JP2022068658A - Control device for motor - Google Patents

Abstract

To suppress torque ripple which cannot be suppressed in a case where switching of sensor-using control and sensorless control is determined only by using a rotation speed of a motor, in a control device for controlling drive of the motor by using the rotation speed of the motor calculated from a current flowing to the motor or the rotation speed of the motor calculated from a position of a rotor.SOLUTION: A control device 1 comprises: a first calculation unit 71 for calculating a rotation speed ω1 from a current Iq flowing to a motor M; a second calculation unit 72 for calculating a rotation speed ω2 from a position θ of a rotor; a third calculation unit 73 for calculating a rotation speed ω3 from a weight w1 in a case where the rotation speed ω3 is reflected with the rotation speed ω1 and the rotation speed ω2, and from the rotation speed ω1 and the rotation speed ω2; and a command value output unit for outputting voltage command values Vd* and Vq* on the basis of a rotation speed difference Δω between the rotation speed ω3 and a rotation speed command value ω*. The third calculation unit 73 calculates the weight w1 from at least one amplitude value among an amplitude value Aω of pulsation included in the rotation speed ω2, an amplitude value Ai of pulsation included in the current Iq, and an amplitude value Av of pulsation included in the voltage command value Vq*.SELECTED DRAWING: Figure 1

Description

The present invention relates to a motor control device.

As a motor control device, when the motor rotation speed is smaller than the threshold value, the motor drive is controlled (sensor use control) using the motor rotation speed calculated from the position of the rotor detected by the sensor, and the motor rotation is performed. When the number is equal to or greater than the threshold value, there is a motor that controls the drive of the motor (sensorless control) by using the rotation speed calculated by the current flowing through the motor. According to this control device, it is possible to suppress an increase in the amplitude value of the pulsation (high frequency component) included in the rotation speed of the motor due to the influence of the quantization error included in the position of the rotor at the time of high rotation of the motor. , It is possible to suppress an increase in the amplitude value of the pulsation included in the current flowing through the motor and the voltage command value, and it is possible to suppress the torque ripple. Patent Document 1 is a related technique.

However, in the above control device, when the rotation speed of the motor is smaller than the threshold value even though the amplitude value of the pulsation included in the rotation speed of the motor is relatively large, the rotation speed calculated by the current flowing through the motor is calculated. Is used to control the drive of the motor, so that it is not possible to suppress an increase in the amplitude value of the pulsation included in the current flowing in the motor or the voltage command value, and there is a possibility that the torque ripple cannot be suppressed.

Japanese Unexamined Patent Publication No. 2007-16971

An object according to one aspect of the present invention is the rotation of a motor in a control device that controls the drive of the motor by using the rotation speed of the motor calculated by the current flowing through the motor and the rotation speed of the motor calculated by the position of the rotor. It is to suppress torque ripple that cannot be suppressed when switching between sensor use control and sensorless control is determined using only the number.

The motor control device according to the present invention has a first calculation unit that calculates the first rotation speed of the motor based on the current flowing through the motor, and a rotor position of the motor. A second calculation unit that calculates the number of rotations of 2, a first weight that is a ratio of the first rotation number and the second rotation number to be reflected in the third rotation number, and the first rotation. The voltage command value is output based on the number and the third calculation unit that calculates the third rotation speed from the second rotation speed, and the rotation speed difference between the third rotation speed and the rotation speed command value. The command value output unit, the drive circuit that outputs the drive signal according to the comparison result between the voltage value of the carrier and the voltage command value, and the DC input that is input by turning the switching element on and off by the drive signal. The third calculation unit includes an inverter circuit that converts electric power into AC electric power to drive the motor, and the third calculation unit is a pulsation amplitude value included in the second rotation speed and a pulsation included in the current flowing through the motor. The first weight is obtained from at least one amplitude value of the amplitude value and the amplitude value of the pulsation included in the voltage command value.

As a result, when at least one amplitude value of the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value is relatively large. Since the first weight can be obtained so that the first rotation speed, which is not affected by the quantization error included in the rotor position, becomes the third rotation speed, the quantization error included in the rotor position can be obtained. The drive of the motor can be controlled by using the third rotation speed which is not affected by. Therefore, it is possible to suppress the amplitude value of the pulsation included in the current flowing through the motor and the voltage command value, and it cannot be suppressed when switching between sensor use control and sensorless control is determined using only the rotation speed of the motor. Torque ripple can be suppressed.

Further, the control device has at least one of a pulsation amplitude value included in the second rotation speed, a pulsation amplitude value included in the current flowing through the motor, and a pulsation amplitude value included in the voltage command value. A storage unit for storing information indicating the correspondence between the amplitude value and the first weight is provided, and the third calculation unit refers to the information and refers to the pulsation included in the second rotation speed. Even if it is configured to obtain the first weight corresponding to at least one amplitude value of the amplitude value, the amplitude value of the pulsation included in the current flowing through the motor, and the amplitude value of the pulsation included in the voltage command value. good.

As a result, when the first weight is obtained, the load of the calculation process on the third calculation unit can be reduced.

Further, the third calculation unit is of the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value. The first weight is obtained by PI control so that at least one amplitude value becomes a target amplitude value which is the at least one amplitude value when the amplitude value of the torque ripple of the motor is equal to or less than the allowable value. It may be configured in.

As a result, it is not necessary to prepare information indicating the correspondence between the pulsation amplitude value and the first weight in advance, and the man-hours for calculating the weight can be reduced.

Further, the third calculation unit is of the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value. The second weight is obtained from at least one amplitude value, the third weight is obtained from the second rotation speed, and the product of the second weight and the third weight is taken as the first weight. It may be configured to do so.

As a result, when at least one amplitude value of the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value is relatively large. In addition, when the second rotation speed is relatively large, that is, there is a high possibility that the pulsation amplitude value is relatively large due to the influence of the quantization error included in the position of the rotor, and the motor When the number of revolutions is relatively large, the first weight can be obtained so that the first number of revolutions, which is not affected by the quantization error included in the position of the rotor, becomes the third number of revolutions. It is possible to control the drive of the motor by using the third rotation speed that is not affected by the quantization error included in the position, and it is possible to suppress the amplitude value of the pulsation included in the current flowing in the motor and the voltage command value. The torque ripple of the motor can be suppressed.

Further, the control device includes a storage unit for storing information indicating a correspondence relationship between the second rotation speed and the third weight, and the third calculation unit is set to the second rotation speed. The amplitude value of the torque ripple of the motor allows at least one amplitude value of the pulsation amplitude value included, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value. The second weight is obtained by PI control so as to be the target amplitude value which is at least one amplitude value when the value is equal to or less than the value, and with reference to the information, the said corresponding to the second rotation speed. The third weight may be obtained, and the multiplication value of the second weight and the third weight may be configured to be the first weight.

Further, the third calculation unit is based on the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value. It may be configured to obtain the first weight.

As a result, when the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value are relatively large, that is, the rotor When there is a high possibility that the amplitude value of each pulsation is relatively large due to the influence of the quantization error included in the position, the first rotation number that is not affected by the quantization error included in the rotor position is the third. Since the first weight can be set so as to be the number of revolutions of, the drive of the motor can be controlled by using the third number of revolutions that is not affected by the quantization error included in the position of the rotor. It is possible to suppress the amplitude value of the pulsation included in the current flowing through the motor and the voltage command value, and it is possible to suppress the torque ripple of the motor.

According to the present invention, in a control device that controls the drive of a motor by using the rotation speed calculated by the current flowing through the motor and the rotation speed of the motor calculated by the position of the rotor, the sensor uses only the rotation speed of the motor. It is possible to suppress torque ripple that cannot be suppressed when switching between use control and sensorless control is determined.

It is a figure which shows an example of the control device of the motor of an embodiment. It is a figure which shows an example of the information which is stored in the storage part. It is a flowchart which shows the operation of the 3rd calculation part in 1st Example. It is a flowchart which shows the operation of the 3rd calculation part in 2nd Example. It is a flowchart which shows the operation of the 3rd calculation part in 3rd Example. It is a flowchart which shows the operation of the 3rd calculation part in 4th Example.

The embodiment will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing an example of a motor control device according to an embodiment.

The control device 1 shown in FIG. 1 is, for example, a control device for driving a motor M (three-phase induction motor, three-phase synchronous motor, etc.) mounted on a vehicle (electric forklift, plug-in hybrid vehicle, etc.). , Inverter circuit 2 and control circuit 3. The motor M detects the position θ (phase from the reference position of the rotor to the current position) of the rotor (rotor), and outputs the detected position θ to the control circuit 3 Electric angle detection unit Sp (resolver). Etc.).

The inverter circuit 2 drives the motor M by converting the direct current power supplied from the power supply P into AC power, and includes a capacitor C and switching elements SW1 to SW6 (IGBT (Insulated Gate Bipolar Transistor) or the like). , The current sensors Si1 and Si2 are provided. That is, one end of the capacitor C is connected to the positive electrode terminal of the power supply P and each collector terminal of the switching elements SW1, SW3, SW5, and the other end of the capacitor C is the negative electrode terminal of the power supply P and each of the switching elements SW2, SW4, SW6. It is connected to the emitter terminal. The connection point between the emitter terminal of the switching element SW1 and the collector terminal of the switching element SW2 is connected to the input terminal of the U phase of the motor M via the current sensor Si1. The connection point between the emitter terminal of the switching element SW3 and the collector terminal of the switching element SW4 is connected to the input terminal of the V phase of the motor M via the current sensor Si2. The connection point between the emitter terminal of the switching element SW5 and the collector terminal of the switching element SW6 is connected to the input terminal of the W phase of the motor M.

The capacitor C smoothes the voltage output from the power supply P to the inverter circuit 2.

The switching element SW1 is turned on when the drive signal S1 output from the control circuit 3 is at a high level, and is turned off when the drive signal S1 is at a low level. The switching element SW2 is turned on when the drive signal S2 output from the control circuit 3 is at a high level, and is turned off when the drive signal S2 is at a low level. The switching element SW3 is turned on when the drive signal S3 output from the control circuit 3 is at a high level, and is turned off when the drive signal S3 is at a low level. The switching element SW4 is turned on when the drive signal S4 output from the control circuit 3 is at a high level, and is turned off when the drive signal S4 is at a low level. The switching element SW5 is turned on when the drive signal S5 output from the control circuit 3 is at a high level, and is turned off when the drive signal S5 is at a low level. The switching element SW6 is turned on when the drive signal S6 output from the control circuit 3 is at a high level, and is turned off when the drive signal S6 is at a low level.

By repeatedly turning on and off the switching elements SW1 to SW6, the DC voltage output from the power supply P is converted into AC voltages Vu, Vv, and Vw whose phases differ by 120 degrees from each other. Then, the AC voltage Vu is applied to the input terminal of the U phase of the motor M, the AC voltage Vv is applied to the input terminal of the V phase of the motor M, and the AC voltage Vw is applied to the input terminal of the W phase of the motor M. As a result, alternating currents Iu, Iv, and Iw whose phases differ by 120 degrees from each other flow through the motor M, and the rotor of the motor M rotates.

The current sensor Si1 is composed of a Hall element, a shunt resistance, and the like, and detects the alternating current Iu flowing in the U phase of the motor M and outputs it to the control circuit 3. Further, the current sensor Si2 is composed of a Hall element, a shunt resistor, and the like, and detects the alternating current Iv flowing in the V phase of the motor M and outputs it to the control circuit 3.

The control circuit 3 includes a storage unit 4, a drive circuit 5, and a calculation unit 6.

The storage unit 4 is composed of a RAM (Random Access Memory), a ROM (Read Only Memory), or the like.

FIG. 2A is a diagram showing an example (No. 1) of the information described in the storage unit 4. The horizontal axis of the two-dimensional coordinates shown in FIG. 2A indicates the amplitude value Aω of the pulsation included in the rotation speed ω2, and the vertical axis indicates the weight w1 (first weight). Further, the solid line shown in FIG. 2A is information D1 showing the correspondence between the amplitude value Aω and the weight w1. Further, the weight w1 is a ratio in which the rotation speed ω1 and the rotation speed ω2 are reflected in the rotation speed ω3. That is, it is the ratio of the rotation speed ω1 to the rotation speed ω3 obtained by using the rotation speed ω1 and the rotation speed ω2, or the ratio of the rotation speed ω2 to the rotation speed ω3 obtained by using the rotation speed ω1 and the rotation speed ω2. Further, the weight w1 is a ratio in which the position θ1 and the position θ2 are reflected in the position θ3. That is, it is the ratio of the position θ1 to the position θ3 obtained by using the position θ1 and the position θ2, or the ratio of the position θ2 to the position θ3 obtained by using the position θ1 and the position θ2.

In the information D1 shown in FIG. 2A, when the amplitude value Aω is smaller than the amplitude value Aω1, the weight w1 is zero. Further, in the information D1, when the amplitude value Aω is equal to or greater than the amplitude value Aω1 and the amplitude value Aω is equal to or less than the amplitude value Aω2, the larger the amplitude value Aω, the larger the weight w1. It should be noted that the amplitude value Aω1 <amplitude value Aω2 and 0 <weight w1 <1. Further, in the information D1, when the amplitude value Aω is larger than the amplitude value Aω2, the weight w1 is 1.

FIG. 2B is a diagram showing an example (No. 2) of the information described in the storage unit 4. The horizontal axis of the two-dimensional coordinates shown in FIG. 2B shows the amplitude value Ai of the pulsation included in the current Iq, and the vertical axis shows the weight w1. Further, the solid line shown in FIG. 2B is information D2 showing the correspondence between the amplitude value Ai and the weight w1.

In the information D2 shown in FIG. 2B, when the amplitude value Ai is smaller than the amplitude value Ai1, the weight w1 is zero. Further, in the information D2, when the amplitude value Ai is equal to or greater than the amplitude value Ai1 and the amplitude value Ai is equal to or less than the amplitude value Ai2, the larger the amplitude value Ai, the larger the weight w1. It should be noted that the amplitude value Ai1 <amplitude value Ai2 and 0 <weight w1 <1. Further, in the information D2, when the amplitude value Ai is larger than the amplitude value Ai2, the weight w1 is 1.

FIG. 2C is a diagram showing an example (No. 3) of the information described in the storage unit 4. The horizontal axis of the two-dimensional coordinates shown in FIG. 2C shows the amplitude value Av of the pulsation included in the voltage command value Vq *, and the vertical axis shows the weight w1. Further, the solid line shown in FIG. 2C is information D3 showing the correspondence between the amplitude value Av and the weight w1.

In the information D3 shown in FIG. 2 (c), when the amplitude value Av is smaller than the amplitude value Av1, the weight w1 is zero. Further, in the information D3, when the amplitude value Av is equal to or greater than the amplitude value Av1 and the amplitude value Av is equal to or less than the amplitude value Av2, the larger the amplitude value Av, the larger the weight w1. It should be noted that the amplitude value Av1 <amplitude value Av2 and 0 <weight w1 <1. Further, in the information D3, when the amplitude value Av is larger than the amplitude value Av2, the weight w1 is 1.

FIG. 2D is a diagram showing an example (No. 4) of the information described in the storage unit 4. The horizontal axis of the two-dimensional coordinates shown in FIG. 2D indicates the rotation speed ω2, and the vertical axis indicates the weight w3 (third weight). Further, the solid line shown in FIG. 2D is information D4 showing the correspondence relationship between the rotation speed ω2 and the weight w2.

In the information D4 shown in FIG. 2D, when the rotation speed ω2 is smaller than the rotation speed ω21, the weight w3 is zero. Further, in the information D4, when the rotation speed ω2 is the rotation speed ω21 or more and the rotation speed ω2 is the rotation speed ω22 or less, the weight w3 increases as the rotation speed ω2 increases. It should be noted that the rotation speed ω21 <rotation speed ω22 and 0 <weight w3 <1. Further, in the information D4, when the rotation speed ω2 is larger than the rotation speed ω22, the weight w3 is 1.

Further, the drive circuit 5 shown in FIG. 1 is composed of an IC (Integrated Circuit) or the like, and has a U-phase voltage command value Vu *, a V-phase voltage command value Vv *, and a W-phase voltage command value output from the arithmetic unit 6. Vw * is compared with the voltage value of the carrier, and the drive signals S1 to S6 corresponding to the comparison result are output to the respective gate terminals of the switching elements SW1 to SW6. The carrier wave is a triangular wave, a sawtooth wave (sawtooth wave), a reverse sawtooth wave, or the like.

For example, when the U-phase voltage command value Vu * is equal to or higher than the carrier voltage value, the drive circuit 5 outputs a high-level drive signal S1 and a low-level drive signal S2, and outputs a U-phase voltage command value Vu. When * is smaller than the voltage value of the carrier wave, the low level drive signal S1 is output and the high level drive signal S2 is output. Further, when the V-phase voltage command value Vv * is equal to or higher than the carrier voltage value, the drive circuit 5 outputs a high-level drive signal S3 and a low-level drive signal S4 to output a V-phase voltage command value Vv. When * is smaller than the voltage value of the carrier wave, the low level drive signal S3 is output and the high level drive signal S4 is output. Further, when the W-phase voltage command value Vw * is equal to or higher than the carrier voltage value, the drive circuit 5 outputs a high-level drive signal S5 and a low-level drive signal S6 to output a W-phase voltage command value Vw. When * is smaller than the voltage value of the carrier wave, the low level drive signal S5 is output and the high level drive signal S6 is output.

The calculation unit 6 is composed of a microcomputer or the like, and includes a first calculation unit 71, a second calculation unit 72, a third calculation unit 73, a subtraction unit 8, a torque control unit 9, and a torque / current. It includes a command value conversion unit 10, a coordinate conversion unit 11, a subtraction unit 12, a subtraction unit 13, a current control unit 14, and a coordinate conversion unit 15. For example, by executing the program stored in the storage unit 4, the microcomputer executes the first calculation unit 71, the second calculation unit 72, the third calculation unit 73, the subtraction unit 8, the torque control unit 9, and the like. A torque / current command value conversion unit 10, a coordinate conversion unit 11, a subtraction unit 12, a subtraction unit 13, a current control unit 14, and a coordinate conversion unit 15 are configured.

The first calculation unit 71 uses the current Iu detected by the current sensor Si1 and the current Iv detected by the current sensor Si2 to obtain the alternating current Iw flowing in the W phase of the motor M. The current detected by the current sensors Si1 and Si2 is not limited to the combination of the currents Iu and Iv, and may be a combination of the currents Iv and Iw or a combination of the currents Iu and Iw. When the currents Iv and Iw are detected by the current sensors Si1 and Si2, the first calculation unit 71 obtains the currents Iu using the currents Iv and Iw. When the currents Iu and Iw are detected by the current sensors Si1 and Si2, the first calculation unit 71 obtains the currents Iv using the alternating currents Iu and Iw.

Further, the first calculation unit 71 is the voltage of the d-axis current Id and the q-axis current Iq output from the coordinate conversion unit 11 and the voltage command values Vd * and q of the d-axis output from the current control unit 14. The rotation speed ω1 (first rotation speed) and the position θ1 are calculated using the command value Vq *. For example, the first calculation unit 71 obtains the rotation speed ω1 using the voltage equation shown in the following equation 1, and multiplies the obtained rotation speed ω1 by a predetermined time (clock cycle of the calculation unit 6 or the like) to position the position. Find θ1. R is the resistance component of the coil constituting the motor M, p is the differential operator, Ld is the d-axis inductance of the coil constituting the motor M, and Lq is the q-axis inductance of the coil constituting the motor M. Ke is an induced voltage constant.

The second calculation unit 72 calculates the rotation speed ω2 (second rotation speed) of the motor M using the position θ detected by the electric angle detection unit Sp. For example, the second calculation unit 72 obtains the rotation speed ω2 by dividing the position θ by a predetermined time (clock cycle of the calculation unit 6 or the like). Further, the second calculation unit 72 outputs the position θ detected by the electric angle detection unit Sp as the position θ2.

The third calculation unit 73 calculates the rotation speed ω3 using the rotation speeds ω1 and ω2, and calculates the position θ3 using the positions θ1 and θ2w.

The subtraction unit 8 calculates the rotation speed difference Δω between the rotation speed command value ω * input from the outside and the rotation speed ω3 output from the third calculation unit 73.

The torque control unit 9 outputs the torque command value T * using the rotation speed difference Δω output from the subtraction unit 8. For example, the torque control unit 9 refers to the information stored in the storage unit 4 in which the rotation speed of the motor M and the torque of the motor M are associated with each other, and the rotation speed corresponding to the rotation speed difference Δω. The torque corresponding to is output as the torque command value T *.

The torque / current command value conversion unit 10 converts the torque command value T * output from the torque control unit 9 into the current command value Id * on the d-axis and the current command value Iq * on the q-axis. For example, the torque / current command value conversion unit 10 refers to the information stored in the storage unit 4 in which the torque of the motor M, the current command value Id *, and the current command value Iq * are associated with each other. , The current command value Id * and the current command value Iq * corresponding to the torque corresponding to the torque command value T * are output.

The coordinate conversion unit 11 obtains the current Iw flowing in the W phase of the motor M by using the current Iu detected by the current sensor Si1 and the current Iv detected by the current sensor Si2. The current detected by the current sensors Si1 and Si2 is not limited to the combination of the currents Iu and Iv, and may be a combination of the currents Iv and Iw or a combination of the currents Iu and Iw. When the currents Iv and Iw are detected by the current sensors Si1 and Si2, the coordinate conversion unit 11 obtains the currents Iu using the currents Iv and Iw. When the currents Iu and Iw are detected by the current sensors Si1 and Si2, the coordinate conversion unit 11 obtains the currents Iv using the currents Iu and Iw.

Further, the coordinate conversion unit 11 uses the position θ3 output from the third calculation unit 73 to set the currents Iu, Iv, and Iw to the d-axis current Id (current component for controlling the back electromotive force) and q. It is converted into a shaft current Iq (current component for controlling torque). For example, the coordinate conversion unit 11 converts the currents Iu, Iv, and Iw into the currents Id and the currents Iq by using the transformation matrix C1 shown in the following equation 2.

Further, when the inverter circuit 2 further includes a current sensor Si3 for detecting the current Iw flowing in the W phase of the motor M in addition to the current sensors Si1 and Si2, the coordinate conversion unit 11 outputs from the third calculation unit 73. The currents Iu, Iv, and Iw detected by the current sensors Si1 to Si3 may be converted into the current Id and the current Iq by using the position θ3.

The subtraction unit 12 calculates the current difference ΔId between the current command value Id * output from the torque / current command value conversion unit 10 and the current Id output from the coordinate conversion unit 11.

The subtraction unit 13 calculates the current difference ΔIq between the current command value Iq * output from the torque / current command value conversion unit 10 and the current Iq output from the coordinate conversion unit 11.

The current control unit 14 controls the voltage command value Vd * on the d-axis and the voltage on the q-axis by PI (Proportional Integral) control using the current difference ΔId output from the subtraction unit 12 and the current difference ΔIq output from the subtraction unit 13. Calculate the command value Vq *. For example, the current control unit 14 calculates the voltage command value Vd * using the following formula 3 and calculates the voltage command value Vq * using the following formula 4. Kp is a constant of the proportional term of PI control, Ki is a constant of the integral term of PI control, Lq is the q-axis inductance of the coil constituting the motor M, and Ld is the d-axis inductance of the coil constituting the motor M. Let ω3 be the number of revolutions ω3 output from the third calculation unit 73, and Ke be the induced voltage constant.

Voltage command value Vd * = Kp × current difference ΔId + Ki × ∫ (current difference ΔId) −ω3 × Lq × Iq ・ ・ ・ Equation 3
Voltage command value Vq * = Kp × current difference ΔIq + Ki × ∫ (current difference ΔIq) + ω3 × Ld × Id + ω3 × Ke ・ ・ ・ Equation 4

That is, the current control unit 14 calculates the voltage command value Vd * so that the current difference ΔId between the current Id and the current command value Id * becomes small, and the current difference ΔIq between the current Iq and the current command value Iq * is small. The voltage command value Vq * is calculated so as to be.

The coordinate conversion unit 15 uses the position θ3 output from the third calculation unit 73 to obtain the voltage command value Vd * and the voltage command value Vq *, the U-phase voltage command value Vu *, and the V-phase voltage command value Vv *. , And W phase voltage command value Vw *. For example, the coordinate conversion unit 15 uses the transformation matrix C2 shown in the following equation 5 to convert the voltage command value Vd * and the voltage command value Vq * into the U-phase voltage command value Vu *, the V-phase voltage command value Vv *, and the voltage command value Vv *. Convert to W phase voltage command value Vw *.

It is assumed that the subtraction unit 8, the torque control unit 9, the torque / current command value conversion unit 10, the coordinate conversion unit 11, the subtraction unit 12, the subtraction unit 13, and the current control unit 14 constitute a command value output unit. .. That is, the command value output unit outputs the voltage command values Vd * and Vq * based on the rotation speed difference Δω between the rotation speed ω3 output from the third calculation unit 73 and the rotation speed command value ω *.

<First Example>
FIG. 3 is a flowchart showing an example of the operation of the third calculation unit 73 in the first embodiment.

First, in step S11, the third calculation unit 73 includes the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current Iq, or the pulsation amplitude value included in the voltage command value Vq *. Calculate Av.

For example, the third calculation unit 73 sets the difference between the maximum value and the minimum value of the rotation speed ω2 when the rotation speed command value ω * is constant in a fixed period longer than the clock cycle of the calculation unit 6, and the rotation speed ω2. Let the amplitude value Aω of the pulsation included in.

Further, the third calculation unit 73 includes the difference between the maximum value and the minimum value of the current Iq when the rotation speed command value ω * is constant in a fixed period longer than the clock cycle of the calculation unit 6 in the current Iq. Let the amplitude value Ai of the pulsation to be generated.

Further, the third calculation unit 73 sets the difference between the maximum value and the minimum value of the voltage command value Vq * when the rotation speed command value ω * is constant for a fixed period longer than the clock cycle of the calculation unit 6. Let the amplitude value Av of the pulsation of the command value Vq *.

Next, in step S12, the third calculation unit 73 includes the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current Iq, or the amplitude value Av included in the voltage command value Vq *. The weight w1 is obtained by.

<When the weight w1 is obtained from the amplitude value Aω of the pulsation included in the rotation speed ω2 (1)>
The third calculation unit 73 refers to the information D1 stored in the storage unit 4 and obtains the weight w1 corresponding to the amplitude value Aω. That is, when the amplitude value Aω is smaller than the amplitude value Aω1, the third calculation unit 73 sets the weight w1 to zero. Further, when the amplitude value Aω is equal to or greater than the amplitude value Aω1 and the amplitude value Aω is equal to or less than the amplitude value Aω2, the third calculation unit 73 increases the weight w1 as the amplitude value Aω increases. Further, the third calculation unit 73 sets the weight w1 to 1 when the amplitude value Aω is larger than the amplitude value Aω2. The amplitude value Aω1 is the maximum value of the amplitude value Aω when the torque ripple amplitude value of the motor M is equal to or less than the allowable value when the rotation speed ω2 is output from the third calculation unit 73 as the rotation speed ω3. And. Further, the amplitude value Aω2 is the minimum value of the amplitude value Aω when the amplitude value of the torque ripple of the motor M is equal to or less than the allowable value when the rotation speed ω1 is output from the third calculation unit 73 as the rotation speed ω3. And.

<When the weight w1 is obtained from the amplitude value Aω of the pulsation included in the rotation speed ω2 (2)>
The third calculation unit 73 obtains the weight w1 by the PI control shown in the following equation 6. That is, the third calculation unit 73 obtains the weight w1 by PI control so that the amplitude value Aω of the pulsation included in the rotation speed ω2 becomes the target amplitude value Aω0. For example, the third calculation unit 73 obtains the weight w1 by PI control so that the difference between the amplitude value Aω of the pulsation included in the rotation speed ω2 and the target amplitude value Aω0 becomes zero. The proportional term wp is the following equation 7, and the integral term wi is the following equation 8. Further, the target amplitude value Aω0 is an arbitrary amplitude value Aω when the amplitude value of the torque ripple of the motor M is equal to or less than the allowable value.

Weight w1 = Proportional term wp + Integral term wi ... Equation 6
Proportional term wp = (amplitude value Aω-target amplitude value Aω0) × proportionality constant Kp ・ ・ ・ Equation 7
Integral term wi = Integral term wi calculated last time + (amplitude value Aω-target amplitude value Aω0) × constant constant Ki ・ ・ ・ Equation 8

<When the weight w1 is obtained from the pulsation amplitude value Ai included in the current Iq (No. 1)>
The third calculation unit 73 refers to the information D2 stored in the storage unit 4 and obtains the weight w1 corresponding to the amplitude value Ai. That is, when the amplitude value Ai is smaller than the amplitude value Ai1, the third calculation unit 73 sets the weight w1 to zero. Further, when the amplitude value Ai is equal to or greater than the amplitude value Ai1 and the amplitude value Ai is equal to or less than the amplitude value Ai2, the third calculation unit 73 increases the weight w1 as the amplitude value Ai increases. Further, the third calculation unit 73 sets the weight w1 to 1 when the amplitude value Ai is larger than the amplitude value Ai2. The amplitude value Ai1 is the maximum value of the amplitude value Ai when the torque ripple amplitude value of the motor M is equal to or less than the allowable value when the rotation speed ω2 is output from the third calculation unit 73 as the rotation speed ω3. And. Further, the amplitude value Ai2 is the minimum value of the amplitude value Ai when the amplitude value of the torque ripple of the motor M is equal to or less than the allowable value when the rotation speed ω1 is output as the rotation speed ω3 from the third calculation unit 73. And.

<When the weight w1 is obtained from the pulsation amplitude value Ai included in the current Iq (Part 2)>
The third calculation unit 73 obtains the weight w1 by the PI control shown in the above equation 6. That is, the third calculation unit 73 obtains the weight w1 by PI control so that the amplitude value Ai of the pulsation included in the current Iq becomes the target amplitude value Ai0. For example, the third calculation unit 73 obtains the weight w1 by PI control so that the difference between the pulsation amplitude value Ai included in the current Iq and the target amplitude value Ai0 becomes zero. The proportional term wp is the following equation 9, and the integral term wi is the following equation 10. Further, the target amplitude value Ai0 is an arbitrary amplitude value Ai when the amplitude value of the torque ripple of the motor M is equal to or less than the allowable value.

Proportional term wp = (amplitude value Ai-target amplitude value Ai0) × proportionality constant Kp ・ ・ ・ Equation 9
Integral term wi = Integral term wi calculated last time + (amplitude value Ai-target amplitude value Ai0) × constant constant Ki ・ ・ ・ Equation 10

The third calculation unit 73 may be configured to calculate the weight w1 from the pulsation amplitude value Ai included in the current Id instead of the pulsation amplitude value Ai included in the current Iq.

Further, the third calculation unit 73 uses the pulsation amplitude value Ai or the current command value Iq * included in the current command value Id * output from the torque / current command value conversion unit 10 instead of the currents Id and Iq. The weight w1 may be calculated from the amplitude value Ai of the included pulsation.

<When the weight w1 is obtained from the pulsation amplitude value Av included in the voltage command value Vq * (No. 1)>
The third calculation unit 73 refers to the information D3 stored in the storage unit 4 and obtains the weight w1 corresponding to the amplitude value Av. That is, when the amplitude value Av is smaller than the amplitude value Av1, the third calculation unit 73 sets the weight w1 to zero. Further, when the amplitude value Av is equal to or greater than the amplitude value Av1 and the amplitude value Av is equal to or less than the amplitude value Av2, the third calculation unit 73 increases the weight w1 as the amplitude value Av increases. Further, the third calculation unit 73 sets the weight w1 to 1 when the amplitude value Av is larger than the amplitude value Av2. The amplitude value Av1 is the maximum value of the amplitude value Av when the torque ripple amplitude value of the motor M is equal to or less than the allowable value when the rotation speed ω2 is output from the third calculation unit 73 as the rotation speed ω3. And. Further, the amplitude value Av2 is the minimum value of the amplitude value Av when the torque ripple amplitude value of the motor M is equal to or less than the allowable value when the rotation speed ω1 is output as the rotation speed ω3 from the third calculation unit 73. And.

<When the weight w1 is obtained from the pulsation amplitude value Av included in the voltage command value Vq * (Part 2)>
The third calculation unit 73 obtains the weight w1 by the PI control shown in the above equation 6. That is, the third calculation unit 73 obtains the weight w1 by PI control so that the amplitude value Av of the pulsation included in the voltage command value Vq * becomes the target amplitude value Av0. For example, the third calculation unit 73 obtains the weight w1 by PI control so that the difference between the pulsation amplitude value Av included in the voltage command value Vq * and the target amplitude value Av0 becomes zero. The proportional term wp is the following equation 11, and the integral term wi is the following equation 12. Further, the target amplitude value Av0 is an arbitrary amplitude value Av when the amplitude value of the torque ripple of the motor M is equal to or less than the allowable value.

Proportional term wp = (amplitude value Av-target amplitude value Av0) × proportionality constant Kp ・ ・ ・ Equation 11
Integral term wi = Integral term wi calculated last time + (amplitude value Av-target amplitude value Av0) × constant constant Ki ・ ・ ・ Equation 12

The third calculation unit 73 is configured to calculate the weight w1 by the pulsation amplitude value Av included in the voltage command value Vd * instead of the pulsation amplitude value Av included in the voltage command value Vq *. You may.

Then, in step S13, the third calculation unit 73 calculates the rotation speed ω3 and the position θ3 by the weight w1, the rotation speeds ω1, ω2, and the positions θ1 and θ2. For example, the third calculation unit 73 calculates the rotation speed ω3 by the following formula 13, and calculates the position θ3 by the following formula 14.

Rotation speed ω3 = weight w1 x rotation speed ω1 + (1-weight w1) x rotation speed ω2 ... Equation 13
Position θ3 = weight w1 × position θ1 + (1-weight w1) × position θ2 ・ ・ ・ Equation 14

For example, when the amplitude value Aω of the pulsation included in the rotation speed ω2 is smaller than the amplitude value Aω1, the third calculation unit 73 obtains zero as the weight w1 and obtains the rotation speed ω2 as the rotation speed ω3. In this way, when the pulsation amplitude value Aω included in the rotation speed ω2 is relatively small and the possibility of torque ripple occurring due to the influence of the quantization error included in the position θ is low, the rotation speed ω2 is close to the actual rotation speed. Is output from the third calculation unit 73 as the rotation speed ω3.

Further, when the amplitude value Aω is larger than the amplitude value Aω2, the third calculation unit 73 obtains 1 as the weight w1 and calculates the rotation speed ω1 as the rotation speed ω3. In this way, when the pulsation amplitude value Aω included in the rotation speed ω2 is relatively large and there is a high possibility that torque ripple will occur due to the influence of the quantization error included in the position θ, the quantization error included in the position θ The unaffected rotation speed ω1 is output from the third calculation unit 73 as the rotation speed ω3.

In the third calculation unit 73, when the amplitude value Ai of the pulsation included in the current (current Id, current Iq, current command value Id *, or current command value Iq *) flowing through the motor M is smaller than the amplitude value Ai1. , Zero is calculated as the weight w1, and the rotation number ω2 is calculated as the rotation number ω3. As described above, when the pulsation amplitude value Ai included in the current flowing through the motor M is relatively small and the possibility of torque ripple occurring due to the influence of the quantization error included in the position θ is low, the rotation is close to the actual rotation speed. The number ω2 is output from the third calculation unit 73 as the rotation speed ω3.

Further, when the amplitude value Ai is larger than the amplitude value Ai2, the third calculation unit 73 obtains 1 as the weight w1 and calculates the rotation speed ω1 as the rotation speed ω3. In this way, when the amplitude value Ai of the pulsation included in the current flowing through the motor M is relatively large and there is a high possibility that torque ripple will occur due to the influence of the quantization error included in the position θ, the quantization included in the position θ. The rotation speed ω1 that is not affected by the error is output as the rotation speed ω3 from the third calculation unit 73.

Further, when the amplitude value Av of the pulsation included in the voltage command value (voltage command value Vd * or voltage command value Vq *) is smaller than the amplitude value Av1, the third calculation unit 73 calculates zero as the weight w1. The rotation number ω2 is calculated as the rotation number ω3. In this way, when the amplitude value Av of the pulsation included in the voltage command value is relatively small and the possibility of torque ripple occurring due to the influence of the quantization error included in the position θ is low, the rotation speed ω2 is close to the actual rotation speed. Is output from the third calculation unit 73 as the rotation speed ω3.

Further, when the amplitude value Av is larger than the amplitude value Av2, the third calculation unit 73 obtains 1 as the weight w1 and calculates the rotation speed ω1 as the rotation speed ω3. In this way, when the amplitude value Av of the pulsation included in the voltage command value is relatively large and there is a high possibility that torque ripple will occur due to the influence of the quantization error included in the position θ, the quantization error included in the position θ The unaffected rotation speed ω1 is output from the third calculation unit 73 as the rotation speed ω3.

The third calculation unit 73 may be configured to calculate the rotation speed ω3 by the following formula 15 and calculate the position θ3 by the following formula 16. In this configuration, in the information D1 stored in the storage unit 4, when the amplitude value Aω is smaller than the amplitude value Aω1, the weight w1 becomes 1. Further, in the information D1, when the amplitude value Aω is equal to or greater than the amplitude value Aω1 and the amplitude value Aω is equal to or less than the amplitude value Aω2, the larger the amplitude value Aω, the smaller the weight w1. Further, in the information D1, when the amplitude value Aω is larger than the amplitude value Aω2, the weight w1 becomes zero. Further, in the information D2 stored in the storage unit 4, when the amplitude value Ai is smaller than the amplitude value Ai1, the weight w1 becomes 1. Further, in the information D2, when the amplitude value Ai is equal to or greater than the amplitude value Ai1 and the amplitude value Ai2 is equal to or less than the amplitude value Aω2, the larger the amplitude value Ai, the smaller the weight w1. Further, in the information D2, when the amplitude value Ai is larger than the amplitude value Ai2, the weight w1 becomes zero. Further, in the information D3 stored in the storage unit 4, when the amplitude value Av is smaller than the amplitude value Av1, the weight w1 becomes 1. Further, in the information D3, when the amplitude value Av is equal to or greater than the amplitude value Av1 and the amplitude value Av is equal to or less than the amplitude value Av2, the larger the amplitude value Av, the smaller the weight w1. Further, in the information D2, when the amplitude value Av is larger than the amplitude value Av2, the weight w1 becomes zero.

Rotation speed ω3 = (1-weight w1) x rotation speed ω1 + weight w1 x rotation speed ω2 ... Equation 15
Position θ3 = (1-weight w1) × position θ1 + weight w1 × position θ2 ・ ・ ・ Equation 16

Here, as in the conventional control device, when the rotation speed ω2 is smaller than the threshold value, the drive of the motor M is controlled by using the rotation speed ω2, and when the rotation speed ω2 is equal to or more than the threshold value, the rotation speed ω1 is used. It is assumed that the drive of the motor M is controlled. The sensor use control is to control the drive of the motor M by using the rotation speed ω2. Further, controlling the drive of the motor M by using the rotation speed ω1 is defined as sensorless control.

In this case, even though the amplitude value of the pulsation included in the rotation speed ω2 exceeds the allowable value, in the state where the rotation speed ω2 is smaller than the threshold value, the drive of the motor M can be controlled by using the rotation speed ω1. Can not.

On the other hand, when switching between the rotation speed ω1 and the rotation speed ω2 as the rotation speed ω3 by using the pulsation amplitude value included in the rotation speed ω2 as in the first embodiment, the amplitude of the pulsation included in the rotation speed ω2. When the value exceeds the permissible value, the drive of the motor M can be controlled by using the rotation speed ω1.

As described above, according to the first embodiment, the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current flowing through the motor M, or the pulsation amplitude value Av included in the voltage command value. Is relatively large, that is, when there is a high possibility that the pulsation amplitude value is relatively large due to the influence of the quantization error included in the position θ, there is no influence of the quantization error included in the position θ. The rotation number ω1 can be set to the rotation number ω3. As a result, the drive of the motor M can be controlled by using the rotation speed ω3 that is not affected by the quantization error included in the position θ, so that the current flowing through the motor M and the pulsating amplitude value included in the voltage command value can be controlled. It can be suppressed, and the torque ripple of the motor M, which cannot be suppressed when the switching between the sensor use control and the sensorless control is determined using only the rotation speed ω2 of the motor M, can be suppressed.

Further, according to the first embodiment, when switching from the rotation speed ω2 to the rotation speed ω1 as the rotation speed ω3, the rotation speed ω1 can be gradually changed from the rotation speed ω2 to the rotation speed ω1 or the rotation speed ω3. When switching from the rotation speed ω1 to the rotation speed ω2, the rotation speed ω1 can be gradually changed from the rotation speed ω1 to the rotation speed ω2. Compared with the case of abruptly switching to the number ω2, the fluctuation of the rotation speed ω3 due to the influence of the measurement error of the current sensors Si1 and Si2 can be suppressed, so that the fluctuation of the torque of the motor M can be suppressed.

Further, in the case of obtaining the weight w1 using the information D1 to D3 in the first embodiment, the load of the calculation process on the third calculation unit 73 can be reduced.

Further, in the first embodiment, when the weight w1 is obtained by PI control, it is not necessary to prepare information indicating the correspondence between the pulsation amplitude value and the weight w1 in advance, and the man-hours for obtaining the weight w1 are reduced. can do.

<Second Example>
FIG. 4 is a flowchart showing an example of the operation of the third calculation unit 73 in the second embodiment. Since step S21 shown in FIG. 4 is the same as step S11 shown in FIG. 3, and step S23 shown in FIG. 4 is the same as step S13 shown in FIG. 3, the description of steps S21 and S23 will be omitted.

In step S22, the third calculation unit 73 rotates with the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current Iq, or the amplitude value Av included in the voltage command value Vq *. The weight w1 is calculated by the number ω2.

<When the weight w1 is obtained from the pulsation amplitude value Aω included in the rotation speed ω2 and the rotation speed ω2>
First, the third calculation unit 73 obtains the weight w1 by the PI control shown in the above equations 6, 7, and 8, and sets the obtained weight w1 as the weight w2 (second weight).

Next, the third calculation unit 73 refers to the information D4 stored in the storage unit 4 and obtains the weight w3 corresponding to the rotation speed ω2. That is, when the rotation speed ω2 is smaller than the rotation speed ω21, the third calculation unit 73 sets the weight w3 to zero. Further, the third calculation unit 73 increases the weight w3 as the rotation speed ω2 increases when the rotation speed ω2 is the rotation speed ω21 or more and the rotation speed ω2 is the rotation speed ω22 or less. Further, the third calculation unit 73 sets the weight w3 to 1 when the rotation speed ω2 is larger than the rotation speed ω22. The rotation speed ω21 is the maximum value of the rotation speed ω2 when the torque ripple amplitude value of the motor M is equal to or less than the allowable value when the rotation speed ω2 is output as the rotation speed ω3 from the third calculation unit 73. And. Further, the rotation speed ω22 is the minimum value of the rotation speed ω2 when the torque ripple amplitude value of the motor M is equal to or less than the allowable value when the rotation speed ω1 is output as the rotation speed ω3 from the third calculation unit 73. And.

Then, the third calculation unit 73 sets the multiplication value of the weight w2 and the weight w3 as the weight w1 used in step S23.

<When the weight w1 is obtained from the pulsation amplitude value Ai included in the current Iq and the rotation speed ω2>
First, the third calculation unit 73 calculates the weight w1 by the PI control shown in the above equations 6, 9, and 10, and the calculated weight w1 is set as the weight w2.

Next, the third calculation unit 73 refers to the information D4 stored in the storage unit 4 and obtains the weight w3 corresponding to the rotation speed ω2.

Then, the third calculation unit 73 sets the multiplication value of the weight w2 and the weight w3 as the weight w1 used in step S23.

The third calculation unit 73 may be configured to obtain the weight w2 from the pulsation amplitude value Ai included in the current Id instead of the pulsation amplitude value Ai included in the current Iq.

Further, the third calculation unit 73 uses the pulsation amplitude value Ai or the current command value Iq * included in the current command value Id * output from the torque / current command value conversion unit 10 instead of the currents Id and Iq. The weight w2 may be obtained from the amplitude value Ai of the included pulsation.

<When calculating the weight w1 from the pulsation amplitude value Ai included in the voltage command value Vq * and the rotation speed ω2>
First, the third calculation unit 73 calculates the weight w1 by the PI control shown in the above equations 6, 13, and 14, and the calculated weight w1 is set as the weight w2.

Next, the third calculation unit 73 refers to the information D4 stored in the storage unit 4 and obtains the weight w3 corresponding to the rotation speed ω2.

Then, the third calculation unit 73 sets the multiplication value of the weight w2 and the weight w3 as the weight w1 used in step S23.

The third calculation unit 73 is configured to obtain the weight w2 from the pulsation amplitude value Av included in the voltage command value Vd * instead of the pulsation amplitude value Av included in the voltage command value Vq *. May be good.

For example, when the difference between the pulsation amplitude value Aω included in the rotation speed ω2 and the target amplitude value Aω0 is relatively large, and when the rotation speed ω2 is smaller than the rotation speed ω21, the weight w2 becomes a value close to 1. Nevertheless, since the weight w3 becomes zero, the weight w1 which is the multiplication value of the weight w2 and the weight w3 becomes zero, and the rotation speed ω2 is output from the third output unit 73 as the rotation speed ω3. As described above, when the rotation speed ω2 is relatively small even though the pulsation amplitude value Aω included in the rotation speed ω2 is relatively large, that is, the pulsation amplitude due to factors other than the quantization error included in the position θ. When there is a high possibility that the value Aω is relatively large, the third calculation is based on the rotation speed ω2, which is close to the actual rotation speed, instead of the rotation speed ω1 including the measurement error of the current sensors Si1 and Si2. Output from unit 73. As a result, it is possible to suppress the deterioration of the controllability of the motor M due to the influence of the measurement error of the current sensors Si1 and Si2.

Further, when the difference between the pulsation amplitude value Aω included in the rotation speed ω2 and the target amplitude value Aω0 is relatively large, and when the rotation speed ω2 is larger than the rotation speed ω22, the weights w2 and w3 are 1 or abbreviated, respectively. Since it becomes 1, the weight w1 which is the multiplication value of the weight w2 and the weight w3 becomes 1 or substantially 1, and the rotation speed ω1 or the rotation speed close to the rotation speed ω1 is output from the third output unit 73 as the rotation speed ω3. Will be done. In this way, when the pulsation amplitude value Aω and the rotation number ω2 included in the rotation number ω2 are relatively large, the amplitude value Aω may be relatively large due to the influence of the quantization error included in the position θ. Is higher, so the rotation number ω1 that is not affected by the quantization error included in the position θ is output as the rotation number ω3 from the third calculation unit 73.

According to the second embodiment, the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current flowing through the motor M, or the pulsation amplitude value Av included in the voltage command value is relatively large. In some cases, and when the rotation speed ω2 is relatively large, that is, there is a high possibility that the amplitude value of the pulsation is relatively large due to the influence of the quantization error included in the position θ, and the rotation speed ω2 is high. In a relatively large case, the rotation number ω1 that is not affected by the quantization error included in the position θ can be set as the rotation number ω3. As a result, the drive of the motor M can be controlled by the rotation speed ω3 that is not affected by the quantization error included in the position θ, so that the current flowing through the motor M and the pulsating amplitude value included in the voltage command value can be suppressed. It is possible to suppress the torque ripple of the motor M, which cannot be suppressed when the switching between the sensor use control and the sensorless control is determined using only the rotation speed ω2 of the motor M.

Further, according to the second embodiment, among the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current flowing through the motor M, and the pulsation amplitude value Av included in the voltage command value. Compared to the case where the weight w1 is obtained from one amplitude value of, it is included in the position θ when it is more likely that the amplitude value of the pulsation is relatively large due to the influence of the quantization error included in the position θ. Since the rotation speed ω1 that is not affected by the quantization error can be set to the rotation speed ω3, the torque ripple of the motor M can be suppressed more accurately.

Further, according to the second embodiment, as in the first embodiment, when switching from the rotation speed ω2 to the rotation speed ω1 as the rotation speed ω3, the rotation speed ω2 may be gradually changed to the rotation speed ω1 by the weight w1. Or, when switching from the rotation speed ω1 to the rotation speed ω2 as the rotation speed ω3, the rotation speed ω1 can be gradually changed from the rotation speed ω2 to the rotation speed ω2 by the weight w1. Compared to the case of suddenly switching to ω1 or from the rotation speed ω1 to the rotation speed ω2, the fluctuation of the rotation speed ω3 due to the influence of the measurement error of the current sensors Si1 and Si2 can be suppressed, so that the fluctuation of the torque of the motor M is suppressed. be able to.

<Third Example>
FIG. 5 is a flowchart showing an example of the operation of the third calculation unit 73 in the third embodiment. Since step S33 shown in FIG. 5 is the same as step S13 shown in FIG. 3, the description of step S33 will be omitted.

First, in step S31, the third calculation unit 73 includes a pulsation amplitude value Aω included in the rotation speed ω2, a pulsation amplitude value Ai included in the current Iq, and a pulsation amplitude value included in the voltage command value Vq *. Two amplitude values of Av are calculated.

Next, in step S32, the third calculation unit 73 obtains the weight w1 from the amplitude value of each pulsation calculated in step S31.

<When obtaining the weight w1 from the amplitude value Aω and the amplitude value Ai>
First, the third calculation unit 73 obtains the weight w1 corresponding to the amplitude value Aω by using the information D1 or the PI control shown in the above equations 6, 7, and 8, and sets the obtained weight w1 as the weight wω. At the same time, the weight w1 corresponding to the amplitude value Ai is obtained by using the information D2 or the PI control shown in the above equations 6, 9, and 10, and the obtained weight w1 is set as the weight wi.

Next, the third calculation unit 73 uses the multiplication value of the weight wω and the weight wi as the weight w1 used in step S33.

<When obtaining the weight w1 from the amplitude value Aω and the amplitude value Av>
First, the third calculation unit 73 obtains the weight w1 corresponding to the amplitude value Aω by using the information D1 or the PI control shown in the above equations 6, 7, and 8, and sets the obtained weight w1 as the weight wω. At the same time, the weight w1 corresponding to the amplitude value Av is obtained by using the information D3 or the PI control shown in the above equations 6, 13, and 14, and the obtained weight w1 is used as the weight wv.

Next, the third calculation unit 73 uses the multiplication value of the weight wω and the weight wv as the weight w1 used in step S33.

<When obtaining the weight w1 from the amplitude value Ai and the amplitude value Av>
First, the third calculation unit 73 obtains the weight w1 corresponding to the amplitude value Ai using the information D2 or the PI control shown in the above equations 6, 9, and 10, and sets the obtained weight w1 as the weight wi. At the same time, the weight w1 corresponding to the amplitude value Av is obtained by using the information D3 or the PI control shown in the above equations 6, 13, and 14, and the obtained weight w1 is used as the weight wv.

Next, the third calculation unit 73 uses the multiplication value of the weight wi and the weight wv as the weight w1 used in step S33.

For example, when the amplitude value Aω is larger than the amplitude value Aω2 and the amplitude value Ai is smaller than the amplitude value Ai1, the weight wi becomes zero even though the weight wω is 1, so the weight wω and the weight. The weight w1 which is a multiplication value with wi becomes zero, and the rotation speed ω2 is output from the third output unit 73 as the rotation speed ω3. In this way, when the amplitude value of one of the two amplitude values is relatively large and the amplitude value of the other is relatively small, the amplitude value of one is relatively large due to the influence of the quantization error included in the position θ. Since it is unlikely that the rotation speed is ω2, the rotation speed ω2 close to the actual rotation speed is output from the third calculation unit 73 as the rotation speed ω3. As a result, it is possible to suppress the deterioration of the controllability of the motor M due to the influence of the measurement error of the current sensors Si1 and Si2.

Further, when the amplitude value Aω is larger than the threshold value Aω2 and the amplitude value Ai is larger than the amplitude value Ai2, the weight wω and the weight wi are 1 respectively, so that the weight is a multiplication value of the weight wω and the weight wi. w1 becomes 1, and the rotation speed ω1 is output from the third output unit 73 as the rotation speed ω3. In this way, when the two amplitude values are relatively large, it is highly possible that the two amplitude values are relatively large due to the influence of the quantization error included in the position θ, so that they are included in the position θ. The rotation speed ω1 that is not affected by the quantization error is output as the rotation speed ω3 from the third calculation unit 73.

According to the third embodiment, two of the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current flowing through the motor M, and the pulsation amplitude value Av included in the voltage command value. When one of the amplitude values is relatively large, that is, when the amplitude value of the pulsation is likely to be relatively large due to the influence of the quantization error included in the position θ, the quantization error included in the position θ The rotation number ω1 having no influence can be set to the rotation number ω3. As a result, the drive of the motor M can be controlled by the rotation speed ω3 that is not affected by the quantization error included in the position θ, so that the current flowing through the motor M and the pulsating amplitude value included in the voltage command value can be suppressed. It is possible to suppress the torque ripple of the motor M, which cannot be suppressed when the switching between the sensor use control and the sensorless control is determined using only the rotation speed ω2 of the motor M.

Further, according to the third embodiment, among the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current flowing through the motor M, and the pulsation amplitude value Av included in the voltage command value. Compared to the case where the weight w1 is calculated from one amplitude value of, it is included in the position θ when it is more likely that the amplitude value of the pulsation is relatively large due to the influence of the quantization error included in the position θ. Since the rotation speed ω1 that is not affected by the quantization error can be set to the rotation speed ω3, the torque ripple of the motor M can be suppressed more accurately.

Further, according to the third embodiment, when switching from the rotation speed ω2 to the rotation speed ω1 as the rotation speed ω3, the weight w1 may gradually change the rotation speed ω2 to the rotation speed ω1. Or, when switching from the rotation speed ω1 to the rotation speed ω2 as the rotation speed ω3, the rotation speed ω1 can be gradually changed from the rotation speed ω2 to the rotation speed ω2 by the weight w1. Compared to the case of suddenly switching to ω1 or from the rotation speed ω1 to the rotation speed ω2, the fluctuation of the rotation speed ω3 due to the influence of the measurement error of the current sensors Si1 and Si2 can be suppressed, so that the fluctuation of the torque of the motor M is suppressed. be able to.

<Fourth Example>
FIG. 6 is a flowchart showing an example of the operation of the third calculation unit 73 in the fourth embodiment. Since step S43 shown in FIG. 6 is the same as step S13 shown in FIG. 3, the description of step S43 will be omitted.

First, in step S41, the third calculation unit 73 includes the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current Iq, and the pulsation amplitude value included in the voltage command value Vq *. Calculate Av.

Next, in step S42, the third calculation unit 73 calculates the weight w1 from the amplitude value of each pulsation calculated in step S41.

For example, first, the third calculation unit 73 obtains the weight wω from the amplitude value Aω, obtains the weight wi from the amplitude value Ai, and calculates the weight wv from the amplitude value Av. The weights wω, wi, and wv may be calculated using the information D1, D2, and D3 stored in the storage unit 4, or may be calculated by PI control.

Next, the third calculation unit 73 uses the multiplication value of the weight wω, the weight wi, and the weight wv as the weight w1 used in step S43.

For example, when the amplitude value Aω is larger than the amplitude value Aω2, the amplitude value Ai is smaller than the amplitude value Ai1, and the amplitude value Av is smaller than the amplitude value Av1, the weight wω is 1. However, since the weights wi and wv become zero, the weight w1 which is the multiplication value of the weight wω, the weight wi, and the weight ωv becomes zero, and the rotation number ω2 is output from the third output unit 73 as the rotation number ω3. Will be done. Thus, when at least one of the three amplitude values is relatively large but the remaining amplitude values are relatively small, at least one amplitude is affected by the quantization error included in the position θ. Since it is unlikely that the value is relatively large, the rotation speed ω2 close to the actual rotation speed is output from the third calculation unit 73 as the rotation speed ω3. As a result, it is possible to suppress the deterioration of the controllability of the motor M due to the influence of the measurement error of the current sensors Si1 and Si2.

Further, when the amplitude value Aω is larger than the amplitude value Aω2, the amplitude value Ai is larger than the amplitude value Ai2, and the amplitude value Av is larger than the amplitude value Av2, the weight wω, the weight wi, and the weight wv. Is 1, so that the weight w1 which is the multiplication value of the weight wω, the weight wi, and the weight wv becomes 1, and the rotation speed ω1 is output from the third output unit 73 as the rotation speed ω3. In this way, when each of the three amplitude values is relatively large, there is a high possibility that the three amplitude values are relatively large due to the influence of the quantization error included in the position θ, so that the quantization included in the position θ is included. The rotation speed ω1 that is not affected by the error is output as the rotation speed ω3 from the third calculation unit 73.

According to the fourth embodiment, the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current flowing through the motor M, and the pulsation amplitude value Av included in the voltage command value are relatively high. When it is large, that is, when there is a high possibility that the amplitude value of the pulsation is relatively large due to the influence of the quantization error included in the position θ, the rotation speed ω1 which is not affected by the quantization error included in the position θ Can be set to the rotation speed ω3. As a result, the drive of the motor M can be controlled by the rotation speed ω3 that is not affected by the quantization error included in the position θ, so that the current flowing through the motor M and the pulsating amplitude value included in the voltage command value can be suppressed. It is possible to suppress the torque ripple of the motor M, which cannot be suppressed when the switching between the sensor use control and the sensorless control is determined using only the rotation speed ω2 of the motor M.

Further, according to the fourth embodiment, among the pulsation amplitude value Aω included in the rotation speed ω2, the pulsation amplitude value Ai included in the current flowing through the motor M, and the pulsation amplitude value Av included in the voltage command value. In the case where it is more likely that the amplitude value of the pulsation is relatively large due to the influence of the quantization error included in the position θ, as compared with the case where the weight w1 is obtained from one amplitude value or two amplitude values of. Since the rotation speed ω1 that is not affected by the quantization error included in the position θ can be set to the rotation speed ω3, the torque ripple of the motor M can be suppressed more accurately.

Further, according to the fourth embodiment, when switching from the rotation speed ω2 to the rotation speed ω1 as the rotation speed ω3, the weight w1 may gradually change the rotation speed ω2 to the rotation speed ω1. Or, when switching from the rotation speed ω1 to the rotation speed ω2 as the rotation speed ω3, the rotation speed ω1 can be gradually changed from the rotation speed ω2 to the rotation speed ω2 by the weight w1. Compared to the case of suddenly switching to ω1 or from the rotation speed ω1 to the rotation speed ω2, the fluctuation of the rotation speed ω3 due to the influence of the measurement error of the current sensors Si1 and Si2 can be suppressed, so that the fluctuation of the torque of the motor M is suppressed. be able to.

The present invention is not limited to the above embodiments, and various improvements and changes can be made without departing from the gist of the present invention.

1 Control device 2 Inverter circuit 3 Control circuit 4 Storage unit 5 Drive circuit 6 Calculation unit 8 Subtraction unit 9 Torque control unit 10 Torque / current command value conversion unit 11 Coordinate conversion unit 12 Subtraction unit 13 Subtraction unit 14 Current control unit 15 Coordinate conversion Part 71 First calculation unit 72 Second calculation unit 73 Third calculation unit

Claims (6)

A first calculation unit that calculates the first rotation speed of the motor based on the current flowing through the motor, and
A second calculation unit that calculates the second rotation speed of the motor according to the position of the rotor of the motor, and
The third by the first weight, the first rotation speed, and the second rotation speed, which is the ratio of the first rotation speed and the second rotation speed to be reflected in the third rotation speed. A third calculation unit that calculates the number of revolutions and
A command value output unit that outputs a voltage command value based on the rotation speed difference between the third rotation speed and the rotation speed command value,
A drive circuit that outputs a drive signal according to the comparison result between the voltage value of the carrier wave and the voltage command value, and
An inverter circuit that converts input DC power into AC power and drives the motor by turning the switching element on and off by the drive signal.
Equipped with
The third calculation unit is at least one of the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value. A motor control device, characterized in that the first weight is obtained from one amplitude value. The motor control device according to claim 1.
The amplitude value of the pulsation included in the second rotation speed, the amplitude value of the pulsation included in the current flowing through the motor, and the amplitude value of the pulsation included in the voltage command value, and the first amplitude value. Equipped with a storage unit that stores information indicating the correspondence with the weight of
The third calculation unit is included in the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the voltage command value with reference to the information. A motor control device for obtaining the first weight corresponding to at least one amplitude value of a pulsation amplitude value. The motor control device according to claim 1.
The third calculation unit is at least one of the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value. The first weight is obtained by PI control so that the one amplitude value becomes the target amplitude value which is the at least one amplitude value when the amplitude value of the torque ripple of the motor is equal to or less than the allowable value. Motor control device. The motor control device according to claim 1.
The third calculation unit is
The second weight is based on at least one amplitude value of the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value. And the third weight is obtained from the second rotation speed.
A motor control device, characterized in that the multiplication value of the second weight and the third weight is the first weight. The motor control device according to claim 4.
A storage unit for storing information indicating a correspondence relationship between the second rotation speed and the third weight is provided.
The third calculation unit is
At least one amplitude value of the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value is the motor. The second weight is obtained by PI control so that the target amplitude value, which is the at least one amplitude value when the amplitude value of the torque ripple is equal to or less than the allowable value, is obtained.
With reference to the information, the third weight corresponding to the second rotation speed is obtained.
A motor control device, characterized in that the multiplication value of the second weight and the third weight is the first weight. The motor control device according to claim 1.
The third calculation unit is based on the pulsation amplitude value included in the second rotation speed, the pulsation amplitude value included in the current flowing through the motor, and the pulsation amplitude value included in the voltage command value. A motor control device characterized in that a weight of 1 is obtained.

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