Efficient, light-weight power conditioning equipment was investigated in the area of AC to AC transformation, where AC of a variable frequency is to be transformed efficiently into AC of a fixed frequency at a significant power level. This task, which fol...

... The primary benefits of a TACS or HTACS system for the Military ... basis for larger scale implementation of with solar powered tactical AC systems. ...

Sep 25, 2008 ... Kevin Boyce, HST Systems Engineer, ACS Repair: What failed is a power supply. And in fact, in the ACS there were two power supplies, ...

... The ac initiation system is pre-armed by ... activates a load when an ac power signal of ... Patents, *Explosives initiators, Control systems, Ignition circuits ...

power over extremely long distances, but to also connect to AC asynchronous grid systems, i.e., AC systems operating at different frequencies. ...

... The four technical architectures are: Medium Volt AC Power Generation (MVAC), High Frequency AC Power Generation (HFAC), Medium Voltage ...

Power quality in AC power system depends on the harmonic content of the waveform . To accurately predict the content of harmonic components in a particular ...

... Accession Number : AD0727748. Title : AC Power System Evaluation Variable Frequency Input - Constant Frequency Output. ...

The system described provides protection for phase sensitive loads from being or remaining connected to ac power lines whenever a phase reversal occurs. It comprises a solid state phase detection circuit, a dc power relay circuit, an ac-to-dc converter fo...

A harmonic power flow program applicable to space power systems with sources of harmonic distortion is described. The algorithm is a modification of the Electric Power Research Institute's HARMFLO program which assumes a three phase, balanced, AC system w...

... DTIC Online - This search queries the DTIC ... the feasibility of power extraction optimization. ... CIRCUITS, AIRCRAFT ENGINES, ELECTRIC POWER ...

This patent describes an energy management circuit comprising: a laser; an AC input with a maximum power level; a DC source of energy operating in conjunction with the AC input and functioning to provide supplementary power as needed for operation of the laser, when the system ...

This conference examined the following aspects of 750 to 1500 kV ac power transmission systems and equipment: trends in systems and equipment development; electric field measurements and the consideration of electric fields in EHV and UHV ac system design...

This patent describes a two-phase AC power supply. It comprises AC systems; connectors; electric currents; and phase shift.

Feb 1, 1999 ... Basically, an UPS system converts some or all of the AC power into DC for the battery and then back into AC power for the load. ...

An alternating current power generation system adopted to inject power in an already powered power line is discussed. The power generating system solves to adjustably coup an induction motor, as a generator, to an ac ...

As more dc terminals, in the form of links or multiterminal systems, come into operation, the opportunity for controlling ac line flows using the injected dc powers increases. This paper describes a study undertaken to determine the feasibility of using an on-line method to coordinate the dc injections of a multiterminal dc ...

This report reviews a number of issues specific to stand-alone AC lighting systems. A review of AC lighting technology is presented, which discusses the advantages and disadvantages of various lamps. The best lamps for small lighting systems are compact f...

Other commercial and defense applications include pulse power conditioning for high power electronics and high voltage AC systems. ...

... Page 3. POWER SYSTEM PRINCIPLES Electric power is transmitted from generator to load primarily by alternating current (AC) systems. ...

active and reactive power, and spinning reserves in order to maximize profits. Results for a 14-node system are also presented. Index Terms�Ac system, ...

needs in both the 115 V ac and 28 V dc systems and excess power will be made ... Both the ac and dc systems use the aircraft structure for ground. ...

Contents: Power Loading Data; Power Loading for the Microwave Landing System (MLS); AC Power Loading for MLS Equipment; DC Power Loading for MLS Equipment; AC Electrical Power; DC Electrical Power; ...

Apparatus for conditioning power generated by an energy source includes an inverter for converting a DC input voltage from the energy source to a square wave AC output voltage, and a converter for converting the AC output voltage from the inverter to a sine wave AC output voltage.

This paper contains an evaluation of the onsite ac power system reliability. The approach to determine the onsite system reliability is to gather from the operating nuclear plants detailed data that have not been available to the NRC, to select typical bu...

The results of a study for the improvement of Spacelab's baseline electrical power and distribution system (EPDS) are presented. Three technical areas are covered. These are improvement of baseline-EPDS hardware, the introduction of an additional power source for experiment power augmentation, and the replacement ...

Success and failure data of test and emergency starts of emergency ac power sources (diesel generators) at US nuclear power plants were collected and evaluated to estimate diesel generator reliability parameters. A regression analysis of the estimates of ...

Thyristor drives with their nonsinusoidal currents and momentary commutation shorts are becoming more prevalent on ac power systems. The effects of ac power line inductance on line pollution and successful operation of the drive and common drives on the same feeder will be evaluated.

The electric power distribution systems for spacecraft are compared concentrating on two interrelated issues: the choice between dc and high frequency ac, and the converter/inverter topology to be used at the power source. The relative merits of dc and ac...

Concepts of maximum power transfer of dc systems and associated ac voltage variations, particularly at inverter stations having low short-circuit ratios, have been extended to include various ac load models and an ac line in parallel with the dc line. The operating capabilities are shown to ...

This paper contains an evaluation of the onsite ac power system reliability. The approach to determine the onsite system reliability is to gather from the operating nuclear plants detailed data that have not been available to the NRC, to select typical but detailed design features, and to combine the two to ...

This program introduces the technician to three phase a-c power and its relationship to rectifier power conversion systems. A brief introduction is given as to the engineering significance of various parameters such as, phase rotation, ac power relationsh...

Jan 2, 2008 ... The PSF offers the capability for testing of flywheel systems and components, battery systems, fuel cells, AC power sources, ...

The optimum generation of electricity from wind power requires that the load (the generator) be matched to the power source (the wind). Some specialists feel that the optimum wind power system will be built around the synchronous ac generators. The advantages, disadvantages, and optimum ...

The objective of the study is to estimate the probability of failure of the battery system of a nuclear power plant due to loss of ventilation in the battery room during AC blackout. This is part of the more general problem of the interaction between non-...

The power quality on the transmission lines is less of a concern with an AC system. At the point of use (power distribution) we will need to use Delta to ...

dc to ac conversion techniques, line-commutated inverters, self-commutated inverters, utility interconnection, and the application of dc to ac conversion to photovoltaic systems are discussed. (WHK)

The reader is informed of what was done for the mathematical modeling of the dc-ac inverter for the Space Shuttle. The mathematical modeling of the dc-ac inverter is an essential element in the modeling of the electrical power distribution system of the S...

dc to ac conversion techniques, line-commutated inverters, self-commutated inverters, utility interconnection, and the application of dc to ac conversion to photovoltaic systems are discussed. (ERA citation 04:046081)

The ubiquitous power-law frequency dependence observed for the ac conductivity in highly disordered semiconductors has a number of competing explanations. We review these mechanisms and discuss their relation to a simple Langevin theory for conductivity in confined regions. The theory is used to interpret recent measurements of the ac ...

By making use of the power flow control of dc system, the disturbance in a paralleling ac system may be removed without delay. The control system developed is used to prevent the generator from falling out of step. It was clear that the control system was adoptable for the ...

Modulation of power transmitted over a proposed multiterminal dc system to provide effective stability enhancement of a large ac system in the Southwestern U.S. is demonstrated in this paper. This proposed multiterminal dc system connecting the Phoenix, Mead and Los Angeles areas could be in ...

for geared system, pm or synchronous for DD. Generator-side converter converts AC electric power to DC Line-side converter converts DC to system-frequency AC (50 Hz or 60...

In order to find exactly the permitted difference limits of phase, frequency and magnitude of voltage between both power systems in cases where a separated power system was reparalleled to a trunk transmission line, fundamental experiments were carried ou...

power conditioning systems. They have a low dissipation factor along with good stability and a potential temperature capability of ...

The Patent Application Discloses an electrical power conversion system designed to operate on three-phase AC voltage generated by a motor generator, a modification is provided to permit the use of a DC power source to operate same. The power conversion sy...

An AC uninterruptible power source is disclosed that provides multiphase power output signals for actual use and a selectable single phase power output signal for use in testing. The AC uninterruptible power source further comprises at least one battery. The single phase ...

This is volume 2 of the proceedings of the IEEE International Conference on Power Electronics, Drives and Energy Systems for Industrial Growth held during January 1996, in New Delhi, India. The topics of this volume include AC/DC and AC/AC converters, induction generators, traction and electric vehicle drives, ...

This paper describes the design, development, and performance results of a large-area photovoltaic module whose electrical output is ac power suitable for direct connection to the utility grid. The large-area ac PV module features a dedicated, integrally mounted, high-efficiency dc-to-ac power ...

In present rapid cycling synchrotron magnets ac and dc currents flow in the same coil to give the desired field. The circuit reactance is made zero at dc and the operating frequency by running the magnet in series with an external parallel resonant LC current. We propose to return the ac flux in a gap next to the synchrotron. The dc coil encloses the ...

Emergency onsite ac power systems at nuclear power plants are a major concern in plant risk assessments because of the relatively large frequency of loss of offsite power and the dependence of most other safety systems on ac power. ...

A handbook detailing how to changeover to AC electrical power, DC/DC and mechanical drilling rigs is presented. Electrical power generation and control is discussed, along with operating AC systems efficiently and economically. A chapter on electrical technology advances is also presented. ...

A Telecom power supply is studied and analyzed from control system viewpoint. It consists of three stages: AC/DC rectifier, a backup battery, and a Telecom load. The AC/DC rectifier stage can be composed of paralleled DC/DC converters preceded by parallel...

A Telecom power supply is studied and analyzed from control system viewpoint. It consists of three stages: AC/DC rectifier, a backup battery, and a Telecom load. The AC/DC rectifier stage can be composed of paralleled DC/DC converters preceded by parallel...

This paper describes the development of ac and dc interface specifications and array voltage trade-off studies leading to a conceptual design of a central station rated (1 to 10 MW) photovoltaic power conversion system (PCS). The ac interface specificatio...

A phase protection system is provided for protecting phase-sensitive loads from being or remaining connected to ac power lines whenever a phase reversal occurs. It comprises a solid state phase detection circuit, a dc power relay circuit, an ac-to-dc conv...

This report contains a work statement for a study in which the objective is to examine the dynamic relationships of integrated ac/dc power systems containing high voltage direct current circuit breakers; a one-page discussion of the effects of a planned HVDC system on interconnected ac ...

Line-commutated inverter (LCI) power conditioning systems are applied in photovoltaics (PV) applications as a dc to ac energy conversion system. The inverter accepts dc power from the photovoltaic array in a manner that is compatible with array design characteristics. The dc ...

A superconducting magnetic energy storage coil connected in parallel between converters of two or more ac power systems provides load leveling and stability improvement to any or all of the ac systems. Control is provided to direct the charging and independently the discharging of the ...

Contents: The national power grid study - an introduction; U.S. electric power grid concepts - the existing system and proposed concepts for improvements to bulk power supply; Issues facing the electric power industry - the environment for proposals to ac...

... Army supply system. Detailed technical descriptions of six power supply models comprising the standard family are given. ...

are heavy). An ac powered system will not be limited by a charging duty cycle, which will allow longer rover tests. Simulator Buildup. The simulator power supply ...

Mar 1, 2011 ... Such phenomena were also not anticipated when power quality was specified for either 270 vdc or 400 Hertz ac power systems. ...

... of an electric power system that displays three-phase ... induction, regenerates AC power from one circuit into ... single load and generator, respectively. ...

... are synchronized to the 60 Hz line frequency and contain some type of back up oscillator to insure continued operation during AC power outages. ...

A system is described for power conditioning a line of supply of AC power from an AC source to an AC load, comprising: a first array of static power switches mounted across one AC source and AC load; a second ...

A ground fault detection and shutoff system for underwater power transmission provides protection to divers from swimming into electric fields. This system uses DC power to monitor the true resistance of the load system rather than the AC power to the ...

The wayside power system provides all the power requirements of an electric vehicle operating on a fixed guideway. For a given set of specifications there are numerous wayside power supply configurations which will be satisfactory from a technical standpo...

This paper investigates the impact of an inverter station on the torsional dynamics of a turbine-generator set which is located at the rectifier side of a parallel HVdc-ac power system. The studies show that depending on the stiffness of the inverter ac bus and electrical coupling between the inverter and rectifier ...

Sep 3, 2010 ... SUBTOPIC TITLE: Power Management and Storage. PROPOSAL TITLE: Efficient Lightweight AC-AC Power Control for Solar UAV ...

The technical and economic assessment of AC and DC transmission systems; long distance transmission, cable transmission, system inter-connection, voltage support, reactive compensation, stabilisation of systems; parallel operation of DC links with AC systems; comparison ...

The fast development of power electronics based on new and powerful semiconductor devices has led to innovative technologies, such as high voltage dc transmission (HVDC) and flexible ac transmission system (FACTS), which can be applied in transmission and distribution systems. The technical and ...

As ac/dc systems become further integrated, multiple-infeed converter (MIC) systems can be expected to become more common. In this paper, different categories of MIC systems are defined, and the impact of the ac system strength and the coordination of reactive ...

A mathematical model is developed to investigate the dynamic stability dc system in parallel with an ac transmission system. The dynamic stability model for a one machine infinite bus system is developed first. This model is used to determine the dynamic stability of the parallel ac - dc ...

more viable on long duration missions. Power Distribution. System designs were also explored. High and low voltage. DC systems were compared with AC systems ...

The assimilation of large numbers of large wind turbine generators into utility grids posses significant operational questions. This paper explores design and operational issues associated with the interconnection of wind farms using a controllable AC/DC/AC series-connected interface. The study is in terms of steady-state operation of and transient effects on both the ...

@vos.nagaokaut.ac.jp URL: pelab.nagaokaut.ac.jp/ Abstract -- This paper proposes a maximum-power-point tracking (MPPT as a maximum-power-point tracking (MPPT) method, which makes it possible to acquire as much power as possible point on the power vs. voltage (or current) ...

Multiterminal dc system offers operational advantages in network reactive power flow control. The var control capabilities of the dc system is of particular interest in this thesis. This thesis presents a formulation for coordinating multiterminal dc syst...

The 30-MJ superconducting magnetic-energy-storage (SMES) system was devised as an alternate means to modulate the Bonneville Power Administration (BPA) Pacific AC Intertie, a part of the Western US Power System, to prevent undamped power oscillations at 0...

Between 2000 and 2003 Transportable AC Systems (TACS) and Hybrids (HTACS) were developed and demonstrated to support the electrical requirements of Command Centers in the field. Primary power was provided by unbreakable, lightweight, flexible solar module...

The successful application of two terminal dc links suggests that even greater flexibility in power dispatch and enhancement in stability can be realized by a multiterminal dc (MTDC) system embedded in an interconnected ac grid. Several utilities are look...

The hvdc system provides an effective means to improve the stability of the ac power system and to control the power system. However, if the hvdc system is connected to a weak ac system, the voltage at the ...

Conventional ac-dc converters present two important disadvantages: they create harmonic currents and require reactive power. To reduce these drawbacks, a diode rectifier is directly connected in series with a chopper controlled by pulsewidth modulation. Both are preceded by a series inductance (added to the equivalent one of the power ...

An analogue computer study was made using real power representation. The design of the necessary control for such a dc link brings out implications not only for an isolated turbine but also for any small power system connected to a large dc link where the power flow in the dc link can contribute to the dynamic ...

the generator angle and the DC power Pdc under the case 1 fault; and Figs. 6 and 7 show the system dynamic to be Pd dc � 0:4 in order to minimize the change of DC line power and to keep the pre-fault generatorA nonlinear robust HVDC control for a parallel AC/DC power ...

Line-Commutated Inverter (LCI) technology provides reliable, efficient and cost-effective DC to AC power conversion for photovoltaic systems. Its only potential shortcoming for large scale use was power quality. In 1980 MIT Lincoln Laboratories and Windworks, Inc. recognized the need for power ...

Direct AC/AC converters have been studied due to their potential use in power converters with no DC-link capacitor, which can contribute to the miniaturization of power converters. However, the absence of a DC-link capacitor makes it difficult to control the AC motor during power interruption. ...

Development of techniques and analytical tools for utilizing the inherent controllability of multiterminal hvdc transmission to enhance the performance of an integrated ac/dc power system were explored. Specific investigations that were performed during the course of the project were described, including steady state operation of ...

Results achieved by the intermediate power level ac-dc model in Philadelphia demonstrate the unusual features and advantages of this research tool for working toward accomplishment of over-all aims of the project. Insofar as can be determined, it is presently the only facility capable of evaluating the dynamic interactions between ...

This working group report presents dc benchmark models tailored to ac/dc interaction. This is to encourage comparisons of the performance of different control strategies or computational tools related to various ac/dc interaction phenomena and system dynamic performance. System data and results are available on ...

The possibility of abnormal harmonic generation in an ac system feeding a converter load is examined from the standpoint of automatic control systems used in modern hvdc transmission systems. It is shown that with certain types of automatic controls, the firing angles of converter valves may sustain some errors, ...

This was a summary report of aircraft power capacity, both primary & secondary systems, because the power requirements of future special weapons relied on the power source change (from alternating current to direct current) in aircraft design philosophy.

The reliability of the emergency ac-power systems typical of several nuclear power plants was estimated, the costs of several possible improvements was estimated. Fault trees were constructed based on a detailed design review of the emergency ac-power systems of 18 nuclear plants. The failure ...

The SERT 2 spacecraft utilizes a 1.5-kW solar array as the primary source of electrical power. The spacecraft power system controls this power as required for housekeeping functions, experiments, and ion thruster system. To meet mission objectives, three separate systems ...

Systems simulations are presented for the regulated bus concept, for the ac distribution system, and for the Maximum Power Point Tracking (MPPT) distribution system. Results show that the regulated bus system performs relatively well both for continuous and discontinuous ...

was remember the soldier, it must be set and forget. The systems can operate on a wide range of power sources; AC inputs from 60 to 400 Hz and DC inputs of ...

...A phacofragmentation system is an AC-powered device with a fragmenting needle intended for use in cataract surgery to disrupt a cataract with ultrasound and extract the cataract. (b) Classification. Class...

The identification of hardware developments and system applications which exemplify cost and operational advantages of integrated ac/dc power systems is discussed. The three principal tasks undertaken were: assessment of equipment developments; quantification of operational advantages; and interaction with ...

A new quasi current resonant dc link (QCRDCL) topology has been developed in this paper. Although prototype current resonant dc link topologies for ac/ac power conversion have had such problems as irregular high current peaks, uncontrollable pulse width, etc., this new topology enables the ac/ac conversion system ...

A photovoltaic power generation system based on immittance conversion theory is described. The name of an AC module stands for an integrated inverter installed on the backside of the PV module panel, and it generates about 100W of ac power. One distinctive feature of the proposed ...

This paper discusses results of an EPRI contract on control design for an ac/dc transmission system to increase power transfers limited by dynamic stability. The control is achieved by modulating the rectifier dc current or power and the inverter dc voltage. Coordinated active and reactive ...

This paper presents the preliminary design of poloidal field power supply system of HT-7U super-conducting tokamak. With an emphasis on AC/DC power converter, DC circuit breaker, quench protection, harmonic suppression and static var. compensation, and AC power ...

Components of the system were built and tested based on payloads containing tansistor power amplifiers (TPA) and traveling wave tubes (TWT). A dc/ac square wave inverter supplying two TPA power supplies, an electronic power conditioner for a 150 W TWT, an...

In a study conducted by the General Electric Company for EPRI, the power modulation of a high-voltage direct-current (HVDC) system for stabilization of an ac/dc network was investigated. The use of both active and reactive power modulation (as opposed to ...

Solid state remote power controllers (RPC's) are now available to control and protect all types of loads in both ac and dc power distribution systems. RPC's possess many outstanding qualities that make them attractive for most system applications. A revie...

This note describes a 75KVA quiet power distribution system for X 653 in neutrino Lab D. It is fed from the regular AC distribution which exists in the building and it has no standby power. Its purpose is to remove electrical disturbances which are presen...

This invention relates to a power supply system having the capability of furnishing to a load sensitive to electrical faults and interruptions, electrical power for prolonged periods of time after a utility or other external power supply source thereto is interrupted. The system comprises a ...

The need for the system harmonic impedance information and methods to determine it by test and/or calculation is addressed. The project undertook research to measure harmonic impedances and sources on a power system and to modify existing analytical techniques to more closely match the field test measurements. The information will ...

Optimal Modulation Controllers for multiarea ac/dc systems are designed by a recursive algorithm that determines the state weighting matrix Q of a linear quadratic performance criterion. The basic feature of the proposed method is the reduction of the number of iterations as well as minimization of the calculations involved. This method is applied for ...

This paper reviews historical trends of electric power system simulation technology focusing on the method of symmetrical coordinates and ac network analyzer. The method of symmetrical coordinates was proposed by C. L. Fortescue in 1918. The method of symmetrical coordinates was refined from the original usage and became very easy ...

Automatic power servicing and control was investigated. Suitable approaches for accomplishing power system optimization through fault detection and system reorganization are presented for two typical systems. A three-phase DC-AC Bridge Chopper Inverter wa...

In a utility-interactive photovoltaic system, the electrical characteristics of the dc-to-ac power-conditioning unit (inverter) influence the quantity of electrical energy delivered by the system, and therefore, affect the user worth of the system. An ana...

This report discusses the integration of three AC powered cars into the Cleveland Transit System's revenue operation during 1973. The year of operation was divided into two distinct operating periods. In the first period, January through June, the three A...

A magnetic demagnetizing device consists of a transformer tapping an a-c line connected by an electronic system that effects and regulates a-c power flow to an exit transformer, the secondary of which is coupled to the demagnetizing coil. (D.C.W.)

An ac motor controller for an induction motor electric vehicle drive system was designed, fabricated, tested, evaluated, and cost analyzed. A vehicle performance analysis was done to establish the vehicle tractive effort-speed requirements. These requirem...

The purpose of the study reported here was to examine generic cost differences between direct current (dc) and alternating current (ac) systems and to identify situations in which dc is clearly advantageous for long distance and bulk power transport. The ...

This patent describes an internal combustion engine electrical system comprising: an A.C. generator driven by an internal combustion engine; a rectifier circuit for rectifying A.C. output generated by the A.C. generator; a constant voltage power circuit which outputs a substantially constant ...

A control strategy for an AC/DC/AC interface to smooth or limit wind farm output is investigated. The need to follow rapid power variation from uncontrolled wind farms with expensive gas turbines limits the amount of penetration of wind energy systems in existing utilities. An AC/DC/AC interface makes it possible ...

In this paper, a short introduction in design considerations of FLATCON� CPV module and field data of the system technology over up to two years are presented as well as field experiences with the operation of the systems. FLATCON� modules are based on III-V triple junction cells, a Fresnel lens array, and a glass cover and bottom plate. In 2008, ...

A system and method for detecting partial discharges or arcing in wiring or cables is disclosed. The system employs a high-voltage AC power source to generate a high-voltage, low-current AC waveform, which is propagated through a selected wire, which in t...

This paper presents some studies of ac voltage behavior of the poloidal field power supply system for JT-60 using computer simulations. The system consists of a motor-generator (MG), several thyristor convertors, two sets of dc circuit breakers and some other devices. Two analyses are made with respect to the ...

In the past few years, many papers have been published on state estimation applied to electric power systems. Different types of algorithms - static, tracking and dynamic-have been proposed aside with a variety of applications: detection and identification of bad data, network configurator, etc. Most of such studies have been carried out for ...

The use of microprocessors in power converter controls is of interest since they could reduce system costs, increase system adaptability, and enhance system reliability where analog circuitry is conventionally used. This paper discusses the techniques that were applied in designing a complete ...

Techniques for energy conservation of reducing losses in ac motor driven systems were compared. The impact on electric utility system as a harmonics, power factor of operation, and Electro Magnetic Interference (EMI) is considered. The techniques evaluated are: (1) the NASA Power Factor ...

This paper presents and discusses techniques for energy conservation by reducing losses in ac motor driven systems, proposed by the technical community in response to surging cost of energy. An important aspect considered is the impact on electric utility systems in terms of harmonics and power factor of operation. ...

Station blackout is the complete loss of alternating current (ac) electric power to the essential and nonessential buses in a nuclear power plant; it results when both offsite power and the onsite emergency ac power systems are unavailable. Because many ...