JP2012228138A - Vehicle drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle drive device capable of generating audible sound of adequate sound pressure level in a simple configuration.SOLUTION: An electric vehicle drive device employs a motor generator MG as a motor for driving a vehicle. When the motor generator MG performs a control action, an electric current containing ripple component flows across the motor generator MG. The electric vehicle drive device generates an approach alarm sound that notifies a pedestrian that a vehicle is approaching by resonating a mechanical vibration generated on the motor generator MG by the electromagnetic force derived from the ripple component, with the component member or the peripheral member of the motor generator MG. The electric vehicle drive device sets a carrier frequency of an inverter 12 in accordance with the vehicle running state, and causes a member, among a plurality of motor generator component members and a plurality of peripheral members, whose eigen frequency meets the frequency of the ripple component to generate an approach notification sound.

Description

  The present invention relates to a vehicle drive device, and more particularly to an improvement in a device that generates an audible sound based on switching control of a motor.

  Hybrid vehicles that use an engine and a motor are widely used. In general, a hybrid vehicle travels by the driving force of a motor until the vehicle speed reaches a predetermined speed. The engine is started when the vehicle speed reaches a predetermined speed, when the accelerator pedal operation amount exceeds a predetermined amount, or when the charge amount of the secondary battery decreases, and the combined drive of the motor and engine It travels with power or engine driving force. The driving force of the engine is used not only for driving the vehicle but also for driving a generator provided for charging the secondary battery. In addition to such hybrid vehicles, electric vehicles that run using a motor are widely used.

  Vehicles such as hybrid cars and electric cars have low noise during low-speed running. Therefore, in these vehicles, it may not be easy for pedestrians and bicycle users to recognize the approach of the vehicle by hearing, compared to conventional engine-driven vehicles. In view of this, research and development of vehicles that generate notification sounds according to driving conditions, driving operations, and the like are widely performed.

  Patent Document 1 describes a vehicle presence notification device. In this apparatus, an ultrasonic wave modulated by an audible sound is radiated from a speaker mounted on the vehicle, and a sound heard by a pedestrian is changed according to a distance from the vehicle. Patent Document 2 describes an electric vehicle control device. In this apparatus, an electromagnetic sound accompanying switching control is generated from an electric motor. Further, electromagnetic noise is generated even when the electric motor is stopped by the control of the inverse conversion unit that controls the electric motor. Cited Document 3 describes a vehicle equipped with a prime mover and a motor. In this vehicle, control is performed so as to eliminate the uncomfortable feeling between the driving operation and the sense of sound in the passenger compartment. As one of the controls, there is described what changes the carrier frequency of the drive circuit for driving the assist motor in accordance with the driving operation and changes the frequency of the sound emitted from the drive circuit in accordance with the driving operation. Cited Document 4 describes a control device for a vehicle motor. In this apparatus, the electric current supplied from the inverter to the motor is controlled to generate electromagnetic noise by the motor. Then, the frequency or magnitude of the electromagnetic sound is changed according to the running state of the vehicle.

JP 2010-215021 A JP 2010-93908 A JP 9-46819 A JP 2005-130614 A

  The device described in Patent Document 1 requires a device for generating a notification sound in addition to a device for driving the vehicle. Therefore, this apparatus has a problem that the number of parts mounted on the vehicle increases. Further, in the devices described in the cited documents 2 to 4, the switching frequency of the circuit for driving and controlling the motor is lowered to such an extent that the electromagnetic sound or the vibration sound of the circuit becomes an audible sound. However, the devices described in these cited documents cannot always easily generate an audible sound having a sufficient sound pressure level.

  The present invention has been made for such a problem. That is, an object of the present invention is to provide a vehicle drive device that generates an audible sound having a sufficient sound pressure level with a simple configuration.

  The present invention includes a motor that drives a vehicle, an inverter that supplies electric power according to switching control to the motor, and a control unit that performs switching control on the inverter, and the motor has a current flowing through itself. When the frequency of the ripple component coincides with its own natural frequency, an audible sound due to resonance is generated, and the control unit controls the frequency of the ripple component by adjusting the carrier frequency when performing switching control. It is characterized by that.

  In addition, the vehicle drive apparatus according to the present invention preferably includes a peripheral member that is used together with the motor and generates an audible sound due to resonance when the frequency of the ripple component matches its own natural frequency.

  In addition, the present invention is used together with the motor that drives the vehicle, an inverter that supplies power corresponding to switching control to the motor, a control unit that performs switching control on the inverter, and flows to the motor. A peripheral member that generates an audible sound due to resonance when the frequency of the ripple component of the current and its own natural frequency coincide with each other, and the control unit adjusts the carrier frequency when performing switching control, The frequency of the ripple component is controlled.

  Further, in the vehicle drive device according to the present invention, preferably, the motor has a plurality of different natural frequencies, and the control unit adjusts a carrier frequency to any one of the plurality of natural frequencies. The frequency of the ripple component is matched.

  The vehicle drive device according to the present invention preferably includes a plurality of the peripheral members having different natural frequencies, and the control unit adjusts a carrier frequency and a plurality of natural vibrations based on the plurality of peripheral members. The frequency of the ripple component is matched with any of the numbers.

  In addition, the vehicle drive device according to the present invention preferably includes a plurality of the peripheral members having different natural frequencies, the motor has a plurality of different natural frequencies, and the control unit sets a carrier frequency. And adjusting the frequency of the ripple component to one of a plurality of natural frequencies based on the motor and the plurality of peripheral members.

  In the vehicle drive device according to the present invention, preferably, the control unit selects one of a plurality of frequencies determined corresponding to the plurality of natural frequencies according to the speed of the vehicle. Set the carrier frequency to the selected frequency.

  In the vehicle drive device according to the present invention, preferably, the control unit controls acceleration of the vehicle at any one of a plurality of frequencies determined corresponding to the plurality of natural frequencies. Select according to the state of the part, and set the carrier frequency to the selected frequency.

  In the vehicle drive device according to the present invention, preferably, the acceleration control unit includes an accelerator pedal, and is higher than a previously selected frequency according to a comparison between an operation amount of the accelerator pedal and a predetermined threshold value. Select the frequency.

  ADVANTAGE OF THE INVENTION According to this invention, the vehicle drive device which generate | occur | produces the audible sound of sufficient sound pressure level by simple structure can be provided.

It is a figure which shows the structure of the electric vehicle drive device which concerns on embodiment of this invention. It is a figure which shows the structural example of an inverter. It is a figure which shows the structure of an inverter control part. It is a flowchart of frequency control of approach notification sound. It is a figure which shows the relationship between a vehicle speed and a carrier frequency. It is a flowchart of application control. It is a figure which shows the example of a change of a carrier frequency. It is a figure which shows the structure of the hybrid vehicle drive device which concerns on embodiment of this invention.

  FIG. 1 shows a configuration of an electric vehicle driving apparatus according to an embodiment of the present invention. This apparatus uses a motor generator MG as a vehicle driving motor. With the control of the motor generator MG, a current including a ripple component flows through the motor generator MG. The electric vehicle drive device resonates the constituent members of the motor generator MG or its peripheral members with mechanical vibrations generated in the motor generator MG by the electromagnetic force based on the ripple component, thereby approaching the pedestrian of the approach of the vehicle. A notification sound is generated.

  The configuration and travel control of the electric vehicle drive device will be described. The DC power supply circuit 10 includes a secondary battery that can be repeatedly charged and discharged, and outputs a DC voltage to the inverter 12 via the positive electrode transmission line P and the negative electrode transmission line N. For example, a circuit that includes a DC / DC converter that boosts the voltage of the secondary battery and outputs the boosted DC voltage is used as the DC power supply circuit 10.

  When accelerating the vehicle, the inverter 12 converts DC power based on the voltage output from the DC power supply circuit 10 into three-phase AC power, and the three-phase AC power is converted into a motor via power transmission lines U, V, and W. Output to generator MG. Motor generator MG generates torque based on the three-phase AC power output from inverter 12 and applies the generated torque to torque transmission mechanism 14. Torque transmission mechanism 14 transmits the torque applied from motor generator MG to wheels 16. This accelerates the vehicle.

  Inverter 12 acquires the three-phase AC power generated by motor generator MG via power transmission lines U, V, and W when the vehicle is regeneratively braked. Then, the acquired three-phase AC power is converted into DC power, and the DC power is output to the DC power supply circuit 10 via the positive transmission line P and the negative transmission line N. The DC power supply circuit 10 performs charging based on the DC power output from the inverter 12. Thus, motor generator MG generates braking torque and charges a secondary battery included in DC power supply circuit 10. Torque transmission mechanism 14 brakes wheel 16 by the braking torque of motor generator MG. This decelerates the vehicle.

  The driving operation unit 20 includes an accelerator pedal, a brake pedal, an operation panel provided at the driver's seat, and the like, and gives information related to driving operation to the control unit 18. Motor generator MG includes a resolver 22 that detects the number of rotations thereof. The resolver 22 outputs the rotation speed detection value to the control unit 18. The control unit 18 controls the DC power supply circuit 10 and the inverter 12 based on the detection value of the resolver 22, information related to the driving operation, and the like. The DC power supply circuit 10 adjusts the DC voltage output to the inverter 12 according to the control of the control unit 18. Inverter 12 performs DC-AC conversion between DC power supply circuit 10 and motor generator MG, and adjusts power transferred between DC power supply circuit 10 and motor generator MG based on the control of control unit 18. To do.

  FIG. 2 shows a configuration example of the inverter 12. This circuit comprises three sets of IGBTs 24u, 24v and 24w, each including an upper IGBT 24-1 and a lower IGBT 24-2. The emitter terminal of the upper IGBT 24-1 in each IGBT group is connected to the collector terminal of the lower IGBT 24-2 in the same group. A diode 24-3 is connected between the collector terminal and emitter terminal of each IGBT so that the emitter terminal side becomes an anode terminal.

  The collector terminals of the upper IGBT 24-1 of each IGBT set are connected in common, and are connected to the positive transmission line P from the DC power supply circuit 10. The emitter terminals of the lower IGBT 24-2 of each IGBT set are connected in common and are connected to the negative electrode transmission line N from the DC power supply circuit 10.

  A connection node between the upper IGBT 24-1 and the lower IGBT 24-2 of the IGBT set 24u is connected to the power transmission line U of the motor generator MG. The connection node between the upper IGBT 24-1 and the lower IGBT 24-2 of the IGBT set 24v is connected to the power transmission line V of the motor generator MG, and the connection node between the upper IGBT 24-1 and the lower IGBT 24-2 of the IGBT set 24w. Is connected to the power transmission line W of the motor generator MG.

  Here, an example is shown in which an IGBT is used as the switching element of the inverter 12, but other semiconductor elements such as a thyristor, a triac, a bipolar transistor, and a field effect transistor may be used as the switching element.

  Control unit 18 performs switching for upper IGBT 24-1 and lower IGBT 24-2 included in each IGBT set, and causes inverter 12 to perform DC-AC conversion between DC power supply circuit 10 and motor generator MG.

  An example of an inverter control unit configured inside the control unit 18 for controlling the inverter 12 of FIG. 2 is shown in FIG. Command signal generation unit 28 outputs AC voltage command values Vu, Vv, and Vw to subtractors 30u, 30v, and 30w, respectively. This AC voltage command value defines the AC voltage output from the inverter 12.

  The triangular wave signal generation unit 26 outputs a triangular wave signal as a carrier signal to the subtracters 30u, 30v, and 30w. The frequency of this triangular wave signal is called a carrier frequency. The subtractor 30u outputs a signal obtained by subtracting the triangular wave signal from the AC command voltage Vu to the driver 32u. When the signal output from the subtractor 30u is negative, the driver 32u outputs a signal for turning on the upper IGBT of the IGBT set 24u to the upper IGBT and a signal for turning off the lower IGBT of the IGBT set 24u. Output to the lower IGBT. On the other hand, when the signal output from the subtractor 30u is 0 or positive, the driver 32u outputs a signal for turning off the upper IGBT of the IGBT set 24u to the upper IGBT and turns on the lower IGBT of the IGBT set 24u. Is output to the lower IGBT.

  The subtractor 30v and the driver 32v each output a signal for controlling the IGBT set 24v by a process similar to the process executed by the subtractor 30u and the driver 32u. The subtractor 30w and the driver 32w A signal for controlling the IGBT set 24w is output by a process similar to the process executed by the driver 32u.

  With such a configuration, the inverter 12 performs DC-AC conversion between the DC power supply circuit 10 and the motor generator MG. That is, the inverter 12 converts the DC power output from the DC power supply circuit 10 into three-phase AC power and outputs it to the motor generator MG according to the switching control, or the three-phase AC output from the motor generator MG. The power is converted into DC power and output to the DC power supply circuit 10.

  Next, an operation in which the electric vehicle driving device generates an approach notification sound will be described. The current flowing through each of power transmission lines U, V, and W of motor generator MG includes a ripple component based on switching control of inverter 12. The electric vehicle drive device generates an audible sound as an approach notification sound by using mechanical vibration generated in the motor generator MG by an electromagnetic force based on the ripple component.

  When switching control for the inverter 12 shown in FIG. 2 is performed by the inverter control unit shown in FIG. 3, the frequency of the ripple component of the current flowing through each power transmission line is twice the carrier frequency. .

  The stator windings of each phase of motor generator MG mechanically vibrate due to electromagnetic force based on the ripple component of the current flowing through the motor generator MG. When the frequency of the ripple component is a frequency within the audible frequency band, the stator winding generates an audible sound based on mechanical vibration. Furthermore, when the frequency of the ripple component is matched with the natural frequency of the stator winding by setting the carrier frequency, the mechanical vibration of the stator winding increases due to the resonance phenomenon. As a result, the stator winding generates an audible sound having a sufficient sound pressure level as an approach notification sound.

  Further, the mechanical vibration of the stator windings is transmitted to a constituent member of the motor generator MG (hereinafter referred to as a motor generator constituent member) such as a housing, a rotor, and a shaft of the motor generator MG. Further, the mechanical vibration of the stator winding is also transmitted to the peripheral members of the motor generator MG such as the torque transmission mechanism 14 to which the shaft of the motor generator MG is attached and the components provided in the motor generator MG.

  In addition to the stator winding, there is a rotor as a member that is a source of mechanical vibration. For example, the rotation speed of motor generator MG varies according to the frequency of the ripple component of the current flowing in the stator winding. Such rotational vibration is transmitted to a rotor, a shaft and the like of the motor generator MG. Furthermore, the rotational vibration is also transmitted to components provided in the torque transmission mechanism 14 and the motor generator MG.

  Therefore, when the frequency of the ripple component is matched with the natural frequency of the motor generator constituent member by setting the carrier frequency, the mechanical vibration of the motor generator constituent member increases due to the resonance phenomenon. When the frequency of the ripple component is matched with the natural frequency of the peripheral member, the mechanical vibration of the peripheral member increases due to the resonance phenomenon. As a result, the motor generator component member or the peripheral member generates an audible sound having a sufficient sound pressure level as an approach notification sound. Therefore, the approach notification sound can be generated by the existing parts conventionally used in the electric vehicle drive device without newly adding a part for generating the approach notification sound.

  In addition to the above, the peripheral members include a casing that houses the DC power supply circuit 10 and the inverter 12, parts that constitute the DC power supply circuit 10, parts that constitute the inverter 12, and the like. Moreover, the torque transmission mechanism 14 is comprised with a gear, a shaft, a housing | casing, etc., and these components can also be a peripheral member which generate | occur | produces an audible sound. When a transaxle is configured as a part of the torque transmission mechanism 14, the transaxle can also be a peripheral member that generates an audible sound.

  The electric vehicle drive device according to the present embodiment generates approach notification sounds having different frequencies according to the traveling state. The principle will be described below. The electric vehicle drive device includes a plurality of motor generator components and a plurality of peripheral members. The plurality of motor generator constituting members and the plurality of peripheral members have different natural frequencies. When the frequency of the ripple component is matched with the natural frequency of any of the plurality of motor generator constituent members and the plurality of peripheral members by setting the carrier frequency, there is a member whose natural frequency matches the frequency of the ripple component. An audible sound is generated as an approach notification sound.

  Therefore, the electric vehicle drive device sets a carrier frequency according to the running state of the vehicle, and approaches the member whose natural frequency matches the frequency of the ripple component among the plurality of motor generator constituent members and the plurality of peripheral members. Generate sound. By such frequency control, approach notification sounds having different frequencies can be generated according to the running state.

  FIG. 4 shows a flowchart of frequency control of approach notification sound. In the control based on this flowchart, the first frequency in the audible frequency band matches the natural frequency of one of the plurality of motor generator components and the plurality of peripheral members, and the second frequency in the audible frequency band is This is executed as the same frequency as any one of the plurality of motor generator constituent members and the plurality of peripheral members. Here, the second frequency is higher than the first frequency.

  In executing this frequency control, the first frequency and the second frequency are determined in advance, and the natural frequency of one motor generator component or peripheral member becomes the first frequency, and the other one motor generator component. Or you may design an electric vehicle drive device so that the natural frequency of a peripheral member may become a 2nd frequency. For example, the motor generator MG is designed so that the natural frequency of the stator winding is the first frequency and the natural frequency of the casing of the motor generator MG is the second frequency. Alternatively, the motor generator MG is designed so that the housing of the motor generator MG has the first frequency and the natural frequency of the transaxle has the second frequency.

  The control unit 18 obtains the vehicle speed A based on the rotation speed of the motor generator MG detected by the resolver 22 (S101). Then, it is determined whether the vehicle speed A is less than a predetermined first threshold Y1 (S102). When the vehicle speed A is less than the first threshold Y1, the control unit 18 selects the first frequency as the carrier frequency (S103). On the other hand, when the vehicle speed A is equal to or higher than the first threshold Y1, it is determined whether or not the vehicle speed A is less than a predetermined second threshold Y2 (S104). When the vehicle speed A is less than the second threshold Y2, the control unit 18 selects the second frequency as the frequency that should be the carrier frequency (S105). On the other hand, when the vehicle speed A is equal to or higher than the second threshold Y2, the third frequency higher than the frequency in the audible frequency band is selected as the frequency to be the carrier frequency (S106). The control unit 18 sets the carrier frequency to the selected frequency (S107), and controls the inverter 12 with the carrier frequency.

  FIG. 5 shows the relationship between the vehicle speed and the carrier frequency in the frequency control of the approach notification sound. The horizontal axis represents the vehicle speed, and the vertical axis represents the carrier frequency. That is, according to the frequency control of the approach notification sound, when the vehicle speed A is less than the first threshold Y1, the carrier frequency is set to the first frequency f1, and the member is notified of the approach with the natural frequency being the first frequency. A sound is emitted. When the vehicle speed A is equal to or higher than the first threshold Y1 and lower than the second threshold Y2, the carrier frequency is set to the second frequency f2, and an approach notification sound is emitted from a member whose natural frequency is the second frequency. Be emitted. Further, when the vehicle speed A is equal to or higher than the second threshold Y2, the carrier frequency is set to the third frequency f3. Since the third frequency is higher than the frequency within the audible frequency band, no audible sound is emitted in this case.

  According to such control, according to the vehicle speed A, two types of approach notification sounds having a frequency twice the first frequency and a frequency twice the second frequency are emitted. This can inform the pedestrian whether the vehicle is approaching at a fast speed or approaching at a slow speed.

  Here, the control for setting three ranges for the vehicle speed and setting the carrier frequency to any one of the first to third frequencies according to the range of the vehicle speed has been described. In addition to such control, the vehicle speed range may be subdivided into four or more, and control for setting the carrier frequency to any one of four or more different frequencies may be executed.

  Next, an application example of frequency control of approach notification sound will be described. As described above, when the approach notification sound is generated by the resonance phenomenon with respect to the ripple component of the current flowing through motor generator MG, the carrier frequency is set such that twice the frequency is within the audible frequency band. The carrier frequency set in this way is often lower than the carrier frequency in the conventional electric vehicle driving apparatus. In the motor generator controlled by the inverter, when the carrier frequency is lowered, problems such as an increase in energy loss and generation of vibration may occur, and the control characteristics during acceleration may be affected.

  Therefore, in the application control described below, when the operation amount of the accelerator pedal exceeds a predetermined threshold when the vehicle is traveling at a speed lower than a predetermined speed, the carrier frequency is set to the acceleration frequency. The acceleration frequency is a frequency within the audible frequency band and is higher than the second frequency. Further, the acceleration frequency coincides with the natural frequency of any one of the plurality of motor generator constituent members and the peripheral members. According to this application control, the carrier frequency can be set as high as possible within a range in which the approach notification sound can be generated, and the control characteristics during acceleration can be improved.

  FIG. 6 shows a flowchart of application control. The same processes as those shown in FIG. 4 are denoted by the same reference numerals and description thereof is omitted. The control unit 18 determines whether or not the accelerator pedal operation amount B is equal to or greater than a predetermined threshold T when the frequency to be the carrier frequency is selected in the process of step S103 or S105 (S201). When the operation amount B of the accelerator pedal is equal to or greater than the predetermined threshold T, the control unit 18 selects the acceleration frequency as the frequency to be set as the carrier frequency (S202). On the other hand, when the operation amount B of the accelerator pedal is less than the threshold value T, the frequency to be the carrier frequency is assumed to be selected by the process of step S103 or S105. The control unit 18 sets the carrier frequency to the selected frequency (S107), and controls the inverter 12 with the carrier frequency.

  According to such control, when the vehicle speed A is less than the speed threshold Y2 and the accelerator pedal operation amount B is greater than or equal to the threshold T, the carrier frequency is set to the acceleration frequency. In FIG. 7, an example of a change in carrier frequency is indicated by an arrow when the vehicle speed increases from 0 with time and the accelerator pedal operation amount B is equal to or greater than the threshold T when the vehicle speed is Ya. Has been. Before the vehicle speed reaches from 0 to Y1, the carrier frequency is set to the first frequency f1, and the carrier frequency is set to the second frequency f2 as the vehicle speed reaches Y1. When the vehicle speed reaches Ya, the accelerator pedal operation amount becomes equal to or greater than the threshold T, and the carrier frequency is set to the acceleration frequency fa.

  According to this application control, the carrier frequency is set to a frequency as high as possible within a range in which an approach notification sound can be generated. Thereby, the control characteristic at the time of acceleration can be improved. Further, according to the present application control, an approach notification sound having two kinds of pitches of a frequency twice the first frequency and a frequency twice the second frequency is emitted according to the vehicle speed A. Furthermore, when the operation amount B of the accelerator pedal is equal to or greater than the threshold value T, an approach notification sound having a pitch of twice the acceleration frequency is generated. Thereby, it is possible to inform the pedestrian whether the vehicle is approaching at a high speed or a low speed, and further whether the vehicle is accelerating.

  Here, the control for setting the frequency to be the carrier frequency based on the comparison determination (S201) between the operation amount of the accelerator pedal and the threshold value T is taken up. In addition to such control, control for setting the carrier frequency may be executed based on a comparison between a torque command value for motor generator MG and a predetermined threshold value. The torque command value is calculated by the control unit 18 based on the vehicle speed, the operation in the driving operation unit 20, and the like. The control unit 18 performs switching control of the inverter 12 based on the torque command value. That is, the driving operation unit 20 and the control unit 18 have a function as a vehicle acceleration control unit that performs acceleration control of the vehicle using the torque command value.

  In this case, when the torque command value is equal to or greater than a predetermined threshold, the control unit 18 selects the acceleration frequency as the frequency to be set as the carrier frequency. On the other hand, when the torque command value is less than the predetermined threshold, it is assumed that the frequency to be the carrier frequency has been selected by the process of step S103 or S105. Instead of the torque command value, other control variables (variables indicating the control state) used in the operation unit 20 and the control unit 18 to control the torque of the motor generator MG may be used.

  In addition, here, as the peripheral member that resonates at the frequency of the ripple component, components such as the torque transmission mechanism 14 and the motor generator MG are taken up. As the peripheral member, a resonance member intended to resonate at the frequency of the ripple component may be employed. As the resonance member, a plate-like member having a specific natural frequency, a cylindrical member, a box-like member, a tuning fork, or the like may be used. The resonance member is fixed to, for example, a portion of the motor generator MG where mechanical vibration occurs.

  The present invention may be used in the hybrid vehicle driving apparatus shown in FIG. The same components as those of the electric vehicle drive device shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted. Motor generator MG2 in this hybrid vehicle drive apparatus accelerates the vehicle and performs regenerative braking. Further, MG2 inverter 36 performs DC-AC conversion between DC power supply circuit 10 and motor generator MG2. MG2 inverter 36 and motor generator MG2 have the same configuration and function as inverter 12 and motor generator MG in the electric vehicle drive apparatus shown in FIG.

  That is, in the hybrid vehicle drive device, an approach notification sound is generated by resonating the constituent members or peripheral members of motor generator MG2 with mechanical vibrations based on the ripple component of the current flowing through motor generator MG2.

  The hybrid vehicle drive apparatus further starts the engine 40 and generates power by the driving force of the engine 40, and an inverter for MG1 that performs DC / AC conversion between the DC power supply circuit 10 and the motor generator MG1. 34 is provided.

  The shafts of engine 40 and motor generators MG1 and MG2 are attached to torque dividing mechanism 38. The torque dividing mechanism 38 applies torque between them. For the torque dividing mechanism 38, for example, a planetary gear unit including a sun gear, a ring gear, and a planetary gear is used. Further, a torque transmission mechanism 14 is attached to the shaft of motor generator MG2. For the torque transmission mechanism 14, for example, a differential gear that reduces the rotation speed of the wheel 16 with respect to the rotation speed of the shaft of the motor generator MG <b> 2 is used.

  Torque dividing mechanism 38 transmits torque generated by at least one of engine 40 and motor generator MG2 to torque transmitting mechanism 14 by adjusting the rotational states of engine 40, motor generator MG1 and motor generator MG2. Further, torque is transmitted between engine 40 and motor generator MG1.

  DC power supply circuit 10, MG2 inverter 36 and motor generator MG2 are based on the power supplied from the secondary battery by the same operations as those of DC power supply circuit 10, inverter 12 and motor generator MG shown in FIG. Torque is generated in motor generator MG2, the vehicle is accelerated with the torque, and the secondary battery is charged with generated power based on regenerative braking by motor generator MG2.

  In the hybrid vehicle drive device, the torque transmission mechanism 14, the torque dividing mechanism 38, the engine 40, the members constituting them, or the shaft that transmits torque between them are used as peripheral members that generate an approach notification sound. Can do.

  10 DC power supply circuit, 12 inverter, 14 torque transmission mechanism, 16 wheels, 18 control unit, 20 driving operation unit, 22 resolver, 24u, 24v, 24w IGBT set, 24-1 upper IGBT, 24-2 lower IGBT, 24 -3 diode, 26 triangular wave signal generator, 28 command signal generator, 30u, 30v, 30w subtractor, 32u, 32v, 32w driver, 34 MG1 inverter, 36 MG2 inverter, 38 torque division mechanism, 40 engine, MG , MG1, MG2 Motor generator.

Claims (9)

A motor for driving the vehicle;
An inverter for supplying power to the motor according to switching control;
A control unit that performs switching control on the inverter;
With
The motor generates an audible sound due to resonance when the frequency of the ripple component of the current flowing through the motor matches the natural frequency of the motor,
The controller is
A vehicle drive device that controls the frequency of the ripple component by adjusting a carrier frequency when performing switching control. In the vehicle drive device according to claim 1,
A vehicle driving device comprising a peripheral member that is used together with the motor and generates an audible sound due to resonance when the frequency of the ripple component and its own natural frequency coincide with each other. A motor for driving the vehicle;
An inverter for supplying power to the motor according to switching control;
A control unit that performs switching control on the inverter;
A peripheral member that is used together with the motor and generates an audible sound due to resonance when the frequency of the ripple component of the current flowing through the motor matches its own natural frequency;
With
The controller is
A vehicle drive device that controls the frequency of the ripple component by adjusting a carrier frequency when performing switching control. In the vehicle drive device according to claim 1 or 2,
The motor has a plurality of different natural frequencies;
The said control part adjusts a carrier frequency, and makes the frequency of the said ripple component correspond to either of these natural frequencies, The vehicle drive device characterized by the above-mentioned. In the vehicle drive device according to claim 2 or 3,
A plurality of the peripheral members having different natural frequencies;
The said control part adjusts a carrier frequency, and makes the frequency of the said ripple component correspond to either of the some natural frequency based on the said some peripheral member, The vehicle drive device characterized by the above-mentioned. The vehicle drive device according to claim 2,
A plurality of the peripheral members having different natural frequencies;
The motor has a plurality of different natural frequencies;
The said control part adjusts a carrier frequency, and makes the frequency of the said ripple component correspond to either among the some natural frequency based on the said motor and several said peripheral members, The vehicle drive device characterized by the above-mentioned. In the vehicle drive device according to any one of claims 4 to 6,
The control unit selects one of a plurality of frequencies determined corresponding to the plurality of natural frequencies according to the speed of the vehicle, and sets a carrier frequency to the selected frequency. A vehicle drive device. In the vehicle drive device according to any one of claims 4 to 6,
The control unit selects one of a plurality of frequencies determined corresponding to the plurality of natural frequencies according to a state of an acceleration control unit that controls the acceleration of the vehicle, and the carrier is set to the selected frequency. A vehicle drive device characterized by setting a frequency. The vehicle drive device according to claim 8, wherein
The acceleration control unit includes an accelerator pedal,
A vehicle drive device, wherein a frequency higher than the previously selected frequency is selected according to a comparison between an operation amount of the accelerator pedal and a predetermined threshold value.

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