Motor control device, motor control method and program

Abstract

A motor control device and the like are provided that are capable of vector control of a motor without using a sensor for detecting phase current. [Solution] The motor includes a control unit that applies an applied voltage value corresponding to the electrical angle to the motor drive circuit based on feedback control of the d-axis current and q-axis current; an acquisition unit that acquires the electrical angular velocity and applied voltage value of the motor whose rotation is controlled by the control unit; and a calculation unit that calculates phase current values ​​of the motor windings based on the electrical angular velocity and applied voltage value acquired by the acquisition unit and the resistance value and inductance value of the motor windings, and the control unit performs feedback control using the phase current values ​​calculated by the calculation unit.

Description

[Technical Field]

[0001] The present invention relates to a motor control device, a motor control method, and a program. [Background technology]

[0002] There is known a technique for controlling the rotation of a motor using vector control of a phase current (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6136803 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in general, when vector control is used, a sensor is required to detect the phase current that is the object of control, which poses a problem of, for example, increasing costs.

[0005] The present invention has been made to solve the above problems, and has an object to provide a motor control device etc. that is capable of vector control of a motor without using a sensor for detecting phase currents. [Means for solving the problem]

[0006] In order to solve the above problem, one aspect of the present invention is to a control unit that applies an applied voltage value corresponding to an electrical angle to a drive circuit of the motor based on feedback control of the d-axis current and the q-axis current; an acquisition unit that acquires the electrical angular velocity of the motor whose rotation is controlled by the control unit and the applied voltage value; a calculation unit that calculates a phase current value of the motor winding based on the electrical angular velocity and the applied voltage value acquired by the acquisition unit, and a resistance value and an inductance value of the motor winding; Equipped with The motor control device provides a motor control device in which the control unit executes feedback control using the phase current value calculated by the calculation unit. [Effects of the Invention]

[0007] According to the present invention, vector control of the motor is possible without using a sensor for detecting phase currents. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a configuration of a motor control device according to an embodiment of the present invention. [Figure 2] 1 is a diagram illustrating an example of the configuration of a motor device to which a motor control device according to an embodiment of the present invention is applied; [Figure 3] FIG. 2 is a diagram illustrating a configuration example of a drive circuit. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the configuration of a motor control device of this embodiment, FIG. 2 is a diagram showing an example configuration of a motor device to which the motor control device of this embodiment is applied, and FIG. 3 is a diagram showing an example configuration of a drive circuit.

[0010] As shown in FIG. 1, the motor control device 100 of this embodiment includes a control unit 101 that applies an applied voltage value corresponding to an electrical angle to a drive circuit 10 that drives a motor M based on feedback control of a d-axis current and a q-axis current; an acquisition unit 102 that acquires the electrical angular velocity and applied voltage value of the motor M, whose rotation is controlled by the control unit 101; and a calculation unit 103 that calculates phase current values ​​of the motor windings based on the electrical angular velocity and applied voltage value acquired by the acquisition unit 102, and the resistance and inductance values ​​of the motor windings.

[0011] Furthermore, the motor control device 100 of this embodiment includes a correction unit 104 that corrects the resistance value input to the calculation unit 103 in accordance with the temperature of the motor windings.

[0012] 2, the motor device includes a three-phase brushless motor M, a drive circuit 10 that drives the brushless motor M, a feedback control unit 20, a drive signal generation unit 30, and an angle detection unit 40 that detects the electrical angle of the brushless motor M. The feedback control unit 20 includes a three-phase to two-axis conversion unit 21, a PI (proportional-integral) calculation unit 22, and a two-axis to three-phase conversion unit 23.

[0013] The motor device also includes a current calculation unit 50, an angular velocity calculation unit 41, and a storage unit 60.

[0014] 3, the drive circuit 10 is configured as a circuit in which a pair of semiconductor switches SU1 and SU2, a pair of semiconductor switches SV1 and SV2, and a pair of semiconductor switches SW1 and SW2 corresponding to the U phase, V phase, and W phase are respectively connected in series between ground and a power supply line L. Furthermore, the U phase, V phase, and W phase terminals of the brushless motor M are connected to the midpoints of the pair of semiconductor switches SU1 and SU2, the semiconductor switches SV1 and SV2, and the semiconductor switches SW1 and SW2, respectively. Pulse width modulated signals, which will be described later, are input to the pair of semiconductor switches SU1 and SU2, the pair of semiconductor switches SV1 and SV2, and the pair of semiconductor switches SW1 and SW2 as drive signals. A three-phase applied voltage is output to the brushless motor M by switching operations in accordance with the drive signals in the pair of semiconductor switches SU1 and SU2, the pair of semiconductor switches SV1 and SV2, and the pair of semiconductor switches SW1 and SW2.

[0015] Next, an operation relating to feedback control (vector control) of the motor M by the motor device will be described.

[0016] The three-phase-two-axis conversion unit 21 converts the U-phase current value Iu, the V-phase current value Iv, and the W-phase current value Iw calculated by the current calculation unit 50 into a q-axis current value and a d-axis current value based on the electrical angle θ of the brushless motor M acquired by the angle detection unit 40.

[0017] The PI calculation unit 22 performs PI calculation to output a q-axis voltage value and a d-axis voltage value that cause the q-axis current value and the d-axis current value input from the 3-phase-to-2-axis conversion unit 21 to follow the target q-axis current value and the target d-axis current value.

[0018] The 2-axis to 3-phase conversion unit 23 converts the q-axis voltage value and d-axis voltage value input from the PI calculation unit 22 into applied voltage values ​​(duty values) of the three phases U, V, and W based on the electrical angle θ of the brushless motor M acquired by the angle detection unit 52.

[0019] The drive signal generator 30 generates a drive signal corresponding to the applied voltage value (duty value) input from the two-axis-to-three-phase converter 23, and outputs the generated drive signal to the drive circuit 10.

[0020] The drive circuit 10 performs the above switching operation in response to the drive signal from the drive signal generating unit 30, and outputs to the brushless motor M a three-phase applied voltage in accordance with the applied voltage value (duty value).

[0021] Next, a description will be given of the operation of the current calculation unit 50. As described above, the current calculation unit 50 calculates the U-phase current value Iu, the V-phase current value Iv, and the W-phase current value Iw.

[0022] 2, the current calculation unit 50 acquires the electrical angle θ of the feedback-controlled motor M from the angle detection unit 40. Furthermore, as a function of the acquisition unit 102 (FIG. 1), the current calculation unit 50 acquires the electrical angular velocity ωe of the feedback-controlled motor M from the angular velocity calculation unit 41. Here, the angular velocity calculation unit 41 calculates the electrical angular velocity ωe based on the electrical angle θ acquired from the angle detection unit 40. Furthermore, as a function of the acquisition unit 102 (FIG. 1), the current calculation unit 50 acquires the applied voltage value (duty value) to the feedback-controlled motor M from the drive signal generation unit 30.

[0023] As a function of calculation unit 103, current calculation unit 50 calculates U-phase current value Iu, V-phase current value Iv, and W-phase current value Iw of the motor windings based on the acquired electrical angular velocity and applied voltage value, and the resistance and inductance values ​​of the motor windings. Specifically, the U-phase current value Iu can be calculated by solving equation (1) relating to the voltage of the U-phase motor winding for the U-phase current value Iu of the motor windings.

[0024]

number

[0025] Here, the resistance value R and inductance value L of the motor winding and the induced voltage constant Ke (Keu, Kev, Kew) can be stored in the memory unit 60, and the current calculation unit 50 can acquire the resistance value R, the inductance value L and the induced voltage constant Ke from the memory unit 60.

[0026] Furthermore, as a function of the correction unit 104, the current calculation unit 50 can correct the resistance value R of the motor windings acquired from the storage unit 60 in accordance with the temperature of the motor windings. Here, the resistance value R of the motor windings is corrected, for example, based on a table showing the relationship between the resistance value R and temperature or based on a correction formula showing this relationship. The table or correction formula can be stored in the storage unit 60, for example. The correction to the resistance value R of the motor windings is reflected in the calculated values ​​of the U-phase current value Iu, the V-phase current value Iv, and the W-phase current value Iw. The temperature of the motor windings (winding temperature) can be detected or estimated, for example, by a temperature sensor 70 (FIG. 2) attached to the motor M. By correcting the resistance value R of the motor windings in this way, calculation errors due to fluctuations in the resistance value R with temperature can be reduced. Furthermore, the inductance value L may also be corrected in accordance with the temperature of the motor windings, similar to the resistance value R. In this case, calculation errors due to fluctuations in the inductance value L with temperature can be reduced.

[0027] As described above, according to this embodiment, the U-phase current value Iu, the V-phase current value Iv, and the W-phase current value Iw are calculated, so sensors for detecting the phase currents are not required.

[0028] Generally, vector control requires sensing of phase currents to control the vector of the phase currents flowing through the motor windings. However, using Hall sensors to detect currents increases costs. Furthermore, when using a shunt method for current detection, the current detection range is limited, and calculations are required to calculate the current value of one phase from the current values ​​of other phases. Furthermore, the phase switching of pulse width modulation is required, which can cause problems such as noise and vibration during the switching.

[0029] In contrast, according to this embodiment, a sensor for detecting the phase current is not required, which reduces the cost and size of the device. Furthermore, since sensor failure does not occur, the reliability of the device can be improved. Furthermore, the power loss that occurs when a shunt-type current detection method is used can be avoided, resulting in a highly efficient motor control device.

[0030] The following additional notes are provided regarding the above-described embodiments of the present invention.

[0031] [Appendix 1] a control unit (101) that applies an applied voltage value corresponding to an electrical angle to a motor drive circuit (10) based on feedback control of a d-axis current and a q-axis current; an acquisition unit (102) that acquires the electrical angular velocity of the motor whose rotation is controlled by the control unit and the applied voltage value; a calculation unit (103) that calculates a phase current value of the motor winding based on the electrical angular velocity and the applied voltage value acquired by the acquisition unit, and a resistance value and an inductance value of the motor winding; Equipped with The control unit performs feedback control using the phase current value calculated by the calculation unit.

[0032] According to the configuration described in Supplementary Note 1, since the phase current value is calculated, a sensor for detecting the phase current is not required.

[0033] [Appendix 2] 2. The motor control device according to claim 1, further comprising: a correction unit (104) that corrects the resistance value input to the calculation unit in accordance with a temperature of the motor winding.

[0034] According to the configuration described in Supplementary Note 2, the resistance value of the motor windings is corrected in accordance with the temperature of the motor windings, thereby suppressing calculation errors caused by fluctuations in the motor windings due to temperature changes.

[0035] [Appendix 3] a control step of applying an applied voltage value according to an electrical angle to a drive circuit of the motor based on feedback control of the d-axis current and the q-axis current; an acquiring step of acquiring an electrical angular velocity of the motor whose rotation is controlled by the control step and the applied voltage value; a calculating step of calculating a phase current value of the motor winding based on the electrical angular velocity and the applied voltage value acquired in the acquiring step, and a resistance value and an inductance value of the motor winding; Equipped with In the control step, feedback control is performed using the phase current values ​​calculated in the calculation step.

[0036] According to the configuration described in Supplementary Note 3, since the phase current value is calculated, a sensor for detecting the phase current is not required.

[0037] [Appendix 4] On the computer, a control step of applying an applied voltage value according to an electrical angle to a drive circuit of the motor based on feedback control of the d-axis current and the q-axis current; an acquiring step of acquiring an electrical angular velocity of the motor whose rotation is controlled by the control step and the applied voltage value; a calculating step of calculating a phase current value of the motor winding based on the electrical angular velocity and the applied voltage value acquired in the acquiring step, and a resistance value and an inductance value of the motor winding; Equipped with a control step of controlling a motor by using the phase current value calculated in the calculation step;

[0038] According to the configuration described in Supplementary Note 4, since the phase current value is calculated, a sensor for detecting the phase current is not required. [Explanation of symbols]

[0039] 10. Drive circuit 20 Feedback control section 50 Current calculation section 101 Control section 102 Acquisition Department 103 Calculation Unit 104 Correction unit 100 Motor control device

Claims

1. a control unit that applies an applied voltage value corresponding to an electrical angle to a drive circuit of the motor based on feedback control of the d-axis current and the q-axis current; an acquisition unit that acquires the electrical angular velocity of the motor whose rotation is controlled by the control unit and the applied voltage value; a calculation unit that calculates a phase current value of the motor winding based on the electrical angular velocity and the applied voltage value acquired by the acquisition unit, and a resistance value and an inductance value of the motor winding; Equipped with The control unit performs feedback control using the phase current value calculated by the calculation unit.

2. The motor control device according to claim 1 , further comprising a correction unit that corrects the resistance value input to the calculation unit in accordance with a temperature of the motor winding.

3. a control step of applying an applied voltage value according to an electrical angle to a drive circuit of the motor based on feedback control of the d-axis current and the q-axis current; an acquiring step of acquiring an electrical angular velocity of the motor whose rotation is controlled by the control step and the applied voltage value; a calculating step of calculating a phase current value of the motor winding based on the electrical angular velocity and the applied voltage value acquired in the acquiring step, and a resistance value and an inductance value of the motor winding; Equipped with In the control step, feedback control is performed using the phase current values ​​calculated in the calculation step.

4. On the computer, a control step of applying an applied voltage value according to an electrical angle to a drive circuit of the motor based on feedback control of the d-axis current and the q-axis current; an acquiring step of acquiring an electrical angular velocity of the motor whose rotation is controlled by the control step and the applied voltage value; a calculating step of calculating a phase current value of the motor winding based on the electrical angular velocity and the applied voltage value acquired in the acquiring step, and a resistance value and an inductance value of the motor winding; Equipped with a control step of controlling a motor by using the phase current value calculated in the calculation step;

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