Abstract: A control device measures a voltage drop across a conductor in a generator to determine and control the total generator output current. A temperature of the conductor is also measured to improve the accuracy. The control device may further improve on the accuracy by compensating for the electrical current through a field coil that may power the generator. The control device may be used in combination with a generator in a vehicle electrical system. Other system parameters may be monitored to improve on the system monitoring, diagnostics, and control. The generator may include a conductor comprising a process-controlled geometric shape.

Abstract: A Frequency-On-Demand type voltage regulator firstly has its power output circuit configured as a resettable monostable multivibrator that provides (1) a stable time-base that serves as an internal “OFF”-period reference; preferably also with (2) short-circuit protection to the output power transistor; and (3) a pulse train with sharply defined “ON” and “OFF” transitions as the result of the interaction between the Output and Input Stages of the Power Output Circuit through a first AC Feedback Network. The “ON” and “OFF” transitions are preferably rounded-off. Secondly, yet another, second, AC feedback network is added between the Output Stage of the Power Output Circuit and the Error-Detector/Voltage Divider Stage of the Frequency-On-Demand type voltage regulator.

Abstract: A double alternator system includes a first brushless winding assembly to generate a first electrical voltage, a second winding assembly to generate a second electrical voltage, a rotatable shaft common to the first brushless winding assembly and second winding assembly to cause generation of a first electrical voltage and second electrical voltage upon rotation of the shaft, and a housing in which the winding assemblies are disposed and through which the first and second electrical voltages are carried to respective first and second electrical output contacts.

Abstract: A control apparatus for controlling an exciting current of a field winding type dynamo-electric machine having an exciting winding so as to obtain a demanded output thereof comprises an exciting current detecting circuit being configured to detect an exciting current of the field winding type dynamo-electric machine, a rotation speed detecting circuit being configured to detect a rotation speed of a rotor of the field winding type dynamo-electric machine, an output estimating circuit being configured to estimate an output of the field winding type dynamo-electric machine, an exciting current control circuit being configured to correct the exciting current of the field winding type dynamo-electric machine so as to obtain the demanded output and to supply the corrected exciting current to an exciting winding of the field winding type dynamo-electric machine considering a multi-valued functionality of the output of the field winding type dynamo-electric machine with respect to the exciting current.

Abstract: Methods, devices, and systems are disclosed for a power generator system. A power generator system ay comprise at least one control device including control logic. The at least one control device may be configured to receive at least one control signal and output an upper reference voltage and lower reference voltage. The at least one control device may be further configured to vary a magnitude of at least one of the upper reference voltage and the lower reference voltage. The power generator system may also comprise a power generator operably coupled to the at least one control device and configured to receive the first reference voltage and the second reference voltage. The power generator may be further configured to output a voltage that greater than or equal to the first reference voltage and less than or equal to the second reference voltage.

Abstract: The vehicle-use generator includes a rotor rotatably mounted on a shaft and having a field coil wound therearound, a stator having stator winding wound therearound and fixedly disposed so as to form a gap with the rotor, a cooling fan mounted to the rotor, a pulley belt-driven by a vehicle engine and coupled to the shaft through an overrunning clutch provided therein, and a power generation control device controlling an excitation current flowing into the field coil. The overrunning clutch is configured to idle when a rotational speed of the pulley is lower than a rotational speed of the rotor to inhibit torque transmission from the pulley to the rotor, and the power generation control device is configured to forcibly increase the excitation current on a temporary basis when an upshift operation of a transmission of the vehicle is performed.

Abstract: A hybrid voltage regulator controls the voltage of three phases of alternating electricity produced by an alternator. A digital voltage regulator produces an average of the RMS voltage for each phase and produces an error value based on a ratio of the voltage to the frequency of the alternating electricity. The RMS voltage average and the error value are used to modify a voltage command designating a desired voltage level. The modified voltage command is processed by an analog voltage regulator that rectifies the alternator output voltage which then is averaged over an period of time. The resultant average voltage value is utilized to modify the voltage command to produce a regulated voltage command that determines a level of current to apply to excite the alternator.

Abstract: A method for protecting voltage regulator driver circuitry during a short circuit condition of an alternator field coil includes passively detecting a drop in field coil voltage during an on-portion of a duty cycle of the field coil voltage, wherein the passive detection of the drop in field coil voltage signifies an interrupt event. Responsive to the interrupt event, a logical state of a driver enable control signal is changed so as to deactivate driver circuitry associated with a switching device used to pass field current through the field coil, wherein the driver circuitry, when deactivated, prevents the switching device from passing current regardless of the state of a pulse width modulation (PWM) control signal applied to the driver circuitry.

Abstract: A method of assembling an electrical machine includes programming at least one processor with a stator flux vector estimation scheme. The electrical machine has a stator at least partially extending around a rotor. The electrical machine is electrically coupled to an electric power system. The electric power system transmits at least one phase of electric power to and from the electrical machine with at least partial power conversion. The stator flux vector estimation scheme is programmed to generate at least one stator back-electromagnetic force (back-EMF) signal and to generate at least one stator flux vector signal using the at least one stator back-EMF signal. The at least one stator flux vector signal at least partially represents an estimated rotor position. The method also includes coupling at least one output device in data communication with the at least one processor.

Abstract: Methods and apparatuses are disclosed for producing current with a desired output frequency from one or more fixed or variable speed alternators by varying a saturation level of a portion of the alternator(s) based on a output frequency desired, and preferably then rectifying the output to produce a desired electrical output which may be provided as direct current or alternating current to a suitable load.

Abstract: Power-generation control operation for an in-vehicle electric generator is further stabilized in such a way that, in the case where a signal at an external-control-signal input terminal changes, a function of on/off-controlling a magnetic-field current in a constant cycle is interrupted. In a control apparatus, for an in-vehicle electric generator, that has a function of adjusting a generation voltage to a predetermined voltage, by on/off-controlling a magnetic-field current in a constant cycle, and variably controlling an adjustment voltage, based on an input signal from an external control unit, in the case where a signal at an external-control-signal input terminal is fixed for a long time, the function of on/off-controlling the magnetic-field current in the constant cycle is activated, and in the case where the signal at the external-control-signal input terminal changes, the function of on/off-controlling the magnetic-field current in the constant cycle is interrupted.

Abstract: The power generation control device for a vehicle generator includes an IC circuit including a communication circuit formed therein and having a function of performing a digital communication with an external device through a communication wire, and a resistor mounted to the IC circuit so as to connect the communication circuit to a communication terminal of the power generation control device connected to the communication wire.

Abstract: A method of generating electric power includes providing at least one open-winding generator having at least one winding, wherein the at least one winding has a first terminal and a second terminal. The method also includes electrically coupling the first terminal to a first electric power electronics apparatus via a first electric bus and electrically coupling the second electric terminal to a second electric power electronics apparatus via a second electric bus. The method further includes inducing and regulating a first voltage on the first electric bus and inducing and regulating a second voltage on the second electric bus.

Abstract: A system and method for self-tuning a PID controller utilized with an exciter and generator, which 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 system gain an estimated exciter time constant and an estimated generator time constant with a recursive least square with forgetting factor algorithm, wherein the estimated exciter time constant and the estimated generator time constant are utilized to calculate PID gains by the processor, wherein the processor includes a random input generator that is summed with the output of the PID controller as input to determine the PID gains using the estimated exciter time constant and the estimated generator time constant and the processor compares a digital value of rms generator voltage against a reference voltage as input into the PID controller.

Abstract: In a gas-turbine engine control system having a first control channel inputting the outputs of sensors to calculate and output a first command value indicative of a quantity of fuel to be supplied to the engine and a second control channel inputting the outputs of the sensors to calculate and output a second command value similarly indicative of the quantity of fuel, the second control channel calculates and outputs the second command value using the first command value so long as the instruction to switch the outputs is not generated, while calculates and outputs the second command value, without using the first command value, when the instruction to switch the outputs is generated. With this, immediately after switching to the second command value, the second command value is made substantially equal to and not greatly different from the preceding first command value.

Abstract: An electric power generation control apparatus is connected to an external controller composed of a vehicle interface circuit capable of generating and transferring a power switch-on signal to the electric power generation control apparatus. When receiving the power switch-on signal, the electric power generation control apparatus initiates its operation. The electric power generation control apparatus has a receiving terminal, a control signal receiving circuit, an electric power source circuit, and an electric power generation control circuit. The control signal receiving circuit receives the power switch-on signal through the receiving terminal regardless of the circuit type of the vehicle interface circuit. When the control signal receiving circuit receives the power switch-on signal, the electric power supply circuit initiates to supply the electric power to the electric power generation control circuit.

Abstract: A control section 32 supplies a current obtained by rectifying the output of an exciting winding 5 to a field winding 3 responding to variations in the output voltage of the generator to suppress the variations in the output voltage of the generator. The control section 32 drives a transistor 37 at a duty based on a difference between the output voltage of a main winding 4 and a target voltage and controls the gate voltage of an FET 38 to control a field current to a constant value. A flywheel power generation unit including a control power supply winding 14 is provided as a power source of the control section 32 and a power source for passing an initial current through the field winding 3. A current to be supplied to the field winding 3 from the flywheel power generation unit is merged with an exciting current via a diode 31.

Abstract: A wind power generation system wherein procedure for controlling the blade pitch is changed in accordance with the rate of decrease in the amplitude of the grid voltage, and when over current occurs in the grid-side power converter, the grid-side power converter is brought into the gate-blocked condition whereas the generator-side power converter continues its operation.

Abstract: In a magnet-exciting rotating electric machine, a magnetic field pole part opposing an armature is composed to be divided into a surface magnetic pole part and a magnetic excitation part so as to be capable of being relatively displaced. The magnetic excitation part supplies a magnetic flux to a magnetic salient pole. The magnetic flux from the field magnet is divided into a main magnetic flux pathway that circulates through the armature side and a bypass magnetic flux pathway that does not pass through the armature, and thereby, the magnetic flux of the main magnetic flux pathway is changed. The magnetic resistances of the main magnetic flux pathway and the bypass magnetic flux pathway are composed so that total magnetic flux amount from the field magnet is maintained constant, and then a magnetic force preventing the relative displacement is maintained small.

Abstract: In a power-generator control apparatus installed in a power-generator designed to generate an output voltage at an output terminal thereof, a regulating unit regulates the output voltage so that the regulated output voltage is equivalent to a first target value. When a periodic signal with a predetermined frequency is applied from the outside of the power-generator to the output terminal thereof to be superimposed on the output voltage, a regulated voltage changing unit operatively connected to the regulating unit receives the periodic signal, and compares the frequency of the received periodic signal with a predetermined threshold frequency. The regulated voltage changing unit changes the first target value of the regulated output voltage to a second target value upon the frequency of the received periodic signal being higher than the predetermined threshold frequency.

Abstract: A control and power module for a rotating electric machine comprising a bridge of switches, a plurality of driver circuits for driving a bridge of switches, a control circuit and a plurality of communication connections between driver circuits and a control circuit. When the machine is in a rest mode, at least one connection of the plurality of communication connections is used for transmitting signals between the control circuit and the driver circuits for carrying out a function related to the rest mode of the machine, and when the machine is in the operational mode, all connections of the plurality of communication connections are used for transmitting signals between the control circuit and the driver circuits.

Abstract: A controller employed in conjunction with a synchronous generator monitors the output voltage of the generator. The controller employs the monitored output voltage as feedback that is used to control the excitation provided to an exciter field winding. In addition, the controller applies a control loop to the monitored output voltage that detects and modifies voltage ripple signals within the monitored output voltage to generate a compensated signal that is used to control the excitation to the exciter field winding. In particular, by detecting and modifying voltage ripple signals within the monitored output voltage, the controller is able to counteract armature reaction voltage ripples caused by unbalanced short-circuit faults, thereby preventing the build-up of voltage on the DC link.

Abstract: Methods and systems are disclosed for reducing alternating current ripples in direct current electrical power generation systems with one or more regulated permanent magnet machines. Ripple suppression is achieved, in one aspect, by modulating the control current of a regulated permanent magnet machine.

Abstract: An electric generator with a rotating diode fault detection device built in that operates by comparing a voltage buildup across the exciter DC supply with a preset threshold value and determining if a fault condition is present based on the comparison.

Abstract: The present invention relates to an alternator comprising: an alternator stator (2) comprising a main secondary winding (7) delivering an output voltage; at least one auxiliary winding (3); and an exciter field winding (5) powered by the auxiliary winding(s); a regulator (20) for regulating the output voltage of the alternator; and an alternator rotor (8) comprising an exciter secondary winding (6); a rotary field winding (4) powered by the exciter secondary winding (6); and a control circuit (10) for controlling the power supply to the rotary field winding (4) and configured to maintain the amplitude of the output voltage from the alternator at a predetermined level by controlling the power supply to the rotary field winding (4) in response to a control signal coming from the voltage regulator (20), the auxiliary winding(s) (3) generating a voltage because they are exposed to a varying magnetic field generated by the rotary field winding (4) in rotation.

Abstract: A control apparatus for a vehicular AC generator analyzes, at least, a “HIGH” logic continuation time, a “LOW” logic continuation time and the pulse width duty of an external signal, for the external signal pulse inputted from an external unit. In a case where the “HIGH” logic or “LOW” logic of the external signal pulse has continued for a predetermined time period, the control apparatus controls a generator control voltage as either of adjustment voltages consisting of the two values of an ordinary voltage and a voltage lower than the ordinary voltage. On the other hand, in a case where the “HIGH” logic or “LOW” logic of the external signal pulses are iterated within a predetermined time period, and where the pulse width duty of the external signal falls within a predetermined range, the control apparatus controls the generator control voltage as a multistage or linear adjustment voltage which is the function of the pulse width duty ratio.

Abstract: The present invention uses an electromagnetic device for amplifying an input signal without the use of amplifiers, power supplies, and inverter/converter circuits. The present invention routes an input signal through an electromagnetic device for amplification of the input signal for later use by various loads.

Abstract: The stator of the vehicle-mounted alternator includes a stator core formed with a plurality of slots located along a circumferential direction thereof, and first and second multi-phase windings wound in the slots, the first and second multi-phase windings being spaced from each other by a predetermined electrical angle. An output of the first multi-phase winding is rectified by a first rectifier device, and an output of the second multi-phase winding is rectified by a second rectifier device. The second rectifier device is constituted by a plurality of switching devices. The vehicle-mounted alternator includes a control device to perform on/off control on the switching devices such that a phase angle difference between an output of the first rectifier device and an output of the second rectifier device is varied depending on a rotation speed of the stator.

Abstract: An energy supply system for electrical actuator of a motor vehicle having a engine and battery includes a generator adapted to be driven by the vehicle engine to provide electrical energy to the electric actuator and vehicle battery. A control unit sets an input power provided to the generator by the vehicle engine and is configured to set the output voltage of the generator based on a power request associated with the electric actuator. A method for supplying electrical energy to a vehicle subsystem may be performed using an energy supply system as disclosed.

Abstract: The present invention relates to a control device (1) for an electricity generator set, the generator set comprising: an engine fitted with at least one actuator (2) for controlling fuel admission; an alternator driven by the engine; and a speed regulator (4) for the engine and controlling the actuator(s); the control device being arranged to detect a variation in the load on the alternator as a function of at least one voltage thereof and to control the actuator(s) in such a manner as to compensate for the load variation thus detected; the control device delivering a control signal that acts directly on the actuator(s) taking the place of or being superposed on an output signal of the speed regulator when a variation in load is detected; or the control device delivering a control signal that acts on the actuator(s) via at least a portion of the speed regulator by taking the place of a speed regulator signal.

Abstract: This device is A Specially Improved Automotive Replacement Voltage Regulator for use in the automotive components remanufacturing and original equipment alternator product. Particularly this device has additional transient suppression means for the loads; “high side drive” of the rotor field to eliminate corrosion from the low side short condition; full passivation around the monolithic chip; and a monolithic chip that contains both the power and control devices which permits a simplified heat sink for thermal dissipation.

Abstract: An alternator comprises: an output rectifier converting AC voltage produced in an output armature winding into DC and supplying the DC electric power to a rechargeable battery and a current consumer; an excitation rectifier which is electrically separated from the output rectifier to convert AC voltage produced in an excitation armature winding into DC; and a power generation control unit. The power generation control unit compares the output voltage of the output rectifier or the terminal voltage of the battery with a predetermined reference voltage and controls current supplied to an excitation winding to which the DC voltage outputted from the excitation rectifier is applied, based on the comparison result.

Abstract: An output voltage regulator for an engine-driven generator that can satisfactory suppress fluctuation in output voltage, even when an output waveform of the generator is distorted. An engine revolution period that represents a period of output voltage is detected by use of an ignition signal. Data that represents an output waveform is obtained by squaring and adding up an instantaneous value of the output voltage for one period of engine revolution. Furthermore, a square root of the data is extracted as an effective value. An operation duty of a transistor Q1 provided in an output circuit of an excitation winding L2 that supplies a field current “if” is determined based on a difference between the effective value and a target voltage. The field current “if” changes according to the difference, and the output voltage is thereby regulated according to a load.

Abstract: In a control system for controlling a power generator based on a command value associated with a control parameter, a receiver receives the command signal, a detector detects the command value included in the received command signal, and a determiner determines whether a duration of the detected command value being invariant within a predetermined range exceeds a predetermined allowed duration. In the control system, a controller controls an output of the power-generator based on a predetermined default value within the predetermined range in place of the command value when it is determined that the duration of the detected command value being invariant within the predetermined range exceeds the predetermined allowed duration.

Abstract: A power MOS voltage regulator for recharging batteries of motor vehicles; a voltage generator is selectively connected to a battery, respectively to an earth by a controlled rectifier bridge. The rectifier bridge includes a Schottky diode connected between each phase winding of the generator and the positive terminal of the battery, and a power MOS transistor branched between the phase winding and the earth; a control electrode of the power MOS transistor is driven by a control circuit for controlling the charging state of the battery, to enable the changeover of the power MOS transistor between a conductive state and a non conductive state, and vice versa, when the voltage of the phase winding is zero.

Abstract: A method of operating a power system is provided. The power system has a plurality of generator sets and a bus. The method monitors the bus and generator sets disconnected from the bus. The method supplies to a control device information associated with the operating state of each of the generator sets and the bus. The method determines a relative frequency mismatch and a relative phase mismatch between the frequency and phase of the bus and a generator, and generates a frequency speed bias and a phase speed bias for the generator. The method adds the frequency and phase speed biases to form a total speed bias, tunes the total speed bias to make the frequency and phase speed biases combine in a complementary manner, and connects the generator to the bus when the voltage, frequency, and phase of the generator are within a permissible range of the bus.

Abstract: A method for the control of a static frequency converter, in which an alternating voltage provided by a generator with a first frequency is first rectified in a switched rectifier, and in which the DC-voltage thus present in an intermediate circuit is inverted to an alternating voltage with a grid frequency by means of a switched inverter. The generator is provided with an excitation coil and with means for controlling the power made available to the grid by means of controlling the strength of the excitation field provided by the excitation coil and, if need be, also of the phase relationship between the voltage of the frequency converter and the generator voltage and the grid voltage, respectively. The generator side alternating voltage of the rectifier is controlled to a frequency which is substantially constant in accordance with the first frequency and the inverter is controlled on the basis of the measured value of the DC-voltage in the intermediate circuit.

Abstract: An electromechanical power transfer system that transfers power between a prime mover and a direct current (DC) electrical power system, comprises: a permanent magnet machine (PMM) that has a permanent magnet (PM) rotor coupled to the prime mover, a stator with a multiphase alternating current (AC) winding coupled to an AC bus and a control coil with a winding that has a configuration to generate a magnetic field with flux that varies the reactance of the stator winding with the application of control coil current; a control coil current regulator system to regulate the control coil current; wherein the control coil current regulator system generates a level of the control coil current that regulates current in the stator to a desired level in response to a control coil current feedback loop that comprises a control coil current signal and a DC bus potential feedback loop that comprises a DC potential feedback signal and in a generating mode the main active rectifier system maintains a constant potential on t

Abstract: In a device for detecting errors in a charging line, the device detects an error in the charging line connecting the vehicle generator and an on-board battery. The device includes a bias circuit, a charging line error detecting means, and a warning means. The bias circuit biases a voltage of an external terminal receiving the power generation instruction signal in the vehicle power generation controller with a voltage of an output terminal of the vehicle generator. The charging line error detecting means detects the error in the charging line based on a voltage of an output terminal of the power generation instructing means that is provided within the external controller and generates the power generation instruction signal and a terminal voltage of the on-board battery. When the charging line error detecting means detects the error in the charging line, the warning means performs a warning operation to give notification of the error.

Abstract: A control system for a double-fed induction generator (DFIG) comprising a rotor (1) having rotor windings and a stator (2) having stator windings connectable to a grid for electric power distribution. The control system comprises a converter (17-0, 171), having a clamping unit comprising at least one passive voltage-dependent resistor element (291, 292, 293, 294) for providing a clamping voltage over the rotor windings when the clamping unit is triggered. The invention also relates to a double-fed induction generator (DIFIG) system and to a method for protecting the converter in a power generation system.

Abstract: A control circuit for a generator has a control function that monitors the voltage across a bus capacitor. The circuit delivers excess voltage back to associated stator windings if an unduly high voltage is detected across the bus capacitor.

Abstract: A high efficiency alternator capable of supplying extreme high power output with maximum dissipation of heat. Preferably, the alternator includes dual field coils mounted stationary around a common shaft and dual brushless rotors. The alternator may also include three or more phases, and uniquely wound stator assemblies. The alternator may also include dual, three-phase bridge-type rectifiers and dual voltage regulators. All electrical components are preferably redundant. Air cooling through the interior perimeter of the alternator is preferably provided to cool the housing.

Abstract: The present invention relates to a circuit for producing electricity, the circuit comprising: a first rectifier comprising inputs and an output; a second rectifier comprising inputs and an output, the inputs of the first and second rectifiers being for connection to an alternator so that phases of the alternator are connected in series with the inputs of the first and second rectifiers; at least one switch for short-circuiting the output of the second rectifier or at least a part of the inputs of the second rectifier; and a control unit for controlling the switching of the at least one switch so as to regulate the rectified voltage delivered by the circuit.

Abstract: A highly reliable control device for an AC generator without using a transistor and diode having high withstand voltage is provided.

Abstract: A method and an apparatus are described for monitoring a rotating synchronous electric machine (9), which comprises a rotor having a rotor winding and a stator having a stator winding. The method comprises the steps of determining the stator winding current, determining the stator winding voltage, determining the rotor winding current, and estimating the temperature in at least two positions in the electric machine (9) using a model of the electric machine and the determined current and voltage values. An apparatus according to the invention is provided for carrying out the method.

Abstract: A coordination control device of a power output apparatus includes a coordination control unit. The coordination control unit calculates an intermediate value between the maximum value and minimum value among voltage controls for a first motor generator, and voltage control from an AC voltage control generation unit to generate an AC voltage across neutral points of first and second motor generators, and outputs a value that is each phase voltage control for the first and second motor generators minus the calculated intermediate value to a signal generation unit as the final voltage control for the first and second motor generators.

Abstract: The apparatus, which is for estimating a state of charge of a rechargeable battery charged by a vehicle-mounted power generation apparatus capable of generating a variable output voltage, includes a first function of quantifying charging/discharging history of the rechargeable battery, and a second function of performing estimation of a state of charge of the rechargeable battery on the basis of a parameter which indicates a charging/discharging current of the rechargeable battery when variation of the output voltage of the vehicle-mounted power generation apparatus is below a predetermined value, and the quantified charging/discharging history, while eliminating an effect which polarization of the rechargeable battery due to the charging/discharging history has on the charging/discharging current before the variation of the output voltage becomes below the predetermined value.

Abstract: A controller for a vehicle AC generator that allows the aging test time of a CMOS logic circuit to be reduced is provided. The controller includes a specified signal detecting circuit connected to a third external terminal to detect a specified signal, a voltage selector circuit that generates a voltage selector signal in response to the detection output of the specified signal detecting circuit, and a power supply circuit connected to the first external terminal to output, as internal power supply voltage, first power supply voltage in a first state in which the specified signal is not input to the third external terminal and second power supply voltage higher than the first power supply voltage in a second state in which the specified signal is input to the third external terminal.

Abstract: A generator controller for controlling a permanent magnet generator where each phase of the generator is connectable to a DC link via electrically controllable switches, the controller characterized by a data processor adapted to receive a measurement of generator current output and a demand current, and to form a current error between the demanded value and the measured generator current; derive a target voltage as a function of the current error; and form control signals for the electrically controllable switches as a function of the target voltage.

Abstract: The voltage regulator receives power in A.C. from a permanent magnet voltage generator, having phase windings with a configurable connection, to supply power in D.C. to a battery. The voltage regulator comprises a plurality of semi-bridge rectifiers connected between the terminals of the phase windings of the voltage generator, and a battery power supply terminal; it also comprises a control circuit designed to change over the connection of the phase windings between two different configurations, for example star and delta, in relation to the charging voltage of the battery upon exceeding a threshold value of the phase frequency of the voltage generator.