JP2005168212A - Motor control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor control device of a harmonic component-controlled type having simple circuit processing and high precision. <P>SOLUTION: A motor current is projected onto a dq-axis coordinate system rotating at a frequency of fundamental frequency components and harmonic components to obtain a projected signal (coordinate conversion signal) from circuits 18, 19. Cancel signals corresponding to the AC components of each dq-axis coordinate system are canceled from each projected signal by being subtracted with subtractors 8, 9 to extract each DC signal component. This separates the fundamental frequency components of a motor current from the harmonic components without a use of a filter. Each DC signal component is feedback-controlled so as to be converged into each command value, controlling the fundamental frequency components and the harmonic components to target values mutually independently. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a motor control device.

In order to reduce the harmonic current flowing in the AC motor, the following Patent Document 1 describes the detected current signal on the motor actual current or the primary (primary component of the fundamental current frequency) dq coordinate system rotating at the fundamental frequency. Has been proposed to reduce the harmonic current component in the actual motor current by extracting the harmonic component from the high-pass filter and controlling this harmonic signal.
JP 2002-223600

  However, the harmonic separation using the above-described filter extraction requires complicated compensation of the phase delay by the high-pass filter. In particular, when each of a plurality of harmonic currents is reduced, it is necessary to frequency-separate harmonic components on the stationary coordinate system or the primary dq axis coordinate system, and a bandpass filter or a highpass filter having steep characteristics is required. Become. Further, since the frequency of the harmonic component on the stationary coordinate system or the primary dq axis coordinate system changes depending on the rotation speed, the cutoff frequency of the bandpass filter or the high-pass filter must be adjusted according to the rotation speed. It was troublesome.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a harmonic component control type motor control device that is simple in circuit processing and high in accuracy.

  The motor control device according to claim 1, which solves the above problem, is a motor control device that feedback-controls a multiphase AC current that is passed through an armature of a multiphase AC rotating electrical machine. A multi-phase / primary dq coordinate converter for converting to a primary dq signal on a secondary dq-axis coordinate system, and at least one for converting the polyphase alternating current into a high-order dq signal on a predetermined high-order dq-axis coordinate system. A multi-phase / high-order dq coordinate conversion unit of two orders, a primary DC component extraction unit that extracts a DC component contained in the primary dq signal, and at least one that extracts a DC component contained in the high-order dq signal Higher-order DC component extraction unit, and a feedback control unit that performs feedback control to obtain deviations between the DC signal components and predetermined command values that are their target values, and to converge the deviations to 0, respectively. When It is characterized in that it comprises.

  That is, according to the present invention, the motor current is projected onto the dq axis coordinate system rotating at the frequency of the fundamental frequency component and the harmonic component to obtain the projection signal (each dq axis coordinate conversion signal), and the basic Let the frequency component and the harmonic component be the DC signal component of each projection signal (each dq axis coordinate conversion signal). Further, each DC signal component is extracted by removing the AC component of each dq axis coordinate system from each projection signal (each dq axis coordinate conversion signal). In this way, if feedback control is performed so that each DC signal component converges to its command value, the fundamental frequency component and the harmonic component can be controlled to the target value independently of each other. For the extraction of the DC component, a DC value is extracted by subtracting a command value corresponding to the AC component, or a DC component is extracted from each subsequent dq axis coordinate system signal by a low-pass filter.

  Therefore, according to the present invention, since the signal of the stationary coordinate system or the primary rotation coordinate system is not filtered, the compensation of the phase delay (different for each frequency) of the signal due to the filter passing is simplified, and a plurality of Even when controlling the harmonic current, it has a steep characteristic and does not require a band-pass filter or high-pass filter that requires a change of the pass band according to the number of revolutions. The wave current can be controlled.

  In a preferred aspect 1, the feedback control unit generates a voltage command on the dq axis coordinate system in which each deviation is 0, and outputs the voltage command on each dq axis coordinate system to the multiphase voltage of the stationary coordinate system. And adding each of the multiphase voltages for each phase to obtain an added phase voltage, and generating a phase voltage to be applied to the armature based on the added phase voltage. Thereby, the said effect can be implement | achieved more reliably.

  In a preferred aspect 2, in the aspect 1, the polyphase / higher order dq coordinate conversion unit includes a kth order dq coordinate conversion unit that converts the polyphase alternating current into a kth order dq axis coordinate system, and the primary DC component The extraction unit is a primary alternating current component of k (k is a positive integer or fraction other than 1) -primary alternating current component superimposed on the primary dq axis coordinate system current output from the primary dq coordinate conversion unit. A primary superposition alternating current component is subtracted to extract a primary dq axis direct current component, and the high order direct current component extraction unit superimposes it on the kth order dq axis coordinate system current output from the k th order dq coordinate conversion unit. a k-th order dq-axis DC component extracting unit that subtracts a k-th order superimposed AC component, which is a k-1st order AC current component, to extract a k-th order dq-axis DC component, wherein the feedback control unit is a target value 1 The primary dq-axis DC component is converged to the next dq-axis command value, and the target value Since the that the k-th order dq axis the feedback control for converging the k-th order dq axis DC component command value, the above effect of the present invention better, it can be reliably achieved.

  In a preferred aspect 3, in the above aspect 2, the feedback control unit is configured to provide a primary dq axis coordinate in which a primary dq axis deviation which is a difference between the primary dq axis command value and the primary dq axis DC component is zero. A voltage command on the system is generated, the voltage command on the primary dq-axis coordinate system is converted into a primary multiphase voltage on the stationary coordinate system, and the k-order dq-axis command value and the k-order dq-axis DC component A voltage command on the k-th order dq-axis coordinate system in which the k-th order dq-axis deviation, which is a difference from the zero, is generated, and the voltage command on the k-th order dq-axis coordinate system is used as the k-th order multiphase voltage on the stationary coordinate system. And adding the primary multiphase voltage and the kth multiphase voltage for each phase to generate an added phase voltage, and generating a phase voltage to be applied to the armature based on the added phase voltage Therefore, the above-described effects of the present invention can be realized satisfactorily and reliably.

  In a preferred aspect 4, since in the above aspect 2, the current superimposing AC component, the primary dq-axis DC component, the k-order superimposed AC component, and the k-order dq-axis DC component are generated. Good effects can be achieved reliably.

  A preferred aspect 5 is the aspect 2 in which the polyphase / higher order dq coordinate conversion unit converts the polyphase alternating current into an n (n is a positive integer or fraction larger than k) order dq axis coordinate system. A high-order direct current component extraction unit including an n-th order and nk order superimposed on the n-th order dq-axis coordinate system current output from the n-th order dq coordinate conversion unit. An n-order dq-axis DC component extraction unit that subtracts an n-order superimposed AC component, which is an AC current component, to extract an n-order dq-axis DC component, and the primary dq-axis DC component extraction unit includes the primary dq coordinate The primary dq-axis DC component is subtracted from the primary dq-axis coordinate system current output from the conversion unit by subtracting the primary superimposed AC component, which is the k-1st order and n-1st order AC current components superimposed on the current. The k-th order dq axis DC component extraction unit extracts from the k-th order dq coordinate conversion unit. The k-th order dq-axis DC component is extracted by subtracting the k-th order superimposed alternating current component, which is the k-1th order and nk-order alternating current components superimposed on the k-th order dq-axis coordinate system current, The feedback control unit converges the primary dq-axis DC component on the primary dq-axis command value, converges the k-order dq-axis DC component on the k-order dq-axis command value, and sets an n-order dq that is a target value. Since the feedback control for converging the n-th order dq-axis DC component to the axis command value is performed, the above-described effect of the present invention can be realized satisfactorily and reliably in the control of a plurality of harmonics.

  In a preferred aspect 6, in the above aspect 5, the feedback control unit is configured to provide a primary dq axis coordinate in which a primary dq axis deviation which is a difference between the primary dq axis command value and the primary dq axis DC component is zero. A voltage command on the system is generated, the voltage command on the primary dq-axis coordinate system is converted into a primary multiphase voltage on the stationary coordinate system, and the k-order dq-axis command value and the k-order dq-axis DC component A voltage command on the k-th order dq-axis coordinate system in which the k-th order dq-axis deviation, which is a difference from the zero, is generated, and the voltage command on the k-th order dq-axis coordinate system is used as the k-th order multiphase voltage on the stationary coordinate system. To generate a voltage command on the n-th order dq-axis coordinate system in which an n-th order dq-axis deviation which is a difference between the n-th order dq-axis command value and the n-th order dq-axis DC component is zero. A voltage command on the dq axis coordinate system is converted into an nth order multiphase voltage on a stationary coordinate system, and the primary multiphase voltage, the kth order multiphase voltage, and the previous An n-order multiphase voltage is added for each phase to generate an added phase voltage, and a phase voltage to be applied to the armature is generated based on the added phase voltage. Therefore, in the control of a plurality of harmonics, The above effects can be realized with good and certainty.

  In a preferred aspect 8, the current command unit for generating the primary superimposed AC component, the primary dq-axis DC component, the k-order superimposed AC component, the n-order superimposed AC component, and the n-order dq-axis DC component in the above-described aspect 6 is provided. Therefore, the above-described effects of the present invention can be realized well and reliably in controlling a plurality of harmonics.

  According to a preferred aspect 8, the primary DC component extraction unit extracts a primary dq axis DC that is a DC component of the primary dq axis coordinate system current output from the primary dq coordinate conversion unit by a low-pass filter. The component is extracted, and the high-order DC component extraction unit extracts the high-order dq-axis DC component that is the DC component from the high-order dq-axis coordinate system current output from the high-order dq coordinate conversion unit by a low-pass filter. A high-order dq-axis command value that is a target value by converging the primary dq-axis DC component to a primary dq-axis command value that is a target value. Feedback control for converging the high-order dq-axis DC component is performed.

  According to this aspect, the harmonic component (stationary coordinate system) is controlled by controlling the DC component unrelated to the rotational speed change by using the low-pass filter that does not need to change the cutoff frequency according to the rotational speed change. Therefore, it is possible to realize a harmonic control type motor control device that can simplify and improve the circuit and processing.

  In a preferred aspect 9, the k-th order dq axis command value is set to a predetermined value in order to reduce k (k is an integer of 2 or more) -1st order magnetic noise or cripple to be taken as compared with the case where the feedback control is not performed. Since it is set, k−1th order magnetic noise and torque ripple can be reduced satisfactorily, and motor operation can be performed quietly or with small torque ripple. For the technique of reducing the k-1st order magnetic noise by adjusting the kth order harmonic component, refer to the related application specification already filed by the present applicant.

  According to a preferred aspect 10, in the aspect 9, the k-th order dq-axis command value and n (in order to reduce the k-1st order and n-1st order magnetic noise or torque ripple as compared with the case where the feedback control is not performed. (n is an integer larger than k) Since the order dq axis command value is set to a predetermined value, k-1 and n-1 order vibrations and torque ripples are reduced satisfactorily and motor operation is quiet or torque ripple is small. Is possible. In addition, about the technique of reducing k-1st order and n-1st order magnetic noise by adjusting k-1st order and n-1st order harmonic components by adjusting kth order and nth order harmonic components, Please refer to the above application specification filed by the applicant.

  Hereinafter, preferred embodiments of the motor control device of the present invention will be described. Note that k and n described below are positive integers of 2 or more, and are set to, for example, 7, 13, 19 in a three-phase machine. In addition, the “direct current component” in the following description includes an alternating current component generated by, for example, changing a command value or a rotational speed in addition to a true DC component.

A first embodiment will be described with reference to a block circuit diagram shown in FIG.
(Constitution)
In FIG. 1, 1 is a current command unit, 6 to 13 are subtractors, 14 to 17 are PI amplifiers, 18 is a three-phase / first-order dq coordinate conversion unit, 19 is a three-phase / k-th order dq coordinate conversion unit, and 20 is Primary dq / 3-phase coordinate conversion unit, 21 is a k-th order dq / 3-phase coordinate conversion unit, 22-24 are adders, 25 is a PWM voltage generation circuit, 26 is a three-phase inverter, 27 and 28 detect phase currents Current sensor 29, a three-phase synchronous motor, 30 a rotation angle sensor such as a resolver for detecting the rotation angle of the three-phase synchronous motor, and 31 a rotation angle θ output from a rotation angle signal output from the rotation angle sensor 30. A position signal processing unit 32 for extracting a signal and a delay compensation calculation unit 32 for compensating for a phase delay of the rotation angle θ.

  The current command unit 1 includes a primary current command unit and a k-th order current command unit. The primary current command unit includes a primary dq-axis coordinate system current command unit 2 and a k-th order dq-axis coordinate system current. The command unit 3 is included. The k-order current command unit includes a primary dq-axis coordinate system current command unit 4 and a k-order dq-axis coordinate system current command unit 5.

A part or all of each circuit part except the PWM voltage generation circuit 25, the three-phase inverter 26, the current sensors 27 and 28, the three-phase synchronous motor 29, and the rotation angle sensor 30 should be realized by software arithmetic processing in addition to the dedicated circuit. You can also.
(Description of operation)
The following description will be made assuming that only the primary current and the k-order current flow through the motor 29. As is clear from FIG. 1, the U-phase current iu and the V-phase current iv detected by the current sensors 27 and 28 are the three-phase / first-order dq coordinate conversion unit 18 and the three-phase / k-th order dq coordinate conversion unit. 19 and sent to.

  First, the control of the primary current will be described.

  The three-phase / first-order dq coordinate conversion unit 18 converts the input current coordinate system from a stationary coordinate system to a primary dq coordinate system that is a dq-axis coordinate system rotating at a fundamental frequency, and the d-axis current id1 and the q-axis A current iq1 is obtained. Accordingly, the d-axis current id1 and the q-axis current iq1 are respectively a DC component (primary dq-axis coordinate system) corresponding to the fundamental frequency component (static coordinate system) of the motor current and a k-order frequency component (static) of the motor current. K-1 order component (primary dq axis coordinate system) corresponding to (coordinate system).

  The d-axis current id1 and the q-axis current iq1 are sent to the subtracters 8 and 9, and the subtractors 8 and 9 subtract the current command values idk1 * and iqk1 * from the d-axis current id1 and the q-axis current iq1. The current command values idk1 * and iqk1 * are command values having a (k−1) th order frequency as shown in Equation 1, and are substantially equal to the alternating current component (k−1 primary component) of id1 and iq1. For this reason, the output waveforms of the subtracters 8 and 9 are DC components (corresponding to the primary current components of the primary dq axis coordinate system and the stationary coordinate system) from which the k-order current component (static coordinate system) is roughly removed.

  The subtracters 6 and 7 obtain the DC component (primary dq axis coordinate system) of the motor current output from the subtractors 8 and 9 from the current command values id11 * and iq11 *, that is, the primary current component (static coordinate system). Subtraction is performed to obtain primary current deviations Δid1 and Δiq1. The current command values id11 * and iq11 * are target values at which the primary current component (static coordinate system) of the motor current should converge.

  The PI amplifiers 14 and 15 calculate the primary voltage commands Vd1 and Vq1 so that the primary current deviations Δid1 and Δiq1 are 0, and the calculated primary voltage commands Vd1 and Vq1 are the primary dq / 3-phase AC coordinates. After the coordinate conversion is performed to the primary (stationary coordinate system) three-phase voltage commands Vu1, Vv1, and Vw1 by the conversion unit 20, the adders 22, 23, and 24 describe the k-order (stationary coordinate system) three-phase voltage described later. The addition result is added to the command value, and the addition results of the adders 22, 23, 24 are converted into PWM voltage by the PWM voltage generation circuit 25 to drive the three-phase inverter 26. The primary current supplied to the motor 29 is controlled to the current command values id11 * and iq11 *.

  Next, control of the k-order current will be described.

  The three-phase / k-th order dq coordinate conversion unit 19 converts the coordinate system of the input current (iu, iv) from the stationary coordinate system to the k-th order dq coordinate system that is the dq-axis coordinate system of the k-th harmonic frequency, and d-axis A current idk and a q-axis current iqk are obtained. The d-axis current idk and the q-axis current iqk are respectively a DC component (k-th order dq coordinate system) corresponding to a k-th order frequency component (stationary coordinate system) of the motor current and a fundamental frequency DC component (stationary coordinate system) of the motor current. ) -Order component (k-th order dq coordinate system).

  The d-axis current idk and the q-axis current iqk are sent to the subtracters 10 and 11, and the subtracters 10 and 11 subtract the current command values id1k * and iq1k * from the d-axis current idk and the q-axis current iqk. The current command values id1k * and iq1k * are command values having a (k−1) th order frequency as shown in Equation 2, and are substantially equal to the alternating current component (k−primary component) of idk and iqk. For this reason, the output waveforms of the subtracters 10 and 11 are DC components (corresponding to k-order current components in the k-order dq-axis coordinate system and the stationary coordinate system) from which the primary current component (stationary coordinate system) is roughly removed.

  The subtractors 12 and 13 obtain the DC component (k-th order dq axis coordinate system) of the motor current output from the subtracters 12 and 13 from the current command values idkk * and iqkk *, that is, the k-th order current component (stationary coordinate system). Subtraction is performed to obtain k-order current deviations Δidk and Δiqk. The current command values idkk * and iqkk * are target values that the k-th order current component (static coordinate system) of the motor current should converge.

  The PI amplifiers 16 and 17 calculate k-order voltage commands Vdk and Vqk so that these k-order current deviations Δidk and Δiqk are 0, and the calculated k-order voltage commands Vdk and Vqk are k-order dq / 3-phase AC coordinates. After the coordinate conversion is performed to the k-order (stationary coordinate system) three-phase voltage command Vuk, Vvk, Vwk by the conversion unit 21, the above-described primary (stationary coordinate system) three-phase voltage is added by the adders 22, 23, 24. As described above, the addition result of the adders 22, 23, and 24 is converted into a PWM voltage by the PWM voltage generation circuit 25 to drive the three-phase inverter 26. Thereby, the k-th order current fed from the three-phase inverter 26 to the three-phase synchronous motor 29 is controlled to the current command values idkk * and iqkk *.

  Next, the current command unit 1 will be described. As described above, the current command unit 1 generates four pairs of command values.

  The primary dq axis coordinate system current command unit 2 outputs primary current command values id11 * and iq11 * to which the primary current of the motor current should converge. The primary current command values id11 * and iq11 * are calculated using a map or the like based on the torque target value and the rotational speed as is well known, but are values on the primary dq axis coordinate system. Therefore, it becomes a direct current value.

The k-th order dq-axis coordinate system current command unit 5 outputs k-th order current command values idkk * and iqkk * at which the k-th order current command value of the motor current should converge. The k-order current command values idkk * and iqkk * are calculated by, for example, an arithmetic unit (not shown) to reduce the k-1st order magnetic noise and the k-1st order torque ripple. Since it is the above value, it becomes a DC value.
The k-th order dq-axis coordinate system current command unit 3, when the motor actual current is k-th order dq-axis converted, is superimposed on the k-th order current (a DC component on the k-th order dq-axis coordinate system). Current command values id1k * and iq1k * for canceling (primary component on the stationary coordinate system) are output. This calculation may be performed using Equation 2, or the primary current command values id11 * and iq11 *, which are direct current values on the primary dq axis coordinate system, are converted from the primary dq coordinate system to the k-1 dq axis coordinate system. It may be obtained by converting to. Further, these calculations may be regarded as functions such as a torque command, a motor rotation speed, an inverter voltage, etc., and obtained from a map or the like.

  The primary dq-axis coordinate system current command unit 4 is a k−1 primary AC component that is superimposed on the primary current (DC component on the primary dq-axis coordinate system) when the motor actual current is converted into the primary dq axis. Current command values idk1 * and iqk1 * for canceling (the kth order component on the stationary coordinate system) are output. This calculation may be performed using Equation 1, or k-order current command values idkk * and iqkk *, which are direct current values on the k-th order dq-axis coordinate system, from the k-th order dq coordinate system to the k-1 dq-axis coordinate system. It may be obtained by converting to. Further, these calculations may be regarded as functions such as a torque command, a motor rotation speed, an inverter voltage, etc., and obtained from a map or the like.

The primary dq coordinate conversion unit 18 and the k-th order dq coordinate conversion unit 19 perform coordinate conversion from the stationary coordinate system to the rotation coordinate system with reference to the rotation angle θ. Of course, θ is calculated in the k-th order dq coordinate conversion unit 19 so as to correspond to kθ. The delay compensation unit 32 compensates for the phase delay caused by the above-described control being calculated by a microcomputer or the like.
(Modification)
In the above embodiment, the case where one type of harmonic current is superimposed or superimposed on the motor current has been described, but the same circuit block as the circuit block used for k-th order (static coordinate system) current component control in FIG. 1 is added. As a matter of course, other harmonic current components can be controlled.

A second embodiment for simultaneously controlling the k-order component and the n-order component of the motor current will be described with reference to the block circuit diagram shown in FIG. Hereinafter, n is a positive integer larger than k.
(Constitution)
2, a circuit having the same reference numeral as that in FIG. 1 has the same function as that in FIG. 1, and therefore description thereof is omitted. Only a circuit portion added to FIG. 1 in FIG. The additional circuit includes subtracters 10 ′, 11 ′, 12 ′, 13 ′ and adders 22 ′, 23 ′, 24 ′, 80, 90, 100, 101, 100 ′, in addition to a current command unit 1 described later. 101 ′, a three-phase / n-order dq coordinate conversion unit 19 ′, an n-order dq / three-phase coordinate conversion unit 21 ′, and PI amplifiers 16 ′ and 17 ′. In addition to the current command units 2 to 5 described in the first embodiment, the current command unit 1 includes current command units 3 ′, 4 ′, and 31 to 33 described later.

  The k-th order dq-axis coordinate system current command unit 3 ′, when the motor actual current is k-th order dq-axis converted, is superimposed on the k-th order current (DC component on the k-th order dq-axis coordinate system). Current command values idnk * and iqnk * for canceling the component (n-order component on the stationary coordinate system) are output.

  The primary dq axis coordinate system current command unit 4 ′, when the motor actual current is converted to the primary dq axis, is superimposed on the motor primary current (DC component on the primary dq axis coordinate system). Current command values idn1 * and iqn1 * for canceling the AC component (n-order component on the stationary coordinate system) are output. This calculation can be performed in the same manner as the current command values idk1 * and iqk1 *.

  The n-order dq-axis coordinate system current command unit 31 outputs n-order current command values idnn * and iqnn * where the n-order current command value of the motor current should converge. The n-order current command values idnn * and iqnn * are calculated by, for example, an arithmetic unit (not shown) to reduce the n-1st order magnetic noise and the n-1st order torque ripple. Since it is the above value, it becomes a DC value.

  The n-order dq axis coordinate system current command unit 32 superimposes the n-order AC component superimposed on the n-order current (DC component on the n-order dq axis coordinate system) when the motor actual current is converted to the n-order dq-axis. Current command values id1n * and iq1n * for canceling (primary component on the stationary coordinate system) are output.

The n-th order dq-axis coordinate system current command unit 33, when the motor actual current is converted to the n-th order dq-axis, is superimposed on the n-th order current (DC component on the n-th order dq-axis coordinate system). Current command values idkn * and iqkn * for canceling (the k-th order component on the stationary coordinate system) are output.
(Description of operation)
The following description will be made assuming that the motor 29 can be regarded as only the primary current, the k-order current, and the n-order current.

  As is apparent from FIG. 2, the U-phase current iu and the V-phase current iv detected by the current sensors 27 and 28 are the three-phase / first-order dq coordinate conversion unit 18 and the three-phase / k-th order dq coordinate conversion unit. 19 and the three-phase / n-th order dq coordinate conversion unit 19 ′.

  First, the control of the primary current will be described.

  The three-phase / first-order dq coordinate conversion unit 18 converts the input current coordinate system from a stationary coordinate system to a primary dq coordinate system that is a dq-axis coordinate system rotating at a fundamental frequency, and the d-axis current id1 and the q-axis A current iq1 is obtained. The d-axis current id1 and the q-axis current iq1 each have a direct current component, a k−1 order component, and an n−1 order component. These d-axis current id1 and q-axis current iq1 are sent to the subtracters 8 and 9.

The adder 80 adds the current command value idk1 * and the current command value idn1 *, the adder 90 adds the current command value iqk1 * and the current command value iqn1 *, and the subtractors 8 and 9 are the d-axis current id1. And the current command values idk1 * + idn1 * and iqk1 * + iqn1 * are subtracted from the q-axis current iq1.
The current command values idk1 * + idn1 * and iqk1 * + iqn1 * are substantially equal to the sum of the k−1 order AC component and the n−1 order AC component of id1 and iq1, and therefore the output waveforms of the subtractors 8 and 9 Is a direct current component (primary dq axis coordinate system) from which k-th and n-th order current components (static coordinate system) are roughly removed.

  The subtracters 6 and 7 obtain the direct current component (primary dq axis coordinate system) of the motor current output from the subtractors 8 and 9 from the current command values id11 * and iq11 *, that is, the primary current component (static coordinate system). Subtraction is performed to obtain primary current deviations Δid1 and Δiq1. The current command values id11 * and iq11 * are target values at which the primary current component (static coordinate system) of the motor current should converge. The following control is the same as in the first embodiment.

  Next, control of the k-order current will be described.

  The three-phase / k-th order dq coordinate conversion unit 19 converts the coordinate system of the input current (iu, iv) from the stationary coordinate system to the k-th order dq coordinate system that is the dq-axis coordinate system of the k-th harmonic frequency, and d-axis A current idk and a q-axis current iqk are obtained. The d-axis current idk and the q-axis current iqk are respectively a DC component (k-th order dq coordinate system) corresponding to a k-th order frequency component (stationary coordinate system) of the motor current and a fundamental frequency DC component (stationary coordinate system) of the motor current. ) -Order component (k-order dq coordinate system) corresponding to the motor current) and nk-order component (k-order dq coordinate system) corresponding to the n-order component (static coordinate system) of the motor current. These d-axis current idk and q-axis current iqk are sent to the subtracters 10 and 11.

  The adder 100 adds the current command value id1k * and the current command value idnk *, the adder 101 adds the current command value iq1k * and the current command value iqnk *, and the subtractors 10 and 11 use the d-axis current idk. Current command values id1k * + idnk * and iq1k * + iqnk * are subtracted from the q-axis current iqk.

  The current command values id1k * + idnk * and iq1k * + iqnk * are substantially equal to the sum of the k−1th order AC component and the nkth order AC component of idk and iqk, and therefore the output waveforms of the subtractors 10 and 11 Is a DC component (k-th order dq-axis coordinate system) from which primary and n-th order current components (static coordinate system) are roughly removed.

  The subtractors 12 and 13 obtain the direct current component (k-th order dq axis coordinate system) of the motor current output from the subtracters 10 and 11 from the current command values idkk * and iqkk *, that is, the k-th order current component (stationary coordinate system). Subtraction is performed to obtain k-order current deviations Δidk and Δiqk. The current command values idkk * and iqkk * are target values that the k-th order current component (static coordinate system) of the motor current should converge. The following control is the same as in the first embodiment.

  Next, control of the n-order current will be described.

  The three-phase / n-order dq coordinate conversion unit 19 ′ converts the coordinate system of the input current (iu, iv) from the stationary coordinate system to the n-order dq coordinate system that is the dq-axis coordinate system of the n-th harmonic frequency, and d An axial current idn and a q-axis current iqn are obtained. The d-axis current idn and the q-axis current iqn are respectively a DC component (n-order dq coordinate system) corresponding to the n-order frequency component (static coordinate system) of the motor current and a fundamental frequency DC component (static coordinate system) of the motor current. ) -Order component (n-order dq coordinate system) and an nk-order component (n-order dq coordinate system) corresponding to the k-order component (static coordinate system) of the motor current. These d-axis current idn and q-axis current iqn are sent to subtracters 10 'and 11'.

  The adder 100 ′ adds the current command value id1n * and the current command value idkn *, the adder 101 ′ adds the current command value iq1n * and the current command value iqkn *, and the subtractors 10 ′ and 11 ′ Current command values id1n * + idkn * and iq1n * + iqkn * are subtracted from the d-axis current idn and the q-axis current iqn.

  The current command values id1n * + idkn *, iq1n * + iqkn * are substantially equal to the sum of the (n−1) th order AC component and the nk order AC component of idk, iqk, and therefore the subtracters 10 ′, 11 ′ The output waveform is a direct current component (n-order dq-axis coordinate system) from which primary and k-th order current components (static coordinate system) are roughly removed.

  The subtracters 12 ′ and 13 ′ are connected to the DC component (n-order dq axis coordinate system) of the motor current output from the subtractors 10 ′ and 11 ′ from the current command values idnn * and iqnn *, that is, the n-order current component (stationary). The coordinate system is subtracted to obtain n-order current deviations Δidn and Δiqn. The current command values idnn * and iqnn * are target values at which the n-order current component (static coordinate system) of the motor current should converge. The following control is the same as in the first embodiment.

  In the above control, an example of control of a single harmonic component and control of two harmonic components has been described. However, those skilled in the art will be able to control more harmonic components based on the same principle as described above. It is easy to understand. In each of the above embodiments, it is needless to say that addition and subtraction performed sequentially can be performed at once by one multi-input addition / subtraction process.

  In each of the above embodiments, when the torque command value changes abruptly, the primary current command values id11 * and iq11 * transiently include a high-frequency AC component.

  Therefore, when the motor rotation speed and torque command value can be considered constant, the calculated values of each phase in each dq axis coordinate system are stored for one rotation of each secondary coordinate system, and these stored values are sequentially reproduced. Therefore, the calculation can be reduced. In motor control, there are often situations in which the motor rotation speed and torque command value hardly change, so that the calculation burden and power consumption can be reduced.

In addition, when the torque command value changes suddenly, normal feedback control can be performed by interrupting the independent control of the harmonic component described above. For example, in the circuit of FIG. 1, the outputs of the current command units 3, 4, and 5 are set to 0, and the signals id 1 and iq 1 that have undergone three-phase / primary dq coordinate conversion are directly input to the subtracters 6 and 7. The output of the dq / 3-phase coordinate converter 20 is directly input to the PWM circuit 25. As a result, it is possible to speed up the follow-up of the control during a transition in which the torque command value changes suddenly.

1 is a block circuit diagram illustrating a motor control device according to a first embodiment. FIG. 6 is a block circuit diagram illustrating a motor control device according to a second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Current command part 6-13 Subtractor 14-17 PI amplifier 18 3 phase / primary dq coordinate transformation part 19 3 phase / k order dq coordinate transformation part 20 Primary dq / 3 phase coordinate transformation part 21 k order dq / 3 Phase coordinate conversion units 22 to 24 Adder 25 PWM voltage generation circuit 26 Three-phase inverters 27 and 28 Current sensor 29 Three-phase synchronous motor 30 Rotation angle sensor 31 Position signal processing unit 32 Delay compensation calculation unit

Claims (10)

In a motor control device that feedback-controls a multiphase AC current that is passed through an armature of a multiphase AC rotating electrical machine,
A three-phase / primary dq coordinate converter for converting the detected multiphase alternating current into a primary dq signal on a primary (primary component of fundamental current frequency) dq axis coordinate system;
A three-phase / high-order dq coordinate conversion unit of at least one order for converting the polyphase alternating current into a high-order dq signal on a predetermined high-order dq axis coordinate system;
A primary DC component extraction unit that extracts a DC component contained in the primary dq signal;
At least one order high-order DC component extractor for extracting a DC component contained in the high-order dq signal;
A feedback control unit that performs feedback control to obtain a deviation between each of the DC signal components and a predetermined command value that is a target value thereof, and converge each deviation to 0;
A motor control device comprising: The motor control device according to claim 1,
The feedback control unit includes:
Generate each voltage command on the dq axis coordinate system with each deviation set to 0, convert each voltage command to a multiphase voltage in the stationary coordinate system, and add each multiphase voltage for each phase and add A motor control device that generates a phase voltage to be applied to the armature based on the added phase voltage. The motor control device according to claim 1 or 2,
The three-phase / higher-order dq coordinate converter is
A k-th order dq coordinate conversion unit that converts the polyphase alternating current into a k-th order dq axis coordinate system;
The primary DC component extraction unit includes:
From the primary dq-axis coordinate system current output from the primary dq coordinate conversion unit, k is superimposed on k (k is a positive integer or fraction other than 1) -primary superimposed alternating current component which is a primary alternating current component. To extract the primary dq axis DC component,
The high-order DC component extraction unit is
The k-th order dq-axis DC component is extracted by subtracting the k-th order superimposed alternating current component that is the k-1th order alternating current component superimposed on the k-th order dq-axis coordinate system current output from the k-th order dq coordinate conversion unit. A k-th order dq-axis DC component extraction unit
The feedback control unit includes:
Feedback control is performed to converge the primary dq-axis DC component to a primary dq-axis command value that is a target value, and to converge the k-order dq-axis DC component to a k-order dq-axis command value that is a target value. A motor control device. The motor control device according to claim 3, wherein
The feedback control unit includes:
Generating a voltage command on a primary dq axis coordinate system in which a primary dq axis deviation which is a difference between the primary dq axis command value and the primary dq axis DC component is 0; The above voltage command is converted into a primary multiphase voltage on the stationary coordinate system,
Generating a voltage command on a k-th order dq-axis coordinate system in which a k-th order dq-axis deviation that is a difference between the k-th order dq-axis command value and the k-th order dq-axis DC component is 0; The above voltage command is converted into k-th order multiphase voltage on the stationary coordinate system,
The primary multiphase voltage and the kth multiphase voltage are added for each phase to generate an addition phase voltage, and a phase voltage to be applied to the armature is generated based on the addition phase voltage. Motor control device. The motor control device according to claim 3, wherein
A motor control device comprising: a current command unit that generates the primary superimposed AC component, the primary dq-axis DC component, the k-order superimposed AC component, and the k-order dq-axis DC component. The motor control device according to claim 3, wherein
The three-phase / higher-order dq coordinate conversion unit includes an n-order dq coordinate conversion unit that converts the polyphase alternating current into an n (n is a positive integer or fraction larger than k) -order dq axis coordinate system,
The high-order DC component extraction unit is an n-th order superimposition that is an n-th order and nk-order AC current component superimposed on the n-th order dq-axis coordinate system current output from the n-th order dq coordinate conversion unit. An n-order dq-axis DC component extraction unit that subtracts an AC component and extracts an n-order dq-axis DC component;
The primary dq-axis DC component extraction unit includes:
The primary superimposed alternating current component, which is the k-1 order and n-1 order alternating current components superimposed on the primary dq axis coordinate system current output from the primary dq coordinate conversion unit, is subtracted from the primary. dq axis DC component is extracted,
The k-th order dq-axis DC component extraction unit includes:
The k-th order dq is obtained by subtracting the k-th order superposed alternating current component, which is the k-1th order and nk-th order alternating current components superimposed, from the k-th order dq axis coordinate system current output from the k-th order dq coordinate conversion unit. Extract the shaft DC component,
The feedback control unit includes:
The primary dq-axis DC component is converged on the primary dq-axis command value, the k-order dq-axis DC component is converged on the k-order dq-axis command value, and the target value is the n-order dq-axis command value. A motor control device that performs feedback control to converge an n-order dq-axis DC component. The motor control device according to claim 6, wherein
The feedback control unit includes:
Generating a voltage command on a primary dq axis coordinate system in which a primary dq axis deviation which is a difference between the primary dq axis command value and the primary dq axis DC component is 0; The above voltage command is converted into a primary multiphase voltage on the stationary coordinate system,
Generating a voltage command on a k-th order dq-axis coordinate system in which a k-th order dq-axis deviation that is a difference between the k-th order dq-axis command value and the k-th order dq-axis DC component is 0; The above voltage command is converted into k-th order multiphase voltage on the stationary coordinate system,
Generating a voltage command on an n-order dq-axis coordinate system in which an n-order dq-axis deviation which is a difference between the n-order dq-axis command value and the n-order dq-axis DC component is 0; The above voltage command is converted into an nth order multiphase voltage on the stationary coordinate system,
A phase voltage applied to the armature based on the added phase voltage by adding the primary multiphase voltage, the k-th multiphase voltage, and the n-th multiphase voltage for each phase to generate an added phase voltage. A motor control device. The motor control device according to claim 6, wherein
A motor control device comprising: a current command unit that generates the primary superimposed AC component, primary dq-axis DC component, k-order superimposed AC component, n-order superimposed AC component, and n-order dq-axis DC component. The motor control device according to any one of claims 1 to 8,
The k-th order dq axis command value is set to a predetermined value in order to reduce k (k is an integer of 2 or more) minus first-order magnetic noise or torque ripple as compared with the case where the feedback control is not performed. Motor control device. The motor control device according to claim 9, wherein
Compared to the case where the feedback control is not performed, the k-th order dq-axis command value and the n-th order dq-axis command (n is an integer greater than k) in order to reduce the k-1st order and n-1st order magnetic noise or torque ripple. A motor control device characterized in that each value is set to a predetermined value.

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