JP5366634B2 - Electric motor control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller of a motor, capable of operating the motor at high operation efficiency without being influenced by overshoot generated in voltage conversion. <P>SOLUTION: The controller of a motor includes: a rectangular wave inverter for supplying a rectangular wave voltage to a stator of a motor to drive the motor; a voltage conversion section for stepping up or down the output voltage of a DC power supply and applying the stepped up or down voltage to the rectangular wave inverter; an output voltage command generating section for generating an output voltage command for indicating the output voltage of the voltage conversion section; a conduction mode switching section for switching the mode of conduction by the rectangular wave inverter during rectangular wave control; and an electric angle acquiring section for acquiring an electric angle of the rotor of the motor. When a change amount of a target DC voltage of the voltage conversion section satisfies a predetermined condition, the conduction mode switching section switches the conduction mode to two-phase conduction with dead time, and the output voltage command generating section generates an output voltage command for gradually stepping up or down toward the target DC voltage synchronously with the change in the electric angle of the rotor acquired by the electric angle acquiring section. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a control device for an electric motor having a rotor and a stator that rotates a rotor by generating a rotating magnetic field by an applied voltage.

  FIG. 8 is a block diagram showing the load driving device disclosed in Patent Document 1. As shown in FIG. 8 includes a DC power source B, system relays SR1 and SR2, voltage sensors 10 and 16, a boost converter 11, a capacitor 12, an inverter 20, a current sensor 24, and a control device 30. With. In the load driving device 100, when the boost converter 11 boosts the DC voltage from the DC power source B and supplies it to the inverter 20, if the motor generator MG as a load is driven in the rectangular wave control mode, the DC power source B Current take-out increases and overcurrent occurs. Therefore, when control operation of boost converter 11 is commanded when control mode of motor generator MG is the rectangular wave control mode, control device 30 of load drive device 100 sets the control mode to an overmodulation control mode or a PWM control mode. Inverter 20 is controlled to drive motor generator MG.

  Note that the rectangular wave control mode is a control mode for controlling the current flowing through the motor generator MG in synchronization with the rising and falling of one pulse. For this reason, if the current flowing to motor generator MG is controlled at the rising edge of one pulse, the current flowing to motor generator MG cannot be controlled until the next falling timing. As a result, the carry-out of current from the DC power supply B increases and an overcurrent is generated. However, since the timing for controlling the current flowing through motor generator MG is small, the switching loss that occurs when switching the switching elements constituting boost converter 11 and inverter 20 is small. For this reason, the operating efficiency of motor generator MG can be increased.

  On the other hand, the overmodulation control mode and the PWM control mode have more timings for controlling the current flowing through the motor generator MG than in the rectangular wave control mode. Therefore, the amount of current flowing through motor generator MG can be controlled with high accuracy in accordance with the voltage level supplied from boost converter 11. As a result, the amount of current taken from the DC power supply B is reduced, so that overcurrent can be suppressed. However, since there are many timings for controlling the current flowing through the motor generator MG, the switching loss is large.

JP 2005-51894 A

  However, when the boost converter 11 performs a boost operation, an overshoot occurs in the output voltage. In particular, the overshoot when the boost converter 11 performs a steep boost operation is large. The overshoot generated in the output voltage of boost converter 11 eventually causes an overshoot of the torque output from motor generator MG. Further, when the boost converter 11 that has been in the rectangular wave control mode is switched to the overmodulation control mode and the PWM control mode during the boost operation, the high operating efficiency of the motor generator MG obtained in the rectangular wave control mode cannot be obtained.

  An object of the present invention is to provide a control device for an electric motor in which the electric motor can operate with high operating efficiency without being affected by overshoot that occurs during voltage conversion.

In order to solve the above-described problems and achieve the object, an electric motor control device according to claim 1 includes a rotor, a stator that generates a rotating magnetic field by an applied voltage, and rotates the rotor. A rectangular wave inverter that drives the motor by applying a rectangular wave voltage to the stator of the motor (for example, the embodiment). Inverter 117) and a voltage converter (for example, DCDC converter 123 in the embodiment) that boosts or steps down the output voltage of the DC power source (for example, the battery 15 in the embodiment) and applies it to the rectangular wave inverter. ), An output voltage command generation unit (for example, output voltage command generation unit 121 in the embodiment) that generates an output voltage command for instructing an output voltage of the voltage conversion unit, and a rectangular wave control (E.g., 1PLS control in the embodiment), the energization mode switching unit (e.g., the energization mode switching determination unit 131 in the embodiment) that switches the energization mode performed by the rectangular wave inverter, and the rotor of the motor An electrical angle acquisition unit (for example, the resolver 101 in the embodiment) that acquires an electrical angle, and when the amount of change in the target DC voltage of the voltage conversion unit satisfies a predetermined condition, The energization mode is switched to two-phase energization with dead time, and the output voltage command generator is directed to the target DC voltage in synchronization with a change in the electrical angle of the rotor acquired by the electrical angle acquisition unit. It generates the output voltage command for instructing to stepwise raised or lowered Te, the voltage conversion unit in response to the output voltage command, an output voltage of the DC power supply temperature during the dead Or it is characterized by the step-down.

Furthermore, in the motor control device according to the second aspect of the present invention, an electric motor (for example, in the embodiment) having a rotor and a stator that generates a rotating magnetic field by an applied voltage and rotates the rotor. A control device for the electric motor 10), a rectangular wave inverter that drives the electric motor by applying a rectangular wave voltage to the stator of the electric motor (for example, the inverter 117 in the embodiment), and a DC power source (for example, A voltage converter (for example, DCDC converter 123 in the embodiment) that boosts or lowers the output voltage of the battery 15) in the embodiment and applies it to the rectangular wave inverter, and indicates the output voltage of the voltage converter Output voltage command generation unit (for example, output voltage command generation unit 121 in the embodiment) for generating an output voltage command to perform, and rectangular wave control (for example, 1PLS in the embodiment) An energization mode switching unit (for example, an energization mode switching determination unit 131 in the embodiment) that switches an energization mode performed by the rectangular wave inverter, and a change amount of the target DC voltage of the voltage conversion unit is predetermined. When the condition is satisfied, the energization mode switching unit switches the energization mode to two-phase energization with dead time, and the output voltage command generation unit is configured to supply the rectangular wave current or the rectangular wave voltage supplied to the electric motor. Generating the output voltage command instructing stepwise step-up or step-down toward the target DC voltage in synchronization with the change of the voltage, the voltage conversion unit according to the output voltage command, during the dead time The output voltage of the DC power supply is boosted or lowered .

Furthermore, in the motor control device according to the third aspect of the present invention, a voltage detection unit (for example, the output voltage detection unit 125 in the embodiment) that detects an output voltage of the voltage conversion unit is provided, and the voltage detection unit When the difference between the detected voltage and the target DC voltage is equal to or less than a predetermined value, the energization mode switching unit switches to the energization mode before switching to the two-phase energization with dead time.

Furthermore, in the motor control apparatus according to claim 4 , the target DC voltage includes a required output power derived based on a torque required for the motor and an angular velocity of the rotor, and the voltage conversion unit. It is the value obtained according to the difference of the actual output power derived | led-out based on the output voltage and output current of this.

According to the electric motor control device of the first to fourth aspects of the invention, the electric motor is not affected by the overshoot that occurs when the voltage conversion unit steps up or down. Therefore, the electric motor can operate with high operation efficiency.

The block diagram which shows the control apparatus of the electric motor of one Embodiment 1 is a block diagram showing a part of the motor control device shown in FIG. 1 and each circuit of a DCDC converter and an inverter. The graph which shows each phase voltage which the inverter 117 applies to the electric motor 10 at the time of three-phase electricity supply The graph which shows each phase voltage which the inverter 117 applies to the electric motor 10 at the time of two-phase electricity supply with a dead time for the electrical angle of about 10 degrees As a part of the motor control device shown in FIG. 1, a block diagram showing the internal configurations of the output voltage command generation unit 121 and the inverter calculation method determination unit 129, and the relationship with components related thereto. The block diagram which shows the internal structure of the target DC voltage command generation part 301 which the output voltage command generation part 121 has In the motor control device shown in FIG. 1, when the amount of change per unit time of the target DC voltage command Vcu ** generated by the target DC voltage command generation unit 301 of the output voltage command generation unit 121 exceeds the threshold value. (A) Phase currents supplied to the motor 10 by the inverter 117, (b) Phase voltages applied to the motor 10 by the inverter 117, (c) Target DC voltage command Vcu ** and voltage of the output voltage command generator 121 Graph showing output voltage command Vcu *** output from command output unit 303 and (d) output voltage Vdc of DCDC converter 123 The block diagram which shows the load drive device disclosed by patent document 1

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram illustrating an electric motor control apparatus according to an embodiment. FIG. 2 is a block diagram showing a part of the motor control device shown in FIG. 1 and each circuit of the DCDC converter and the inverter. 1 includes a resolver 101, a current sensor 103, a bandpass filter (BPF) 105, a three-phase-dp converter 107, a current command calculator 109, and a d-axis current controller 111. A q-axis current control unit 113, an rθ conversion unit 115, an inverter (INV) 117, an angular velocity calculation unit 119, an output voltage command generation unit 121, a DCDC converter 123, an output voltage detection unit 125, and an output A current detection unit 127, an inverter calculation method determination unit 129, and an energization mode switching determination unit 131 are provided.

  Electric power is supplied from the battery 15 to the electric motor 10 shown in FIG. 1 via the control device. The electric motor 10 is, for example, a three-phase brushless DC motor that includes a rotor having permanent magnets and a stator that rotates a rotor by generating a rotating magnetic field using two-phase or three-phase applied voltages.

  The resolver 101 detects the mechanical angle of the rotor of the electric motor 10 and outputs an electrical angle θm corresponding to the detected mechanical angle. The electrical angle θm output from the resolver 101 is sent to the three-phase-dp converter 107 and the angular velocity calculator 119. The current sensor 103 detects each phase current of the three-phase current supplied from the inverter 117 and supplied to the stator of the electric motor 10.

  The BPF 105 removes unnecessary components of each current detection signal indicating the three-phase alternating currents Iu, Iv, Iw detected by the current sensor 103. The three-phase-dp conversion unit 107 performs three-phase-dq conversion based on the current detection signal from which unnecessary components have been removed by the BPF 105 and the electrical angle θm of the rotor detected by the resolver 101, and the d-axis current Detection value Id_s and q-axis current detection value Iq_s are calculated.

  The current command calculator 109 is a current (hereinafter referred to as “d-axis current”) that flows through a d-axis side stator (hereinafter referred to as “d-axis stator”) based on a torque command value T input from the outside. Command value Id * and a command value Iq * of a current (hereinafter referred to as “q-axis current”) flowing through a q-axis side stator (hereinafter referred to as “q-axis stator”). The d-axis current command value Id * is input to the d-axis current control unit 111. Further, the q-axis current command value Iq * is input to the q-axis current control unit 113. The d axis is a field axis, and the q axis is a torque axis.

  The d-axis current control unit 111 has a command value Vd for the voltage across the terminals of the d-axis stator (hereinafter referred to as “d-axis voltage”) so that the deviation ΔId between the command value Id * of the d-axis current and the detected value Id_s decreases. Determine **. The q-axis current control unit 113 controls the command value Vq of the inter-terminal voltage of the q-axis stator (hereinafter referred to as “q-axis voltage”) so that the deviation ΔIq between the q-axis current command value Iq * and the detected value Iq_s decreases. Determine **. The d-axis voltage command value Vd ** and the q-axis voltage command value Vq ** are input to the rθ conversion unit 115 and the inverter calculation method determination unit 129.

  The rθ conversion unit 115 converts the command value Vd ** of the d-axis voltage and the command value Vq ** of the q-axis voltage into components of the voltage level V1 and the angle θ.

  The inverter 117 converts the DC voltage from the battery 15 via the DCDC converter 123 into a three-phase (U, V, W) AC voltage based on the voltage level V1 and the angle θ component input from the rθ converter 115. Convert. The inverter 117 is a rectangular wave inverter, and performs PWM (Pulse Width Modulation) control or one-pulse (1PLS) control according to the switching flag input from the inverter calculation method determination unit 129. Note that the PWM control can control the output voltage of the inverter 117 with higher accuracy as the switching frequency is higher. On the other hand, 1PLS control has a small switching loss because the switching frequency is low.

  Note that, during the 1PLS control, the inverter 117 performs three-phase energization or two-phase energization with dead time for the electric motor 10. FIG. 3 is a graph showing each phase voltage applied to the electric motor 10 by the inverter 117 during three-phase energization. FIG. 4 is a graph showing each phase voltage applied by the inverter 117 to the electric motor 10 during two-phase energization with a dead time corresponding to an electrical angle of about 10 degrees.

  The angular velocity calculation unit 119 calculates the angular velocity ω of the rotor of the electric motor 10 by time differentiation of the electrical angle θm output from the resolver 101. The angular velocity ω calculated by the angular velocity calculation unit 119 is input to the DC voltage command generation unit 121.

  The output voltage command generator 121 generates an output voltage command Vcu *** to be input to the DCDC converter 123. As shown in FIGS. 1 and 2, the output voltage command generation unit 121 includes a torque command value T input from the outside, an angular velocity ω calculated by the angular velocity calculation unit 119, and an electrical angle output from the resolver 101. θm, the output voltage Vdc of the DCDC converter 123 detected by the output voltage detection unit 125, and the output current Idc of the DCDC converter 123 detected by the output current detection unit 127 are input.

  The DCDC converter 123 is a step-up / down converter as shown in FIG. The DCDC converter 123 boosts or steps down the direct current output voltage of the battery 15 with direct current in accordance with the command Vcu *** from the output voltage command generator 121. The output voltage detector 125 detects the output voltage Vdc of the DCDC converter 123. The output current detection unit 127 detects the output current Idc of the DCDC converter 123.

  The inverter calculation method determination unit 129 includes the output voltage Vdc of the DCDC converter 123, the command value Vd ** of the d-axis voltage output from the d-axis current control unit 111, and the q-axis output from the q-axis current control unit 113. Based on the voltage command value Vq **, a PWM / 1PLS switching flag to be input to the inverter 117 is determined.

  FIG. 5 shows each internal configuration of the output voltage command generation unit 121 and the inverter calculation method determination unit 129 as a part of the control device of the electric motor 10 shown in FIG. 1 and the relationship with the related components. It is a block diagram. As shown in FIG. 5, the inverter calculation method determination unit 129 includes a maximum voltage circle calculation unit 201, an output voltage circle calculation unit 203, and a switching flag output unit 205. The maximum voltage circle calculation unit 201 derives a value (Vdc / √6) Vp_target obtained by dividing the output voltage Vdc of the DCDC converter 123 by √6. This value Vp_target is the maximum value of the phase voltage that can be applied to the electric motor 10, that is, the phase voltage value that is applied to the electric motor 10 with the duty ratio in the inverter 117 being 100%.

The output voltage circle calculation unit 203 derives the calculation result of √ (Vd ** ² + Vq ** ² ) as a combined vector voltage Vp. The switching flag output unit 205 performs PWM / 1PLS switching according to the difference ΔVp (= Vp_target−Vp) between the value Vp_target derived by the maximum voltage circle calculation unit 201 and the combined vector voltage Vp derived by the output voltage circle calculation unit 203. Output a flag. The switching flag output unit 205 outputs a switching flag indicating PWM control when the difference ΔVp is greater than 0 (ΔVp> 0), and outputs a flag indicating 1PLS control when the difference ΔVp is 0 or less (ΔVp ≦ 0). To do. The PWM / 1PLS switching flag output from the switching flag output unit 205 is input to the inverter 117.

  As shown in FIG. 5, the output voltage command generation unit 121 includes a target DC voltage command generation unit 301 and a voltage command output unit 303. As shown in FIGS. 1, 2, and 5, the output voltage command generation unit 121 includes a torque command value T input from the outside, an angular velocity ω calculated by the angular velocity calculation unit 119, and a resolver 101. The output electrical angle θm, the output voltage Vdc of the DCDC converter 123 detected by the output voltage detection unit 125, the output current Idc of the DCDC converter 123 detected by the output current detection unit 127, and the energization mode switching determination unit 131 output The two-phase energization / 3-phase energization switching flag is input.

  FIG. 6 is a block diagram illustrating an internal configuration of the target DC voltage command generation unit 301 included in the output voltage command generation unit 121. As shown in FIG. 6, the target DC voltage command generation unit 301 multiplies the coefficient K, the torque command value T, and the angular velocity ω to derive the required output power P0. The target DC voltage command generation unit 301 multiplies the output current Idc of the DCDC converter 123 by the output voltage Vdc to derive the actual output power P1. The target DC voltage command generation unit 301 generates a target DC voltage command Vcu ** as a control amount of PI control according to the difference ΔP (= P0−P1) between the requested output power P0 and the actual output power P1. The target DC voltage command Vcu ** is input to the voltage command output unit 303.

  The voltage command output unit 303 increases the voltage stepwise toward the target DC voltage in synchronization with the electrical angle θm of the rotor of the electric motor 10 when the energization mode switching determination unit 131 outputs a flag indicating two-phase energization. An output voltage command Vcu *** that instructs the DCDC converter 123 to output is output. On the other hand, when the energization mode switching determination unit 131 outputs a flag indicating three-phase energization, the voltage command output unit 303 outputs the target DC voltage command Vcu ** generated by the target DC voltage command generation unit 301 as the output voltage. Output as command Vcu ***. The output voltage command Vcu *** output from the voltage command output unit 303 is input to the DCDC converter 123.

  Based on the amount of change in the target DC voltage command Vcu ** generated by the target DC voltage command generation unit 301 of the output voltage command generation unit 121, the power supply mode switching determination unit 131 instructs the power supply mode of the inverter 117 during 1PLS control. Change the switching flag (2-phase energization / 3-phase energization switching flag). As described above, the inverter 117 during the 1PLS control performs three-phase energization or two-phase energization with dead time for the electric motor 10.

  As shown in FIGS. 1, 2, and 5, the energization mode switching determination unit 131 includes an electrical angle θm output from the resolver 101, an output voltage Vdc of the DCDC converter 123 detected by the output voltage detection unit 125, and The target DC voltage command Vcu ** generated by the target DC voltage command generation unit 301 of the output voltage command generation unit 121 and the output voltage command Vcu *** output by the voltage command output unit 303 of the output voltage command generation unit 121 are input. Is done. When the change amount per unit time of the target DC voltage command Vcu ** generated by the voltage command output unit 303 exceeds a threshold value, the energization mode switching determination unit 131 dead the energization mode performed by the inverter 117 during 1PLS control. Switch to 2-phase energization with time. At this time, the energization mode switching determination unit 131 outputs a switching flag indicating two-phase energization. In addition, when the difference between the target DC voltage command Vcu ** and the output voltage Vdc of the DCDC converter 123 is equal to or less than a threshold value, the energization mode switching determination unit 131 changes the energization mode performed by the inverter 117 during 1PLS control to three-phase energization. return. At this time, the energization mode switching determination unit 131 outputs a switching flag indicating three-phase energization. The two-phase energization / 3-phase energization switching flag output from the energization mode switching determination unit 131 is input to the inverter 117 and the voltage command output unit 303 of the output voltage command generation unit 121.

  FIG. 7 shows the threshold value of the amount of change per unit time of the target DC voltage command Vcu ** generated by the target DC voltage command generation unit 301 of the output voltage command generation unit 121 in the control device for the electric motor 10 shown in FIG. When the value exceeds (a) each phase current supplied by the inverter 117 to the motor 10, (b) each phase voltage applied by the inverter 117 to the motor 10, (c) a target DC voltage command Vcu ** and an output voltage command It is a graph which shows the output voltage command Vcu *** which the voltage command output part 303 of the production | generation part 121 outputs, and the output voltage Vdc of the (d) DCDC converter 123. FIG. As shown in FIG. 7C, when the target DC voltage command Vcu ** changes sharply and the amount of change per unit time exceeds a threshold value, the energization mode switching determination unit 131 performs 1PLS control. The current supply mode of the inverter 117 is switched to two-phase power supply with dead time.

  At this time, as shown in FIG. 7B, each phase voltage having a conduction angle of 120 degrees or less is applied to the inverter 117. FIG. 7B shows an example in which the conduction angle is 110 degrees. As a result, as shown in FIG. 7A, the inverter 117 supplies each phase current having a dead time of 20 degrees (a time during which no current is supplied to the electric motor 10) to the electric motor 10 for every electric angle θm of 60 degrees. To do. As shown in FIG. 7C, the output voltage command generation unit 121 increases the output voltage Vdc of the DCDC converter 123 stepwise toward the target DC voltage in synchronization with the electrical angle that is the dead time. Outputs Vcu ***. As a result, the DCDC converter 123 outputs the voltage Vdc shown in FIG. 7D according to the output voltage command Vcu ***.

  As shown in FIG. 7D, when the DCDC converter 123 boosts the voltage according to the output voltage command Vcu ***, an overshoot occurs in the output voltage Vdc. However, as shown in FIG. 7, overshoot occurs during the dead time. Therefore, the electric motor 10 is not affected by the overshoot generated in the output voltage Vdc of the DCDC converter 123.

  As described above, according to the motor control device of this embodiment, when the amount of change per unit time of the target DC voltage command Vcu ** exceeds the threshold, the energization mode performed by the inverter 117 during 1PLS control. Is switched to two-phase energization with a dead time, and the DCDC converter 123 performs a boosting operation during the dead time. Therefore, the electric motor 10 is not affected by the overshoot generated in the output voltage Vdc of the DCDC converter 123. As a result, the electric motor 10 can operate with high operating efficiency.

  In the above embodiment, since the output voltage command Vcu *** is synchronized with the dead time, the output voltage command generation unit 121 uses the electrical angle θm of the rotor of the electric motor 10, but the current sensor 103 The detected three-phase current supplied to the stator of the electric motor 10 may be used. In addition, as shown to Fig.7 (a), the area where all the three-phase currents are zero is a dead time. Further, a three-phase voltage applied to the stator of the electric motor 10 may be used. In addition, as shown in FIG.7 (b), the area where the voltage of 2 phases is zero among 3 phases is a dead time.

  FIG. 7 shows a case where the DCDC converter 123 performs a step-up operation, but the same applies to the case where the DCDC converter 123 steps down. Further, in the above embodiment, the DCDC converter 123 is a step-up / step-down converter, but it may be a step-up converter or a step-down converter.

DESCRIPTION OF SYMBOLS 10 Electric motor 15 Capacitor 101 Resolver 103 Current sensor 105 Band pass filter (BPF)
107 three-phase-dp conversion unit 109 current command calculation unit 111 d-axis current control unit 113 q-axis current control unit 115 rθ conversion unit 117 inverter 119 angular velocity calculation unit 121 output voltage command generation unit 123 DCDC converter 125 output voltage detection unit 127 output Current detection unit 129 Inverter calculation method determination unit 131 Energization mode switching determination unit 201 Maximum voltage circle calculation unit 203 Output voltage circle calculation unit 205 Switching flag output unit 301 Target DC voltage command generation unit 303 Voltage command output unit

Claims (4)

A control device for an electric motor having a rotor, and a stator that rotates a rotor by generating a rotating magnetic field by an applied voltage,
A rectangular wave inverter that drives the electric motor by applying a rectangular wave voltage to the stator of the electric motor;
A voltage converter for stepping up or stepping down the output voltage of the DC power source and applying it to the rectangular wave inverter;
An output voltage command generator for generating an output voltage command for instructing an output voltage of the voltage converter;
An energization mode switching unit that switches an energization mode performed by the rectangular wave inverter during rectangular wave control;
An electrical angle acquisition unit that acquires an electrical angle of the rotor of the electric motor,
When the amount of change in the target DC voltage of the voltage converter satisfies a predetermined condition, the energization mode switching unit switches the energization mode to two-phase energization with dead time, and the output voltage command generation unit Generating the output voltage command for instructing stepwise voltage step-up or step-down toward the target DC voltage in synchronization with a change in the electric angle of the rotor acquired by the electric angle acquisition unit ;
The voltage control unit boosts or steps down the output voltage of the DC power supply during a dead time according to the output voltage command . A control device for an electric motor having a rotor, and a stator that rotates a rotor by generating a rotating magnetic field by an applied voltage,
A rectangular wave inverter that drives the electric motor by applying a rectangular wave voltage to the stator of the electric motor;
A voltage converter for stepping up or stepping down the output voltage of the DC power source and applying it to the rectangular wave inverter;
An output voltage command generator for generating an output voltage command for instructing an output voltage of the voltage converter;
An energization mode switching unit that switches an energization mode performed by the rectangular wave inverter during rectangular wave control,
When the amount of change in the target DC voltage of the voltage converter satisfies a predetermined condition, the energization mode switching unit switches the energization mode to two-phase energization with dead time, and the output voltage command generation unit Generating the output voltage command for instructing stepwise step-up or step-down toward the target DC voltage in synchronization with a change in the rectangular wave current or the rectangular wave voltage supplied to the electric motor ;
The voltage control unit boosts or steps down the output voltage of the DC power supply during a dead time according to the output voltage command . The motor control device according to claim 1 or 2 ,
A voltage detector for detecting an output voltage of the voltage converter;
When the difference between the voltage detected by the voltage detection unit and the target DC voltage is equal to or less than a predetermined value, the energization mode switching unit switches to the energization mode before switching to the two-phase energization with dead time. Electric motor control device. It is a control device of the electric motor according to any one of claims 1 to 3 ,
The target DC voltage is the required output power derived based on the torque required for the motor and the angular velocity of the rotor, and the actual output power derived based on the output voltage and output current of the voltage converter. An electric motor control device characterized in that the value is obtained according to the difference.

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