insignificant contribution of these sources in major power systems, and consequently due to the lack of appropriate techniques. Renewable energy sources have the potential to play a significant role in the electrical energy requirements of small isolated power systems which are primarily supplied by costly diesel fuel. A relatively high renewable energy penetration can significantly reduce the system fuel costs but can also have considerable impact on the system reliability. Small isolated systems routinely plan their generating facilities using deterministic adequacy methods that cannot incorporate the highly erratic behavior of renewable energy sources. The utilization of a single probabilistic risk index has not been generally accepted in small isolated system evaluation despite its utilization in most large power utilities. Deterministic and probabilistic techniques are combined in this thesis using a system well-being approach to provide useful adequacy indices for small isolated systems that include renewable energy. This thesis presents an evaluation model for small isolated systems containing renewable energy sources by integrating simulation models that generate appropriate atmospheric data, evaluate chronological renewable power outputs and combine total available energy and load to provide useful system indices. A software tool SIPSREL+ has been developed which generates

  18. 47 CFR 15.102 - CPU boards and power supplies used in personal computers.


    ... computers. 15.102 Section 15.102 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.102 CPU boards and power supplies used in personal computers. (a... modifications that must be made to a personal computer, peripheral device, CPU board or power supply during...

  19. New 50 Hz Superconducting Power Supply for a 2 kA DC Magnet

    Chevtchenko, O.A.; ten Kate, Herman H.J.; Krooshoop, Hendrikus J.G.


    A new superconducting power supply able to operate directly from the mains voltage at a frequency of 50-60 Hz is under development in our institutes. It will be applied to power a separator magnet for iron ore recycling. The supply consists of a full wave superconducting converter, a `cold'

  20. Loss Performance Analysis of an Isolated Power Supply for Ultrafast Tracking Converters

    Nguyen-Duy, Khiem; Knott, Arnold; Andersen, Michael A. E.


    This paper presents the loss performance analysis of an isolated power supply that is designed for ultra-fast tracking converters. The results of the analysis provide insights into the operation of the proposed power supply, how each physical component contributes to the total loss, and how its e...

  1. 14 CFR 125.377 - Fuel supply: Turbine-engine-powered airplanes other than turbopropeller.


    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Fuel supply: Turbine-engine-powered... AIRCRAFT Flight Release Rules § 125.377 Fuel supply: Turbine-engine-powered airplanes other than... wind and other weather conditions expected, it has enough fuel— (1) To fly to and land at the...

  2. 77 FR 22472 - Energy Conservation Program: Energy Conservation Standards for Certain External Power Supplies...


    ... Part 430 RIN 1904-AB57 Energy Conservation Program: Energy Conservation Standards for Certain External... energy conservation standards for certain external power supplies to re-insert a table that had been... statutorily-prescribed energy conservation standards for all Class A external power supplies to meet....

  3. 47 CFR 15.32 - Test procedures for CPU boards and computer power supplies.


    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Test procedures for CPU boards and computer... FREQUENCY DEVICES General § 15.32 Test procedures for CPU boards and computer power supplies. Power supplies and CPU boards used with personal computers and for which separate authorizations are required to be...

  4. Thermal control of power supplies with electronic packaging techniques. [using low cost heat pipes


    The integration of low-cost commercial heat pipes in the design of a NASA candidate standard modular power supply with a 350 watt output resulted in a 44% weight reduction. Part temperatures were also appreciably reduced, increasing the environmental capability of the unit. A complete 350- watt modular power converter was built and tested to evaluate thermal performance of the redesigned supply.

  5. A Simple Power Management Scheme with Enhanced Stability for a Solar PV/Wind/Fuel Cell/Grid Fed Hybrid Power Supply Designed for Industrial Loads

    S. Saravanan


    Full Text Available This paper proposes a new power conditioner topology with an intelligent power management controller that integrates multiple renewable energy sources such as solar energy, wind energy, and fuel cell energy with battery and AC grid supply as backup to make the best use of their operating characteristics with better reliability than that could be obtained by single renewable energy source based power supply. The proposed embedded controller is programmed to perform MPPT for solar PV panel and WTG, SOC estimation and battery, maintaining a constant voltage at PCC and power flow control by regulating the reference currents of the controller in an instantaneous basis. The instantaneous variation in reference currents of the controller enhances the controller response as it accommodates the effect of continuously varying solar insolation and wind speed in the power management. It also prioritizes the sources for consumption to achieve maximum usage of green energy than grid energy. The simulation results of the proposed power management system with real-time solar radiation and wind velocity data collected from solar centre, KEC, and experimental results for a sporadically varying load demand are presented in this paper and the results are encouraging from reliability and stability perspectives.

  6. Performance and Reliability of Interface Materials for Automotive Power Electronics (Presentation)

    Narumanchi, S.; DeVoto, D.; Mihalic, M.; Paret, P.


    Thermal management and reliability are important because excessive temperature can degrade the performance, life, and reliability of power electronics and electric motors. Advanced thermal management technologies enable keeping temperature within limits; higher power densities; and lower cost materials, configurations and systems. Thermal interface materials, bonded interface materials and the reliability of bonded interfaces are discussed in this presentation.

  7. 76 FR 64082 - Mandatory Reliability Standards for the Bulk-Power System; Notice of Staff Meeting


    ... Energy Regulatory Commission Mandatory Reliability Standards for the Bulk-Power System; Notice of Staff...\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats. & Regs. ] 31,242... Discussion on the reliability issues relating to ``Single Point of Failure on Protection Systems,'' on...

  8. 75 FR 52528 - Mandatory Reliability Standards for the Bulk-Power System; Notice of Technical Conference


    ... Energy Regulatory Commission Mandatory Reliability Standards for the Bulk-Power System; Notice of... ] 61,053 (2007). \\2\\ Mandatory Reliability Standards for the Bulk Power System, 130 FERC ] 61,218... a frequency response requirement.'' \\3\\ \\1\\ Mandatory Reliability Standards for the...

  9. The power supply system model of the process submersible device with AC power transmission over the cable-rope

    Rulevskiy, V. M.; Bukreev, V. G.; Kuleshova, E. O.; Shandarova, E. B.; Shandarov, S. M.; Vasilyeva, Yu Z.


    A practical problem of power supply system modeling for the process submersible device with AC power transmission over the cable-rope was considered. The problem is highly relevant in developing and operation of submersible centrifugal pumps and submersibles. The results of modeling a symmetrical three-phase power supply system and their compliance with the real data are given at the paper. The obtained results in the mathematical and simulation models were similar.

  10. Operational reliability evaluation of restructured power systems with wind power penetration utilizing reliability network equivalent and time-sequential simulation approaches

    Ding, Yi; Cheng, Lin; Zhang, Yonghong


    and reserve provides, fast reserve providers and transmission network in restructured power systems. A contingency management schema for real time operation considering its coupling with the day-ahead market is proposed. The time-sequential Monte Carlo simulation is used to model the chronological...... with high wind power penetration. The proposed technique is based on the combination of the reliability network equivalent and time-sequential simulation approaches. The operational reliability network equivalents are developed to represent reliability models of wind farms, conventional generation...... characteristics of corresponding reliability network equivalents. A simplified method is also developed in the simulation procedures for improving the computational efficiency. The proposed technique can be used to evaluate customers’ reliabilities considering high penetration of wind power during the power...

  11. Proposal for the Award of a Contract for the Supply 1000 Quench Heater Power Supplies for the LHC


    This document concerns the award of a contract for the supply of 1000 quench heater power supplies for the LHC. Following a market survey carried out among 84 firms in fifteen Member States, a call for tenders (IT-3167/AB/LHC) was sent on 18 February 2003 to 10 firms in eight Member States. By the closing date, CERN had received 10 tenders from the 10 firms in eight Member States. The Finance Committee is invited to agree to the negotiation of a contract with EFACEC (PT), the lowest bidder, for the supply of 1000 quench heater power supplies for a total amount of 704 113 euros (1 042 018 Swiss francs), not subject to revision, with an option for additional purchases of up to 1000 quench heater power supplies, for an additional maximum amount of 704 113 euros (1 042 018 Swiss francs), not subject to revision, bringing the total amount to 1 408 226 euros (2 084 036 Swiss francs). The rate of exchange used is that stipulated in the tender. The firm has indicated the following distribution by country of the contr...

  12. The NC Power Supply Design of Large Current and Wide Frequency Pulse in SEAM

    Jianping Zhou


    Full Text Available There are a lot of ways to achieve large current pulse power supply, and the more common way is to adopt the inverter switching circuit to achieve pulse power supply. The core of the NC power supply design of large current and wide frequency pulse in SEAM is using two-stage modulation. Combined with inverter technology, DC chopper technology and NC technology, it not only can achieve the adjustability of the output pulse amplitude, but also can realize continuous adjustment of the output pulses and the duty cycle. The front stage of power supply uses DC/DC transformation circuit with the UC3879 integrated control chip as the core. With the microcontroller as the control core, the backward stage uses DC chopper circuit to achieve the NC power supply of multi-parameter adjustable output large current pulse.

  13. Regional power supply with decentral and renewable energy sources; Regionale Energieversorgung mit dezentralen und erneuerbaren Energien

    Bonow, Martin [Genossenschaftsverband, Neu-Isenburg/Zeppelinheim-Ost (Germany); George, Wolfgang [GenoPortal, Neu-Isenburg (Germany); Klement, Martin [Kassel Univ. (Germany). Fachbereich 6 - Architektur, Stadtplanung, Landschaftsplanung


    The contribution starts by assuming a region as a business organisation; on this basis, the authors develop the idea of a regional value-adding chain with regard to regional power supply. After presenting the central actors and their manner of integration, the contribution discusses concepts for sustainable power supply as well as the central parameters of such a development in terms of quality of life, attractivity of the region, future success of technologies, and criteria of value-adding. Finally, the implementation of regional power supply with the aid of a so-called 'balanced scorecard' is explained, which involves balancing of the various perspectives of the process up to the establishment of the final regional power supply concept. Finally, the contribution briefly discusses co-operative models for the establishment of a regional power supply concept. (orig.)

  14. Reliable multi period multi product supply chain design with facility disruption

    Mehdi Rafiei


    Full Text Available This paper presents a strategic multi segment, multi period and multi-product supply chain management to meet reliable networks for handling disruptions strike. We present a mixed-integer programming model whose objective is to minimize the expected cost composed of probability and cost of occurrence in each scenario. The proposed model of this paper considers time value of money for each operation and transportation cost. We attempt to minimize expected costs by considering the levels of inventory, back-ordering, the available machine capacity and labor levels for each source, transportation capacity at each transshipment node and available warehouse space at each destination. The problem is generalized by taking into account backup supplier with reserved capacity and backup transshipment node that, which satisfies demands at higher price without disruption facility. We use a priority-based genetic algorithms encoding to solve the proposed problem under multi period and multi product conditions. The performance of the proposed model is examined using some instances.

  15. High efficiency fuel cell based uninterruptible power supply for digital equipment

    Gonzales, James; Tamizhmani, Govindasamy

    Eliminating the ac-dc converter (such as a computer's power supply), in a dc system when using a fuel cell based uninterruptible power supply (UPS), serves several primary functions. Firstly, it eliminates the need for a dc-ac inverter, and secondly, it eliminates a usually highly inefficient component-the power supply. Multiple conversions result in multiple inefficiencies. By replacing the computer's ac power supply with a high efficiency dc power supply capable of operating directly from a fuel cell - and thereby eliminating the inverter - the overall efficiency of the UPS can be increased by 50% or more. This is essential considering that the primary function of a fuel cell based UPS is long-term operation of the system, and poor efficiency equates to higher fuel consumption. Furthermore, inefficient systems have greater power demands, and therefore a larger fuel cell stack is needed to power them. At the present cost of fuel cell systems, this is a considerable problem. The easiest way to accomplish a direct dc UPS is to replace the computer's ac-dc power supply with a dc-dc power supply.

  16. Evaluation of the Influence of the Logistic Operations Reliability on the Total Costs of a Supply Chain

    Lukinskiy Valery


    Full Text Available Nowadays in logistics integral processes between the material and related flows in supply chains are getting developed more and more. However, in spite of increasing volume of statistical data which reflect the integral processes, the influence evaluation issues of the logistic operations reliability indexes on the total logistics costs remain open and require the corresponding researches implementation.

  17. Technogeopologistics: Supply Networks and Military Power in the Industrial Age


    the German Western campaign were fully motorized .48 As a result, the vast majority of the German infantry marched into battle, supplied with horse...Germans simply had overextended their LOCs.51 In other words, the fast-moving German motorized divisions were in danger of outrunning their logistics...Creveld, Supplying War Hitler had a fascination with cars. The National Socialist movement highlighted the new Autobahn and the Volkswagen as

  18. A new complete model of switch-mode plasma cutting power supply

    Abdolreza Esmaeli; SUN Li(孙力); NIE Jian-hong(聂剑红)


    A complete model of switch-mode plasma cutting power supply and its simulation are developed. The full bridge isolated pulse width modulation (PWM) buck converter in continuous conduction mode (CCM) for high watt plasma power supply is approached. Reduced ripple current and improved power factor are achieved in the plasma power supply. With a PID control strategy, circuit responses become more stable and faster with low overshoot during load and current changing. The converter achieved high efficiency under 3 to 15kW load conditions.

  19. An Application of Six Sigma for Improving the Efficiency of Power Supply

    Chang-Hsien Hsu


    Full Text Available Implementing the Six Sigma control method is to use define, measure, analyze, improve and control (DMAIC framework to improve the process from the beginning, emphasize the process management, reduce the process time, eliminate the defects, and increase the passing rate. The aims of this study is to apply Six Sigma control method with DMAIC framework to shorten the power supply over time in order to enhance the power supply efficiency in T. power company (TPC. The result showed that the power supply over time was reduced from 66% to 30% in the Construction Work Second Section.

  20. Design and Implement of Low Ripple and Quasi-digital Power Supply

    Xiangli, Li; Yanjun, Wei; Hanhong, Qi; Yan, Ma

    A switch linearity hybrid power supply based on single chip microcomputer is designed which merged the merits of the switching and linear power supply. Main circuit includes pre-regulator which works in switching mode and series regulator which works in linear mode. Two-stage regulation mode was adopted in the main circuit of the power. A single chip computer (SCM) and high resolution of series D/A and A/D converters are applied to control and measurement which achieved continuous adjustable and low ripple constant current or voltage power supply

  1. Dynamic Power Management for Portable Hybrid Power-Supply Systems Utilizing Approximate Dynamic Programming

    Jooyoung Park


    Full Text Available Recently, the optimization of power flows in portable hybrid power-supply systems (HPSSs has become an important issue with the advent of a variety of mobile systems and hybrid energy technologies. In this paper, a control strategy is considered for dynamically managing power flows in portable HPSSs employing batteries and supercapacitors. Our dynamic power management strategy utilizes the concept of approximate dynamic programming (ADP. ADP methods are important tools in the fields of stochastic control and machine learning, and the utilization of these tools for practical engineering problems is now an active and promising research field. We propose an ADP-based procedure based on optimization under constraints including the iterated Bellman inequalities, which can be solved by convex optimization carried out offline, to find the optimal power management rules for portable HPSSs. The effectiveness of the proposed procedure is tested through dynamic simulations for smartphone workload scenarios, and simulation results show that the proposed strategy can successfully cope with uncertain workload demands.


    Choi, Uimin

    As power electronic systems have gradually gained an important status in a wide range of industrial applications, there are increasing demands to improve the reliability and robustness of power electronic systems. The power electronic systems consist of various components, and among them, power...... that kills IGBT modules. Therefore, in order to improve the reliability of power electronic systems, reliability research on reliability-critical components regarding the major critical stressors are needed. In this PhD project, various researches on reliability of the IGBT module are performed from...... component level to converter level. It is divided into two main parts: the first part, which consists of Chapters 2 and 3, is reliability studies of the IGBT module regarding thermal stresses and the second part, composed of Chapters 4 and 5, discusses strategies to improve the reliability and availability...

  3. A new topology of fuel cell hybrid power source for efficient operation and high reliability

    Bizon, Nicu


    This paper analyzes a new fuel cell Hybrid Power Source (HPS) topology having the feature to mitigate the current ripple of the fuel cell inverter system. In the operation of the inverter system that is grid connected or supplies AC motors in vehicle application, the current ripple normally appears at the DC port of the fuel cell HPS. Consequently, if mitigation measures are not applied, this ripple is back propagated to the fuel cell stack. Other features of the proposed fuel cell HPS are the Maximum Power Point (MPP) tracking, high reliability in operation under sharp power pulses and improved energy efficiency in high power applications. This topology uses an inverter system directly powered from the appropriate fuel cell stack and a controlled buck current source as low power source used for ripple mitigation. The low frequency ripple mitigation is based on active control. The anti-ripple current is injected in HPS output node and this has the LF power spectrum almost the same with the inverter ripple. Consequently, the fuel cell current ripple is mitigated by the designed active control. The ripple mitigation performances are evaluated by indicators that are defined to measure the mitigation ratio of the low frequency harmonics. In this paper it is shown that good performances are obtained by using the hysteretic current control, but better if a dedicated nonlinear controller is used. Two ways to design the nonlinear control law are proposed. First is based on simulation trials that help to draw the characteristic of ripple mitigation ratio vs. fuel cell current ripple. The second is based on Fuzzy Logic Controller (FLC). The ripple factor is up to 1% in both cases.

  4. Air Force Armament Laboratory (AFATL) battery power supply (BPS) operations and maintenance

    Delaney, J. R.; Lippert, J. R.; Herald, W. L.


    The successful operation of the AFATL BPS system is discussed in terms of its proven reliable performance record, flexibility to adapt to different test configurations, and relatively inexpensive operating maintenance costs per test. The BPS consists of 13,728 batteries, interconnecting buswork, and a power conditioning inductor. The system is subdivided into six modules, each divided into six gangs with its own gang switch, each gang containing 24 battery strings. Each module has its own main bus pair, with the negative bus common and the positive bus switched. The operational and performance history of the AFATL BPS has proven that this battery system is effective as a prime power supply for hypervelocity launcher research. Turn-around time between tests has generally been less than that required for the test article. The power capabilities of the BPS can easily be expanded to the design point of a 200 MJ energy store. This can be done by adding more modules of batteries and reconfiguring the inductor with its existing three auxiliary turns in series.

  5. System-level Reliability Assessment of Power Stage in Fuel Cell Application

    Zhou, Dao; Wang, Huai; Blaabjerg, Frede


    the lifetime model and the stress levels, the Weibull distribution of the power semiconductors lifetime can be obtained by using Monte Carlo analysis. Afterwards, the reliability block diagram can further be adopted to evaluate the reliability of the power stage based on the estimated power semiconductor...

  6. Transient Processes in Electric Power Supply System for Oil Terminal with Own Gas-Turbine Power Station

    A. M. Hаshimov


    Full Text Available The paper contains results of the investigations concerning influence of symmetrical and non-symmetrical short circuits at main power network on electric power supply system of a huge oil terminal which is powered by own gas-turbine power station. Calculations have been made in accordance with the IEC and IEEЕ requirements. Estimations for voltage level and distribution of short circuit current in the electric power supply system of the Sangachal oil terminal being operated in parallel with the AzerEnerji grid are presented in the paper

  7. Analysis and Optimization of Power Supply Structure Based on Markov Chain and Error Optimization for Renewable Energy from the Perspective of Sustainability

    Xiaomin Xu


    Full Text Available With the rapid development of renewable energy, power supply structure is changing. However, thermal power is still dominant. With the background in low carbon economy, reasonable adjustment and optimization of the power supply structure is the trend of future development in the power industry. It is also a reliable guarantee of a fast, healthy and stable development of national economy. In this paper, the sustainable development of renewable energy sources is analyzed from the perspective of power supply. Through the research on the development of power supply structure, we find that regional power supply structure development mode conforms to dynamic characteristics and there must exist a Markov chain in the final equilibrium state. Combined with the characteristics of no aftereffect and small samples, this paper applies a Markov model to the power supply structure prediction. The optimization model is established to ensure that the model can fit the historical data as much as possible. Taking actual data of a certain area of Ningxia Province as an example, the models proposed in this paper are applied to the practice and results verify the validity and robustness of the model, which can provide decision basis for enterprise managers.

  8. A preliminary investigation of the Topaz II reactor as a lunar surface power supply

    Polansky, G.F. [Sandia National Labs., Albuquerque, NM (United States); Houts, M.G. [Los Alamos National Lab., NM (United States)


    Reactor power supplies offer many attractive characteristics for lunar surface applications. The Topaz II reactor resulted from an extensive development program in the former Soviet Union. Flight quality reactor units remain from this program and are currently under evaluation in the United States. This paper examines the potential for applying the Topaz II, originally developed to provide spacecraft power, as a lunar surface power supply.

  9. To Question оf Using Power Reserve оf Power-and-Heat Supply Turbine Plants

    S. A. Kachan


    Full Text Available The paper considers possibilities and limitations of various methods for obtaining power re-serve at power-and-heat supply turbo-generator sets.Approximate values of specific heat rate and quantity of reserve power and rate of its obtaining for various turbine plants are given in the paper.

  10. Mathematical model for the power supply system of an autonomous object with an AC power transmission over a cable rope

    Rulevskiy, V. M.; Bukreev, V. G.; Shandarova, E. B.; Kuleshova, E. O.; Shandarov, S. M.; Vasilyeva, Yu Z.


    A modeling problem of the power system, which provides an AC power transmission to a submersible device over the conducting rope, was considered. The power supply system units and their parameters are described. The system multi-dimensional mathematical model in the variables state space with regard to the nonlinear characteristic of system elements is proposed.

  11. Design of high-pressure direct contact heater for promising power supply units: Experimental substantiation

    Somova, E. V.; Shvarts, A. L.; Turkin, A. V.


    The results of experimental studies of superheated steam condensation on feed water jets in a highpressure, direct-contact heat exchanger are presented. Direct contact feed water heater (DCFWH) can be used in a dual-flow diagram of a steam-power unit with ultrasupercritical steam parameters (35 MPa, 700/720°C). The direct contact feed water heater is included in the flow diagram of the II circuit in a promising power unit; it provides feed water heating to 340°C in all maintenance and emergency operation modes of the unit. The reliability of the high-pressure direct contact heater operation in this flow diagram is of major importance in relation to the danger of lead solidification in the tube space of the steam generator. Technical requirements to the design of the high-pressure direct contact heater for increasing the heat exchange efficiency are formulated based on the results of earlier studies with steam-water mixture as the heating medium. The results of studies of superheated steam condensation on jets presented in this study testify that feed water is additionally heated to the required temperature at the output of the installation. The influence of initial feed water parameters (outflow velocity and temperature) on the jet heating length is elucidated. The numerical approximation of the experimental data for determination of the jet heating length in the nominal and partial power unit loads is obtained. The results of the calculations are used to simplify the design of the water-supplying element for the direct contact feed water heater. The proposed design of direct contact feed water heater is characterized by simplicity and low metal intensity, which provides the installation reliability at the considered pressure level due to the minimum number of structural elements.

  12. Composite Energy Storage System with Photovoltaic Power Generation and Uninterruptible Power Supply Function

    Jung-Min Kwon


    Full Text Available A composite energy storage system (CESS that includes a photovoltaic (PV power generation and an uninterruptible power supply (UPS function is proposed. This system has three operating modes, namely, a grid-connected inverter mode, a grid-connected rectifier mode, and an islanding mode. This system is composed of a boost converter, a three-phase inverter/rectifier, a bidirectional DC/DC converter, and thyristor switches. The boost converter extracts maximum power from the PV panels and sends it to the DC-link. The bidirectional DC/DC converter is connected between the battery and the DC-link, which leads to an optimized charging/discharging operation. The three-phase inverter/rectifier transmits the power to and from the grid. Also, it operates as a UPS in the islanding mode. The thyristor switches are used for connecting/disconnecting between the grid and the AC load. A 15 kW prototype is implemented to verify the performance of the proposed system.

  13. Prognostics-Enabled Power Supply for ADAPT Testbed Project

    National Aeronautics and Space Administration — Ridgetop's role is to develop electronic prognostics for sensing power systems in support of NASA/Ames ADAPT testbed. The prognostic enabled power systems from...

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

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


    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

  15. Transitioning to Physics-of-Failure as a Reliability Driver in Power Electronics

    Wang, Huai; Liserre, Marco; Blaabjerg, Frede


    Power electronics has progressively gained important status in power generation, distribution and consumption. With more than 70% of electricity processed through power electronics, recent research endeavors to improve the reliability of power electronic systems to comply with more stringent...... constraints on cost, safety and availability in various applications. This paper serves to give an overview of the major aspects of reliability in power electronics and to address the future trends in this multidisciplinary research direction. The ongoing paradigm shift in reliability research is presented...... first. Then the three major aspects of power electronics reliability are discussed, respectively, which cover from physics-of-failure analysis of critical power elec-tronic components, state-of-the-art design for reliability process and robustness validation, and intelligent control and condition...

  16. Transitioning to Physics-of-Failure as a Reliability Driver in Power Electronics

    Wang, Huai; Liserre, Marco; Blaabjerg, Frede


    Power electronics has progressively gained important status in power generation, distribution and consumption. With more than 70% of electricity processed through power electronics, recent research endeavors to improve the reliability of power electronic systems to comply with more stringent...... constraints on cost, safety and availability in various applications. This paper serves to give an overview of the major aspects of reliability in power electronics and to address the future trends in this multidisciplinary research direction. The ongoing paradigm shift in reliability research is presented...... first. Then the three major aspects of power electronics reliability are discussed, respectively, which cover from physics-of-failure analysis of critical power elec-tronic components, state-of-the-art design for reliability process and robustness validation, and intelligent control and condition...

  17. Using operational data to estimate the reliable yields of water-supply wells

    Misstear, Bruce D. R.; Beeson, Sarah

    The reliable yield of a water-supply well depends on many different factors, including the properties of the well and the aquifer; the capacities of the pumps, raw-water mains, and treatment works; the interference effects from other wells; and the constraints imposed by ion licences, water quality, and environmental issues. A relatively simple methodology for estimating reliable yields has been developed that takes into account all of these factors. The methodology is based mainly on an analysis of water-level and source-output data, where such data are available. Good operational data are especially important when dealing with wells in shallow, unconfined, fissure-flow aquifers, where actual well performance may vary considerably from that predicted using a more analytical approach. Key issues in the yield-assessment process are the identification of a deepest advisable pumping water level, and the collection of the appropriate well, aquifer, and operational data. Although developed for water-supply operators in the United Kingdom, this approach to estimating the reliable yields of water-supply wells using operational data should be applicable to a wide range of hydrogeological conditions elsewhere. Résumé La productivité d'un puits capté pour l'adduction d'eau potable dépend de différents facteurs, parmi lesquels les propriétés du puits et de l'aquifère, la puissance des pompes, le traitement des eaux brutes, les effets d'interférences avec d'autres puits et les contraintes imposées par les autorisations d'exploitation, par la qualité des eaux et par les conditions environnementales. Une méthodologie relativement simple d'estimation de la productivité qui prenne en compte tous ces facteurs a été mise au point. Cette méthodologie est basée surtout sur une analyse des données concernant le niveau piézométrique et le débit de prélèvement, quand ces données sont disponibles. De bonnes données opérationnelles sont particuli

  18. Distributed Control of the Power Supply-Demand Balance

    Larsen, Gunn K. H.; van Foreest, Nicky D.; Scherpen, Jacquelien M. A.


    This paper aims to achieve a balance of power in a group of prosumers, based on a price mechanism, i.e., to steer the difference between the total production and consumption of power to zero. We first set the information network topology such that the prosumers exchange price (power) information wit

  19. Implementing PSA for Power Supply System of HFETR%HFETR供电系统概率安全评价

    周春林; 张江云; 郑大吉; 王文龙; 邹德光; 李子彦; 陈启兵


    反应堆供电系统失效可导致堆芯熔毁等严重事故后果.本工作应用 RiskSpectrum 软件,对高通量工程试验堆(简称 HFETR)供电系统开展概率安全评价(PSA)工作.通过整合部分法考虑共因故障,建立了以全场断电(SBO)为顶事件的系统故障树模型,并定量给出 HFETR发生 SBO 概率为7.49E-8,证明 HFETR现役供电系统安全可靠.同时,以供电系统模型及运行可靠性数据为基础,进行了割集、重要度、敏感度等分析,较全面地分析了现役供电系统的风险水平,为 HFETR供电系统变更、升级和改造提供了重要参考.%The failure of reactor Power Supply System could cause severe consequence like core damage. Employing the RiskSpectrum software, HFETR Power Supply System is analyzed by using Probability Safety Assessment (PSA ) methodology. Considering the Common Cause Failures (CCF)by employing Unified Partial Method (UPM),the power supply system PSA model is built via constructing the fault trees with the SBO as top event. Meanwhile,the consequentially quantity failure probability is presented as 7.49E-8,which is a proof of the power supply system is safety and reliable. By input the reliability data from the HFETR operation,the unavailability of power supply system is presented. Furthermore, the analysis also involves in the Minimal Cut Set (MCS)analysis,importance measures and sensitivity calculations. Those analysis present an overview of the current power supply system risk level, provide a considerable reference of the system change and update issues.

  20. Power Supply for a Manned International Asteroid Mission

    Weingartner, Stefan; Nahra, Henry K.; Kohout, Lisa L.; Larin, Max


    A feasibility study considering the exploitation of a near Earth asteroid was performed. The power requirements and proposed power systems for the crew vehicle, cargo vehicles, mining and processing equipment are described. A photovoltaic power system was selected to meet the 52.1 kWe and the 3.9 kWe power requirements of the crew and cargo vehicles, respectively. A nuclear power plant using a thermodynamic Rankine cycle with a total mass of 62.1 tons was chosen to provide the 7.225 MWe and the 5.5 MWth required for the mining and processing activities at the asteroid.

  1. Simulation and optimization of wind and diesel power supply systems

    Lukutin, B. V.; Shandarova, E. B.; Matukhin, D. L.; Igisenov, A. A.; Shandarov, S. M.


    The paper proposes an algorithm to optimize the structure and the choice of capacity of wind and diesel power units of the combined power plant, depending on the wind energy potential and electricity consumption of electrified facility. The algorithm is based on mathematical models of technical and economic characteristics of wind and diesel power plants as well as an optimization method of coordinate descent. The algorithm takes into account the structure of the combined power plant, changing modes of its operation, construction and operation costs of the power facility. The objective function of the algorithm is to minimize the cost of electricity generated.

  2. Power system reliability memento; Memento de la surete du systeme electrique



    The reliability memento of the French power system (national power transmission grid) is an educational document which purpose is to point out the role of each one as regards power system operating reliability. This memento was first published in 1999. Extensive changes have taken place since then. The new 2002 edition shows that system operating reliability is as an important subject as ever: 1 - foreword; 2 - system reliability: the basics; 3 - equipment measures taken in order to guarantee the reliability of the system; 4 - organisational and human measures taken to guarantee the reliability of the system; appendix 1 - system operation: basic concepts; appendix 2 - guiding principles governing the reliability of the power system; appendix 3 - international associations of transmission system operators; appendix 4 - description of major incidents.




    Full Text Available A high-voltage high-frequency power supply for ozone generation is presented in this paper. Ozone generation is intended to be used in air and in water disinfection. A power stage consisting of a single-phase full bridge inverter for regulating the output power, a current push-pull inverter (driver and a control circuit are described and analyzed. This laboratory build power supply using a high voltage ferrite transformer and a PIC microcontroller was employed to energize a dielectric barrier discharge (DBD ozone generator. The inverter working on the basis of control strategy is of simple structure and has a variation range of the working frequency in order to obtain the optimal frequency value. The experimental results concerning electrical characterization and water treatment using a cylindrical DBD ozone generator supplied by this power supply are given in the end.

  4. Design of the power supply system for the plasma current modulation on J-TEXT tokamak

    Zhang, M.; Shao, J.; Ma, S.X., E-mail:; Liang, X.; Yu, K.X.; Pan, Y.


    Highlights: • A modification scheme of heating field power supply system for plasma current modulation. • High-power fast control power supply with multilevel cascade circuit. • Restraining circulating current with coupled inductors in cyclic symmetric structure. - Abstract: In order to further study the influence of current modulation parameters on suppressing tearing instability, the plasma current should be modulated in a wider range. So a modification scheme is designed to improve the performance of ohmic heating power supply system on J-TEXT tokamak. A multilevel cascade circuit with carrier phase-shifted PWM technique has been proposed. Coupled inductors are connected in the form of cyclic symmetry to restrain the circulating current caused by multiple paralleled branches. The simulation proves this proposed current modulation power supply system matches output requirement and achieves good current sharing effect. Finally, a prototype is designed, and the experiment results can verify the correctness of the simulation model well.

  5. 系留气球不间断供电技术研究%Research on uninterrupted power supply technology for tethered balloon

    苗颖; 姜鲁华; 徐国宁


    Power supply system is an important part of tethered balloon,its normal operation is the key to ensure tethered balloon safety and reliability. Some special loading needs uninterrupted power supply. When the main power supply is malfunction, the emergency power is switched to supply system in seamless to achieve system and loading normal operation. The switching modes of common main power supply have the disadvantage of slow motion,long time consuming,complex circuit and low reliability. In combination with the features of tethered balloon power supply system,a simple and easy to implement uninterrupted power supply method is presented. By using this method,the balloon borne-electronic equipment can work stably,and the reliability is enhanced greatly. Simulation and related experiments prove that this power supply structure can realize uninterrupted power supply, and has higher reliability.%供电系统是系留气球的重要组成部分,其正常运行是保证系留气球安全可靠的关键,一些特殊载荷需要不间断供电,即当主供电出现问题时,需要无缝切换到备用电源以实现系统和载荷正常运行.常用主备电切换方式动作缓慢,耗时较长,并且电路复杂可靠性低,结合系留气球供电系统的特点,提出一种简单易实现的不间断供电方式,即在电磁继电器基础上,在备用电源支路上再连接一组开关管并配合小容量电容,当系统检测到电压异常后,开关管在几微秒内快速切换到备用电源,电磁继电器在开关管接通一段时间后也会切换到备份电池,此时备份电池通过两条通路供电给母线,不仅球载电子设备可以稳定工作,而且可靠性大大增加.经过仿真和相关实验,证明这种供电结构实现了不间断供电,并且具有较高的可靠性.

  6. Trading Relationship Performance and Market Power in Food Supply Chains

    Xhoxhi, Orjon

    that contribute to the exercise by intermediaries of these power dimensions. In the third paper a Structural Equation Modelling is employed to analyse the effects of intermediaries’ power on trading relationship performance between farmer and intermediaries. The analysis show that intermediaries’ exercise...... of power over farmers’ margin, leads to reduced relationship performance. On the other hand, when they exercise their power over farmers input selection activities or over harvesting and delivery activities the performance is improved. Furthermore, the result show that intermediaries’ power affects......The development of the agri-food industry has led to a considerable increase of intermediaries’ market power vis-à-vis farmers. There are studies and evidence that suggests that due to their power, intermediaries transfer risks and unexpected costs to farmers which compromise the innovation...

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

    Kostandyan, Erik; Sørensen, John Dalsgaard


    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...

  8. International standard for future automotive 42 V supply voltages (PowerNet)

    Bremer, Wolfgang

    The development of innovative automotive systems is determined by the demand for cut in fuel consumption and increase in fuel efficiency, reduction of environmental pollution and comfort improvement. A basic condition for such developments is the introduction of a 42 V power supply in future vehicles. The characteristics of future power supplies and the resulting consequences for the system, the components and the whole vehicle power supply architecture need standardisation in different areas. The electrical stress for the vehicle components is addressed in the standard ISO 21848 and this paper gives details about the status of the standardisation work.

  9. Voltage ripple compensation for grid connected electrolyser power supply using small DC link capacitor

    Török, Lajos; Mathe, Laszlo; Munk-Nielsen, Stig


    The purpose of this work was to investigate a three-phase-grid connected power supply using small DC link capacitor for electrolyser application. The hydrogen generation system requires low voltage and high current power supply. Thus the structure of the 3-phase power supply is defined as follows......: a three phase rectification, a small DC-link capacitor and a phase-shifted full-bridge converter with current doubler rectification. Design constraints and control problems are investigated. The advantages and problems caused by the use of small DC link capacitor are presented. The control of the system...

  10. New Design of a Low Cost Analogue Current Supply for Power LEDs

    Radu Bogdan Dragomir


    Full Text Available The present paper proposes an innovative and inductive ballast-based power LED supply. This new design LED powering solution is a cost-efficient alternative to high-end switching mode power supply (SMPS used to feed LED clusters. The current supply circuit topology will be explained. The AC component of the LED current is analysed both from the ballast inductance and the value of the DC filtering capacitor standpoint. The PSIM and MATLAB tools have been used to simulate the circuit output when different ballast voltage conditions will be applied. Transitory and steady-state driver performances have been taken into account.

  11. Research on the Defects Restraining Ability of Power Supply Transacting Electrocircuit

    GAO Jun; CHEN Chuan-bo


    Adopting the mechanism model and the system identification method, the power supply transacting electrocircuit (integrate manostat) is analyzed, and the restraining ability and the response for power supply transacting electrocircuit to overcome various battery defects are studied. The effects of the power supply yawp on the normal functions of the radio fuze are investigated. The research indicate that the shortcomings of the integration manostat as battery defects can be regarded as steady noise, and the restraining ability of the integration manostat to battery defects isn't less than 50 dB.

  12. Reliable design of a closed loop supply chain network under uncertainty: An interval fuzzy possibilistic chance-constrained model

    Vahdani, Behnam; Tavakkoli-Moghaddam, Reza; Jolai, Fariborz; Baboli, Arman


    This article seeks to offer a systematic approach to establishing a reliable network of facilities in closed loop supply chains (CLSCs) under uncertainties. Facilities that are located in this article concurrently satisfy both traditional objective functions and reliability considerations in CLSC network designs. To attack this problem, a novel mathematical model is developed that integrates the network design decisions in both forward and reverse supply chain networks. The model also utilizes an effective reliability approach to find a robust network design. In order to make the results of this article more realistic, a CLSC for a case study in the iron and steel industry has been explored. The considered CLSC is multi-echelon, multi-facility, multi-product and multi-supplier. Furthermore, multiple facilities exist in the reverse logistics network leading to high complexities. Since the collection centres play an important role in this network, the reliability concept of these facilities is taken into consideration. To solve the proposed model, a novel interactive hybrid solution methodology is developed by combining a number of efficient solution approaches from the recent literature. The proposed solution methodology is a bi-objective interval fuzzy possibilistic chance-constraint mixed integer linear programming (BOIFPCCMILP). Finally, computational experiments are provided to demonstrate the applicability and suitability of the proposed model in a supply chain environment and to help decision makers facilitate their analyses.

  13. Supply Chain Cooperation between Coal Enterprise and Electric Power Enterprise in China


    Based on the two-stage Stackelberg game method, value creation of supply chain cooperation between coal enterprise and power utilities is studied by formulating profit functions of coal and power enterprises and calculating the maximum profit. According to the analysis, it is found that the profit from supply chain cooperation between coal and power enterprises is more than that of non-cooperation. The cooperation is validated to be beneficial for both units; however, the profit is mainly taken by the power enterprise. Thus, it is necessary to set up the incentive mechanism to distribute cooperation value between coal and power enterprises to promote their continual cooperation.

  14. The Way to Relieve Tense Supply Situation of Power and Coal in China

    Lu Min


    This paper introduces the situation of coal and power production, the tense supply of powercoal and deteriorated coal quality in 2004, analyzes the causes of tense supply of power and coal, one ofwhich is due to the government regulated power tariff against rapid escalation of coal price that powerenterprises can hardly afford. It also presents some policy proposals to relieve the contradiction betweencoal and power, including to intensify macroscopic regulation between industries and regions, solve theproblem of power coal transportation and reduction or exemption of tax on coal industry and circulationlinks, through secondary distribution to regulate profit difference among industries.

  15. Reliable Direct Bond Copper Ceramic Packages for High Temperature Power Electronics Project

    National Aeronautics and Space Administration — The proposed program will develop highly reliable, hermetic, Si3N4 ceramic multichip modules to integrate commercially available SiC power devices to build power...

  16. Rural power supply with local management: Examples from Bolivia, India and Nepal

    Gerger, Aa.; Gullberg, M.


    Local management of rural power supply is being evaluated in a joint research project conducted by Tanzania Electric Supply Company Limited (TANESCO) and Stockholm Environment Institute (SEI) on new approaches to management and organization of rural electrification. The study is based on literature, and on data from eight visited local organizations for management of power supply in Bolivia (4), India (1) and Nepal (3). Common for these countries is that the national, rural electrification programmes have encountered difficulties. Governments have failed to generate enough funds from existing power supply systems to cover the cost for a continued rural electrification. In cases where large private companies exist, they have had few incentives for expanding into rural areas since it is often not profit making. A third category may be defined as local initiators to power supply, private or co-operative. In all these countries, locally managed power supply systems have developed as a complement to governmental and other large scale programmes. The national policies pertaining to rural power supply in general and local management thereof in particular are described for each country. From the study, it appears that local management of rural power supply is a feasible approach in developing countries. Local management of rural power supply can slightly lower the costs of electrification, and it may help accelerate the pace of load development in newly electrified areas. For successful local organizations though, the most significant factor appears to be local peoples` willingness to develop their own area. Important though, is that proper financial and technical assistance is provided the local organizations. Crucial for sound external assistance is that the national rural electrification policies are clear and consistent. 53 refs, 1 fig, 11 tabs

  17. Dynamics of global supply chain and electric power networks: Models, pricing analysis, and computations

    Matsypura, Dmytro

    In this dissertation, I develop a new theoretical framework for the modeling, pricing analysis, and computation of solutions to electric power supply chains with power generators, suppliers, transmission service providers, and the inclusion of consumer demands. In particular, I advocate the application of finite-dimensional variational inequality theory, projected dynamical systems theory, game theory, network theory, and other tools that have been recently proposed for the modeling and analysis of supply chain networks (cf. Nagurney (2006)) to electric power markets. This dissertation contributes to the extant literature on the modeling, analysis, and solution of supply chain networks, including global supply chains, in general, and electric power supply chains, in particular, in the following ways. It develops a theoretical framework for modeling, pricing analysis, and computation of electric power flows/transactions in electric power systems using the rationale for supply chain analysis. The models developed include both static and dynamic ones. The dissertation also adds a new dimension to the methodology of the theory of projected dynamical systems by proving that, irrespective of the speeds of adjustment, the equilibrium of the system remains the same. Finally, I include alternative fuel suppliers, along with their behavior into the supply chain modeling and analysis framework. This dissertation has strong practical implications. In an era in which technology and globalization, coupled with increasing risk and uncertainty, complicate electricity demand and supply within and between nations, the successful management of electric power systems and pricing become increasingly pressing topics with relevance not only for economic prosperity but also national security. This dissertation addresses such related topics by providing models, pricing tools, and algorithms for decentralized electric power supply chains. This dissertation is based heavily on the following

  18. Strategic stockpiling of power system supplies for disaster recovery

    Bent, Russell W [Los Alamos National Laboratory; Coffrein, Carleton [Los Alamos National Laboratory; Van Hentenryck, Pascal [BROWN UNIV


    This paper studies the Power System Stochastic Storage Problem (PSSSP), a novel application in power restoration which consists of deciding how to store power system components throughout a populated area to maximize the amount of power served after disaster restoration. The paper proposes an exact mixed-integer formulation for the linearized DC power flow model and a general column-generation approach. Both formulations were evaluated experimentally on benchmarks using the electrical power infrastructure of the United States and disaster scenarios generated by state-of-the-art hurricane simulation tools similar to those used by the National Hurricane Center. The results show that the column-generation algorithm produces near-optimal solutions quickly and produces orders of magnitude speedups over the exact formulation for large benchmarks. Moreover, both the exact and the column-generation formulations produce significant improvements over greedy approach and hence should yield significant benefits in practice.

  19. Trends in the use of digital technology for control and regulation of power supplies.

    Carwardine, J.; Lenkszus, F.


    Since the availability of computers, accelerator power supplies have relied on digital technology in some way, from such simple tasks as turning the supplies on and off to the supplying of computer-controlled references. However, advances in digital technology, both in performance and cost, allow considerably more than simple control and monitoring. This, coupled with increasing demand for higher performance and monitoring capabilities, has made it appealing to integrate such technology into power supply designs. This paper will review current trends in the use of such advanced technology as embedded DSP controllers, and the application of real-time algorithms to the regulation and control of power supplies for accelerators and other large-scale physics applications.

  20. Intelligent uninterruptible power supply system with back-up fuel cell/battery hybrid power source

    Zhan, Yuedong; Guo, Youguang; Zhu, Jianguo; Wang, Hua


    This paper presents the development of an intelligent uninterruptible power supply (UPS) system with a hybrid power source that comprises a proton-exchange membrane fuel cell (PEMFC) and a battery. Attention is focused on the architecture of the UPS hybrid system and the data acquisition and control of the PEMFC. Specifically, the hybrid UPS system consists of a low-cost 60-cell 300 W PEMFC stack, a 3-cell lead-acid battery, an active power factor correction ac-dc rectifier, a half-bridge dc-ac inverter, a dc-dc converter, an ac-dc charger and their control units based on a digital signal processor TMS320F240, other integrated circuit chips, and a simple network management protocol adapter. Experimental tests and theoretical studies are conducted. First, the major parameters of the PEMFC are experimentally obtained and evaluated. Then an intelligent control strategy for the PEMFC stack is proposed and implemented. Finally, the performance of the hybrid UPS system is measured and analyzed.


    Grigorash O. V.


    Full Text Available The article discusses a promising direction, aimed at improving the operational and technical characteristics of the autonomous power supply systems, through the use of a part of their gas piston power plants, wind pow-er and solar photovoltaic installations

  2. Power Supply Changes for NSTX Resistive Wall Mode Coils

    Ramakrishnan, S S.


    The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics 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. Prior to 2004, the NSTX power system was feeding twelve (12) circuits in the machine. In 2004 the Resistive Wall Mode (RWM) Coils were installed on the machine to correct error fields. There are six of these coils installed around the machine in the mid-plane. Since these coils need fast and accurate controls, a Switching Power Amplifier (SPA) with three sub-units was procured, installed and commissioned along with other power loop components. Two RWM Coils were connected in series and fed from one SPA sub-unit. After the initial RWM campaign, operational requirements evolved such that each of the RWM coils now requires separate power and control. Hence a second SPA with three sub-units has been procured and installed. The second unit is of improved design and has the controls and power components completely isolated. The existing thyristor rectifier is used as DC Link to both of the Switching Power Amplifiers. The controls for the RWM are integrated into the overall computer control of the DC Power systems for NSTX. This paper describes the design changes in the RWM Power system for NSTX.

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

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


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

  4. Reliability and performance studies of DC-DC conversion powering scheme for the CMS pixel tracker at SLHC

    Todri, A; Rivera, R; Kwan, S [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Perera, L, E-mail: [University of Mississippi, University, MS 38677 (United States)


    The upgrades of the Large Hadron Collider (LHC) introduce a significant challenge to the power distribution of the detectors. DC-DC conversion is the preferred powering scheme proposed to be integrated for the CMS tracker to deliver high input voltage levels and performing a step-down conversion nearby the detector modules. In this work, we propose a step-up/step-down powering scheme by performing voltage step up at the CAEN supply unit and voltage step down near the detector. We designed step-up converters and investigate the pixel performance and power loss on the FPIX power distribution system. Tests are performed using the PSI46 pixel readout chips on a forward pixel panel module and the DC-DC converters developed at CERN and Fermilab. Reliability studies include the voltage drop measurements on the readout chips and the power supply noise generated from the converter. Performance studies include pixel noise and threshold dispersion results. Comparison between step-down only and step-up/step-down conversion powering schemes are provided.

  5. A real time status monitor for transistor bank driver power limit resistor in boost injection kicker power supply

    Mi, J.; Tan, Y.; Zhang, W.


    For years suffering of Booster Injection Kicker transistor bank driver regulator troubleshooting, a new real time monitor system has been developed. A simple and floating circuit has been designed and tested. This circuit monitor system can monitor the driver regulator power limit resistor status in real time and warn machine operator if the power limit resistor changes values. This paper will mainly introduce the power supply and the new designed monitoring system. This real time resistor monitor circuit shows a useful method to monitor some critical parts in the booster pulse power supply. After two years accelerator operation, it shows that this monitor works well. Previously, we spent a lot of time in booster machine trouble shooting. We will reinstall all 4 PCB into Euro Card Standard Chassis when the power supply system will be updated.

  6. Assessing Resilience in Power Grids as a Particular Case of Supply Chain Management


    grids share basic characteristics with Supply Chain Management. This thesis presents a linear programming model to assess power grid resilience as a...particular case of Supply Chain Management. Since resilient behavior is not an individual or specific system’s attribute but a holistic phenomenon based

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

    During the applications change to all fields of engineering, the discipline has, over the years, ... Characterization of the failure rate as a random variable .... the reliability performance is defined as the conditional probability that the system ...

  8. Reliability Evaluation of Power System Considering Voltage Stability and Continuation Power Flow

    R. K. Saket


    Full Text Available This article describes the methodology for evaluation of the reliability of an composite electrical power system considering voltage stability and continuation power flow, which takes into account the peak load and steady state stability limit. The voltage stability is obtained for the probable outage of transmission lines and removal of generators along with the combined state probabilities. The loss of load probabilities (LOLP index is evaluated by merging the capacity probability with load model. State space is truncated by assuming the limits on total numbers of outages of generators and transmission lines. A prediction correction technique has been used along with one dimensional search method to get optimized stability limit for each outage states. The algorithm has been implemented on a six-bus test system.

  9. Engineering Design of the ITER AC/DC Power Supply System

    Oh, B. H.; Lee, K. W.; Chang, D. S.; Jin, J. T.; Hwang, C. K.


    To design high power pulse power supplies, especially in huge power supplies have not designed till now, it is necessary to analyze a system's characteristics and relations with another systems as well as to know high voltage, high current control technologies. Contents of this project are; - Analysis of the changed designs of the AC/DC converters. - Setup of the PSIM model for the calculation of the junction temperature of the converter thyristors. - Finalize the converter's simulation modules and estimate the parallel number of an arm for each converter. - Fix the protection sequence and make a simulation. - Stability check of the power distribution system against the reactive power effect. - Design of small size hardware AC/DC converter. The results of these studies may used as one of references for practical designs of the power supplies and also used for developing Tokamak type fusion reactors in the future

  10. Vehicle roof with solar power supply and contact device. Fahrzeugdach mit Solarstromquelle und Kontakteinrichtung

    Paetz, W.; Meiler, K.; Schumacher, T.; Bienert, H.; Hirschberger, A.; Pfisterer, H.; Hoeller, M.


    Vehicle roof with at least one cover, carrying a solar power supply for optional covering or at least for partial uncovering of a roof opening. In addition, with at least one load driven by the solar power supply which is arranged separately from the cover and with a contact device for establishing of an electric connection between the solar power supply and the load. The contact device is designed as a switching configuration and the cover is a part of this switching configuration, so that depending on the adjustment motion of the cover, the load is connected to the solar power supply in one or several predetermined cover positions, and is disconnected in all other covert positions.

  11. AC Power Supply for Wobbler Magnet of the MC-50 Cyclotron

    Kim, Yu-Seok; Kang, Bong-Koo; Lee, Hong-Gi; Park, Ki-Hyeon; Wha Chung, Chin; Woo Lee, Wol


    The MC-50 cyclotron (k=50) produces the ion beam for nuclear physics, chemistry, and applied researches in Korea. It has a small beam diameter with Gaussian beam shape, whereas many users want a beam irradiation on a large target. A wobbler magnet and an AC power supply were designed and constructed to meet the users' requirement. The power supply has two independently operating channels for the vertical and horizontal coils of the wobbler magnet. The frequency of the AC power supply for both coils is programmable from 1 to 20 Hz in a step of 1 Hz, and the maximum rms output current is 12 A. Various properties of the power supply and experimental results are given in the paper.



    As part of the design of a new emergency lighting system for the CERN accelerator complex a new design for a radiation resistant power supply has been produced. The design is available from the Open Hardware Repository.

  13. Power supply design for the filament of the high-voltage electron accelerator

    Zhang, Lige; Yang, Lei; Yang, Jun, E-mail:; Huang, Jiang; Liu, Kaifeng; Zuo, Chen


    The filament is a key component for the electron emission in the high-voltage electron accelerator. In order to guarantee the stability of the beam intensity and ensure the proper functioning for the power supply in the airtight steel barrel, an efficient filament power supply under accurate control is required. The paper, based on the dual-switch forward converter and synchronous rectification technology, puts forward a prototype of power supply design for the filament of the high-voltage accelerator. The simulation is conducted with MATLAB-Simulink on the main topology and the control method. Loss analysis and thermal analysis are evaluated using the FEA method. Tests show that in this prototype, the accuracy of current control is higher than 97.5%, and the efficiency of the power supply reaches 87.8% when the output current is 40 A.

  14. The role of wind energy in the programme of power supply of northern Russia territories

    Bezroukikh, P. [Ministry for Fuel and Energy, Moscow (Russian Federation)


    In this article examined technical, management and economic problems has been arising during working out of above mentioned Power Supply Programm based on the renewable energy sources usage and proved the leading role of wind energy in this Programm. (author)

  15. Control system of HLS transport line and Linac focusing power supplies


    The control system of transport line and Linac focusing power supplies of Hefei Light Source was built upon Experimental Physics and Industrial Control System. The hardware construction, software design and performance test of the control system are described.

  16. Performance and modelling of 70kVdc power supply with solid-state crowbar

    Yellamraju, Sham Sunder Srinivas, E-mail: [Institute for Plasma Research, BHAT, Gandhinagar 382428 (India); Kulkarni, Sanjay V. [Institute for Plasma Research, BHAT, Gandhinagar 382428 (India)


    The experimental activities of tokamak research involve development of high power RF and microwave sources for fusion related heating and current drive applications. High power RF and microwave tubes like Klystron, Gyrotron and Tetrode are in general operated with high voltage DC power supplies. These HVDC power supplies of the order of 70 kVdc, must be equipped with necessary arc fault protection in addition to general over current and over voltage protection. The arc fault protection must act within few microseconds to prevent permanent damage to the RF tube, window, etc. When an arc fault is detected, output voltage of the DC power supply is short circuited using a crowbar device (generally Ignitron, Thyratron, thyristor, rail-gap, etc.) that operates in few microseconds. This diverts the fault current from the load to crowbar device, thereby protecting the load. This is necessary as conventional protection in the power supply input takes ∼100 ms to switch-off. The crowbar device must be able to take the fault current till the circuit breaker placed at power supply input is switched off. The arc fault protection is tested for its effectiveness by “wire-burn” test. Full power short circuit of ∼1.5 MW DC power supply puts enormous stress on the power supply, utility and the crowbar, therefore frequent wire-burn testing is to be avoided. This report presents simulation of wire-burn test using PSIM software. Optimization of the component values without conducting actual wire-burn test could be achieved.

  17. Design for Reliability of Power Electronics for Grid-Connected Photovoltaic Systems

    Yang, Yongheng; Sangwongwanich, Ariya; Blaabjerg, Frede


    Power electronics is the enabling technology for optimizing energy harvesting from renewable systems like Photovoltaic (PV) and wind power systems, and also for interfacing grid-friendly energy systems. Advancements in the power semiconductor technology (e.g., wide band-gap devices) have pushed...... the conversion efficiency of power electronics to above 98%, where however te reliability of power electronics is becoming of high concern. Therefore, it is important to design for reliable power electronic systems to lower the risks of many failures during operation; otherwise will increase the cost...... as well as to design for high reliability at an early stage. Knowhow of the loading in power electronics in harsh operating environments (e.g., fluctuating ambient temperature and solar irradiance) is important for life-time prediction, as the prerequisite of Deign for Reliability (DfR). Hence...

  18. Impacts of Contingency Reserve on Nodal Price and Nodal Reliability Risk in Deregulated Power Systems

    Zhao, Qian; Wang, Peng; Goel, Lalit


    The deregulation of power systems allows customers to participate in power market operation. In deregulated power systems, nodal price and nodal reliability are adopted to represent locational operation cost and reliability performance. Since contingency reserve (CR) plays an important role...... in reliable operation, the CR commitment should be considered in operational reliability analysis. In this paper, a CR model based on customer reliability requirements has been formulated and integrated into power market settlement. A two-step market clearing process has been proposed to determine generation...... and CR allocation. Customers' nodal unit commitment risk and nodal energy interruption have been evaluated through contingency analysis. Customers' reliability cost including reserve service cost and energy interruption cost have also been evaluated....

  19. Decentral power stores. Key components of future power supply concepts; Dezentrale Energiespeicher. Schluesselkomponenten fuer die Stromversorgung der Zukunft

    Huschke, Reinhard


    The book presents the most relevant power storage technologies, i.e. their advantages, shortcomings and possible applications. The focus is on decentral power stores that can be used wherever electric power must be stored, independent of local conditions. Although this concept does not play much of a role today, it will become more relevant in the context of increasingly decentral power supply. For 2020, a minimum share of 30 percent renewable energy in German power supply is required by law, while other scenarios assume an even bigger share. The present storage reserve capacity will not be sufficient for this. The book also goes into the applications of power storage systems in the fields of electromobility and in future, more decentral power grids. (orig.)

  20. Design of a System for Auto-patrolling Power Supplies and Displaying Beam Status In HIRFL


    A practical application for patrolling the device’s status and displalying beam status of HIRFL has been described.With regard to the kinds of the controlled devices,the system consists of two parts:First,the alarm system is applied to monitor all power supplies,which are decomposed into six groups in accordance with their positions for the convenience of user’s operation.The amount of magnet lens and power supplies of pre-beam