Abstract: Disclosed is a method for searching a MTPA curve of a vehicle permanent magnet synchronous motor based on a DC power, which includes a current closed-loop adjuster, a current command generator, a current command angle generator, an active power calculator, an active power storage and comparison processor and a current given vector corrector. According to the present disclosure, the tedious manual calibration is relieved, the optimal angle is automatically searched, and the production efficiency is improved; according to the present disclosure, the step size can be arbitrarily set according to the calibration requirements, so as to achieve a higher calibration accuracy.

Abstract: The present application relates to a control system and a method for controlling a passenger conveying apparatus, and a computer-readable storage medium for implementing the method. A control apparatus for a passenger conveying apparatus according to an aspect of the present application comprises: a processor; a memory coupled with the processor; a communication module coupled with the processor; and a computer program stored on the memory and running on the processor, the running of the computer program causes: in response to an internal control command of the control apparatus or an external control command outside the control apparatus, determining whether there is a passenger boarding signal in the passenger conveying apparatus within a specified time interval, wherein the internal control command and the external control command comprise commands for starting or stopping the passenger conveying apparatus; and manipulating the passenger conveying apparatus based on the determining.

Abstract: For improving Maximum Torque per Amps (MTPA) control, a method generates an offline MTPA curve based on an autotune test for a motor, which is used as offline MTPA control in order to run a motor at a high efficiency operation point. Another online method generates a search zone for the MTPA curve for a given torque point. The search zone includes an upper D-axis reference current and a lower D-axis reference current for the given torque point. The method iteratively modifies a D-axis reference current between the upper D-axis reference current and the lower D-axis reference current of the search zone. The method modifies a Q-axis reference current to output the given torque. The method updates a corresponding current pair of the given torque point to the modified D-axis reference current and the modified Q-axis reference current with a lowest current amplitude to improve MTPA control of the motor.

Abstract: An electric power tool includes: a brushless motor having a plurality of stator windings and configured to rotate in accordance with voltages applied to the plurality of stator windings, an induced voltage being generated in accordance with a rotation of the brushless motor; a rectifier circuit configured to rectify an AC voltage; a smoothing capacitor configured to smooth the AC voltage rectified by the rectifier circuit to a pulsation voltage having a maximum value larger than the induced voltage and a minimum value smaller than the induced voltage; and an inverter circuit configured to perform switching operations to output the pulsation voltage to the plurality of stator windings by rotation.

Abstract: A lifting device includes a motor designed as a three-phase asynchronous motor via which the lifting device can be driven to lift and lower a load, and includes a brake resistor via which a power output resulting from a motor generator operation that is carried out when lowering the load at a lowering speed can be converted into heat. The brake resistor is designed for a rated power which is less than the power resulting with a nominal load and a nominal speed. A method for operating a lifting device includes lowering a load at a lowering speed while taking into consideration at least one load capacity characteristic value of the brake resistor for the lowering speed, a threshold is set such that while lowering the load at the lowering speed corresponding to the threshold, the resulting power output is limited to the at least one load capacity characteristic value.

Abstract: An inverter-converter system includes a DC source, a DC to DC boost converter, a DC link capacitor, an inverter circuit, a variable speed electric machine, and a controller. The DC to DC boost converter receives an input DC voltage from the DC source. The inverter circuit converts the variable boosted voltage to an AC voltage to drive the variable speed electric machine. The controller senses a plurality of parameters from the variable speed electric machine, and controls the DC to DC boost converter to boost up the input DC voltage to a variable output voltage based on the plurality of parameters and/or the voltage (or load) needed by the variable speed electric machine. The design of the inverter-converter system can achieve an electrical efficiency and cost savings for the overall system.

Abstract: A vehicular opening/closing body control device includes a braking control unit configured to apply a braking force to an opening/closing body by supplying driving power having a locked conduction phase to a motor, which is a drive source of the opening/closing body, wherein, when an execution time of phase-locked conduction control for locking the conduction phase and supplying the driving power reaches or exceeds a predetermined time, the braking control unit switches a conduction phase used for the phase-locked conduction control.

Abstract: Systems and methods are disclosed for determining an operating point for controlling an electric motor. An exemplary system may include a voltage monitor configured to determine a voltage applied to the electric motor. The system may also include a controller configured to determine the operating point based on the voltage. The controller may include a comparator configured to determine a difference between the voltage and a reference voltage. The controller may also include a regulator configured to generate a correction signal for reducing the difference. The controller may be configured to determine the operating point when the difference is below a predetermined threshold.

Abstract: A washing machine includes an alternating current (AC) motor which generates torque, a clutch assembly which selectively transfers the torque to a rotating tub and a pulsator, a speed detector which detects a rotary speed of the clutch assembly, and a controller configured to repetitively perform operating and stopping the operating of the AC motor based on a predetermined target speed and the rotary speed of the clutch assembly in a spin-drying operation. The controller gradually increases the torque of the AC motor while operating the AC motor.

Abstract: The present disclosure relates to a motor protection relay and a method for starting a motor of the motor protection relay, and particularly, to a motor protection relay capable of softly starting a motor, without a separate starting device, and performing soft starting of the motor more stably, effectively, and simply, by variably controlling start power for starting the motor to the motor through controlling of the relay itself and supplying the variably controlled start power to the motor, and a method for starting a motor thereof.

Abstract: The present invention discloses a current balancing device and method capable of balancing an output current and an input current of a current loop. Said device comprises: a transmission circuit for outputting an output current and receiving an input current; at least one adjustable resistor set in the current loop for providing resistance according to at least one adjustment signal; and a current balancing circuit, coupled to the transmission circuit and the adjustable resistor, for determining whether the difference between the output and input currents satisfies a predetermined requirement in light of a predetermined duration and thereby generating the adjustment signal, wherein if the difference between the output and input currents fails to satisfy the predetermined requirement, the current balancing circuit will adjust the resistance of the adjustable resistor through the adjustment signal, so as to reduce the difference between the output and input currents.

Abstract: A method of obtaining a maximum magnetic flux of a permanent magnet synchronous motor may comprise: receiving a first command voltage from a current controller to control current applied to the permanent magnet synchronous motor; receiving an on/off duty ratio of a control pulse signal to control an output voltage of an inverter that drives the permanent magnet synchronous motor, the on/off duty ratio being determined based on the first command voltage; generating a second command voltage corresponding to the output voltage to be output from the inverter based on the on/off duty ratio of the control pulse signal; obtaining a maximum command voltage error by comparing the first and second command voltages; and/or obtaining the maximum command magnetic flux of the permanent magnet synchronous motor according to a position of a rotor of the permanent magnet synchronous motor based on the maximum command voltage error.

Abstract: Disclosed herein is an apparatus of a sensorless brush less direct current (BLDC) motor capable of rapidly driving the BLDC motor at a decreased speed.

Abstract: The invention relates to an asynchronous motor unit including a frequency converter for regulating the asynchronous motor. The frequency converter comprises an input-side, uncontrolled bridge rectifier, a DC voltage intermediate circuit and an output-side inverter. According to the invention, the DC voltage intermediate circuit furthermore comprises a DC-to-DC converter with galvanic isolation, with the result that electrical isolation between the bridge rectifier and the inverter is produced.

Abstract: An electric braking control apparatus for controlling an electric braking apparatus which includes a brake pad, a motor which generates a rotational torque, and a rotation/linear motion conversion mechanism which causes the brake pad to generate a pressing force based on the torque. The braking control apparatus includes an inverter which converts and outputs an electric current supplied from a power supply to the motor, and a microcomputer that receives power from the power supply, detects the value of a voltage applied from the power supply to the inverter, and controls the electric current output from the inverter depending on a result of the detection.

Abstract: Apparatus for transferring power between an electricity network (UP) operating on alternating-current electricity and a multiphase electric machine (M2, M3), which apparatus comprises low-voltage power cells (CS, C11 . . . CN6) operating on a cascade principle, which power cells comprise a single-phase output connector (OUT), and at least one transformer (TA, T1 . . . TN), comprising for each power cell connected to it a single-phase or multiphase winding dedicated to the specific power cell, which transformer comprises at least one additional winding (WA, WB1 . . . WBN) connected to the same magnetic circuit as the other windings for the purpose of at least one auxiliary circuit, which can be connected to the aforementioned additional winding.

Abstract: A system and method for determining the holding torque of a brake in a material handling system is disclosed. The material handling system may include a bridge, a trolley, and a hoist, each driven along a different axis by a motor. A brake is operatively coupled to the motor to prevent unwanted motion of the motor. A motor controller is coupled to each motor which controls operation of the motor and its corresponding brake. The motor controller generates a torque command to the motor while keeping the brake set. The initial torque command is less than the holding torque of the brake. The torque command is incremented until motion is detected on the motor. The torque value when motion is detected is stored in the motor controller and displayed to an operator.

Abstract: A drive motor control apparatus for a vehicle, wherein the vehicle has a motor and rotation detecting unit. In the apparatus, the first difference computing unit computes one of multiple first differences every time an actual detected angle of rotation of the motor becomes a corresponding representative angle during the one cycle. The first difference indicates an advancing amount of an estimated angle relative to the actual detected angle. The second difference computing unit computes multiple second differences based on the first differences of the one cycle. The second differences are adjusted in accordance with a degree of acceleration and deceleration of the motor. The adjusted second differences are used for correcting the actual detected angle of rotation of the motor.

Abstract: A method of braking a washing machine from an operational speed to a reduced non-zero speed is provided (as well as a washing machine incorporating the method) for a washing machine driven by one of a synchronous or asynchronous motor. Upon receipt of a speed reduction signal, the motor rotating magnetic fields are collapsed for a defined time period. After the defined time period, DC braking voltage is applied to the motor stator windings at a controlled ramp-up rate to an amplitude to generate a controlled ramped braking torque on the motor until the motor has slowed to a defined reduced speed. Thereafter, the amplitude of the DC braking voltage is set to 0V and the motor is soft started to an amplitude and reduced frequency needed to maintain the defined reduced speed.

Abstract: The invention relates to a switch arrangement of an electric motor drive (1). The electric motor drive comprises safety switches (3) determined by the safety of the drive, a controlled mechanical brake (4), a power supply circuit (5) of the brake control, a power converter (6), which power converter comprises a network rectifier (7) and a power rectifier (8) of the motor. The power rectifier of the motor is at least partly implemented with controlled semiconductor switches (9, 10) arranged into a bridge. The power converter comprises an intermediate circuit (11, 12) between the network rectifier and the power rectifier of the motor. The switch arrangement comprises normally-open switches (13, 14) in the intermediate circuit of the power converter (6).

Abstract: A DC motor control device calculates motor speed using determinations of motor field flux and armature voltage in the motor. The device includes a control module having one or more control inputs and one or more control outputs. At least one control input is configured to receive data representing field current measured in the DC motor. The control module includes flux curve logic that is responsive to measurements of motor field current to calculate a field flux in the motor. The flux curve logic uses a flux curve stored in the control module, the flux curve representing a functional relationship between field current and field flux in the motor. The flux curve is defined by a plurality of flux curve data points corresponding to a plurality of motor field currents within a lower current range and within an upper current range. The flux curve is further defined by at least a first flux curve line positioned within the lower current range and a second flux curve line positioned within the upper current range.

Abstract: A servomotor system is provided. The servomotor system includes an enclosure and a motor stator and rotor disposed in the enclosure. The servomotor system also includes a motor brake disposed in the enclosure and configured to selectively brake the rotor from rotation and a brake control switch disposed in the enclosure and coupled to the motor brake for selectively providing power to the motor brake for selectively engaging and/or disengaging the brake.

Abstract: A method of operating a motor, the method comprising: operating a motor at a first speed; operating the motor in negative slip; imbalancing at least one phase of the motor to dissipate regeneration energy using windings of the motor; and wherein a next motor speed is decreased to a speed less than the first speed. An apparatus for carrying out the method is also presented.

Abstract: A slip frequency is estimated from a current instruction or detected currents in an induction motor. Acceleration impossibility in an induction motor drive unit is determined, when the slip frequency exceeds the maximum torque generating slip frequency for the predetermined interval or the time integrating result exceeds a predetermined value; when the q-axis magnetic flux exceeds the maximum torque generating q-axis magnetic flux or exceeds for a predetermined interval; when the estimated rotational speed is under a predetermined value; when the rotational speed variation rate is negative; and when the rotational speed instruction value or the estimated rotational speed is equal to or smaller than a predetermined value. An induction motor drive system and an elevating system including the induction motor drive unit are also disclosed.

Abstract: A boost converter boosts a DC voltage of a DC power supply. An inverter converts the output voltage of the boost converter into an AC voltage. A control device that controls the boost converter reduces an output voltage instruction value of the boost converter when the rotation speed of the AC motor decreases and an absolute value of a variation rate of the rotation speed is not less than a predetermined value. The inverter is controlled in the control mode selected from a plurality of control modes including three modes of a sine wave PWM control mode, an overmodulation PWM control mode and a rectangular wave control mode. The control device of the boost converter reduces the output voltage instruction value of the boost converter only when the control mode of the inverter is the rectangular wave control mode or the overmodulation control mode.

Abstract: A motor driving apparatus for driving and braking a motor equipped with a brake comprises a motor/brake driving DC power supply which is used both as a motor driving power supply and as a brake driving power supply, wherein when the motor/brake driving DC power supply is being used as the motor driving power supply, a voltage conversion circuit via which a voltage supplied from the motor/brake driving DC power supply is applied to the brake feedback-controls the voltage applied to the brake. This configuration serves to reduce the loss (due to temperature rise) in the brake coil of the motor being driven to move a robot arm.

Abstract: In the m phase brushless generator, n (n<m) phase magnet coil groups are provided with magnetic sensors, while the remaining (m?n) phase magnet coil groups are not provided with magnetic sensors. The regeneration control circuit utilizes the sensor outputs of the n magnetic sensors to generates n sets of regeneration control signals for the n phase magnet coil groups. The regeneration control circuit further generates (m?n) sets of regeneration control signals for the (m?n) phase magnet coil groups not associated with the n magnetic sensors, using one or more of the sensor outputs of the n magnetic sensors in generation of each of the (m?n) sets of regeneration control signals.

Abstract: A system and method are provided whereby at least two motors driven by an inverter coupled to a DC bus are configured to alternate between regenerative and injection braking such that at least one motor is placed in regenerative braking mode and at least one motor is placed in motoring mode. Energy is simultaneously placed on and removed from the DC bus in a manner allowing a large current to flow in as many motors as possible, for fast stoppage of load inertia. At least one motor may be placed in regenerative braking mode and at least one motor in DC injection mode, such that energy is simultaneously placed onto and removed from the DC bus, respectively. Further, a single motor may be is alternated between regenerative braking and DC injection braking, such that energy is alternately placed onto and removed from the DC bus, respectively.

Abstract: A slip frequency is estimated from a current instruction or detected currents in an induction motor. Acceleration impossibility in an induction motor drive unit is determined, when the slip frequency exceeds the maximum torque generating slip frequency for the predetermined interval or the time integrating result exceeds a predetermined value; when the q-axis magnetic flux exceeds the maximum torque generating q-axis magnetic flux or exceeds for a predetermined interval; when the estimated rotational speed is under a predetermined value; when the rotational speed variation rate is negative; and when the rotational speed instruction value or the estimated rotational speed is equal to or smaller than a predetermined value. An induction motor drive system and an elevating system including the induction motor drive unit are also disclosed.

Abstract: A washing machine is provided that includes an induction motor and a motor control circuit with a feedback loop. The feedback loop provides rotor speed to a microprocessor of the motor control circuit. The motor control circuit and feedback loop control the motor such that the motor operates in a negative slip mode which provides braking to the washing machine.

Abstract: A drive, including at least a brake and an electromotor, is connected to an output stage with the aid of supply lines, the brake being supplied from a brake control, the brake control being connected to the supply lines for its supply, via capacitors.

Abstract: A drive system with an electric motor is described, which includes an integrated armature short-circuit brake and a mechanical brake. If the electric motor cannot be controllably slowed down, a control signal is applied at an activation time to the integrated armature short-circuit brake and the mechanical brake, and the armature short-circuit brake is switched off when reaching a thermal load limit for the electric motor or the control electronics.

Abstract: A method and apparatus for stopping an AC motor that is controlling a load while detecting mechanical brake slippage of a mechanical brake for holding the load against movement includes a controller for decreasing torque-producing current commands from the drive while a speed regulator is commanding zero speed, sensing movement of the load while the speed regulator is commanding zero speed, detecting movement of the load past a pre-determined distance limit, and increasing torque to support the load and prevent further movement of the load. The controller will again decrease torque-producing current commands from the drive, and again checking for movement of the load, and upon sensing no load movement upon reaching zero torque, then shutting off the motor.

Abstract: A method for rotating a printer paper-feed roller wherein the roller is driven by a DC (direct current) motor. A feedback-control signal is applied to the motor until the roller reaches a desired rotational position. The feedback-control signal is a function of an error signal, and the error signal represents the difference between the actual rotational position and the desired rotational position of the roller. When the roller reaches the desired rotational position, the applied feedback-control signal is removed from the motor, and a direct-control biasing signal is applied to the motor to reduce or prevent rollback of the roller when the feedback-control signal is removed from the motor. In one example, the signals are PWM (pulse-width-modulated) signals.

Abstract: A motor power supply including a DC supply part having a pair of supply terminals; an inverter having a pair of connection terminals respectively connected to the supply terminals thereof to receive DC power therefrom and to supply AC power to a motor, a breaking resistor and a control switching element disposed in parallel in an additional line connecting the pair of connection terminals to each other, a control switching element disposed with the breaking resistor in the additional line, a breaking switch disposed to one of the connection terminals and switched to either a normal position or a breaking position connecting the one connection terminal to a corresponding supply part or to the additional line, a speed detector detecting a motor speed and a control part controlling the breaking switch to switch to the breaking position and controlling the control switching element so that an on-off interval of the control switching element is controllable depending on the detected speed.

Abstract: A control system for an electric machine includes a flux weakening module, which includes a voltage magnitude calculator that receives d-axis and q-axis command voltages and that generates a voltage magnitude. An error circuit compares the voltage magnitude to a reference voltage and generates an error signal. A controller receives the error signal and generates a feedback flux correction signal. A limiter limits the feedback flux correction signal to a predetermined flux value and generates a limited feedback flux correction signal. A feedforward stator flux generating circuit generates a feedforward stator flux signal. A summing circuit sums the feedforward stator flux signal and the limited feedback flux correction signal to generate a final stator flux command.

Abstract: An apparatus for controlling deceleration of a DC motor which is driven in a forward operating direction with a forward-drive electric current applied thereto by a forward driving device, wherein the forward motor driving device applies the forward-drive electric current in the form of pulses to the DC motor during its deceleration, and wherein a plugging-braking device operable while the motor is subjected to a regenerative brake or operated in a non-braked state is operated to apply a reverse-drive electric current in the form of pulses to the motor, to apply a plugging brake to the motor, such that at least one pulse of the reverse-drive electric current follows every predetermined number of pulses of the forward-drive electric current.

Abstract: A device to control a 3-phase motor having an inverter connected to each phase terminal and a brake to arrest the 3-phase motor, includes a power supply to supply power to the brake and the inverter at the same time based on a predetermined synchronization signal. The device also includes a control unit to output an inverter control signal to control the inverter and a power control signal to enable the power supply to supply the power to the brake and the inverter. Thus, the device to control a 3-phase motor has an immediate response to a control signal with a reduced production cost and a system size, by reducing circuit components such as a brake relay and a brake power supply.

Abstract: A driving apparatus of a three-phase induction motor includes: a three-phase power supply unit for supplying three-phase power; a rectifier for rectifying the three phase voltage supplied from the three phase power supply unit; a voltage reducing unit for reducing a DC voltage generated from the rectifier and outputting a stabilized DC voltage; and an inverter unit for varying the DC voltage outputted from the voltage reducing unit to a three-phase AC voltage and driving a three-phase induction motor. A power-factor degradation generated during supplying a DC voltage to the inverter to drive the three-phase induction motor is prevented, a harmonic wave is removed, and because a high-priced inverter component is not necessary, its relevant expense is reduced.

Abstract: An inverter part having a switching unit for applying a three-phase AC voltage to a motor, a lock detection unit for detecting a lock state of the motor and also generating a lock detection signal by the detection, and a current control unit for passing a d-shaft armature current id through the motor so that an absolute value of a current of a phase with the largest current flowing through the motor decreases based on the lock detection signal.

Abstract: A control method and a switching circuit for braking an electronically commutated electrical motor, wherein operation is in a phase period (T) of an inverter relative to at lest one winding, sequentially, both in a motoring mode and a generating operating mode using various cycles (t1-t2, t3-t4) beginning with zero, such that the driving and braking torques associated with the cycles (t1-t2, t3-t4) produce a resultant braking moment averaged over the phase period (T).

Abstract: A circuit configuration supplies an electric motor with a stator and a rotor. The stator has a large number of electromagnets, arranged in particular in the form of a ring, and the rotor has a large number of permanent magnets that are associated with the electromagnets on the stator and are arranged, in particular, in the form of a ring. A rectifier circuit converts the a.c. voltage which is drawn from the supply network to a d.c. voltage. A converter circuit converts the d.c. voltage to a controllable frequency a.c. voltage for supplying the electric motor with electrical drive energy. An energy storage circuit which contains at least one accumulator is connected between the rectifier circuit and the converter circuit.

Abstract: PWM AC power is supplied to an induction motor or other AC load. The frequency and magnitude of the waveforms is controlled by detecting the peak voltage or width of the reverse EMF pulses at the commencement of the power waveform applied to the load, and then adjusting the applied AC power based on the detected peak voltage or width. Alternatively, the depth of width of a notch that follows the reverse EMF pulse can be detected and used to control the applied AC power.

Abstract: This invention is to provide a variable speed apparatus capable of equalizing a moving distance at the time of deceleration from deceleration start to deceleration completion in the case that a deceleration stop command is inputted during acceleration to a moving distance at the time of deceleration from deceleration start to deceleration completion in the case that a deceleration stop command is inputted during operation at an adjustable speed reference frequency even when the deceleration stop command is inputted during acceleration.

Abstract: In order to control the run-down of an induction machine, whose stator is connected to a singe-phase or polyphase AC main power supply system via an AC power controller which can be controlled by phase gating, a phase gating angle is first increased in steps until an operating point is reached, which is defined on the basis of predetermined criteria. The phase gating angle is then controlled in order to ensure that the induction machine runs down in accordance with a predetermined control program.

Abstract: A multi-functional hybrid contactor has a motor protection function against an abnormal state in addition to the starting, running and stopping of the motor, the same effect as the case that an electronic motor protection relay (EMPR) is connected in parallel can be obtained with only one multi-functional hybrid contactor. Also, the size of the product is much reduced compared to the case that the electric motor protection relay (EMPR) is connected in parallel, and its cost can be reduced. In addition, since the semiconductor switch is turned on only in the initial stage of starting and stopping, the rated current capacity and size of the semiconductor switch can be considerably reduced compared to the conventional soft starting method in which the semiconductor switch is used for controlling of all of starting, running and stopping.

Abstract: A control device for a compressor motor and an inverter according to the present invention monitors the amplitude of a phase current of a three-phase DC motor. As the amplitude of the phase current approaches an overload condition of the inverter or motor, the control device decreases the rotational velocity of the motor by a predetermined rotational deceleration. By reducing the rotational velocity of the motor by a certain deceleration, the control device of the present invention ensures that the motor load, i.e., the amplitude of the phase current, does not reach or exceed an overload condition. By use of this device, it is possible to suppress or reduce effectively the frequency of motor stops caused by an increase in the phase current.

Abstract: A power tool including a braking and control circuit. The braking and control circuit includes a microcontroller-based control means circuit. The microcontroller assures control of switch means, such as triacs, switches and relays, and ensures that braking is effectuated regardless of the phase in the power cycle of the alternating current. Also, the microcontroller is programmable so that the braking and control circuit accommodates different braking conditions for different power tools and accommodates combinations of braking conditions for the same power tool. Further, the microcontroller is programmable to configure the braking and control circuit so that the braking force applied to the motor and the stopping time of the motor are regulated and adjustable. This may be accomplished by outputting a control signal so that the switch means skips cycles in the alternating current or by otherwise adjusting the operation of the switch means.

Abstract: The present invention relates to a system for controlling the rotation speed of AC motors, in particular single phase motors. In this case, a controllable electronic switching device is connected upstream of the motor and is actuated by a control unit such that a sinusoidal input AC voltage is used to produce a motor AC voltage which can be varied in order to change the rotation speed. The control unit is designed in such a manner that the fundamental frequency and/or the amplitude of the motor AC voltage can be varied by phase gating.

Abstract: While a ring gear shaft 126 linked with a drive shaft rotates, a power output apparatus 110 applies a torque to a first motor MG1 attached to a sun gear shaft 125, thereby abruptly increasing a revolving speed of an engine 150, to which a fuel injection is stopped. A torque generated by a frictional force of, for example, a piston in the engine 150 and working as a reaction is applied as a braking torque to the ring gear shaft 126 via a planetary gear 120. The magnitude of the braking torque depends upon the frictional force of, for example, the piston and can be controlled by regulating the revolving speed of the engine 150 by means of the first motor MG1. This control procedure enables the energy consumed by the engine 150 to be output as a braking force to the drive shaft.