JP2008005629A - Motor control unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor control unit capable of improving torque response performance in the square-wave drive of a synchronous motor. <P>SOLUTION: A current sensor 94 detects the current flowing in the synchronous motor M; an adder 11 subtracts a q-axis current value i<SB>q</SB>, from a q-axis current command value i<SB>q</SB><SP>*</SP>for generating q-axis current deviation as a correction value; a voltage command generator 13 generates a voltage vector, corrected based on the q-axis current deviation. As a result, square-wave torque control is enabled with the vector control being maintained therein, and the occurrence of torque variations at transition to the square wave drive from sinusoidal wave drive is suppressed by improving the torque response. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a motor control device, and more particularly to a motor control device that drives a synchronous motor by outputting a three-phase rectangular wave voltage from a voltage vector calculated from a command torque.

  When driving a synchronous motor using a DC power source, it is widely used to apply a pulse width modulation (PWM) waveform voltage using an inverter. However, applying the PWM waveform voltage to the synchronous motor has a limit in voltage utilization, and there is a problem that, for example, sufficient high output cannot be obtained in a high rotation range.

In order to solve such a problem, conventionally, a technique has been proposed in which a rectangular wave voltage is applied to a synchronous motor for rotational driving (see, for example, Patent Documents 1 and 2). According to this technique, it is possible to improve the output in the high rotation range.
Japanese Patent No. 3746377 Japanese Patent No. 3674741

  However, in the prior art, there is a problem that a large torque fluctuation occurs when the sine wave drive is shifted to the rectangular wave drive as the rotational speed increases, and an impact is generated.

  The present invention has been made in view of the above-described problems, and an object to be solved is to provide a motor control device capable of improving torque response performance in rectangular wave driving of a synchronous motor.

  Hereinafter, each means suitable for solving the above-described problems will be described with additional effects and the like as necessary.

1. In a motor control device that outputs a three-phase rectangular wave voltage based on a voltage vector calculated from a command torque and drives a synchronous motor,
Current detecting means for detecting a current flowing through the synchronous motor;
Correction value calculation means for calculating a correction value from the command torque and a current detected by the current detection means,
A motor control device configured to correct the voltage vector based on the correction value.

  According to the means 1, the current detecting means detects the current flowing through the synchronous motor, and the correction value calculating means calculates the correction value from the command torque and the detected current by the current detecting means, and corrects based on the correction value. Because the synchronous motor is driven by outputting a three-phase rectangular wave voltage using the voltage vector, the rectangular wave torque control can be performed while maintaining the vector control, and the torque response is improved to drive the rectangular wave from the sine wave driving. The torque fluctuation at the time of shifting to can be suppressed.

  2. The correction value calculation means calculates the correction value from a deviation between a q-axis current command value calculated from the command torque and a d-axis component of the detection current and a q-axis component of the detection current. The motor control device according to 1.

  According to the means 2, the correction value calculating means calculates the correction value from the deviation between the q-axis current command value calculated from the command torque and the d-axis component of the detected current and the q-axis component of the detected current. A suitable current can be realized.

  3. The correction value calculation means calculates the correction value from a deviation between a d-axis current command value calculated from the command torque and a q-axis component of the detection current and a d-axis component of the detection current. The motor control device according to 1.

  According to the means 3, the correction value calculating means calculates the correction value from the deviation between the d-axis current command value calculated from the command torque and the q-axis component of the detected current and the d-axis component of the detected current. A suitable current can be realized.

  4). The d-axis component of the voltage vector is corrected based on the correction value, and the q-axis component of the voltage vector is calculated based on a difference between a predetermined voltage vector magnitude and the corrected voltage vector d-axis component. The motor control device according to any one of means 1 to 3, wherein the motor control device is configured as described above.

  According to the means 4, the d-axis component of the voltage vector is corrected based on the correction value, and the q-axis component of the voltage vector is calculated based on the difference between the predetermined voltage vector magnitude and the corrected voltage vector d-axis component. Therefore, even when the voltage is limited, the torque response can be improved by the rectangular wave torque control maintaining the vector control.

  5. The q-axis component of the voltage vector is corrected based on the correction value, and the d-axis component of the voltage vector is calculated based on a difference between a predetermined voltage vector magnitude and the corrected voltage vector q-axis component. The motor control device according to any one of means 1 to 3, wherein the motor control device is configured as described above.

  According to the means 5, the q-axis component of the voltage vector is corrected based on the correction value, and the d-axis component of the voltage vector is calculated based on the difference between the predetermined voltage vector magnitude and the corrected voltage vector q-axis component. Therefore, even when the voltage is limited, the torque response can be improved by the rectangular wave torque control maintaining the vector control.

6). In a motor control device that outputs a three-phase rectangular wave voltage based on a voltage vector calculated from a command torque and drives a synchronous motor,
Torque detecting means for detecting the torque of the synchronous motor;
Voltage detection means for detecting a power supply voltage;
Limit value calculating means for calculating a voltage vector limit value from the product of a predetermined modulation factor and the power supply voltage,
The q-axis component of the voltage vector is determined from the deviation between the command torque and the detected torque, and the d-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector q-axis component. A motor control device configured as described above.

  According to the means 6, the torque detection means detects the torque of the synchronous motor, the voltage detection means detects the power supply voltage, and the limit value calculation means calculates the voltage vector limit value from the product of the predetermined modulation factor and the power supply voltage. , The q-axis component of the voltage vector is determined from the deviation between the torque command value and the detected torque, and the d-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector q-axis component, Since the synchronous motor is driven by outputting a three-phase rectangular wave voltage based on the voltage vector, the rectangular wave torque control can be performed while maintaining the vector control, and a highly accurate torque response can be realized.

7). In a motor control device that outputs a three-phase rectangular wave voltage based on a voltage vector calculated from a command torque and drives a synchronous motor,
Torque detecting means for detecting the torque of the synchronous motor;
Voltage detection means for detecting a power supply voltage;
Limit value calculating means for calculating a voltage vector limit value from the product of a predetermined modulation factor and the power supply voltage,
The d-axis component of the voltage vector is determined from the deviation between the command torque and the detected torque, and the q-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector d-axis component. A motor control device configured as described above.

  According to the means 7, the torque detecting means detects the torque of the synchronous motor, the voltage detecting means detects the power supply voltage, and the limit value calculating means calculates the voltage vector limit value from the product of the predetermined modulation factor and the power supply voltage. , The d-axis component of the voltage vector is determined from the deviation between the command torque and the detected torque, and the q-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector d-axis component, Since the synchronous motor is driven by outputting a three-phase rectangular wave voltage based on the voltage vector, the rectangular wave torque control can be performed while maintaining the vector control, and a highly accurate torque response can be realized.

8). In a motor control device that outputs a three-phase rectangular wave voltage based on a voltage vector calculated from a command torque and drives a synchronous motor,
Torque detecting means for detecting the torque of the synchronous motor;
Voltage detection means for detecting a power supply voltage;
Limit value calculation means for calculating a voltage vector limit value from the product of a predetermined modulation factor and the power supply voltage;
Current detecting means for detecting a current flowing through the synchronous motor;
With
The d-axis component of the voltage vector includes a deviation between the command torque and the detected torque, a q-axis current command value calculated from the command torque and the d-axis component of the detected current, and a q-axis component of the detected current. And a q-axis component of the voltage vector calculated from a difference between the voltage vector limit value and the voltage vector d-axis component.

  According to the means 8, the torque detecting means detects the torque of the synchronous motor, the voltage detecting means detects the power supply voltage, and the limit value calculating means calculates the voltage vector limit value from the product of the predetermined modulation factor and the power supply voltage. And the d-axis component of the voltage vector is the difference between the command torque and the detected torque, and the q-axis current command value calculated from the command torque and the d-axis component of the detected current and the q-axis component of the detected current. Since the q-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector d-axis component and the three-phase rectangular wave voltage based on the voltage vector is output to drive the synchronous motor. Torque response performance in rectangular wave torque control can be improved with a desired voltage vector magnitude.

9. In a motor control device that outputs a three-phase rectangular wave voltage from a voltage vector calculated from a command torque and drives a synchronous motor,
Torque detecting means for detecting the torque of the synchronous motor;
Voltage detection means for detecting a power supply voltage;
Limit value calculation means for calculating a voltage vector limit value from the product of a predetermined modulation factor and the detected power supply voltage;
Current detecting means for detecting a current flowing through the synchronous motor;
With
The q-axis component of the voltage vector is calculated from the voltage vector limit value, the deviation between the command torque and the detected torque, and the q-axis current command value calculated from the command torque and the d-axis component of the detected current. Calculated by subtracting the deviation of the detected current from the q-axis component, and the d-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector q-axis component. The motor control apparatus characterized by the above-mentioned.

  According to the means 9, the torque detecting means detects the torque of the synchronous motor, the voltage detecting means detects the power supply voltage, and the limit value calculating means calculates the voltage vector limit value from the product of the predetermined modulation factor and the power supply voltage. The q-axis component of the voltage vector is calculated from the voltage vector limit value, the deviation between the command torque and the detected torque, and the q-axis current command value and the detected current calculated from the command torque and the d-axis component of the detected current. The d-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector q-axis component, and the three-phase rectangular wave voltage based on the voltage vector is calculated. Since the synchronous motor is driven by outputting, the torque response performance in the rectangular wave torque control can be improved with a desired voltage vector magnitude.

  10. The voltage vector limit value is a product of a value obtained by multiplying a modulation factor of 1 or more by √ (3/8) and the detected power supply voltage, according to any one of means 6 to 9, Motor control device.

  According to the means 10, since the voltage vector limit value is a product of a value obtained by multiplying a modulation factor of 1 or more by √ (3/8) and the detected power supply voltage, the torque is controlled even if the power supply voltage fluctuates. Control responsiveness can be kept constant.

  11. When the modulation factor calculated from the ratio between the voltage vector command and the power supply voltage reaches a predetermined value of 1 or more, the sign of the three-phase AC voltage obtained by coordinate conversion of the d-axis q-axis voltage vector is positive , Vdc / 2 (Vdc is the power supply voltage) is the voltage peak value of the three-phase rectangular wave voltage, and when the sign of the three-phase AC voltage is negative, −Vdc / 2 is the voltage peak value of the three-phase rectangular wave voltage. The motor control device according to any one of means 1 to 10, wherein:

  According to the means 11, when the modulation factor calculated from the ratio between the voltage vector command and the power supply voltage reaches a predetermined value of 1 or more, the three-phase AC voltage obtained by coordinate conversion of the d-axis q-axis voltage vector is obtained. When the sign is positive, Vdc / 2 (Vdc is the power supply voltage) is the voltage peak value of the three-phase rectangular wave voltage, and when the sign of the three-phase AC voltage is negative, -Vdc / 2 is the voltage of the three-phase rectangular wave voltage. Since the peak value is set, it is possible to shift to rectangular wave control at a desired modulation rate while maintaining vector control.

  12. The voltage value ratio of the output voltage that is insufficient between the three-phase AC voltage and the three-phase rectangular wave voltage is stored in advance, and the output voltage is determined according to the modulation factor calculated from the ratio between the voltage vector command and the power supply voltage. The motor control device according to any one of means 1 to 11, wherein the motor control device is configured to complement the above.

  According to the means 12, the voltage value ratio of the output voltage that is insufficient between the three-phase AC voltage and the three-phase rectangular wave voltage is stored in advance, and the modulation factor calculated from the ratio between the voltage vector command and the power supply voltage is stored. Since the output voltage is complemented, the control command can be prevented from diverging by matching the voltage command value with the actual voltage.

  Hereinafter, embodiments embodying a motor control device of the present invention will be described with reference to the drawings.

  First, the overall configuration of the motor control device 1 of the first embodiment will be described with reference to the circuit diagram of FIG.

  The motor control device 1 is a control device for rotationally driving the synchronous motor M, and includes an Iq (q-axis current) command generation unit 10, an adder 11, a controller 12, a voltage command generation unit 13, A three-phase / two-phase converter 14, a two-phase / three-phase converter 80, a PWM signal generator 84, a PWM inverter 90, a power supply voltage detector 92, a current sensor 94, and a rotor angle detector 96 are provided. Configured.

In the motor control device 1, a command torque T ^* generated by an electronic control device (ECU) (not shown) is input to the Iq command generation unit 10 and the voltage command generation unit 13, respectively. The current sensor 94 detects the current flowing in the three phases U, V, and W of the synchronous motor M, and the detected current values i _u , i _v , and i _w of each phase U, V, and W are three-phase two. Input to the phase converter 14. The rotor angle θ of the synchronous motor M output from the rotor angle detection unit 96 is input to the three-phase / two-phase conversion unit 14 and the two-phase / three-phase conversion unit 80, respectively.

The three-phase / two-phase converter 14 converts a three-phase alternating current into a two-phase alternating current. Specifically, the three-to-two phase converter 14, three-phase current detection value i _u, i _v, i _w and the two-phase from the rotor angle theta q-axis current i _q, calculates a d-axis current i _d and the d-axis current i _d to iq command generating unit 10, respectively input to the adder 11 the q-axis current i _q.

  Here, the relationship between the UVW coordinates and the dq coordinates will be described with reference to FIG. 2A shows a coordinate diagram of fixed coordinates, and FIG. 2B shows a coordinate diagram of rotational coordinates. In FIG. 2A, UVW is a three-phase AC coordinate, and αβ is a two-phase AC coordinate. That is, the αβ coordinate is a vector composition of three-phase alternating current. In FIG. 2B, the rotor magnetic pole position is represented by θre (true value, sensor value), and the estimated rotor magnetic pole position is represented by θ ^ (estimated value). The dq coordinate is a true rotational coordinate, and the γδ coordinate is an estimated rotational coordinate.

The Iq command generation unit 10 generates a q-axis current command value i _q ^* from the command torque T ^* and the d-axis current i _d and inputs it to the adder 11. The adder 11 subtracts the q-axis current value i _q from the q-axis current command value i _q ^* to generate a q-axis current deviation, and inputs the q-axis current deviation to the voltage command generation unit 13 via the controller 12.

The voltage command generator 13 generates a d-axis component v _d ^* and a q-axis component v _q ^* of the voltage vector from the command torque T ^* and the q-axis current deviation, and inputs them to the two-phase / three-phase converter 80.

The two-phase / three-phase converter 80 converts a two-phase AC voltage into a three-phase AC voltage. Specifically, the two-phase three-phase conversion unit 80 calculates the three-phase voltage vectors v _u ^* , v _v ^* , v _w from the d-axis component v _d ^* and q-axis component v _q ^{* of the} voltage vector and the rotor angle θ. ^* Is generated and input to the PWM signal generator 80. The PWM signal generator 80 is a switching signal for generating a three-phase rectangular wave voltage based on the three-phase voltage vectors v _u ^* , v _v ^* , v _w ^* and the detected power supply voltage Vdc from the power supply voltage detector 92. Is supplied to the PWM inverter 90. In this way, the synchronous motor M is rotationally driven with a rectangular wave voltage.

FIG. 3 shows the relationship between the voltage vector v ^* , the d-axis component v _d ^*, and the q-axis component v _q ^* . It can be seen from FIG. 3 that the voltage vector v ^* can be controlled with high response from [1] to [2] by controlling v _d ^* and v _q ^* . The actual voltage limit is determined by the magnitude of the power supply voltage (v ^* _{_lim} ), and the command limit is determined by commanding the modulation factor to a predetermined value.

  Next, a description will be given of a measurement result of torque fluctuation when shifting from the sine wave drive to the rectangular wave drive as the number of rotations of the synchronous motor M increases. Here, FIG. 4A shows a voltage waveform at the time of sine wave driving, and FIG. 4B shows a voltage waveform at the time of rectangular wave driving. FIG. 5 is a graph showing measurement results of torque fluctuations when shifting from sine wave drive to rectangular wave drive. FIG. 5A is a graph of a comparative example, and FIG. 5B is a graph of an embodiment. Each is shown. The embodiment is one in which the present embodiment shown in FIG. 1 is implemented, the comparative example is one in which the prior art is implemented, and the structure of the comparative example is the Iq command generation unit 10, adders 11, 3 in FIG. 1. The configuration corresponding to the phase-to-phase conversion unit 14 and the current sensor 94 is not provided.

  In the comparative example, as shown in FIG. 5A, the detected torque fluctuates from 2 [Nm] to 3.4 [Nm] at the transition from the sine wave drive to the rectangular wave drive, and is about 1.4. It can be seen that a torque variation of [Nm] occurs. On the other hand, in the embodiment, as shown in FIG. 5B, it can be seen that there is almost no torque fluctuation at the time of transition from the sine wave drive to the rectangular wave drive.

As is clear from the above detailed description, according to the present embodiment, the current sensor 94 detects the current flowing through the synchronous motor M, and the adder 11 detects the q-axis current from the q-axis current command value i _q ^*. The value iq is subtracted to generate a q-axis current deviation as a correction value, and the voltage command generation unit 13 generates a voltage vector corrected based on the q-axis current deviation. Therefore, it is possible to perform rectangular wave torque control while maintaining vector control, improve torque response, and suppress occurrence of torque fluctuation at the time of transition from sine wave driving to rectangular wave driving.

In particular, since the correction value is calculated from the deviation between the q-axis current command value i _q ^* calculated from the command torque T ^* and the d-axis component i _{d of the} detected current and the q-axis component i _q of the detected current, the command torque T ^* An appropriate current according to the current can be realized.

In the above embodiment, the correction value is calculated from the deviation between the d-axis current command value i _d ^* calculated from the command torque T ^* and the q-axis component _iq of the detected current and the d-axis component i _d of the detected current. You may carry out by deform | transforming into.

  Next, the motor control device 2 of the second embodiment will be described with reference to the circuit diagram of FIG. In addition, the same code | symbol is attached | subjected to the component same as said 1st embodiment, and description about them is abbreviate | omitted.

  The motor control device 2 includes an Iq command generation unit 20, an adder 21, a controller 22, a Vq voltage generation unit 23, an adder 24, a Vd calculation unit 25, a three-phase to two-phase conversion unit 26, A two-phase / three-phase converter 80, a PWM signal generator 84, a PWM inverter 90, a power supply voltage detector 92, a current sensor 94, and a rotor angle detector 96 are configured.

In the motor control device 2, the command torque T ^* is input to the Iq command generation unit 20 and the Vq voltage generation unit 23, respectively. The current sensor 94 detects the current flowing in the three phases U, V, and W of the synchronous motor M, and the detected current values i _u , i _v , and i _w of each phase U, V, and W are three-phase two. Input to the phase converter 26. The rotor angle θ of the synchronous motor M output from the rotor angle detection unit 96 is input to the three-phase / two-phase conversion unit 26 and the two-phase / three-phase conversion unit 80, respectively.

The three-phase two-phase converter 26 converts a three-phase alternating current into a two-phase alternating current. Specifically, the three-to-two phase converter 26, three-phase current detection value i _u, i _v, i _w and the two-phase from the rotor angle theta q-axis current i _q, calculates a d-axis current i _d and the d-axis current i _d to iq command generating unit 20, is input to the adder 21 the q-axis current i _q.

The Iq command generation unit 20 generates a q-axis current command value i _q ^* from the command torque T ^* and the d-axis current i _d and inputs it to the adder 21. The adder 21 subtracts the q-axis current value i _q from the q-axis current command value i _q ^* to generate a q-axis current deviation, and inputs the q-axis current deviation to the adder 24 via the controller 22.

The Vq voltage generator 21 generates a voltage vector q-axis component v _q ^* and inputs it to the adder 24. Adder 24, respectively voltage vector q-axis component v _q ^* is corrected based on the q-axis current deviation, the voltage vector q-axis component v _q ^* after correction Vd calculator 25 and the two-to-three phase conversion unit 80 input. Vd calculating unit 25, a predetermined voltage vector v _m and the corrected voltage vector q-axis component v _q ^* and the voltage vector d-axis component from v _d ^*, equation ^{_{v d * = √ (v m}} 2 -v q * ² ) and input to the two-phase / three-phase converter 80.

The two-phase / three-phase converter 80 converts a two-phase AC voltage into a three-phase AC voltage. Specifically, the two-phase three-phase conversion unit 80 calculates the three-phase voltage vectors v _u ^* , v _v ^* , v _w from the d-axis component v _d ^* and q-axis component v _q ^{* of the} voltage vector and the rotor angle θ. ^* Is generated and input to the PWM signal generator 80. The PWM signal generator 80 is a switching signal for generating a three-phase rectangular wave voltage based on the three-phase voltage vectors v _u ^* , v _v ^* , v _w ^* and the detected power supply voltage Vdc from the power supply voltage detector 92. Is supplied to the PWM inverter 90. In this way, the synchronous motor M is rotationally driven with a rectangular wave voltage.

According to the present embodiment, the voltage vector q-axis component v _q ^* is corrected based on the correction value, and the voltage vector d-axis component v _d ^* is a predetermined voltage vector magnitude and the corrected voltage vector q-axis component v _q. ^Since the calculation is based on the difference from ^* , the torque response can be improved by the rectangular wave torque control that maintains the vector control even when the voltage is limited.

In the above embodiment, the voltage vector d-axis component v _d ^* is corrected based on the correction value, and the voltage vector q-axis component v _q ^* is a predetermined voltage vector magnitude and the corrected voltage vector d-axis component v _d. Modifications may be made to calculate based on the difference from ^* .

  Next, the motor control device 3 of the third embodiment will be described with reference to the circuit diagram of FIG.

  The motor control device 3 includes an adder 31, a torque control unit 32, a limit value calculation unit 33, a Vq calculation unit 34, a two-phase / three-phase conversion unit 80, a command value processing unit 82, and a PWM signal generation unit. 84, a PWM inverter 90, a power supply voltage detector 92, a rotor angle detector 96, and a torque detector 98.

Then, the command torque T ^* is input to the adder 31 and the detected torque T detected by the torque detection unit 98 is input to the adder 31. The adder 31 subtracts the detected torque T from the command torque T ^* to generate a torque deviation and inputs it to the torque control unit 32. The torque control unit 32 generates a voltage vector d-axis component v _d ^* and inputs it to the Vq calculation unit 34 and the two-phase / three-phase conversion unit 80.

On the other hand, the power supply voltage detection unit 92 detects the power supply voltage Vdc of the PWM inverter 90 and inputs it to the limit value calculation unit 33. The limit value calculation unit 33 calculates a voltage vector limit value by multiplying the product of the given predetermined modulation factor and the detected power supply voltage Vdc by √ (3/8), and inputs the voltage vector limit value to the Vq calculation unit 34. The Vq calculator 34 calculates the voltage vector q-axis component v _q ^* from the difference between the voltage vector limit value and the voltage vector d-axis component v _d ^*, and inputs the voltage vector q-axis component v _q ^* to the two-phase / three-phase converter 80.

The two-phase three-phase voltage converter 80 generates three-phase voltage vectors v _u ^* , v _v ^* , and v _w ^* from the d-axis component v _d ^* and q-axis component v _q ^{* of the} voltage vector and the rotor angle θ. To the command value processing unit 82.

  The command value processing unit 82 calculates the modulation rate from the ratio between the voltage vector command and the power supply voltage. When the modulation rate reaches a predetermined value of 1 or more, the command value processing unit 82 is obtained by coordinate conversion of the d-axis q-axis voltage vector 3 When the sign of the phase AC voltage is positive, Vdc / 2 (Vdc is the power supply voltage) is the voltage peak value of the three-phase rectangular wave voltage, and when the sign of the three-phase AC voltage is negative, −Vdc / 2 is the three-phase rectangle. The voltage peak value of the wave voltage is input to the PWM signal generator 80.

  Here, FIG. 8A is a diagram for explaining the pasting of the voltage command to the power supply voltage in the command value processing unit 82, and FIG. 8B is the waveform of the actual output voltage and the calculated output voltage of the U-phase voltage. It is a graph which shows an example.

  The PWM signal generator 80 supplies the PWM inverter 90 with a switching signal for generating a three-phase rectangular wave voltage based on the input voltage peak value. In this way, the synchronous motor M is driven with a rectangular wave voltage.

According to the present embodiment, the voltage vector d-axis component v _d ^* is determined from the deviation between the command torque T ^* and the detected torque T, and the voltage vector q-axis component v _q ^* is the voltage vector limit value and the voltage vector d. Since it is configured to be calculated from the difference from the axis component v _d ^* , it is possible to perform rectangular wave torque control while maintaining vector control and to realize a highly accurate torque response.

  Next, the motor control device 4 of the fourth embodiment will be described with reference to the circuit diagram of FIG.

  The motor control device 4 includes an adder 41, a torque controller 42, an Iq command generator 43, an adder 44, a controller 45, an adder 46, a limit value calculator 47, and a Vq calculator 48. A three-phase two-phase converter 49, a two-phase three-phase converter 80, a command value processing unit 82, a PWM signal generator 84, a PWM inverter 90, a power supply voltage detector 92, and a current sensor 94. The rotor angle detector 96 and the torque detector 98 are provided.

In the motor control device 4, the command torque T ^* is input to the adder 41 and the detected torque T detected by the torque detection unit 98 is input to the adder 41. The adder 41 subtracts the detected torque T from the command torque T ^* to generate a torque deviation and inputs it to the torque control unit 42. The torque control unit 42 generates a voltage vector d-axis component v _d ^* and inputs it to the adder 46.

On the other hand, the command torque T ^* is also input to the Iq command generation unit 43. The current sensor 94 detects currents flowing in the U phase, V phase, and W phase of the synchronous motor M, and converts the detected current values i _u , i _v , i _w of the U, V, and W phases into a three-phase to two-phase conversion unit. 49. The rotor angle of the synchronous motor M output from the rotor angle detector 96 is input to the three-phase / two-phase converter 49 and the two-phase / three-phase converter 80, respectively.

Three-to-two phase conversion unit 49, three-phase current detection value i _u, i _v, i _w and the rotor angle θ from the q-axis current i _q, and calculates a d-axis current i _d, a d-axis current i _d The q-axis current i _q is input to the adder 44 to the iq command generator 43.

The Iq command generation unit 43 generates a q-axis current command value i _q ^* from the command torque T ^* and the d-axis current value i _d and inputs it to the adder 44. The adder 44 subtracts the q-axis current value i _q from the q-axis current command value i _q ^* to generate a q-axis current deviation, and inputs the q-axis current deviation to the adder 46 via the controller 45.

The adder 46 generates a voltage vector d-axis component v _d ^* from the torque deviation and the q-axis current deviation, and inputs the voltage vector d-axis component v _d ^* to the Vq calculation unit 48 and the two-phase three-phase voltage conversion unit 80, respectively.

On the other hand, the power supply voltage detection unit 92 detects the power supply voltage Vdc of the PWM inverter 90, and the limit value calculation unit 47 multiplies the product of the predetermined modulation factor and the power supply voltage Vdc by √ (3/8) to limit the voltage vector. The value is calculated and input to the Vq calculator 48. The Vq calculator 48 calculates the q-axis component v _q ^* of the voltage vector from the difference between the voltage vector limit value and the voltage vector d-axis component v _d ^*, and inputs it to the two-phase three-phase voltage converter 80.

The two-phase three-phase voltage converter 80 generates three-phase voltage vectors v _u ^* , v _v ^* , and v _w ^* from the d-axis component v _d ^* and q-axis component v _q ^{* of the} voltage vector and the rotor angle θ. To the command value processing unit 82.

  The command value processing unit 82 calculates the modulation rate from the ratio between the voltage vector command and the power supply voltage. When the modulation rate reaches a predetermined value of 1 or more, the command value processing unit 82 is obtained by coordinate conversion of the d-axis q-axis voltage vector 3 When the sign of the phase AC voltage is positive, Vdc / 2 (Vdc is the power supply voltage) is the voltage peak value of the three-phase rectangular wave voltage, and when the sign of the three-phase AC voltage is negative, −Vdc / 2 is the three-phase rectangle. The voltage peak value of the wave voltage is input to the PWM signal generator 80.

  The PWM signal generator 80 supplies the PWM inverter 90 with a switching signal for generating a three-phase rectangular wave voltage based on the input voltage peak value. In this way, the synchronous motor M is driven with a rectangular wave voltage.

According to this embodiment, ^* the voltage vector d-axis component v _d, the command torque T ^* and the deviation between the detected torque T, and the command torque T ^* that is calculated from the d-axis component i _d of the detected current q-axis current The voltage vector q-axis component v _q ^* is determined from the difference between the voltage vector limit value and the voltage vector d-axis component v _d ^*, which is determined from the deviation between the command value i _q ^* and the detected current q-axis component i _q. Therefore, the torque response performance in the rectangular wave torque control can be improved with a desired voltage vector magnitude.

  Next, the motor control device 5 of the fifth embodiment will be described with reference to the circuit diagram of FIG.

  The motor control device 5 includes an adder 51, a torque controller 52, an Iq command generator 53, an adder 54, a controller 55, an adder 56, an adder 57, and a limit value calculator 58. Vq calculation unit 59, three-phase two-phase conversion unit 60, two-phase three-phase conversion unit 80, command value processing unit 82, PWM signal generation unit 84, PWM inverter 90, power supply voltage detection unit 92, The current sensor 94, the rotor angle detector 96, and the torque detector 98 are provided.

In the motor control device 5, the command torque T ^* is input to the adder 51 and the detected torque T detected by the torque detection unit 98 is input to the adder 51. The adder 51 generates a torque deviation by subtracting the detected torque T from the command torque T ^* and inputs the torque deviation to the torque control unit 52. The torque control unit 52 generates a voltage vector d-axis component v _d ^* and inputs it to the adder 56.

On the other hand, the command torque T ^* is also input to the Iq command generation unit 53. The current sensor 94 detects currents flowing in the U phase, V phase, and W phase of the synchronous motor M, and converts the detected current values i _u , i _v , i _w of the U, V, and W phases into a three-phase to two-phase conversion unit. Enter 60. The rotor angle of the synchronous motor M output from the rotor angle detector 96 is input to the three-phase / two-phase converter 60 and the two-phase / three-phase converter 80, respectively.

The three-phase / two-phase converter 60 calculates the q-axis current i _q and the d-axis current i _d from the detected current values i _u , i _v , i _w of the three phases and the rotor angle θ, and calculates the d-axis current i _d . The q-axis current i _q is input to the adder 54 to the iq command generator 53.

The Iq command generation unit 53 generates a q-axis current command value i _q ^* from the command torque T ^* and the d-axis current value i _d and inputs it to the adder 54. The adder 54 subtracts the q-axis current value i _q from the q-axis current command value i _q ^* to generate a q-axis current deviation and inputs the q-axis current deviation to the adder 56 via the controller 55.

The adder 56 generates a voltage vector d-axis component v _d ^* from the torque deviation and the q-axis current deviation and inputs the voltage vector d-axis component v _d ^* to the adder 57.

On the other hand, the power supply voltage detection unit 92 detects the power supply voltage Vdc of the PWM inverter 90, and the limit value calculation unit 58 multiplies the product of the predetermined modulation factor and the power supply voltage Vdc by √ (3/8) to limit the voltage vector. The value is calculated and input to the Vd calculation unit 59 and the adder 57, respectively. The adder 57 generates a voltage vector q-axis component v _q ^* from the difference between the voltage vector limit value and the output of the adder 56 and inputs the voltage vector q-axis component v _q ^* to the Vd calculation unit 59 and the two-phase three-phase voltage conversion unit 80.

The Vd calculation unit 59 calculates a voltage vector d-axis component v _d ^* from the voltage vector limit value and the voltage vector q-axis component, and inputs the voltage vector d-axis component v _d ^* to the two-phase three-phase voltage conversion unit 80.

The two-phase three-phase voltage converter 80 generates three-phase voltage vectors v _u ^* , v _v ^* , and v _w ^* from the d-axis component v _d ^* and q-axis component v _q ^{* of the} voltage vector and the rotor angle θ. To the command value processing unit 82.

  The command value processing unit 82 calculates the modulation rate from the ratio between the voltage vector command and the power supply voltage. When the modulation rate reaches a predetermined value of 1 or more, the command value processing unit 82 is obtained by coordinate conversion of the d-axis q-axis voltage vector 3 When the sign of the phase AC voltage is positive, Vdc / 2 (Vdc is the power supply voltage) is the voltage peak value of the three-phase rectangular wave voltage, and when the sign of the three-phase AC voltage is negative, −Vdc / 2 is the three-phase rectangle. The voltage peak value of the wave voltage is input to the PWM signal generator 80.

  The PWM signal generator 80 supplies the PWM inverter 90 with a switching signal for generating a three-phase rectangular wave voltage based on the input voltage peak value. In this way, the synchronous motor M is driven with a rectangular wave voltage.

According to this embodiment, ^* the voltage vector q axis component v _q, a voltage vector limit, the deviation between the command torque T ^* and the detected torque T, and a d-axis component i _d of the command torque T ^* and the detected current The voltage vector d-axis component v _d ^* is calculated by subtracting the deviation between the q-axis current command value i _q ^* calculated from the q-axis component i _q of the detected current, and the voltage vector limit value and the voltage vector q-axis Since it is configured to be calculated from the difference from the component v _q ^* , the torque response performance in the rectangular wave torque control can be improved with a desired voltage vector magnitude.

  In addition, this invention is not limited to each embodiment mentioned above, A various change is possible in the range which does not deviate from the main point of this invention.

For example, in the command value processing unit 82 in the third to fifth embodiments, the voltage value ratio of the output voltage deficient between the three-phase AC voltage and the three-phase rectangular wave voltage is stored in advance, and the voltage vector command and You may comprise so that an output voltage may be supplemented according to the modulation factor computed from ratio with a power supply voltage. For example, when the U-phase voltage is Vu ^* and the undervoltage ratio is K, the complemented output voltage Vu ^** is expressed as the equation Vu ^** = Vu ^* + K · Vu ^* , and the modulation rate Mod is It is represented by the following formula 1.

FIG. 11A is a diagram for explaining complementation by the modulation rate of the U-phase voltage Vu ^* , and FIG. 11B is a graph showing an example of the relationship between the modulation rate and the undervoltage ratio K. It is. According to this modification, it is possible to prevent control divergence by matching the voltage command value with the actual voltage.

  The present invention can be used when it is necessary to improve the torque response performance in the rectangular wave drive of the synchronous motor in the motor control device.

It is a circuit diagram showing the whole motor control device composition which is a first embodiment of the present invention. (A) is a coordinate diagram of fixed coordinates, and (b) is a coordinate diagram of rotational coordinates. It is a graph showing the relationship between the voltage vector v ^* and the d-axis component v _d ^* and the q-axis component v _q ^*. (A) is a figure which shows the voltage waveform at the time of a sine wave drive, (b) is a figure which shows the voltage waveform at the time of a rectangular wave drive. It is a graph which shows the measurement result of the torque fluctuation at the time of changing to a sine wave drive from a square wave drive, (a) shows the graph of a comparative example, (b) has shown the graph of the Example, respectively. It is a circuit diagram which shows the whole structure of the motor control apparatus which is 2nd embodiment. It is a circuit diagram which shows the whole structure of the motor control apparatus which is 3rd embodiment. (A) is a figure explaining the sticking to the power supply voltage of the voltage command in a command value process part, (b) is a graph which shows the waveform example of the actual output voltage of U phase voltage, and a calculation output voltage. It is a circuit diagram which shows the whole structure of the motor control apparatus which is 4th embodiment. It is a circuit diagram which shows the whole structure of the motor control apparatus which is 5th embodiment. (A) is a figure for demonstrating the complementation by the modulation factor of U-phase voltage, (b) is a graph which shows an example of the relationship between a modulation factor and the insufficient voltage ratio K. FIG.

Explanation of symbols

1, 2, 3, 4, 5 Motor controller 10 Iq command generator (correction value calculation means)
11 Adder (correction value calculation means)
33, 47, 58 Limit value calculation unit (limit value calculation means)
90 PWM inverter 92 Power supply voltage detection unit (voltage detection means)
94 Current sensor (current detection means)
98 Torque detection unit (torque detection means)
M Synchronous motor

Claims (12)

In a motor control device that outputs a three-phase rectangular wave voltage based on a voltage vector calculated from a command torque and drives a synchronous motor,
Current detecting means for detecting a current flowing through the synchronous motor;
Correction value calculation means for calculating a correction value from the command torque and a current detected by the current detection means,
A motor control device configured to correct the voltage vector based on the correction value.   The correction value calculation means calculates the correction value from a deviation between a q-axis current command value calculated from the command torque and a d-axis component of the detection current and a q-axis component of the detection current. Item 2. The motor control device according to Item 1.   The correction value calculating means calculates the correction value from a deviation between a d-axis current command value calculated from the command torque and a q-axis component of the detected current and a d-axis component of the detected current. Item 2. The motor control device according to Item 1.   The d-axis component of the voltage vector is corrected based on the correction value, and the q-axis component of the voltage vector is calculated based on a difference between a predetermined voltage vector magnitude and the corrected voltage vector d-axis component. 4. The motor control device according to claim 1, wherein the motor control device is configured as described above.   The q-axis component of the voltage vector is corrected based on the correction value, and the d-axis component of the voltage vector is calculated based on a difference between a predetermined voltage vector magnitude and the corrected voltage vector q-axis component. 4. The motor control device according to claim 1, wherein the motor control device is configured as described above. In a motor control device that outputs a three-phase rectangular wave voltage based on a voltage vector calculated from a command torque and drives a synchronous motor,
Torque detecting means for detecting the torque of the synchronous motor;
Voltage detection means for detecting a power supply voltage;
Limit value calculating means for calculating a voltage vector limit value from the product of a predetermined modulation factor and the power supply voltage,
The q-axis component of the voltage vector is determined from the deviation between the command torque and the detected torque, and the d-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector q-axis component. A motor control device configured as described above. In a motor control device that outputs a three-phase rectangular wave voltage based on a voltage vector calculated from a command torque and drives a synchronous motor,
Torque detecting means for detecting the torque of the synchronous motor;
Voltage detection means for detecting a power supply voltage;
Limit value calculating means for calculating a voltage vector limit value from the product of a predetermined modulation factor and the power supply voltage,
The d-axis component of the voltage vector is determined from the deviation between the command torque and the detected torque, and the q-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector d-axis component. A motor control device configured as described above. In a motor control device that outputs a three-phase rectangular wave voltage based on a voltage vector calculated from a command torque and drives a synchronous motor,
Torque detecting means for detecting the torque of the synchronous motor;
Voltage detection means for detecting a power supply voltage;
Limit value calculation means for calculating a voltage vector limit value from the product of a predetermined modulation factor and the power supply voltage;
Current detecting means for detecting a current flowing through the synchronous motor;
With
The d-axis component of the voltage vector includes a deviation between the command torque and the detected torque, a q-axis current command value calculated from the command torque and the d-axis component of the detected current, and a q-axis component of the detected current. And a q-axis component of the voltage vector calculated from a difference between the voltage vector limit value and the voltage vector d-axis component. In a motor control device that outputs a three-phase rectangular wave voltage from a voltage vector calculated from a command torque and drives a synchronous motor,
Torque detecting means for detecting the torque of the synchronous motor;
Voltage detection means for detecting a power supply voltage;
Limit value calculation means for calculating a voltage vector limit value from the product of a predetermined modulation factor and the detected power supply voltage;
Current detecting means for detecting a current flowing through the synchronous motor;
With
The q-axis component of the voltage vector is calculated from the voltage vector limit value, the deviation between the command torque and the detected torque, and the q-axis current command value calculated from the command torque and the d-axis component of the detected current. Calculated by subtracting the deviation of the detected current from the q-axis component, and the d-axis component of the voltage vector is calculated from the difference between the voltage vector limit value and the voltage vector q-axis component. The motor control apparatus characterized by the above-mentioned.   10. The voltage vector limit value is a product of a value obtained by multiplying a modulation factor of 1 or more by √ (3/8) and the detected power supply voltage. The motor control apparatus described.   When the modulation factor calculated from the ratio between the voltage vector command and the power supply voltage reaches a predetermined value of 1 or more, the sign of the three-phase AC voltage obtained by coordinate conversion of the d-axis / q-axis voltage vector is positive. When Vdc / 2 (Vdc is a power supply voltage) is a voltage peak value of the three-phase rectangular wave voltage, and the sign of the three-phase AC voltage is negative, -Vdc / 2 is a voltage wave of the three-phase rectangular wave voltage. The motor control device according to claim 1, wherein the motor control device has a high value.   The voltage value ratio of the output voltage that is insufficient between the three-phase AC voltage and the three-phase rectangular wave voltage is stored in advance, and the output voltage is supplemented according to the modulation rate calculated from the ratio between the voltage vector command and the power supply voltage. The motor control device according to claim 1, wherein the motor control device is configured as described above.

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