Abstract: A surge protective device includes an overvoltage protection circuit and a control module coupled to the overvoltage protection circuit that is configured to monitor at least one performance characteristic of the overvoltage protection circuit and is further configured to communicate the at least one performance characteristic to a destination external to the surge protective device.

Abstract: Embodiments include in response to monitoring a processor during operation, detecting a first number of core recovery events in the processor, determining that the first number of core recovery events fulfills a first condition for the first core recovery events threshold, and modifying a value of at least one droop sensor parameter of the processor by a first amount. The at least one droop sensor parameters affects a sensitivity to a voltage droop. In response to modifying the value of the droop sensor parameter by the first amount, a second number of core recovery events is detected in the processor. It is determined that the second number of core recovery events fulfills a second condition for a second core recovery events threshold, and the value of the at least one droop sensor parameter is modified by a second amount.

Abstract: In accordance with at least one aspect of this disclosure, a method can include measuring a voltage across a DC link of a generator system when a generator exciter is inactive and a generator permanent magnet is active, and detecting a short or open permanent magnet generator (SOPMG) fault condition in the generator system with a DC link monitor operatively connected to measure the voltage across the DC link.

Abstract: In accordance with at least one aspect of this disclosure, a system includes a generator control relay configured to electrically connect a generator and an exciter switch drive to drive an exciter switch. A first processor is operatively connected to control a state of the generator control relay to control the electrical connection between a generator and the exciter switch drive. The system includes an exciter drive configured to generate excitation current for field windings of a generator system based on a state of the exciter switch. A second processor is operatively connected to control the exciter drive and to communicate with the first processor during a fault event to place the generator control relay in an open state, disconnecting the generator from the exciter switch drive to prevent generation of excitation current. In certain embodiments, the first processor can include a microcontroller and the second processor can include a voltage regulation processor.

Abstract: Aspects of the present invention relate to a method for controlling an amount of reactive current provided from a wind turbine generator to a power grid during an abnormal power grid event, said wind turbine generator comprising a doubly-fed induction generator having a rotor and a stator, and a power converter coupling the rotor to the power grid, the power converter comprising a grid-side inverter, wherein the method comprises the step of balancing the reactive current provided to the power grid between a reactive stator current and a reactive grid-side inverter current, wherein the reactive grid-side inverter current is controlled in accordance with a reactive current capacity of a grid breaker receiving the reactive current provided by the grid-side inverter. Aspects of the present invention also relate to a wind turbine generator being capable of performing the method.

Abstract: A method for enhancing an over-voltage protection by an over-voltage protection device for a generator is provided. The device includes a high voltage excitation off (HEO) circuit lowering an over-voltage level by an over-voltage lockout control value and a voltage-dependent Ki-Kp (VoKiKp) circuit 30 decreasing an over-voltage generation time by a voltage difference value of a battery voltage. A generator setting voltage is provided to operate the over-voltage and the voltage difference value of the generator 1. The over-voltage level is lowered and the over-voltage generation time is minimized, thereby enhancing the over-voltage protection of the regulator of the generator.

Abstract: Systems and methods for fault detection and protection in electric power systems that evaluates electromagnetic transients caused by faults. A fault can be detected using sampled data from a first monitored point in the power system. Detection of fault transients and associated characteristics, including transient direction, can also be extracted through evaluation of sample data from other monitored points in the power system. A monitoring device can evaluate whether to trip a switching device in response to the detection of the fault and based on confirmation of an indication of detection of fault transients at the other monitored points of the power system. The determination of whether to trip or activate the switching device can also be based on other factors, including the timing of receipt of an indication of the detection of the fault transients and/or an evaluation of the characteristics of the detected transients.

Abstract: The invention relates to an overvoltage arrester for an electrical drive, especially a drive for a motor vehicle. The overvoltage arrester is designed to be connected to an on-board power supply system of a motor vehicle. The overvoltage arrester is designed to reduce any overvoltage produced in the on-board power supply system when a load is switched off. According to the invention, the overvoltage arrester is connected to a control unit for an electronically commutated electrical machine. The overvoltage arrester has an input for an on-board power supply system and is designed to detect when a pre-determined voltage value is exceeded and to produce an overvoltage signal depending on whether the voltage value is exceeded. The control unit is designed to transfer the electrical machine from an operating mode in which the machine generates power to an at least partial power-loss mode or to a mode in which it operates as a motor.

Abstract: A power dissipating arrangement for dissipating power from a generator in a wind turbine is provided. The generator comprises a plurality of output terminals corresponding to a multi-phase output. The power dissipating arrangement comprises a plurality of dissipating units, a plurality of semiconductor switches, a trigger circuit for switching the semiconductor switches and a control unit for controlling the operation of the trigger circuit, thereby controlling the switching of the semiconductor switches.

Abstract: An energy storage system having a number of trays with each tray having a number of battery cells in which power is controllably stored and discharged. A first Battery Management System (BMS) is electrically coupled to a tray contained in a rack of trays. A second BMS is electrically coupled to and controls the first BMS. The first BMS includes a control unit electrically coupled to and controlling the battery cells. It further includes a switch unit electrically coupled to the control unit and selectively applying driving power according to a control signal from the second BMS.

Abstract: Provided are a driver circuit which suppresses damage of a semiconductor element due to ESD in a manufacturing process, a method of manufacturing the driver circuit. Further provided are a driver circuit provided with a protection circuit with low leakage current, and a method of manufacturing the driver circuit. By providing a protection circuit in a driver circuit to be electrically connected to a semiconductor element in the driver circuit, and by forming, at the same time, a transistor which serves as the semiconductor element in the driver circuit and a transistor included in the protection circuit in the driver circuit, damage of the semiconductor element due to ESD is suppressed in the process of manufacturing the driver circuit. Further, by using an oxide semiconductor film for the transistor included in the protection circuit in the driver circuit, leakage current in the protection circuit is reduced.

Abstract: Systems and methods for monitoring excitation of a generator based on a faulty status of a generator breaker are provided. According to one embodiment, a system may include a controller and a processor communicatively coupled to the controller. The processor may be configured to receive, from a contact associated with a generator breaker, a reported status of the generator breaker, receive operational data associated with one or more parameters of a generator associated with the generator breaker, and correlate the reported status of the generator breaker and the operational data. Based on the correlation, the processor may establish an actual status of the generator breaker, and, based on the actual status, selectively modify a mode of excitation of the generator.

Abstract: A mobile generator for generating a direct voltage for a tool supplied with direct current includes an alternating-voltage generator (1), an electronic control unit (3), a rectifier unit (2), which has a direct-voltage output (6) with live conductors (9, 10) for connecting the tool (11), and a protective device (14). The protective device is between the live conductors (9, 10) and a protective potential (18), especially ground or a protective wire. The protective device (14) has an insulating spark gap (15) responding in the case of an error with a defined response voltage (UT) for grounding the live conductors (9, 10).

Abstract: An example method of detecting a generator overvoltage condition includes predicting a primary control current to provide a predicted control current, monitoring the primary control current, and detecting a generator overvoltage condition based on a comparison of the predicted control current to the primary control current. The method interrupts the primary control current based on the comparing.

Abstract: A brushless wound field synchronous generator configured to generate an output power to drive an electrical load includes a rotating rectifier assembly. The rotating rectifier assembly includes a rotating diode assembly and a field effect transistor (FET) to control voltage across the rotating diode assembly.

Abstract: Example embodiments disclose a drive system including a machine including a plurality of phases and configured to generate power based on a plurality of phase currents, each respectively associated with the plurality of phases and a direct current (DC) bus, operatively connected to the machine. The DC bus includes a high-side line, a low-side line, and an inverter including a plurality of switching systems, operatively connected between the high-side line and the low-side line, the plurality of switching systems, each configured to output a respective one of the plurality of phase currents. The drive system also includes a controller, operatively connected to the DC bus and the machine, the controller configured to determine if a failure exists in the drive system based on the plurality of phase currents and a DC bus voltage, the DC bus voltage being a voltage across the high-side line and the low-side line.

Abstract: Disclosed is an alternator overvoltage protection circuit having a TRIAC and a MOSFET. The TRIAC is electrically connected to the MOSFET and the TRIAC is electrically connected to a magneto. The TRIAC is configured to ground the magneto when triggered by the MOSFET. The MOSFET is electrically connected to an alternator and configured to conduct when the alternator operates in an overvoltage condition. Also disclosed is a method of alternator overvoltage protection for a piece of outdoor power equipment, the method including providing a TRIAC and an alternator rotated by an engine having a magneto, wherein the alternator outputs a voltage when rotated by the engine. The method further includes configuring the TRIAC to ground the magneto when the alternator operates in an overvoltage condition, thereby disabling the magneto, which stops the rotation of the engine and stops the alternator from outputting voltage.

Abstract: Systems and methods for monitoring excitation of a generator based on a faulty status of a generator breaker are provided. According to one embodiment, a system may include a controller and a processor communicatively coupled to the controller. The processor may be configured to receive, from a contact associated with a generator breaker, a reported status of the generator breaker, receive operational data associated with one or more parameters of a generator associated with the generator breaker, and correlate the reported status of the generator breaker and the operational data. Based on the correlation, the processor may establish an actual status of the generator breaker, and, based on the actual status, selectively modify a mode of excitation of the generator.

Abstract: A generator system includes a generator and a generator control unit (GCU). The GCU is connected to monitor and regulate the generator output voltage. The GCU includes a protection signal processor that receives monitored generator voltages and executes software to detect an overvoltage condition. The GCU further includes redundant, hardware based overvoltage detection that detects a peak voltage value associated with the monitored generator voltage and includes a fast overvoltage detection circuit that generates a first overvoltage fault signal if the peak voltage value is greater than a first threshold value and includes an inverse overvoltage detection circuit that generates a second overvoltage fault signal if the peak voltage value is greater than a second threshold value for a duration of time that varies with a magnitude of the peak voltage value.

Abstract: A switching assembly includes a first terminal and a second terminal, a first switch connected to the first terminal, and a second switch connected to the second terminal. The switching assembly further includes a rectifier bridge connected between the first switch and the second switch, and a third switch connected between the first terminal and the second terminal. The switching assembly also includes a control unit that selectively opens and closes the first switch, the second switch and the third switch, and selectively turns on and off the rectifier bridge.

Abstract: A generator protection device is provided. The generator protection device includes a safety factor estimation module configured to estimate a safety factor as a function of a terminal voltage (VS) of a source-end generator, and a swing center voltage (SCV) between the source-end generator and a receiving-end generator. The system further includes a comparison module configured to compare the estimated safety factor with a defined safety threshold limit, and a decision module configured to trigger an alarm or a generator circuit breaker trip action or both, based on the comparison between the estimated safety factor and the defined safety threshold limit.

Abstract: The present invention provides an islanding detection method and an islanding detection system. The method includes: acquiring a voltage signal at a grid-connected node of a power generation system, and extracting phase information of the voltage signal; constructing a slip-mode frequency shift islanding detection curve in the form of a quadratic function according to the phase information; and generating a disturbance signal according to the slip-mode frequency shift islanding detection curve, and sending the disturbance signal to an inverter of the power generation system. The method and system can avoid a non-detection zone, and can perform an inverter islanding detection in a fast and accurate manner under simple control.

Abstract: The present invention includes a method for providing ground fault protection to a generator. The method includes determining the existing state of the generator and second, determining the updated alarm or trip conditions of a relay connected to the generator in view of the existing state of the generator. This includes estimating a ratio of the magnitude of the 3rd harmonic neutral voltage to the magnitude of the 3rd harmonic terminal voltage of a generator, along with calculating the residual 3rd harmonic voltage from the estimated 3rd harmonic ratio. From this, a comparison is made between the energy of the residual voltage with a fractional energy of the 3rd harmonic neutral voltage. Based on this comparison, an alarm or trip condition is signaled when the energy of the residual voltage is greater than the fractional energy of the 3rd harmonic neutral voltage.

Abstract: A transformer arrangement for a wind energy system is described. The transformer arrangement includes a transformer core; a primary winding wound around the transformer core and adapted for being connected to an electrical load; a first secondary winding wound around the transformer core and adapted for being connected to a power source; and a control system for controlling the first transformer. Further, the transformer arrangement includes a part of a second secondary winding adapted for being connected to a power source and adapted for reducing at least one of for the voltage of the first secondary winding and the voltage applied to the electrical components of the wind turbine in the case of an overvoltage event.

Abstract: Aspects of this disclosure relate to coupling and decoupling a power source of a device with circuitry within the device. For example, in aspects of this disclosure, when a short develops within the device, a switch circuit may decouple the power source from the some of the circuitry within the device. Decoupling the power source when a short develops may extent the operational time of the power source, and may reduce thermal excursion.

Abstract: An electrical power protection system, includes a generator configured for supplying Direct Current (DC) power to a load bus, the load bus in electrical communication with a bus circuit; a generator control unit being configured for regulating the output voltage supplied by the generator; a bus contactor in serial communication with the bus circuit, the bus contactor including logic circuits configured for detecting an overcurrent in the bus circuit, the overcurrent representative of a ground fault in the bus circuit; and a capacitor bank coupled to the generator for selectively supplying an excitation voltage through a diode switch to the generator during the ground fault in the bus circuit.

Abstract: A steering control apparatus includes a direct current power source, a three-phase alternating current motor, and a motor driving circuit. An emergency switching element is provided on at least two phases of a three-phase power supply line connected to the three-phase alternating current motor within the motor driving circuit, and the emergency switching element is turned off when an abnormality occurs such that the motor driving circuit is disconnected from the three-phase alternating current motor. The emergency switching element is a MOSFET, and the MOSFETs are provided in pairs in each of the two phases of the three-phase power supply line. Further, parasitic diodes of the pairs of MOSFETs are disposed in opposite orientations to each other.

Abstract: A tubular tower (11), of a wind energy plant (10) with a current conduction means system (25, 35) for transmitting electrical power from a generator on the tower (11), to a power module at the base of the tower. The current conduction means system (25, 35) has three electrical conductors (27.1, 27.2, 27.3; 37.1, 37.2, 37.3; 45.1, 45.2, 45.3) arranged next to one another. A housing (26, 36, 46) is connected to the inner tower wall at predetermined distances using connecting devices which have electrical cross-sections conducting with the tower wall. The distances between the connecting devices in the longitudinal extent of the tower (11) and the cross-sections of the connecting devices between the housing (26, 36, 46) and the tower wall are dimensioned such that during a fault, the voltage drop between the tower wall and the housing (26, 36, 46) does not exceed a predetermined touch voltage.

Abstract: An overvoltage protection system for a power generating system includes a generator control relay (GCR) controlling a conduction path through a generator exciter field, a flyback impedance in parallel communication with the generator exciter field, the flyback impedance configured to dissipate energy from the generator exciter field in response to opening of the conduction path, a gate drive configured to open and close the GCR, and an overvoltage prevention unit in signal communication with the gate drive, the overvoltage prevention unit configured to monitor a voltage and a current associated with the generator and selectively open and close the conduction path in response to the monitored voltage and current.

Abstract: An electronic device is disclosed that comprises a housing 81 and a flexible display, which may have respective portions 82a, 82b, 82c and 82d. The portions may be accommodated between respective hinges 84a, 84b, 84c, 84d, which are arranged as a mechanism for enabling a transition between the first mechanically stable position and a second mechanically stable position. The display is viewed from a direction 85. The hinges are operated independently from each other, enabling a plurality of angulations of the flexible display with respect to the housing 81.

Abstract: A system for monitoring a machine is provided. The system includes a digital protective relay, a communications network, and a central server. The digital protective relay is connected to the machine, and samples at least one parameter of the machine at a rate of at least about twelve samples per power cycle. The central server is located remotely from the machine for receiving the at least one parameter from the machine. The communications network provides a connection between the digital protective relay and the center server for sending a data signal representing the at least one parameter of the machine.

Abstract: A mobile generator for generating a direct voltage for a tool supplied with direct current includes an alternating-voltage generator (1), an electronic control unit (3), a rectifier unit (2), which has a direct-voltage output (6) with live conductors (9, 10) for connecting the tool (11), and a protective device (14). The protective device is between the live conductors (9, 10) and a protective potential (18), especially ground or a protective wire. The protective device (14) has an insulating spark gap (15) responding in the case of an error with a defined response voltage (UT) for grounding the live conductors (9, 10).

Abstract: An example method of detecting a generator overvoltage condition includes predicting a primary control current to provide a predicted control current, monitoring the primary control current, and detecting a generator overvoltage condition based on a comparison of the predicted control current to the primary control current. The method interrupts the primary control current based on the comparing.

Abstract: A fault sensor is disclosed for detecting the failure of a surge suppression device such as a metal oxide varister (MOV). The fault sensor comprises a fault sensor conductive layer overlaying an insulated portion of the surge suppression device. A fault sensor connector is connected to the fault sensor conductive layer for conducting a fault current upon a failure of the insulated portion of the surge suppression device.

Abstract: A processing arrangement for the fault situation of a local electric power transmission grid comprises a generator-specific element arranged to monitor the fault situation of a data communication bus and the statuses of the switches of the electric power transmission network and to compare the status data concerning the same switch. In case of a fault situation the generators change into droop control only if there are no other possibilities to continue with the normal adjustment of the generator.

Abstract: A generator controller provides independent and redundant overvoltage protection to an associated generator. The generator controller monitors the generator output at a first point of a regulation and a second point of regulation. A generator control unit (GCU) provides overvoltage protection based on the generator output monitored at the first point of regulation, including at least one of tripping a first generator control relay (GCR) to remove excitation from an exciter winding and tripping a generator line contactor (GLC) to disconnect the generator output from a bus. A overvoltage protection unit (OPU) provides independent, redundant protection based on the generator output monitored at the second point of regulation, including at least one of tripping a second GCR to remove excitation from the exciter winding and tripping the GLC to disconnect the generator output from the bus.

Abstract: A generator includes a permanent magnet generator, an exciter and a main generator mounted for rotation on a shaft. The main generator is configured to produce a voltage output. A generator control unit includes a circuit configured to provide current from the permanent magnet generator to the exciter. A switch is provided in the circuit and is configured to change between open and closed conditions. The switch is configured to flow current in the circuit in the closed condition and interrupt current flow in the open condition. An overvoltage limit controller is programmed to determine an amount of overvoltage of the output voltage exceeding a desired voltage.

Abstract: An aircraft electrical system comprises a generator to be driven as part of a gas turbine engine. The generator supplies electrical power to a plurality of accessories associated with the gas turbine engine, and to an aircraft power bus in parallel to the supply to the accessories. A control detects a short circuit on the aircraft power bus. When a short circuit is detected on the aircraft power bus, a switch is driven open to disconnect the aircraft power bus from the generator. In this manner, the power will continue to be delivered to the plurality of accessories. In a separate feature, a control voltage is provided by an auxiliary permanent magnet generator to a voltage regulator for the main generator.

Abstract: A protective apparatus is for a distributed resource of a utility grid. The protective apparatus includes a processor having an input structured to input frequency of the distributed resource, a first output structured to control speed of the distributed resource, a second output, and a routine structured to actively bias engine-generator speed of the distributed resource through the first output, and detect a predetermined change in the frequency of the distributed resource from the input and responsively indicate the unintentional island condition through the second output. The protective apparatus also includes a circuit interrupter.

Abstract: A method for protection of an energy storage source (2), in particular a battery of a motor vehicle, against possible overloading caused by prolonged application of an electric voltage to the energy storage source, this voltage being generated at least partially by a rotary electric machine (1) such as an alternator or an alternator-starter, the method comprising the following steps: permitting measurement of a charge level of the energy storage source, this charge level being represented for example by a voltage measured at the terminals of the energy storage source or a PWM signal, while the rotary electric machine is functioning in a predetermined functioning mode, and electric excitation is being applied to it; comparing a value (SENSE) of this measurement with a reference value (Max_SP); if the value measured for the energy storage source is greater than the reference value, interrupting the excitation applied to the rotary electric machine.

Abstract: An arrangement for protecting equipment of an AC electrical power system comprises first means configured to measure the frequency of the current and voltage at at least one location in the electrical power system along an interconnection between two theoretical electric machines of an equivalent two machine system. Fourth means are configured to use the values of the frequency of the current and voltage measured to determine whether a power swing has occurred and if an occurrence of a power swing has been determined determine whether the measuring location is located on a motor side or a generator side of a potential pole slip electrical centre along said interconnection, the electrical centre being defined as the location where the voltage becomes zero during a pole slip, and send this information further to third means for use in a control for protecting equipment of the electrical power system.

Abstract: A power limiting system for multiple electric motors includes an electrical power generating component, such as an alternator, and a plurality of motor controllers connected to an electrical bus. Each motor controller compares the voltage on the bus to a specified minimum voltage and a specified maximum voltage, and reduces its electric power output if the voltage on the bus is less than the maximum voltage while continuing to operate the electric motors.

Abstract: A power circuit includes a gate drive sever comparator circuit operable to disconnect a pre-drive transistor circuit from ground in response to an over voltage fault condition. A back-up gate drive comparator circuit operable to switch a reference directly into a multiple of shunt MosFets such that the multiple of shunt MosFets are turned on to reverse the over voltage fault condition until voltage drops and the gate drive sever comparator circuit and the back-up gate drive comparator circuit turn off to maintain a regulated voltage between comparator controlled limits.

Abstract: A driver circuit including a pre-driver B1 that operates by receiving operating power from a first power supply VDDI, and a main-driver B2 that receives operating power from a second power supply VDDE, amplifies an output signal from the pre-driver B1, and outputs the amplified signal. It also includes a first switch B4 between the first power supply VDDI and the pre-driver B1. It also includes a second switch B5 between the second power supply VDDE and the main-driver B2. A overvoltage protection sequence circuit B3 controls the On/Off states of the first switch B4 and the second switch B5 to controls the On/Off order of the pre-driver B1 and the main-driver B2. By doing so, the overvoltage protection sequence circuit B3 prevent an overvoltage from being applied to the driver circuit, especially to the main-driver B2.

Abstract: An electrical system for connecting a wind turbine to a power grid that includes: a frequency converter that converts electric power produced by a generator of the wind turbine into electric power that is synchronized with the electric power of the power grid; a transformer that steps up the voltage for connection to the power grid, the transformer being disposed between the frequency converter and a connection to the power grid; and a grid-side crowbar circuit; wherein the grid-side crowbar circuit is configured to apply a short circuit to the electrical system upon the detection of a fault.

Abstract: A protection circuit which is capable of preventing a faulty operation resulting from an abnormal control signal a method for operating the same, a flat display device using the same, and a method for driving the flat display device using the same are disclosed. The protection circuit includes a reference voltage output circuit for outputting a first reference voltage corresponding to a minimum allowable voltage of a control signal and a second reference voltage corresponding to a maximum allowable voltage of the control signal, and a comparison circuit, comparing a level of the control signal with the first reference voltage and second reference voltage and supplying a output control voltage corresponding to the control signal representing the a high-logic state to the controller when the level of the control signal has a value between the first reference voltage and the second reference voltage.

Abstract: A typical power plant has a plurality of generators; at least one load; at least one bus interconnecting the generators and the at least one load. The plant is operated on an uncorrected droop configuration for speed control and voltage control. The plant further includes a monitoring module for monitoring at least one of a plurality of signals; a calculating module for calculating a fault based on a comparison of predefined values expected from normal droop operation with respect to monitored values obtained from the monitored signals; and a control module for providing an order to bring additional generating capacity on line, for tripping a generator if a fault has been identified with respect to a single generator or for tripping a tie breaker to provide bus to bus isolation if an identified fault cannot be isolated to a single generator.

Abstract: A vehicle electrical system comprises a generator and a control device coupled with the generator and operable to protect the generator from catastrophic failure while providing the electrical load in the electrical system with sufficient electrical power. The control device determines a loss of symmetry between two alternating phase signals generated by a first and second phase windings of a single or multiple stator generator. In particular, the control device determines a first and second average values of two of the two or more alternating phase signals and either limits or ceases the total electrical output current of the generator, via a generator output power controller, when the first average value differs from the second average value by a predetermined value. The control device may alternatively be configured to generate an error signal without varying the generator's total electrical output current even in the event of a malfunction.

Abstract: In a vehicle electrical system powered by a battery for supplying a plurality of loads, an integrated module is provided between the positive terminal of the battery and the loads, and the integrated module includes an arrangement for detecting a state of charge of the battery, a control unit for power management of the vehicle electrical system, and at least one supply output for supplying power to the loads.

Abstract: A car power source apparatus includes a battery array that has a plurality of battery units connected in series, a battery over-charge and over-discharge detection circuit, selection switches that sequentially input battery unit voltages to the over-charge and over-discharge detection circuit, a reference voltage circuit that inputs reference voltages to the over-charge and over-discharge detection circuit, and a control circuit that controls selection switches and the reference voltage circuit. The control circuit controls the selection switches to input battery unit voltages to the over-charge and over-discharge detection circuit to determine over-charge and over-discharge.