Abstract: An inverter system is configured to mitigate oscillation of a rotary system that drives a generator or electric machine. A torque damping module is configured to receive a commanded torque or an observed torque and to generate a commanded compensating torque to dampen any mechanical oscillation or resonance of the rotary system based on the observed rotational speed of the generator. The torque damping module further comprises a digital filter of order greater than one, a gain adjuster and a limiter.

Abstract: A grid-forming wind turbine control method for a diode rectifier unit-based offshore wind power transmission system. A control system for controlling a grid-side converter has a three-layered structure, where a first layer is a combination of an active power controller and a reactive power controller; a second layer is a voltage controller; and a third layer is a current controller. The actual reactive power is represented by a per-unit value of a capacity of a corresponding wind turbine unit. The wind turbine units have the same reactive-power reference value, which is constant and does not change with time. The reactive power controllers of all wind turbine units have the same structure and parameters.

Abstract: Methods include, in response to a line frequency variation of a power grid, adjusting a voltage setpoint of a voltage regulator coupled to the power grid at a grid edge to maintain a voltage at the grid edge, wherein the adjusting the regulated voltage setpoint is configured to reduce the line frequency variation to stabilize the line frequency of the power grid. Apparatus include a voltage regulator configured to couple to a power grid at a grid edge and to maintain a voltage at the grid edge, wherein the voltage regulator is further configured to adjust a voltage setpoint of a voltage regulator in response to a line frequency variation of the power grid to reduce the line frequency variation and stabilize the line frequency of the power grid.

Abstract: A method for detecting an islanding condition of a grid connected energy conversion system and related DC/AC converter apparatus to optimize performance in terms of preservation of the power quality, provide synchronized frequency perturbation for all the inverters of a plant, provide shut down capability within the time requested by utilities and safety standards and provide immunity to grid frequency fluctuations.

Abstract: A power source includes: a generator; a turbine device that drives and rotates the generator; and a control device that: monitors a rotation speed of the generator; calculates a first adjusting power instruction value corresponding to a deviation between a reference value and an observed value of the rotation speed of the generator; acquires an adjusting power amplification coefficient from an external device; calculates a second adjusting power instruction value indicating a degree of increase of the adjusting power, based on the first adjusting power instruction value and the adjusting power amplification coefficient; amplifies the adjusting power based on the second adjusting power instruction value; and outputs the amplified adjusting power to the turbine device to adjust power supply from the generator and reduces fluctuation of frequency in a power transmission and distribution system.

Abstract: A hierarchical power control system associated with a cloud server includes a first microgrid cell, a second microgrid cell, a third microgrid cell, a middleware server, and an integrated control system. The first microgrid cell includes a first energy storage system (ESS) having an uninterruptible power supply (UPS) structure and a first load having a power state managed by the first energy storage system (ESS). The second microgrid cell includes a second load and a second energy storage system (ESS) for managing a power state of the second load. The third microgrid cell includes a third load. The middleware server communicates with the first to third microgrid cells. The integrated control system receives power supply-demand state information of the first to third microgrid cells through the middleware server, and establishes an integrated operation schedule based on the received power supply-demand state information of the first to third microgrid cells.

Abstract: A synchronous machine system comprising a synchronous motor including a stator, stator winding, rotor, and field winding; an AC power supply circuit structured to transmit current to or from the stator winding of the synchronous motor at a controlled frequency and transmit current to or from a power source at a controlled frequency; a DC exciter unit structured to receive power from a power source, convert the received power to DC power at a desired voltage, and supply the converted power across a DC bus to the field winding of the synchronous motor; and an energy storage circuit coupled to the DC bus of the DC exciter unit having at least one ultracapacitor, and structured to receive power from a power source, to charge the ultracapacitor, and to provide power to the field winding of the synchronous motor following a power failure.

Abstract: Embodiments of a welding power supply include an engine adapted to drive a generator to produce a first power and a energy storage device adapted to discharge energy to produce a second power. The welding power supply also includes control circuitry adapted to detect a commanded output. The control circuitry is adapted to meet the commanded output by controlling access to power from the energy storage device to produce the second power when the commanded output is below a first predetermined load level. The control circuitry is further adapted to meet the commanded output by controlling access to power from the engine and the energy storage device to produce the first power and the second power when the commanded output is above a second predetermined load level.

Abstract: A control system for a power source is disclosed. The control system includes a first sensor module and a second sensor module to generate signals indicative of an ambient condition of the power source and an operating parameter of an engine of the power source, respectively. The control system further includes a controller that receives signals indicative of the ambient condition and the engine operating parameter and determines a first power output based on the ambient condition and a second power output based on the engine operating parameter. A final power output is further determined based on the first and second power outputs, which is further compared with a predetermined power output of the engine. A power conversion device that is coupled to the engine is further controlled to regulate a power output of the power source based on the comparison between the final and predetermined power outputs.

Abstract: A power supply system comprising a power source apparatus connected at a junction point P1 to a system power source line L0 provided between a system power source and a load device, and a power source apparatus connected at a junction point P2 to the system power source line L0. The power supply system includes a current sensor CT2-1 provided on the system power source line (L0) between the system power source and the junction point P1, a current sensor CT2-2 provided on the power source apparatus power source line L1 between the power source apparatus and the junction point P1, and a current sensor CT2-3 provided on the system power source line L0 between the junction point P1 and the junction point P2. The power source apparatus controls the output of power from the power source apparatus, on the basis of the outputs from current sensors CT2-1, CT2-2, CT2-3.

Abstract: A power system stabilizing device includes an arithmetic unit that constructs a system model by collecting various kinds of system information, calculates a transient stability under an assumed accident condition beforehand, and selects, for each assumed accident in advance, a target solar power generator for shutdown and a target power generator to be disconnected to stabilize a power system, and a control unit that shutdowns the shutdown target solar power generator and disconnects the disconnection target power generator from the power system which are selected by the arithmetic unit when a system accident occurs.

Abstract: An electro-mechanical kinetic energy storage device includes an input port, an output port, and a tertiary port separate from and magnetically coupled to the input port and the output port. The input port is configured to receive a first input electrical energy from a first electrical source for inducing mechanical energy into the electro-mechanical kinetic energy storage device. The output port is configured output a first converted electrical energy to a first load in which the outputted electrical energy is generated from the induced mechanical energy. The tertiary port is configured to receive a second input electrical energy from a second electrical source for inducing the mechanical energy, and output a second converted electrical energy to a second load, the second converted electrical energy generated from the induced mechanical energy.

Abstract: A control system for a vehicle operable to implement a speed control function, the control system being operable to: receive an input of a target speed at which the vehicle is intended to travel; determine an instantaneous value of a primary target speed torque parameter corresponding to an amount of torque that should be developed at a given position in a powertrain in order to control the vehicle to travel at the target speed; and filter by means of filter means a value of a torque parameter input thereto to generate a filtered torque parameter value, the system being operable to command the powertrain to develop at said position an amount of torque corresponding to the filtered torque parameter value, wherein the system is operable to input to the filter means a secondary target speed torque parameter value determined in dependence on the primary target speed torque parameter value and a current value of filtered torque parameter generated by the filter means.

Abstract: An electromechanical energy conversion system includes a variable capacitor, an electronic charging/discharging unit and a power source/sink; the power source/sink being coupled to the electronic charging/discharging unit which is coupled to the variable capacitor; the variable capacitor including first and second electrodes that are separated by an intermediate medium providing a gap distance therebetween; the gap distance being adjustable between a minimal distance and a maximal distance as a function of an externally applied mechanical force; the electronic charging/discharging unit being arranged for charging the variable capacitor from the power source/sink at substantially a state of the variable capacitor when the gap distance is minimal and the area of the elastically deformed body maximal, and for discharging the variable capacitor to the power source/sink at substantially a state of the variable capacitor when the gap distance is maximal and the area of the elastically deformed body minimal.

Abstract: The present invention provides an auxiliary excitation winding set to be installed at the rotary part of the electric machine (104) composed of a rotary part of the permanent magnetic electric machine or a rotary part of the reluctance electric machine of the switched DC electric machine with conduction ring and brush (1000), and an electric conductive annular brush device (107) is served as an interface for transmitting the electric power, thereby inputting the excitation electric power to the auxiliary excitation winding set; and through controlling the value and the polarity of excitation voltage and current, the magnetic pole of the rotary part of magnet-motive electric machine (104) of the switched DC electric machine with conduction ring and brush (1000) can be performed with the excitation effect of auxiliary excitation or differential excitation or auxiliary compound excitation or differential compound excitation.

Abstract: The present invention relates to a multi-set switched DC electric machine having conduction ring and brush and having its rotary part of electric machine being installed with an auxiliary excitation winding set, for being connected in series with a magnetic field winding set of electric machine of another electric machine through the auxiliary excitation winding set installed on the rotary part of electric machine, such that the excitation can be variable through altering the current of the magnetic field winding set of electric machine of the another electric machine thereby changing the operational characteristic of the electric machine.

Abstract: Controlling a shaft of a turbine generator, wherein the turbine generator includes a static excitation system and wherein the shaft is being driven in a first rotational direction at a predetermined speed. Controlling the shaft includes detecting a torsional oscillation of the shaft, calculating a control signal based on the torsional oscillation, and using the control signal, controlling an amount of power drawn by the static excitation system from the turbine generator.

Abstract: A power generation park is provided including a power output for providing electrical output power to an electricity network. A power generation device includes a converter device configured for receiving input power from a power generator and providing, in response hereto, the electrical output power to the power output. The power generation park further includes a controller configured for receiving an oscillation indicating signal indicative of a power oscillation in the electricity network, the controller further configured for providing a damping control signal in response to the oscillation indicating signal, the converter device configured for modulating the electrical output power in response to the damping control signal so as to damp the power oscillation in the electricity network.

Abstract: A method for controlling a motor vehicle alternator, in which an error value, resulting from the comparison between the voltage produced by the alternator and a set value, is processed in a filtering means by applying a transfer function, which determines a gain to be associated with the error value on the basis of the rotational frequency of the alternator, in order to control the adjustment of the field current allowed by the alternator. The transfer function of the filtering means is modified on the basis of the rotational speed of the alternator by attenuating the gain over a given frequency range when the rotational speed decreases.

Abstract: A power supply system configured to couple to a power distribution bus of a marine vessel and to power a plurality of electric motors coupled to the power distribution bus. The power supply system includes a generator configured to generate electric power and a control system coupled to the generator and configured to control the output voltage of the generator based on a voltage setpoint. The control system includes a measuring unit configured to measure a parameter of the electric power generated by the generator and a control unit configured to control the voltage setpoint for the output voltage of the generator based on the measured parameter.

Abstract: A control system for increasing the damping of a resonant mode of a rotor drive train is provided. A control loop is introduced in parallel with the free turbine speed governing control loop. The control loop receives a feedback signal from the free turbine and rotor drive train, the feedback signal representative of the free turbine speed. The control loop extracts the resonant component from the feedback signal to generate a resonant signal containing the resonant component and estimates a derivative of the free turbine speed from the resonant signal. The control loop then outputs a request for damping the resonant mode on the basis of the derivative. A narrow-band reject filter is introduced in the free turbine speed governing loop to filter out the resonant component from the feedback signal, thereby ensuring that the free turbine speed governing loop does not interfere with the control loop.

Abstract: A control system for increasing the damping of a resonant mode of a rotor drive train is provided. A control loop is introduced in parallel with the free turbine speed governing control loop. The control loop receives a feedback signal from the free turbine and rotor drive train, the feedback signal representative of the free turbine speed. The control loop extracts the resonant component from the feedback signal to generate a resonant signal containing the resonant component and estimates a derivative of the free turbine speed from the resonant signal. The control loop then outputs a request for damping the resonant mode on the basis of the derivative. A narrow-band reject filter is introduced in the free turbine speed governing loop to filter out the resonant component from the feedback signal, thereby ensuring that the free turbine speed governing loop does not interfere with the control loop.

Abstract: A method for damping torsional oscillations in a drive train component, in particular a gearbox, in particular in a power production plant, includes adjusting a load on the output side in the drive train as a function of a difference between a rotational speed of an input shaft of the drive train component and a rotational speed of an output shaft of the drive train component.

Abstract: A power supply apparatus includes: an AC generator including an AC generating section, and a rectifier for rectifying an AC voltage generated in the AC generating section, and outputting a DC voltage; and a DC/DC converter for converting the output voltage of the rectifier into a DC voltage having a different voltage value, wherein the output voltage of the rectifier is set to be larger than the output voltage of the DC/DC converter in accordance with the rotation speed of the AC generating section and the amount of power supply to an electrical load connected to the DC/DC converter, and is stepped down and outputted by using the DC/DC converter. The power supply apparatus is capable of increasing an output power efficiently.

Abstract: A control unit of a system stabilizing device uses a fluctuation detecting block (70A) to determine fluctuation components included in the active component and reactive component currents of a system current. The fluctuation detecting block (70A) is composed of a low-pass filter (71) for noise removal having first order lag characteristics with a time constant of T1, a low-pass filter (72) for setting a fluctuation detection time having first order lag characteristics with a time constant of T2, a subtracter (73) which performs subtraction between the output signals of the filter (71) and the filter (72) and outputs the difference, an amplifier (74) for amplifying the output of the subtracter (73), a rating limiter (75) for limiting the output of the amplifier, and an overcompensation inhibiting unit (200) which changes T4 to a smaller value when the rating limiter (75) performs a limiter action.

Abstract: A method and arrangement for controlling a doubly-fed induction machine by a frequency converter including a rotor side converter (INU) connected to a rotor circuit of a doubly-fed induction machine (DFIG) and having a control system with rotor flux as a feedback variable, a grid side converter (ISU) connected to an AC power network, and a direct voltage intermediate circuit (DC) connected between the rotor side converter (INU) and the grid side converter (ISU). The method includes forming a rotor flux reference (?r,ref), forming a damping signal (?ref,D), summing the damping signal and the rotor flux reference for obtaining a modified rotor flux reference (?ref), and feeding the modified rotor flux reference to a controller of the rotor side converter (INU) for damping sub-synchronous resonances.

Abstract: An anti-islanding implementation that introduces a small, continuously varying phase shift pattern in the output current of an inverter. In grid-connected mode, this phase shift pattern has no impact on the frequency of the inverter's output voltage. However, when islanded, the phase shift will cause the voltage frequency to deviate from nominal. Changes in the output current phase thus correlate well with the voltage frequency, so a covariance index is used to detect an islanding configuration. When this index exceeds a threshold, a larger phase shift pattern is introduced in the output current, large enough to cause the voltage frequency to fall outside the inverter's trip protection window without compromising the inverter's power quality yet ensuring reliable tripping of the inverter.

Abstract: A fault-ride-through method is provided. The method includes detecting a voltage dip on a power line transmitting electric power. If a voltage dip is detected, the method includes reducing an active current and/or an active power to a specific value, which active current and/or active power is fed by a power generating unit at a feeding point into a power network having a plurality of power lines. Further, a converter of a power generating unit is provided, that is capable of implementing the fault-ride-through method. The power generating unit may be a part of a wind turbine in a wind farm.

Abstract: A control device of a wind turbine generator capable of controlling an active power based on an instruction value, includes a measurement means configured to measure a frequency of a utility grid. The instruction value for controlling the active power is generated to a direction suppressing a variation of the frequency of the utility grid based on conversion information which indicates a predetermined relation between the variation of the frequency and the instruction value when the variation of the frequency of the utility grid measured by the measurement means exceeds a predetermined standard. A wind turbine generator which controls suppression of a disturbance of a grid in its initial stage is realized.

Abstract: A power system stabilizer includes: a sensor configured for sensing a signal representative of electromechanical oscillations of the power system; a controller configured for using the sensed signal for generating control signals for damping the electromechanical oscillations; and a damper including a damping converter and a resistor coupled to the damping converter, the damping converter being coupled to the power system through a power bus, the damping converter configured for using the control signals for damping the electro-mechanical oscillations.

Abstract: Torsional oscillation of a shaft in a swing drive system of an excavator is minimized by monitoring torsional strain of the shaft. An electric motor provides torque to the shaft in response to a drive signal provided by a converter. A compensation circuit produces a compensation signal as a function of torsional strain of the shaft. A field excitation circuit or regulator powers a converter as a function of the compensation signal such that a counter torque is provided to the shaft and torsional oscillation of the shaft is reduced.

Abstract: An electric load damper assembly includes a synchronous generator operable to provide a plurality of phases of electrical output in response to a mechanical input from a rotating shaft. An electric load damper includes a phase leg for each of the plurality of phases. Each phase leg includes a resistive load, a snubber and at least one solid state switch. The at least one solid state switch is in parallel with the snubber, and the at least one solid state switch and snubber are collectively in series with the resistive load. A controller is operable to receive a signal indicative of a rotational speed oscillation of the synchronous generator, and is operable to selectively reduce a torsional oscillation of the shaft by diverting electrical current from the synchronous generator through the resistive load of each of the plurality of phases in response to the signal exceeding a predefined threshold.

Abstract: The control device detects the B-terminal voltage by a B-terminal voltage detection section. When an abnormal voltage detection section detects that a voltage value of the detected B-terminal voltage is equal to or higher than a predetermined voltage value, all switching elements of the negative pole-side arm in a power conversion section are brought into conduction by a negative pole-side arm short-circuiting section, whereas all switching elements of a positive pole-side arm are interrupted. In addition, a field current is limited to zero or to a limit value by a field current control section.

Abstract: Methods and systems for minimizing power loss in generator are disclosed, including providing one or more operating parameters for a generator, and determining an optimal field power and an optimal phase angle, where the optimal field power and the optimal phase angle substantially minimize a power loss in operating the generator at the one or more operating parameters.

Abstract: Provided is an alternator controller that sets a target current value based on a target voltage as a control reference of an alternator mounted on a vehicle, and controls the alternator based on the set target current value. The alternator controller includes a filter processing unit that performs filter processing of a target power generation torque as a conversion physical amount used until the target current value is set from the target voltage. The filter processing unit performs a filter processing that attenuates or removes a frequency component f of the pitch resonance frequency of the vehicle among the waveforms of the target power generation torque. Thus, it is possible to surely suppress fluctuations of a vehicle behavior attributed to torque fluctuations of an alternator load torque.

Abstract: A voltage control apparatus for an electric generator includes a load response controller and a voltage response controller. The electric generator includes a field winding and is driven by an engine of a motor vehicle. When the output voltage of the generator decreases below a threshold voltage upon the application of an electrical load, the rotational speed of the engine fluctuates to repeatedly increase and decrease until it is stabilized. During the time periods in which the rotational speed of the engine decreases, field current supplied to the field winding of the generator is gradually increased under a load response control performed by the load response controller. During the time periods in which the rotational speed of the engine increases, the field current is gradually increased under a voltage response control by the voltage response controller.

Abstract: A method and apparatus for operating a wind energy plant with a rotor blade control, a torque control and a control unit. A power limited mode of operation presets a desired value for the fed power, which is smaller than the rated value for the plant. On a threshold rotational speed, the torque is lowered through the torque control such that the preset desired value for the power is not exceeded. The threshold rotational speed, depending on the preset desired value for the moment (Mdesired), is set to a value smaller than the rated value for the rotational speed.

Abstract: A control and power module for a rotating electrical machine comprising a power circuit containing a number of branches, and a control circuit designed for controlling the power circuit when the machine operates in a nominal mode. The inventive module is characterized in that the control circuit is also designed for monitoring an output voltage from the power circuit and blocking at least one branch of the power circuit in a conduction state when the output voltage reaches an at least first threshold value so that the machine functions in a degraded mode. The invention is for use in an alternator starter.

Abstract: A system and method of use for self-tuning a PID controller utilized with an exciter and generator is disclosed. The system includes a power source, an exciter electrically connected to the power source, a generator that is electrically energized by the exciter, and a processor that provides a PID controller that calculates an estimated exciter time constant and an estimated generator time constant using particle swarm optimization (“PSO”) to control exciter field voltage. The particle swarm optimization (“PSO”) technique includes increasing the voltage reference by a predetermined percentage over a predetermined time period, initializing each particle position of exciter time constant and generator time constant, calculating generator voltage, performing a fitness evaluation and then obtaining and updating best values. This is followed by repeating the steps of determining the generator voltage, the fitness evaluation, and the best values over a predetermined number of iterations.

Abstract: An electric generator is operated under conditions in which rapid off-loading may occur. A generator control unit (GCU) employs a detector to detect rates of change of output of the generator. In response to a rapid change of output, e.g. an off-loading, an overvoltage protection system is activated. Excess energy stored is an excited winding is directed into an impedance circuit thus precluding overvoltage that may have been produced by the excess energy.

Abstract: A device for controlling vehicle power generation that controls duty cycle of an excitation winding in a vehicle power generator and controls an output voltage from the vehicle power generator to a predetermined value includes a power generation controlling circuit that, when the output voltage from the vehicle power generator is less than the predetermined value, gradually increases the value of a gradual excitation duty and gradually increases the excitation current, the gradual excitation duty being a limit value for increasing and decreasing an excitation drive duty intermittently controlling the electrification of the excitation winding, and in an opposite situation, gradually decreases a value of the excitation drive duty and gradually decreases the excitation current. The power generation controlling circuit changes the rate at which the value of the gradual excitation duty is decreased.

Abstract: A generator having a field coil L, and an SW1 control circuit 2 for controlling field current flowing through the field coil L. When a generating operation of the generator is to be ended, a switch 1 SW1 is turned off to interrupt the field current flowing through the field coil L, and a switch 2 SW2 is turned off to allow the field current remaining the field coil L to the current path including a resistance element 1 with a resistance element capable of quickly attenuating the field current.

Abstract: An electric power generation control apparatus for a vehicle alternator mounted on a motor vehicle performs one of a constant output voltage control a constant torque control and a constant exciting current control in order to suppress a hunting phenomenon of the vehicle alternator. First of all, the electric power generation control apparatus performs the constant output voltage control when a rotation speed is within an idling rotation speed range or a periodic change of the rotation speed is not less than a predetermined value. After completion of the constant output voltage control, when judging that the idle hunting phenomenon is not adequately suppressed, the electric power generation control apparatus performs one of the constant torque control and the constant exciting current control.

Abstract: A resistive torsional mode damping system for a shaft of a machine includes: a sensor configured for sensing a signal representative of torque on the shaft; a controller configured for using the sensed signal for detecting a presence of a torsional vibration on the shaft corresponding to a natural frequency of the shaft and for generating control signals for damping the torsional vibration; and a damper including a damping converter and resistor coupled to a DC output of the damping converter, the damping converter being coupled to the machine through a power bus and having a power rating on the order of less than or equal to about five percent of a nominal power of the machine.

Abstract: This invention discloses a vehicle electrical system voltage regulator with improved electrical protection and warning means that discerns and responds to regulator, generator, or vehicle electrical system operation and malfunctions. The regulator includes monitoring, control, and protection circuits with a phase signal monitor, a field switching circuit that operates the field coil in response to electrical power demands, and a field enable switch in series with the field regulating switch. The phase monitor and protection circuit ascertains and transmits generator rotational motion for use by the monitoring and control circuit in discerning the various operating conditions. The monitoring and control circuit operates on the field switching circuit to meet the electrical power demands and provide multi level fault protection to include field switching circuit reconfiguration to continue operating under various fault conditions.

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: The vehicle generator includes a rotor around which a field winding is wound, a stator around which an armature winding is wound, a rectifier rectifying an AC voltage induced in the armature winding to generate a DC output current. The rectifier has a plurality of rectifying elements mounted to a current path section thereof, the DC output current flowing through the current path section to reach an output terminal of the vehicle generator. The vehicle generator further includes a first voltage detector circuit detecting a voltage difference between two points of the current path section located along a direction in which the output current flows, and an output current calculating circuit calculating a value of the output current on the basis of the voltage difference detected by the first voltage detector circuit and a resistance value between the two points of the current path section.

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: The vehicle power-generation control unit has a first function enabled when a control signal received from outside designates a first mode to control an exciting current such that an output power of a vehicle generator is kept at a value specified by the control signal, a second function enabled when the control signal designates a second mode to control the exciting current such that a generation voltage of the vehicle generator is kept at a target voltage specified by the control signal, and a third function enabled when the control signal designates the first mode to monitor whether or not the generation voltage is in a predetermined voltage range and to disable the first function in order to control the exciting current such that the generation voltage is kept at a preset voltage upon detecting that the generation voltage is out of the predetermined voltage range.

Abstract: A power conditioner 10 is provided with a maximum power follow-up control portion 12 for setting a DC operating voltage of a power converter 11, which converts output power of a power generator 2 into AC power, for making a power point corresponding to the output level of the power generator follow up with a maximum power point, and comprises an approximate function memory 25 for storing approximate functions related to the maximum power point, a follow-up control portion 34 for making the present power point reach proximate of the maximum power point on the basis of the approximate function, and a hill-climbing method follow-up control portion 35 for making the present power point reach the maximum power point by using a hill-climbing method when the present power point has reached proximate of the maximum power point.