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Three first-generation Brayton cycle engine types were studied for solar application: a near-term open cycle (configuration A), a near-term closed cycle (configuration B), and a longer-term open cycle (configuration C). A parametric performance analysis was carried out to select engine designs for the three configurations. The interface requirements for the Brayton cycle engine/generator and solar receivers were determined. A technology assessment was then carried out to define production costs, durability, and growth potential for the selected engine types.

This presentation will be given at the AIAA Electric Hybrid-Electric Power Propulsion Workshop on July 29, 2016. The workshop is being held so the AIAA can determine how it can support the introduction of electric aircraft into the aerospace industry. This presentation will address the needs of the community within the industry that advocates the use of powered-lift as important new technologies for future aircraft and air transportation systems. As the current chairman of the VSTOL Aircraft Systems Technical Committee, I will be presenting generalized descriptions of the past research in developing powered-lift and generalized observations on how electric and hybrid-electric propulsion may provide advances in the powered-lift field.

The first section of the report describes the AbNET system, a hardware and software communications system designed for distribution automation (it can also find application in substation monitoring and control). The topology of the power system fixes the topology of the communications network, which can therefore be expected to include a larger number of branch points, tap points, and interconnections. These features make this communications network unlike any other. The network operating software has to solve the problem of communicating to all the nodes of a very complex network in as reliable a way as possible even if the network is damaged, and it has to do so with minimum transmission delays and at minimum cost. The design of the operating protocols is described within the framework of the seven-layer Open System Interconnection hierarchy of the International Standards Organization. Section 2 of the report describes the development and testing of a high voltage sensor based on an electro-optic polymer. The theory of operation is reviewed. Bulk fabrication of the polymer is discussed, as well as results of testing of the electro-optic coefficient of the material. Fabrication of a complete prototype sensor suitable for use in the range 1-20 kV is described. The electro-optic polymer is shown to be an important material for fiber optic sensing applications. Appendix A is theoretical support for this work. The third section of the report presents the application of an artificial neural network, Kohonen's self-organizing feature map, for the classification of power system states. This classifier maps vectors of an N-dimensional space to a 2-dimensional neural net in a nonlinear way preserving the topological order of the input vectors. These mappings are studied using a nonlinear power system model.

The feasibility of using Brayton power systems for nuclear electric spacecraft was investigated. The primary performance parameters of systems mass and radiator area were determined for systems from 100 to 1000 kW sub e. Mathematical models of all system components were used to determine masses and volumes. Two completely independent systems provide propulsion power so that no single-point failure can jeopardize a mission. The waste heat radiators utilize armored heat pipes to limit meteorite puncture. The armor thickness was statistically determined to achieve the required probability of survival. A 400 kW sub e reference system received primary attention as required by the contract. The components of this system were defined and a conceptual layout was developed with encouraging results. An arrangement with redundant Brayton power systems having a 1500 K (2240 F) turbine inlet temperature was shown to be compatible with the dimensions of the space shuttle orbiter payload bay.

The testing and evaluation of different bearing systems to be used in the turbine-alternator-compressor of a closed Brayton cycle electric power system are described. A specification of each bearing is presented along with the results of the evaluation and a comparison of the merits and limitations of each bearing. The contribution of improved bearings to the power supply reliability, potential life, and ability to accept shock and vibration is examined.

The testing and evaluation of different bearing systems to be used in the turbine-alternator-compressor of a closed Brayton cycle electric power system are described. A specification of each bearing is presented along with the results of the evaluation and a comparison of the merits and limitations of each bearing. The contribution of improved bearings to the power supply reliability, potential life, and ability to accept shock and vibration is examined.

This volume was digitized and made accessible online due to deterioration of the original print copy.

This volume was digitized and made accessible online due to deterioration of the original print copy.

This volume was digitized and made accessible online due to deterioration of the original print copy.

This item represents a case in PACER, the U.S. Government's website for federal case data. If you wish to see the entire case, please consult PACER directly.

http://uf.catalog.fcla.edu/uf.jsp?st=UF002388016&ix=pm&I=0&V=D&pm=1

Electric Machines and Power Systems 1984: Volume 9 , Issue Index. Digitized from IA1532430-05 . Previous issue: sim_electric-power-components-and-systems_1984_9_contents . Next issue: sim_electric-power-components-and-systems_january-february-1984_9_1 .

Electric Power Systems Research 1993: Volume 28 , Issue Index. Digitized from IA1652424-02 . Previous issue: sim_electric-power-systems-research_1993-08_27_3_0 . Next issue: sim_electric-power-systems-research_1993-10_28_1_0 .

Includes bibliographical references

This item represents an oral argument audio file as scraped from a U.S. Government website by Free Law Project.

As power levels of spacecraft rise to the 50 to 100 kW range, it becomes apparent that low voltage (28 V) dc power distribution and management systems will not operate efficiently at these higher power levels. The concept of transforming a solar array voltage at 150 V dc into a 1000 V ac distribution system operating at 20 kHz is examined. The transformation is accomplished with series-resonant inverter by using a rotary transformer to isolate the solar array from the spacecraft. The power can then be distributed in any desired method such as three phase delta to delta. The distribution voltage can be easily transformed to any desired load voltage and operating frequency. The reasons for the voltage limitations on the solar array due to plasma interactions and the many advantages of a high voltage, high frequency at distribution system are discussed.

Technological constraints, materials availability, production capacity, and manufacturing and installations plans and costs at different production levels are included in a study of concentrating collector industrialization. As cobalt for the engine and receiver is supply limited, alternative lower temperature alloys and higher temperature materials such as ceramics are discussed. Economics and production efficiency favor co-location of cellular and thin glass production for reflectors. Assembly and installation are expensive for small sites and few alternatives exist to apply mass production techniques to lower these costs for the selected design. Stepping motors in the size and quantities required are not commercially available today but could be in the future.

Technological constraints, materials availability, production capacity, and manufacturing and installations plans and costs at different production levels are included in a study of concentrating collector industrialization. As cobalt for the engine and receiver is supply limited, alternative lower temperature alloys and higher temperature materials such as ceramics are discussed. Economics and production efficiency favor co-location of cellular and thin glass production for reflectors. Assembly and installation are expensive for small sites and few alternatives exist to apply mass production techniques to lower these costs for the selected design. Stepping motors in the size and quantities required are not commercially available today but could be in the future.

Large increases in the complexity of shipboard electric loads as well as development of electric drive, integrated electric drive and pulsed power systems make manifest the present and future importance of naval electric power systems. The most crucial attribute of these systems is their ability to fulfill their function in the presence of \"large-signal\" perturbations. Fundamental differences between shipboard and commercial electric power systems make all but the most general nonlinear, \"large-signal\" stability analyses inappropriate for the design and assessment of naval electric power systems. The tightly coupled and compact nature of shipboard systems are best accommodated by composite system stability analyses. Composite system methods, based upon Lyapunov's direct method, require that each component's stability be represented by a Lyapunov function. A new Lyapunov function which is based upon coenergy is developed for 3-phase synchronous machines. This use of coenergy is generalizable to all electromechanical energy conversion devices. The coenergy-based Lyapunov function is implemented as a \"stability organ\" which generates waveforms at information teirninals of a \"device object\" in the object oriented simulation environment of WAVESIM. Single generator simulation results are used to acquire a measure of the \"over sufficiency\" of the coenergy-based Lyapunov function. Some means of combining the components' Lyapunov functions is necessary with composite system stability criterions. To provide the largest stability region in a Lyapunov function convective derivative space, thereby reducing \"over sufficiency\", a \"timevariant weighted-sum\" composite system criterion is developed. This criterion is implemented as a \"stability demon\" \"device object\" within the WAVESIM environment. The \"stability demon\" is tested through RLC circuit simulations and a two-generator simulation. The output of the \"stability demon\" is suitable for use within an overall system stabilising controller.

Large increases in the complexity of shipboard electric loads as well as development of electric drive, integrated electric drive and pulsed power systems make manifest the present and future importance of naval electric power systems. The most crucial attribute of these systems is their ability to fulfill their function in the presence of \"large-signal\" perturbations. Fundamental differences between shipboard and commercial electric power systems make all but the most general nonlinear, \"large-signal\" stability analyses inappropriate for the design and assessment of naval electric power systems. The tightly coupled and compact nature of shipboard systems are best accommodated by composite system stability analyses. Composite system methods, based upon Lyapunov's direct method, require that each component's stability be represented by a Lyapunov function. A new Lyapunov function which is based upon coenergy is developed for 3-phase synchronous machines. This use of coenergy is generalizable to all electromechanical energy conversion devices. The coenergy-based Lyapunov function is implemented as a \"stability organ\" which generates waveforms at information teirninals of a \"device object\" in the object oriented simulation environment of WAVESIM. Single generator simulation results are used to acquire a measure of the \"over sufficiency\" of the coenergy-based Lyapunov function. Some means of combining the components' Lyapunov functions is necessary with composite system stability criterions. To provide the largest stability region in a Lyapunov function convective derivative space, thereby reducing \"over sufficiency\", a \"timevariant weighted-sum\" composite system criterion is developed. This criterion is implemented as a \"stability demon\" \"device object\" within the WAVESIM environment. The \"stability demon\" is tested through RLC circuit simulations and a two-generator simulation. The output of the \"stability demon\" is suitable for use within an overall system stabilising controller.

Nine advanced energy conversion concepts using coal or coal-derived fuels are summarized. They are; (1) open-cycle gas turbines, (2) combined gas-steam turbine cycles, (3) closed-cycle gas turbines, (4) metal vapor Rankine topping, (5) open-cycle MHD; (6) closed-cycle MHD; (7) liquid-metal MHD; (8) advanced steam; and (9) fuel cell systems. The economics, natural resource requirements, and performance criteria for the nine concepts are discussed.

An overview of studies conducted to establish the requirements for advanced subsystem analytical tools is presented. Modifications are defined for updating current computer programs used to analyze environmental control, life support, and electric power supply systems so that consumables for future advanced spacecraft may be managed.

An overview of studies conducted to establish the requirements for advanced subsystem analytical tools is presented. Modifications are defined for updating current computer programs used to analyze environmental control, life support, and electric power supply systems so that consumables for future advanced spacecraft may be managed.

An overview of studies conducted to establish the requirements for advanced subsystem analytical tools is presented. Modifications are defined for updating current computer programs used to analyze environmental control, life support, and electric power supply systems so that consumables for future advanced spacecraft may be managed.

Electric Machines and Power Systems 1989: Volume 17 , Issue CONTENTS. Digitized from IA1532430-05 . Previous issue: sim_electric-power-components-and-systems_1989_16_6 . Next issue: sim_electric-power-components-and-systems_1989_17_index .

book

The size, eight, performance and thermal management of hybrid-electric power systems are limited by the performance of available silicon power devices. Potential improvements afforded by wide bandgap silicon carbide devices have been confirmed in Army programs, but the commercially available material severely limits performances. Superlattice silicon carbide material addresses the key limitations of this material; quality, size, cost, and incompatibility with silicon processing. Wide bandgap superlattice silicon carbide material has recently been grown on 4-inch diameter silicon substrates by NanoDynamics-88, Inc/C9 Corp.

Thesis advisor(s): Ashton, Robert W

Thesis advisor(s): Ashton, Robert W

Thesis advisor(s): Ashton, Robert W

A high-altitude nuclear detonation several hundred kilometers above the central United States will subject much of the nation to an electromagnetic pulse (EMP) consisting of intense steep-front short-duration transient electromagnetic fields followed by a geomagnetic disturbance with a duration of tens of seconds. Since 1983, the Department of Energy has been actively pursuing a research program to assess the potential impacts of one or more EMP events on the nation's electric energy supply. A nominal EMP environment suitable for assessing geographically large systems has been used to provide an indication of EMP impacts on electric power systems. It was found that a single high-altitude burst, which significantly disturbs the geomagnetic field, could cause significant load and generation loss, but permanent damage would be isolated. Multiple bursts would increase the disturbance. Nevertheless, based on the effects of a nominal EMP environment, a long-term black-out is not expected since major components such as power transformers are not likely to be damaged.

This invention provides a method and apparatus for determining a precise switching sequence for the power switching elements of electric power delivery systems of the on-off switching type and which enables extremely fast transient response, precise regulation and highly stable operation. The control utilizes the values of the power delivery system power handling network components, a desired output characteristic, a system timing parameter, and the externally imposed operating conditions to determine where steady state operations should be in order to yield desired output characteristics for the given system specifications. The actual state of the power delivery system is continuously monitored and compared to a state-space boundary which is derived from the desired equilibrium condition, and from the information obtained from this comparison, the system is moved to the desired equilibrium condition in one cycle of switching control. Since the controller continuously monitors the power delivery system's externally imposed operating conditions, a change in the conditions is immediately sensed and a new equilibrium condition is determined and achieved, again in a single cycle of switching control.

The activities of the Point-Focusing Thermal and Electric Applications (PETEA) project for the fiscal year 1979 are summarized. The main thrust of the PFTEA Project, the small community solar thermal power experiment, was completed. Concept definition studies included a small central receiver approach, a point-focusing distributed receiver system with central power generation, and a point-focusing distributed receiver concept with distributed power generation. The first experiment in the Isolated Application Series was initiated. Planning for the third engineering experiment series, which addresses the industrial market sector, was also initiated. In addition to the experiment-related activities, several contracts to industry were let and studies were conducted to explore the market potential for point-focusing distributed receiver (PFDR) systems. System analysis studies were completed that looked at PFDR technology relative to other small power system technology candidates for the utility market sector.

Electric Power Systems Research is an active peer-reviewed scientific journal currently published monthly by Elsevier. Launched in 1977, it publishes the latest research on the generation, transmission, distribution and utilization of electrical energy. Each issue features original articles and reviews on current advances in electric power systems for industrial, public, and home consumption, including power system planning and implementation, power system analysis and computation, electric energy production also from renewables, power systems operation, power system dynamic and transient performance, power systems protections, electric transportation systems, insulation coordination, power system economics, and power engineering education. Occasional special-focus issues are dedicated to a particular topic of interest or contain selected papers from relevant conferences and symposia.  The Internet Archive Collection contains microfilm published between 1984 and 1994.  Electric Power Systems Research is found online at: https://www.sciencedirect.com/journal/electric-power-systems-research Wikipedia: https://en.wikipedia.org/wiki/Electric_Power_Systems_Research The ISSN is 0378-7796

The handbook provides formulas and data for evaluating coupling of the high-altitude EMP to electric power systems and to facilities served with commercial electric power. The subjects covered include coupling to power transmission and distribution lines, transient coupling through transformers, lightning-arrester firing characteristics, and coupling through the service entrance. Grounding, EMP protective measures, and testing are also discussed. The emphasis of the handbook is on the EMP effects of concern to the power user, but much of the information contained in the handbook can also be used to evaluate the effects of the EMP on electric power systems.

Electric Power Systems Research 1993: Volume 27 , Issue Index. Digitized from IA1652424-02 . Previous issue: sim_electric-power-systems-research_1993-04_26_3_0 . Next issue: sim_electric-power-systems-research_1993-05_27_1_0 .

Electric Machines and Power Systems 1986: Volume 11 , Issue CONTENTS. Digitized from IA1532430-05 . Previous issue: sim_electric-power-components-and-systems_1986_11_index . Next issue: sim_electric-power-components-and-systems_1986_11_1 .

Electric Power Systems Research 1990 - 1991: Volume 20 , Issue Index. Digitized from IA1653329-06 . Previous issue: sim_electric-power-systems-research_1990-10_19_3 . Next issue: sim_electric-power-systems-research_1990-12_20_1 .

Electric Power Systems Research 1994: Volume 31 , Issue Index. Digitized from IA1652424-02 . Previous issue: sim_electric-power-systems-research_1994-09_30_3_0 . Next issue: sim_electric-power-systems-research_1994-10_31_1_0 .

Electric Power Systems Research 1994: Volume 31 , Issue Index. Digitized from IA1652424-02 . Previous issue: sim_electric-power-systems-research_1994-09_30_3_0 . Next issue: sim_electric-power-systems-research_1994-10_31_1_0 .

Book Source: Digital Library of India Item 2015.194250 dc.contributor.author: Satish Joshi dc.date.accessioned: 2015-07-08T04:11:43Z dc.date.available: 2015-07-08T04:11:43Z dc.date.digitalpublicationdate: 2005-08-27 dc.identifier.barcode: 1990010092500 dc.identifier.origpath: /rawdataupload/upload/0092/500 dc.identifier.copyno: 1 dc.identifier.uri: http://www.new.dli.ernet.in/handle/2015/194250 dc.description.scannerno: 14 dc.description.scanningcentre: IIIT, Allahabad dc.description.main: 1 dc.description.tagged: 0 dc.description.totalpages: 180 dc.format.mimetype: application/pdf dc.language.iso: English dc.publisher: Indian Institute Of Technology Kanpur dc.rights: Out_of_copyright dc.source.library: Indian Institute Of Technology Kanpur dc.subject.classification: Technology dc.subject.classification: Engineering. Technology In General dc.subject.classification: Mechanical Engineering In General. Nuclear Technology. Electrical Engineering. Machinery dc.title: Voltage Stability Amp Contingency Selection Studies In Electric Power Systems

A systems evaluation technique developed for the Systems Evaluation Division (Research) of DCPA is used in evaluating a specific local electric power system within the Louisiana-Southern Mississippi region. The model used in this evaluation is highly flexible and can be used for electric power systems of any magnitude from a local level to a national level. The general model concept employs the use of generation and demand nodes with transmission links, and includes an objective function which measures the response of a system to disruptions. Basically, the model is a constrained network flow model which is transformed into a modified transhipment linear programming format for analysis.

The concept of plug-in electric vehicles (PEV) are gaining increasing popularity in recent years, due to the growing societal awareness of reducing greenhouse gas (GHG) emissions, and gaining independence on foreign oil or petroleum. Large-scale deployment of PEVs currently faces many challenges. One particular concern is that the PEV charging can potentially cause significant impacts on the existing power distribution system, due to the increase in peak load. As such, this work tries to mitigate the impacts of PEV charging by proposing a decentralized smart PEV charging algorithm to minimize the distribution system load variance, so that a `flat' total load profile can be obtained. The charging algorithm is myopic, in that it controls the PEV charging processes in each time slot based entirely on the current power system states, without knowledge about future system dynamics. We provide theoretical guarantees on the asymptotic optimality of the proposed charging algorithm. Thus, compared to other forecast based smart charging approaches in the literature, the charging algorithm not only achieves optimality asymptotically in an on-line, and decentralized manner, but also is robust against various uncertainties in the power system, such as random PEV driving patterns and distributed generation (DG) with highly intermittent renewable energy sources.

This paper presents an information-theoretic approach to address the phasor measurement unit (PMU) placement problem in electric power systems. Different from the conventional 'topological observability' based approaches, this paper advocates a much more refined, information-theoretic criterion, namely the mutual information (MI) between the PMU measurements and the power system states. The proposed MI criterion can not only include the full system observability as a special case, but also can rigorously model the remaining uncertainties in the power system states with PMU measurements, so as to generate highly informative PMU configurations. Further, the MI criterion can facilitate robust PMU placement by explicitly modeling probabilistic PMU outages. We propose a greedy PMU placement algorithm, and show that it achieves an approximation ratio of (1-1/e) for any PMU placement budget. We further show that the performance is the best that one can achieve in practice, in the sense that it is NP-hard to achieve any approximation ratio beyond (1-1/e). Such performance guarantee makes the greedy algorithm very attractive in the practical scenario of multi-stage installations for utilities with limited budgets. Finally, simulation results demonstrate near-optimal performance of the proposed PMU placement algorithm.

The ongoing evolution of the electric power systems brings about the need to cope with increasingly complex interactions of technical components and relevant actors. In order to integrate a more comprehensive spectrum of different aspects into a probabilistic reliability assessment and to include time-dependent effects, this paper proposes an object-oriented hybrid approach combining agent-based modeling techniques with classical methods such as Monte Carlo simulation. Objects represent both technical components such as generators and transmission lines and non-technical components such as grid operators. The approach allows the calculation of conventional reliability indices and the estimation of blackout frequencies. Furthermore, the influence of the time needed to remove line overloads on the overall system reliability can be assessed. The applicability of the approach is demonstrated by performing simulations on the IEEE Reliability Test System 1996 and on a model of the Swiss high-voltage grid.

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Electric Machines and Power Systems 1989: Volume 16 , Issue Index. Digitized from IA1532430-05 . Previous issue: sim_electric-power-components-and-systems_1989_16_contents . Next issue: sim_electric-power-components-and-systems_1989_16_1 .

Electric Machines and Power Systems 1989: Volume 16 , Issue Index. Digitized from IA1532430-05 . Previous issue: sim_electric-power-components-and-systems_1989_16_contents . Next issue: sim_electric-power-components-and-systems_1989_16_1 .

The background, objectives and methodology used for the Small Power Systems Solar Electric Workshop are described, and a summary of the results and conclusions developed at the workshop regarding small solar thermal electric power systems is presented.

The background, objectives and methodology used for the Small Power Systems Solar Electric Workshop are described, and a summary of the results and conclusions developed at the workshop regarding small solar thermal electric power systems is presented.