Abstract: Described herein are electric vehicles comprising power distribution systems and methods of operating thereof. Specifically, a power distribution system is mechanically coupled to an electric motor, a road wheel, and an auxiliary unit. This system is configured to switch among multiple operating modes and selectively transfer mechanical power among the electric motor, wheel, and auxiliary unit. For example, the power distribution system is configured to transfer mechanical power between the electric motor and the road wheel, but not the auxiliary unit, when switched to a wheel operating mode. The power distribution system is configured to transfer mechanical power between the electric motor and the auxiliary unit, but not the road wheel, when switched to an auxiliary operating mode. The power distribution system is configured to transfer mechanical power between the electric motor, the auxiliary unit, and the road wheel when the system is switched to a combined operating mode.

Abstract: A power conversion device of an embodiment includes a rectifier that full-wave rectifies alternating current of a plurality of phases supplied from a power supply side, a capacitor that smoothes an output voltage of the rectifier, a voltage detection unit that detects the smoothed voltage, and an open phase detection unit that detects that an open phase has occurred in the alternating current of the plurality of phases based on a component having a frequency that is twice as high as a fundamental frequency of the alternating current of the plurality of phases included in frequency components of the smoothed voltage.

Abstract: When an estimation state of a road noise value based on an angular acceleration of a wheel is a proper estimation state, it is determined whether a background noise of the vehicle is in the high background or the low background noise state according to magnitudes of the road noise value and a predetermined threshold value. When the estimation state is not the proper estimation state, it is determined that the background noise of the vehicle is in the low background noise state regardless of road noise value. When the background noise is in the high background noise state, an output of the in-vehicle actuator is set so noise accompanying an operation of the in-vehicle actuator becomes relatively large. When the background noise is in the low background noise state, an output of the in-vehicle actuator is set so that noise accompanying an operation of the in-vehicle actuator becomes relatively small.

Abstract: An adaptive filter system and a method for controlling the adaptive filter system are described herein. The system can includes one or more filters to attenuate incoming light. The one or more filters can be moved by one or more actuators. The method can capture image data from an imaging device through the one or more filters. Information can be determined from the captured image data. The one or more filters can be moved to a position for capturing image data based on the information.

Abstract: A fan motor controller comprises a pulse width modulation signal, a switch circuit, a control unit, and a frequency judging unit. The switch circuit is coupled to a fan motor for supplying a driving current to the fan motor. The control unit generates a control signal to the switch circuit, so as to control the switch circuit. The frequency judging unit receives the pulse width modulation signal for generating a judging signal to the control unit. The pulse width modulation signal is configured to adjust a speed of a fan. The pulse width modulation signal has a frequency. Based on the frequency and a judgment rule, the fan motor controller is configured to attain the function of switching between the forward direction and the reverse direction of the fan.

Abstract: A wristwatch includes a first motor that drives a first hour hand, a first control circuit electrically coupled to the first motor and outputting a first motor drive signal, and a second control circuit electrically coupled to the first motor and outputting a second motor drive signal. When the first control circuit outputs the first motor drive signal, the second control circuit is in a high impedance state to the input of the first motor drive signal, and when the second control circuit outputs the second motor drive signal, the first control circuit is in the high impedance state to the input of the second motor drive signal.

Abstract: An electric device control method controls an electric device that includes an internal combustion engine, a first electric motor that receives a driving force of the internal combustion engine to carry out power generation, and a second electric motor connected to a drive shaft. The method sets a rotational speed of the internal combustion engine to increase as a vehicle speed of the vehicle increases while the power generation is carried out by the first electric motor. Where the driving force required by the second electric motor becomes zero or negative while the first electric motor is carrying out power generation by the driving force of the internal combustion engine, the internal combustion engine is stopped where the vehicle speed is greater than or equal to a first threshold value, and the power generation is continued where the vehicle speed is less than the first threshold value.

Abstract: A management apparatus manages electric power transfer between a power system and a secondary battery mounted in a vehicle and storing electric power for traveling. The management apparatus includes a storage configured to store an upper limit number of rotations of a rotating machine included in the vehicle, and a controller configured to acquire an integrated number of rotations of the rotating machine that is measured from a start time of a warranty period of the vehicle and to limit electric power transfer between the power system and the secondary battery when the integrated number of rotations is equal to or greater than the upper limit number of rotations.

Abstract: A control system has a microcontroller (242) that receives a mode request (MR), a command-generating device (244) to supply commands and to transfer the mode request (MS) to an output pin of the microcontroller (242), and a device for detecting accidental starting (258), as well as a pilot (260) that supplies an output command signal to the switch (222; 224). The pilot (260) is connected to the output pin to receive the transmitted mode request (MS). The output pin is connected to an input pin of the microcontroller (242) to receive the transmitted mode request (MS), and the accidental starting detection device (258) detects when the transmitted mode request (MS) received on the input pin indicates a motor mode even though the mode request (MR) received by the microcontroller (242) indicates an alternator mode and, when this is the case, sends an inhibition command (INHIB_P; INHIB_T) to the pilot (260).

Abstract: The present invention relates to an on-load tap changer control method for a power transformer in a power system. The power transformer has a primary side for a connection to a first grid in which electric power is generated, and a secondary side for connection to a second grid in which electrical power is consumed, the power transformer being equipped with an on-load tap changer. The method includes measuring the voltage and current at least on the primary side (u1, i1) or on the secondary side (u2 i2) of the power transformer, processing said measured voltages (u1; u2) and currents (i1; i2) in order to derive prospective reactive power at the output of the power transformer after prospective tap-change, comparing prospective reactive power to a predefined set-point, and—initiating tap-change of on-load tap changer if prospective reactive power is closer to said predefined set-point than actual reactive power.

Abstract: The present invention comprises a reconfigurable variable voltage battery. One or more variable voltage battery (VVB) modules are connected in series to form a stacked variable voltage battery (SVVB or Stacked VVB). A variable voltage battery module may comprise at least one battery cell and processor controlled switches adapted to vary the output of the variable voltage battery module. By separately configuring the switches of each VVB module, the output of the stacked VVB module can produce any voltage up to the full sum of the voltages of all the cells in the individual VVB modules. In addition, charge balancing can easily be achieved with a stacked VVB configuration, as some VVB modules can be bypassed (e.g., by setting select switches to simulate a short condition) either to prioritize the discharging of stronger VVB modules, or to prioritize the charging of weaker VVB modules.

Abstract: An electric motor control device performing feedback control of a state amount of an electric motor or a load and being capable of changing a control bandwidth of a feedback control system includes: a notch filter arranged in the feedback control system and having a filter coefficient which is changeable; a notch control section which changes a notch frequency as a center frequency of the notch filter to remove an oscillation component attributable to mechanical resonance related to the electric motor; and a control coefficient setting section which changes at least one of the control bandwidth or the filter coefficient of the notch filter in accordance with the control bandwidth and the notch frequency to stabilize the feedback control system.

Abstract: The present disclosure provides a system and method that provides active damping at the input of a motor drive system without the need for the hardware used in conventional and RC damping circuits. According to the disclosure a virtual damping network is realised at the input of the motor drive system based on modification of field-oriented control, FOC. More specifically, a control algorithm creates a virtual damping impedance at the motor drive input by applying a damping algorithm to both q and d components of the motor current.

Abstract: A motor drive device capable of switching the connection configuration of the stator windings of a motor includes three relays each including a first contact, a second contact, and a contact plate, where the contact plate has one terminal coupled to a stator winding of one phase among the stator windings and the contact plate has another terminal to be connected to the first contact or to the second contact; and a control unit to control the three relays to cause all the three relays to have a same connection state in a case in which not all the three relays have a same connection state with respect to connections between the another terminal of the contact plate and the first contact and the second contact.

Abstract: A highly reliable electromechanical integral motor is provided. In the electromechanical integral motor including an axial gap type motor and a power conversion control device, the power conversion control device is mounted on an end bracket portion of the motor. Additionally, a space is provided between the end bracket portion of the motor and the power conversion control device. Further, the end bracket portion of the motor and the power conversion control device are fixed by a plurality of fixing members, and at least one set of the plurality of fixing members is disposed to be spaced apart from each other.

Abstract: A method for determining a droop response profile of a rotating electrical machine supplying electricity to an electrical grid having a network frequency varying on either side of a nominal frequency, in which a measured value of the rotation speed of the rotating machine is retrieved, and the droop response parameters dependent on the measured speed value are defined. The droop response profile is a graph centered on the coordinates of an origin point between 99% and 101% of the measured speed and defined by at least two points of coordinates in the case of underspeed and/or by at least two points of coordinates in the case of overspeed, each of the points having for its abscissa a speed value as a percentage of the measured speed, and for the ordinates, a filtered speed value as a percentage of the measured speed modulated by at least one of the droop response parameters.

Abstract: While a power storage installation operates as a virtual generator to maintain an power storage amount, a power generating installation calculates a first generated power change rate command value from a deviation between a frequency of a power distribution system and a frequency command value, calculates a second generated power change rate command value from received power measured by a received power measurer, calculates a second active power command value by integrating a generated power change rate command value to which the first generated power change rate command value and the second generated power change rate command value are added, and controls an output of the power generating installation based on the second active power command value.

Abstract: A power-on/off command is output to a breaker for switching when a frequency difference between a plurality of electric power supply sources is within a predetermined range and a phase difference between the plurality of electric power supply sources is within a predetermined range, in switching of electric power supply between the plurality of electric power supply sources. A generator drive rotation speed of a transmission device is feedback controlled so that the frequency difference is maintained at a value within the predetermined range and the phase difference is maintained at a value within the predetermined range when the detected frequency difference is within the predetermined range and the detected phase difference is within the predetermined range. A generator rotation speed command is calculated by adding to the rotation speed command of the transmission device an output value obtained by subjecting the detected phase difference to a proportional-integral-control.

Abstract: A motor control device is configured to feedback-control state quantity of a motor or a mechanical load, and the device includes a first notch filter disposed inside a feedback control system and configured to change a frequency component to be removed, a first notch controller configured to change a first notch frequency as a center frequency of the first notch filter, a change rate calculator configured to successively calculate a notch frequency change rate indicating a change amount per unit time of the first notch frequency, and a change rate monitor configured to output a signal indicating that the notch frequency change rate has a value outside a first predetermined range when the notch frequency change rate has the value outside the first predetermined range.

Abstract: A system includes at least one compressor, at least two turbines, and at least two combustors, each fluidically coupled to a respective turbine of the at least two turbines and configured to receive compressed fluid from the at least one compressor. The system further includes at least two motor-generators, each operably coupled to a respective turbine of the at least two turbines and configured to convert electrical energy to mechanical energy to drive a respective propulsor to which the respective motor-generator is operably coupled and to convert mechanical energy from the respective turbine to electrical energy. The system further includes at least two propulsors, each operably coupled to a respective turbine of the at least two turbines and configured to be driven by the respective turbine, a respective motor-generator to which the respective propulsor is operably coupled via the respective turbine, or both the respective turbine and the respective motor-generator.

Abstract: A drive force control system appropriately controls motors each connected to a corresponding one of drive wheels, so that a vehicle can be propelled with high efficiency. First motor and second motors are controlled in such a manner that a sum of torques transmitted to a right front wheel and a left rear wheel equals to a total value of required torques of the right front wheel and the left rear wheel. A target torque of the first motor and a target torque of the second motor achieving a smallest amount of power output from an electrical power source, for the output torques from the first motor and the second motor are calculated. A torque is generated by the first motor based on the target torque of the first motor calculated, and a torque is generated by the second motor based on the target torque of the second motor calculated.

Abstract: A method is provided for connecting a main converter, e.g. for use in a power plant for regenerative energy having a generator, to a power grid. The method includes providing energy from the pre-charge unit to at least one of at least two converter paths. The at least one converter path is pre-charged using the energy provided from the pre-charge unit. At least one further converter path of the at least two converter paths is pre-charged using the energy provided from the pre-charge unit via the at least one converter path through the grid side converter of the at least one converter path and the grid side converter of the at least one further converter path. The main converter is connected to the power grid by closing the grid breaker.

Abstract: A method of controlling torque of a permanent magnet synchronous motor (PMSM) by using a speed-torque lookup table may include: receiving a current direct-current (DC) link voltage of an inverter configured to drive the PMSM and a speed of a rotor of the PMSM; calculating a change ratio of a DC link voltage based on the current DC link voltage and a DC link voltage at a time when the speed-torque lookup table is generated; calculating a normalized speed of the rotor according to a change in the DC link voltage by using the speed of the rotor and the change ratio of the DC link voltage; and/or transferring the normalized speed of the rotor as an input to the speed-torque lookup table.

Abstract: Systems for generating energy are disclosed. An example system for generating energy includes an internal combustion engine that is to load a shaft with a torque. The internal combustion engine is to generate waste heat. A Rankine cycle plant is to be fed waste heat from the internal combustion engine to operate therewith a turbine coupled to a first electric generator. The first electric generator is connected to an electric motor which is coupled rotationally to the shaft to introduce an additional torque. The internal combustion engine is to drive a second electric generator. The second electric generator is to feed electric current into a high-power network configured to provide electrical power in a megawatt range.

Abstract: An electrical circuit, in particular a circuit used for generating electric power, wherein this circuit comprises a generator with n phases, a converter and a transformer to which a p-phase load can be connected. The converter comprises m partial converters, each of the partial converters is composed of p units and each of these units is provided with n/m switching circuits. The switching circuits of the individual units are connected symmetrical to the generator.

Abstract: The method according to the invention involves limiting the charging of a vehicle alternator by only authorizing progressive augmentation of a current duty cycle (DC) of an excitation signal (7) of the alternator from an initial duty cycle to an expected duty cycle (EpsU) calculated by a control loop (1, 5, 6) of the alternator. According to the invention, a complementary limitation of the charging of the alternator involves limiting the increase of the current duty cycle (DC) according to at least one parameter of the heat engine involving an angular acceleration (mot) and/or a rotation speed (Nmot) of the heat motor. In particular, this complementary limitation can additionally involve limiting the increase of the current duty cycle (DC) according to a negative value of the angular acceleration (mot).

Abstract: A rotary electric starter machine including an electric motor, a housing surrounding the motor, and a pinion connected to the motor, at least one of the motor and the housing comprising a magnetically active portion of the machine, wherein the magnetically active motor portion is made of an enhanced performance steel material having a flux density at a given magnetizing force level that is at least about 20% less than the flux density at the given magnetic force level of a conventional low carbon steel material chosen from the group consisting of AISI 1008 and AISI 1010 steel.

Abstract: Approximating loci of eigenvalues or characteristic gains of a return ratio matrix of a model of a multi-phase power converter circuit by the loci of the d-d and q-q elements of said synchronous frame of reference applied to said model, allows determination and assessment of stability of the circuit or forbidden operational parameters of the combination of an AC power source and a power converter at an interface thereof by application of a standard Nyquist stability criterion.

Abstract: A method for generating hydraulic power in an aircraft, the aircraft having a drive system comprising at least one transmission shaft connected to a power control unit, the power control unit having an electric motor and a hydraulic displacement machine connected to a differential gear unit for driving a common output shaft. The method includes switching the hydraulic displacement machine into a pump mode, arresting the output shaft, rotating the electric motor such that the hydraulic displacement machine is driven due to the arrested output shaft and supplying the fluid flow into a hydraulic system. A drive system of an aircraft may thereby be used for either moving control surfaces or for generating hydraulic power in an aircraft. This hydraulic power may be used to cover hydraulic load peaks during aircraft operation or to power hydraulic devices without the need of additional hydraulic power generation components.

Abstract: A vehicle includes an engine, a first MG (motor generator), a second MG, a motive power split device, and an ECU. ECU temporarily determines whether or not an imbalance abnormality has occurred based on an air-fuel ratio, and when it is temporarily determined that the imbalance abnormality is present, controls the engine such that the engine is in an idle state and formally determines whether or not the imbalance abnormality has occurred based on fluctuations in engine rotation speed. During a stop at idle, ECU determines whether or not the formal determination process of the imbalance determination is ongoing and carries out pressing control to cause the first MG to generate pressing torque Tp when the formal determination process is not ongoing and does not carry out the pressing control so as not to cause the first MG to generate pressing torque Tp when the formal determination process is ongoing.

Abstract: A generator drive system for the generator (3) of an internal combustion engine (1), including a flexible drive having a traction mechanism (5) which is guided across a generator pulley (6) driving the generator (3). The generator (3) is configured and electrically wired such that the generator (3) can be temporarily driven as a motor, and the generator (3) is coupled to the generator pulley (6) or the crankshaft pulley (7) is coupled to the crankshaft (8) via an overrunning clutch (4) which allows the generator (3), when operated as a motor, running faster than the generator pulley (6) or, taking into consideration a gear ratio, the crankshaft (8).

Abstract: Apparatus for controlling and diagnosing a prime mover of a vehicle traction system includes an alternator having a rotor and coupled to a crankshaft of the prime mover, a source of electrical energy, a position sensor supplying a position signal representative of an angular position of the rotor, and a control computer. The computer supplies energy to the alternator to crank the prime mover at a controlled rate. In a diagnosis mode, the computer generates a condition signal indicative of a malfunction of the prime mover, from a compression signal derived from an acceleration signal which is derived from the position signal. In a barring-over mode, the computer also supplies energy to the alternator and monitors the position signal to place the crankshaft in a desired angular position in an operation separate from diagnosis mode.

Abstract: The regulator/brush-holder assembly (1) comprises a support (2) and an electrical circuit (5, 6) comprising a regulating element (5) connected by microwires to a trace circuit (6). The electrical circuit further includes a filtering circuit (10) separate from the regulating element and connected by microwires to the trace circuit. According to one particular embodiment, the filtering circuit comprises an insulating substrate (11) and surface-mounted components (C1, C2, S1, S2, V). A ground plane (19) and/or one or more ground pads may be provided for connection to a ground trace of the trace circuit. The filtration frequencies of the filter circuit extend from 100 kHz to 1 GHz.

Abstract: Objects are to set up control of a plurality of motor generators in a case where a battery is charged or discharged, to secure both a target driving force and target charging/discharging, and to have the breath of control of using electric power of the battery under a more specific condition.

Abstract: Systems and methods for monitoring excitation of a generator based on a faulty status of a generator breaker are provided. According to one embodiment, a system may include a controller and a processor communicatively coupled to the controller. The processor may be configured to receive, from a contact associated with a generator breaker, a reported status of the generator breaker, receive operational data associated with one or more parameters of a generator associated with the generator breaker, and correlate the reported status of the generator breaker and the operational data. Based on the correlation, the processor may establish an actual status of the generator breaker, and, based on the actual status, selectively modify a mode of excitation of the generator.

Abstract: A multi-port reconfigurable battery has at least one bank of statically joined series connected battery cells, each including a positive and negative pole connected through switches to respective output connections on at least one port. Processor controlled switches reconfigure the cells to provide power for electrical loads on one or more ports and simultaneously provide charging on one or more other ports. An alternative configuration divides groups of series connected cells into separate battery banks that permit other configurations. Ports are configurable to share one electrically common connection with other ports providing a simplified configuration (multi-tap reconfigurable battery). Applications include selectable motor speed control and battery regeneration schemes matched to motor output, and single or multiphase AC power output at selectable frequencies for use as an Uninterruptible Power Supply. The battery is also described as a power source for a forced-air induction system (e.g.

Abstract: An overcurrent fault protection method includes detecting an overcurrent fault in a variable frequency electric power generation system having a first main generator connected to a first alternating current bus through a first generator line contactor, a second main generator connected to a second alternating current bus through a second generator line contactor and an auxiliary power generator connected to a plurality of bus tie contactors, through a third generator line contactor, and connected to at least one of the first and second alternating current buses through the plurality of bus tie contactors, in response to detecting the overcurrent fault, locking out one or more of the plurality of bus tie contactors and in response to a continued detection of the overcurrent fault, opening at least one of the first second and third generator line contactors.

Abstract: A traction motor system calculates motor flux by generating a real time effective resistance of a resistance grid calculated from motor torque and measured voltage on a DC link. Calculating effective resistance avoids solely relying on DC link voltage, which can be influenced by conditions such as wheel slip and drop out of one or more resistance grids. The effective resistance calculation is based on nominal motor values using known power levels and conditions. From these nominal values and the effective resistance, various scaling factors based on actual motor power can be generated and used to adjust a nominal flux reference to more accurately reflect actual motor flux. The scaling factors include power and torque scaling factors and a resistance scaling factor that is active during conditions such as wheel slip.

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

Abstract: A method and system for starting and operating an electrically driven load, e.g. a compressor or pump, by power supply from a mechanical driver, e.g. a turbine or combustion engine, whereby the load is mechanically connected to a first electrical machine, and the mechanical driver is mechanically connected to a second electrical machine. The first electrical machine is electrically interconnected to the second electrical machine at a standstill or when the first and or second machine have low speed. In an acceleration phase, the first electrical machine is accelerated by accelerating the second electrical machine with the mechanical driver. When the first electrical machine has reached a predefined rotational speed, the first machine is synchronized with a local electrical power network and connected it to that network.

Abstract: A vehicle power system including an unregulated alternator; a saturable reactor receiving an output AC voltage from the alternator and generating a reduced AC voltage in response to a bias signal; and an active rectifier rectifying the reduced AC voltage to a DC voltage.

Abstract: A reconfigurable battery has at least one bank of statically joined series connected battery cells, each cell including a positive and a negative pole. The poles connect through switches to respective output connections. Activating a set of processor controlled switches reconfigures at least some of the battery cells into a configuration to provide a voltage across the output connections. The output battery voltage may vary intermediately between zero volts and the maximum voltage produced by the series connected battery cells. An alternative configuration of switches divides groups of series connected battery cells into separate battery banks that permit other battery cell configurations. Duty cycle modulation of the switches allows intermediate control of output voltage with reduced switching transients. Reconfigurable battery cells used in combination with an electric motor permit selectable speed control and battery regeneration schemes matched to motor output.

Abstract: A generator protection device is provided. The generator protection device includes a safety factor estimation module configured to estimate a safety factor as a function of a terminal voltage (VS) of a source-end generator, and a swing center voltage (SCV) between the source-end generator and a receiving-end generator. The system further includes a comparison module configured to compare the estimated safety factor with a defined safety threshold limit, and a decision module configured to trigger an alarm or a generator circuit breaker trip action or both, based on the comparison between the estimated safety factor and the defined safety threshold limit.

Abstract: A system for driving a three phase motor using a variable speed drive in communication with an alternator driven by a prime mover. A rectifier can be connected with the alternator. The system can also include a logic and alternator field drive configured to sense voltage leaving the rectifier and controlling the alternator to maintain a predetermined output from the rectifier.

Abstract: A system and method for efficiently regulating the fuel consumption of a variable speed combustion engine used to control loads such as a hoist motor in a mobile gantry crane based on load motor speed commands issued by a crane operator. The system and method can rely on a programmable logic controller to issue engine fuel commands to regulate engine speed based on interpolations derived from data representing the relationship between load motor voltage and engine speed and data representing the relationship between engine speed and engine power capacity. The method may also be used in modified form by combustion engines which need digital fixed speed commands.

Abstract: A shunt regulated permanent magnet alternator voltage source includes a permanent magnet alternator, a shunt regulator, and a pulse width modulation controller. Also included is a load controller capable of detecting a PMA margin.

Abstract: A method for controlling an electric power flow between a high-voltage battery and an electrically-powered torque machine of a powertrain system includes, upon violating a constraint associated with the electric power flow during operation of the powertrain system, executing a battery power control scheme for controlling the electric power flow including commanding an initial state for a parameter of the electric power flow, the initial state for the parameter of the electric power flow including a maximum estimated state for the parameter of the electric power flow occurring during one of a plurality of selected ones of previous timesteps.

Abstract: Heavy equipment is designed for operation in a substantially-repetitive work cycle that includes lifting, rotating, and lowering steps. The heavy equipment includes a generator, an electrical bus, an energy storage component, and working components. The generator provides a substantially constant electrical output to the electrical bus, which is communicated to the working components. As such, the working components of the heavy equipment are driven directly or indirectly by the electrical output of the generator. The controller selectively couples the energy storage component to the electrical bus, and the energy storage component is configured to store electricity provided by the generator, and to provide electricity to the working components by way of the electrical bus.

Abstract: A method of actively discharging a common bus (116) of a machine (100) having an engine (102), a generator (112), a traction motor (124) and one or more auxiliary devices (126) is provided. The method may monitor a speed of the engine (102) with respect to a first threshold, monitor a voltage of the common bus (116) with respect to a second threshold, and enable one or more of the generator (112), the motor (124) and the auxiliary devices (126) if the engine speed falls below the first threshold and the voltage exceeds the second threshold so as to discharge voltage from the common bus (116).

Abstract: A power converting device is disclosed that can reduce switching loss occurring in a voltage source inverter that drives an AC motor. It is possible to supply DC power to the voltage source inverter from both a voltage source rectifier, which converts AC power from an AC generator into DC power, and a battery. A first switching circuit is inserted between the voltage source rectifier and the AC generator, and the battery is connected to the output side of the voltage source rectifier. A second switching circuit is inserted between the battery and the voltage source inverter. A third switching circuit and a reactor are inserted in series between the input side of the voltage source inverter and the input side of the voltage source rectifier. At least one of an upper arm and a lower arm of the voltage source rectifier can be chopper controlled.