Showing papers on "Electric power published in 1982"

Vibration sensor and electrical power shut off device

Abstract: A vibration sensor and electrical power shut off device including a pendulum switch constructed for universal movement whereby vibration in any direction causes the pendulum switch to close and actuate a solenoid that shuts off electrical power at a switch point in an electrical power line, a low voltage circuit remaining energized to indicate power interruption.

Eigenvalue Analysis of Synchronizing Power Flow Oscillations in Large Electric Power Systems

Abstract: A new computer program is described which permits eigenvalue analysis of the oscillations associated with synchronizing power flow in large electric power systems. The program has been given the acronym AESOPS, for the Analysis of Essentially Spontaneous Oscillations in Power Systems. The program is the principal product of a research project funded by the Electric Power Research Institute. This project was recommended by the Westinghouse Advanced Systems Technology Division and the MAPP/MARCA Dynamic Device Operating Task Force.

Electricity Pricing: Theory and Case Studies

Abstract: The rapidly increasing cost of electric power in recent years has brought about a growing awareness of the importance of pricing policies in maximizing the net economic benefits of consumption and avoiding waste. Although the theoretical principles governing optimal pricing strategies have long been understood, their practical application to the energy sector in general, and to electric power in particular, has not been seriously pursued until recently. Increasing unit costs, however, have provided the stimulus for a change in approach, and there is now a good deal of evidence that marginal cost pricing is becoming accepted as an important criterion that should be considered in determining electric power tariffs. The book contains a summary of the economic principles underlying marginal cost pricing for electric power, and emphasizes the importance of the adjustments that need to be made to the strict long-run marginal costs (LRMC) to reflect the various economic, social, and engineering objectives and constraints that are actually faced by policymakers in the energy sector. The book also consists of case studies that follow a two-stage procedure in which the LRMC of electric power is used to weigh the costs and benefits of other policy objectives that might be addressed through the medium of power pricing. LRMC is therefore treated largely as a benchmark by which other economic and social objectives may be consciously judged.

Dimmable electronic gas discharge lamp ballast

Abstract: A two-wire electronic dimming ballast arrangement for one or more gas discharge lamps is disclosed which includes an inverter driven by a variable pulse width electric power and a control system for modulating the pulse width of the variable pulse width square wave electric power driving the inverter A unique distortion suppression system is provided for suppressing current abberations and achieving substantially a unity power factor

Electrostatically operated dust collector

Abstract: An improved electrostatically operated dust collector is disclosed which includes a high voltage power supply circuit by way of which a direct current having high voltage fed from a commercial power supply network is applied thereto and a control circuit for controlling said high voltage power supply circuit. The improvement consists in that the dust collector further includes an intermittently operative electric power feed circuit in which feeding of DC electric power thereto is effected for a period of time T 1 , then feeding of electric power is intermitted for a period of time T 2 . The aforesaid steps are repeated. A preset circuit also forms part of the improvement in which circuit the aforesaid feeding time T 1 and no-feeding time T 2 are preset to a required value respectively. An intended energy saving is ensured by the improvement.

Rationing Energy to Industries: Priorities and Input-Output Dependence

Abstract: A short time ago it was unthinkable and deemed an academic exercise to speak of rationing. People thought that there could be no crippling energy crisis because our energy czars and planners would presumably take our needs into their projections. Today the situation looks very different. Witness the lack of natural gas in the cold winter of 1976–77, which caused the shutdown of some schools and industries, and the coal strike of 1977–78. Lack of coal caused a shortage of electric power in the Midwest, and electric power companies planned to ask for an end to all outdoor lighting and evening sports events plus a cutback of retail business schedules. The companies were also prepared to slice industrial electric usage to between 50 percent and “maintenance level,” forcing the shutdown of many factories.

An Analysis of Electric Power Brokerage Systems

Abstract: The purpose of electric power brokerage systems, such as the one established in Florida, is to reduce the aggregate cost of generating electricity by making short-term transfers of electric power between utilities (economy energy exchanges). However, the methods currently used to determine the buyers and sellers, and the quantities exchanged, can be improved to increase the savings. Two new algorithms are presented that result in greater savings to the utilities--a network flow algorithm applicable to the Florida system, and a more general algorithm using a version of dynamic programming. The effects of several methods of dividing the savings among the utilities are discussed. Finally, some initial ideas are presented on how an energy broker can be extended to longer time periods.

138-kV, Six-Phase Transmission System: Fault Analysis

Abstract: In the past decade, transmission planners and researchers have been keenly investigating the feasibility of six-phase concept as a planning alternative. The concept, if proved feasible, would alleviate the problem of acquiring additional rights-of-way to meet the increase in electric power and energy demand. Allegheny Power System (APS) has been investigating the conversion of some of their 138-kV three-phase double- circuit lines to 138-kV six-phase lines. The latter is an alternate option to 230-kV three-phase upgrading of the line.

Controller for alternating current elevator

Abstract: An apparatus for controlling an AC powered elevator by rectifying a commercial AC power source into a direct current through a rectifier, converting the direct current into a variable frequency AC power through a main inverter, driving the AC motor by the thus converted AC power to operate the cage of the elevator, and sending the regenerated electric power back to the commercial AC power source via a regeneration inverter connected to the DC side of the main inverter when regeneration braking is applied to the electric motor. If the main inverter becomes defective, the main inverter is separated from the electric motor, the AC side of the regeneration inverter is connected to the motor, and the motor is operated by relying upon the regeneration inverter.

The Effects of Reduced Voltages on the Efficiency of Electric Loads

Abstract: The paper reports the results from Phase I of Electric Power Research Institute RP1419 and describes the efficiency of important power system loads as a function of voltage. A wide variety of loads have been tested at seven input voltages ranging 100/200 to 126/252 volts, and a methodology has been developed to estimate distribution system efficiency as it relates to the operating level of voltage.

Exit sign lamp flashing system with self-checking provisions

Abstract: An emergency exit sign auxiliary lamp flashing system operates from self-contained rechargeable batteries upon failure of the electrical power from the AC power mains supplying power to the exit sign, including a charging circuit for recharging the batteries, with provisions for preventing overcharging and for disconnecting the load from the batteries before the battery voltage drops to a level which would impair its service life. Included is a solid state circuit which provides for automatically exercising and self-testing the proper functioning of the system to ensure its being serviceable when called upon to function during a power failure by periodically simulating the effect of a failure of AC power and verifying that the battery, lamp and flashing circuit operate normally or signalling a visual and/or audible alarm if they fail to operate properly.

Power/energy: Homeostatic control for electric power usage: A new scheme for putting the customer in the control loop would exploit microprocessors to deliver energy more efficiently

Abstract: Presents a new scheme for putting the customer in the control loop that would exploit microprocessors to deliver energy more efficiently. A homeostatic control scheme (homeostasis denotes a biological balance of separate functions in an organism) calls for continual updating of electrical rates, based on supply and demand, and continual communication of those rates to customers by the electric utility. Drawing heavily on today's load-management practices while greatly expanding the scope and nature of utility-customer interactions, homeostatic control would establish a marketplace for electric energy.

Cooling and power input assembly

Abstract: A cooling and electrical control assembly is provided for an electrical equipment such as a computer which is normally provided with venting slots for the dissipation of heat by the normal flow of ambient air. The ventilation slots on certain computers, such as an Apple Computer, are located on the upper sides of the housing for the computer, with the slots extending into the top panel of the electrical equipment and also down the sides thereof. The cooling and electrical control assembly disclosed in the present specification includes a housing having an open side, and protruding fingers for engaging the ventilation slots of the electrical equipment and for holding the housing into engagement with the side and top of the electrical equipment with the open side of the housing in sealing engagement with the ventilation openings. A fan is provided in the housing to exhaust air from the electrical equipment through the ventilation slots. An electrical switch and electrical power connections are provided so that the fan is turned on, and power supplied to the main electrical equipment when the switch is actuated. The housing may be merely set in place with the fingers extending down into the ventilation slots, and the weight of the housing holding it against the electrical equipment, so that no screws or other fasteners are required for installation.

Power supply system for heat and electricity

Abstract: A power supply system for generating at least one of heat and electricity which includes a number of statically and functionally independent units adapted to generate at least one of heat and electricity which enable a maximum utilization of primary energy. For decentralized power supply over short and low loss supply lines the individual units are constructed as stackable modules. By exchanging or adding one or more modules, it is possible to adapt the flexibility of the power supply system to changes in demand for the energy thereby providing a practical approach to the utilization of waste heat for energy conservation purposes.

Feasibility Sets for Steady-State Loads in Electric Power Networks

Abstract: Using mathematical programming duality, explicit conditions are found which characterize the set of substation loads that can be served with the available generation resources without overloading the transmission lines or transformers. This feasibility set is a convex polyhedron in the space of substation load vectors, when the distribution of power flow through the network is represented either by the DC load flow or the transportation flow model. The impact on the feasibility set of changes in the generation and transmission system is analyzed. This analysis is then used to construct a probabilistic supply reliability measure.

X-inefficiency and interfirm rivalry: evidence from the electric utility industry

Abstract: Competition from the natural gas industry is shown to increase the efficiency of the work force of electric power utilities. This conclusion is qualified to the extent that duopoly rivalry does not represent perfect competition in a free market. As natural gas reserves decline, however, the impetus to improve efficiency will diminish, but this will be offset by technological advances in both power generation and power transmission. If regulators develop policies to encourage competitive interplay, utility performance is more likely to improve. 38 references, 3 tables. (DCK)

The persistent PCB problem.

Abstract: The Electric Power Research Institute's $7 million, five-year research program to find a way to manage PCB pollution is discussed. PCBs are used in two types of sealed electric equipment: 1) transformers that raise or lower the voltage of a power line; and 2) capacitors on utility poles that help maintain constant voltage in homes. PCB spills and methods of detection and extraction are discussed, along with the Environmental Protection Agency's attempts to regulate PCB use. (JMT)

Control device for hot-water reserving type electric water heater

Abstract: PURPOSE:To reduce heat dissipating loss and improve power transmission efficiency by a method wherein the necessary conducting time of electric power supplied to a heating body is operated by detecting feed water temperature and the amount of heat of the hot-water remaining in a hot-water reserving tank and the necessary conducting time is contrived so as to be completed at a time when the conduction of midnight electric power is finished. CONSTITUTION:The temperature of water fed into the hot-water reserving tank is detected by a feed water temperature sensor 6 while the amount of heat to be reserved is operated in an operator 7 from the detected value of the sensor 6 and the capacity of the hot-water reserving tank. The amount of heat of the hot-water remaining in the hot-water reserving tank is detected by the detecting unit 8 for the amount of heat of the remaining hot-water while the necessary conducting time is operated in the operator 9 from a difference between the amounts of heat detected by the operator 7 and the unit 8. The conduction of electric power supplied to the heating body 2 is controlled in a timer unit 10 so that the necessary conducting time, obtained by the operator 9, has been completed at the time when the supply of the midnight electric power is finished. The high-temperature hot-water, raised in the temperature thereof, will not be left for a long period of time and the heat dissipating loss may be reduced. Further, the electric power is supplied in the later half of the time band for supplying the midnight electric power, therefore, the power transmission efficiency may be improved.

Charged aerosol wind/electric power generator with solar and/or gravitational regeneration

Abstract: On a Charged Aerosol Wind/Electric Power Generator, electrically charged water droplets are dispersed into the wind stream. Using Induction Electric Charging, a water jet issues under water pressure from a small diameter (25-50 μm) orifice, and the jet breaks into charged droplets. A plate orifice 35 μm diameter, and 25 μm long appears optimum; a single jet from such an orifice at a water pressure of 15 psig produces net electric power output substantially exceeding the hydraulic and electric power inputs. A practical Wind/Electric Generator utilizes a multi-orifice array scaled to a kilowatt or megawatt level. A water recovery and pressure regeneration solar and/or gravitational means is described by which water is conserved and the water power is free, so that there is a net output electric power without external power input of any kind, except natural wind and/or solar power.

Electric power system

Abstract: Disclosed is an electrical power system adapted to receiving power from a source of alternating current, typically a small alternator, and supplying a direct current potential to a load. This power system includes two stages, the first stage comprising switchable rectifying devices such as silicon controlled rectifiers which interact with the impedance of the alternator or other source of alternating current power as a switching regulator to create an intermediate direct current potential. The second stage operates from this intermediate direct current potential to produce a slightly lower output voltage, and creates a more accurate regulation than is possible with the first stage alone, the second stage greatly reduces ripple and high frequency noise components contained on the output of the first regulator stage. The second stage serves as an active low pass filter tuned to a desired DC voltage. In combination these two stages produce light weight, highly efficient power systems while providing an output that is essentially pure DC so that load devices such as aircraft radios or electronic computers may be connected directly to the output with or without a battery in parallel with the output. This application is a Continuation-in-part of application Ser. No. 683,771, filed Dec. 19, 1984, now abandoned, and Ser. No. 357,892, filed Mar. 15, 1982, now U.S. Pat. No. 4,490,779.

Physics of semiconductor power devices

Abstract: Semiconductor power devices are designed to rapidly switch or amplify high currents, to support high voltages, and to control electric power. Because of these requirements, their topographies and structures are different from those of small-signal devices. Specific designs are the result of the understanding of the physics of p-n junction HV breakdown, gain variation at high currents, current instabilities, etc. After introducing elementary semiconductor structures, the author reviews the basic principles of the operation of bipolar and field-effect power transistors and thyristors. This is followed by a discussion of phenomena of special interest for power devices; junction avalanche breakdown, the effect of the current level on the current gain, dynamic and static behaviour at high currents and thermal properties and instabilities. The review includes recent advances in device physics and introduces the reader to new methods of improving device performance. Power is a relative concept-at microwave frequencies at few watts is a very large quantity; this review therefore includes a section on microwave power devices.

Automotive/home power interconnection system

Abstract: A system for conveniently and safely accessing and utilizing the electrical system of a vehicle to provide suitable electrical power output for emergency use with conventional appliances and lighting fixtures, by electrifying the existing parallel distribution wiring system of a home or otherwise. Said system may further access and utilize the electrical system of a vehicle to provide suitable electric power for remote or mobile use, and is amenable to automotive, marine, aircraft, industrial or stationary use.

Integrated circuit device

Abstract: PURPOSE:To contrive efficient utilization of the area of an LSI chip by eliminating unnecessary power source network partly and offering the eliminated regions to wirings of a signal line while ensuring the electrical characteristics of circuit in a master slice type integrated circuit. CONSTITUTION:For a master slice chip comprising the cell array in which basic cells are arranged in horizontal and vertical directions repeatedly, lines P1-P5 for the cell rank and lines P11-P15 for the cell column are laid and a lattice- form power source network can be settled. After blocks for composing the predetermined circuit are arranged, potential and current distributions of the power source network are worked out and unnecessary part of the network is eliminated. For the part to be eliminated, one that has no block accepting an electric power from the corresponding part and one that gives no damage on the characteristics such as voltage and current gains in the peripheral blocks when it is eliminated are appropriate. The eliminated part can be utilized as a signal wiring region thereby improving the freedom and capacity of wiring in the master slice type LSI.

Communication Systems for Distribution Automation and Load Management Results of EPRI/DOE Research

Abstract: The Electric Power Research Institute and the U S Department of Energy have completed a jointly sponsored program to develop and test communication systems for distribution automation and load management The program included three power- line-carrier projects, an ultra-high- frequency radio project, and a, telephone project For each project, a two-way (half-duplex) digital communication system was developed to perform such functions as fault location and isolation, distribution feeder switching, load control, time-of-day metering, remote meter reading, and equipment monitoring The results of this research indicate that communication systems in all three technologies (power line carrier, radio, and telephone) have advanced closer to satisfying utility requirements for, distribution automation and load control Research will continue to determine whether these technoiogies will be cost-effective

Electric motor damper drive with backup power pack

Abstract: An electric damper motor drive with a backup power pack is disclosed comprising a reversible electric motor operable in first and second opposite directions in response to first and second distinct forms of electrical energization, respectively. A primary power source normally supplies electrical power to energize the motor in response to a sensed environmental condition. A backup power pack is responsive to the absence of power from the primary power source to supply the first form of electrical energization to drive the motor in the first direction to a predetermined position.

Power steering system

Abstract: An electric-oil pressure power steering system for a vehicle is described which comprises an oil pump driven by an electric motor for supplying power fluid to a power cylinder, a steering wheel connected to a control valve for controlling the supply of the power fluid, and an electronic switching device for controlling the supply of electric power to said motor in response to the change of a vehicle speed, said electronic switching device including a means for controlling continuously the supply of the electric power and a means for controlling discontinuously or variably the supply of the electric power

Power source system for vehicular electronic device

Abstract: Herein disclosed is a vehicular power source system which uses as its load a memory-arithmetic circuit (5) such as a microcomputer. An electric power is supplied to the load (5) through a diode (6) and a constant voltage circuit (4), when a switch (2) for running the vehicle is open, but a booster (3) is operated to supply the power when the switch (2) is turned on. The voltage drop of a battery (1), which may be caused during the running operation of the vehicle, is not transmitted to the load (5), but a constant voltage is supplied to the load (5) at all times so that the storage data of the memory unit (5) is always held.