JP2020137217A - Driving device - Google Patents

Abstract

To suppress a situation where a torque of a motor significantly changes when a control mode of an inverter is switched from a pulse width modulation control mode to a rectangular wave control mode.SOLUTION: When preparation for switching from a pulse width modulation control mode to a rectangular wave control mode is required and a voltage phase in the pulse width modulation control mode is larger than a voltage phase upper limit in the rectangular wave control mode, until the voltage phase in the pulse width modulation control mode reaches at least the voltage phase upper limit in the rectangular wave control mode or smaller, a current advance angle command is set so that a current advance angle in the rectangular wave control mode based on a torque command, an angular speed of a motor, and an input voltage of an inverter is gradually approached, and the inverter is controlled on the basis of the current advance angle command and the torque command.SELECTED DRAWING: Figure 2

Description

The present invention relates to a drive device.

Conventionally, as a drive device of this type, when controlling an inverter that drives a motor by switching a plurality of switching elements in a PWM control mode, the optimum current that maximizes the output torque for each current amplitude is normally used. The torque command of the motor is applied to the optimum efficiency characteristic line connecting the phases to set the current command (current phase and current amplitude) to control the inverter, and when the generated power of the motor becomes excessive, the current phase is set to the optimum value. A method has been proposed in which a current command is set by applying a torque command of a motor to a loss increase characteristic line advanced to control an inverter (see, for example, Patent Document 1).

JP-A-2007-151336

In the above-mentioned drive device, when switching from the inverter control in the PWM control mode using the loss increase characteristic line to the inverter control in the square wave control mode, the voltage phase and the voltage phase suddenly change and the torque of the motor becomes large. May fluctuate.

The main purpose of the drive device of the present invention is to suppress large fluctuations in the torque of the motor when the control mode of the inverter is switched from the pulse width modulation control mode to the square wave control mode.

The drive device of the present invention has adopted the following means in order to achieve the above-mentioned main object.

The drive device of the present invention
With the motor
An inverter that drives the motor by switching a plurality of switching elements,
A power storage device connected to the inverter via a power line,
A control device that controls the inverter by switching between a pulse width modulation control mode and a square wave control mode based on a torque command of the motor.
It is a drive device equipped with
The control device is
When it is necessary to prepare for switching from the pulse width modulation control mode to the square wave control mode and the voltage phase in the pulse width modulation control mode is larger than the voltage phase upper limit in the square wave control mode.
Until the voltage phase in the pulse width modulation control mode is at least below the upper limit of the voltage phase in the square wave control mode.
The current advance command is set so as to gradually approach the current advance in the square wave control mode based on the torque command, the angular velocity of the motor, and the input voltage of the inverter.
The inverter is controlled based on the current advance command and the torque command.
The gist is that.

In the drive device of the present invention, when it is necessary to prepare for switching from the pulse width modulation control mode to the rectangular wave control mode and the voltage phase in the pulse width modulation control mode is larger than the voltage phase upper limit in the rectangular wave control mode, Until the voltage phase in the pulse width modulation control mode is at least below the upper limit of the voltage phase in the rectangular wave control mode, the current advance angle in the rectangular wave control mode based on the torque command, the angular speed of the motor, and the input voltage of the inverter is directed. The current advance command is set so as to gradually approach the inverter, and the inverter is controlled based on the current advance command and the torque command. With such control, it is possible to suppress the torque of the motor from deviating from the torque command when preparation for switching is required, and the voltage phase fluctuates greatly when switching from the pulse width modulation control mode to the square wave control mode. It is possible to suppress the torque of the motor from fluctuating significantly.

Here, "when it is necessary to prepare for switching from the pulse width modulation control mode to the rectangular wave control mode" may be when the modulation factor is larger than the threshold value. In addition, when "when the voltage phase in the pulse width modulation control mode is larger than the voltage phase upper limit in the square wave control mode", the field weakening control (the current advance command used for motor control is on the advance side of the optimum advance). It may be the case that the control for increasing the loss of the motor is being performed. The field weakening control is performed, for example, when the allowable input power of the power storage device is equal to or less than the threshold value.

In such a drive device of the present invention, when the control device sets the current advance angle in the square wave control mode, the control device is based on the torque command, the angular speed of the motor, and the input voltage of the inverter. The d-axis and q-axis currents in the wave control mode may be estimated, and the current advance angle in the square wave control mode may be set based on the d-axis and q-axis currents in the square wave control mode. .. In this way, the current advance angle at the time of a square wave can be set more appropriately.

In this case, when the control device estimates the d-axis and q-axis currents in the square wave control mode, the square wave is based on the torque command, the angular speed of the motor, and the input voltage of the inverter. The voltage phase in the control mode is estimated, and the d-axis and q-axis voltages in the square wave control mode are estimated based on the voltage phase in the square wave control mode and the input voltage of the inverter, and the square wave is estimated. The d-axis and q-axis currents in the square wave control mode may be estimated based on the d-axis and q-axis voltages in the control mode and the angular velocity of the motor. In this way, the d-axis and q-axis square wave currents can be estimated more appropriately.

It is a block diagram which shows the outline of the structure of the electric vehicle 20 which mounts the drive device as one Example of this invention. It is a flowchart which shows an example of the setting routine such as a current advance command executed by an electronic control unit 50. It is explanatory drawing which shows an example of the map which defined the relationship between the torque Tm of a motor 32, the optimum advance angle line, the loss increase line, the current advance angle φi, and the current effective value Ir. It is explanatory drawing for demonstrating the state of movement of a voltage phase φv and a current advance angle φi when it is necessary to prepare for switching from a PWM control mode to a rectangular wave control mode.

Next, a mode for carrying out the present invention will be described with reference to Examples.

FIG. 1 is a configuration diagram showing an outline of a configuration of an electric vehicle 20 equipped with a drive device as an embodiment of the present invention. As shown in the figure, the electric vehicle 20 of the embodiment includes a motor 32, an inverter 34, a battery 36 as a power storage device, and an electronic control unit 50. The "driving device" of the embodiment mainly corresponds to the motor 32, the inverter 34, and the electronic control unit 50.

The motor 32 is configured as a synchronous motor generator, and includes a rotor in which a permanent magnet is embedded in a rotor core and a stator in which a three-phase coil is wound around a stator core. The rotor of the motor 32 is connected to a drive shaft 26 connected to the drive wheels 22a and 22b via a differential gear 24.

The inverter 34 is used to drive the motor 32. The inverter 34 is connected to the battery 36 via a power line 38, and six diodes D11 to six transistors T11 to T16 as six switching elements and six diodes D11 to each of the six transistors T11 to T16 are connected in parallel. It has D16. Two transistors T11 to T16 are arranged in pairs so as to be on the source side and the sink side with respect to the positive electrode bus and the negative electrode bus of the power line 38, respectively. Further, each of the three-phase coils (U-phase, V-phase, and W-phase coils) of the motor 32 is connected to each of the connection points between the transistors paired with the transistors T11 to T16. Therefore, when a voltage is applied to the inverter 34, the electronic control unit 50 adjusts the on-time ratio of the transistors T11 to T16 paired with the inverter 34, so that the rotating magnetic field is applied to the three-phase coil of the motor 32. Is formed, and the rotor of the motor 32 is rotationally driven.

The battery 36 is configured as, for example, a lithium ion secondary battery or a nickel hydrogen secondary battery, and is connected to the inverter 34 via the power line 38 as described above. A smoothing capacitor 39 is attached to the positive electrode bus and the negative electrode bus of the power line 38.

The electronic control unit 50 is configured as a microprocessor centered on a CPU 51, and includes a ROM 52 for storing a processing program, a RAM 53 for temporarily storing data, and an input / output port in addition to the CPU 51. Signals from various sensors are input to the electronic control unit 50 via input ports. The signals input to the electronic control unit 50 include, for example, the rotation position θm of the rotor of the motor 32 from the rotation position detection sensor (for example, resolver) 32a that detects the rotation position of the rotor of the motor 32, and the rotation position θm of the motor 32. Examples of the U-phase and V-phase currents Iu and Iv of the motor 32 from the current sensors 32u and 32v attached to the U-phase and V-phase can be mentioned. Further, the voltage Vb of the battery 36 from the voltage sensor 36a attached between the terminals of the battery 36, the current Ib of the battery 36 from the current sensor 36b attached to the output terminal of the battery 36, and the temperature attached to the battery 36. The temperature Tb of the battery 36 from the sensor 36c and the voltage VH of the smoothing capacitor 39 (power line 38) from the voltage sensor 39a attached between the terminals of the smoothing capacitor 39 can also be mentioned. Further, the ignition signal from the ignition switch 60, the shift position SP from the shift position sensor 62 that detects the operation position of the shift lever 61, and the accelerator opening Acc from the accelerator pedal position sensor 64 that detects the amount of depression of the accelerator pedal 63. , The brake pedal position BP from the brake pedal position sensor 66 that detects the depression amount of the brake pedal 65, and the vehicle speed V from the vehicle speed sensor 68 can also be mentioned.

From the electronic control unit 50, switching control signals and the like to the transistors T11 to T16 of the inverter 34 are output via the output port. The electronic control unit 50 calculates the electric angle θe, the electric angular velocity ωe, and the rotation speed Nm of the motor 32 based on the rotation position θm of the rotor of the motor 32 from the rotation position detection sensor 32a. Further, the electronic control unit 50 calculates the storage ratio SOC of the battery 36 based on the integrated value of the current Ib of the battery 36 from the current sensor 36b, and the calculated storage ratio SOC and the temperature of the battery 36 from the temperature sensor 36c. The input / output restrictions Win and Wout of the battery 36 are set based on Tb. Here, the storage ratio SOC is the ratio of the capacity of the power that can be discharged from the battery 36 to the total capacity of the battery 36, and the input / output restrictions Win and Wout are the allowable input / output powers that may charge and discharge the battery 36. is there.

In the electric vehicle 20 of the embodiment configured in this way, the electronic control unit 50 sets the required torque Td * required for the drive shaft 26 based on the accelerator opening degree Acc and the vehicle speed V, and sets the required torque Td *. The torque command Tm * of the motor 32 is set so that is output to the drive shaft 26, and the switching control of the transistors T11 to T16 of the inverter 34 is performed so that the motor 32 is driven by the torque command Tm *.

Here, the control of the inverter 34 will be described. In the embodiment, the electronic control unit 50 controls the inverter 34 by switching between the pulse width modulation (PWM) control mode and the rectangular wave control mode. The PWM control mode is a control mode for controlling the inverter 34 so that a pseudo three-phase AC voltage or an overmodulation voltage is applied to the motor 32, and the square wave control mode is a control mode in which a square wave voltage is applied to the motor 32. This is a control mode for controlling the inverter 34 so as to control the inverter 34. In the PWM control mode, the modulation factor Vr is a value of 0 to less than 0.78, and in the square wave control mode, the modulation factor Vr is 0.78.

When controlling the inverter 34 in the PWM control mode, the electronic control unit 50 first assumes that the total current of each phase of the motor 32 is 0, and uses the electric angle θe of the motor 32 to perform the U phase and Coordinate conversion (3-phase-2 phase conversion) is performed on the V-phase phase currents Iu and Iv to the d-axis and q-axis currents Id and Iq. Subsequently, according to the current advance command and the like setting routine described later, the current advance command φi *, which is an advance command for the q-axis of the current supplied to the motor 32, and the current effective value, which is the effective value of the current supplied to the motor 32, are used. Set Ir. Then, the d-axis and q-axis current commands Id * and Iq * are set based on the set current advance command φi * and the current effective value Ir. This process is obtained as the current effective value Ir obtained by dividing the square root of the sum of the square of the current command Id * on the d-axis and the square of the current command Iq * on the q-axis by √3, and the current advance value. It is performed in consideration of the fact that θi is obtained as an angle (advance value) with respect to the q-axis of the current vector having the current commands Id * and Iq * of the d-axis and the q-axis in the dq coordinate system as components.

Subsequently, the voltage commands Vd * and Vq * on the d-axis and q-axis are calculated so that the difference between the current commands Id * and Iq * on the d-axis and q-axis and the currents Id and Iq is canceled. When the d-axis and q-axis voltage commands Vd * and Vq * are set in this way, the d-axis and q-axis voltage commands Vd * and Vq * are set to the voltage commands Vu * and Vv of each phase using the electric angle θe of the motor 32. Coordinate conversion to *, Vw * (2-phase-3 phase conversion) is performed, and PWM signals of transistors T11 to T16 are generated by comparing the voltage commands Vu *, Vv *, Vw with the carrier voltage, and the transistors T11 to T16 Perform switching control. Further, the modulation factor Vr and the voltage phase φv are calculated based on the voltage commands Vd * and Vq * on the d-axis and the q-axis. The modulation factor Vr is obtained by dividing the square root of the sum of the square of the voltage command Vd * on the d-axis and the square of the voltage command Vq * on the q-axis by the voltage VH of the power line 38, and the voltage phase φv is the d-axis. And, it is obtained as an angle (advance value) of a voltage vector having voltage commands Vd * and Vq * on the q-axis with respect to the q-axis.

When controlling the inverter 34 in the square wave control mode, the electronic control unit 50 first calculates the d-axis and q-axis currents Id and Iq in the same manner as when controlling the inverter 34 in the PWM control mode. The estimated torque Tmes of the motor 32 is obtained based on the calculated d-axis and q-axis currents Id and Iq. Subsequently, the voltage phase target φvtag is set so that the difference between the torque command Tm * of the motor 32 and the estimated torque Tmes is canceled, the voltage phase target φvtag is limited by the voltage phase upper limit φvmax (upper limit guard), and the voltage phase command is given. Set φv *. When the voltage phase command φv * is set in this way, the rectangular wave signals of the transistors T11 to T16 are generated based on the set voltage phase command φv * and the electric angle θe, and the switching control of the transistors T11 to T16 is performed.

Next, the operation of the electric vehicle 20 of the embodiment configured in this way, particularly the setting process of the current advance command φi * and the current effective value Ir when controlling the inverter 34 in the PWM control mode will be described. FIG. 2 is a flowchart showing an example of a current advance command and the like setting routine executed by the electronic control unit 50. This routine is repeatedly executed when the inverter 34 is controlled in the PWM control mode.

When the current advance command setting routine of FIG. 2 is executed, the electronic control unit 50 first receives the input limit Win of the battery 36, the modulation factor Vr, the voltage phase φv, the torque command Tm * of the motor 32, and electricity. Data such as the angular velocity ωe and the voltage VH of the power line 38 are input (step S100). Here, the input limit Win of the battery 36 is a value calculated based on the storage ratio SOC based on the integrated value of the current Ib of the battery 36 and the temperature Tb of the battery 36. For the modulation factor Vr, the voltage phase φv, and the torque command Tm * of the motor 32, the values set by the above processing are input. For the electric angular velocity ωe of the motor 32, a value calculated based on the rotation position θm of the motor 32 is input. For the voltage VH of the power line 38, the value detected by the voltage sensor 39a is input.

When the data is input in this way, the absolute value of the input limit Win of the input battery 36 is compared with the threshold value Winref (step S110). Here, the threshold value Winref determines whether or not execution of field weakening control that increases the loss of the motor 32 by setting the current advance command φi * of the motor 32 to the advance side of the optimum advance angle is required. It is a threshold value used, for example, a value of 0 or a value slightly larger than that is used. Here, the "optimal advance angle" refers to the amount of advance angle at which the effective current value Ir is minimized when the motor 32 is driven by the torque command Tm *.

When the absolute value of the input limit Win of the battery 36 is larger than the threshold value Winref, it is determined that the execution of the field weakening control is not required, and the optimum advance angle is set to the current advance angle target φitag (step S120). FIG. 3 is an explanatory diagram showing an example of a map that defines the relationship between the torque Tm of the motor 32, the optimum advance angle line, the loss increase line, the current advance angle φi, and the current effective value Ir. Here, the "optimal advance angle line" and the "loss increase line" are lines connecting the optimum advance angle and the current advance angle for field weakening control for each value of the torque of the motor 32, respectively. This map is determined by experimentation and analysis. In the process of setting the current advance target φitag in step S120, the torque command Tm * of the motor 32 is applied to the map of FIG. 3, the optimum advance line is selected, and the torque command Tm * of the motor 32 and the optimum advance line are combined. This is performed by setting the current advance angle φi at the intersection of the above as the current advance target φitag.

When the current advance target φitag is set in this way, the set current advance target φitag is subjected to rate processing to set the current advance command φi * (step S250), and the set current advance command φi * and the torque of the motor 32 are set. The command Tm * is applied to the map of FIG. 3, the current effective value Ir is set (step S260), and this routine is terminated. When the current advance command φi * and the current effective value Ir are set in this way, the inverter 34 is controlled based on the current advance command φi * and the current effective value Ir as described above.

When the absolute value of the input limit Win of the battery 36 is equal to or less than the threshold value Winref in step S110, it is determined that the execution of field weakening control is required, the modulation factor Vr is compared with the threshold value Vrref (step S130), and the modulation factor Vr is When it is equal to or less than the threshold value Vrref, the modulation factor Vr is compared with a value (Vrref-α) smaller than the threshold value Vrref by a predetermined value α (step S140). Here, the threshold value Vrref is a threshold value used for determining whether or not the control mode of the inverter 34 may be switched from the PWM control mode to the rectangular wave control mode and preparation for the switching is required, for example. , 0.72 to 0.75 is used.

When the modulation factor Vr is larger than the threshold value Vrref, it is determined that switching preparation is necessary, and a value 1 is set in the switching preparation flag Fs (step S150). When the modulation factor Vr is less than the value (Vrref-α), it is determined that the switching preparation is not necessary, and the switching preparation flag Fs is set to the value 0 (step S160). When the modulation factor Vr is equal to or less than the threshold value Vrref and equal to or greater than the value (Vrref−α), the value of the previous switching preparation flag (previous Fs) is held (step S170). The predetermined value α is a value used to suppress frequent switching of the switching preparation flag Fs, and for example, about 0.02 to 0.05 is used.

When the switching preparation flag Fs is set in this way, the value of the set switching preparation flag Fs is checked (step S180). When the switching preparation flag Fs has a value of 0, it is determined that switching preparation is not necessary, the field weakening advance angle is set to the current advance angle target φitag (step S210), and the current advance angle is processed by the above steps S250 and S260. Set the command φi * and the current effective value Ir, and end this routine. Here, in the process of setting the current advance target φitag in step S210, the torque command Tm * of the motor 32 is applied to the map of FIG. 3 and the loss increase line is selected, and the torque command Tm * of the motor 32 and the loss increase line are selected. This is performed by setting the current advance angle φi at the intersection with and as the current advance target φitag.

When the switching preparation flag Fs is a value 1 in step S180, it is determined that switching preparation is necessary, the voltage phase φv is compared with the voltage phase upper limit φvmax in the square wave control mode (step S190), and the voltage phase φv is rectangular. When the voltage phase upper limit φvmax or less in the wave control mode is equal to or lower, the voltage phase φv is compared with a value (φvmax−β) smaller than the voltage phase upper limit φvmax in the square wave control mode by a predetermined value β (step S200).

When the voltage phase φv is larger than the voltage phase upper limit φvmax in the rectangular wave control mode, the inverter 34 is operated in the rectangular wave control mode based on the torque command Tm * of the motor 32, the electric angular velocity ωe, and the voltage VH of the power line 38. Control voltage phase (hereinafter referred to as "rectangular wave voltage phase φvs"), d-axis and q-axis voltage (hereinafter referred to as "rectangular wave voltage Vds, Vqs"), d-axis and q-axis current (hereinafter referred to as "rectangular wave voltage Vds, Vqs") Hereinafter, “rectangular wave currents Ids, Iqs”) are estimated in order (step S220).

Here, the square wave voltage phase φvs is the equation (1) defined as the relationship between the torque command Tm * of the motor 32, the electric angular velocity ωe of the motor 32, the voltage VH of the power line 38, and the square wave voltage phase φvs. Can be estimated using. The d-axis and q-axis square wave voltages Vds and Vqs can be estimated based on the square wave voltage phase φvs and the voltage VH of the power line 38. The d-axis and q-axis square wave currents Ids and Iqs are the d-axis and q-axis square wave voltages Vds and Vqs and the d-axis and q-axis square wave currents Ids and Iqs and the electric angular velocity ωe of the motor 32. It can be estimated using the equations (2) and (3) that define the relationship between. Here, in equations (1) to (3), "P" is the number of pole pairs of the motor 32, "φa" is the counter electromotive voltage constant, and "0.78" is the square wave control mode. The modulation factor Vr, where "Ld" and "Lq" are the inductances of the d-axis and the q-axis, respectively.

When the d-axis and q-axis square wave currents Ids and Iqs are estimated in this way, the current advance target φitag is set based on the estimated d-axis and q-axis square wave currents Ids and Iqs (step S230). The current advance command φi * and the current effective value Ir are set by the processing of steps S250 and S260 of the above, and this routine is terminated. The current advance target φitag in this case can be obtained as an angle (advance value) with respect to the q-axis of the current vector having the square wave currents Ids and Iqs of the d-axis and the q-axis in the dq coordinate system as components. ..

Therefore, when the processes of steps S220, S230, and S250 are repeatedly executed, the current advance command φi * is weakened and the current advance angles corresponding to the square wave currents Ids and Iqs of the d-axis and the q-axis from the field advance angle (hereinafter referred to as “)”. , "Language current advance angle φis"), and along with this, the voltage phase φv is gradually brought closer toward the square wave voltage phase φvs.

When the voltage phase φv is less than the value (φvmax-β) in step S200, the weakening field advance angle is set to the current advance target φitag (step S210), and the current advance command φi is processed by the above steps S250 and S260. * And the current effective value Ir are set, and this routine ends.

Therefore, when the processes of steps S210 and S250 are repeatedly executed, the current advance command φi * is weakened while the torque of the torque command Tm * is output from the motor 32, and the current advance command φi * is gradually approached toward the field advance angle. Therefore, the voltage phase φv is gradually brought closer to the voltage phase corresponding to the currents Id and Iq of the d-axis and q-axis of the loss increase line (hereinafter, referred to as “weakened field voltage phase φvw”).

When the voltage phase φv is equal to or less than the voltage phase upper limit φvmax and greater than or equal to the value (φvmax-β) in the rectangular wave control mode in steps S190 and S200, the current advance target φitag is set by the previous setting method (step S240). The current advance command φi * and the current effective value Ir are set by the processing of steps S250 and S260 described above, and this routine is terminated.

Therefore, from the state where the voltage phase φv is larger than the voltage phase upper limit φvmax in the square wave control mode, the current advance command φi * is gradually brought closer toward the square wave current advance φis, and the voltage phase φv is set to the square wave voltage. When gradually approaching the phase φvs, this will continue until the voltage phase φv reaches the value (φvmax−β). Further, from the state where the voltage phase φv is less than the value (φvmax−β), the current advance command φi * is weakened and gradually approaches the field advance angle, and the voltage phase φv is weakened and gradually approaches the field voltage phase φvw. When approaching, this will continue until the voltage phase φv reaches the voltage phase upper limit φvmax in the rectangular wave control mode.

In this way, the current advance command φi * can be set so that the voltage phase φv is within the range of the value (φvmax−β) from the voltage phase upper limit φvmax in the rectangular wave control mode. Then, the current advance command φi * and the torque command Tm * of the motor 32 are applied to the map of FIG. 3 to set the current effective value Ir, and based on the set current advance command φi * and the current effective value Ir. By controlling the inverter 34 by setting the d-axis and q-axis current commands Id * and Iq *, the torque of the torque command Tm * can be output from the motor 32. That is, it is possible to prevent the torque of the motor 32 from deviating from the torque command Tm *.

Further, the control mode of the inverter 34 is PWM-controlled by setting the current advance command φi * so that the voltage phase φv is within the range of the value (φvmax−β) from the voltage phase upper limit φvmax in the square wave control mode. When the mode is switched to the square wave control mode, it is possible to suppress a large fluctuation in the voltage phase φv and a large fluctuation in the torque of the motor 32.

FIG. 4 is an explanatory diagram for explaining how the voltage phase φv and the current advance angle φi move when it is necessary to prepare for switching from the PWM control mode to the rectangular wave control mode. FIG. 4A is a map defining the relationship between the torque of the motor 32 and the voltage phase φv, and FIG. 4B is a map similar to that of FIG. In FIG. 4B, the line where “φv = φvs” is a line connecting the current advance angles φi which are “φv = φvs” for each value of the torque of the motor 32, and the voltage VH of the power line 38. It depends on the electric angular velocity ωe of the motor 32 and the motor 32. Further, points A and A', points B and B', and points C and C'correspond to each other. As shown in the figure, it is necessary to prepare for switching from the PWM control mode to the square wave control mode, and the voltage phase φv is larger than the voltage phase upper limit φvmax in the square wave control mode (current advance angle φi corresponds to the voltage phase upper limit φvmax). When the current phase φi is larger than the current phase φi (see point A, point A'), the square wave current advance angle φis (see point B') until the voltage phase φv is at least below the voltage phase upper limit φvmax (see point C'). The current advance angle φi is gradually brought closer toward (see). Then, the current effective value Ir is set so that the torque command Tm * of the motor 32 is held. By such control, it is possible to suppress the torque of the motor 32 from deviating from the torque command Tm * when preparation for switching is required, and when the PWM control mode is switched to the square wave control mode, the voltage phase φv is changed. It is possible to suppress large fluctuations and suppress large fluctuations in the torque of the motor 32.

In the drive device mounted on the electric vehicle 20 of the embodiment described above, it is necessary to prepare for switching from the PWM control mode to the rectangular wave control mode, and the voltage phase φv is larger than the voltage phase upper limit φvmax in the rectangular wave control mode. Occasionally, until the voltage phase φv reaches the value (φvmax-β), the current advance angle φis at the time of rectangular wave is set to the current advance target φitag, and the current advance target φitag is rate-processed to perform the current advance command φi *. Is set, the current effective value Ir is set based on the current advance command φi * and the torque command Tm *, and the inverter 34 is controlled based on the current advance command φi * and the current effective value Ir. By such control, it is possible to suppress the torque of the motor 32 from deviating from the torque command Tm * when preparation for switching is required, and when the PWM control mode is switched to the square wave control mode, the voltage phase φv is changed. It is possible to suppress large fluctuations and suppress large fluctuations in the torque of the motor 32.

In the drive device mounted on the electric vehicle 20 of the embodiment, when estimating the d-axis and q-axis rectangular wave currents Ids and Iqs, the torque command Tm * of the motor 32, the electric angular velocity ωe, and the power line 38 The rectangular wave voltage phase φvs is estimated based on the voltage VH, and the d-axis and q-axis rectangular wave voltages Vds and Vqs are estimated based on the rectangular wave voltage phase φvs and the voltage VH of the power line 38. The d-axis and q-axis rectangular wave currents Ids and Iqs are estimated based on the d-axis and q-axis rectangular wave voltages Vds and Vqs and the electric angular velocity ωe of the motor 32. However, using a map or the like that defines the relationship between the torque command Tm * of the motor 32, the electric angular velocity ωe, the voltage VH of the power line 38, and the square wave currents Ids and Iqs of the d-axis and q-axis, the square wave voltage. The d-axis and q-axis square wave currents Ids and Iqs may be estimated without estimating the phase φvs and the d-axis and q-axis square wave voltages Vds and Vqs.

In the drive device mounted on the electric vehicle 20 of the embodiment, the battery 36 is used as the power storage device, but a capacitor may be used.

In the embodiment, the drive device is mounted on the electric vehicle 20 including the motor 32 and the inverter 34. However, it may be in the form of a drive device mounted on a hybrid vehicle including an engine in addition to the motor 32 and the inverter 34, or as a drive device mounted on a moving body such as a vehicle, a ship, or an aircraft other than the automobile. Alternatively, it may be in the form of a drive device mounted on non-moving equipment such as construction equipment.

The correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the motor 32 corresponds to the "motor", the inverter 34 corresponds to the "inverter", and the electronic control unit 50 corresponds to the "control device".

As for the correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem, the invention described in the column of means for solving the problem in the examples is carried out. Since it is an example for specifically explaining the form for solving the problem, the elements of the invention described in the column of means for solving the problem are not limited. That is, the interpretation of the invention described in the column of means for solving the problem should be performed based on the description in the column, and the examples are the inventions described in the column of means for solving the problem. It is just a concrete example.

Although the embodiments for carrying out the present invention have been described above with reference to Examples, the present invention is not limited to these Examples, and various embodiments are used without departing from the gist of the present invention. Of course, it can be done.

The present invention can be used in the driving device manufacturing industry and the like.

20 electric vehicle, 22a, 22b drive wheel, 24 differential gear, 26 drive shaft, 32 motor, 32a rotation position detection sensor, 32u, 32v current sensor, 34 inverter, 36 battery, 36a voltage sensor, 36b current sensor, 36c temperature sensor , 38 power line, 39 smoothing capacitor, 39a voltage sensor, 50 electronic control unit, 51 CPU, 52 ROM, 53 RAM, 60 ignition switch, 61 shift lever, 62 shift position sensor, 63 accelerator pedal, 64 accelerator pedal position sensor, 65 brake pedal, 66 brake pedal position sensor, 68 vehicle speed sensor, D11 to D16 diodes, T11 to T16 transistors.

Claims (1)

With the motor
An inverter that drives the motor by switching a plurality of switching elements,
A power storage device connected to the inverter via a power line,
A control device that controls the inverter by switching between a pulse width modulation control mode and a square wave control mode based on a torque command of the motor.
It is a drive device equipped with
The control device is
When it is necessary to prepare for switching from the pulse width modulation control mode to the square wave control mode and the voltage phase in the pulse width modulation control mode is larger than the voltage phase upper limit in the square wave control mode.
Until the voltage phase in the pulse width modulation control mode is at least below the upper limit of the voltage phase in the square wave control mode.
The current advance command is set so as to gradually approach the current advance in the square wave control mode based on the torque command, the angular velocity of the motor, and the input voltage of the inverter.
The inverter is controlled based on the current advance command and the torque command.
Drive device.

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