JP4128891B2 - Motor control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a motor control device that controls an AC motor such as a permanent magnet motor, a reluctance motor, or an induction motor.
[0002]
[Prior art]
Conventionally, in order to control the output torque of this type of AC motor with high accuracy, current feedback control on the orthogonal coordinate dq axis that rotates in synchronization with the motor rotating magnetic flux is generally performed (Patent Literature). 1).
[0003]
Also, in current feedback control on the dq axis, in order to prevent a vibration phenomenon due to mutual interference between the d axis current control system and the q axis current control system, and to improve current response performance against a sudden change in current command value, The interference compensation voltage is calculated and added to the dq axis voltage.
[0004]
An example of a motor control device that performs such control will be described with reference to FIG.
[0005]
In FIG. 3, the motor control device includes a d-axis current controller 1, a q-axis current controller 2, and a non-interference controller 3 having a non-interference compensation voltage calculation unit 34.
[0006]
The d-axis current controller 1 obtains and outputs a d-axis voltage command VdPI with the d-axis current command IdRef and the d-axis current Id as inputs.
[0007]
The q-axis current controller 2 receives the q-axis current command IqRef and the q-axis current Iq and obtains and outputs a q-axis voltage command VqPI.
[0008]
The non-interacting compensation voltage calculator 34 receives the d-axis current IdRef, the q-axis current IqRef, and the rotation angular frequency ω as inputs and obtains and outputs the d-axis compensation voltage VdFF and the q-axis compensation voltage VqFF by the following calculation. To do.
[0009]
VdFF = −ω × Lq × IqRef
VqFF = ω × (Ld × IdRef + ΦPM)
(Ld: motor d-axis inductance, Lq: motor q-axis inductance, ΦPM: permanent magnet magnetic flux)
The non-interacting compensation voltage calculator 34 calculates a pre-applied voltage based on the d-axis and q-axis current commands, the motor d-axis, the q-axis inductance, and the permanent magnet magnetic flux, and adds it to the dq-axis voltage to compensate. By doing so, the current control system is stabilized.
[0010]
[Patent Document 1]
Japanese Patent Publication No. 3-1917 [0011]
[Problems to be solved by the invention]
Although it is theoretically desirable to calculate the non-interacting compensation voltage using the actual current value, the control may become unstable due to a noise component or the like included in the current feedback value. On the other hand, the vibration phenomenon due to dq mutual interference is suppressed by high-speed control of the d-axis current controller and the q-axis current controller, and in order to further improve the responsiveness to the current command value sudden change, Instead, the decoupling compensation voltage is calculated using the current command value, and the calculated value may be used.
[0012]
However, due to the high performance of permanent magnet motors and the like, in recent years, high-speed rotating motors exceeding 10,000 rpm have been developed for electric vehicles, hybrid cars, and the like. When the motor rotation speed increases and the dq axis rotation angular frequency ω increases, the vibration frequency of the vibration phenomenon due to dq mutual interference also increases in proportion to ω, and therefore cannot be suppressed by the control response speed of the dq axis current controller. May end up.
[0013]
An object of the present invention is to provide a motor control device that realizes stable control in all speed bands.
[0014]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a d-axis current that calculates a d-axis voltage command so that a detected d-axis current value follows a d-axis current command value on a rotating coordinate axis dq that rotates at an angular frequency ω. A controller;
A q-axis current controller that calculates a q-axis voltage command so that the q-axis current detection value follows the q-axis current command value on the rotational coordinate axis dq axis;
In a motor control device comprising a non-interference controller that calculates a dq-axis mutual interference voltage component and adds it to a d-axis voltage command and a q-axis voltage command,
The non-interference controller calculates a q-axis non-interference component voltage from a weighted average value of a d-axis current command and a detected d-axis current value according to a preset distribution ratio, and calculates a q-axis current command according to a preset distribution ratio. And d-axis non-interference component voltage is calculated from a weighted average value of the q-axis current detection value.
[0015]
In order to solve the above problem, the present invention calculates the d-axis voltage command so that the d-axis current detection value follows the d-axis current command value on the rotation coordinate axis dq rotating at the angular frequency ω. An axis current controller, a q-axis current controller that calculates a q-axis voltage command so that the q-axis current detection value follows the q-axis current command value on the rotational coordinate axis dq axis, and a dq-axis mutual interference voltage component A non-interference controller that calculates and adds to the d-axis voltage command and the q-axis voltage command, and outputs a one-pulse waveform that turns on and off once in one cycle in synchronization with the inverter frequency. In a phase control type motor control device that performs current control by operating an on / off switching phase of the one-pulse waveform with respect to a rotor,
The non-interference controller calculates a q-axis voltage command value for determining an on / off switching phase of the one-pulse waveform from a value obtained by weighted averaging a d-axis current command and a d-axis current detection value according to a preset distribution ratio. A non-interacting voltage compensator that calculates and calculates a d-axis voltage command value from a weighted average value of the q-axis current command and the q-axis current detection value according to a preset distribution ratio; The on / off switching phase of the one-pulse waveform is manipulated by taking the result value of the detector.
[0016]
According to the present invention having the above-described configuration, stable control is realized in all speed bands by using a value obtained by adding and averaging the current feedback value and the current command value with a preset weight for the calculation of the decoupling compensation voltage. Is done.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment: corresponding to claims 1 and 2)
The motor control device of this embodiment will be described with reference to FIG.
[0018]
The motor control device in the first embodiment includes a d-axis current controller 1, a q-axis current controller 2, and a non-interference controller 30.
[0019]
Further, the non-interference controller 30 includes a weighting factor setting unit 31, a weighting factor multiplication unit d32, a weighting factor multiplication unit q33, and a non-interference compensation voltage calculation unit 34.
[0020]
The d-axis current controller 1 receives the d-axis current command IdRef and the d-axis current Id as input and obtains and outputs the d-axis voltage command VdPI by the following calculation.
[0021]
VdPI = G (s) · (IdRef−Id)
(G (s) is a control gain, s is a Laplace operator, and proportional / integral control can be considered)
The q-axis current controller 2 receives the q-axis current command IqRef and the q-axis current Iq and obtains and outputs the q-axis voltage command VqPI by the following calculation.
[0022]
VqPI = G (s) · (IqRef−Iq)
(G (s) is a control gain, s is a Laplace operator, and proportional / integral control can be considered)
The weighting coefficient setting unit 31 receives the rotation angular frequency ω as an input and obtains and outputs the weighting coefficient COG by the following calculation.
[0023]
COG = | ω | / ωMax
(ΩMax is the electrical angular frequency at maximum motor rotation)
The weighting factor multiplier d32 receives the d-axis current command IdRef, the d-axis current Id, and the weighting factor COG output from the weighting factor setting unit 31, and obtains and outputs the non-interfering d-axis current IdFF by the following calculation. To do.
[0024]
IdFF = COG × Id + (1−COG) × IdRef
The weighting factor multiplication unit q33 receives the q-axis current command IqRef, the q-axis current Iq, and the weighting factor COG output from the weighting factor setting unit 31, and obtains and outputs the non-interfering q-axis current IqFF by the following calculation. To do.
[0025]
IqFF = COG × Iq + (1-COG) × IqRef
In the non-interacting compensation voltage calculator 34, the non-interfering d-axis current IdFF output from the weighting factor multiplier d32, the non-interfering q-axis current IqFF output from the weighting factor multiplier q33, and the rotation angular frequency ω To obtain the d-axis compensation voltage VdFF and the q-axis compensation voltage VqFF by the following calculation and output them.
[0026]
VdFF = −ω × Lq × IqFF
VqFF = ω × (Ld × IdFF + ΦPM)
(Ld: motor d-axis inductance, Lq: motor q-axis inductance, ΦPM: permanent magnet magnetic flux)
The non-interference controller 3 finally has the d-axis compensation voltage VdFF and q-axis compensation voltage VqFF output from the non-interacting compensation voltage calculator 34, and the d-axis voltage command VdPI output from the d-axis current controller 1. And the q-axis voltage command VqPI output from the q-axis current controller 2, and the d-axis voltage Vd and the q-axis voltage Vq are obtained and output by the following calculation.
[0027]
Vd = VdPI + VdFF
Vq = VqPI + VqFF
As described above, according to the motor control apparatus of the present embodiment, the d-axis voltage Vd is output from the non-interacting compensation voltage calculation unit 34 to the d-axis voltage command VdPI output from the d-axis current controller 1. The d-axis compensation voltage VdFF is added to the q-axis voltage Vq, and the q-axis voltage command VqPI output from the q-axis current controller 2 is added to the q-axis voltage command VqPI. Since the value obtained by adding the axis compensation voltage VqFF, a stable current control system can be configured in all speed bands from low speed to high speed.
[0028]
(Second embodiment: corresponding to claims 3, 4 and 5)
The motor control device of this embodiment will be described with reference to FIG.
[0029]
The motor control device in the second embodiment includes a d-axis current controller 1, a q-axis current controller 2, a weighting factor setting unit 31, a weighting factor multiplication unit d32, a weighting factor multiplication unit q33, and non-interference. The compensation voltage calculation unit 34, the q-axis current controller 4, the polar coordinate conversion unit 5, and the voltage vector calculation unit 6 are configured.
[0030]
The d-axis current controller 1 receives the d-axis current command IdRef and the d-axis current Id as input and obtains and outputs a d-axis voltage command VdP by the following calculation.
[0031]
VdP = Kp · (IdRef−Id)
(Kp is proportional gain)
The q-axis current controller 2 receives the q-axis current command IqRef and the q-axis current Iq as inputs and obtains and outputs the q-axis voltage command VqP by the following calculation.
[0032]
VqP = Kp · (IqRef−Iq)
(Kp is proportional gain)
The weighting coefficient setting unit 31 receives the rotation angular frequency ω as an input and obtains and outputs the weighting coefficient COG by the following calculation.
[0033]
COG = | ω | / ωMax
(ΩMax is the electrical angular frequency at maximum motor rotation)
The weighting factor multiplier d32 receives the d-axis current command IdRef, the d-axis current Id, and the weighting factor COG output from the weighting factor setting unit 31, and obtains and outputs the non-interfering d-axis current IdFF by the following calculation. To do.
[0034]
IdFF = COG × Id + (1−COG) × IdRef
The weighting factor multiplication unit q33 receives the q-axis current command IqRef, the q-axis current Iq, and the weighting factor COG output from the weighting factor setting unit 31, and obtains and outputs the non-interfering q-axis current IqFF by the following calculation. To do.
[0035]
IqFF = COG × Iq + (1-COG) × IqRef
In the non-interacting compensation voltage calculator 34, the non-interfering d-axis current IdFF output from the weighting factor multiplier d32, the non-interfering q-axis current IqFF output from the weighting factor multiplier q33, the rotation angular frequency ω, To obtain the d-axis compensation voltage VdFF and the q-axis compensation voltage VqFF by the following calculation and output them.
[0036]
VdFF = −ω × Lq × IqFF
VqFF = ω × (Ld × IdFF + ΦPM)
(Ld: motor d-axis inductance, Lq: motor q-axis inductance, ΦPM: permanent magnet magnetic flux)
The torque current control unit 4 receives the q-axis current command IqRef and the q-axis current Iq, and obtains and outputs the voltage vector phase correction value γ2 by the following calculation so that the q-axis current follows the q-axis current command.
[0037]
γ2 = G (s) × (IqRef−Iq)
(G (s) is a control gain. S is a Laplace operator. Proportional integral control can be considered.)
The above is an example in the case of a surface magnet type permanent magnet motor, and is an arithmetic expression when the current contributing to the torque is the q-axis direction current. However, in different types of motors such as a reluctance motor, the current contributing to the torque However, in this case, the input may be changed so that the current in the direction contributing to the torque follows the command value.
[0038]
In the polar coordinate conversion unit 5, the d-axis compensation voltage VdFF and the q-axis compensation voltage VqFF output from the non-interacting compensation voltage calculation unit 34, the d-axis voltage command VdP output from the d-axis current controller 1, q The d-axis voltage Vd ′ calculated from the q-axis voltage command VqP output from the shaft current controller 2 and the q-axis voltage Vq ′ are input, and the voltage vector amplitude V1 and the voltage vector phase γ are obtained and output. .
[0039]
Vd '= VdP + VdFF
Vq ′ = VqP + VqFF
V1 = √6 / π × Vdc
(Vdc is the inverter input DC voltage)
γ = tan−1 (Vq ′ / Vd ′)
In the voltage vector calculation unit 6, the voltage vector amplitude V 1 output from the polar coordinate conversion unit 5, the voltage vector phase γ, and the voltage vector phase correction value γ 2 output from the torque current control unit 4 are input. To obtain and output the d-axis voltage command Vd and the q-axis voltage command Vq.
[0040]
Vd = V1 × cos (γ + γ2)
Vq = V1 × sin (γ + γ2)
The motor control device having the above configuration outputs a so-called one-pulse waveform that is turned on / off once in one cycle in synchronization with the inverter frequency, and manipulates the on / off switching phase of the one-pulse waveform for the motor rotor. Thus, a stable current control system can be configured even when high-speed rotation operation is performed by phase control that performs current control.
[0041]
【The invention's effect】
As described above, according to the present invention, stable control is realized in all speed bands by using a value obtained by adding and averaging the current feedback value and the current command value with a preset weighting for the calculation of the decoupling compensation voltage. It is possible to provide a motor control device that can do this.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a first embodiment of a motor control device according to the present invention.
FIG. 2 is a diagram showing a configuration of a second embodiment of a motor control device according to the present invention.
FIG. 3 is a diagram showing a configuration of a conventional motor control device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... d-axis current controller, 2 ... q-axis current controller, 3 ... Non-interference controller, 31 ... Weight coefficient setting part, 32 ... Weight coefficient multiplication part d, 33 ... Weight coefficient multiplication part q, 34 ... Non-interference Compensation voltage calculator, 4... Q-axis current controller, 5... Polar coordinate converter, 6.

Claims (5)

A d-axis current controller for calculating a d-axis voltage command so that the d-axis current detection value follows the d-axis current command value on the rotation coordinate axis dq axis rotating at the angular frequency ω;
A q-axis current controller that calculates a q-axis voltage command so that the q-axis current detection value follows the q-axis current command value on the rotational coordinate axis dq axis;
In a motor control device comprising a non-interference controller that calculates a dq-axis mutual interference voltage component and adds it to a d-axis voltage command and a q-axis voltage command,
The non-interference controller calculates a q-axis non-interference component voltage from a weighted average value of a d-axis current command and a detected d-axis current value according to a preset distribution ratio, and calculates a q-axis current command according to a preset distribution ratio. And d-axis non-interference component voltage is calculated from a value obtained by weighted averaging the q-axis current detection value. 2. The motor control apparatus according to claim 1, wherein a distribution ratio used for weighted average of the current command value and the current detection value is variable depending on the motor rotation angular frequency ω. A d-axis current controller for calculating a d-axis voltage command so that the d-axis current detection value follows the d-axis current command value on the rotation coordinate axis dq axis rotating at the angular frequency ω;
A q-axis current controller that calculates a q-axis voltage command so that the q-axis current detection value follows the q-axis current command value on the rotational coordinate axis dq axis;
a non-interference controller that calculates a dq-axis mutual interference voltage component and adds it to the d-axis voltage command and the q-axis voltage command;
A phase control type that outputs a one-pulse waveform that turns on and off once in a cycle in synchronization with the inverter frequency, and controls the current by operating the on-off switching phase of the one-pulse waveform for the rotor of the AC motor. In the motor control device,
The non-interference controller calculates a q-axis voltage command value for determining an on / off switching phase of the one-pulse waveform from a value obtained by weighted averaging a d-axis current command and a d-axis current detection value according to a preset distribution ratio. A non-interacting voltage compensator that calculates and calculates a d-axis voltage command value from a weighted average value of the q-axis current command and the q-axis current detection value according to a preset distribution ratio; A motor control apparatus that takes in the result value of the controller and operates the on / off switching phase of the one-pulse waveform. 4. The motor control device according to claim 3, further comprising a voltage phase corrector for manipulating a voltage vector phase obtained from the dq axis voltage command so that the motor torque component current matches the torque component current command value. A motor control device. 4. The motor control device according to claim 3, wherein the distribution ratio used for the weighted average of the current command value and the current detection value is variable depending on the motor rotation angular frequency ω.

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