JP2006340448A - Electric motor control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a converter output voltage significantly in a low speed region as compared with the conventional one and to reduce a DC link voltage in a wider range than conventional.
A converter control circuit performs DC / DC conversion control on a DC / DC converter so that a DC link voltage becomes a target voltage value corresponding to the speed of the AC motor according to a predetermined characteristic curve. Do. At this time, since the target voltage in the low speed region where the DC link voltage is minimum is lower than the output voltage of the DC source 1, the switching loss suppression effect in the VVVF inverter 4 can be improved.
[Selection] Figure 1

Description

  The present invention relates to an electric motor control device that converts direct current power from a DC / DC converter into alternating current power that is subjected to variable voltage variable frequency control by a VVVF inverter, and outputs the converted alternating current power to an alternating current motor.

  In railway vehicles such as trains or hybrid vehicles, a converter DC / DC converts DC power output from a DC power source such as an overhead wire or a fuel cell, and an inverter converts the DC / DC converted DC power. A general configuration is such that the AC voltage is converted into AC power controlled by variable voltage and variable frequency, and the AC power is output to the AC motor.

  By the way, when the inverter performs the above variable voltage variable frequency control, the switching element must be switched at a high frequency, so that a switching loss occurs. In order to reduce energy loss during vehicle travel and extend the vehicle travel distance, it is important to suppress the occurrence of this switching loss as much as possible.

Since the above switching loss becomes remarkable in the low speed region of the AC motor, a technique for reducing the output voltage of the converter (that is, the input voltage of the inverter) has been conventionally employed in the low speed region (for example, Patent Document 1). reference).
Japanese Patent Publication No. 7-32607

  However, in the prior art, the converter output voltage is reduced to the level of the input voltage of the DC source at most, and the range in which the converter output voltage can be reduced is not so wide. The effect of suppressing the generation of switching loss could not be sufficiently obtained.

  The present invention has been made in view of the above circumstances, and in the low-speed region, the converter output voltage can be greatly reduced as compared with the conventional case, and the range in which the converter output voltage can be reduced as compared with the conventional case is widened. An object of the present invention is to provide a possible motor control device.

  As means for solving the above-mentioned problems, the invention described in claim 1 includes a DC / DC converter for DC / DC converting DC power from a DC source, and DC voltage from the DC / DC converter with variable voltage variable frequency. The VVVF inverter that converts into controlled AC power and outputs it to the AC motor, and the DC link voltage on the DC / DC converter output side or the VVVF inverter input side become a target voltage value corresponding to the speed of the AC motor. In the electric motor control device comprising a converter control circuit for performing DC / DC conversion control and an inverter control circuit for performing variable voltage variable frequency control on the VVVF inverter, the DC / DC converter can be stepped down. In the low speed region where the speed of the AC motor is a predetermined value or less, the DC link voltage is the DC source. As the output voltage or less, to lower the target voltage of the DC link voltage according to the speed, characterized in that.

  According to a second aspect of the present invention, there is provided a DC / DC converter for DC / DC converting DC power from a DC source, and an AC motor by converting DC power from the DC / DC converter into AC power with variable voltage and variable frequency control. And a converter control circuit for performing DC / DC conversion control so that the DC link voltage on the DC / DC converter output side or the VVVF inverter input side becomes a target voltage corresponding to the speed of the AC motor. And an inverter control circuit that performs variable voltage variable frequency control on the VVVF inverter so that torque that matches an external torque command is output from the AC motor, the target voltage is: The DC link voltage is set to be equal to or lower than the rated operating voltage of the DC / DC converter. It is obtained by the converter control circuit inputs a torque command from the outside, characterized in that.

  According to a third aspect of the present invention, in the second aspect of the invention, the VVVF inverter performs the variable voltage variable frequency control based on vector control. When the torque command changes, the torque In response to the command, not only the torque current Iq but also the magnetizing current Id is changed, thereby enabling the converter control circuit to control the DC link voltage to be equal to or lower than the rated operating voltage of the DC / DC converter. It is characterized by that.

  The invention according to claim 4 is the invention according to claim 3, wherein the AC motor is an induction motor, and the magnetizing current Id is made equal to the torque current Iq.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, a characteristic curve between the target voltage and the speed of the AC motor for the DC link voltage has a DC link voltage level of A first region that is constant and minimum level, a second region where the DC link voltage level gradually increases from the minimum level to the maximum level, and a first region that becomes constant after the DC link voltage level reaches the maximum level. And 3 regions.

  According to a sixth aspect of the present invention, in the fifth aspect of the invention, the VVVF inverter determines the number of switchings within one period of the fundamental wave in the second and third regions as one period of the fundamental wave of the first region. It controls to become smaller than the number of times of switching.

  The invention according to claim 7 is the invention according to claim 6, wherein the VVVF inverter performs the variable voltage variable frequency control based on a one-pulse mode in the second and third regions. And

  The invention according to claim 8 is the invention according to any one of claims 1 to 7, wherein the DC / DC converter is configured to be capable of two-quadrant operation, and the regenerative power from the VVVF inverter side is supplied to the DC source. It can be regenerated on the side.

  The invention according to claim 9 is the invention according to any one of claims 1 to 7, wherein the DC / DC converter is a step-down chopper type converter, and the maximum level of the DC link voltage is set to the output voltage of the DC source. It is characterized by being equal.

  According to a tenth aspect of the present invention, in the invention according to any one of the first to ninth aspects, the AC motor is a train motor, and the DC source is an overhead wire.

  According to an eleventh aspect of the present invention, in the invention according to any one of the first to ninth aspects, the DC source is a fuel cell or a secondary battery.

  According to the present invention, the target voltage in the low speed region where the DC link voltage is minimized can be set lower than the output voltage of the DC source, or the DC link voltage can be reduced over a wide range. The switching loss suppression effect can be improved as compared with the conventional case.

  FIG. 1 is a configuration diagram of an electric motor control device according to a first embodiment of the present invention. The direct current power from the direct current source 1 is output to the DC / DC converter 2 and is DC / DC converted by the DC / DC converter 2. This DC / DC converted DC power is output to the VVVF inverter 4 via the smoothing capacitor 3. The VVVF inverter 4 converts the input DC power into AC power subjected to variable voltage variable frequency control and outputs the AC power to the AC motor 5.

  Here, in this specification, the output side voltage of the DC / DC converter 2 or the input side voltage of the VVVF inverter 4, that is, the voltage across the smoothing capacitor 3 is referred to as “DC link voltage”. The voltage detector 6 detects the DC link voltage. The voltage detector 7 detects the output side voltage of the VVVF inverter 4, that is, the motor applied voltage of the AC motor 5. The speed of the AC motor 5, that is, the number of revolutions per unit time is detected by the speed detector 8.

  The converter control circuit 9 performs DC / DC conversion so that the DC link voltage becomes a target voltage corresponding to the speed of the AC motor 5, and the detection signals from the voltage detector 6 and the speed detector 8 are fed back as feedback signals. Is supposed to be entered as The converter control circuit 9 includes a DC voltage command calculation unit 10, an adder 11, a voltage control unit 12, and a PWM control unit 13.

  The inverter control unit 14 performs variable voltage variable frequency control on the VVVF inverter 4 so that torque matching the torque command from the outside is output from the AC motor 5. The voltage detector 7 and the speed detector The detection signal from 8 is input as a feedback signal.

  FIG. 2 is an explanatory diagram showing a specific example of the DC source 1 in FIG. The DC source 1 in FIG. 2A is used for a railway vehicle such as a train, and a P line is connected to a pantograph 16 that collects DC power from the overhead line 15, and an N line is on a track 17. The wheels 18 that travel on the road are connected. In the case of the direct current source 1 for trains, direct current power is normally output to the DC / DC converter 2 via an LC filter including a reactor 19 and a capacitor 20.

  The DC source 1 shown in FIG. 2B is mainly used for small vehicles such as automobiles, and is composed of a fuel cell or a secondary battery. Recently, however, research and development have been conducted on the use of a direct current source composed of a fuel cell or a secondary battery not only for small vehicles such as automobiles but also for large vehicles of the railway vehicle class.

  FIG. 3 is a circuit configuration diagram of the DC / DC converter 2 in FIG. As shown in this figure, diodes D1 to D4 are connected in reverse parallel to the switching elements SW1 to SW4, one arm is formed by the switching elements SW1 and SW3 connected in series, and the switching elements SW2 connected in series. , SW4 forms the other arm. And each center part of these both arms is connected via the reactor L1.

  The DC / DC converter 2 is a buck-boost chopper type converter, and functions as a converter capable of two-quadrant operations of power running and regeneration. That is, in the case of power running, the switching element SW4 is turned on and off (at this time, the switching elements SW2 and SW3 are in the off state and SW1 is in the on state). Thereby, the electric energy from the DC source 1 accumulated in the reactor L1 when the switching element SW4 is turned on is released to the smoothing capacitor 3 side through the diode D2 functioning as a freewheeling diode. Therefore, the voltage of the smoothing capacitor 3 increases.

  On the other hand, in the case of regeneration, the switching element SW3 is turned on and off (at this time, the switching elements SW1 and SW4 are in the off state and SW2 is in the on state). Thereby, the electric energy from the smoothing capacitor 3 accumulated in the reactor L1 when the switching element SW3 is turned on is released to the DC source 1 side through the diode D1 functioning as a freewheeling diode. By adjusting the on-time described above, it is possible to continuously switch between step-up and step-down.

  FIG. 4 is a characteristic diagram showing the relationship between the DC link voltage set as the target voltage of the DC / DC converter 2 and the speed of the AC motor 5. As shown in this figure, the characteristic curve has a first region R1 where the level is constant and the minimum level, a second region R2 which gradually increases from the minimum level to the maximum level, and a constant level after reaching the maximum level. (The DC link voltage in the third region R3 is the rated operating voltage of the DC / DC converter 2 and the VVVF inverter 4). The converter control circuit 9 controls the DC / DC converter 2 so as to obtain the characteristics shown in FIG.

  Next, the operation of FIG. 1 will be described. The converter control circuit 9 starts control on the DC / DC converter 2 based on an input of an operation start command from the outside. That is, the direct-current voltage command calculation unit 10 stores the characteristics shown in FIG. 4 and outputs a voltage command that initially becomes the voltage level of the first region R1. The adder 11 outputs a deviation between the command voltage from the DC voltage command calculation unit 10 and the detection voltage from the voltage detector 6 to the voltage control unit 12. The voltage control unit 12 outputs a voltage control signal to the PWM control unit 13 so that the deviation becomes zero. Then, the PWM control unit 13 outputs a control signal (gate signal) for performing PWM control based on the voltage control signal to the switching elements SW1 to SW4 of the DC / DC converter 2.

  Based on the control signal from the converter control circuit 9, the DC / DC converter 2 initially performs an operation of stepping down the output voltage of the DC source 1 to the level of the first region R1. Then, after the speed of the AC motor 5 has increased to a certain level or higher, an operation of increasing the output voltage of the DC source 1 along the second region R2 is performed, and when the speed of the AC motor 5 is further increased, The operation of maintaining the output voltage of 1 at a constant level in the third region R3 is performed.

  On the other hand, the inverter control unit 14 performs switching control on the switching elements in the VVVF inverter 4 so that the output torque of the AC motor 5 matches the torque command, and performs variable voltage variable frequency control of the VVVF inverter 4.

  In this case, the inverter control unit 14 makes the number of switchings within one period of the fundamental wave in the second region R2 and the third region R3 smaller than the number of switchings within one period of the fundamental wave in the first region R1. Perform switching control. That is, it is inevitable that the number of switching increases to some extent in the first region R1 where the speed of the AC motor 5 is the low speed region, but the number of switching is reduced in the other second and third regions R2, R3. Therefore, it is preferable to reduce the switching loss of the VVVF inverter 4. Preferably, the operation is performed in a so-called one-pulse mode in which the number of switching pulses is one in the second and third regions R2 and R3.

  Even in the conventional device (for example, the device according to the patent document), control is performed to reduce the DC link voltage in a low speed region where the speed of the AC motor 5 is below a certain level. Since it was the level of the output voltage, the effect of reducing the switching loss of the VVVF inverter 4 was not necessarily sufficient. On the other hand, in the configuration of FIG. 1, as described above, the DC / DC converter 2 performs control so that the DC link voltage is equal to or lower than the DC source output voltage in the low speed region, so that the VVVF inverter 4 has the switching loss in the low speed region. Can be sufficiently reduced.

  FIG. 5 is a configuration diagram of an electric motor control device according to the second embodiment of the present invention. 5 differs from FIG. 1 in that an external torque command is input not only to the inverter control unit 14 but also to the DC voltage command calculation unit 10 of the converter control circuit 9. The converter control circuit 9 controls the DC link voltage level in accordance with the torque command.

  In addition, the inverter control unit 14 in the second embodiment is premised on performing variable voltage variable frequency control based on vector control, and when the torque command from the outside is smaller than a predetermined value, Accordingly, not only the torque current Iq but also the magnetizing current Id is changed.

  FIG. 6 is a characteristic diagram showing the relationship between the DC link voltage set as the target voltage of the DC / DC converter 2 in FIG. 5 and the speed of the AC motor 5. In this figure, the DC link voltage in the third region R3 is the rated operating voltage of the DC / DC converter 2 as in the case of FIG.

  Unlike the case of FIG. 4, the characteristic diagram of FIG. 6 has the same level as that of the conventional apparatus because the DC link voltage in the first region R1 is at the same level as the DC source output voltage. appear. However, the first region R1 in FIG. 6 is actually an expanded region as compared with the conventional device, and this embodiment improves the switching loss reduction effect of the VVVF inverter 4 by that amount. Is possible. Thus, the reason why the first region R1 can be expanded is that the same torque can be obtained in a state where the output voltage of the VVVF inverter 4, that is, the applied voltage of the AC motor 5, is lower than that of the conventional device.

  Next, the basic principle that is the basis for obtaining the same torque with the motor applied voltage lower than that of the conventional apparatus as described above will be described. FIG. 7 is an equivalent circuit diagram of the AC motor 5 (in the case of an induction motor). As shown in this figure, the induction motor has a primary resistance R1, a primary self-inductance L1, a secondary resistance R2, and a secondary self-inductance L2.

When the torque current in vector control is Iq, the magnetizing current is Id, the torque is T, the mutual inductance is M, and the secondary magnetic flux is Φ, the torque T is expressed by the following equation (1).
T = (M / L2) ・ Iq ・ Φ2 (1)

Here, since there is a relationship of Φ2 = M · Id, equation (1) is expressed as equation (2).
T = (M ² / L ² ) · Iq · Id (2)

  In a normal induction motor, the ratio of Iq to Id at the maximum torque is about 3: 1 (this ratio corresponds to the ratio of copper to iron in the induction motor). In the vector control, when the torque command is changed, in order to obtain a good torque response, only the torque current Iq is changed, and the magnetizing current Id is normally kept constant.

  Therefore, the combined current vector of the torque current Iq and the magnetizing current Id corresponding to a certain torque command is shown in FIG. 8A. If this torque command is changed to a small one, the combined device after the change in the conventional apparatus The current vector is expressed as shown in FIG. As is clear from comparison of FIG. 8B with FIG. 8A, only the torque current Iq is small, and the magnetizing current Id is not changed.

  However, according to the equation (2), even if both Iq and Id are changed without keeping Id constant, the same torque as after the torque command change should be obtained. Therefore, in this embodiment, when the torque command changes, control is performed not to change only Iq as shown in FIG. 8B but to change both Iq and Id as shown in FIG. 8C. I have to. And according to the control which concerns on such FIG.8 (c), the applied voltage of the alternating current motor 5 can be made lower than the control which concerns on conventional FIG.8 (b).

That is, when the motor rotation frequency is ωr, the induced voltage E is expressed by the equation (3), and it is clear that E decreases as Id decreases.
E = (M / L2) ・ Φ2 ・ ωr
= (M / L2) ・ (M ・ Id) ・ ωr
= (M ² / L ² ) · Id · ωr (3)

  However, the applied voltage V1 of the AC motor 5 is not determined only by the induced voltage E, but is expressed as the voltage drop of the primary resistance R1 and the primary leakage inductance σL1 added to the induced voltage E. However, since the induced voltage E is at a level much higher than these voltage drops (for example, the ratio of the induced voltage E to the voltage drop of σL1 is about 10: 1), the motor is applied substantially. The voltage V1 can be regarded as being determined by the induced voltage E.

  FIGS. 9A and 9B show vectors of the induced voltage E and the motor applied voltage V1 on the dq axis coordinates of FIGS. 8A and 8B, respectively. The induced voltage E in FIG. 9 (b) is lower than the induced voltage E in FIG. 9 (a). Therefore, the motor applied voltage V1 in FIG. 9 (b) is also lower than the motor applied voltage V1 in FIG. 9 (a). It is clear that it is lower. As shown in FIG. 9B, this is due to the fact that the magnetizing current Id in FIG. 9A is reduced and the torque current Iq is increased.

In the case of FIG. 9B (in the case of FIG. 8C), Id = Iq is substantially satisfied. Thus, by making the magnetizing current Id substantially equal to the torque current Iq, the current flowing through the induction motor can be minimized, and the loss of the induction motor can be reduced. This is because the loss Ploss of the induction motor is expressed by the equation (4), and normally the value of Ploss is almost the minimum when Id = Iq.
Ploss = R 1 (Id ² + Iq ² ) + (M / L ² ) ² · R 2 · Iq ² (4)

  FIG. 10 is a diagram illustrating the characteristic diagram of the present embodiment shown in FIG. 6 in comparison with the characteristic diagram of the conventional apparatus, and clarifying the difference between the two. As shown in this figure, the first region R1 in this embodiment is enlarged by R11 as compared with the low speed region R10 of the conventional device. Therefore, it is possible to control the DC link voltage to be the same as the DC source output voltage, which is the minimum voltage, even at a speed where the DC link voltage had to be equal to or higher than the DC source output voltage.

  Incidentally, in the second embodiment, it is assumed that the step-up / step-down chopper type converter as shown in FIG. 3 is used as the DC / DC converter 2 in FIG. 5, but the present invention is not particularly limited to this. Alternatively, for example, a step-up chopper type DC / DC converter 2A as shown in FIG. 11 may be used.

  When the DC / DC converter 2A is used, the switching element SW1 only needs to be kept off in the first region R1, so that the switching loss in the converter can be reduced correspondingly, and the switching The lifetime of the element can be extended.

  Note that the DC / DC converter 2A of FIG. 11 is a one-quadrant converter that can operate only in power running. This configuration is possible for power sources that cannot be regenerated, such as fuel cells. For a regenerative power source such as a train system overhead line or a secondary battery, a two-quadrant converter capable of a regenerative operation may be configured. These are well-known techniques.

  Alternatively, a step-down chopper type DC / DC converter 2B as shown in FIG. 12 may be used. However, in this case, it is necessary to use the characteristic diagram shown in FIG. 13 instead of the characteristic diagram shown in FIG. That is, the level of the third region R3 where the DC link voltage is maximum is made the same as the DC source output voltage, and the levels of the first region R1 and the second region R2 are set lower than the DC source output voltage. According to the DC / DC converter 2B, after the operation is started, the switching element SW2 is turned on and off until the DC link voltage reaches the third region R3 via the first region R1 and the second region R2, and the step-down chopper. However, after the DC link voltage reaches the third region R3, the switching element SW2 can be turned on and off, and the switching element SW1 can be kept on. Loss can be reduced and the life of the switching element can be extended.

The block diagram of the electric motor control apparatus which concerns on the 1st Embodiment of this invention. Explanatory drawing which shows the specific example of the DC source 1 in FIG. The circuit block diagram of the DC / DC converter 2 in FIG. FIG. 2 is a characteristic diagram showing the relationship between the DC link voltage set as the target voltage of the DC / DC converter 2 in FIG. 1 and the speed of the AC motor 5. The block diagram of the motor control apparatus which concerns on the 2nd Embodiment of this invention. FIG. 6 is a characteristic diagram showing the relationship between the DC link voltage set as the target voltage of the DC / DC converter 2 in FIG. 5 and the speed of the AC motor 5. The equivalent circuit diagram of the induction motor for demonstrating the basic principle which the 2nd Embodiment of this invention uses. Explanatory drawing which showed the change state of the current vector in the vector control for demonstrating the basic principle which the 2nd Embodiment of this invention uses. Explanatory drawing which showed the change state of the current vector and voltage vector in the vector control for demonstrating the basic principle which the 2nd Embodiment of this invention uses. Explanatory drawing which contrasted and showed the characteristic view based on the 2nd Embodiment of this invention, and the characteristic view of a conventional apparatus. The block diagram about step-up chopper type DC / DC converter 2A which can be used in the 2nd Embodiment of this invention. The block diagram about the step-down chopper type DC / DC converter 2B which can be used in the 2nd Embodiment of this invention. FIG. 13 is a characteristic diagram showing the relationship between the DC link voltage and the speed of the AC motor 5 when the DC / DC converter 2B of FIG. 12 is used.

Explanation of symbols

1 DC source 2 DC / DC converter 2A Step-up chopper type DC / DC converter 2B Step-down chopper type DC / DC converter 3 Smoothing capacitor 4 VVVF inverter 5 AC motor 6 Voltage detector 7 Voltage detector 8 Speed detector 9 Converter control Circuit 10 DC voltage command calculation unit 11 Adder 12 Voltage control unit 13 PWM control unit 14 Inverter control unit 15 Overhead wire 16 Pantograph 17 Track 18 Wheel 19 Reactor 20 Capacitor SW1 to SW4 Switching element D1 to D4 Diode L1 Reactor R1 to R3 First Region to third region

Claims (11)

A DC / DC converter for DC / DC converting DC power from a DC source;
A VVVF inverter that converts DC power from the DC / DC converter into AC power that has been subjected to variable voltage and variable frequency control, and outputs the AC power to an AC motor;
A converter control circuit that performs DC / DC conversion control so that a DC link voltage on the DC / DC converter output side or the VVVF inverter input side has a target voltage value corresponding to the speed of the AC motor;
An inverter control circuit for performing variable voltage variable frequency control on the VVVF inverter;
In an electric motor control device comprising:
The DC / DC converter can be stepped down,
In the low speed region where the speed of the AC motor is a predetermined value or less, the target voltage of the DC link voltage is reduced according to the speed so that the DC link voltage is less than or equal to the output voltage of the DC source.
An electric motor control device. A DC / DC converter for DC / DC converting DC power from a DC source;
A VVVF inverter that converts DC power from the DC / DC converter into AC power that has been subjected to variable voltage and variable frequency control, and outputs the AC power to an AC motor;
A converter control circuit for performing DC / DC conversion control so that a DC link voltage on the DC / DC converter output side or the VVVF inverter input side becomes a target voltage corresponding to the speed of the AC motor;
An inverter control circuit that performs variable voltage variable frequency control on the VVVF inverter so that torque that matches an external torque command is output from the AC motor;
In an electric motor control device comprising:
The target voltage is set so that the DC link voltage is equal to or lower than the rated operating voltage of the DC / DC converter, and the converter control circuit is obtained by inputting a torque command from the outside.
An electric motor control device. The VVVF inverter performs the variable voltage variable frequency control based on vector control,
When the torque command changes, not only the torque current Iq but also the magnetizing current Id is changed according to the torque command,
This enables the converter control circuit to control the DC link voltage to be equal to or lower than the rated operating voltage of the DC / DC converter.
The motor control device according to claim 2, wherein The AC motor is an induction motor,
Making the magnetizing current Id equal to the torque current Iq;
The electric motor control device according to claim 3. A characteristic curve between the target voltage for the DC link voltage and the speed of the AC motor includes a first region where the DC link voltage level is constant and minimum level, and the DC link voltage level is maximum from the minimum level. A second region that gradually increases to a level, and a third region that becomes constant after the DC link voltage level reaches the maximum level.
The motor control device according to claim 1, wherein the motor control device is a motor control device. The VVVF inverter controls the number of switching times in one cycle of the fundamental wave in the second and third regions to be smaller than the number of switching times in one cycle of the fundamental wave in the first region;
The electric motor control device according to claim 5. The VVVF inverter performs the variable voltage variable frequency control based on a one-pulse mode in the second and third regions.
The motor control device according to claim 6. The DC / DC converter is configured to perform a two-quadrant operation, and regenerative power from the VVVF inverter side can be regenerated to the DC source side.
The motor control device according to claim 1, wherein the motor control device is a motor control device. The DC / DC converter is a step-down chopper type converter, and the maximum level of the DC link voltage is made equal to the output voltage of the DC source.
The motor control device according to claim 1, wherein the motor control device is a motor control device. The AC motor is a train motor, and the DC source is an overhead wire.
10. The motor control device according to claim 1, wherein the motor control device is a motor control device. The direct current source is a fuel cell or a secondary battery.
The motor control device according to claim 1, wherein the motor control device is a motor control device.

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