Abstract: A method of controlling the output power from a wind energy installation to a utility grid (7) having a specified nominal frequency (fN) is provided, in which the output power (P) is controlled depending on the actual grid frequency (f) in the utility grid (7) such that the output power (P) is reduced when the grid frequency (f) exceeds a predetermined value. The predetermined value is at most two per mill higher than the nominal frequency (fN) of the grid (7) and the output power (P) is reduced as soon as any increase of the grid frequency (f) above the predetermined value is detected.

Abstract: Apparatus, systems, and methods are provided for reducing a potentially damaging high voltage fault condition in an alternator system. The apparatus comprises a motor, a rectifier coupled to the motor, an output node coupled to the rectifier, and a switch coupled between the rectifier and the output node, wherein the switch is a normally “on” switch. The system includes the apparatus implemented into a vehicle comprising an engine to drive the apparatus and a battery coupled to the apparatus, wherein the apparatus provides current to the battery. The method includes the steps of providing current from a rectifier of the alternator to a battery coupled to the rectifier and ceasing to provide current to the battery if a damaging event occurs, wherein the ceasing step comprises the step of switching OFF a normally “on” switch coupled between the rectifier and the battery if a damaging event occurs.

Abstract: An electric generator includes multiple coil sections and switches connected to the multiple coil sections for selectively interconnecting the coil sections in series, or in parallel, or in a series-parallel configuration across first and second power terminals for producing a controlled AC voltage across these power terminals. The electric generator, with its multiple coils and interconnecting switches permitting reconfiguration of the coils, enables systems subjected to widely varying conditions and forces, such as a wave energy converter (WEC), to be operated with increased efficiency. The generator may also include multiple windings which can be selectively interconnected into a wye or a delta configuration to also control the output voltage produced by the generator and increase the efficiency of the power conversion system, particularly at low values of voltage.

Abstract: A brushless exciter for a synchronous generator or motor generally includes a stator and a rotor rotatably disposed within the stator. The rotor has a field winding and a voltage rectifying bridge circuit connected in parallel to the field winding. A plurality of firing circuits are connected the voltage rectifying bridge circuit. The firing circuit is configured to fire a signal at an angle of less than 90° or at an angle greater than 90°. The voltage rectifying bridge circuit rectifies the AC voltage to excite or de-excite the field winding.

Abstract: A stabilizer and synchronous electric power generator system using same that provides both power system damping and excitation limiter functionality. The stabilizer includes a processing unit and a memory storing routines executable by the processing unit. The routines are adapted to receive a voltage signal indicative of a voltage and a current signal indicative of a current output by the generator system, generate, utilizing the voltage and current signals, a power system stabilizer signal for damping oscillations and one or more excitation limiter function signals for controlling excitation level. The routines are also adapted to generate a feedback signal for the generator system by combining the power system stabilizer signal and one or more of the one or more excitation limiter function signals.

Abstract: A method for the operation of a wind energy plant, with a synchronous generator and a superimposition gearbox, which is connected between rotor and generator, and the gear ratio of which is adjusted by a control unit, characterised in that a mode of operation is provided in which the generator is connected to the electric grid, and the generator shaft is uncoupled from the rotor shaft via the superimposition gearbox.

Abstract: A control system that can accommodate the wide variations in the output of a generator, such as a permanent magnet alternator, while providing an output with relatively uniform phase ripple. The control system includes a zero crossing detector and variable ramp generator for generating control signals to a switching rectifier to generate a regulated DC signal.

Abstract: A method and apparatus is disclosed for starting and stopping a generator set that supplies power to a refrigeration system. An ambient temperature sensor is used rather than an in-box sensor in addition to a programmed microprocessor to regulate the operation of the generator. Unnecessary use of the generator is, thereby, limited which contributes to cost, energy and equipment savings and a cleaner environment while ensuring the required in-box temperature is maintained and the quality of perishable goods are not compromised.

Abstract: A starter-generator system supplies a controllable torque to a gas turbine engine, to thereby assist in starting the gas turbine engine, by independently controlling excitation frequency and/or voltage magnitude. The starter-generator includes a multi-phase exciter stator, a rotationally mounted multi-phase exciter rotor, a multi-phase main stator, a rotationally mounted multi-phase main rotor, and an exciter controller. The rotationally mounted multi-phase exciter rotor has a plurality of exciter rotor windings wound thereon that, upon excitation thereof with a rotating electromagnetic exciter flux generated by the exciter stator, have non-rectified excitation currents induced therein.

Abstract: A power generating system provides high voltage AC power and low voltage DC power using a single generator. The generator includes a rotor and a stator that is wound with a first winding and a second winding. The first winding has a greater number of turns than the second winding and generates high voltage AC power in response to the rotating magnetic field created by the rotor. The second winding generates low voltage AC power in response to the rotating magnetic field created by the rotor. The low voltage AC power is converted to low voltage DC power by a rectifier. The low voltage DC power is further controlled by a DC-DC converter to generate controlled DC power. A controller monitors the DC power generated by the DC-DC converter, and generates pulse width modulation signals that are provided to the DC-DC converter, selectively increasing or decreasing the controlled DC power provided by the DC-DC converter.

Abstract: Systems and method for mixing the output of a vehicle alternator throughout any operating temperature range include a first temperature sensor for measuring a first temperature and a second temperature sensor for measuring a first temperature. A first temperature module compares the first temperature with a first temperature reference to determine a first temperature error, and to calculate a first duty cycle reference based on the first temperature error. A second temperature module compares the second temperature with a second temperature reference based on the second temperature error, and to calculate a second duty cycle reference based on the second temperature error. A duty cycle selection module selects the lesser of the first duty cycle reference or the second duty cycle reference as a maximum system duty cycle. A duty cycle control module regulates a field current of the vehicle alternator based on the maximum system duty cycle.

Abstract: In an apparatus, a first detecting unit detects the number of revolutions of a power generator, a second detecting unit detects an output voltage of the power generator, and a third detecting unit detects an output current of the power generator. A torque calculating unit calculates power generation torque based on the detected number of revolutions of the power generator, the detected output voltage, and the detected output current using relationship information. The relationship information represents a relationship between the power generation torque and each of the number of revolutions of the power generator, the output voltage, and the output current.

Abstract: A new methodology for dealing with the Electric-Magnetic Anti-skid Braking System (EMABS) and recycling the regenerating energy on braking is proposed. Developing a dynamic damper which comprising positive and negative type resistors connected in series becomes a fast switch with adaptation, attenuation and fast recovery system properties, is a crucial turnkey. For braking purpose, the most general configuration is to couple the fast switches to the stator and rotor coils in an AC alternator that is driven by the vehicle's wheels or propellers. After performing the dynamic impedance matching in this braking system, the EMABS effect and recycling of the regenerating energy on braking are accordingly obtained.

Abstract: A generator control circuit is provided that includes a first circuit (44) monitoring a generator voltage change rate and producing a first output when the voltage change rate is above a first level, a second circuit (48) monitoring a generator current change rate and producing a second output when the current change rate is above a second level, and a third circuit (13, 28) operatively connected to the first circuit (44) and the second circuit (48) for decreasing a power level supplied to the generator when a plurality of conditions are satisfied, the plurality of conditions including the voltage change rate being above the first level and the current change rate being above the second level. A method of controlling a generator is also disclosed.

Abstract: A method for preventing mechanical oscillation in a wind power plant includes determining wind speed, controlling a generator of the power plant with speed control when the wind speed is below a predefined limit to maintain the rotation speed of the generator below a predefined first limit, detecting the increase of wind speed above the predefined limit, controlling the electric drive of the wind power plant generator to torque control by using a predefined crossover torque in response to the wind speed increasing above a predefined limit, maintaining the crossover torque as the reference torque for the electric drive until the rotation speed of the generator has increased above a predefined second limit, and controlling the electric drive of the wind power plant generator with torque control while the rotation speed of the generator remains above the predefined second limit.

Abstract: A wind turbine braking system including: a wind turbine including turbine blades and a control system; a generator coupled to the turbine blades; a generator converter coupled to the generator and connectable to a utility power grid; at least one dump resistor coupled to the generator and generator converter, and if the utility power grid losses power, the dump resistor applying an electrical load to the generator converter.

Abstract: A system for providing anti-islanding protection of a synchronous machine based distributed generator includes a frequency sensor configured to generate a generator frequency signal, a bandpass filter configured for filtering the generator frequency signal, a governor controller configured for using the filtered frequency signal to generate a power feedback signal, and a governor summation element configured for summing the filtered frequency signal, the power feedback signal, and a reference power to provide an electrical torque signal. Another system includes a voltage sensor configured to generate a generator terminal voltage signal, a feedback power calculator configured for generating a reactive feedback power signal, a bandpass filter configured for filtering the terminal voltage signal, and a PI controller summation element configured for summing the filtered terminal voltage signal, the reactive power feedback signal, and a reference reactive power to provide an error signal.

Abstract: An electric power generation control apparatus has a bridge circuit, a voltage detection circuit, an electric generation control circuit, and an operation mode setting circuit. The bridge circuit has power transistors and diodes through which a field current is supplied to a vehicle alternator driven by a vehicle engine. The voltage detection circuit outputs an instruction signal regarding ON and OFF of supply of the field current so that the output voltage of the vehicle alternator becomes an adjusting voltage. The electric generation control circuit controls the ON and OFF of the power transistors according to the instruction signal from the voltage detection circuit. The operation mode setting circuit selects one of a field wheeling mode and a regenerative mode based on the OFF state of one power transistor, and also selects the regenerative mode when receiving a generation halt instruction form an ECU in the vehicle.

Abstract: A protection system and a protection method are provided for protecting a double fed induction generator and a gearbox during a grid fault. The protection system includes a plurality of controlled impedance devices. Each of the controlled impedance devices is coupled between a respective phase of a stator winding of the double fed induction generator and a respective phase of a grid side converter. The protection system also includes a controller configured for coupling and decoupling impedance in one or more of the plurality of controlled impedance devices in response to changes in at least one of a utility grid voltage and a utility grid current.

Abstract: A control unit assembly is disclosed including a housing, at least one processor to control operation of an engine, and a voltage regulator configured to regulate a voltage of at least one rail of the engine. The at least one processing unit and the voltage regulator reside on a common circuit board.

Abstract: An energy storage system for a motor vehicle is provided, including an electric machine, which can be operated at least as a generator, for generating a generator current; a vehicle electrical system battery, which is connected to the electric machine in parallel; a capacitor unit, which is connected to the electric machine in parallel; and a controller for controlling the electric machine. The controller is configured such that if the vehicle is in the boost or braking operating mode, the battery of the vehicle electrical system is charged with a maximum battery charging current, whereas in all other cases the battery of the vehicle electrical system is charged by a battery charging current that is adjusted as a function of the charge state of the battery of the vehicle electrical system. Therefore, in order to adjust the battery charging current as a function of the charge state of the battery of the vehicle electrical system, three different charge states are considered.

Abstract: An electrical power generation system is provided, and a method of reducing undesired currents therein. The method includes the steps of delivering current via at least one variable frequency switching means, and adjusting a switching frequency of the at least one variable frequency switching means based on the power output of the system. The system may further include an electronic controller having a control algorithm recorded thereon, the control algorithm including means for adjusting the variable frequency switching means based on a power output of the system.

Abstract: In a system, a generator is configured to charge a battery through a charging wire connecting therebetween. A first unit measures a voltage of the battery, and a second unit detects an operating rate of the generator. A third unit determines that the charging wire is broken when the measured battery voltage is lower than a predetermined threshold voltage and the detected operating rate of the generator is lower than a predetermined threshold value.

Abstract: A switching circuit for an electric machine is provided. The switching circuit includes switches for energizing the phase windings of the machine and sensors for driving the state of the switches. The switches are voltage-controlled devices and the sensors are coils.

Abstract: A control apparatus for a vehicle generator includes a switch, a regulator, a fault condition detector, and a PWM signal generator. The switch is selectively turned on and off so as to intermittently excite the generator. The regulator controls on/off operation of the switch so as to bring an output of the generator into agreement with a target value. The fault condition detector detects a fault condition of the generator. The PWM signal generator generates and outputs a PWM signal that has a duty determined as a function of a duty of the on/off operation of the switch and a frequency determined based on if the fault condition of the generator is detected by the fault condition detector. Consequently, the control apparatus can inform an external control apparatus of the duty of the on/off operation of the switch and the fault condition of the generator with the single PWM signal.

Abstract: An apparatus for determining wear in the frictional components of an alternator. Such an apparatus may comprise circuitry configured to count voltage peaks generated by the automotive alternator; circuitry configured to compare the counted voltage peaks against a predetermined standard; and circuitry configured to generate a warning indication when the counted voltage peaks exceeds the predetermined standard. Such an apparatus may comprise comprises circuitry configured to measure a voltage drop across the alternator brushes; circuitry configured to compare the voltage drop against a predetermined voltage drop criterion; and circuitry configured to generate a warning indication if the voltage drop exceeds the predetermined voltage drop criterion.

Abstract: A system for providing anti-islanding protection of a synchronous machine based distributed generator includes a frequency sensor configured to generate a generator frequency signal, a bandpass filter configured for filtering the generator frequency signal, a governor controller configured for using the filtered frequency signal to generate a power feedback signal, and a governor summation element configured for summing the filtered frequency signal, the power feedback signal, and a reference power to provide an electrical torque signal. Another system includes a voltage sensor configured to generate a generator terminal voltage signal, a feedback power calculator configured for generating a reactive feedback power signal, a bandpass filter configured for filtering the terminal voltage signal, and a PI controller summation element configured for summing the filtered terminal voltage signal, the reactive power feedback signal, and a reference reactive power to provide an error signal.

Abstract: An electric power generating system for a vehicle includes a generator having a field coil, a voltage regulator, a temperature sensor for sensing temperature of the voltage regulator, a field current restricting circuit that directly restricts field current if temperature of the voltage regulator becomes higher than a maximum level and a device that prevents temperature of the voltage regulator from further rising without directly restricting field current if temperature of the voltage regulator becomes a warning level that is lower than the maximum level.

Abstract: The vehicle generator regulating apparatus includes a switching device operating to allow a field current to flow into a field coil of the vehicle generator from a vehicle battery when applied with a voltage signal, a drive circuit applying the voltage signal to the switching device when supplied with a control signal, and a control circuit supplying the control signal to the drive circuit when the output voltage is detected to be not above a predetermined voltage. The drive circuit includes a charge pump circuit stepping up a DC voltage supplied from the battery to generate the voltage signal by repeatedly performing a cycle of charging and discharging multiple capacitors in synchronization with an oscillation signal from an oscillator circuit. The drive circuit is configured to lower the frequency of the oscillation signal when the vehicle generator is in a low power output state.

Abstract: An apparatus is provided for detecting a malfunction in an on-vehicle charging system provided with a generator driven by an engine and a battery connected with the generator via a charging line. The apparatus comprises a first control unit controlling a generated condition of the generator and including a first voltage detector detecting a voltage generated by the generator and a second control unit including a second voltage detector detecting a voltage across the battery. The apparatus further comprises a communication device communicating, in the form of digital signals, via a communication line between the first and second control units, information about both the generated voltage and the battery voltage and a malfunction determination unit determining whether or not a malfunction occurs in the charging system on the basis of the communicated information.

Abstract: The present invention relates to a method and to a device for adapting the alternating current generated by a generator (1) and the alternating voltage generated by a generator (1) to a grid (8), whereby the generator (1) has at least one excitation coil (2). The power fed into the grid (8) can be flexibly adapted while entailing low switching losses in that a static frequency converter (9) is employed for the adaptation between the generator (1) and the grid (8), and in that, in order to control the power fed into the grid (8), means (3) are provided with which, on the one hand, the strength of the excitation field generated by the at least one excitation coil (2) is regulated and, on the other hand, the phase angle between the frequency converter voltage and the generator or grid voltage is appropriately controlled.

Abstract: An integrated torsional mode damping method for a current source converter, including a rectifier, an inverter, and a DC link inductor coupled between the rectifier and the inverter, includes sensing a signal representative of torque on a shaft coupled to the inverter or rectifier; using the sensed signal for detecting a presence of a torsional vibration on the shaft; and damping the torsional vibration by modulating active power through the respective inverter or rectifier.

Abstract: A method for powering a pitch motor drive system for at least one DC pitch motor of a wind turbine includes rectifying a voltage using a bridge circuit to thereby supply a DC link voltage to a bridge comprising active switching devices, and utilizing at least one link capacitor to smooth the DC link voltage and act as an energy sink and source for the DC pitch motor or motors.

Abstract: An inverter controlled generator set including: a power supply unit that uses a generator driven by an engine as a power supply to output a DC voltage; an inverter device that converts the output voltage of the power supply unit into an AC voltage; and a rotational speed control unit that controls a rotational speed of the engine so as to be kept at a target rotational speed suitable for a load applied to the inverter device, wherein the rotational speed control unit is comprised so that a settling time when the rotational speed of the engine is caused to converge to the target rotational speed in a state where the load is above a set value is longer than a settling time when the rotational speed is caused to converge to the target rotational speed in a state where the load is below the set value, in order to minimize an operation sound of the engine when the load is intermittently driven.

Abstract: A switching circuit for an electric machine is provided. The switching circuit includes switches for energizing the phase windings of the machine and sensors for driving the state of the switches. The switches are voltage-controlled devices and the sensors are coils.

Abstract: The invention relates to a circuit with a variable rotational speed to be used particularly in a wind power plant, comprising a double fed asynchronous generator (DASM), a crow-bar, an additional resistor (R15) and a converter. In order to meet the requirements of the network provider, whereby a particularly permanent coupling to the network should be ensured so that the wind power plant can start up and stabilize the network during and after medium voltage short circuit in the network, the additional resistor can be regulated with the aid of a fast switch in such a way that the converter can be provisionally disconnected at least partly in case of a short circuit in the network. The rotor current is momentarily assumed by the additional resistor and disconnected after the rotor short circuit current dies out so that the converter can be subsequently connected once again and so that it can supply the desired active short circuit current to the network.

Abstract: The present invention is a generator control system where each generator in the system has an associated controller. Each controller communicates generator data or information with the other controllers in the generator control system. Each of the controllers includes a digital signal processor for analyzing the generator signal from the associated generator and information from the other controllers in the generator control system. The controllers each compare their generator signal with a system average and adjust the associated generator until the generators all supply equal amounts of power to the system.

Abstract: A method of controlling an IPM machine having a salient rotor. Stator terminal signals are measured and rotated to obtain synchronous reference frame current signals. A rotor position is estimated based on an impedance generated using the rotor and included in the current signals. The estimated rotor position is used to control the machine. An alternator-starter system in which this method is used can provide high cranking torque and generation power over a wide speed range while providing operational efficiency.

Abstract: A vehicle AC generator apparatus includes one or more rectifier elements for rectifying a generated AC voltage, and a generator control apparatus which monitors the voltage difference between opposing terminals of a rectifier element, to thereby detect the commencement of electrical generation upon engine starting as the time point at which the polarity of the voltage difference first corresponds to the forward conduction direction of the rectifier element. Controlled parameters such as the current supplied to a charging warning lamp and the excitation current of a generator winding are changed appropriately when generation commencement is detected.

Abstract: A method and an apparatus for providing protection to a generator are disclosed. A reference is determined out of rated capability of the generator. Based on the reference, and field current and output conditions of the generator, there is determined a drop in generator performance due to a temperature condition of the generator. Accounting for the drop in generator performance, operation of the generator may be modified to a generator output limit mode.

Abstract: A power generating system includes a high-frequency alternator, a rectifier, a capacitor in each phase line extending between an output terminal of the alternator and the rectifier, and an auxiliary power supply, providing auxiliary power for use within the power generating system, which is also connected to the output terminals of the alternator.

Abstract: A generator controller (4) is provided which is able to detect and respond to failure of a generator output voltage sensor, whilst being able to distinguish voltage sensor failure from output voltage collapse due to the presence of an overload or short circuit condition. The presence of a voltage sensor failure is indicated by the measured output voltage being below a first voltage threshold whilst the output current is also below a current threshold.

Abstract: A fault handling algorithm processes a plurality of fault status signals from a sputtering system in a period of time to generate at least one command signal for affecting the operation of a power generator.

Abstract: An apparatus for the improvement of AC waveform comprising means for applying a demand input waveform at an input of a circuit for power conditioning (including an inverter PWMVC or BBHCC) that is operable to provide an output waveform at an output; a feedback loop between the input and output, the feedback loop including means for sampling the output waveform (ADC1), means for subtracting a required waveform (RW) from the output waveform to produce an error waveform, means for processing the error waveform in a pre-defined manner to produce a processed error waveform (Clip1, Disc1, Att1), means for adding or subtracting the processed error waveform from Th. demand waveform to produce a revised demand waveform, and means for applying the revised demand waveform to the input of the power conditioning circuit at a subsequent time as an input demand waveform to produce a new AC output waveform at the output.

Abstract: A method and apparatus for welding with an engine driven inverter power supply includes generating an ac output with an engine and generator. The output is rectified and inverted to provide an ac inverter output. The engine is controlled using feedback indicative of a welding output operating parameter. The feedback may also be taken from the inverter or generator, and the generator may be controlled instead of or in addition to the engine. Engine parameters that may be controlled include engine speed, selecting between an idle speed and a run speed, a throttle position, a fuel pump, an injection timer, a fuel to air ratio, fuel consumption and ignition timing. Another aspect of the invention is having the feedback be responsive to one or more of the welding current, welding voltage, welding power, or functions thereof. The feedback may be responsive to the current, voltage, power, ripple and functions thereof.

Abstract: A variable speed wind turbine is disclosed comprising a turbine rotor that drives a doubly-fed induction generator, a matrix converter which converts variable frequency output into constant frequency output, and a control unit and a protection circuit for the matrix converter. Power is circulated in the system allowing for sensorless detection of rotor position and better output ratios of power from the system.

Abstract: An excessive voltage protection system for a variable frequency generating system detects single point failures in a generator control unit and prevents excessive voltages at a point of regulation (POR) in the system. The generator control unit is designed to detect failures, such as a loss of three-phase sensing capability, switch failure in the exciter drive circuit, and/or exciter current loop failure. If a failure occurs, the generator control unit stops operation of the exciter drive circuit, preventing the voltage at the POR from rising to undesirable levels.

Abstract: A system and a method for thermally protecting a high output vehicle alternator are provided. The high output vehicle alternator includes a duty cycle control system. The duty cycle control system includes an alternator temperature signal generator and an alternator rotor speed signal generator in communication with an alternator having a speed limit and a temperature limit. The duty cycle control system regulates the field current supplied to the alternator based on the temperature and rotor speed signals.

Abstract: An apparatus of the invention controls the air-fuel ratio in response to the stable output of an oxygen sensor. When a system protector 138 detects a disorder in a power network, it outputs failure signal. A connection relay 135 is opened in response to the failure signal to release connection of a generator to the power network to release load. When the failure signal is not detected, a load determination section 41 urges a proportional valve controller 40 and the controller 40 drives a valve 35 corresponding to the oxygen density to perform a control of the air-fuel ratio. The load determination section 41 determines that the load is released by the failure signal to send a notification of no load to the controller 40. The controller 40 stops the control of the air-fuel ratio based on the oxygen density in response to this notification.

Abstract: A control apparatus and a control method of an on-vehicle dynamo-electric machine 1 are provided for efficiently controlling functions as a starter-motor and as a charging generator. In case that the dynamo-electric machine 1 acts as a charging generator, when a rotation speed of the dynamo-electric machine 1 is not higher than a predetermined value, a power is generated by applying a compensation current from and inverter to an armature coil 3 for phase control. On the other hand, when a rotation speed of the dynamo-electric machine 1 is not lower than a predetermined value, operation of the inverter is stopped. Thus, controlling a current applied to a field coil 4 by a field coil current control means 5 generates a predetermined target voltage.