JP5397664B2 - Motor control device - Google Patents

Description

  The present invention relates to a motor control device for driving a motor (particularly a brushless motor). The brushless motor is used, for example, as a source for generating a steering assist force in an electric power steering apparatus.

  A motor control device for a brushless motor includes a current detection unit that detects a current flowing through an armature winding of the motor, a rotation angle detection unit that detects a rotor rotation angle of the motor, a d-axis target current, and a q-axis target current. A dq-axis target current calculator, a dq-axis current calculator that calculates a d-axis current and a q-axis current based on the detected armature winding current and rotor rotation angle, a d-axis voltage command value calculator, And a q-axis voltage command value calculation unit. The d-axis voltage command value calculation unit obtains a d-axis voltage command value based on the PI calculation of the d-axis deviation so as to reduce the d-axis deviation between the d-axis target current and the d-axis current. The q-axis voltage command value calculation unit obtains the q-axis voltage command value based on the PI calculation of the q-axis deviation so as to reduce the q-axis deviation between the q-axis target current and the q-axis current. Based on the d-axis voltage command value, the q-axis voltage command value, and the detected rotor rotation angle, the motor control device applies a voltage to the armature winding. Thereby, the rotational force of the rotor is generated.

On the other hand, non-interference control is known in which a non-interference control amount is added to a PI calculation value (see Patent Document 1). Non-interacting control is to cancel the interference between the d-axis control system and the q-axis control system by determining the voltage command value so as to compensate the speed electromotive force generated inside the motor as the rotor rotates. Control. By performing the non-interacting control, it is expected that a decrease in response and tracking performance due to speed electromotive force can be effectively suppressed.
JP 2005-82034 A

The speed electromotive force generated inside the motor depends on the rotational angular speed and the current. Therefore, the non-interacting control amount for compensating for this also depends on the rotational angular velocity and the current. More specifically, the d-axis decoupling control amount depends on the rotation angular velocity and the q-axis current, and the q-axis decoupling control amount depends on the rotation angular velocity and the d-axis current.
However, it takes time to calculate the rotational angular velocity and the like from the detection of the current until the calculation of the non-interacting control amount is completed. Therefore, the change in the non-interacting control amount is delayed from the change in the speed electromotive force inside the motor. Even if the voltage command value is corrected using such a non-interacting control amount, the motor current cannot always be controlled to an ideal waveform. Therefore, the non-interacting control may not always produce the expected effect.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a motor control device that can satisfactorily control a motor current by compensating for a shift in a non-interacting control amount caused by a calculation time from current detection.

  In order to achieve the above object, the invention according to claim 1 is the following: motor current detection means (11) for detecting the motor current flowing in the motor (1), target current value and motor detected by the motor current detection means. A basic voltage command value generating means (51a, 52a) for generating a basic voltage command value based on a deviation from the current, a rotational angular velocity calculating means (22) for calculating the rotational angular speed of the motor, and the motor current detecting means Non-interacting control amount computing means (51b, 52b) for computing a non-interacting control amount for non-interacting control of the motor based on the detected motor current and the rotational angular speed computed by the rotational angular speed computing means. And a motor voltage estimating means (5) for estimating a motor voltage by performing a phase advance calculation on the motor current detected by the motor current detecting means. c, 52c), correction value calculation means (51d, 52d) for calculating a correction value based on the estimated motor voltage estimated by the motor voltage estimation means and the basic voltage command value generated by the basic voltage command value generation means ), A correction means (51e, 52e) for correcting the basic voltage command value generated by the basic voltage command value generation means with the non-interacting control amount and the correction value, and a correction command (51e, 52e). And a drive means (20, 21, 13) for driving the motor using the voltage command value. In addition, the alphanumeric characters in parentheses represent corresponding components in the embodiments described later. The same applies hereinafter.

  According to this configuration, the basic voltage command value is generated based on the deviation between the target current value and the motor current, while the phase advance calculation is performed on the motor current detected by the motor current detecting means to The voltage is estimated. Specifically, the estimated motor voltage is obtained by correcting the basic voltage command value with a non-interacting control amount or the like to obtain a voltage command value, and the motor voltage at the time of driving the motor using this voltage command value. An estimated value is preferred. A correction value is obtained based on the difference between the estimated motor voltage and the basic voltage command value. This correction value is the amount of deviation of the non-interacting control amount that occurs during the calculation time from when the motor current is detected until the rotational angular velocity is calculated and further the non-interacting control amount is calculated and the voltage command value is obtained. This corresponds to an error from an appropriate non-interacting control amount). Therefore, the basic voltage command value is corrected not only by the non-interacting control amount but also by the correction value. This makes it possible to perform non-interference control that compensates for a delay in calculation time, so that the motor current waveform can be brought close to an ideal waveform, and the response and follow-up performance of the motor can be effectively improved. .

The invention according to claim 2 is the motor control device according to claim 1, wherein the phase advance calculation performed by the motor voltage estimating means is defined by a time constant of the motor.
According to this configuration, since the phase advance calculation is defined by the time constant of the motor, it is possible to obtain an estimated motor voltage having a value approximate to the motor voltage when the motor is driven by the voltage command value. Thereby, since the shift | offset | difference of a non-interacting control amount can be compensated more appropriately, the effect by non-interacting control can be increased further.

According to a third aspect of the present invention, the correction value calculating means obtains the correction value by multiplying a deviation between the estimated motor voltage and the basic voltage command value by a gain of 1 or less. Or it is the motor control apparatus of 2 description.
According to this configuration, since the correction value is obtained by multiplying the deviation between the estimated motor voltage and the basic voltage command value by a gain of 1 or less, the non-interacting control amount can be corrected appropriately. The effect of correction is maximized when the gain is 1, but the degree of correction can be adjusted by setting the gain value to an appropriate value of 1 or less (however, a value greater than 0).

  The motor current detection means comprises: a phase current detection means (11) for detecting a phase current flowing in the armature winding of the motor; and a phase coordinate detected by the phase current detection means based on the rotor rotation angle ( For example, it may include coordinate conversion means (17) for converting into a current value of dq coordinate system). In this case, the coordinate conversion means (17) may perform coordinate conversion processing based on the output of the rotation angle detection means (2) that detects the rotor rotation angle.

  The basic voltage command value generating means calculates a d-axis basic voltage command value and a q-axis basic voltage command value, and the non-interacting control amount calculating means is a d-axis non-interacting control amount and a q-axis non-interacting control amount. An interference control amount is calculated; the motor voltage estimating means calculates a d-axis estimated voltage and a q-axis estimated voltage; and the correction value calculating means is a d-axis estimated voltage and a d-axis basic voltage. A d-axis correction value is obtained based on the command value, and a q-axis correction value is obtained based on the q-axis estimated voltage and the q-axis basic voltage command value. The correction means converts the d-axis basic voltage command value into the d-axis. A d-axis voltage command value is obtained by correction based on the non-interacting control amount and the d-axis correction value, and a q-axis basic voltage command value is corrected based on the q-axis non-interacting control amount and the q-axis correction value to obtain q A shaft voltage command value is obtained, and the driving means includes a d-axis power It may be one that drives the motor based on the command value and q-axis voltage command value.

In this case, the non-interacting control amount calculating means calculates the d-axis non-interacting control amount D _d according to the following equation A, and calculates the q-axis non-interacting control amount D _q according to the following equation B. May be.
D _d = −ωL _q I _q ... A
D _q = ωL _d I _d + ωΦ ... B
Where ω is the rotational speed of the motor (rad / sec), L _d is the d-axis inductance (H), L _q is the q-axis inductance (H), I _d is the d-axis current (A), and I _q is the q-axis current. (A) and Φ respectively represent √ (3/2) times the maximum value of the number of U, V, W phase armature winding interlinkage magnetic fluxes of the motor field.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a block diagram for explaining an electrical configuration of an electric power steering apparatus to which a motor control apparatus according to an embodiment of the present invention is applied. This electric power steering apparatus includes a torque sensor 7 that detects a steering torque applied to a steering wheel of a vehicle, a vehicle speed sensor 8 that detects the speed of the vehicle, a motor 1 that applies a steering assist force to the steering mechanism 3 of the vehicle, And a motor control device 10 for driving and controlling the motor 1. The motor control device 10 drives the motor 1 in accordance with the steering torque detected by the torque sensor 7 and the vehicle speed detected by the vehicle speed sensor 8, thereby realizing appropriate steering assistance according to the steering situation. The motor 1 is, for example, a three-phase brushless motor.

The motor control device 10 includes a current detection unit 11, a microcomputer 12 as a signal processing unit, and a drive circuit 13. A torque sensor 7 and a vehicle speed sensor 8 described above are connected to the motor control device 10 together with a resolver 2 (rotation angle sensor) that detects the rotation angle of the rotor in the motor 1.
The current detection unit 11 detects a current flowing through the armature winding of the motor 1. More specifically, the current detector 11 includes current detectors 11u, 11v, and 11w that detect phase currents in three-phase (U-phase, V-phase, and W-phase) armature windings, and a current detector 11u. , 11v, 11w have A / D converters 11u ′, 11v ′, 11w ′ for A / D (analog / digital) conversion of current detection signals.

  The microcomputer 12 includes a plurality of function processing units realized by program processing (software processing). The plurality of function processing units include a basic target current calculation unit 15, a dq axis target current calculation unit 16, a dq axis current calculation unit 17, a d axis deviation calculation unit 18d, a q axis deviation calculation unit 18q, and a dq axis voltage command. A value calculation unit 19, a voltage command value coordinate conversion unit 20, a PWM (pulse width modulation) control unit 21, and a rotation angular velocity calculation unit 22 are included.

The drive circuit 13 is composed of an inverter circuit and is controlled by the PWM control unit 21 to supply power from a power source such as an in-vehicle battery to the U-phase, V-phase, and W-phase armature windings of the motor 1. A phase current flowing between the drive circuit 13 and the armature winding of each phase of the motor 1 is detected by current detectors 11u, 11v, and 11w.
The basic target current calculation unit 15 calculates the basic target current I ^* of the motor 1 based on the steering torque detected by the torque sensor 7 and the vehicle speed detected by the vehicle speed sensor 8. For example, the basic target current I ^* is determined so as to increase as the steering torque increases and increase as the vehicle speed decreases.

The basic target current I ^* calculated by the basic target current calculation unit 15 is input to the dq-axis target current calculation unit 16. The dq axis target current calculation unit 16 calculates a d axis target current I _d ^* for generating a magnetic field in the d axis direction and a q axis target current I _q ^* for generating a magnetic field in the q axis direction. The d-axis is an axis along the magnetic flux direction of the field of the rotor of the motor 1, and the q-axis is an axis orthogonal to the d-axis and the rotor rotation axis. The calculation in the dq-axis target current calculation unit 16 can be performed using a known calculation formula.

The phase currents Iu, Iv, Iw output from the current detection unit 11 are input to the dq axis current calculation unit 17. The dq-axis current calculation unit 17 calculates the d-axis current I _d and the q-axis current I _q by performing coordinate conversion on the phase currents Iu, Iv, and Iw based on the rotor rotation angle detected by the resolver 2. The calculation in the dq axis current calculation unit 17 can be performed using a known calculation formula.

The d-axis deviation calculating unit 18d obtains a d-axis deviation δI _d between the d-axis target current I _d ^* and the d-axis current I _d . Similarly, the q-axis deviation calculating unit 18q obtains a q-axis deviation δI _q between the q-axis target current I _q ^* and the q-axis current I _q .
The dq-axis voltage command value calculation unit 19 obtains a d-axis voltage command value V _d ^* corresponding to the d-axis deviation δI _d and a q-axis voltage command value V _q ^* corresponding to the q-axis deviation δI _q .

The voltage command value coordinate conversion unit 20 performs coordinate conversion of the d-axis voltage command value V _d ^* and the q-axis voltage command value V _q ^* based on the rotor rotation angle detected by the resolver 2, and performs U-phase armature winding. Applied voltage command values Vu ^* , Vv ^* , Vw ^* to be applied to the wire, the V-phase armature winding, and the W-phase armature winding are calculated. The calculation in the voltage command value coordinate conversion unit 20 may be performed using a known calculation formula.

The PWM control unit 21 generates a PWM control signal for each phase, which is a pulse signal having a duty ratio corresponding to the applied voltage command values Vu ^* , Vv ^* , and Vw ^* . As a result, voltages corresponding to the d-axis voltage command value V _d ^* and the q-axis voltage command value V _q ^* are applied from the drive circuit 13 to the armature windings of the respective phases, and the rotational force of the rotor is generated.
The rotation angular velocity calculation unit 22 calculates a rotation angular velocity ω (rad / sec) by calculating a temporal change (differentiation) of the rotor rotation angle detected by the resolver 2. The rotational angular velocity ω is input to the dq axis voltage command value calculation unit 19.

FIG. 2 is a block diagram for explaining a detailed configuration of the dq-axis voltage command value calculation unit 19.
The dq-axis voltage command value calculation unit 19 includes a d-axis voltage command value calculation unit 51 and a q-axis voltage command value calculation unit 52. d-axis voltage command value computing part 51, so as to reduce the d-axis deviation .delta.I _d, d-axis deviation .delta.I _d of the PI calculation (hereinafter referred to as "d-axis PI calculation".) d-axis voltage command value based on such V _{Find d} ^* . q-axis voltage command value calculating unit 52, so as to reduce the q-axis deviation .delta.I _q, q-axis deviation .delta.I _q of the PI calculation (hereinafter "q-axis PI calculation" hereinafter.) q-axis voltage command value based on such V _{Find q} ^* .

The d-axis voltage command value calculation unit 51 includes a d-axis PI calculation unit 51a, a d-axis decoupling control amount calculation unit 51b, a d-axis voltage estimation unit 51c, a d-axis correction value calculation unit 51d, and a d-axis correction. Part 51e.
d-axis PI calculation portion 51a is for feedback control of the d-axis current, calculates a d-axis PI calculation value V _d0 as d-axis fundamental voltage command value by the PI calculation of the d-axis deviation .delta.I _d, the d-axis the PI calculation value V _d0 and outputs the d-axis correction unit 51e. The d-axis voltage command value V _d ^* is obtained by correcting the d-axis PI calculation value V _d0 by the d-axis correction unit 51e.

The d-axis non-interacting control amount calculation unit 51b is based on the q-axis current I _q obtained by the dq-axis current calculation unit 17 and the rotation angular velocity ω (rad / sec) obtained by the rotation angular velocity calculation unit 22. The non-interacting control amount _Dd is obtained. More specifically, the d-axis non-interacting control amount calculation unit 51b calculates the d-axis non-interacting control amount D _{d according} to the following equation (1).
D _d = −ωL _q I _q (1)
In the equation, L _q is the q-axis self-inductance of the armature winding of the motor 1, and is a constant that has been measured in advance.

The d-axis voltage estimator 51c multiplies the d-axis current I _d by the armature winding resistance (motor resistance) R and the phase advance with respect to the d-axis current I _d (value obtained by multiplying the motor resistance R). A phase advance calculation unit 61b that performs calculation, and a low-pass filter 61c that performs a smoothing process on the d-axis current I _d (value multiplied by the motor resistance R) after the phase advance calculation is included. With this configuration, the d-axis voltage estimation unit 51c estimates the motor voltage (d-axis voltage) when driving the motor 1 based on the d-axis voltage command value V _d ^* , and generates the d-axis estimated voltage V ^E _d . . That is, since the motor current is detected, the rotation angular velocity ω is calculated, d-axis PI calculation value V _d0 is calculated, the correction by the d-axis correction unit 51e is performed on the addition d-axis PI calculation value V _d0 In consideration of the delay time until the d-axis voltage command value V _d ^* , the d-axis estimated voltage V ^E _d when the motor drive is actually performed is obtained.

The transfer function of the phase advance calculation unit 61b is expressed as (T _md s + 1) / (T _L1 s + 1), and the transfer function of the low-pass filter 61c is expressed as 1 / (T _L2 s + 1). s is a Laplace operator. T _md is a time constant of the motor, and is expressed as T _md = L _d / R by the d-axis inductance L _d and the motor resistance R. T _L1 and T _L2 are time constants of the low-pass filter. The numerator (T _md s + 1) of the transfer function of the phase advance calculation unit 61b is a phase advance element. The primary delay element 1 / (T _L1 s + 1) of the phase advance calculation unit 61b suppresses the gain of the phase advance calculation unit 61b from becoming infinite. The low-pass filter 61c is for removing and smoothing noise generated by the phase advance calculation by the phase advance calculation unit 61b.

The d-axis correction value calculation unit 51d is a deviation calculation unit 63a that calculates a deviation ΔV _d (= V ^E _d −V _d0 ) between the d-axis estimated voltage V ^E _d and the d-axis PI calculation value V _d0, and this deviation ΔV _d. Is multiplied by a gain K (where 0 <K ≦ 1) to obtain a d-axis correction value C _d (= K · ΔV _d ). The d-axis correction value C _d generated by the multiplier 63b is provided to the d-axis correction unit 51e. The d-axis correction value C _d corresponds to a deviation amount (error) of the d-axis non-interacting control amount D _d in the delay time from when the motor current is detected until the driving with the d-axis voltage command value V _d ^* is performed. To do.

d-axis correction unit 51e includes a non-interacting control correction unit 65a for adding the d-axis non-interacting control amount D _d to the d-axis PI calculation value V _d0, d-axis correction from the output of the non-interacting control correction unit 65a and a delay correction section 65b which subtract the value C _d. With this configuration, the d-axis PI calculation value V _d0 is corrected with the d-axis non-interacting control amount D _d and the d-axis correction value C _d to obtain the d-axis voltage command value V _d ^* . Of course, previously subjected to subtraction of the d-axis correction value C _d with respect to the d-axis PI calculation value V _d0, it may be added to the d-axis non-interacting control amount D _d with respect to the results of that. Further, it performs subtraction of the d-axis correction value C _d with respect to the d-axis non-interacting control amount D _d (i.e., corrects the d-axis non-interacting control amount D _d), this result (corrected d The axis non-interacting control amount D _d ) may be added to the d-axis PI calculation value V _d0 . In either case, the d-axis voltage command value V _d ^* is given by the following equation (2).

^{_{V d * = V d0 + D}} d - C d ... (2)
The d-axis voltage command value V _d ^* is a value obtained by correcting a deviation amount (error) caused by a calculation delay of the non-interacting control amount D _d .
The q-axis voltage command value calculation unit 52 includes a q-axis PI calculation unit 52a, a q-axis decoupling control amount calculation unit 52b, a q-axis voltage estimation unit 52c, a q-axis correction value calculation unit 52d, and a q-axis correction. Part 52e.

The q-axis PI calculation unit 52a performs feedback control of the q-axis current, calculates the q-axis PI calculation value V _q0 as the q-axis basic voltage command value by the PI calculation of the q-axis deviation δI _q , and this q-axis The PI calculation value V _q0 is output to the q-axis correction unit 52e. The q-axis voltage command value V _q ^* is obtained by correcting the q-axis PI calculation value V _q0 by the q-axis correction unit 52e.
The q-axis non-interacting control amount calculation unit 52b is based on the d-axis current I _d obtained by the dq-axis current calculation unit 17 and the rotation angular velocity ω (rad / sec) obtained by the rotation angular velocity calculation unit 22. A non-interacting control amount D _q is obtained. More specifically, the q-axis non-interacting control amount calculation unit 52b calculates the q-axis non-interacting control amount D _{q according} to the following equation ( 3 ).

D _q = ωL _d I _d + ωΦ ( 3 )
In the equation, L _d is the d-axis self-inductance of the armature winding of the motor 1 and is a constant measured in advance. Also, Φ is (3/2) ^1/2 times the maximum value of the number of U, V, W phase armature winding linkage magnetic fluxes of the rotor field.
The q-axis voltage estimator 52c advances the phase with respect to the multiplier 62a that multiplies the q-axis current _Iq by the armature winding resistance (motor resistance) R and the q-axis current _Iq (a value that is multiplied by the motor resistance R). A phase advance calculation unit 62b that performs calculation, and a low-pass filter 62c that performs a smoothing process on the q-axis current I _q (value multiplied by the motor resistance R) after the phase advance calculation is included. With this configuration, the q-axis voltage estimation unit 52c estimates the motor voltage (q-axis voltage) when driving the motor 1 based on the q-axis voltage command value V _q ^* , and generates the q-axis estimated voltage V ^E _q . . That is, the motor current is detected, the rotation angular velocity ω is calculated, the q-axis PI calculation value V _q0 is calculated, the correction by the q-axis correction unit 52e is performed on the further q-axis PI calculation value V _q0 Q-axis estimated voltage V ^E _q when the motor is actually driven by the q-axis voltage command value V _q ^* is obtained in consideration of the delay time until.

The transfer function of the phase advance calculation unit 62b is expressed as (T _mq s + 1) / (T _L1 s + 1), and the transfer function of the low-pass filter 62c is expressed as 1 / (T _L2 s + 1). s is a Laplace operator. T _mq is a time constant of the motor and is expressed as T _mq = L _q / R by the q-axis inductance L _q and the motor resistance R. T _L1 and T _L2 are time constants of the low-pass filter. The numerator (T _mq s + 1) of the transfer function of the phase advance calculation unit 62b is a phase advance element. The first-order lag element 1 / (T _L1 s + 1) of the phase advance calculation unit 62b suppresses the gain of the phase advance calculation unit 62b from becoming infinite. The low-pass filter 62c is for removing and smoothing noise generated by the phase advance calculation by the phase advance calculation unit 62b.

The q-axis correction value calculation unit 52d includes a deviation calculation unit 64a for _obtaining a deviation ΔV _q (= V ^E _q −V _q0 ) between the q-axis estimated voltage V ^E _q and the q-axis PI calculation value V _q0, and this deviation ΔV _q Is multiplied by a gain K (where 0 <K ≦ 1) to obtain a q-axis correction value C _q (= K · ΔV _q ). The q-axis correction value C _q generated by the multiplier 64b is supplied to the q-axis correction unit 52e. The q-axis correction value C _q corresponds to a deviation amount (error) of the q-axis non-interacting control amount D _q in the delay time from when the motor current is detected until the driving with the q-axis voltage command value V _q ^* is performed. To do.

The q-axis correction unit 52e adds a q-axis non- _interacting control amount D _q to the q-axis PI calculation value V _q0 , and performs q-axis correction from the output of the non-interacting control correction unit 66a. and a delay correction section 66b which subtract the value C _q. With this configuration, the q-axis PI calculation value V _q0 is corrected with the q-axis non- _interacting control amount D _q and the q-axis correction value C _q to obtain the q-axis voltage command value V _q ^* . Of course, previously subjected to subtraction of the q-axis correction value C _q with respect to the q-axis PI calculation value V _q0, it may be added to the q-axis non-interacting control amount D _q with respect to a result of it. Further, it performs subtraction of the q-axis correction value C _q with respect to the q-axis non-interacting control amount D _q (i.e., corrects the q-axis non-interacting control amount D _q), this result (corrected q The axis decoupling control amount D _q ) may be added to the q-axis PI calculation value V _q0 . In either case, the q-axis voltage command value V _q ^* is given by the following equation ( 4 ).

^{_{V q * = V q0 + D}} q - C q ... (4)
The q-axis voltage command value V _q ^* is a value obtained by correcting a deviation amount (error) caused by a calculation delay of the non-interacting control amount D _q .
FIG. 3 is a flowchart for explaining a control procedure of the motor 1 by the motor control device 10. First, the microcomputer 12 reads detection values obtained by the torque sensor 7, the vehicle speed sensor 8, the current detectors 11u, 11v, 11w, and the resolver 2 (step S1). The basic target current calculation unit 15 calculates the target current I ^* based on the detected steering torque and vehicle speed (step S2). dq axis target current calculation unit 16 calculates and its target current d-axis target current corresponding to I ^* I _d ^* and q axis target current I _q ^* (step S3). The dq axis current calculation unit 17 calculates the d axis current I _d and the q axis current I _q corresponding to the detected phase currents Iu, Iv, Iw (step S4). From the d-axis target current I _d ^* and the d-axis current I _d , the d-axis deviation calculation unit 18d calculates the d-axis deviation δI _d , and from the q-axis target current I _q ^* and the q-axis current I _q , q In the axis deviation calculator 18q, the q axis deviation δI _q is calculated (step S5). Further, the rotation angular velocity calculation unit 22 calculates the rotation angular velocity ω based on the rotor rotation angle detected by the resolver 2 (step S6).

Next, the dq-axis voltage command value calculation unit 19 calculates the d-axis voltage command value V _d ^* and the q-axis voltage command value V _q ^* (step S7). Then, in the voltage command value coordinate conversion unit 20, a U-phase armature winding, a V-phase armature winding, and a W-phase armature winding corresponding to the d-axis voltage command value V _d ^* and the q-axis voltage command value V _q ^* . Applied voltage command values Vu ^* , Vv ^* , Vw ^{* to the line} are calculated (step S8). PWM control signals corresponding to these applied voltage command values Vu ^* , Vv ^* , Vw ^* are given from the PWM control unit 21 to the drive circuit 13. Thereby, the motor 1 is driven (step S9). Then, whether or not to end the control is determined by, for example, turning on or off the ignition switch (step S10). If not, the process returns to step S1.

FIG. 4 is a flowchart showing a calculation procedure of the d-axis voltage command value V _d ^* and the q-axis voltage command value V _q ^* . First, the d-axis PI calculation value V _d0 and the q-axis PI calculation value V _q0 are obtained by the d-axis PI calculation and the q-axis PI calculation (step S101). Using the rotation angular velocity ω calculated by the rotation angular velocity calculation unit 22, the d-axis non-interacting control amount calculation unit 51b obtains the d-axis non-interacting control amount D _d , and the q-axis non-interacting control amount calculation unit 52b. In step S102, the q-axis decoupling control amount _Dq is obtained. The d-axis estimated voltage V ^E _d is obtained by the d-axis voltage estimator 51c, and the q-axis estimated voltage V ^E _q is obtained by the q-axis voltage estimator 52c (step S103).

Further, the d-axis correction value calculation unit 51d is required d-axis correction value C _d, q-axis correction value C _q in the q-axis correction value calculation unit 52d is determined (step S104).
Then, in the d-axis correction unit 51e, the d-axis voltage command value V _d ^* is obtained by correcting the d-axis PI calculation value V _d0 by the d-axis _decoupling control amount D _d and the d-axis correction value C _d ( Step S105). Further, the q-axis correction unit 52e, the q-axis PI calculation value V _q0 to q-axis non-interacting control amount D _q and is correction by the q-axis correction value C _q q-axis voltage command value V _q ^* are calculated ( Step S105). The d-axis voltage command value V _d ^* and the q-axis voltage command value V _q ^* thus obtained are output.

As described above, according to this embodiment, the correction values C _d , generated based on the estimated voltages V ^E _d , V ^E _q are the effects of the delay time due to the calculation of the non-interacting control amounts D _d , D _q . Compensation is performed by C _q . Thereby, since non-interference control can be performed satisfactorily, the current waveform can be approximated to an ideal waveform, and the response and followability of the motor 1 can be improved. The steering feeling in the electric power steering device can be improved.

Although one embodiment of the present invention has been described above, the present invention can be implemented in other forms. For example, in the above-described embodiment, the rotor rotation angle is detected by the resolver 2, but the rotor rotation angle may be estimated by so-called sensorless control. Then, the rotational angular velocity ω may be calculated based on the estimated rotor rotational angle.
In the above-described embodiment, the example in which the present invention is applied to the motor as the drive source of the electric power steering apparatus has been described. However, the present invention is also applicable to the control of a motor for applications other than the electric power steering apparatus. Applicable.

  In addition, various design changes can be made within the scope of matters described in the claims.

1 is a block diagram for explaining an electrical configuration of an electric power steering device to which a motor control device according to an embodiment of the present invention is applied. FIG. It is a block diagram for demonstrating the detailed structure of a dq axis voltage command value calculating part. It is a flowchart for demonstrating the control procedure of the motor by a motor control apparatus. It is a flowchart which shows the calculation procedure of d-axis voltage command value and q-axis voltage command value.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Motor, 2 ... Resolver, 10 ... Motor control apparatus, 11 ... Current detection part, 12 ... Microcomputer, 51 ... d-axis voltage command value calculation part, 51c ... d-axis voltage estimation part, 51d ... d-axis correction value calculation , 51e ... d-axis correction unit, 52 ... q-axis voltage command value calculation unit, 52c ... q-axis voltage estimation unit, 52d ... q-axis correction value calculation unit, 52e ... q-axis correction unit, 61a ... multiplier, 61b ... Phase advance calculation unit, 61c: low-pass filter, 62a ... multiplier, 62b ... phase advance calculation unit, 62c ... low-pass filter, 63a ... deviation calculation unit, 63b ... multiplier, 64a ... deviation calculation unit, 64b ... multiplier, 65a ... Decoupling control correction unit, 65b ... Delay correction unit, 66a ... Decoupling control correction unit, 66b ... Delay correction unit

Claims (3)

Motor current detecting means for detecting a motor current flowing through the motor;
Basic voltage command value generating means for generating a basic voltage command value based on a deviation between a target current value and a motor current detected by the motor current detecting means;
Rotation angular velocity calculation means for calculating the rotation angular velocity of the motor;
A non-interacting control amount for calculating a non-interacting control amount for non-interacting control of the motor based on a motor current detected by the motor current detecting unit and a rotational angular velocity calculated by the rotational angular velocity calculating unit Computing means;
Motor voltage estimation means for estimating a motor voltage by performing a phase advance calculation on the motor current detected by the motor current detection means;
Correction value calculating means for calculating a correction value based on the estimated motor voltage estimated by the motor voltage estimating means and the basic voltage command value generated by the basic voltage command value generating means;
Correction means for correcting the basic voltage command value generated by the basic voltage command value generating means with the non-interacting control amount and the correction value to obtain a voltage command value;
A motor control device including drive means for driving the motor using the voltage command value obtained by the correction means.   The motor control device according to claim 1, wherein the phase advance calculation performed by the motor voltage estimating means is defined by a time constant of the motor.   3. The motor control device according to claim 1, wherein the correction value calculation unit obtains the correction value by multiplying a deviation between the estimated motor voltage and the basic voltage command value by a gain of 1 or less.

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