Abstract: A circuit device includes a control circuit configured to control a transistor current based on a detected temperature. The detected temperature is a temperature detected by a temperature sensor circuit that detects a temperature of a transistor. The transistor charges a load to which a power supply voltage is supplied. The transistor current is a current flowing through the transistor during charging. The control circuit reduces the transistor current when the detected temperature is higher than a first threshold value, and increases the transistor current when the detected temperature is lower than a second threshold value lower than the first threshold value.

Abstract: A method for detecting an imminent pole slip of a synchronous generator electrically connected to a power supply network, whereby a signal characteristic of a power fault is detected and an imminent pole slip is determined via a predefinable value when a load angle of the synchronous generator increases, whereby the following steps are performed. Determination of a first load angle during operation without a power fault, determination of a generator frequency as a function of time when a power fault occurs, and precalculation of a second value of a load angle resulting from the power fault by adding the first value of the load angle to a load angle difference occurring during the power fault, whereby this load angle difference is caused by a deviation of a generator frequency relative to a power frequency.

Abstract: Provided is an electronic device including a rotary power generation device using an electret, which is capable of preventing a spiral spring from being wound up or fully extended. The electronic device includes a power generation mechanism including: first rotary member, which is supported in a freely rotatable manner, and has a center of gravity shifted from a rotation center; second rotary member supported in a freely rotatable manner; an elastic member configured to elastically connect the first rotary member and the second rotary member to each other for rotary motions thereof; a stationary member arranged so as to be opposed to the second rotary member; and an electret film formed on a surface of any one of the second rotary member and the stationary member.

Abstract: Methods and apparatus for controlling power conditioners in a distributed resource island are provided herein. In one embodiment, an input of a power conditioner that is operating in a de-energized state and coupled to an islanded grid is compared to an input threshold. When the input exceeds the input threshold, the power conditioner is operated in a soft-grid mode to generate a touch-safe AC voltage that is coupled to the islanded grid. The power conditioner compares an impedance of the islanded grid to a grid impedance range and compares load demand of the power conditioner to an activate threshold; when the impedance is within the grid impedance range and the load demand exceeds the activate threshold, the power conditioner is activated to operate proximate its nominal output voltage.

Abstract: The present application provides a power generation system. The power generation system may include a core turbine positioned about a core rotor shaft, a power turbine positioned about a power rotor shaft, a synchronous generator including a generator rotor shaft coupled to the power rotor shaft for rotation therewith, and an electronic controller in operable communication with the synchronous generator. The synchronous generator may be configured to generate reactive power for or absorb reactive power from an electric power grid when the power generation system operates in a reactive power mode. The electronic controller may be operable to cause the core rotor shaft to rotate when the power generation system operates in the reactive power mode.

Abstract: An advantageous method of converting solar energy from a photovoltaic array into alternating current for feeding into the electricity grid is described based on the use of an inventive rotary machine. The inventive rotary machine has a rotor and a set of stator coils which are excited in a first mode by a polyphase current derived from the solar array and simultaneously in a second, orthogonal mode by a polyphase voltage derived from the electricity grid.

Abstract: A power adjusting circuit includes a sensor configured to measure a voltage and a current of the first AC output by an inverter, an AC/DC/AC converter configured to receive the first AC output from the inverter, and a controller configured to convert the first AC output to a second AC output having a desired power factor.

Abstract: Embodiments may include a method of adjusting power in a distributed generation management system. The method may include receiving, by a processor, real-time load requirement data of an energy resources (ER) site. The method may also include receiving, by the processor, real-time energy generation (EG) data from the ER site. The method may further include determining, by the processor, a net power generation at a first level from the real-time load requirement data and the real-time energy generation data. The method may include receiving, by the processor, a first request from a utility to increase or decrease the net power generation from the first level. The method may also include determining a benefit complying with the first request. The method may further include estimating a benefit of not complying with the first request. The method may also include determining whether the determined benefit is greater than the estimated benefit.

Abstract: An electrical system for an automotive vehicle has a plurality of electrical generating machines having field windings energized by pulse width modulated drive signals generated by an external electronic voltage regulator. The pulse width modulated drive signals have a duty cycle determined by the electronic voltage regulator. A controller selects one of electrical generating machines to evaluate for failure and evaluates that electrical generating machine for failure by causing the PWM drive signal for the field windings of that electrical generating machine to be disabled. The controller then determines that this electrical generating machine has failed if the duty cycle for the PWM drive signals has then not been increased by the electronic voltage regulator by a pre-determined amount. The electrical generating machines are either generators or alternators. In an aspect, the PWM drive signals for the plurality of electrical generating machines are out of phase with each other.

Abstract: A double fed induction generator (DFIG) converter method are presented in which rotor side current spikes are attenuated using series-connected damping resistance in response to grid fault occurrences or grid fault clearances.

Abstract: Wind turbine systems and methods are provided. An exemplary system includes a wind driven doubly fed induction generator having a rotor and a stator, the stator providing AC power to a stator bus. The system further includes a power converter coupled to the rotor of the doubly fed induction generator, the power converter providing an output to a line bus, and a transformer coupled to the stator bus. The system further includes a solid-state switch coupled between the stator bus and the transformer.

Abstract: The rotary electrical machine is capable of functioning as a generator and outputs a continuous output voltage (Ub+) that is adjustable by an excitation current. The digital regulator (2) of the machine comprises an excitation current control means (7) and a control loop (6) that includes a device (10) for measurement, by sampling, of the output voltage (Ub+), the measurement device generating a signal sampled at a predetermined first sampling frequency (F1 e). The machine has a bandwidth that is limited by a predetermined first cutoff frequency (F1 c). The measurement device includes an apparatus for oversampling such that the first sampling frequency (F1 e) is greater than twice the first cutoff frequency (F1 c), and the control loop also includes an apparatus (12) for decimating the sampled signal.

Abstract: A power supply system for a motor vehicle includes a generator that includes a rotor having a field coil and a stator having an armature coil; a rectifier that rectifies AC power generated in the armature coil; an excitation control circuit that takes control of a voltage applied to the field coil; a capacitor that is connected to the DC side of the rectifier, and receives and transfers the rectified power; a battery connected to an electric load of the motor vehicle; a DC-DC converter that is connected between the capacitor and the battery and capable of converting unidirectionally or bidirectionally an input DC voltage into any DC voltage; and a selection switch which connects the capacitor or the battery to the excitation control circuit as a power supply source.

Abstract: A method of controlling a generator (110) of an electric drive (104) associated with an engine (102) is provided. The method may determine an operational state of the electric drive (104) based on a speed of the engine (102), and selectively engage one of a map-lookup control scheme (150) and a fixed-theta off control scheme (152) for operating the generator (110) based on the operational state of the electric drive (104).

Abstract: A DC motor assembly (10) with soft starting capability is provided. The assembly (10) comprises a DC motor (12) including an armature (14) and a field winding (16) adapted to be excited separately from the armature; and circuitry configured to controllably increase current flow through the field winding of the DC motor as a function of time during starting of the DC motor.

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: Some embodiments relate to a method of controlling speed of a variable speed generator. The method includes detecting a load of the variable speed generator and determining a target speed for the variable speed generator based on the load supplied by the variable speed generator. The method further includes using a controller to adjust the speed of the variable speed generator based on the target speed. The method may further include correcting the target speed by calculating a correction factor that corrects the target speed based on a voltage produced by the variable speed generator.

Abstract: A dip in the output voltage of a motor-vehicle alternator, owing to a connecting of a load or a change in speed, is compensated with the aid of an alternator regulator which provides a control signal that has a duty factor and increases the excitation current of the motor-vehicle alternator. After the occurrence of the voltage dip, in a first step, the duty factor of the control signal is increased by a differential amount, and in a subsequent second step, the rate of correction is limited. After the occurrence of the voltage dip, parameters describing the instantaneous working point of the motor-vehicle alternator are determined, and in the first step, the differential amount is set as a function of the working point.

Abstract: A generator airgap monitoring system includes a first proximity sensor disposed in a first location of a stator and configured to transmit a first signal representative of a first distance between the first proximity sensor and a plurality of rotor poles of a rotor, and a controller communicatively coupled to the first proximity sensor. The controller is configured to derive a first plurality of instantaneous airgaps based on the first signal and to determine a difference between a first instantaneous airgap of the first plurality of instantaneous airgaps and a second instantaneous airgap of the first plurality of instantaneous airgaps. The first plurality of instantaneous airgaps includes a first plurality of measurements of airgaps between the stator and the plurality of rotor poles when the rotor is rotating. The first instantaneous airgap and the second instantaneous airgaps include measurements for respective rotor poles.

Abstract: The excitation overcurrent detection unit for the doubly-fed electric machine is provided with a function to determine an excitation current magnitude relationship among three phases. The firing pulse is held to on-state or off-state to cause the largest-current phase and the second-largest-current phase to charge the DC capacitor by the operation of diodes. The conduction ratio of the third-largest-current phase or minimum current phase is controlled according to the detected current value to protect against a possible short-circuit across the DC capacitor. When the voltage of the DC capacitor exceeds a preset value, the voltage is suppressed by operating active or passive power devices.

Abstract: A power supply apparatus capable of setting a ripple current to be not more than an acceptable value regardless of an input voltage is obtained. The apparatus calculates switching frequency by a current detected by a current detector so that the switching frequency is set to be low if the current is large and the switching frequency is set to be high if the current is small. The switching frequency is set to be high if the input voltage is high and switching frequency is set to be low if the input voltage is low depending on a voltage inputted to an input terminal; and a switching element is controlled by restricting the switching frequency so that the switching frequency to be set by the current detected by the current detector is not lower than the switching frequency to be set by the input voltage.

Abstract: A method comprises the transmission to a regulator (8) of the alternator of width-modulated pulses (PWM1) exhibiting a duty ratio representative of a setpoint value (Vref) continuously included between a first reference duty ratio (DC1) and a second reference duty ratio (DC2), and the detection of these pulses by the regulator so as to generate the setpoint value. The method also comprises the transmission to the regulator of other width-modulated pulses (PWM2) exhibiting a specific duty ratio (EXOF_R) which is less than the first reference duty ratio (DC1) and ties between a low duty ratio (DCL) and a high duty ratio (DCH), and the detection of these other pulses by the regulator, in a first step, and the generation of an opening signal (EXOF) for a circuit for excitation of the alternator, in a second step, following this latter detection.

Abstract: An electric power generation system and method that permits enhanced power generation efficiency when applied to rotating electric power generation systems is disclosed. The system may be broadly described as generally improving energy generation efficiency by improving the efficiency of electric current extraction from stator coils in many alternator-based electric power generation systems. The system disclosed comprises a number of preferred embodiments, some of which utilize buck-boost converter technologies in conjunction with super-diode excitation/rectification to minimize I2R power losses within rotating power generation system components while at the same time reducing heat losses and thus increasing overall rectification circuitry system reliability.

Abstract: A motor vehicle regulator, including electronic regulation circuits, which can produce an excitation current in accordance with a difference between a set voltage and an output voltage measured at the terminals of an electric battery of the vehicle. The regulation circuits including a programmable signal processing interface for producing a signal, which is representative of the excitation current. The interface receives as input a plurality of signals which are representative of the excitation current. The interface including a device capable of selecting a signal which is representative, from amongst the plurality of representative signals, of the method for applying different forms of processing to the representative signal selected, and a second device for selection of processing to be applied to the representative signal. The representative signal, and the processing to be applied, being selected according to a program provided to the programmable signal interface.

Abstract: A field winding type rotary electric machine includes: a controller; a field current integration portion provided in the controller to calculate an integral value by integrating an excessive field current exceeding a field current threshold; a field current limiting portion provided in the controller and carrying out limiting processing to limit a field current to or below a predetermined value when the integral value reaches an integral value threshold defined as a reference value at or above which the field current is limited; a controller power supply connection switch switched ON and OFF for power feeding to the controller; a controller power supply connection determination portion switching ON and OFF the controller power supply connection switch; and a power feeding ON state maintaining portion maintaining an ON state of the power feeding to the controller from start to end of the limiting processing by the field current limiting portion.

Abstract: Solenoid coils not interlinked by magnet flux of a rotor, increase inductance of a control coil system for controlling generated voltage using little current flow to a switch so no increase in windings of a power coil is needed. A generator with rotor having magnets and stator outside the rotor, have winding coil of the stator connected in series to solenoid coil. A power terminal is between the power and control sides of the solenoid coil and a switch controls flow of current from the power coil to the solenoid coil. By controlling ON/OFF condition of the switch disposed on the DC terminal of a rectifier connected to the solenoid coil in series, the generated voltage is controlled to a voltage set in advance, in response to a detection signal from a sensor detecting the voltage.

Abstract: A fault tolerant electric drive system includes an alternator, a motor controller and an electric motor, wherein the alternator and motor each have a plurality of corresponding independent phase windings, the motor controller having a plurality of independent phase drives corresponding to the phase windings, and a plurality of independent electric drive phases is defined by connecting each corresponding phase winding of the alternator and motor to a corresponding phase drive of the motor controller.

Abstract: A method for starting an electric motor, the motor having a main machine, exciter, and permanent magnet generator (PMG), each having a stator and a rotor, with each rotor mounted to a common shaft, the method comprising starting the main machine in an asynchronous mode by applying a starting current to the stator of the main machine to induce a damper current in a damper winding of the main rotor to generate a starting torque that initiates the rotation of the common shaft, and then running the main machine in synchronous mode by supplying running current from the exciter rotor to the main machine rotor.

Abstract: A power supply apparatus capable of setting a ripple current to be not more than an acceptable value regardless of an input voltage is obtained. The apparatus calculates switching frequency by a current detected by a current detector so that the switching frequency is set to be low if the current is large and the switching frequency is set to be high if the current is small. The switching frequency is set to be high if the input voltage is high and switching frequency is set to be low if the input voltage is low depending on a voltage inputted to an input terminal; and a switching element is controlled by restricting the switching frequency so that the switching frequency to be set by the current detected by the current detector is not lower than the switching frequency to be set by the input voltage.

Abstract: The present invention relates to a method for curtailing electrical power supplied from a wind turbine or a group of wind turbines to an associated power supply grid, the method comprising the steps of determining an available electrical power level from the wind turbine facility and setting a wind speed independent curtailment level. The curtailment level may be a percentage of an actual available electrical power level or a fixed power level. The method further comprises the step of operating the wind turbine facility in such a way that the generated electrical power supplied from the wind turbine facility equals the difference between an actual available electrical power level and the curtailment level. The present invention further relates to a wind turbine facility and a curtailing controller for carrying out the invention.

Abstract: A machine is described that includes an electric drive for propelling the machine along a ground surface. The machine includes an electric power system having a first generator and a second generator. The electric power system also includes a first rectifier coupled to the first generator and having a first direct current (DC) power output and a second rectifier coupled to the second generator and having a second DC power output. Both the first DC output and the second DC output are coupled to the single DC bus, thereby providing an arrangement for the first rectifier and the second rectifier to simultaneously provide power to the single DC bus. A power balancer control receives power commands from both the first and the second ECMs and issues a corrective voltage adjustment to at least one of the first and second ECMs.

Abstract: In a control device for a vehicle AC generator, a voltage control includes target voltage adjusting means for adjusting a target voltage value in response to a target change command from an external control unit and a gradual excitation control circuit that controls an excitation duty to increase according to an excitation duty control characteristic when a vehicle load increases and when the target voltage adjusting means varies the target voltage value to a lower value. The gradual excitation control circuit includes duty characteristic varying means for varying the excitation duty control characteristic. The duty characteristic varying means varies a rate of increase of the excitation duty in a predetermined region of the excitation duty control characteristic in comparison with its other region.

Abstract: Methods and apparatuses for substantially eliminating torque pulsation in a doubly fed induction machine are disclosed. An example method comprises: measuring a stator current of the doubly fed induction machine, measuring a rotor current of the doubly fed induction machine, calculating a total magnetic flux density in an airgap of the doubly fed induction machine, calculating a tangential force density, calculating an electromagnetic torque, repeating the calculation of the electromagnetic torque over one electrical cycle to estimate a torque pulsation, determining a new rotor current that substantially eliminates the torque pulsation by referencing a set of optimal rotor currents in a look-up table, and changing the rotor current in response to the determination. Other embodiments are described and claimed.

Abstract: A vehicle includes a mobile electric power generation system including a mobile power source such as a generator. An external power interface is included to connect to an external electrical power source. An AC electric power distribution bus is included to power electric loads of the vehicle and a power switch device is provided to selectively provide AC electric power on the power distribution bus from one of the respective power sources with a default to select one of the sources whenever it is present.

Abstract: A power supply system for a motor vehicle includes a generator that includes a rotor having a field coil and a stator having an armature coil; a rectifier that rectifies AC power generated in the armature coil; an excitation control circuit that takes control of a voltage applied to the field coil; a capacitor that is connected to the DC side of the rectifier, and receives and transfers the rectified power; a battery connected to an electric load of the motor vehicle; a DC-DC converter that is connected between the capacitor and the battery and capable of converting unidirectionally or bidirectionally an input DC voltage into any DC voltage; and a selection switch which connects the capacitor or the battery to the excitation control circuit as a power supply source.

Abstract: In a portable inverter power generation apparatus, a rectifying circuit converts AC electric power generated by an electric generator into DC electric power, and an inverter circuit converts the DC electric power into AC electric power. A current sensor detects an AC output current from the inverter circuit. In a first case where the AC output current detected by the current sensor increases from a value lower than a first value to a value higher than the first value, a computer sets a target rotational speed to a value lower than a resonance rotational speed at which an engine resonates until the AC output current detected by the current sensor increases to a second value higher than the first value, and sets the target rotational speed to a value higher than the resonance rotational speed when the detected AC output current increases to the second value.

Abstract: A system comprising low cost topology for power converter systems is provided. The system takes advantage of the voltage-boost characteristic of a current source inverter (CSI) and utilizes a PWM CSI as a grid-side converter for power generation systems. Moreover, the generator-side converter employs low-cost devices, such as, but not limited to diode bridge, thyristor bridge, and/or a combination of diodes and thyristors, and accordingly simplifies generator-side converter and control. Further, the system provides a wider range of operation than traditional voltage source converter based topologies that utilize a voltage source inverter (VSI) as the grid-side convertor along with a diode rectifier as the generator-side converter.

Abstract: Methods for controlling a wind power plant that includes a plurality of wind turbines being operatively connected to a plant collector grid a power plant controller, a wind power plant, and a computer program product. The method may include generating an actual power reference signal in response to a determination of the power production of the wind power plant and comparing a desired power reference signal with the actual power reference signal. The method may include either applying a first filter characteristic as part of a generation of a wind turbine power reference if the desired power reference signal exceeds the actual power reference signal, or applying a second filter characteristic as part of the generation of the wind turbine power reference if the actual power reference signal exceeds the desired power reference signal. The first filter characteristic is different from the second filter characteristic.

Abstract: A power generation system includes a generator mechanically coupled to a turbine to generate electrical power. The system includes a fault ride through system having a variable resistor and a variable inductor. The variable resistor is connected in parallel across output terminals of the generator to absorb power from the generator during a grid fault condition, and the variable inductor is connected between an output terminal of the generator and a power grid.

Abstract: A circuit for regulating a DC voltage is provided. The circuit includes: a controllable switch system, a resistor, a first control circuit and a second control circuit. The controllable switch system includes a first terminal, a second terminal, a first control terminal, and a second control terminal. The controllable switch system is configured to establish an electrical connection between the first terminal and the second terminal, if a first control signal applied to the first control terminal satisfies a first criterion or if a second control signal applied to the second control terminal satisfies a second criterion; A method for regulating a DC voltage and an AC-to-AC-converter are described.

Abstract: An electrical supply device includes a set of armature coils which are coupled together in a polygonal mode. The coils are connected to a single bridge rectifier which includes a set of controllable elements allowing switching between a first operating mode in which some of the coils are electrically connected in series and a second operating mode in which all of the coils are electrically connected in parallel. An alternator for a motor vehicle includes the disclosed supply device.

Abstract: In a self-excited generator 1 including an automatic voltage regulator (AVR) 10, a condensive load protection device includes: a field current control driver 21 which is connected to the field winding 6 in series and controlled to be ON/OFF by a drive circuit 23 of the AVR 10 to supply a field current to the field winding 6; and a condensive load protecting rotor short-circuit driver 22 which is connected in parallel to the field winding 6, and supplies a short-circuit current to the field winding 6 by being turned ON, and a bootstrap circuit 30 is connected as a drive power supply of the field current control driver and the condensive load protecting rotor short-circuit driver, and the bootstrap circuit 30 includes a capacitance portion 32 in which charges are accumulated when the field current control driver 21 is ON.

Abstract: A method of controlling a motor is provided. The method may determine a speed of the motor, and engage a soft chopping routine on a first switch and a second switch of each phase if the motor speed is relatively low. The first switch may be driven by a first pulse width modulated PWM signal and the second switch being driven by a second PWM signal. The first and second PWM signals may be alternatingly configured such that at least one of the first switch and the second switch is closed at any point during the distributed soft chopping routine and both the first switch and the second switch are never simultaneously open.

Abstract: A static exciter of a field winding includes a rectifier connected to an electric grid and to the field winding; a unidirectional electronic switch connected in series with the rectifier; a capacitor bank; and a further switch disposed between the unidirectional electronic switch and the capacitor bank. Exciter also includes a control unit connected to the further switch and configured to close the further switch when a grid voltage drops below a first prefixed voltage value so as to connect the capacitor bank to the field winding and configured to open the further switch when the grid voltage exceeds a second prefixed voltage value so as to disconnect the capacitor bank from the field winding and so as to supply energy to the field winding from the capacitor bank for a time period.

Abstract: Some embodiments relate to a standby power system. The standby power system includes a sensor that is adapted to monitor a primary power source which provides power to a load. In some embodiments, the sensor may monitor characteristics of the power supplied by the primary power source 12 that may be used to sense abnormalities. The standby power system further includes a generator that is also adapted to supply power to the load. As an example, the generator may include an internal combustion engine that drives an alternator. The standby power system further includes a generator controller that operates the generator and exchanges data with the sensor. The generator controller predicts a need to supply power to the load based on data received from the sensor. The generator controller then acts to minimize a time to availability of the generator based on the prediction.

Abstract: When a grid disturbance occurs, output power control is performed for each wind turbine so as to reduce fluctuation of a frequency of an output power of the wind turbine at an early stage of the grid disturbance. The output power control is performed for each wind turbine so as to reduce fluctuation of a grid frequency at an interconnection point, in a late stage of the grid disturbance.

Abstract: A method and apparatus is provided to, among other things, supply power to a load under various load conditions. Output voltage transient responses of the system, such as may be caused by transients changes in the load conditions, may be controlled through current transformation on the output in order to correct or impede over-voltage conditions of the transient response.

Abstract: A system for electro-hydrodynamically extracting energy from wind includes an upstream collector that is biased at an electric potential and induces an electric field. An injector introduces a particle into the electric field. The wind drag on the particle is at least partially opposed by a force of the electric field on the particle. A sensor monitors an ambient atmospheric condition, and a controller changes a parameter of the injector in response to a change in the atmospheric condition.

Abstract: Embodiments according to the present invention provide methods and a system for a control approach that effectively maintains the DC link voltage at a constant set value under variable system conditions and keeps the converter operating within an optimal power factor range.

Abstract: Some embodiments relate to an example system for adjusting an exercise schedule of a generator. The system includes the generator and a controller that exercises the generator according to the exercise schedule. The controller modifies the exercise schedule based on generator use. In some of the example embodiments described herein, the controller is a generator controller. Other embodiments relate to a method for adjusting an exercise schedule of a generator. The method includes exercising the generator according to the exercise schedule, and modifying the exercise schedule based on generator use.