JP5060393B2 - Inverter control device - Google Patents

Description

  The present invention relates to an inverter control device that drives a synchronous motor.

  In the field of railway vehicles, a configuration in which a DC power source and an inverter device are connected via a power reception filter including a reactor and a capacitor, and an AC motor is driven by converting DC power into AC power is widely used. In this case, an unstable phenomenon occurs due to resonance between the reactor and the capacitor. On the other hand, for example, Patent Document 1 discloses a technique for suppressing the unstable phenomenon of the power reception filter.

In Patent Document 1, in an inverter control device that drives an induction motor, a voltage command in a magnetic flux direction of the induction motor, a voltage command in a direction orthogonal to the magnetic flux direction, and a slip frequency command are manipulated to control the power reception filter. Suppress instability phenomenon.
JP 2002-238298 A Takayoshi Nakano Vector control of AC motors Nikkan Kogyo Shimbun

  For example, when the induction motor is replaced with a synchronous motor for the purpose of increasing the efficiency of the motor, the technique of Patent Document 1 cannot be used because the synchronous motor does not have a slip frequency. Therefore, when driving a synchronous motor, a technique for suppressing the unstable phenomenon of the power receiving filter without operating the frequency command is required.

  The objective of this invention is suppressing the instability phenomenon of a receiving filter in the inverter control apparatus which drives a synchronous motor.

An inverter control device according to the present invention includes a DC power source, an inverter device, a power receiving filter connected between the DC power source and the inverter device, at least one synchronous motor driven by the inverter device, A means for generating a voltage command for the inverter device; a means for obtaining an electric quantity on the DC side of the inverter device; the means for generating the voltage command includes a motor constant and a command value for the current in the magnetic flux direction; Means for generating a first voltage command for the inverter device based on a command value for a current orthogonal to the magnetic flux direction, a motor constant, a current in the magnetic flux direction, a command value for the current in the magnetic flux direction, and Based on the current value orthogonal to the magnetic flux direction and the command value for the current orthogonal to the magnetic flux direction, A means for generating a second voltage command, and a first voltage command, and generates a voltage command to said inverter based on said second voltage command.

Further, the means for suppressing the AC component includes a command value for the current in the magnetic flux direction input to the means for generating the first voltage command and the magnetic flux direction input to the means for generating the first voltage command. A command value for the current in the magnetic flux direction input to the means for generating the second voltage command and a means for generating the second voltage command. it is intended to manipulate the axial torque of the synchronous motor by operating at least one of the command value to the orthogonal to that current in the flux direction to enter.

  ADVANTAGE OF THE INVENTION According to this invention, the instability phenomenon of a receiving filter can be suppressed in the inverter control apparatus which drives a synchronous motor.

  Embodiments of the present invention will be described below with reference to the drawings.

  A first embodiment of the inverter control apparatus according to the present invention will be described with reference to FIGS. FIG. 1 shows the principle of operation of the present invention. In FIG. 1A, an inverter device 3 is connected to a DC power source 1 through a power receiving filter 2 including a reactor 5 and a capacitor 6, and converts DC power into three-phase AC power. The synchronous motor 4 receives the three-phase AC power output from the inverter device 3 as an input, converts it into shaft torque, and outputs it.

  As described above, the unstable phenomenon of the power receiving filter 2 occurs due to resonance between the reactor 5 and the capacitor 6 included in the power receiving filter 2. At this time, the power on the DC side of the inverter device 3 vibrates. Therefore, by oscillating the current flowing into the inverter device 3, the AC component contained in the DC side power of the inverter device 3 is absorbed on the AC side and consumed as the power of the synchronous motor 4. Thereby, the unstable phenomenon of the power receiving filter 2 is suppressed.

The electric power Pinv on the direct current side of the inverter device 3 is expressed by Equation (1).

  Here, Pinv: DC side power of the inverter device 3, Ecf: Voltage on the DC side of the inverter device 3, Iinv: Current flowing into the inverter device 3.

Further, if the loss of the synchronous motor 4 is ignored, the electric power Pm of the synchronous motor 4 is expressed by Equation (2).

  Here, Pm: power of the synchronous motor 4, T: shaft torque of the synchronous motor 4, ωinv: frequency command, Np: number of pole pairs.

  An AC component generated in the power on the DC side of the inverter device 3 due to the unstable phenomenon of the power receiving filter 2 is denoted by ΔPinv. Further, an AC component generated in the electric power of the synchronous motor 4 in order to suppress the unstable phenomenon of the power receiving filter 2 is denoted by ΔPm.

If the inertia of the load connected to the shaft of the synchronous motor 4 is large, fluctuations in the rotational speed of the synchronous motor 4 can be ignored. Further, since the shaft torque T of the synchronous motor is expressed by the equation (3), the AC component ΔPm of the power Pm of the synchronous motor 4 and the AC component ΔT of the shaft torque T of the synchronous motor 4 and ΔT are realized. The amount of operation ΔId with respect to the current Id (hereinafter referred to as d-axis current) Id in the magnetic flux direction (hereinafter referred to as d-axis direction) of the synchronous motor 4 and the direction orthogonal to the d-axis direction for realizing ΔT (hereinafter referred to as “d”). , Q-axis direction) (hereinafter referred to as q-axis current) relation of the manipulated variable ΔIq is expressed by equation (4).

Here, T: axial torque, Ld: d-axis inductance, Lq: q-axis inductance, Ke: power generation constant, Id: d-axis current, Iq: q-axis current, Np: pole pair number.

  Here, ΔPm: AC component of Pm, ΔT: AC component of T, Np: number of pole pairs, Ld: d-axis inductance, Lq: q-axis inductance, Ke: power generation constant, Id: d-axis current, Iq: q Axis current, ΔId: operation amount for the Id, ΔIq: operation amount for the Iq, ωinv: frequency command, Np: number of pole pairs.

When the loss of the inverter device 3 and the loss of the synchronous motor 4 are ignored, the equation (5) is obtained from the equations (1) and (4).

  Where ΔPinv: AC component of the Pinv, Ecf: Voltage on the DC side of the inverter device 3, Iinv: Current flowing into the inverter device 3, ΔPm: AC component of the Pm, Ld: d-axis inductance, Lq: q-axis inductance, Ke: power generation constant, Id: d-axis current, Iq: q-axis current, ΔId: operation amount with respect to Id, ΔIq: operation amount with respect to Iq, Np: number of pole pairs.

And ΔPinv in FIG. 1 (b), and .DELTA.Pm, showing the relationship of [Delta] T. It is assumed that the AC component ΔPinv included in the power on the DC side of the inverter device 3 has increased due to the unstable phenomenon of the power receiving filter 2. In this case, the electric power of the synchronous motor 4 is increased by ΔPm by increasing the shaft torque of the synchronous motor 4 by ΔT based on the equation (5) (solid arrow in FIG. 1B).

  On the other hand, it is assumed that the AC component ΔPinv included in the power on the DC side of the inverter device 3 decreases. In this case, the electric power of the synchronous motor 4 is decreased by ΔPm by reducing the shaft torque of the synchronous motor 4 by ΔT based on the equation (5) (broken arrow in FIG. 1B).

  Thus, by operating the shaft torque of the synchronous motor 4 based on the formula (5), the AC component included in the DC side power of the inverter device 3 is absorbed in the AC side, and the synchronous motor 4 Consume as electricity. Thereby, the unstable phenomenon of the power receiving filter 2 is suppressed.

  In order to perform the ΔT operation on the shaft torque of the synchronous motor 4, the operation amount ΔId for the d-axis current and the operation amount ΔIq for the q-axis current may be derived based on the equation (5).

  FIG. 2 is a diagram showing an inverter control device to which the present invention is applied. In FIG. 2, an inverter device 3 is connected to a DC power source 1 through a power receiving filter 2 including a reactor and a capacitor, and converts DC power into three-phase AC power. The synchronous motor 4 receives the three-phase AC power output from the inverter device 3 as an input, converts it into shaft torque, and outputs it. In FIG. 1, one synchronous motor is driven, but two or more synchronous motors may be driven.

  The first adder 7 adds the first d-axis current command Id *, which is a command value for the d-axis current Id, and the d-axis current manipulated variable ΔId, which is the output of the voltage vibration suppression means 17 described later. 2 d-axis current command Id ** is output. The second adder 8 adds the first q-axis current command Iq *, which is a command value for the q-axis current Iq, and the q-axis current manipulated variable ΔIq, which is the output of the voltage vibration suppression means 17 described later. 2 q-axis current command Iq ** is output.

The vector control means 9 implements vector control which is one of the control methods for the AC motor. Since vector control is described in, for example, Non-Patent Document 1, details are omitted.
The vector control means 9 includes a first subtracter 10, a second subtractor 11, a voltage vector calculation means 12, a current control means 13, a third adder 14, and a fourth adder 15. Consists of

  The first subtracter 10 subtracts the d-axis current Id from the second d-axis current command Id ** output from the first adder 7 and outputs the result. The second subtractor 11 subtracts the q-axis current Iq from the second q-axis current command Iq ** output from the second adder 8 and outputs the result.

  The voltage vector calculation means 12 includes the second d-axis current command Id ** output from the first adder 7 and the second q-axis current command output from the second adder 8. The first d-axis voltage command Vd * and the first q-axis voltage command Vq * are output based on Iq **, the motor constant, and the frequency command ωinv for the inverter device 3 not shown here. .

  The current control means 13 is configured to output the second d-axis current Id from the first adder 7 based on the output of the first subtractor 10 and the output of the second subtractor 11. So that the q-axis current Iq follows the second q-axis current command Iq ** output from the first adder 8. The second d-axis voltage command Vd ** and the second q-axis voltage command Vq ** are output.

  The third adder 14 receives the first d-axis voltage command Vd * output from the voltage vector means 12 and the second d-axis voltage command Vd ** output from the current control means 13. The third d-axis voltage command Vd *** is output by addition. The fourth adder 15 receives the first q-axis voltage command Vq * output from the voltage vector means 12 and the second q-axis voltage command Vq ** output from the current control means 13. The third q-axis voltage command Vq *** is output by addition.

  The coordinate conversion means 16 includes the third d-axis voltage command Vd *** output from the third adder 14 and the third q-axis voltage command output from the fourth adder 15. Vq *** is subjected to coordinate transformation, and AC voltage commands Vu *, Vv *, and Vw * for the inverter device 3 are output.

  The voltage oscillation suppressing means 17 outputs the d-axis current manipulated variable ΔId and the q-axis current manipulated variable ΔIq for suppressing the AC component generated in the DC power of the inverter device 3.

  FIG. 3 shows the configuration of the voltage vibration suppressing means 17 in this embodiment. Since it is difficult to directly detect the AC component ΔPinv generated in the DC-side power of the inverter device 3, the AC component included in the DC-side voltage Ecf of the inverter device 3 detected by the voltage detection means 18 is used here. ΔEcf is used.

  The AC component extraction means 19 includes the DC side voltage Ecf of the inverter device 3 detected by the voltage detection means 18 as an input and is included in the DC side voltage Ecf of the inverter device 3 using, for example, a bandpass filter. The extracted AC component ΔEcf is extracted and output.

The current manipulated variable calculator 20 receives the AC component ΔEcf output from the AC component extractor 19 as an input, and controls the d-axis current manipulated variable ΔId based on the equation (5) so as to suppress the AC component ΔEcf. The q-axis current manipulated variable ΔIq is derived and output.

FIG. 4 shows the relationship among ΔEcf, ΔId, and ΔIq. FIG. 4 shows ΔId and ΔIq when the d-axis current Id is a negative value and the q- axis current Iq is a positive value, assuming a synchronous motor having a reverse saliency.

  In the synchronous motor having the reverse saliency, the q-axis inductance Lq is larger than the d-axis inductance Ld, and the shaft torque of the synchronous motor is increased by passing a negative d-axis current from the equation (3). Therefore, in FIG. 4, ΔId is shown with the polarity reversed so that the vertical axis direction is the direction in which the shaft torque of the synchronous motor increases.

  When ΔEcf increases, the power on the DC side of the inverter device 3 increases. Therefore, −ΔId and ΔIq are increased so that the shaft torque of the synchronous motor 4, that is, the power increases (solid line in FIG. 4). Arrow). On the other hand, when ΔEcf decreases, the power on the DC side of the inverter device 3 decreases. Therefore, −ΔId and ΔIq are decreased so that the axial torque of the synchronous motor 4, that is, the power decreases (FIG. 4). Dashed arrows).

  In this embodiment, the d-axis current manipulated variable ΔId and the q-axis current manipulated variable ΔIq output from the voltage vibration suppressing unit 17 are input to both the voltage vector calculating unit 12 and the current control unit 13. . Thereby, the interference between the voltage oscillation suppressing means 17 and the current control means 13 can be suppressed.

  Since the voltage vector calculation means 12 performs so-called feedforward control, it is possible to suppress the unstable phenomenon of the power receiving filter 2 without being affected by the response speed of the current control means 13.

  In this embodiment, since the voltage command is derived based on the d-axis current command obtained by adding the d-axis current manipulated variable ΔId and the q-axis current command obtained by adding the q-axis current manipulated variable ΔIq, the synchronous motor The optimum amplitude and phase of the voltage command can be derived in accordance with the four operating states. Therefore, the present invention can also be applied in a region where the amplitude of the output voltage of the inverter device 3 is saturated.

A second embodiment of the inverter control device of the present invention will be described with reference to FIG.
The difference from the first embodiment is that the d-axis current manipulated variable ΔId and the q-axis current manipulated variable ΔIq, which are the outputs of the voltage oscillation suppressing means 17, are input only to the voltage vector computing means 12.

  When the response speed of the current control means 13 is slower than the response speed of the voltage vibration suppression means 17 and the current control means 13 and the voltage vibration suppression means 17 do not interfere with each other, the power reception is performed with the configuration as in this embodiment. The unstable phenomenon of the filter 2 can be suppressed.

  Similarly to the first embodiment, in order to derive the voltage command based on the d-axis current command obtained by adding the d-axis current manipulated variable ΔId and the q-axis current command obtained by adding the q-axis current manipulated variable ΔIq, The optimum amplitude and phase of the voltage command can be derived in accordance with the operating state of the synchronous motor 4. Therefore, the present invention can also be applied in a region where the amplitude of the output voltage of the inverter device 3 is saturated.

A third embodiment of the inverter control apparatus of the present invention will be described with reference to FIG.
The difference from the first and second embodiments is that the d-axis current manipulated variable ΔId and the q-axis current manipulated variable ΔIq, which are the outputs of the voltage oscillation suppressing means 17, are input only to the current control means 13. Is a point.

  When the response speed of the current control means 13 is fast and can respond to the resonance frequency of the reactor and the capacitor included in the power reception filter 2, the unstable phenomenon of the power reception filter 2 can be suppressed with the configuration of the present embodiment.

  Similarly to the first and second embodiments, the voltage command is based on the d-axis current command obtained by adding the d-axis current manipulated variable ΔId and the q-axis current command obtained by adding the q-axis current manipulated variable ΔIq. Therefore, the optimum amplitude and phase of the voltage command can be derived in accordance with the operating state of the synchronous motor 4. Therefore, the present invention can also be applied in a region where the amplitude of the output voltage of the inverter device 3 is saturated.

A fourth embodiment of the inverter control device of the present invention will be described with reference to FIGS.
The difference from the first embodiment to the third embodiment is that only the q-axis current manipulated variable ΔIq is output as the output of the voltage oscillation suppressing means 17.

  As described above, the shaft torque of the synchronous motor is expressed by Expression (3). In Expression (3), the second term on the right side is proportional to the difference between the q-axis inductance Lq and the d-axis inductance Ld.

  In a synchronous motor having saliency, such as an embedded magnet type synchronous motor, since the q-axis inductance Lq and the d-axis inductance Ld are different, the second term on the right side of Equation (3) can be used. In the synchronous motor having no saliency, the q-axis inductance Lq and the d-axis inductance Ld are equal, and the second term on the right side of the equation (3) cannot be used.

  Therefore, in a synchronous motor having no saliency, the unstable phenomenon of the power receiving filter is suppressed by operating only the q-axis current Iq to vibrate the shaft torque.

In this case, the relationship between the AC component ΔPinv included in the DC-side power of the inverter device 3 and the manipulated variable ΔIq with respect to the q-axis current is obtained by setting the manipulated variable ΔId with respect to the d-axis current to zero in the formula (5). 6).

  Where ΔPinv: AC component of the Pinv, Ecf: Voltage on the DC side of the inverter device 3, Iinv: Current flowing into the inverter device 3, ΔPm: AC component of the Pm, Ld: d-axis inductance, Lq: q-axis inductance, Ke: power generation constant, Id: d-axis current, ΔIq: manipulated variable with respect to Iq, Np: number of pole pairs.

  FIG. 8 shows the configuration of the voltage vibration suppressing means 17 in this embodiment. Since it is difficult to directly detect the AC component ΔPinv generated in the DC-side power of the inverter device 3, the AC component included in the DC-side voltage Ecf of the inverter device 3 detected by the voltage detection means 18 is used here. ΔEcf is used.

  The AC component extraction means 19 includes the DC side voltage Ecf of the inverter device 3 detected by the voltage detection means 18 as an input and is included in the DC side voltage Ecf of the inverter device 3 using, for example, a bandpass filter. The extracted AC component ΔEcf is extracted and output.

  The current manipulated variable calculating means 20 receives the alternating current component ΔEcf output from the alternating current component extracting means 19 and inputs the q-axis current manipulated variable ΔIq based on equation (6) so as to suppress the alternating current component ΔEcf. Derived and output.

  In the present embodiment, the q-axis current manipulated variable ΔIq output from the voltage oscillation suppression unit 17 is input to both the voltage vector calculation unit 12 and the current control unit 13. Thereby, the interference between the voltage oscillation suppressing means 17 and the current control means 13 can be suppressed.

  Since the voltage vector calculation means 12 performs so-called feedforward control, it is possible to suppress instability due to resonance of the power receiving filter 2 without being affected by the response speed of the current control means 13.

  In this embodiment, since the voltage command is derived based on the q-axis current command obtained by adding the q-axis current manipulated variable ΔIq, the optimum amplitude and phase of the voltage command according to the operating state of the synchronous motor 4 are obtained. Can be derived. Therefore, the present invention can also be applied in a region where the amplitude of the output voltage of the inverter device 3 is saturated.

A fifth embodiment of the inverter control apparatus of the present invention will be described with reference to FIG.
The difference from the fourth embodiment is that the q-axis current manipulated variable ΔIq, which is the output of the voltage vibration suppressing means 11, is input only to the voltage vector calculating means 12.

  When the response speed of the current control means 13 is slower than the response speed of the voltage vibration vibration means 17, and the interference between the current control means 13 and the voltage vibration suppression means 17 does not occur, the configuration of this embodiment is used. The unstable phenomenon of the power receiving filter 2 can be suppressed.

  Similarly to the fourth embodiment, the voltage command is derived based on the q-axis current command obtained by adding the q-axis current manipulated variable ΔIq. Therefore, an optimum voltage command can be selected according to the operating state of the synchronous motor 4. Amplitude and phase can be derived. Therefore, the present invention can also be applied in a region where the amplitude of the output voltage of the inverter device 3 is saturated.

A sixth embodiment of the inverter control apparatus of the present invention will be described with reference to FIG.
The difference from the fourth and fifth embodiments is that the q-axis current manipulated variable ΔIq, which is the output of the voltage oscillation suppression means 17, is input only to the current control means 13.

  When the response speed of the current control means 13 is fast and can respond to the resonance frequency of the reactor and the capacitor included in the power reception filter 2, the unstable phenomenon of the power reception filter 2 can be suppressed with the configuration of the present embodiment.

  Similarly to the fourth and fifth embodiments, in order to derive a voltage command based on the q-axis current command obtained by adding the q-axis current manipulated variable ΔIq, according to the operating state of the synchronous motor 4, Optimal voltage command amplitude and phase can be derived. Therefore, the present invention can also be applied in a region where the amplitude of the output voltage of the inverter device 3 is saturated.

  In the field of railway vehicles, a method of driving an AC motor by connecting a DC power source and an inverter device through a power reception filter including a reactor and a capacitor and converting DC power to AC power is widely used. Therefore, an unstable phenomenon that occurs due to resonance between the reactor and the capacitor is an unavoidable problem.

  In the future, replacement with a synchronous motor for the purpose of improving the efficiency of the electric motor is considered to proceed, so the present invention for a synchronous motor is an important technology.

FIG. 1 is a diagram showing the operating principle of the present invention. FIG. 2 is a diagram showing a first embodiment of an inverter control apparatus to which the present invention is applied. FIG. 3 is a diagram showing the configuration of the voltage vibration suppressing means in the first embodiment of the present invention. FIG. 4 is a diagram showing the relationship among ΔEcf, ΔId, and ΔIq in the first embodiment of the present invention. FIG. 5 is a diagram showing a second embodiment of an inverter control apparatus to which the present invention is applied. FIG. 6 is a diagram showing a third embodiment of the inverter control apparatus to which the present invention is applied. FIG. 7 is a diagram showing a fourth embodiment of the inverter control apparatus to which the present invention is applied. FIG. 8 is a diagram showing the configuration of the voltage vibration suppressing means in the fourth embodiment of the present invention. FIG. 9 is a diagram showing a fifth embodiment of the inverter control apparatus to which the present invention is applied. FIG. 10 is a diagram showing a sixth embodiment of the inverter control apparatus to which the present invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 DC power supply 2 Power receiving filter 3 Inverter apparatus 4 Synchronous motor 5 Receiving filter reactor 6 Power receiving filter capacitor 7 First adder 8 Second adder 9 Vector control means 10 First subtractor 11 Second subtractor 12 voltage vector calculation means 13 current control means 14 third adder 15 fourth adder 16 coordinate conversion means 17 voltage vibration suppression means 18 voltage detection means 19 AC component extraction means 20 current manipulated variable calculation means Id * first d-axis current command Iq * first q-axis current command Id ** second d-axis current command Iq ** second q-axis current command Id d-axis current Iq q-axis current ΔId Id manipulated variable ΔIq Iq Quantity ωinv Frequency command Vd * First d-axis voltage command Vq * First q-axis voltage command Vd ** Second d-axis voltage command Vq ** Second q-axis voltage command Vd *** Third d-axis voltage command Vq *** Third q-axis voltage command Vu *, Vv *, Vw * AC voltage command Ecf Inverter unit DC side voltage ΔEcf Ecf AC component Iinv Current flowing into inverter device ΔIinv Iinv AC component T Synchronous motor shaft torque ΔT T AC component R Winding resistance Ld d-axis inductance Lq q-axis inductance Ke Power generation constant Np Number of pole pairs Pinv Inverter device DC side power ΔPinv Pinv AC component Pm Power of synchronous motor ΔPm AC component of Pm

Claims (4)

A DC power source, an inverter device, a power receiving filter connected between the DC power source and the inverter device, at least one synchronous motor driven by the inverter device, and a voltage command for the inverter device In an inverter control device having means,
The command value for the current in the magnetic flux direction of the synchronous motor and the command value for the current orthogonal to the magnetic flux direction are less based on the output of the means for obtaining the electric quantity on the DC side of the inverter device and the means for obtaining the quantity of electricity. without even have a a means for suppressing the AC component contained in the electric quantity by operating the shaft torque by operating the one said synchronous motor,
The means for generating the voltage command includes means for generating a first voltage command for the inverter device based on a motor constant, a command value for the current in the magnetic flux direction, and a command value for the current orthogonal to the magnetic flux direction. ,
Based on the motor constant, the current in the magnetic flux direction, the command value for the current in the magnetic flux direction, the current orthogonal to the magnetic flux direction, and the command value for the current orthogonal to the magnetic flux direction, Means for generating a voltage command,
An inverter control device that generates a voltage command for the inverter device based on the first voltage command and the second voltage command . The inverter control device according to claim 1,
The means for suppressing the AC component is orthogonal to the command value for the current in the magnetic flux direction input to the means for generating the first voltage command and the magnetic flux direction input to the means for generating the first voltage command. The command value for the current in the magnetic flux direction input to the means for generating the second voltage command and the means for generating the second voltage command are manipulated. inverter control apparatus characterized by operating the axial torque of the synchronous motor by operating a small transfected even one command value for current orthogonal to the flux direction. The inverter control device according to claim 1 ,
The means for suppressing the AC component is:
At least one of a command value for the current in the magnetic flux direction input to the means for generating the first voltage command and a command value for the current orthogonal to the magnetic flux direction input to the means for generating the first voltage command. An inverter control device characterized by operating the shaft torque of the synchronous motor . The inverter control device according to claim 1 ,
Said means for suppressing the AC component, perpendicular to the direction of magnetic flux entering the means for generating the command value for the flux direction of the current supplied to means for generating the second voltage command, said second voltage command inverter control apparatus characterized by operating the axial torque of the synchronous motor at least one of the command value at operation to Rukoto for current.

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