Abstract: An automatic load distributing apparatus for generators is of simple construction and occupies a small space and can automatically distribute loads evenly on respective engines upon parallel load operation of generators of different capacities and provide labor saving of operation. The automatic load distributing apparatus for generators comprises a plurality of engines for driving a plurality of generators connected in parallel to a common load, a plurality of fuel injection pumps and a plurality of load distributing units for distributing outputs corresponding to the load to the engines.

Abstract: A power conversion system allows for redundant starting and generating functions together with fault tolerant operation through the multiple use of power conversion equipment.

Abstract: An energy storage and distribution system provides energy from a first energy related infrastructure characterized by a first energy grid to a second energy related infrastructure characterized by a second energy grid that is substantially independent of the first energy grid. The system includes an energy storage facility that is located in substantial proximity to a common boundary of the first and second energy related infrastructures, and a first energy transport mechanism that is coupled to the first energy related infrastructure and is capable of providing energy for storage in the energy storage facility. The system also includes a second energy transport mechanism that is coupled to the energy storage facility and is capable of providing energy from the energy storage facility to the second energy related infrastructure. Each of the first and second energy grids has an electrical power generation unit and high voltage A/C transmission lines.

Abstract: A system is provided to effectively use the electric charge of a capacitor provided for an inverter in an electric vehicle when the capacitor discharges and to decrease the time required for discharge. An inverter for converting the DC electric power of a main battery into AC electric power to drive a traveling motor is provided with a smoothing capacitor to be charged through a precharge contactor. A DC/DC converter is used to charge a sub-battery using the electric power from the main battery when an electric vehicle runs. When the capacitor discharges, the electric charge of the capacitor is used to charge the sub-battery through the DC/DC converter. Because no discharge circuit is used when the capacitor discharges, it is possible to complete discharge in a short time and without the generation of heat by the discharge circuit.

Abstract: An alternating current power supply for providing a high-voltage alternating current power output from a first low-voltage alternating current power source and a second low-voltage alternating current power source is disclosed. A first alternating current low-voltage power input is coupled to the first low-voltage alternating current power source, and a second alternating current low-voltage power input is coupled to the second low-voltage alternating current power source. A switch simultaneously couples the first low-voltage power input to a first output conductor and the second low-voltage power input to a second output conductor, thereby providing a high-voltage power output between the output conductors. A switch control activates the switch responsive to a phase difference, typically 180 degrees, between the first alternating current power source and the second alternating current power source.

Abstract: An isolation circuit for use in a power plant having a first power supply that powers a first load and a second power supply that powers a second load. The first and second power supplies are cross-couplable via a first and second auxiliary path to allow the first power supply to power the second load and the second power supply to power the first load. The first power supply is subject to a reverse current by way of the first auxiliary path. The isolation circuit includes a first switch, located in the first auxiliary path, that substantially reduces the reverse current flowing into the first power supply thereby enhancing an isolation of the first power supply. A controller is, also, provided that monitors the first switch thereby enhancing a reliability of the power plant.

Abstract: A DC power distribution system can be configured to utilize a variable number of AC power distribution units. Installation of a converter unit in place of a PDU and resetting of associated switches permits inexpensive and rapid reconfiguration of the system without interrupting power supply to current receiving units. Techniques such as mechanical keying and sense switches minimize the possibility of human error in the reconfiguring operation.

Abstract: Semiconductor processing tools in a semiconductor processing facility are coupled to communicate with a power management system. The power management system monitors the power consumption status of each of the semiconductor processing tools. Using the power consumption status of each of the semiconductor processing tools, the power management system stages the operation of the semiconductor processing tools so as to maintain the power consumption of the semiconductor processing facility below a predefined maximum power consumption. Limiting the power consumption to less than the predefined maximum power consumption reduces the per die processing costs without incurring the expense of building a new semiconductor processing facility or without modifying the semiconductor processing tools for larger batch sizes or for greater throughput.

Abstract: In an electric car drive system having a car drive motor powered by a mounted direct current power supply, a control system including a signal generating means is provided to generate signals which control motor speed. The direct current power supply is composed of a power battery having secondary cells connected to the motor and an energy battery formed by fuel cells connected in parallel to said power battery via an energy battery control switch. The electric car drive system is composed of a charge control means which charges the power battery using the energy battery if the charge of the power battery is below the specified value when said key switch is turned off, and suspends charging if the charge is equal to or greater than the specified value.

Abstract: An analog-to-digital converter comprises the following elements. A reference voltage generation circuit is provided for dividing a reference voltage into a plurality of divided reference voltages having voltage levels different from each other. A plurality of comparators are provided, each of which has a first input terminal connected to an analog input line for fetching analog signals and a second input terminal connected to the reference voltage generation circuit for fetching a corresponding one of the divided reference voltages so as to compare the analog signals with the divided reference voltage. Each of the comparators has an output terminal through which an output digital signal is outputted.

Abstract: The method of interconnecting first and second synchronous polyphase AC networks is for regulating transfer of active power from one of the AC networks to the other. The method involves the steps of, for each phase line of the first AC network, connecting a first end of a first reactive element to the phase line of the first AC network; connecting a first end of a second reactive element to the phase line of the first AC network; applying to a second end of the first reactive element a first phase voltage derived from a second AC network; applying to a second end of the second reactive element a second phase voltage derived from the second AC network, the second phase voltage being phase shifted with respect to the first phase voltage. In a preferred method according to the invention, one of the reactive elements is inductive, and the other of the reactive elements is capacitive.

Abstract: A synchronizing device for a parallel connection of a synchronous generator and an a.c. network. The device includes a measuring circuit for measuring the voltage and frequency of the generator and the a.c. network and for measuring the phase angle between the generator and the a.c. network. The measuring circuit includes control outputs for regulating the rotational speed of the generator drive. A set value for the generator frequency includes a defined slip at the start of balancing. The measuring circuit also regulates the voltage output of the generator to match the a.c. network voltage. Once the phase angle between a.c. network voltage and generator voltage has fallen below a predefined value, null balance occurs.

Abstract: A transfer switch system includes a controller which sends separately timed restart signals over a communications network to an addressable relay associated with each load in order to sequentially restart the loads following a transfer. When the loads are elevators, the controller sends a prepare to transfer signal to each elevator through the associated addressable relay directing the elevator to park at a floor with its doors open and delays making a discretionary transfer until all elevators send a reply message over the network that they are appropriately parked. A message from the utility directing a reduction in use of their power can be sent to the controller over the communications network through an additional remote station. The controller can then transfer to the alternate power source and/or send messages to selected loads to shut down.

Abstract: A fault tolerant isolation system providing fault tolerant electrical isolation between different components receiving power from separate power sources regardless of which of the power sources fails. One power source provides operating voltage to an isolation device, which is a transceiver, buffer, quick switch, etc. The other power source activates a transistor switch coupled to the output enable input of the isolation device, and a current limit device is provided between the output enable and power inputs of the isolation device. In this manner, failure of either power source disables the isolation device and therefore provides fault tolerant isolation between the devices on either side. In the preferred embodiment, the isolation device acts as a high impedance open switch if its power is removed thereby isolating the devices on either side.

Abstract: A method for performing a voltage stability security assessment for a region of an electric power transmission system having a plurality of buses and a plurality of sources of reactive reserves coupled thereto. The plurality of buses are grouped into a plurality of voltage control areas such that each of the buses within each voltage control area has a substantially similar reactive margin and voltage at the minimum of the corresponding reactive power versus voltage relationship. A corresponding reactive reserve basin is determined for each of at least one of the voltage control areas. Each reactive reserve basin comprises at least one of the sources of reactive reserves selected in dependence upon a measure of the reactive reserves depleted at a predetermined operating point of the electric power transmission system. A single contingency analysis is performed by computing a corresponding quantity for each reactive reserve basin in response to each of a plurality of single contingencies.

Abstract: A power supply system for controlling supply of power to several inductive loads has a power monitor and a processor that determines when power consumed exceeds the capacity of the system. When overload is detected, hardware rapidly disconnects loads of low priority. A software register is loaded with software controlling staggered reconnection of the loads when power capacity becomes sufficient again. If capacity is sufficient, all the loads may be reconnected at the same time.

Abstract: An energy supply system operates to supply heat energies, such as cooling water, steam, heating water, etc. to a community, and the system has a function for predicting a future energy demand of the community and to correct it. In a system having an energy plant to store energy and an energy supply pipeline network for connecting the energy plant to the community, the system includes an energy demand plan making section for predicting an energy demand of the community on the basis of past cases of energy supply and for formulating an energy demand plan with respect to time, and an energy demand variation detecting section for determining a variation of the energy demand from the energy demand plan by using a personnel flow measured value measured by personnel flow measuring apparatuses provided at paths to or positions of the community as a parameter. The variation of the future energy demand of the community is predicted and energy which accomodates the determined variation can be prepared.

Abstract: An improvement in a control for a DC link power converter includes a phase command signal generator responsive to DC power on a DC link wherein the phase command signal generator develops a phase command signal for a control of the power converter whereby a parameter the DC power is caused to approach a certain level.

Abstract: A switching system of the present invention is formed of two identical units. e.g. printed circuit board, the primary and the backup units W & P. Each unit has a switching circuit 1 such that upon receiving a first alarm signal generated due to a malfunction taking place in a main circuit 6(W) of the primary unit W, the switching circuit 1W of the primary unit transmits a second alarm signal S.sub.4 (W) to switching circuit 1P of the standby unit P, then the switching circuit 1P of the standby circuit 1P enables an output of main circuit 6(P) on the standby unit as well as transmits a control signal S.sub.9 (P) to disable an output of main circuit 6(W) of the primary unit. A plurality of the units may form a group so that two groups are in the relation of the primary and the backup. A first unit in the group collects the alarm in the own group and communicates with the first unit of the other group, so that the switching are carried out by the whole group.

Abstract: The present invention involves a connector for inductively coupling to a multi-wire data bus utilizing a magnetic core and associated coil for inducing signals upon the bus and for sensing such signals on the bus. The connector includes a pair of magnetic members disposed on either side of the magnetic core for attenuating common mode energy generated within the connector at about the same frequency as that of the primary signal appearing on the data bus.

Abstract: A power supply system for powering a plurality of loads. The system includes a plurality of energizeable power supply circuits each associated with one of the loads for supplying power thereto in response to a power supply circuit control signal. An actuable power sharing arrangement is connected to all of the power supply circuits to facilitate sharing of power among the power supply circuits in response to a power sharing control signal. In addition, a control circuit generates the power supply control signals to individually controlling energization of each of the power supply circuits and the power sharing control signal to maintain the power sharing arrangement in an actuated condition when the power supply circuit control signals are controlling all of the power supply circuits to be energized, and otherwise maintaining the power sharing arrangement in a de-actuated condition.

Abstract: A distributed control system for a plant includes an electric equipment room for supplying electric power to a plurality of field apparatuses constituting parts of the plant by way of a plurality of operation terminals. Apparatuses for controlling the function units are provided distributively in the field in which the field apparatuses to be controlled are installed. Operation terminals to be controlled by the control apparatus are installed in the field.

Abstract: Each end of a power wiring is connected to a first or a second power supply circuit, respectively. These two power supply circuits are activated alternately allowing for some time-overlap. As a result, current flowing in the wiring changes its flowing direction alternately to prevent the degradation of the wiring due to the electro-migration phenomena.

Abstract: A redundant power bus arrangement for electronic circuits controls the application of voltage from a power source to an active circuit card and a standby circuit card. Current limited switches are used to connect the power source to the active or standby circuits. A switch control circuit controls the conductive state of the current limited switches in response to a control signal generated by at least one of the controlled circuits. The maximum current permitted by each of the current limited switches is less than the maximum output current rating of the power source, thereby preventing a short on a power bus within one of the controlled circuits from affecting the voltage available for the other controlled circuit.

Abstract: An electric utility sub-station having two transformers which transmit electric energy to customers in different service areas. A throwover is provided which is operative, when a failure occurs in one transformer, to switch the load normally carried by the failed transformer over to the other transformer which then carries the load of both transformers. Operation of the throwover is blocked when the total demand load on both transformers exceeds the capacity of either transformer.

Abstract: The present disclosure describes a method and a system for interconnecting a first and a second three-phase alternating electric networks.

Abstract: This invention relates to a bus configuration for a dual channel variable speed constant frequency motor/generator aircraft power system providing for both power generation and engine starting. The subject invention provides for isolation of faults which can occur in long power feeders. Further, the subject invention provides for a novel start mode of operation which allows one channel to provide power to the other channel, thereby avoiding inefficient multiple converter operation and potentially faulty power buses. The bus configuration provides for coupling a first motor/generator to a second motor/generator via a first converter to thereby allow th first motor/generator, operating as a generator, to supply variable frequency power to the first converter, the first converter supplying variable frequency power to the second motor/generator to operate the second motor/generator as a motor.

Abstract: In aircraft applications, it may be necessary or desirable to transfer one or more loads between a variable speed, constant frequency (VSCF) power generating system and a further source of AC power. Prior controls for effecting such transfer, however, have been unduly complex. In order to overcome this problem, a control for a VSCF system senses the deviation of a parameter of the power developed by an inverter of the system relative to a parameter of the power developed by an AC power source and controls the inverter in accordance with such deviation to cause the parameter of the power developed thereby to approach the parameter of the power developed by the AC power source. The inverter and the AC power source are connected in parallel across one or more loads when the parameter deviation is within a certain range. Either the inverter or the AC power source is thereafter disconnected a certain time after the two were connected in parallel to complete the power transfer.

Abstract: A power supply system for segmented loads, and having phantom redundancy, is comprised of multiple sets of power supplies, with each set having an output terminal for furnishing load current at a certain voltage. A respective load is connected to the output terminal of each set, and each set also has a current-sharing circuit by which the load currents furnished from the supplies within a set are equalized. Further, all of the supplies from all the loads combined, minus any one supply, have a total current-furnishing capacity which meets the current requirements of all of the loads, but no set of supplies for any one load includes an extra or redundant supply. Also, switches are provided which selectively interconnect, and disconnect, the respecitve current-sharing circuits of the power supply sets such that the supplies of all connected sets furnish equalized load currents.

Abstract: A power transmission system with current-limiting devices having a plurality of power transmission stations for transmitting power from a power-receiving line to respective loads wherein each current-limiting device includes a series circuit constructed of current-limiting elements and a bypass switch connected in parallel thereto. The terminals at one end of the limiting devices are connected to corresponding buses of the transmission stations while the terminals at the other end are connected to each other.

Abstract: A fault-tolerant power distribution system which includes a plurality of power sources and a plurality of nodes responsive thereto for supplying power to one or more loads associated with each node. Each node includes a plurality of switching circuits, each of which preferably uses a power field effect transistor which provides a diode operation when power is first applied to the nodes and which thereafter provides bi-directional current flow through the switching circuit in a manner such that a low voltage drop is produced in each direction. Each switching circuit includes circuitry for disabling the power field effect transistor when the current in the switching circuit exceeds a preselected value.

Abstract: A circuit providing a constant voltage power source for a remotely controlled electrically operated device. The circuit includes a main battery operatively connected with a motor. The secondary battery is connected in parallel with the main battery and operatively connected with a wireless receiver. The negative terminals of both batteries are connected with the receiver through a double-pole single-throw switch and a series connected diode and inductor are interposed between the positive terminals of the batteries so that the secondary battery is charged by the potential of the main battery each time the switch is closed and current flow from the secondary battery to the main battery is prevented by the reverse bias of the diode.

Abstract: In a high-voltage switching system, nodes (1, 2, . . . , 8) are connected in the form of a ring via switching points (12, 23, . . . , ) which in each case contain a circuit breaker. In this system, the breaking currents of the circuit breakers are to be limited and thus the breaking capacity of the circuit breakers provided in the system is to be reduced if a short-circuited part (for example node 1) is separated from a faultless part of the system. This is achieved by opening a switching point (for example 45) of the nodes connected in the form of a ring, between the contact feeders of which switching point and the non-available node (for example (1) in each case at least one available node (for example 2, 3, 4, 5, 6, 7, 8) is provided, via which a component short circuit is fed into the ring.

Abstract: A power supply system including a plurality of power units which supply power to loads through the common bus, wherein the number of power units connected to the bus is larger at least by one than the number of power units necessary to suffice the maximum power consumption of the load. The redundant power unit is ready to relieve a working power source unit in the event of fault. The power supply system incorporates a power monitoring unit which detects the failure of a power source unit.

Abstract: A switchgear installation has at least four junctions connected in the form of an annulus. These junctions are connected with each other by means of interruptable current branches. Each junction of a first group of junctions containing at least two elements may be connected with each junction of a second group of junctions by means of a bridging branch. The bridging branches contain a common power or load switch together with a plurality of disconnecting switches, which are provided between a first supply terminal of the power or load switch and each junction of the first group and between a second supply terminal of the power or load switch and each junction of the second group.

Abstract: In a switching system having n nodes (1,2 . . . 6) which are connected via interruptible current branches (11,12 . . . 16) in the form of a ring, in the case of non-availability of at least one of the nodes or at least one of the switching points provided in the interruptible current branches (for example 11) the nodes which are still available are to be connected in the form of a ring, the structure of which is nearly unaltered in the undisturbed areas of the switching system with respect to the corresponding structure of the ring provided in the undisturbed system. For this purpose, n dual isolating switches (31a, 32a, . . . ) and a circuit breaker (a) are provided which are connected to the nodes (1,2 . . . 6) in such a manner that each node (for example 1) can be connected to any one of the other nodes (for example 2) via one of the n dual isolating switches (for example 31a), the circuit breaker (a) and another one of the n dual isolating switches (for example 32a).

Abstract: This invention serves to reduce the drop of feeder voltage in an electric railway, and relates to a feeder voltage compensating apparatus for electric railways wherein an accumulator and a thyristor rectifier are connected by a thyristor switch circuit which can change-over the charging and discharging directions of the accumulator.

Abstract: A switching device that relates to the arrangement of a switching network for use within an electrical power distribution system. There is an improved security of power delivery to various loads while at the same time enabling a reduction in the number of required circuit breakers and related gear. This network also presents additional options in design and operating modes, when applied to distribution systems. These options result in a reduction in the total installed capacity of the sources together with reduced continuous current and fault current ratings of conductors and interconnected apparatus. The invention provides a switching network has six conducting branches, each branch containing at least one switching means such as a circuit breaker. The branches are connected at their ends to form four 3-sided rings, each branch forming a side of and being shared by two of the rings.

Abstract: A switching network has at least four nodes which can be connected in each case via three interruptable current branches to other ones of the nodes. These nodes can be connected in at least two partial rings. In order to retain the redundancy of such a system in the case of an expansion to more than four nodes with negligible equipment expenditure and, at the same time, little space requirement, the partial rings are constructed in such a manner that they do not have a common node in a preferred embodiment. In this arrangement, each node of a first one of the two partial rings can be connected to a node of a second one of the two partial rings and, conversely, each node of this partial ring can be connected to a node of the first partial ring. The switching network can be advantageously used, in particular, in high-voltage supply systems.

Abstract: An electrical installation for triggering switching functions in motor vehicles, with a central unit producing from input signals, coordinated output signals to switch load switches, and a redundancy unit; the input, respectively, output signals are thereby combined into groups of mutually similar switching functions and the redundancy unit is so connected that it prepares or readies for each group an output signal for the switching function which, in comparison with the other switching functions of the corresponding group, possesses the highest priority.

Abstract: A control for an electrical generating and distribution system utilizing a plurality of interconnected microprocessors. An electrical system, for an aircraft for example, may have two engine driven generators and an auxiliary power unit generator with loads connected to each of the engine driven generators through generator circuit breakers. An electrical distribution bus connected through bus tie breakers interconnects the load circuits and the auxiliary generator so that any one generator can power either or both loads. Each generator has a microprocessor generator control unit responsive to the associated generator conditions to control generator operation. A microprocessor bus power control unit is responsive to distribution circuit conditions and correlates information from the generator control units, contributing to operation of the bus tie breakers, controlling distribution of power from the generators to the loads.

Abstract: An engine generator power supply system comprises a plurality of engine generators; a plurality of separate power feed lines for independently feeding power from respective engine generators to a plurality of loads respectively associated with the separate power feed lines; an electromagnetic contactor inserted in each of the power feed lines, the contactor being normally enabled for feeding power to the plurality of loads from one of the engine generators; and a controller for controlling such that the supply of power from a first engine generator to the plurality of loads is switched to the supply of power from a second engine generator to the plurality of loads at a predetermined time interval.

Abstract: The invention relates to a fault current detection, isolation and clearing system for use in an integrated power generating and distribution arrangement having multiple generators electrically connected to loads and to a distribution bus through circuit breakers. The system includes a power control logic unit and circuit breaker condition detection units which have their outputs electrically coupled to the power control logic unit. Fault current detection circuits are coupled to the electrical connections of the generating and distribution arrangement and have outputs electrically coupled to the power control logic unit. The power control logic unit has an output which is controllingly electrically connected to the circuit breakers to control the circuit breakers and clear faults from the generating and distribution arrangement as a function of circuit breaker conditions and fault currents detected.

Abstract: This invention relates to the arrangement of a switching network intended to be used within an electrical utility station switchyard, which improves the security of power delivery to various loads while at the same time allowing a reduction in the number of required circuit breakers and related gear. The invention is a switching network comprising six conducting branches, each branch containing at least one switching means such as a circuit breaker. The branches are connected at their ends so as to form four 3-sided rings, each branch forming a side of and being shared by two of the rings. As a result, four triple-connected nodes are formed at the end connection points of the branches while the connections between adjacent pairs of switching means within a branch form double-connected nodes. These nodes serve as points for connection thereto of source/load elements, and each node is isolatable from the other nodes by the operation of a maximum of three of switching means.

Abstract: High-voltage high-power, multiphase electrical installation comprising, for each phase, at least two circuit fields that include, in each circuit field, a circuit breaker arranged between two current transformers, each of them discharging into the same load as the homologous current transformers of the other circuit fields having the same phase; isolating switches placed at the ends; earth isolators placed between the isolating switches and the current transformers. The magnetic circuit of the current transformers is crossed simultaneously by the conductor of the phase of the circuit field and by an auxiliary conductor connected; on the one hand, to a ground isolator and, on the other hand, to a ground point.

Abstract: Disclosed is an alternating current transmission, comprising two lines wherein homogeneous phases of different lines are separated from each other by a minimum distance permissible for interphase overvoltages. Installed at the terminals of each of the lines are phase control units varying an angle of phase shift between the voltages of the drawn together phases of the lines. Arranged between homogeneous phases of the different lines, are capacitor banks whereas reactors are installed between the heterogeneous phases of the different lines. The electric current transmission is provided with braking resistors permitting to raise the stability of operation of the generators.