Abstract: An economic dispatch program optimally allocates load demand specifying real power and reactive power to be generated by a power plant among various power generators in a manner so that each of the power generators are operated within its optimal operating space as defined by a reactive capability curve. Allocating a power demand with consideration of the reactive capability curves of the power generators results in optimal generation of real power and reactive power as specified by the load demand. Alternatively, the economic dispatch program allocates load demand specifying real power and reactive power to be delivered by a power grid among various power plants wherein one or more of the various power plants have capacity limits exhibited by reactive capability curves.

Abstract: An AC generator comprises a rotor and a stator having a three-phase winding. A three-phase inverter is connected to the three-phase winding. Here, the three-phase winding comprises at least two independent three-phase windings. Switching elements for respective phases of the three-phase inverter are connected in parallel by the number of the independent three-phase windings, and in-phase windings are individually connected to their parallel switching elements.

Abstract: A wind turbine control system for twin turbines mounted in common on an accelerator comprising a DC boost converter having pulse width capability, power, speed, current and voltage sensors responsive to an generator driven by one turbine, and a controller.

Abstract: A battery charging control device comprising a control circuit that performs control to keep a voltage across a battery charged by an output of an AC generator around a target value, comprising: a load driving switch inserted between the battery and a load; and a load driving switch control circuit that performs control to turn on the load driving switch when the AC generator generates the output and a voltage across the load is equal to or lower than a set value, and turn off the load driving switch when the voltage across the load exceeds the set value lower than the target value of the voltage across the battery.

Abstract: A control circuit is for an electric power plant including an asynchronous generator of an AC voltage, a motor to rotate a rotor of the asynchronous generator as a function of a first control signal of a developed motor torque, and a bank of capacitors coupled to the asynchronous generator and having a total capacitance varying as function of a second control signal. The control circuit may include a monitor circuit to monitor at least one parameter of the AC voltage, and a control signal generator circuit cooperating with the monitor circuit to generate the first and second control signals by soft-computing techniques both as a function of the frequency and of a representative value of an amplitude of the AC voltage to make the AC voltage have a desired amplitude and frequency.

Abstract: A generator system that includes a three-phase AC machine and an active rectifier bridge employing low on-resistance MOSFET switches for converting the AC current from the machine to a DC current. The system also includes a switch control circuit to switch the MOSFET switches in synchronization with the three-phase current flow. The system determines the phase-to-ground voltages of the machine as inputs to the switch control circuit. The control circuit calculates the phase-to-phase voltages from the phase-to-ground voltages. The control circuit then determines if each of the phase-to-phase voltages is above or below first and second predetermined threshold voltages, where if the phase-to-phase voltage is above the first threshold voltage, the control circuit closes the switch, and if the phase-to-phase voltage is below the second threshold voltage, the control circuit opens the switch.

Abstract: A feedback control method and circuit for inclusion in a control system of an electrical power generating source that comprises a free piston Stirling engine driving a linear alternator. An instantaneous value of a variable, Vinternal, is continuously derived from other sensed and computed parameters and used in a negative feedback control loop of the control system to control engine piston stroke in order to maintain the power produced by the engine equal to the power transferred from the engine to the alternator. Vinternal is the sum of the voltage induced on the alternator winding and the voltage across the equivalent circuit lumped resistance of the alternator winding and a switching mode rectifier connects the alternator winding to an energy storage capacitor or battery.

Abstract: Disclosed herein is an automotive electrical system including a FET based rectifier and method of controlling the FET based rectifier without using either an alternator shaft position sensor or current sensors on each phase of the alternator output to control the switching of the FETs. In accordance with the teachings herein, the voltage and current on the DC bus of the automotive electrical system are sensed and switching of the FETs is controlled by a microcontroller that determines the appropriate switching times based on these sensed parameters.

Abstract: A controller of a generator for a vehicle in the invention includes a battery voltage detecting circuit and an output terminal voltage detecting circuit of an AC generator. A value of a detected voltage of the output terminal voltage of the AC generator is set to be higher than a value of a detected voltage of the battery voltage. A diagnosis alarm signal is outputted when the detected voltage of the battery voltage is lower than the set value while the detected voltage of the output terminal is higher than the set value.

Abstract: The present invention relates to a method for operating a converter system of a wind turbine, wherein the converter system includes converter modules capable of converting electric power produced by a generator to electric power applicable to a utility grid. The converter modules include generator inverters and grid inverters. The method determines the enabling/disabling of the converter modules in response to a parameter related to the variable amount of electric power being produced by the generator. Advantages of the present invention are optimisation of power efficiency of the converter modules and improved reliability of the converter modules. Another advantage is the capability of fast enabling and disabling of the converter modules.

Abstract: A structure of an upwind type wind turbine and the operating method thereof capable of preventing the occurrence of damage of the blades by evading excessive irregular loads from acting on the blades in the slanting direction in the event of power failure when strong wind blows, are provided. In the upwind type wind turbine having a nacelle supported for rotation on a support, the nacelle is rotated to a downwind position by rotating it by 180° from a normal upwind position and kept in stand-by condition at a downwind position when detected wind speed is higher than the predetermined cutout wind speed, which is the reference wind speed for shifting to an idle operation state. When the detected wind speed is higher than the DWSS wind speed determined based on the maximum permissible instantaneous wind speed, the nacelle is rotated from an upwind position to a downwind position and the yaw brake is released.

Abstract: A vehicle generator control device includes a transistor chopper type exciting circuit for supplying an excitation current to a vehicle-mounted electric generator drivable by an engine of the motor vehicle. The exciting circuit comprises a bridge circuit having a first pair of opposing arms formed of respective power transistors and a second pair of opposing arms formed of respective diodes. One of the power transistors is connected to a ground potential of the vehicle-mounted electric generator and the other power transistor is connected to an output terminal of the vehicle-mounted electric generator. When the engine is in a non-operating state, the one transistor is set in an on state and the other power transistor is set in an off state.

Abstract: A method and apparatus are disclosed for controlling a hybrid energy system including at least an energy source having a maximum energy output and an energy storage device. The method includes determining a first amount of energy indicative of an amount of energy associated with the current operating condition of the energy source and determining a second amount of energy indicative of energy associated with the energy storage device. The method also includes estimating a third amount of energy indicative of a difference between the first amount of energy and the maximum energy output. The method further includes controlling the energy source as a function of the second and third amounts of energy.

Abstract: An acquisition circuit for providing a first and a second validation signal based on an alternator output signal has a coupler being adapted for receiving the alternator output signal and for providing a coupling signal having information on the phase of the alternator output signal, the coupler having a capacitive element for coupling the alternator output signal and the coupling signal, the coupler having a resistive element for coupling the coupling signal and a reference signal. The acquisition circuit further has a detector adapted for receiving the coupling signal and for providing the first and second validation signals, wherein the relation between the validation signals is based on the information on the phase of the output signal, wherein the frequency of the alternator output signal is derivable from the validation signals and the validity information is derivable from the relation between the validation signals.

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: 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 power generation apparatus and method includes an AC energization synchronous generator, a switching device for connecting to a network disposed on a stator side of the AC energization synchronous generator, an energizing device for applying a variable frequency AC to a secondary winding of the AC energization synchronous generator, and a first voltage detection unit for detecting a voltage of the switching device on the stator side. A rotational frequency of the AC energization synchronous generator is estimated or calculated based on a frequency of a stator side voltage of the switching device, while the switching device is open.

Abstract: The present invention provides a power converter that can be used to interface a generator that provides variable voltage at variable frequency to a supply network operating at nominally fixed voltage and nominally fixed frequency and including features that allow the power converter to remain connected to the supply network and retain control during supply network fault and transient conditions. The power converter includes a generator bridge electrically connected to the stator of the generator and a network bridge. A dc link is connected between the generator bridge and the network bridge. A filter having network terminals is connected between the network bridge and the supply network. A first controller is provided for controlling the operation of the semiconductor power switching devices of the generator bridge. Similarly, a second controller is provided for controlling the operation of the semiconductor power switching devices of the network bridge.

Abstract: The vehicle-generator output voltage control apparatus includes a voltage control circuit regulating an output voltage of a vehicle generator by controlling a field current flowing into a field winding of the vehicle generator by controlling a conduction state of a switching transistor series-connected to the field winding, a power-generation-state signal output circuit outputting a power-generation-state signal through a transmitting/receiving terminal by changing a voltage at the transmitting/receiving terminal in accordance with conduction state of the switching transistor, and a power generation stop circuit stopping power generating operation of the vehicle generator by causing the voltage control circuit to turn off the switching transistor upon detecting a change of the voltage at the transmitting/receiving terminal caused by a power generation stop signal transmitted from an external control device and received at the transmitting/receiving terminal.

Abstract: A system and method is provided for generating AC power using a synchronous reluctance machine (12) or a salient-pole synchronous machine (102) and a power converter (110). The present invention can be used to achieve power production for a synchronous reluctance machine (12), or can be used to achieve AC power from a traditional salient-pole synchronous machine/starter (102) without dependence upon a rotor current which is subject to failure. In the power generation system, the control system and method can include a power converter (110), controlled by a voltage command and at least one of a measured AC bus (125) current and voltage, and a DC link (120) voltage, for use with a synchronous reluctance machine (102) and a prime mover (116), such that movement of the rotor of the synchronous reluctance machine (102) can be used to produce at least partial AC power generation on the AC bus (125).

Abstract: To shorten a startup interval to reach a synchronizing condition, a phase difference and an amplitude difference between the grid voltage and the stator voltage of one phase of a winding are obtained. The difference in amplitude is decreased prior to or in parallel to synchronizing the stator voltage with the grid voltage. The calculated compensation phase compensation value is used as an initial value for synchronizing at the next synchronizing operation.

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: In a control system, a control unit is connected to a generator and is configured to, when a steep change in a load current flowing through at least one specific electrical load is sensed, control the output of the generator based on the sensed steep change in the load current. This allows variations in a voltage of a power supply system to decrease while converging the voltage of the power supply system to a predetermined target voltage.

Abstract: The power generation controller, which is for regulating an output voltage of a vehicle generator or a battery voltage of a vehicle battery charged by the vehicle generator by controlling an excitation current flowing into an excitation winding of the vehicle generator, includes a switching element connected in series between an output terminal of the vehicle generator and the excitation winding, a voltage control circuit on/off controlling the switching element such that one of the output voltage of the vehicle generator and the battery voltage is kept at a target voltage, and a contact abnormality detector circuit detecting a voltage of the output terminal as the output voltage of the vehicle generator, and detecting abnormality in a contact state between the power generation controller and the output terminal on the basis of the detected output voltage of the vehicle generator.

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: A system and method is provided for generating AC power using a synchronous reluctance machine (12) or a salient-pole synchronous machine (102) and a power converter (110). The present invention can be used to achieve power production for a synchronous reluctance machine (12), or can be used to achieve AC power from a traditional salient-pole synchronous machine/starter (102) without dependence upon a rotor current which is subject to failure. In the power generation system, the control system and method can include a power converter (110), controlled by a voltage command and at least one of a measured AC bus (125) current and voltage, and a DC link (120) voltage, for use with a synchronous reluctance machine (102) and a prime mover (116), such that movement of the rotor of the synchronous reluctance machine (102) can be used to produce at least partial AC power generation on the AC bus (125).

Abstract: A method and a device for providing the supply voltage for the loads of a vehicle on-board electrical system, using a plurality of generators. A regulator unit having at least one output stage transistor is allocated to each of the generators. The output stage transistor is controlled by means of a pulse-width-modulated control signal. The control signal generated in one of the regulator units, or a control signal derived therefrom that describes the pulse-duty factor of the pulse-width-modulated signal, is also supplied to the regulator units of the additional generators, and is also used there to control the output stage transistors. This procedure may bring into agreement the degree of loading of the generators.

Abstract: An electric generation control apparatus for a vehicle alternator receives an electric generation control signal transferred from an ECU placed apart from the control apparatus through a data transfer line. The control apparatus has a voltage comparator, a communication state judgment circuit, a serial data communication receiver, a PWM communication receiver, and an electric generation control circuit. The voltage comparator acts as a receiver of receiving the electric generation control signal transferred through the data transfer line. The communication state judgment circuit judges whether the received signal is a PWM signal or a serial data signal. The serial data communication receiver and the PWM communication receiver demodulate an electric generation control parameter from the received control signal based on the judgment result. The electric generation control circuit controls the operation of the vehicle alternator based on the electric generation control parameter demodulated.

Abstract: A control apparatus controls the generation of a vehicle electric generator having an armature winding, excitation winding and rectifier connected to the armature winding. The apparatus includes a flywheel diode connected to the excitation winding in parallel, a switch element connected to the excitation winding, a control signal setting circuit, and a signal output section. The setting circuit controls a duty ratio of the switch element in correspondence to a first generation status of the generator to control electric current flowing through the excitation winding while varying a switching frequency of the generator depending on a second generation status of the generator. The signal output section is connected to a junction point between the excitation winding and the switch element and outputs a signal, involving a duty ratio associated with the first generation status and a switching frequency associated with the second generation status, to an external device.

Abstract: An economic dispatch program optimally allocates load demand specifying real power and reactive power to be generated by a power plant among various power generators in a manner so that each of the power generators are operated within its optimal operating space as defined by a reactive capability curve. Allocating a power demand with consideration of the reactive capability curves of the power generators results in optimal generation of real power and reactive power as specified by the load demand. Alternatively, the economic dispatch program allocates load demand specifying real power and reactive power to be delivered by a power grid among various power plants wherein one or more of the various power plants have capacity limits exhibited by reactive capability curves.

Abstract: An electric generation control apparatus for a vehicle alternator receives an electric generation control signal transferred from an ECU placed apart from the control apparatus through a data transfer line. The control apparatus has a voltage comparator, a communication state judgment circuit, a serial data communication receiver, a PWM communication receiver, and an electric generation control circuit. The voltage comparator acts as a receiver of receiving the electric generation control signal transferred through the data transfer line. The communication state judgment circuit judges whether the received signal is a PWM signal or a serial data signal. The serial data communication receiver and the PWM communication receiver demodulate an electric generation control parameter from the received control signal based on the judgment result. The electric generation control circuit controls the operation of the vehicle alternator based on the electric generation control parameter demodulated.

Abstract: Switching devices control the rectification and flow of alternating current power from a source such as an alternator to a load such as a battery in response to both the voltage of the battery and a minimum selected time period that is selected to eliminate or reduce an imbalance between various phases or polarities in possible current carrying paths. The selected time period may be constant or a predetermined function of variables such as the speed of the alternator.

Abstract: Disclosed herein is an automotive electrical system including a FET based rectifier and method of controlling the FET based rectifier without using either an alternator shaft position sensor or current sensors on each phase of the alternator output to control the switching of the FETs. In accordance with the teachings herein, the voltage and current on the DC bus of the automotive electrical system are sensed and switching of the FETs is controlled by a microcontroller that determines the appropriate switching times based on these sensed parameters.

Abstract: A rotary electric apparatus, such as on-vehicle three-phase AC generator (i.e., alternator) comprises a main rotary unit, a semiconductor power converter, and an air cooling mechanism. The main rotary unit is provided with a rotor and an armature disposed as a stator around the armature. The armature has armature windings wound therearound. The semiconductor power converter is disposed together with the main rotary unit. The air cooling mechanism cools down the semiconductor power converter. This mechanism comprises a fan motor driven in response to an AC (alternating current) excitation by current coming from the armature windings.

Abstract: A power generation control device enables to conduct appropriate charge control and load limitations even if a technique (charge control technique) for restricting power generation by a generator in an accelerating state of a movable body is adopted in a movable body such as a vehicle in which a technique (load limiting technique) for imposing limitations on a power supply when a quantity of suppliable electricity decreased has been adopted. The power generation control device for controlling a generator for a movable body which stores electric power in a battery comprises a unit for restricting power generation by the generator based on a battery suppliable current which can be taken out of the battery, a quantity of electricity generated by the generator, an essential supply current consumed by an electric load to which electric power must be supplied and a load working current consumed by an electric load which does not necessarily require a power supply.

Abstract: A combined heat and AC power generating system is disclosed having black start capability for the full time, simultaneous production of both electricity and heat. Heat generated within the system is captured and used for heating applications such as heating building air and tap water. The power generating system comprises an engine, generator, rectifier, variable frequency drive inverter, and inverter control electronics. The system provides improved efficiency and prolonged engine life by always operating the engine with its throttle fully open to obtain maximum efficiency and the engine is normally operated near its stall point. In this operating state the inverter control electronics adjust the power output from the inverter to control the speed of the engine. This is done by increasing the power output from the inverter when the power drawn by the load decreases. This causes the engine to operate closer to its stall point and it slows down.

Abstract: A generator control apparatus, for controlling electrical generation operation of a vehicle alternator, has a LAN circuit and a dedicated communication circuit, respectively communicating with an external control apparatus (e.g., engine ECU) via a LAN and via a dedicated signal line. When a selection signal is transmitted from the external control apparatus, designating a specific signal to be transmitted to or from the generator control apparatus, communication of that signal is performed via the dedicated signal line, enabling TDM communication of plural signals via the LAN concurrent with direct communication of a specific signal via the dedicated signal line.

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 present invention relates to a power generation controller of a vehicle power generator, which includes: voltage detection means for sampling a voltage of a battery based on a reference clock signal; duty range setting means for setting a range for an ON/OFF ratio of a field switching element from the rotation speed of the power generator; control duty computation means for computing the ON/OFF ratio of the field switching element based on thus set duty range from a deviation between a power generation target voltage and voltage information as a result of sampling; and field PWM drive means for controlling the ON/OFF switching operation of the field switching element with an interval based on the reference clock signal from the computed ON/OFF ratio.

Abstract: An AC generator comprises a rotor and a stator having a three-phase winding. A three-phase inverter is connected to the three-phase winding. Here, the three-phase winding comprises at least two independent three-phase windings. Switching elements for respective phases of the three-phase inverter are connected in parallel by the number of the independent three-phase windings, and in-phase windings are individually connected to their parallel switching elements.

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: The invention provides an electrical generating system comprising an AC electrical generator (G) having an output, and a capacitor arrangement (Ca) provided at the output of the generator and arranged so as to offset a drop of voltage from no-load to full-load occurring at the output of the generator. As described, the generator (G) is a permanent-magnet generator having a plurality of terminals and associated output lines, and the capacitor arrangement comprises a respective capacitor (Ca) connected in series in each of the output lines, with the value of the capacitance of each capacitor being selected such that a drop of voltage from no-load to full-load occurring at the associated generator terminal is substantially offset at an output terminal of each said capacitor.

Abstract: An inverter device is mounted on the rotating electric machine body The inverter device includes a module unit having a converter circuit and a control unit that controls the operation of the converter circuit. The converter circuit is configured by connecting a plurality of the following series circuits in parallel, each of the series circuits includes a P-channel MOS semiconductor device disposed at a higher potential side and an N-channel MOS semiconductor device disposed at a lower potential side which are electrically connected in series. An electric power that is supplied from a battery or an electric power that is supplied to the battery is controlled.

Abstract: To shorten a startup interval to reach a synchronizing condition, a phase difference and an amplitude difference between the grid voltage and the stator voltage of one phase of a winding are obtained. The difference in amplitude is decreased prior to or in parallel to synchronizing the stator voltage with the grid voltage. The calculated compensation phase compensation value is used as an initial value for synchronizing at the next synchronizing operation.

Abstract: The invention is a control system that, among other things, controls a permanent magnet alternator and provides relatively accurate voltage regulation. The control system may include one or more of the following: (1) a rectification system to rectify and regulate the output voltage of an alternator, (2) a rectifier/limiter used as an electrical power source to a boost type regulator, (3) a multimode rectifier/limiter, (4) a DC to AC inverter bridge, and (5) power switches employed in the system to minimize the switching energy that would otherwise be dissipated in the power switches as heat.

Abstract: There is provided an adjustable integral component in a feedback loop of a closed loop control system. The closed loop control system controls an output signal of an electric generator. The adjustable integral component provides an integral signal. The integral signal is proportional to the output signal in a first operational mode. The integral signal is proportional to a time integral of an output signal in a second operational mode. According to another aspect of the invention there is provided a non-linear component in a feedback loop of a closed loop control system. The closed loop control system controls an output signal of an electric generator. The electric generator having non-linear characteristics. The feedback loop has an error signal, of which the output signal is responsive to. The non-linear component receives a load signal and provides a non-linear signal related to the non-linear characteristics of the electric generator. The error signal is responsive to the non-linear signal.

Abstract: Apparatus and methods are provided for controlling a voltage output of an alternator having a regulated voltage control (RVC). The apparatus includes a processor configured to transmit one of at least two control signals and a switch coupled to the processor and configured to select one of the control signals. One of the control signals is an RVC enable signal, and another control signal is a voltage boost signal. The method includes determining whether RVC requires override, selecting an output voltage mode of the alternator, activating a boosted voltage mode of the alternator by disabling RVC when RVC requires override, and activating an RVC mode by enabling RVC when the RVC does not require override or upon an occurrence of a lapse of a pre-determined amount of time.

Abstract: A control apparatus for an on-vehicle generator is provided. The generator, driven to rotate by an on-vehicle engine, is provided with stator windings, rectifiers, a field winding, and a voltage control apparatus (i.e., the control apparatus for the on-vehicle generator). The voltage control apparatus comprises a switching element (including power transistors, for example) selectably and electrically connects or disconnects a current path between the field winding and a power supply to provide the field winding with current; a storage element (for example, a battery); and a regeneration element (for example, free wheel diodes) provides the storage element with current flowing through the field winding when the switching element is turned off.

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 neutral point diode having three connecting terminals electrically commonly connected to each other is used in a type for connecting each generating coil of a three-phase alternating current electric generator for a vehicle in a Y-shape connection. The coil terminal of a neutral point side of each generating coil is connected to each of the three connecting terminals of this neutral point diode. A diode having two connecting terminals electrically commonly connected to each other is used in a type for connecting each generating coil in a ?-shape connection. The coil terminals of two adjacent generating coils are connected to the respective two connecting terminals of this diode. In both the types, one coil terminal is connected to one connecting terminal and a connecting work is simplified.