JP2018137909A - Driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress erroneous detection of electric current that flows in a motor connected to an inverter being shut down.SOLUTION: The driving device is provided with: a plurality of motors that are driven by three-phase AC power; a plurality of inverters that drive the plurality of motors; a plurality of three-phase bus bars that connect the plurality of motors with the plurality of inverters; and a controller that controls the plurality of inverters. The plurality of three-phase bus bars are arranged in line, and when shutting down any one of the plurality of inverters, when a threshold is exceeded by electric current that flows in a bus bar of a phase non-adjacent to a three-phase bus bar of a motor connected to an inverter not being shut down in three-phase bus bars of a motor connected to the inverter being shut down, the shutdown of the inverter being shut down is canceled.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a drive device, and more particularly to a drive device including a plurality of motors.

  Conventionally, as this type of drive device, in a hybrid vehicle having two motors, when a phase current flows through the motor that drives one motor while the inverter is shut down, the inverter is released from shutdown. Has been proposed (see, for example, Patent Document 1). When the rotation speed of the motor connected to the inverter that is shut down increases due to being rotated, the back electromotive voltage of the motor becomes larger than the voltage acting on the inverter, and the motor is in a power generation state. At this time, phase current flows through the motor, and torque is output from the motor. In this car, in order to avoid unnecessary torque output from such a motor, when current flows to the motor connected to the inverter that is shut down, the inverter is released from shutdown and no current flows to the motor. Control the inverter.

JP, 2015-020620, A

  In such a drive device including a plurality of motors, a plurality of three-phase bus bars that connect the plurality of motors and the plurality of inverters may be connected in alignment. In this case, the current may be detected by the magnetic field generated by the current flowing in the three-phase bus bar of the motor connected to the non-shutdown inverter in the three-phase bus bar of the motor connected to the inverter that is shut down. . The detection of such a current is an erroneous detection because it is not a current that flows through the motor due to the fact that the counter electromotive voltage of the motor is larger than the voltage acting on the inverter.

  The drive device of the present invention is mainly intended to suppress erroneous detection of a current flowing through a motor connected to an inverter that is shut down.

  The drive device of the present invention employs the following means in order to achieve the main object described above.

The drive device of the present invention is
A plurality of motors driven by three-phase AC power;
A plurality of inverters for driving the plurality of motors;
A plurality of three-phase bus bars connecting the plurality of motors and the plurality of inverters;
A control device for controlling the plurality of inverters;
A drive device comprising:
The plurality of three-phase bus bars are arranged side by side,
When the control device shuts down any one of the plurality of inverters, the control device is connected to an inverter that is not shut down among the three-phase bus bars of the motor that is connected to the shut down inverter. Release the shutdown of the inverter that is shut down when the current flowing in the bus bar of the phase that is not adjacent to the three-phase bus bar of the motor exceeds the threshold,
It is characterized by that.

  In the drive device according to the present invention, a plurality of three-phase bus bars connecting a plurality of motors and a plurality of inverters are arranged in alignment. When any one of the plurality of inverters is shut down, the three-phase motor connected to the non-shutdown inverter among the three-phase bus bars of the motor connected to the shut-down inverter When the current flowing in the bus bar of the phase not adjacent to the bus bar exceeds the threshold, the shutdown of the inverter that is shut down is released. Of the three-phase bus bars of the motor connected to the inverter that is shut down, the bus bars of the phases that are not adjacent to the three-phase bus bar of the motor connected to the inverter that is not shut down are compared to the adjacent bus bars. Therefore, it is difficult to be affected by the current flowing through the three-phase bus bar of the motor connected to the inverter that is not shut down. For this reason, the erroneous detection of the electric current which flows into the motor connected to the inverter which is shut down can be suppressed.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 equipped with a drive device as one embodiment of the present invention. FIG. 3 is a configuration diagram schematically showing an outline of a configuration of a bus bar unit 60. 3 is a flowchart showing an example of a shutdown control routine executed by a motor ECU 40. It is explanatory drawing which shows an example of the time change of rotation speed Nm1 of motor MG1, phase current Iu1, Iw1, the state of the inverter 41, and the presence or absence of execution of zero current control. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 on which a drive device according to a modification is mounted. It is explanatory drawing which shows the bus-bar unit 160 of the drive device of a modification. It is explanatory drawing which shows the bus-bar unit 160 of the drive device of a modification.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 equipped with a drive device as an embodiment of the present invention. The hybrid vehicle 20 of the embodiment includes an engine 22, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50, and a hybrid electronic control unit (hereinafter referred to as HVECU) 70, as shown. .

  The engine 22 is configured as an internal combustion engine that outputs power using gasoline or light oil as a fuel. Operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as engine ECU) 24.

  Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . Signals from various sensors necessary for controlling the operation of the engine 22 are input to the engine ECU 24 via an input port. The signals from the various sensors include, for example, a crank position from a crank position sensor (not shown) that detects the rotational position of the crankshaft 26, a cooling water temperature Tw from a water temperature sensor (not shown) that detects the temperature of cooling water of the engine 22 and the like. Can be mentioned. Further, a throttle opening TH from a throttle valve position sensor (not shown) for detecting the throttle valve position, an intake air amount Qa from an air flow meter (not shown) attached to the intake pipe, and a temperature sensor (not shown) attached to the intake pipe. The intake air temperature Ta can also be mentioned. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 through an output port. Examples of the various control signals include a drive signal to the fuel injection valve, a drive signal to the throttle motor that adjusts the position of the throttle valve, and a control signal to the ignition coil integrated with the igniter. The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 controls the operation of the engine 22 by a control signal from the HVECU 70. Further, the engine ECU 24 outputs data relating to the operating state of the engine 22 to the HVECU 70 as necessary. The engine ECU 24 calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on the crank angle θcr.

  The planetary gear 30 is configured as a single pinion type planetary gear mechanism. The sun gear of planetary gear 30 is connected to the rotor of motor MG1. The ring gear of the planetary gear 30 is connected to a drive shaft 36 that is coupled to the drive wheels 38 a and 38 b via a differential gear 37. A crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30.

  The motor MG1 is configured as a well-known synchronous generator motor including a rotor in which permanent magnets are embedded and a stator in which a three-phase coil is wound, and the rotor is connected to the sun gear of the planetary gear 30 as described above. Has been. The motor MG2 is configured as a synchronous generator motor similar to the motor MG1, and the rotor is connected to the drive shaft 36. Motors MG1 and MG2 are connected to inverters 41 and 42 via bus bar unit 60, and are driven by controlling inverters 41 and 42 by motor electronic control unit (hereinafter referred to as "motor ECU") 40. The inverters 41 and 42 are connected to a power line 54 to which the battery 50 is connected. The inverters 41 and 42 are configured as well-known inverters including six transistors and six diodes. Since the inverters 41 and 42 share the power line 54, the power generated by either the motor MG1 or MG2 can be supplied to another motor.

  FIG. 2 is a configuration diagram schematically showing an outline of the configuration of the bus bar unit 60. Bus bar unit 60 is connected to a three-phase coil of motor MG1 and connected to a three-phase coil of motor MG2 while being connected to a three-phase coil of motor MG2 and bus bars 61u, 61v and 61w connected to a three-phase power line of inverter 41. Bus bars 62u, 62v, 62w connected to the phase power line. The bus bars 61u, 61v, 61w and the bus bars 62u, 62v, 62w are arranged so as to be arranged at equal intervals in this order as shown in the figure. The bus bar unit 60 also includes phase current sensors 65u, 65v, 65w, 66u, 66v that detect the phase currents Iu1, Iv1, Iw1, Iu2, Iv2, Iw2 flowing through the bus bars 61u, 61v, 61w, 62u, 62v, 62w. 66w. In FIG. 2, the up and down bidirectional arrows shown on the bus bars 62u, 62v and 62w indicate that a phase current flows, and the up and down bidirectional arrows on the bus bars 61u, 61v and 61w. What is not done indicates that no phase current is flowing.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . Signals from various sensors necessary for driving and controlling the motors MG1, MG2 are input to the motor ECU 40 via the input port. The signals from the various sensors include, for example, rotational positions θm1, θm2 from a rotational position detection sensor (not shown) that detects the rotational positions of the rotors of the motors MG1, MG2, and bus bars 61u, 61v, 61w, 62u, 62v, 62w. Phase current sensors Iu1, Iv1, Iw1, Iw2, Iv2, Iv2, Iw2 from the phase current sensors 65u, 65v, 65w, 66u, 66v, 66w attached to the capacitor 46, a capacitor from a voltage sensor (not shown) attached between the terminals of the capacitor 46 The voltage VL of 46 (power line 54) can be mentioned. From the motor ECU 40, switching control signals to the transistors of the inverters 41 and 42 for driving and controlling the motors MG1 and MG2 are output via the output port. The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40 controls driving of the motors MG1 and MG2 by a control signal from the HVECU 70. In addition, motor ECU 40 outputs data relating to the driving state of motors MG1 and MG2 to HVECU 70 as necessary. The motor ECU 40 calculates the rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2.

  The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydride secondary battery, and exchanges electric power with the motors MG1 and MG2 via the inverters 41 and 42. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52.

  Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . A signal necessary for managing the battery 50 is input to the battery ECU 52 via the input port, and data regarding the state of the battery 50 is transmitted to the HVECU 70 by communication as necessary. As a signal input via the input port, for example, the voltage Vb between terminals from a voltage sensor (not shown) installed between the terminals of the battery 50 or the power line 54 connected to the output terminal of the battery 50 is attached. Examples thereof include a charge / discharge current Ib from a current sensor (not shown), a battery temperature Tb from a temperature sensor (not shown) attached to the battery 50, and the like. Further, the battery ECU 52 calculates the storage ratio SOC and input / output limits Win and Wout in order to manage the battery 50. The storage ratio SOC is a ratio of the capacity of electric power that can be discharged from the battery 50 to the total capacity, and is calculated based on the integrated value of the charge / discharge current Ib detected by the current sensor. The input / output limits Win and Wout are the maximum allowable power that may charge and discharge the battery 50, and are calculated based on the calculated storage ratio SOC and the battery temperature Tb.

  Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. Signals from various sensors are input to the HVECU 70 via input ports. Examples of the signals from the various sensors include an ignition signal from the ignition switch 80 and a shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81. Further, the accelerator opening Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, and the vehicle speed sensor 88 The vehicle speed V can also be mentioned. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port. The HVECU 70 exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52.

  The hybrid vehicle 20 of the embodiment configured in this way is in a hybrid travel mode (HV travel mode) that travels with the operation of the engine 22 or in an electric travel mode (EV travel mode) that travels while the operation of the engine 22 is stopped. Run.

  Here, motors MG1 and MG2, inverters 41 and 42, a bus bar unit 60, and a motor ECU 40 correspond to the driving device of the embodiment.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation when the inverter 41 is shut down so as not to drive the motor MG1 when traveling in the EV traveling mode will be described. FIG. 3 shows an example of a shutdown control routine executed by the motor ECU 40 when the inverter 41 is shut down. This routine is repeatedly executed at predetermined time intervals (for example, every several milliseconds) when the inverter 41 is to be shut down.

  When the shutdown control routine is executed, the motor ECU 40 firstly selects the bus bar 62u connected to the motor MG2 among the phase current sensors 65u, 65v, 65w attached to the bus bars 61u, 61v, 61w connected to the motor MG1. , 62v, 62w is selected (step S100). The bus bars 61u, 61v, 61w, 62u, 62v, 62w are arranged in this order from the left as shown in FIG. Since the motor MG2 is driven, phase currents Iu2, Iv2, and Iw2 flow through the three-phase coil of the motor MG2. When a current flows through the bus bars 62u, 62v, 62w, a magnetic field is formed in the vicinity of the bus bars 62u, 62v, 62w. Therefore, the magnetic field is affected by the magnetic field in the vicinity of the bus bars 62u, 62v, 62w. Since the influence of the magnetic field becomes smaller as the distance increases, the bus bar 61u is least affected by the bus bars 61u, 61v, 61w. Step S100 is a process of selecting a phase current sensor (phase current sensor 65u in the embodiment) attached to the bus bar that is not affected most.

  Subsequently, the phase current Iu1 from the selected phase current sensor 65u is set as the determination phase current Is (step S110), and it is determined whether or not the absolute value of the determination phase current Is exceeds the threshold value Iref (step S110). S120). Since the inverter 41 is shut down, the phase of the three-phase coil of the motor MG1 is increased when the rotation speed Nm1 of the motor MG1 increases and the back electromotive voltage of the motor MG1 becomes larger than the voltage acting on the inverters 41 and 42. Current flows. The threshold value Iref is for detecting that a phase current has flowed through the three-phase coil of the motor MG1 in a state where the inverter 41 is shut down, and a value slightly larger than 0 can be used. When it is determined that the absolute value of the determination phase current Is does not exceed the threshold value Iref, it is determined that the back electromotive voltage of the motor MG1 is equal to or lower than the voltage acting on the inverters 41 and 42, and the inverter 41 continues to shut down. (Step S130), and this routine is finished.

  When it is determined in step S120 that the absolute value of the determination phase current Is exceeds the threshold value Iref, the shutdown of the inverter 41 is canceled (step S140), and control is performed so that no current flows through the three-phase coil of the motor MG1. (Zero current control) is executed (step S150), and this routine is terminated.

  FIG. 4 is an explanatory diagram illustrating an example of a change over time in the rotational speed Nm1 of the motor MG1, the phase currents Iu1 and Iw1, the state of the inverter 41, and whether or not zero current control is performed. Since the phase current Iu1 flowing in the bus bar 61u for the motor MG1 is away from the bus bars 62u, 62v, 62w for the motor MG2, the phase current Iu1 is hardly affected by the magnetic field due to the current flowing in the bus bars 62u, 62v, 62w. Therefore, the phase current Iu1 is stably zero until the time N1 when the rotation speed Nm1 of the motor MG1 increases and the phase current exceeds the threshold value Iref in the three-phase coil of the motor MG1. On the other hand, since the bus bar 61w disposed adjacent to the bus bar 62u is easily affected by the magnetic field due to the current flowing through the bus bars 62u, 62v, 62w, the phase current Iw1 flowing through the bus bar 61w becomes unstable, and the rotational speed Nm1 of the motor MG1. In some cases, the threshold value Iref is exceeded even though the value is small. For this reason, if the phase current Iw1 detects that a current has flowed through the three-phase coil of the motor MG1, a false detection occurs, and unnecessary shutdown of the inverter 41 is canceled and unnecessary zero current control is executed. At time T1 when the phase current Iu1 exceeds the threshold value Iref, the shutdown of the inverter 41 is released and zero current control is executed. For this reason, no current flows through the three-phase coil of the motor MG1.

  In the driving apparatus mounted on the hybrid vehicle 20 of the embodiment described above, the bus bars 61u, 61v, 61w connected to the three-phase coil of the motor MG1 and the bus bars 62u, 62v, 62w connected to the three-phase coil of the motor MG2. Are arranged in this order. When the inverter 41 is shut down because the motor MG1 is not driven, the magnetic field generated by the current flowing in the bus bars 62u, 62v, 62w for the motor MG2 being driven out of the bus bars 61u, 61v, 61w for the motor MG1. The phase current sensor 65u attached to the bus bar 61u that is least affected is selected, and when the phase current Iu1 detected by the phase current sensor 65u exceeds the threshold value Iref, the shutdown of the inverter 41 is canceled, and zero current control is performed. Run. Thus, by selecting the phase current sensor 65u attached to the bus bar 61u that is least affected by the magnetic field due to the current flowing through the bus bars 62u, 62v, 62w, the motor MG1 connected to the inverter 41 that is shut down is selected. False detection of the flowing current can be suppressed.

  The drive device mounted on the hybrid vehicle 20 of the embodiment includes two motors MG1, MG2, two inverters 41, 42, and two sets of bus bars 61u, 61v, 61w, 62u, 62v, 62w. However, it may be provided with three or more motors, three or more inverters, and three or more sets of bus bars. For example, like the drive device mounted on the hybrid vehicle 120 illustrated in FIG. 5, the motor MGR attached to the wheels 39a and 39b via the differential gear 37b and the motor MGR are added to the configuration of the drive device of the embodiment. The inverter 43 to be driven and the bus bar unit 160 may be provided. In this case, as shown in FIGS. 6 and 7, the bus bar unit 160 includes bus bars 63u, 63v, 63w connected to the three-phase coil of the motor MGR, and bus bars 61u, 61v, 61v connected to the three-phase coil of the motor MG1. 61w, bus bars 62u, 62v, 62w connected to the three-phase coil of the motor MG2 are arranged in this order. Further, phase current sensors 67u, 67v, 67w for detecting the phase currents Iur, Ivr, Iwr are attached to the bus bars 63u, 63v, 63w for the motor MGR. Similarly to the embodiment, the phase bar sensors 61u, 61v, 61w for the motor MG1 and the bus bars 62u, 62v, 62w for the motor MG2 detect the phase currents Iu1, Iv1, Iw1, Iu2, Iv2, Iw2. 65u, 65v, 65w, 66u, 66v, 66w are attached. In FIG. 6, the inverter 41 for the motor MG1 is shut down by indicating the up and down bidirectional arrows on the bus bars 62u, 62v, 62w for the motor MG2 and the bus bars 63u, 63v, 63w for the motor MGR. This shows a state where the inverter 42 for the motor and the inverter 43 for the motor MGR are driven. In FIG. 7, only the bus bars 62u, 62v, and 62w for the motor MG2 are shown with a double arrow in the vertical direction, and the inverter 41 for the motor MG1 and the inverter 43 for the motor MGR are shut down, and the motor MG2 The state where the inverter 42 is driven is shown.

  The driving apparatus for the hybrid vehicle 120 of this modification can also execute the shutdown control routine shown in FIG. In step S100, as a phase current sensor that is most unaffected by the other motor bus bars 61u, 61v, 61w for the motor MG1, in the state of FIG. 6, in the state of FIG. 6, the inverter 42 for the motor MG2 and the motor MGR Since the inverter 43 is driven, the phase current sensor 65v attached to the bus bar 61v farthest from the bus bars 62u, 62v, 62w for the motor MG2 and the bus bars 63u, 63v, 63w for the motor MGR is selected. On the other hand, in the state of FIG. 7, since the inverter 43 for the motor MGR is shut down, the phase current sensor 61u attached to the bus bar 65u farthest from the bus bars 62u, 62v, 62w for the motor MG2 is selected.

  Further, in the driving apparatus for the hybrid vehicle 120 according to the modification, the shutdown time control routine of FIG. 3 can be applied when the inverter 43 for the motor MGR is shut down. In this case, in step S100, among the motor MGR bus bars 63u, 63v, 63w, as phase current sensors that are most unaffected by the other motor bus bars, the motor MG1 bus bars 61u, 61v, 61w and the motor MG2 are used. The phase current sensor 67u attached to the bus bar 63u farthest from the bus bars 62u, 62v, 62w is selected.

  In the driving device mounted on the hybrid vehicle 20 or 120 of the embodiment or the modification, the phase current sensor attached to the bus bar farthest from the bus bar for the other motor being driven is selected. The phase current sensor attached to the bus bar not adjacent to the bus bar for the other motor being driven may be selected. For example, in the state of FIG. 2, the phase current sensor attached to any of the bus bars 61u, 61v that are not adjacent to the bus bars 62u, 62v, 62w for the motor MG2 being driven may be selected. In the state of FIG. 7, if applied when the inverter 41 for the motor MG1 is shut down, it is applied to any of the bus bars 61u, 61v that are not adjacent to the bus bars 62u, 62v, 62w for the motor MG2 that is being driven. An attached phase current sensor is selected. If applied when the motor MGR inverter 43 is shut down in the state of FIG. 7, the motor MGR1 inverter 41 is also shut down, so that the motor MGR bus bar 63u, 63v, 63w An attached phase current sensor is selected.

  In the driving devices mounted on the hybrid vehicles 20 and 120 according to the embodiments and the modified examples, the bus bars are arranged in one row, but may be arranged in two or more rows. Absent.

  In the drive device of the embodiment or the modified example, the engine 22, the planetary gear 30, the two motors MG <b> 1, MG <b> 2 and the drive shaft 36 coupled to the drive wheels 38 a, 38 b are mounted on a hybrid vehicle. However, as long as it is a hybrid vehicle having two or more motors, it may be mounted on a hybrid vehicle having any configuration. Moreover, as long as it has two or more motors, it is good also as what is mounted in the electric vehicle which is not equipped with an engine. Furthermore, it is good also as what is mounted in moving bodies other than a motor vehicle, and good also as what is integrated in the installation which does not move.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of drive devices.

  20, 120 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 30 planetary gear, 36 drive shaft, 37, 37b differential gear, 38a, 38b drive wheel, 39a, 39b wheel, 40 motor Electronic control unit (motor ECU), 41, 42, 43 inverter, 46 capacitor, 50 battery, 52 battery electronic control unit (battery ECU), 54 power line, 60, 160 busbar unit, 61u, 61v, 61w, 62u 62v, 62w, 63u, 63v, 63w Bus bar, 65u, 65v, 65w, 66u, 66v, 66w, 67u, 67v, 67w Phase current sensor, 70 Hybrid electronic control unit (HV ECU), 0 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 an accelerator pedal position sensor, 85 brake pedal, 86 a brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2, MGR motor.

Claims (1)

A plurality of motors driven by three-phase AC power;
A plurality of inverters for driving the plurality of motors;
A plurality of three-phase bus bars connecting the plurality of motors and the plurality of inverters;
A control device for controlling the plurality of inverters;
A drive device comprising:
The plurality of three-phase bus bars are arranged side by side,
When the control device shuts down any one of the plurality of inverters, the control device is connected to an inverter that is not shut down among the three-phase bus bars of the motor that is connected to the shut down inverter. Release the shutdown of the inverter that is shut down when the current flowing in the bus bar of the phase that is not adjacent to the three-phase bus bar of the motor exceeds the threshold,
A drive device characterized by that.

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