Motor control device

Abstract

To suppress destabilization of motor control without reducing a control response of an output voltage amplitude in a voltage saturation region.SOLUTION: In a motor control device 100a, a voltage command value generator 14 generates a voltage command value of a motor on the basis of a speed error between a speed command value and a speed of a motor M, and a control switching determination section 15 determines whether or not a control region of the motor M is in a voltage saturation region. A non-interference correction value calculator 14b7A calculates a correction value for non-interfering an interference caused by an induction voltage of the motor M and if it is determined by the control switching determination section 15 that the control region is in the voltage saturation region, the voltage command value generator 14 generates a voltage amplitude of an output voltage applied to the motor M and a voltage phase of the output voltage applied to the motor M and calculates a voltage command value which is corrected by the correction value.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a motor control device. [Background technology]

[0002] There is a technology that uses different motor control methods between a region where the output voltage of a motor control device does not saturate (hereinafter sometimes referred to as the "normal region") and a region that includes the vicinity of the limit value of the output voltage of the motor control device and where the output voltage of the motor control device saturates (hereinafter sometimes referred to as the "voltage saturation region"). For example, there is a known technology that performs MTPA (Maximum Torque Per Ampere) control in the normal region, which maximizes the motor's output torque relative to the current, while controlling the amplitude (hereinafter sometimes referred to as "output voltage amplitude") and phase of the motor's output voltage in the voltage saturation region (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-125898 [Patent Document 2] Japanese Patent Application Publication No. 2017-158415 Summary of the Invention [Problem to be solved by the invention]

[0004] In such motor control devices, when the motor control method is switched, discontinuities in motor control before and after the switch can cause vibrations and noise in the motor. The vibrations and noise generated in the motor when the motor control method is switched is sometimes called "switching shock." When the region in the voltage saturation region where the voltage command value is maintained at the output limit value is defined as the flux-weakening region, a known motor control technique, for example, adjusts the output voltage amplitude so that the current vector moves along the MTPA control curve in the region between the normal control region and the flux-weakening region in order to reduce switching shock (Patent Document 2).

[0005] In response to this, the inventors of the present application discovered that in the voltage saturation region, where the output voltage amplitude is adjusted so that the current vector moves along the MTPA control curve, a phenomenon in which the current vector oscillates on the MTPA control curve may occur when, for example, the motor winding resistance or inductance is small.To avoid this phenomenon, it is conceivable to reduce the control response of the output voltage amplitude in the voltage saturation region.

[0006] However, when the motor's induced voltage changes as the motor's rotation speed changes, the responsiveness of the output voltage amplitude adjustment is impaired due to interference with the output voltage amplitude adjustment by the motor's induced voltage (hereinafter sometimes referred to as "induced voltage interference"), causing the current vector to deviate from the MTPA control curve, resulting in a deterioration in motor control efficiency.

[0007] Therefore, the present disclosure proposes a technique that can suppress instability in motor control without reducing the control response of the output voltage amplitude in the voltage saturation region. [Means for solving the problem]

[0008] The motor control device disclosed herein includes a voltage command value generator, a control switch determination unit, and a decoupling correction value calculator. The voltage command value generator generates a voltage command value for the motor based on a speed error between a speed command value and the speed of the motor. The control switch determination unit determines whether the control region of the motor is in a voltage saturation region. The decoupling correction value calculator calculates a correction value that decouplings interference due to an induced voltage of the motor. When the control switch determination unit determines that the control region is in the voltage saturation region, the voltage command value generator generates a voltage amplitude and a voltage phase of an output voltage applied to the motor, and calculates a voltage command value corrected using the correction value. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to suppress instability in motor control without reducing the control response of the output voltage amplitude in the voltage saturation region. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram illustrating a configuration example of a motor control device according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a diagram illustrating a configuration example of a control switching determination unit according to the first embodiment of the present disclosure. [Figure 3] FIG. 3 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to the first embodiment of the present disclosure. [Figure 4] FIG. 4 is a diagram illustrating an example of the operation of the motor control device according to the first embodiment of the present disclosure. [Figure 5] FIG. 5 is a diagram illustrating an example of the operation of the current command value calculator according to the first embodiment of the present disclosure. [Figure 6] FIG. 6 is a diagram illustrating an example of the operation of the current command value calculator according to the first embodiment of the present disclosure. [Figure 7] FIG. 7 is a diagram illustrating a configuration example of the normal control region voltage command value generator according to the first embodiment of the present disclosure. [Figure 8] FIG. 8 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to the second embodiment of the present disclosure. [Figure 9] FIG. 9 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to the third embodiment of the present disclosure. [Figure 10] FIG. 10 is a diagram illustrating a configuration example of a motor control device according to a fourth embodiment of the present disclosure. [Figure 11] FIG. 11 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to a fourth embodiment of the present disclosure. [Figure 12] FIG. 12 is a diagram illustrating a configuration example of a normal control region voltage command value generator according to a fourth embodiment of the present disclosure. [Figure 13] FIG. 13 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to a fifth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following embodiments, the same components are designated by the same reference numerals.

[0012] [Example 1] <Motor control device configuration> FIG. 1 is a diagram illustrating an example configuration of a motor control device according to a first embodiment of the present disclosure. In FIG. 1, a motor control device 100a includes a subtractor 11, a speed controller 12, a voltage command value generator 14, a control switching determination unit 15, a dq / u, v, w converter 23, a PWM (Pulse Width Modulation) modulator 24, and an IPM (Intelligent Power Module) 25. The IPM 25 is connected to a motor M. An example of the motor M is a permanent magnet synchronous motor (PMSM).

[0013] The motor control device 100a also includes a shunt resistor 26, one of current sensors 27a and 27b, and a 3φ current calculator .

[0014] The motor control device 100 a also includes a u, v, w / dq converter 29 , an axis error calculator 30 , a PLL (Phase Locked Loop) controller 31 , a position estimator 32 , and a 1 / Pn processor 33 .

[0015] The voltage command value generator 14 includes a normal control region voltage command value generator 14a-1, a voltage saturation region voltage command value generator 14b-1, a switch SW1, and a switch SW2. The switch SW1 includes contacts 14c-1, 14c-2, and 14c-3. The switch SW2 includes contacts 14c-4, 14c-5, and 14c-6.

[0016] The subtractor 11 subtracts the mechanical angular velocity command value ωm input to the motor control device 100a from an external device (for example, a higher-level controller) outside the motor control device 100a. *The angular velocity error Δωm is calculated by subtracting the mechanical angle estimated angular velocity ωm, which is the current estimated angular velocity output from the 1 / Pn processor 33, from the angular velocity error Δωm, and the calculated angular velocity error Δωm is output to the velocity controller 12.

[0017] The speed controller 12 controls the torque command value T so that the angular speed error Δωm approaches zero, for example, according to equation (1) based on PI (Proportional Integral) control. * is generated, and the generated torque command value T * is output to the voltage command value generator 14. In equation (1), kp is the proportional gain of the PI control, and ki is the integral gain of the PI control.

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[0018] The voltage command value generator 14 calculates the torque command value T output from the speed controller 12 in each of the normal control region and the voltage saturation region. * Based on this, the d-axis voltage command value Vd * and q-axis voltage command value Vq * The generated d-axis voltage command value Vd * and q-axis voltage command value Vq * The voltage saturation region is a region where the output voltage amplitude Va saturates in the high rotation region of the motor M and flux-weakening control is performed. The normal control region is a region outside the voltage saturation region, where the motor M is controlled by varying the output voltage, and in the normal control region, maximum torque / current control, etc., is performed.

[0019] When the control switch determination unit 15 outputs a control signal CONTROL_TYPE: A (normal control), the voltage command value generator 14 connects the contact 14c-1 and the contact 14c-3 of the switch SW1 and also connects the contact 14c-4 and the contact 14c-6 of the switch SW2 to generate the d-axis voltage command value Vd * and q-axis voltage command value Vq *to the dq / u, v, w converter 23. On the other hand, when the control switching determination unit 15 outputs the control signal CONTROL_TYPE: B (voltage saturation control), the voltage command value generator 14 connects the contacts 14c-2 and 14c-3 of the switch SW1 and also connects the contacts 14c-5 and 14c-6 of the switch SW2, and outputs the d-axis voltage command value Vd * and q-axis voltage command value Vq * is output to the dq / u,v,w converter 23.

[0020] The control switching determination unit 15 determines whether the output voltage limit value Vdq_limit and the d-axis voltage command value Vd * and the q-axis voltage command value Vq * Based on this, the control switching determination unit 15 determines whether the current control region of the motor M is the normal control region or the voltage saturation region. If the control switching determination unit 15 determines that the current control region of the motor M is the normal control region, it outputs a control signal CONTROL_TYPE: A (normal control) to the voltage command value generator 14, and if the control switching determination unit 15 determines that the current control region of the motor M is the voltage saturation region, it outputs a control signal CONTROL_TYPE: B (voltage saturation control) to the voltage command value generator 14. The output voltage limit value Vdq_limit is obtained by converting a DC voltage Vdc supplied to the IPM 25 from outside the IPM 25 (for example, a power supply converter not shown) into a voltage value in a dq rotating coordinate system, which is the control system.

[0021] The dq / u,v,w converter 23 converts the two-phase d-axis voltage command value Vd * and q-axis voltage command value Vq * is calculated based on the electrical angle phase (dq axis phase) θe, which is the current rotor position output from the position estimator 32, as the U-phase output voltage command value Vu * , V-phase output voltage command value Vv * and W-phase output voltage command value Vw * Then, the dq / u,v,w converter 23 converts the U-phase output voltage command value Vu * , V-phase output voltage command value Vv * and W-phase output voltage command value Vw* is output to the PWM modulator 24.

[0022] The PWM modulator 24 outputs a U-phase output voltage command value Vu * , V-phase output voltage command value Vv * , W-phase output voltage command value Vw * and the PWM carrier signal, and outputs the generated six-phase PWM signals to the IPM 25.

[0023] Based on the six-phase PWM signal output from the PWM modulator 24, the IPM 25 converts the DC voltage Vdc supplied from outside the IPM 25 to generate AC voltages to be applied to the U phase, V phase, and W phase of the motor M, and applies each of the AC voltages to the U phase, V phase, and W phase of the motor 10.

[0024] When the bus current is detected by a single shunt method using shunt resistor 26, 3φ current calculator 28 calculates the U-phase current value Iu, the V-phase current value Iv, and the W-phase current value Iw of motor M based on the six-phase PWM switching information output from PWM modulator 24 and the detected bus current. Alternatively, when the U-phase current and the V-phase current are detected by current sensors 27a and 27b, 3φ current calculator 28 calculates the remaining W-phase current value Iw based on Kirchhoff's law of "Iu + Iv + Iw = 0." 3φ current calculator 28 outputs the calculated phase current values ​​Iu, Iv, and Iw of each phase to u, v, w / dq converter 29. In this way, shunt resistor 26 and 3φ current calculator 28 correspond to current detectors that detect the U-phase current value Iu, the V-phase current value Iv, and the W-phase current value Iw. The U-phase current value Iu, the V-phase current value Iv, and the W-phase current value Iw correspond to the motor currents flowing through the motor M.

[0025] The u,v,w / dq converter 29 converts the three-phase U-phase current value Iu, V-phase current value Iv, and W-phase current value Iw output from the 3φ current calculator 28 into two-phase d-axis current Id and q-axis current Iq, based on the electrical angle phase θe indicating the current rotor position output from the position estimator 32. The u,v,w / dq converter 29 then outputs the d-axis current Id and q-axis current Iq to the voltage command value generator 14 and the axis error calculator 30.

[0026] The axis error calculator 30 calculates the d-axis voltage command value Vd * and q-axis voltage command value Vq * and calculates an axis error Δθ (the difference between the estimated rotation axis and the actual rotation axis) using the d-axis current Id and the q-axis current Iq output from the u,v,w / dq converter 29. The axis error calculator 30 then outputs the calculated axis error Δθ to the PLL controller 31.

[0027] The PLL controller 31 calculates the electrical angle estimated angular velocity ωe, which is the current estimated angular velocity, based on the axis error Δθ output from the axis error calculator 30, and outputs the calculated electrical angle estimated angular velocity ωe to the position estimator 32 and the 1 / Pn processor 33.

[0028] The position estimator 32 estimates the electrical angle phase θe based on the electrical angle estimated angular velocity ωe output from the PLL controller 31, and outputs the estimated electrical angle phase θe to the dq / u,v,w converter 23 and the u,v,w / dq converter 29.

[0029] The 1 / Pn processor 33 calculates a mechanical angle estimated angular velocity ωm by dividing the electrical angle estimated angular velocity ωe output from the PLL controller 31 by the number Pn of pole pairs of the motor M, and outputs the calculated mechanical angle estimated angular velocity ωm to the subtractor 11.

[0030] <Configuration of the control switching determination unit> 2 is a diagram illustrating a configuration example of a control switching determination unit according to the first embodiment of the present disclosure. In FIG. 2, the control switching determination unit 15 includes a voltage amplitude calculator 15a and a control switching determiner 15b, and determines whether the current control region of the motor is the normal control region or the voltage saturation region as follows.

[0031] The voltage amplitude calculator 15a calculates the d-axis voltage command value Vd * and q-axis voltage command value Vq * Based on this, the output voltage amplitude Va is calculated according to equation (2).

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[0032] The control switching determiner 15b compares the output voltage amplitude Va calculated by the voltage amplitude calculator 15a (or the peak value of the output voltage amplitude Va when the output voltage fluctuates) with the output voltage limit value Vdq_limit.

[0033] If the output voltage amplitude Va is less than the output voltage limit value Vdq_limit, the control switching determiner 15b determines that the current control region of the motor M is the normal control region, and outputs the control signal CONTROL_TYPE:A to the voltage command value generator 14.

[0034] On the other hand, if the output voltage amplitude Va is equal to or greater than the output voltage limit value Vdq_limit, the control switching determiner 15b determines that the current control region of the motor M is the voltage saturation region, and outputs the control signal CONTROL_TYPE:B to the voltage command value generator 14.

[0035] <Configuration of voltage saturation region voltage command value generator> Fig. 3 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to the first embodiment of the present disclosure. A voltage saturation region voltage command value generator 14b-1a illustrated in Fig. 3 corresponds to the voltage saturation region voltage command value generator 14b-1 illustrated in Fig. 1. In Fig. 3, the voltage saturation region voltage command value generator 14b-1a includes a voltage amplitude adjuster 14b1, an induced voltage command value calculator 14b2, a current command value calculator 14b3, a temporary voltage command value calculator 14b4, a voltage phase adjuster 14b5A, a voltage command value calculator 14b6, a decoupling correction value calculator 14b7A, and an adder 14b8.

[0036] Voltage amplitude regulator 14b1 generates a PI voltage command value Va_pi adjusted so that the current vector moves along the MTPA control curve, based on the d-axis current Id and the q-axis current Iq output from u,v,w / dq converter 29, and outputs the generated PI voltage command value Va_pi to adder 14b8. Details of the processing in voltage amplitude regulator 14b1 will be described later.

[0037] The decoupling correction value calculator 14b7A calculates a voltage amplitude decoupling correction value Va_ff for decoupling induced voltage interference, based on the electrical angle estimated angular velocity ωe output from the PLL controller 31 and the d-axis current Id and q-axis current Iq output from the u,v,w / dq converter 29, and outputs the calculated voltage amplitude decoupling correction value Va_ff to the adder 14b8. Details of the processing in the decoupling correction value calculator 14b7A will be described later.

[0038] The adder 14b8 adds the PI voltage command value Va_pi output from the voltage amplitude regulator 14b1 and the voltage amplitude decoupling correction value Va_ff output from the decoupling correction value calculator 14b7A to calculate the voltage amplitude command value Va_pi. * Calculate the voltage amplitude command value Va * to the induced voltage command value calculator 14b2 and the voltage command value calculator 14b6.

[0039] The induced voltage command value calculator 14b2 calculates a voltage amplitude command value Va based on the current d-axis current Id, the current q-axis current Iq, and the current electrical angle estimated angular velocity ωe in accordance with the motor model equations shown in Equations (3.1) and (3.2). * The induced voltage command value Vo based on * In addition, if there is no fluctuation in the motor current, equations (3.1) and (3.2) can be used as motor model equations that do not include the transient terms (p·Ld·Id, p·Lq·Iq). Below, the induced voltage command value Vo * The calculation details are shown below.

[0040] The voltage equations (d-axis voltage Vd, q-axis voltage Vq) of the PMSM, the theoretical formula for the output voltage amplitude Va, and the theoretical formula for the induced voltage Vo of the motor M are shown in equations (3.1) to (5). In equations (3.1) to (5), R is the winding resistance of the motor M, Ψa is the armature flux linkage of the motor M, Ld is the d-axis inductance of the motor M, and Lq is the q-axis inductance of the motor M.

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[0041] Furthermore, from equations (3.1) to (5), the voltage amplitude command value Va * and the induced voltage command value Vo * The equation relating these is expressed as equation (6). Therefore, the induced voltage command value calculator 14b2 calculates the induced voltage command value Vo according to equation (6). * Calculate the induced voltage command value Vo * to the current command value calculator 14b3. Similar to equations (3.1) and (3.2), equation (6) may be a motor model equation that does not include the transient terms (p·Ld·Id, p·Lq·Iq) when there is no fluctuation in the motor current.

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[0042] As shown in FIG. 4, the current command value calculator 14b3 calculates the torque command value T * The constant torque curve is the current locus where the induced voltage command value Vo * and the q-axis current command value Iq * and the d-axis current command value Id * 4 is a diagram illustrating an example of the operation of the motor control device according to the first embodiment of the present disclosure. The current command value calculator 14b3 calculates the calculated q-axis current command value Iq* and d-axis current command value Id * to the temporary voltage command value calculator 14b4.

[0043] The intersection of the constant torque curve and the constant induced voltage ellipse can be calculated using, for example, the motor torque equation shown in equation (7) and the induced voltage equation shown in equation (8).

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[0044] By eliminating the d-axis current Id from equations (7) and (8), a quartic equation related to the q-axis current Iq can be obtained as shown in equation (9), where ΔL=Ld−Lq.

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[0045] As a solution to the quartic equation shown in equation (9), for example, Newton's method or the like is used for the quartic equation shown in equation (9), and the torque command value T * The q-axis current command value Iq at the point where the constant torque curve, which is the current locus where the induced voltage Vo and the estimated electrical angle angular velocity ωe are constant, intersects with the constant induced voltage ellipse, which is the current locus where the induced voltage Vo and the estimated electrical angle angular velocity ωe are constant. * A solution equivalent to the following can be derived (see Figure 4).

[0046] The current command value calculator 14b3 calculates the q-axis current command value Iq * After calculating the induced voltage formula shown in formula (8), the q-axis current command value Iq is calculated according to formula (10), which is a transformation of formula (8) into a d-axis current formula. * Based on this, the d-axis current command value Id * Calculate.

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[0047] In equation (10), whether the sign associated with √ is positive or negative is determined by calculating the torque at the point where the constant induced voltage ellipse intersects with a line (hereinafter referred to as the "M-point boundary line") that is parallel to the Iq axis and passes through point M (-Ψa / Ld,0), which is the center of the constant induced voltage ellipse, and then calculating the torque at the point where the constant induced voltage ellipse intersects with the line (hereinafter referred to as the "M-point boundary torque T_M") and calculating the relationship between the M-point boundary torque T_M and the torque command value T * can be determined by comparing

[0048] The d-axis current command value Id * and q-axis current command value Iq * 5 and 6 are diagrams illustrating an example of the operation of the current command value calculator according to the first embodiment of the present disclosure.

[0049] The current command value calculator 14b3 first calculates the d-axis current Id_M on point M according to equation (11).

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[0050] Next, the current command value calculator 14b3 calculates the q-axis current Iq_M at the point where the boundary line at point M intersects with the constant induced voltage ellipse. The q-axis current Iq_M can be calculated by substituting the d-axis current Id_M at point M into equation (8), and is therefore calculated according to equation (12).

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[0051] Therefore, the current command value calculator 14b3 calculates the M-point boundary torque T_M according to equation (13).

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[0052] Then, the current command value calculator 14b3 calculates the torque command value T *Based on the magnitude relationship between the torque T_M on the boundary at point M, the d-axis current command value Id * The equation (14.1) contains the torque command value T * d-axis current command value Id when torque on the M-point boundary T_M * (See Figure 5) and the equation (14.2) shows the torque command value T * > d-axis current command value Id in case of torque T_M on the boundary of point M * (See Figure 6).

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[0053] The current command value calculator 14b3 calculates the d-axis current command value Id * and q-axis current command value Iq * to the temporary voltage command value calculator 14b4.

[0054] The temporary voltage command value calculator 14b4 calculates the electrical angle estimated angular velocity ωe and the d-axis current command value Id * and q-axis current command value Iq * Based on this, a tentative d-axis voltage command value Vd_m and a tentative q-axis voltage command value Vq_m are calculated in a feedforward manner in accordance with the motor model equations shown in equations (15.1) and (15.2). Note that, similar to equations (3.1) and (3.2), equations (15.1) and (15.2) may be motor model equations that do not include transient terms (p·Ld·Id, p·Lq·Iq) when there are no fluctuations in the motor current. The tentative voltage command value calculator 14b4 outputs the calculated tentative d-axis voltage command value Vd_m and tentative q-axis voltage command value Vq_m to the voltage phase regulator 14b5A.

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[0055] The voltage phase adjuster 14b5A adjusts the voltage phase command value δ based on the temporary d-axis voltage command value Vd_m and the temporary q-axis voltage command value Vq_m in accordance with the equation (16). * is adjusted, and the adjusted voltage phase command value δ *is output to the voltage command value calculator 14b6. In this way, the voltage phase command value δ * Torque command value T * By adjusting the feedforward in accordance with the voltage saturation voltage, it is possible to speed up the torque response in the voltage saturation region. Therefore, for example, it is possible to improve the vibration damping efficiency when performing vibration damping control of the motor M in the voltage saturation region, and to suppress sudden speed changes of the motor M due to disturbances.

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[0056] The voltage command value calculator 14b6 calculates the adjusted voltage phase command value δ * and voltage amplitude command value Va * Based on this, the d-axis voltage command value Vd is calculated by converting the polar coordinates into Cartesian coordinates according to equations (17.1) and (17.2). * and q-axis voltage command value Vq * Calculate.

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[0057] <Voltage amplitude command value Va * Generation of > Next, the voltage amplitude command value Va is calculated by the voltage amplitude adjuster 14b1, the non-interference correction value calculator 14b7A, and the adder 14b8. * The generation of is explained below.

[0058] The voltage amplitude regulator 14b1 adjusts the d-axis current Id_mtpa on the MTPA control curve based on the current q-axis current Iq in accordance with equation (18) so that the current current vector moves on the MTPA control curve. * Calculate the d-axis current Id_mtpa on the MTPA control curve according to equation (19). *and the current d-axis current Id. Voltage amplitude regulator 14b1 outputs the calculated PI voltage command value Va_pi to adder 14b8. In equations (18) and (19), Ψa is the armature flux linkage of motor M, Ld is the d-axis inductance of motor M, Lq is the q-axis inductance of motor M, kp is the proportional gain in PI control, and ki is the integral gain in PI control.

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[0059] On the other hand, the decoupling correction value calculator 14b7A calculates a d-axis decoupling correction value Vd_ff and a q-axis decoupling correction value Vq_ff for decoupling induced voltage interference according to equations (20) and (21).Then, the decoupling correction value calculator 14b7A calculates a composite induced voltage vector amplitude from the d-axis decoupling correction value Vd_ff and the q-axis decoupling correction value Vq_ff according to equation (22), and outputs the calculated composite induced voltage vector amplitude to the adder 14b8 as a voltage amplitude decoupling correction value Va_ff.

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[0060] The adder 14b8 adds the voltage amplitude decoupling correction value Va_ff output from the decoupling correction value calculator 14b7A to the PI voltage command value Va_pi output from the voltage amplitude regulator 14b1 according to equation (23), thereby obtaining the voltage amplitude command value Va_pi in which the induced voltage interference is decoupling. * Generate.

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[0061] <Configuration of normal control region voltage command value generator> 7 is a diagram illustrating a configuration example of a normal control region voltage command value generator according to the first embodiment of the present disclosure. In FIG. 7, the normal control region voltage command value generator 14a-1 includes a current command value calculator 14a1, subtractors 18 and 19, a voltage command value calculator 20, adders 21 and 22, and a decoupling correction value calculator 36.

[0062] The current command value calculator 14a1 calculates the torque command value T * The q-axis current command value Iq is calculated based on the intersection of the constant torque curve, which is the current locus where Iq is constant, and the MTPA control curve. * and d-axis current command value Id * Calculate.

[0063] Here, the intersection point between the constant torque curve and the MTPA control curve can be calculated using, for example, the motor torque equation shown in equation (7) and equation (18) which shows the relationship between the d-axis current Id and the q-axis current Iq on the MTPA control curve. Note that on the right-hand side of equation (7), the first term represents the magnet torque and the second term represents the reluctance torque, with the magnet torque including only the q-axis current Iq and the reluctance torque including both the q-axis current Iq and the d-axis current Id. Therefore, by appropriately controlling the q-axis current Iq and the d-axis current Id, it is possible to generate an appropriate torque in the motor M.

[0064] By eliminating the d-axis current Id from equations (8) and (18), equation (24), which is a quartic equation related to the q-axis current Iq, can be obtained.

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[0065] As a solution to the quartic equation shown in equation (24), for example, Newton's method or the like is used for the quartic equation shown in equation (24), and the torque command value T * The q-axis current command value Iq at the intersection of the constant torque curve and the MTPA control curve *Furthermore, the current command value calculator 14a1 can derive a solution corresponding to the q-axis current command value Iq * Based on this, the d-axis current command value Id * Calculate.

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[0066] The subtractor 18 subtracts the d-axis current command value Id output from the current command value calculator 14a1. * The d-axis current command value Id is obtained by subtracting the d-axis current Id output from the u, v, w / dq converter 29 from the * The subtractor 19 calculates the d-axis current error Id_diff, which is the error between the q-axis current command value Iq output from the current command value calculator 14a1. * The q-axis current command value Iq is obtained by subtracting the q-axis current Iq output from the u, v, w / dq converter 29 from the * and the q-axis current Iq, which is the error between the q-axis current Iq and the q-axis current Iq, is calculated.

[0067] The voltage command value calculator 20 calculates a pre-decoupling d-axis voltage command value Vdt by performing PI control on the d-axis current error Id_diff according to equation (26.1). The voltage command value calculator 20 also calculates a pre-decoupling q-axis voltage command value Vqt by performing PI control on the q-axis current error Iq_diff according to equation (26.2). Note that kp_d in equation (26.1) and kp_q in equation (26.2) are proportional gains, and ki_d in equation (26.1) and ki_q in equation (26.2) are integral gains.

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[0068] The decoupling correction value calculator 36 generates a d-axis decoupling correction value Vda for correcting the pre-decoupling d-axis voltage command value Vdt according to equation (27) based on the electrical angle estimated angular velocity ωe output from the PLL controller 31 and the d-axis current Id and q-axis current Iq output from the u,v,w / dq converter 29. The decoupling correction value calculator 36 also generates a q-axis decoupling correction value Vqa for correcting the pre-decoupling q-axis voltage command value Vqt according to equation (28) based on the electrical angle estimated angular velocity ωe output from the PLL controller 31 and the d-axis current Id and q-axis current Iq output from the u,v,w / dq converter 29. The d-axis decoupling correction value Vda and the q-axis decoupling correction value Vqa are correction values ​​for canceling interference terms between the d and q axes in a feedforward manner. To ensure stable control, the decoupling correction values ​​are preferably DC values. For this reason, when generating the decoupling correction value, the electric angular velocity command value ωe input from outside the motor control device 100a (for example, from a higher-level controller) is used. * Alternatively, the d-axis current Id and the q-axis current Iq may be obtained by removing noise components using an IIR filter (Infinite Impulse Response Filter). The IIR filter is an example of a noise removal filter.

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[0069] The adder 21 adds the d-axis decoupling correction value Vda to the pre-decoupling d-axis voltage command value Vdt in accordance with equation (29) to obtain the d-axis voltage command value Vd * The adder 22 calculates the q-axis voltage command value Vq by adding the q-axis decoupling correction value Vqa to the pre-decoupling q-axis voltage command value Vqt according to the equation (30). * As a result, the d-axis voltage command value Vd * and q-axis voltage command value Vq* is calculated.

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[0070] The first embodiment of the present disclosure has been described above.

[0071] [Example 2] <Configuration of voltage saturation region voltage command value generator> FIG. 8 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to a second embodiment of the present disclosure. A voltage saturation region voltage command value generator 14b-1b illustrated in FIG. 8 corresponds to the voltage saturation region voltage command value generator 14b-1 illustrated in FIG. 1. In FIG. 8, the voltage saturation region voltage command value generator 14b-1b includes a voltage amplitude adjuster 14b1, an induced voltage command value calculator 14b2, a current command value calculator 14b3, a temporary voltage command value calculator 14b4, a voltage phase adjuster 14b5A, a voltage command value calculator 14b6, a decoupling correction value calculator 14b7B, an adder 14b8, an LPF (Low Pass Filter) processor 14b9, and a Pn processor 14b10. Differences from the voltage saturation region voltage command value generator 14b-1a according to the first embodiment will be described below.

[0072] The LPF processor 14b9 removes high-frequency noise from the d-axis current Id and the q-axis current Iq by performing LPF processing on the d-axis current Id and the q-axis current Iq output from the u, v, w / dq converter 29, and outputs Id_LPF, which is the d-axis current after the high-frequency noise has been removed, and Iq_LPF, which is the q-axis current after the high-frequency noise has been removed, to the decoupling correction value calculator 14b7B.

[0073] The Pn processor 14b10 receives the mechanical angular velocity command value ωm input to the motor control device 100a from outside the motor control device 100a (for example, from a higher-level controller). * is multiplied by the number of pole pairs Pn of the motor M to obtain the electrical angular velocity command value ωe *Calculate the electrical angular velocity command value ωe * to the decoupling correction value calculator 14b7B.

[0074] The non-interference correction value calculator 14b7B calculates a voltage amplitude non-interference correction value Va_ff for non-interference of induced voltage interference according to equations (31), (32), and (33), and outputs the calculated voltage amplitude non-interference correction value Va_ff to the adder 14b8.

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[0075] The second embodiment of the present disclosure has been described above.

[0076] [Example 3] <Configuration of voltage saturation region voltage command value generator> Fig. 9 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to a third embodiment of the present disclosure. Voltage saturation region voltage command value generator 14b-1c illustrated in Fig. 9 corresponds to voltage saturation region voltage command value generator 14b-1 illustrated in Fig. 1. In Fig. 9, voltage saturation region voltage command value generator 14b-1c includes a voltage amplitude adjuster 14b1, an induced voltage command value calculator 14b2, a current command value calculator 14b3, a temporary voltage command value calculator 14b4, a voltage phase adjuster 14b5A, a voltage command value calculator 14b6, a decoupling correction value calculator 14b7B, an adder 14b8, an LPF (Low Pass Filter) processor 14b9, a Pn processor 14b10, and a voltage limit processor 14b11. The following describes the differences between the voltage saturation region voltage command value generator 14b-1a of the first embodiment and the voltage saturation region voltage command value generator 14b-1b of the second embodiment.

[0077] The adder 14b8 calculates a voltage amplitude command value Va' by adding the PI voltage command value Va_pi output from the voltage amplitude regulator 14b1 and the voltage amplitude non-interference correction value Va_ff output from the non-interference correction value calculator 14b7B, and outputs the calculated voltage amplitude command value Va' to the voltage limit processor 14b11.

[0078] The voltage limit processor 14b11 receives the output voltage limit value Vdq_limit. The voltage limit processor 14b11 limits the voltage amplitude command value Va' received from the adder 14b8 in accordance with equations (34.1) and (34.2). That is, the voltage limit processor 14b11 limits the voltage amplitude command value Va' when the voltage amplitude command value Va' reaches the output voltage limit value Vdq_limit. * is limited to the output voltage limit value Vdq_limit.

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[0079] Voltage limit processor 14b11 limits integrator output Va_i (not shown) of voltage amplitude regulator 14b1, which is subjected to PI control, to voltage limit value Va_i_limit expressed by equation (35.1) in accordance with equation (35.2).

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[0080] The third embodiment of the present disclosure has been described above.

[0081] [Example 4] 10 is a diagram illustrating an example configuration of a motor control device according to a fourth embodiment of the present disclosure. In Fig. 10, a motor control device 100b includes a subtractor 11, a voltage command value generator 14, a control switching determination unit 15, a dq / u,v,w converter 23, a PWM modulator 24, and an IPM 25. The IPM 25 is connected to a motor M.

[0082] Furthermore, motor control device 100b has shunt resistor 26, current sensors 27a and 27b, and 3φ current calculator 28. Note that motor control device 100b may have either shunt resistor 26 or current sensors 27a and 27b.

[0083] The motor control device 100b also includes a u, v, w / dq converter 29, an axis error calculator 30, a PLL controller 31, a position estimator 32, and a 1 / Pn processor 33.

[0084] The voltage command value generator 14 includes a normal control region voltage command value generator 14a-2, a voltage saturation region voltage command value generator 14b-2, a switch SW1, and a switch SW2. The switch SW1 includes contacts 14c-1, 14c-2, and 14c-3. The switch SW2 includes contacts 14c-4, 14c-5, and 14c-6.

[0085] The differences from the motor control device 100a of the first embodiment will be described below.

[0086] In a motor control device 100b shown in FIG. 10, a subtractor 11 outputs the calculated angular velocity error Δωm to a normal control region voltage command value generator 14a-2 and a voltage saturation region voltage command value generator 14b-2.

[0087] <Configuration of voltage saturation region voltage command value generator> Fig. 11 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to a fourth embodiment of the present disclosure. Voltage saturation region voltage command value generator 14b-2a illustrated in Fig. 11 corresponds to voltage saturation region voltage command value generator 14b-2 illustrated in Fig. 10. In Fig. 11, voltage saturation region voltage command value generator 14b-2a includes voltage amplitude adjuster 14b1, voltage phase adjuster 14b5B, voltage command value calculator 14b6, decoupling correction value calculator 14b7A, adder 14b8, voltage saturation speed controller 14b12, and subtractor 14b13.

[0088] The voltage saturation speed controller 14b12 controls the d-axis current command value Id so that the angular velocity error Δωm approaches zero, for example, according to equation (36) using PI control. * The generated d-axis current command value Id * is output to the subtractor 14b13. In the equation (36), kp is a negative proportional gain of the PI control, and ki is a negative integral gain of the PI control.

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[0089] The subtractor 14b13 subtracts the d-axis current command value Id output from the voltage saturation speed controller 14b12. * The d-axis current error ΔId is calculated by subtracting the d-axis current Id output from the u, v, w / dq converter 29 from the voltage phase regulator 14b5B, and the calculated d-axis current error ΔId is output to the voltage phase regulator 14b5B.

[0090] The voltage phase regulator 14b5B adjusts the voltage phase command value δ so that the d-axis current error ΔId approaches zero, for example, according to equation (37) using PI control. * is adjusted, and the adjusted voltage phase command value δ * to the voltage command value calculator 14b6. In equation (37), kp is a proportional gain of a negative value in the PI control, and ki is an integral gain of a negative value in the PI control.

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[0091] <Configuration of normal control region voltage command value generator> 12 is a diagram illustrating a configuration example of a normal control region voltage command value generator according to a fourth embodiment of the present disclosure. In FIG. 12, the normal control region voltage command value generator 14a-2 includes adders 21 and 22, subtractors 18 and 19, a voltage command value calculator 20, a decoupling correction value calculator 36, a normal control speed controller 37, and a d-axis current command value calculator 38.

[0092] The normal speed controller 37 calculates the q-axis current command value Iq such that the angular speed error Δωm approaches zero, for example, according to equation (38) using PI control. * The generated q-axis current command value Iq * is output to the d-axis current command value calculator 38 and the subtractor 19. In equation (38), kp is the proportional gain of the PI control, and ki is the integral gain of the PI control.

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[0093] The d-axis current command value calculator 38 calculates the q-axis current command value Iq * Based on this, the d-axis current command value Id * The calculated d-axis current command value Id * is output to the subtractor 19.

[0094] The fourth embodiment of the present disclosure has been described above.

[0095] [Example 5] <Configuration of voltage saturation region voltage command value generator> FIG. 13 is a diagram illustrating a configuration example of a voltage saturation region voltage command value generator according to a fifth embodiment of the present disclosure. A voltage saturation region voltage command value generator 14b-2b illustrated in FIG. 13 corresponds to the voltage saturation region voltage command value generator 14b-2 illustrated in FIG. 10. In FIG. 13, the voltage saturation region voltage command value generator 14b-2b includes a voltage amplitude adjuster 14b1, a voltage phase adjuster 14b5C, a voltage command value calculator 14b6, a decoupling correction value calculator 14b7C, adders 14b8 and 14b14, a voltage saturation speed controller 14b12, and a subtractor 14b13. Differences from the voltage saturation region voltage command value generator 14b-2a according to the fourth embodiment will be described below.

[0096] Voltage phase adjuster 14b5B adjusts voltage phase command value δ_pi so that d-axis current error ΔId approaches zero, for example, according to equation (39) using PI control, and outputs the adjusted voltage phase command value δ_pi to adder 14b14. In equation (39), kp is a negative proportional gain of PI control, and ki is a negative integral gain of PI control.

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[0097] The decoupling correction value calculator 14b7C calculates a d-axis decoupling correction value Vd_ff and a q-axis decoupling correction value Vq_ff for decoupling induced voltage interference according to equations (20) and (21). Then, the decoupling correction value calculator 14b7C calculates a composite induced voltage vector amplitude from the d-axis decoupling correction value Vd_ff and the q-axis decoupling correction value Vq_ff according to equation (22), and outputs the calculated composite induced voltage vector amplitude to the adder 14b8 as a voltage amplitude decoupling correction value Va_ff.

[0098] Furthermore, the decoupling correction value calculator 14b7C calculates a voltage phase decoupling correction value δ_ff for decoupling the induced voltage interference according to equation (40) based on the d-axis decoupling correction value Vd_ff and the q-axis decoupling correction value Vq_ff, and outputs the calculated voltage phase decoupling correction value δ_ff to the adder 14b14.

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[0099] The adder 14b14 adds the voltage phase decoupling correction value δ_ff output from the decoupling correction value calculator 14b7C to the voltage phase command value δ_pi output from the voltage phase adjuster 14b5B in accordance with equation (41), thereby obtaining the voltage phase command value δ_pi in which the induced voltage interference is decoupling. * is calculated, and the calculated voltage phase command value δ * to the voltage command value calculator 14b6.

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[0100] The decoupling correction value calculator 14b7C of the fifth embodiment calculates the electrical angular velocity command value ωe in the same manner as the decoupling correction value calculator 14b7B of the second embodiment. * The voltage amplitude decoupling correction value Va_ff may be calculated based on Id_LPF, which is the d-axis current after high-frequency noise has been removed, and Iq_LPF, which is the q-axis current after high-frequency noise has been removed. The voltage saturation region voltage command value generator 14b-2b of the fifth embodiment may include a voltage limit processor 14b11, similar to the voltage saturation region voltage command value generator 14b-1c of the third embodiment.

[0101] The fifth embodiment has been described above.

[0102] As described above, the motor control device (motor control devices 100a and 100b of the embodiment) of the present disclosure includes a voltage command value generator (voltage command value generator 14 of the embodiment), a control switching determination unit (control switching determination unit 15 of the embodiment), and a decoupling correction value calculator (decoupling correction value calculators 14b7A, 14b7B, and 14b7C of the embodiment). The voltage command value generator generates a voltage command value for the motor based on a speed error between a speed command value and the speed of the motor (motor M of the embodiment). The control switching determination unit determines whether the control region of the motor is in a voltage saturation region. The decoupling correction value calculator calculates a correction value that decouplings interference due to the induced voltage of the motor. Then, when the control switching determination unit determines that the control region is in the voltage saturation region, the voltage command value generator generates a voltage amplitude of the output voltage applied to the motor and a voltage phase of the output voltage applied to the motor, and calculates a voltage command value corrected using the correction value.

[0103] For example, a motor control device (motor control devices 100a and 100b of the embodiments) of the present disclosure includes a current detector (shunt resistor 26 and 3φ current calculator 28 of the embodiments) that detects the motor current, and a converter (u, v, w / dq converter 29 of the embodiments) that converts the motor current detected by the current detector into a d-axis current and a q-axis current. When the control switching determination unit determines that the control region is in the voltage saturation region, the voltage command value generator adjusts the voltage amplitude of the motor output voltage based on the d-axis current and the q-axis current so that the motor current moves along the MTPA control curve, and calculates a voltage command value by adding a correction value to the adjusted voltage amplitude.

[0104] This makes it possible to eliminate interference caused by the induced voltage of the motor in the voltage saturation region, thereby suppressing instability in motor control without reducing the control response of the output voltage amplitude.

[0105] The motor control device (motor control device 100a of the embodiment) of the present disclosure also includes a subtractor (subtractor 11 of the embodiment) that calculates a speed error between a speed command value and the current speed of the motor, and a torque command value generator (speed controller 12 of the embodiment) that generates a torque command value according to the speed error. The voltage command value generator generates a voltage command value based on the torque command value.

[0106] By doing so, in a motor control device having a voltage command value generator that generates a voltage command value from a torque command value, the torque command value generator can be made common between the normal control region and the voltage saturation region.

[0107] Furthermore, the motor control device (motor control devices 100a and 100b of the embodiment) of the present disclosure includes a noise remover (LPF processor 14b9 of the embodiment) that removes noise contained in the motor current flowing through the motor. The non-interference correction value calculator calculates a correction value based on the motor current after the noise has been removed.

[0108] This prevents the motor control from becoming unstable due to noise being superimposed on the correction value.

[0109] Furthermore, the motor control device (motor control devices 100a and 100b of the embodiment) of the present disclosure includes an adder (adder 14b8 of the embodiment) that adds a correction value to the voltage amplitude and outputs the voltage amplitude to which the correction value has been added as the addition result, and a limiter (voltage limit processor 14b11 of the embodiment) that limits the addition result by the voltage amplitude of the maximum voltage. The voltage command value generator calculates a voltage command value based on the addition result.

[0110] This allows for a smooth transition from MTPA control to flux-weakening control by adjusting the voltage phase, and also prevents control instability caused by winding up of the integrator used to adjust the output voltage amplitude during flux-weakening control.

[0111] Furthermore, the motor control device (motor control device 100b of the embodiment) of the present disclosure includes a first subtractor (subtractor 11 of the embodiment), a d-axis current command value calculator (voltage saturation speed controller 14b12 of the embodiment), a second subtractor (subtractor 14b13 of the embodiment), and a voltage phase generator (voltage phase adjuster 14b5B of the embodiment). The first subtractor calculates a speed error between a speed command value and a current speed of the motor. The d-axis current command value calculator calculates a d-axis current command value according to the speed error. The second subtractor calculates a d-axis current error between the d-axis current command value and a current d-axis current of the motor. The voltage phase generator generates a voltage phase according to the d-axis current error. Then, the voltage command value generator calculates a voltage command value based on the voltage phase.

[0112] By doing this, even when the voltage phase is generated according to the d-axis current error, interference caused by the motor's induced voltage can be decoupled in the voltage saturation region, thereby suppressing instability in motor control without reducing the control response of the output voltage amplitude.

[0113] Furthermore, the non-interference correction value calculator (non-interference correction value calculator 14b7C in the embodiment) calculates a first correction value for correcting the voltage amplitude and a second correction value for correcting the voltage phase.

[0114] This makes it possible to correct both the voltage amplitude width and voltage phase, both of which are PI controlled, thereby further preventing a decrease in the control response of the output voltage amplitude and suppressing instability in motor control. [Explanation of symbols]

[0115] 100a, 100b Motor control device 14 Voltage command generator 15 Control switching determination unit 14b7A, 14b7B, 14b7C Decoupling correction value calculator 11,14b13 Subtractor 12 Speed ​​Controller 14b9 LPF processor 26 Shunt resistor 28 3φ current calculator 29 u,v,w / dq converter 14b8 adder 14b11 voltage limit processor 14b12 Voltage Saturation Speed ​​Controller 14b15 voltage phase regulator

Claims

1. a voltage command value generator that generates a voltage command value for the motor based on a speed error between a speed command value and the speed of the motor; a control switching determination unit that determines whether a control region of the motor is in a voltage saturation region; a non-interference correction value calculator for calculating a correction value for non-interference of interference caused by an induced voltage of the motor; Equipped with when the control switching determination unit determines that the control region is in the voltage saturation region, the voltage command value generator generates a voltage amplitude of an output voltage applied to the motor and a voltage phase of the output voltage applied to the motor, and calculates a voltage command value corrected by the correction value; a noise reducer for removing noise contained in a motor current flowing through the motor; the non-interference correction value calculator calculates the correction value based on the motor current after the noise has been removed; a current detector for detecting the motor current; a converter that converts the motor current detected by the current detector into a d-axis current and a q-axis current; Further comprising: when the control switching determination unit determines that the control region is in the voltage saturation region, the voltage command value generator adjusts a voltage amplitude of an output voltage of the motor based on the d-axis current and the q-axis current so that the motor current moves on an MTPA control curve, and calculates the voltage command value by adding the correction value to the adjusted voltage amplitude; an adder that adds the correction value to the voltage amplitude and outputs the voltage amplitude to which the correction value has been added as an addition result; a limiter that limits the summation result by a limit value of the voltage amplitude; Further comprising: the voltage command value generator calculates the voltage command value based on the addition result; the limiter limits the sum by the limit value, which is a value obtained by subtracting the correction value from a predetermined value. Motor control device.

2. a voltage command value generator that generates a voltage command value for the motor based on a speed error between a speed command value and the speed of the motor; a control switching determination unit that determines whether a control region of the motor is in a voltage saturation region; a non-interference correction value calculator for calculating a correction value for non-interference of interference caused by an induced voltage of the motor; Equipped with when the control switching determination unit determines that the control region is in the voltage saturation region, the voltage command value generator generates a voltage amplitude of an output voltage applied to the motor and a voltage phase of the output voltage applied to the motor, and calculates a voltage command value corrected by the correction value; a noise reducer for removing noise contained in a motor current flowing through the motor; the non-interference correction value calculator calculates the correction value based on the motor current after the noise has been removed; a current detector for detecting the motor current; a converter that converts the motor current detected by the current detector into a d-axis current and a q-axis current; Further comprising: when the control switching determination unit determines that the control region is in the voltage saturation region, the voltage command value generator adjusts a voltage amplitude of an output voltage of the motor based on the d-axis current and the q-axis current so that the motor current moves on an MTPA control curve, and calculates the voltage command value by adding the correction value to the adjusted voltage amplitude; a first subtractor that calculates a speed error between the speed command value and the speed of the motor; a d-axis current command value calculator that calculates a d-axis current command value in accordance with the speed error; a second subtractor that calculates a d-axis current error between the d-axis current command value and the d-axis current of the motor; a voltage phase generator that generates the voltage phase in response to the d-axis current error; Further comprising: the voltage command value generator calculates the voltage command value based on the voltage phase. Motor control device.

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