JP5390970B2 - Motor control device - Google Patents

Description

  The present invention relates to a motor control device.

  As this type of motor control device, for example, an arbitrary two-phase current value flowing through a three-phase winding and an electric angle of the rotor, the d-axis in the magnetic flux direction created by the magnetic field and q orthogonal to the d-axis The current value is converted into the dq coordinate of the axis, the current value of the d axis and the q axis is calculated, the current loop processing for performing the proportional integration operation etc. by taking the difference between the current value and the current command value for each axis is performed, and the d axis The voltage command value and the q-phase voltage command are calculated, the d-axis voltage command value and the q-axis voltage command value are converted into a three-phase voltage command value, and the motor is PWMed based on the three-phase voltage command value ( What controls (Pulse Width Modulation) is known (for example, refer patent document 1).

  The processing in the current loop includes an operation of integrating by taking the deviation between the current value and the current target value in each of the dq phases, and a combined vector of the d-axis voltage command value and the q-axis voltage command value. If the voltage exceeds the limit voltage that is limited in the system depending on the power supply voltage or the maximum duty ratio during PWM drive, etc., each axis current cannot be controlled according to each axis voltage command value, and the control deviation increases and the current loop As the absolute value of the integral value increases, the motor cannot be controlled normally.

Therefore, in the conventional motor control device, the d-axis voltage command value is obtained by clamping the q-axis current command value to a limit value that is the maximum value or the minimum value that can be taken at the current rotational speed of the motor. Consideration is given so that the integrated value in the integration calculation does not increase even if the combined vector of the q-axis voltage command value exceeds the limit voltage and is saturated.

JP 2008-67582 A

  Thus, in the conventional motor control device, it is necessary to control the motor while referring to the limiter value that clamps the q-axis current command value mapped in advance according to the specifications of the motor. When a different motor is controlled, it is necessary to prepare a map that is optimal for the motor or to redesign the control law, and there is a possibility that the control performance is reduced due to an error in specifications.

  Therefore, the present invention was devised to improve the above-mentioned problems, and the object of the present invention is to eliminate the saturation of the voltage command value without depending on the specifications of the motor, and to properly operate the motor. A motor control device that can be controlled is provided.

In order to achieve the above-described object, the problem solving means of the present invention obtains current values of the d-axis and the q-axis by using dq conversion that converts the motor drive current into dq orthogonal coordinates, and performs current loop processing for each axis. In a motor control device that performs vector control of the motor, determination means for determining the necessity of correction of the torque command, and input to the current loop when the determination means determines that correction of the torque command is necessary A correction unit for correcting the torque command, wherein the determination means has a combined vector of voltage command values for each axis of dq exceeding a limit voltage, and the output torque of the motor does not follow the torque command. Subject to, and determines that it is necessary to correct the torque command, the correction unit corrects the torque command based on the integrated value of the deviation of the length and the limit voltage of the composite vector And wherein the door.

  According to the motor control device of the present invention, the torque command is corrected without using any specifications of the motor, so even a motor having the same specifications has an error in specifications or a motor having completely different specifications is controlled. In this case, it is possible to eliminate the saturation of the combined vector of the d-axis voltage command value and the q-axis voltage command value without suppressing the design of the control law, and to suppress the integral saturation in the current loop, and always control the motor appropriately. And stable and good control results can be obtained.

It is a figure which shows an example of a structure of the motor control apparatus in one embodiment. It is a figure explaining the state where the synthetic | combination vector of the voltage command value of d axis | shaft and q axis | shaft exceeded the limiting voltage. It is a flowchart which shows an example of the process sequence which judges the saturation of the synthetic | combination vector in the motor control apparatus of one Embodiment. It is a figure which shows an example of a structure of the motor control apparatus in one modification of one Embodiment.

  The present invention will be described below based on the embodiments shown in the drawings. For example, as shown in FIG. 1, the motor control device 1 according to the embodiment controls the current flowing in the three-phase windings of the U, V, and W of the motor M to drive the motor M. Yes.

  Specifically, for example, as shown in FIG. 1, the motor control device 1 is a d-axis current command value id input from a higher-level control device (not shown) that controls a driven object (not shown) driven by the motor M. The d-axis voltage command calculation unit 2 that obtains the d-axis voltage command value Vd * based on * and the d-axis current value id, and the q-axis current command value iq * and the q-axis current value input from the control device q-axis voltage command calculation unit 3 for determining q-axis voltage command value Vq * based on iq, determination unit 4 as a determination unit for determining the necessity of correction of torque command, and the motor detected by current sensor 10 The current flowing in the two-phase winding of the three phases of M is converted from the electrical angle θ of the rotor in the motor M (not shown) detected by the position sensor 11 to the d-axis and q-axis currents of the dq orthogonal coordinate system, and d-axis Three-phase to obtain current value id and q-axis current value iq / The phase conversion unit 5, the correction unit 6 for correcting the q-axis current command value iq *, and the d-axis voltage command value Vd * and the q-axis voltage command value Vq * from the electrical angle θ of the rotor to U, V, W From the two-phase / three-phase converter 7 for converting the voltage command values Vu *, Vv *, Vw * of each of the three phases, from the U-phase voltage command value Vu, the V-phase voltage command value Vv, and the W-phase voltage command value Vw A PWM signal generator 8 that generates a PWM signal and an inverter circuit 9 that energizes the windings of the U, V, and W phases in the voltage direction and the duty ratio corresponding to the PWM signal are configured.

  In this case, the motor M is a three-phase brushless SPM motor (Surface Permanent Magnet Motor), and the torque output from the SPM motor is proportional to the q-axis current command value iq *, so the q-axis current command value iq * Is the torque command. In the normal control state, the d-axis current command value id * is set to 0 by the host controller, and when the field weakening control is performed, the d-axis current command value id * is set to an arbitrary negative value. Will be controlled.

  The motor control device 1 basically includes a d-axis current command value id * set by a host control device, a q-axis current command value iq * as a torque command, and a three-phase / two-phase conversion. Based on the deviations εd and εq from the d-axis and q-axis current values id and iq obtained as the calculation result of the unit 5, the motor M is proportionally integrated and controlled. Note that proportional differential integration control may be performed by adding an element obtained by differentiating the deviations εd and εq.

  In the above description, the host controller determines the d-axis current command value id * and the q-axis current command value iq * and inputs them to the motor controller 1. However, the motor controller 1 When a position loop, a speed loop, and a controller for controlling the motion of the driving target driven by the motor M are provided in the motor, the d-axis current command value id * and the q-axis current command value iq * It may be generated in the control device 1.

  Hereinafter, each part will be described in detail. The d-axis voltage command calculation unit 2 integrates the addition unit 2a that calculates a deviation εd between the d-axis current command value id * and the d-axis current value id, and integrates the deviation εd. And a proportional-integral operation unit 2b that calculates a d-axis voltage command value Vd * by adding a value obtained by multiplying the gain εd to the value obtained by multiplying the gain by a proportional gain. The d-axis current loop in the d-axis is configured by a loop including the d-axis voltage command calculation unit 2, the three-phase / two-phase conversion unit 5, the motor M, and the current sensor 10.

  Specifically, the deviation εd may be obtained by calculating a calculation formula of εd = id * −id. For the integration of the deviation εd, the integrated value is fd, and the integrated value of the d-axis calculated at the previous control is used. Assuming fdpre, the integrated value fd on the d-axis can be calculated by fd = fdpre + εd.

  Therefore, the d-axis voltage command value Vd * can be calculated as Vd * = KId · fd + KPd · εd, where KPd is the proportional gain and KId is the integral gain.

  The q-axis voltage command calculation unit 3 adds an addition unit 3a that calculates a deviation εq between the q-axis current command value iq * and the q-axis current value iq, and integrates the deviation εq and multiplies the integral gain to the deviation εq. And a proportional-integral operation unit 3b that calculates a q-axis voltage command value Vq * by adding a value obtained by multiplying the proportional gain. A loop composed of the q-axis voltage command calculation unit 3, the three-phase / two-phase conversion unit 5, the motor M, and the current sensor 10 constitutes a q-axis current loop.

  The q-axis voltage command value Vq * may be calculated in the same procedure as the d-axis voltage command value Vd *. Specifically, the deviation εq may be obtained by calculating a calculation formula of εq = iq * −iq. For the integration of the deviation εq, the integral value is fq, and the q-axis integral calculated during the previous control is used. If the value is fqpre, the integrated value fq on the q axis can be calculated by fq = fqpre + εq. Therefore, the q-axis voltage command value Vq * can be calculated as Vq * = KIq · fq + KPq · εq, where KPq is the proportional gain and KIq is the integral gain.

  The current sensor 10 may be a non-contact type using a Hall element, a winding, or the like, or a current sensor that obtains a current value from a voltage drop of a resistor that is serially connected to any two of three-phase windings. . The current sensor 10 only needs to detect a current value flowing in two phases of the U, V, and W phases. This is because the three-phase winding is delta-connected or Y-connected, and the two-phase current value is Is obtained, the three-phase / two-phase converter 5 uses the electrical angle θ of the rotor of the motor M to calculate the current values id and iq of the d- and q-axes from the current values of the two-phase windings. Because it is possible.

  The two-phase / three-phase converter 7 converts the d-axis voltage command value Vd * and the q-axis voltage command value Vq * into the actual voltage command values Vu *, Vv *, and Vw * for each U, V, and W phase. The converted voltage command values Vu *, Vv *, and Vw * for each phase are input to the PWM signal generator 8. The PWM signal generator 8 generates a PWM signal corresponding to the voltage command values Vu *, Vv *, Vw * and inputs it to the inverter circuit 9.

  Although not shown, the inverter circuit 9 includes, for example, a power source, three arms connected to the windings of each phase in the motor M, and two switching elements provided in each arm. The element is turned on / off according to the PWM signal generated by the PWM signal generator 8 and applied to the windings of each phase of the motor M at a duty ratio according to the voltage command values Vu *, Vv *, Vw *. In the present embodiment, since the motor M includes three-phase windings, the inverter circuit 9 includes three arms, which corresponds to the number of phases of the motor M windings. It only needs to have a number of arms.

  That is, in the case of the motor control device 1, the d-axis current command value id * and the q-axis current command value iq * given from the host control device are processed by the current loops of the corresponding axes in the normal state to control the motor M. It is supposed to be.

  Subsequently, the determination unit 4 determines the necessity of correction of the torque command. Specifically, it is determined whether or not the combined vector Vdq of the voltage command values Vd * and Vq * of the d-axis and the q-axis is saturated. The above determination is made based on the above. Specifically, in the determination by the determination unit 4, if the composite vector Vdq is not saturated in the previous determination, it is determined whether the composite vector Vdq is saturated in the current determination, and the composite vector Vdq is determined in the previous determination. Is saturated, it is determined at this time whether saturation of the combined vector Vdq is eliminated.

  If the combined vector Vdq is not saturated in the previous determination, the determination unit 4 compares the combined vector Vdq with the limit voltage Vlim to determine whether the combined vector Vdq exceeds the limit voltage Vlim. And the torque command and the output torque of the motor M are compared to check whether the output torque of the motor M follows the torque command.

  In this case, the motor M is an SPM motor, the torque command is given by the q-axis current command value iq *, and the torque of the motor M is proportional to the q-axis current value iq, so the q-axis current command value iq * and the q-axis The output value of the motor M follows the torque command by comparing the current value iq and determining whether or not the absolute value of the q-axis current command value iq * is larger than the absolute value of the q-axis current value iq. It can be determined whether or not.

  Then, as shown in FIG. 2, when the composite vector Vdq exceeds the limit voltage Vlim and the absolute value of the q-axis current command value iq * is larger than the absolute value of the q-axis current value iq, the composite It is determined that the vector Vdq is saturated and the torque command needs to be corrected. In other cases, it is determined that the combined vector Vdq is not saturated and the torque command need not be corrected.

  On the other hand, if it is determined in the previous determination that the combined vector Vdq is saturated, the determination unit 4 compares the q-axis current command value iq * and the q-axis current value iq in the current determination, When the absolute value of the q-axis current command value iq * is equal to or less than the absolute value of the q-axis current value iq, it is determined that saturation of the combined vector Vdq is eliminated and it is not necessary to correct the torque command. Then, the determination unit 4 outputs the determination result to the correction unit 6.

  The limit voltage Vlim is a voltage that is limited on the system depending on the power supply voltage, the maximum duty ratio in PWM driving, and the like. If the combined vector Vdq exceeds the limit voltage Vlim, basically, if the torque command exceeds the torque that the motor M can output at the current rotational speed, the output torque of the motor M will not follow the torque command. As described above, the absolute value of the q-axis current command value iq * is compared with the absolute value of the q-axis current value iq, and the absolute value of the q-axis current command value iq * is the absolute value of the q-axis current value iq. It is possible to determine that the torque command does not follow the output torque of the motor M by being larger.

  Note that, as described above, the determination unit 4 determines the follow-up state of the output torque to the torque command because the absolute value of the q-axis current command value iq * is larger than the absolute value of the q-axis current value iq. However, it is determined whether or not the output torque of the motor M follows the torque command by determining whether or not the q-axis current value iq is within the range within the q-axis current command value iq * ± threshold α. Can also be done. In this case, the threshold value α can be arbitrarily set, but is set to a difference between the q-axis current value iq and the q-axis current command value iq * that cannot be overlooked in the control. Furthermore, although the threshold value is set to the same value above and below the q-axis current command value iq *, different threshold values may be provided above and below the q-axis current command value iq *.

  Subsequently, for example, the correction unit 6 includes, for example, a calculation unit 6a that subtracts the limit voltage Vlim from the length L of the combined vector Vdq, an integration unit 6b that integrates the calculation result of the calculation unit 6a, and a calculation of the integration unit 6b. A gain multiplier 6c that multiplies the result by a gain and a deviation calculator 6d that calculates a deviation between the q-axis current command value iq * and the calculation result of the gain multiplier 6c are provided.

  The gain multiplier 6c includes two paths P1 and P2, one of which is a path P1 for multiplying a gain Kh set to an arbitrary positive value other than 0, and the other is a gain for multiplication. The path P2 is 0.

  Then, either one of the two paths in the gain multiplication unit 6c is selected and switched according to the determination result of the determination unit 4. Specifically, the determination result in the determination unit 4 is saturated. In this case, the path P1 to be multiplied by the gain Kh is selected, and when the determination result is not saturated (including the case where the saturation is released), the path P2 having the gain of 0 is selected.

  By configuring the correction unit 6 in this manner, when the determination unit 4 determines that the combined vector Vdq is saturated and the torque command needs to be corrected, the deviation calculation unit 6d receives 0 as a correction value. The q-axis current command value iq *, which is a torque command, is corrected based on the length L of the combined vector Vdq and the limit voltage Vlim, and the combined vector Vdq is saturated by the determination unit 4. If it is determined that the current value is not, 0 is input as the correction value to the deviation calculation unit 6d. As a result, the q-axis current command value iq * is not corrected and is input to the q-axis voltage command calculation unit 3 as it is. .

  In the above description, the two paths P1 and P2 are switched according to the determination result of the determination unit 4. However, when the combined vector Vdq is saturated, the correction value is simply set to 0, and the combined vector If Vdq is not saturated, a correction value may be calculated.

  When such correction is performed, for example, when the combined vector Vdq exceeds the limit voltage Vlim as shown in FIG. 2, the difference R between the length L of the combined vector Vdq and the limit voltage Vlim is obtained, and the difference R Therefore, the absolute value of the q-axis current command value iq *, which is a torque command, is corrected so as to be reduced. Therefore, the integrated saturation in the current loop can be eliminated together with the saturation of the combined vector.

  In other words, when the combined vector Vdq is not saturated, the current loop is directly used together with the d-axis current command value id * without correcting the q-axis current command value iq * which is a torque command given from the above-described upper control device. In the case where the normal control that is input and processed is performed, and the composite vector Vdq is saturated in light of the above conditions, it is determined that the torque command needs to be corrected and the SPM motor is controlled. The q-axis current command value iq * which is the torque command is corrected to cancel the saturation.

Further, the saturation of the combined vector Vdq with the output torque of the motor M following the torque command, in this case, the q-axis current value iq following the q-axis current command value iq *. Is determined by feeding back the difference R between the length L of the combined vector Vdq and the limit voltage Vlim, and correcting the q-axis current command value iq * which is a torque command. Even though the q-axis current value iq corresponding to the output torque does not follow the q-axis current command value iq * which is a torque command, the combined vector Vdq may dynamically fall within the limit voltage Vlim. There, as described above, so as to recognize the elimination of saturation of the resultant vector Vdq by determining the principal unnecessary correction of the torque command, that is this to be necessary to correct the torque command will be interrupted It can avoid, it is possible to eliminate the saturation of reliably resultant vector Vdq.

  In addition, in the determination unit 4 that is a determination means, not only the combined vector Vdq of the voltage command values Vd * and Vq * of each axis of dq exceeds the limit voltage Vlim, but the output torque of the motor M follows the torque command. If it is determined that the combined vector Vdq is saturated on the condition that the torque command is not corrected, it is determined that the torque command needs to be corrected. However, it is possible to avoid performing the control to correct the torque command only when the composite vector Vdq exceeds the limit voltage Vlim dynamically or temporarily, and in such a case, the normal control is performed. Priority can be given to obtain good controllability.

  Although the difference R between the length L of the combined vector Vdq and the limit voltage Vlim can be fed back by a proportional operation to correct the q-axis current command value iq *, which is a torque command, the integration operation ensures that In addition, the saturation of the synthesized vector Vdq can be quickly eliminated.

  And according to the motor control apparatus 1, since the specifications of the motor M are not used at all for the above correction, even a motor having the same specifications has an error in the specifications or a motor having completely different specifications is controlled. In this case, it is possible to eliminate the saturation of the combined vector Vdq and suppress the integral saturation in the current loop without any design change of the control law, and to always control the motor appropriately, and to achieve a stable and good control result. Can be obtained.

  Further, the motor control device 1 includes, for example, a CPU (Central Processing Unit) as a hardware configuration, a main storage device such as a RAM (Random Access Memory) that provides a storage area for the arithmetic processing device, and the like. And a secondary storage device such as a ROM (Read Only Memory) or an HD (Hard Disk) in which a program used for the above processing is stored. Each part other than the current sensor 10, the position sensor 11, the PWM signal generator 8, and the inverter circuit 9 is realized.

  Although not shown, a D / A converter that converts analog signals output from the position sensor 11 and the current sensor 10 into digital signals, an arithmetic processing device, a main storage device, a secondary storage device, a D / A converter, and an inverter An interface device for connecting the circuit is separately provided.

  Here, the processing procedure in the determination regarding the necessity of correction of the torque command in the motor control apparatus 1 described above will be described based on the flowchart shown in FIG.

  First, in step S1, the motor control device 1 determines whether or not the torque command has been corrected at the time of the previous control, that is, whether or not the combined vector Vdq is saturated, based on the correction flags On and Off. To do. If the correction flag is On, it is determined that the torque command has been corrected during the previous control, and the process proceeds to step S2. Conversely, if the correction flag is Off, the torque command is corrected during the previous control. Therefore, it is determined that the combined vector Vdq is not saturated, and the process proceeds to step S6.

  In step S2, since the torque command is corrected at the time of the previous control, the motor control device 1 indicates that the absolute value of the q-axis current command value iq *, which is the torque command, indicates the output torque of the motor M. The absolute value of the q-axis current value iq is compared. When the absolute value of the q-axis current command value iq * is larger than the absolute value of the q-axis current value iq, the composite vector Vdq has not left the saturated state during the current control following the previous control, and the torque command When the absolute value of the q-axis current command value iq * is less than or equal to the absolute value of the q-axis current value iq, the resultant vector Vdq is saturated during the current control. It is determined that the torque command is not corrected, and the process proceeds to step S3.

  In step S3, since the saturation of the combined vector Vdq has been eliminated and no correction of the torque command is necessary, the motor control device 1 sets the correction flag to Off and the q-axis current command value iq * that is the torque command. The correction value for correcting is set to 0 (step S4).

  On the other hand, in step S5, since the saturation of the combined vector Vdq is not eliminated and the torque command needs to be corrected, the correction value for correcting the q-axis current command value iq * is set to the length L of the combined vector Vdq and the limit voltage. Obtained based on the difference R of Vlim.

If it is determined in step S1 that correction of the torque command is unnecessary during the previous control and the process proceeds to step S6, the motor control device 1 indicates that the combined vector Vdq exceeds the limit voltage Vlim, and Then, it is determined whether or not the two conditions that the absolute value of the q-axis current command value iq * exceeds the absolute value of the q-axis current value iq are satisfied.

Then, if it meets both conditions, this resultant vector Vdq is not saturated is determined to be necessary to correct the torque command, the process proceeds to step S7, the motor control device 1 sets the correction flag to On Then, the process proceeds to step S5 to calculate a correction value for correcting the q-axis current command value iq *.

  On the other hand, if both conditions are not satisfied in step S6, the combined vector Vdq is not saturated at the time of the current control following the previous control, and no correction of the torque command is required. A correction value for correcting a certain q-axis current command value iq * is set to 0 (step S8).

  The motor control device 1 controls the motor M by repeatedly performing the above steps S1 to S8. That is, when the motor control device 1 executes the above-described series of processing, the processing of each unit in the determination unit 4 and the correction unit 6 described above is realized. Although not shown, in parallel with this process, the d-axis voltage command calculation unit 2, the q-axis voltage command calculation unit 3, the three-phase / two-phase conversion unit 5, and the two-phase / three-phase conversion unit 7 Processing is performed.

  In the above description, the determination unit 4 compares the combined vector Vdq with the limit voltage Vlim, and the correction unit 6 uses the difference R between the length L of the combined vector Vdq and the limit voltage Vlim. Although the correction value is calculated, a route calculation is included in which the values obtained by squaring the values of Vd * and Vq * in the above comparison and calculation are halved. In general, it takes time to execute route calculation in an arithmetic processing unit, but it is necessary to perform the above calculation at high speed in order to perform motor current control. Use is forced and the motor control apparatus 1 becomes expensive. Therefore, the determination in the determination unit 4 and the correction unit 6 compares the value obtained by squaring the length L of the combined vector Vdq with the value obtained by squaring the limit voltage Vlim, and the value obtained by squaring the length L of the combined vector Vdq and the limit voltage. By calculating a correction value for correcting the q-axis current command value iq * based on the difference from the squared value of Vlim, route calculation can be avoided, and an inexpensive calculation processing device is used. In addition, the motor current can be sufficiently controlled.

  In this case, if the q-axis current command value iq * is corrected by feeding back the difference between the value obtained by squaring the length L of the combined vector Vdq and the value obtained by squaring the limit voltage Vlim, the control characteristic becomes nonlinear. By tuning the gain Kh, it is possible to perform control with no practical problem.

  In the above description, the motor M is an SPM motor. However, when an IPM motor (Interior Permanent Magnet Motor) is controlled, a reluctance torque can be used in addition to a magnet torque. A d-axis current command value id * and a q-axis current command value iq * that can output torque are obtained. Specifically, for example, in the control of the IPM motor, a control method such as maximum torque control is used, and the torque command in the IPM motor is determined according to the current phase angle at which the total torque of the magnet torque and the reluctance torque is maximized. It is converted into a d-axis current command value id * and a q-axis current command value iq * and input to the current loop of each axis.

  Therefore, when controlling the IPM motor, the configuration and operation of the determination unit and the correction unit may be changed to be suitable for the IPM motor.

  Specifically, as shown in FIG. 4, the motor control device 21 that is suitable for the IPM motor has a d-axis current command value id * and a q-axis current command value iq * from a torque command input from a host control device (not shown). And a d-axis voltage command calculation unit 2 for determining a d-axis voltage command value Vd * based on the d-axis current command value id * and the d-axis current value id, and the control device described above. A q-axis voltage command calculation unit 3 for obtaining a q-axis voltage command value Vq * based on a q-axis current command value iq * and a q-axis current value iq, which is one of torque commands input from In the determination unit 22 as a determination means for determining the necessity of correction, and in the motor M (not shown) in which the current flowing in the two-phase winding of the three phases of the motor M detected by the current sensor 10 is detected by the position sensor 11. Dq orthogonal seat from electrical angle θ of rotor The three-phase / two-phase conversion unit 5 that converts the d-axis current value id and the q-axis current value iq by converting the current into the d-axis and q-axis currents of the system and the torque command input to the maximum torque control unit 24 The correction unit 23 converts the d-axis voltage command value Vd * and the q-axis voltage command value Vq * into voltage command values Vu *, Vv *, Vw * for three phases U, V, W from the electrical angle θ of the rotor. Corresponding to PWM signal, two-phase / three-phase converter 7 for converting to PWM, PWM signal generator 8 for generating PWM signal from U-phase voltage command value Vu, V-phase voltage command value Vv and W-phase voltage command value Vw, and PWM signal And an inverter circuit 9 for energizing the windings of the U, V, and W phases in the voltage direction and the duty ratio. In addition, about the component similar to the motor control apparatus 1 in one Embodiment mentioned above, since the same operation | movement is exhibited, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  Therefore, the motor control device 21 in one modification of the embodiment suitable for controlling the motor M ′ that is an IPM motor is different from the motor control device 1 in the embodiment in the determination unit 22 and the correction unit 23. is there.

  Similar to the determination unit 4, the determination unit 22 determines whether the torque command needs to be corrected by checking whether or not the combined vector Vdq is saturated. Similar to the determination unit 4, the synthesized vector Vdq and the limit voltage Vlim are compared to determine whether the synthesized vector Vdq exceeds the power supply voltage Vlim as one of the determination materials. As another determination material, whether the output torque of the motor M ′ follows the torque command or not is determined because the output torque of the motor M ′ is not proportional to the q-axis current value iq. It cannot be judged only by comparing iq with the q-axis current command value iq *.

  Therefore, in the determination unit 22 in the motor control device 21, the d-axis current value id is controlled in accordance with the d-axis current command value id *, and the q-axis current value iq is in accordance with the q-axis current command value iq *. In the case where the output torque is controlled to the torque command, attention is paid to the fact that the output torque of the motor M ′ follows the torque command, and the deviation εd between the d-axis current command value id * and the d-axis current value id, which is the torque command, The absolute value of the value obtained by adding the deviation εq between the q-axis current command value iq * and the q-axis current value iq is smaller than the threshold value β that is set to a value that can be overlooked in the control. It is determined that the output torque of the motor M ′ follows. By making such a determination, it is determined whether or not the resultant vector Vdq is saturated without using the torque characteristics of the motor M ′ that must depend on the specifications of the motor M ′ that is an IPM motor. can do.

  The determination in the determination unit 22 can be realized by performing the same processing as the processing in the determination of the motor control device 1 of the embodiment. Therefore, the processing related to the determination in the motor control device 21 is changed as follows in the processing in step S2 and the processing in step S6 in the processing procedure in the motor control device 1 of the embodiment shown in FIG. That's fine.

  Specifically, in the motor control device 22, the process in step S2 of FIG. 3 is replaced with a determination whether the absolute value of the value obtained by adding the deviation εd and the deviation εq is smaller than the threshold value β. If the absolute value of the value obtained by adding εd and deviation εq is smaller than the threshold value β, the combined vector Vdq is not saturated, so the process proceeds to step S3. Conversely, the absolute value of the value obtained by adding the deviation εd and deviation εq is If it is greater than or equal to the threshold value β, the combined vector Vdq is saturated, and the process may proceed to step S5.

  Further, the motor control device 22 adds the deviation εd and the deviation εq to determine whether the q-axis current command value iq * during the process of step S6 in FIG. 3 is larger than the q-axis current value iq. This can be replaced with a determination as to whether or not the absolute value of the obtained value is smaller than the threshold value β.

  Subsequently, when the combined vector Vdq is saturated and the torque command needs to be corrected, the correcting unit 23 determines the length L of the combined vector Vdq and the limit voltage Vlim in the same manner as the correcting unit 6 in the embodiment. Based on the difference R, the correction value C is calculated.

  Specifically, for example, the correction unit 23 subtracts the limit voltage Vlim from the length L of the combined vector Vdq to obtain a difference R, and an integration unit 23b that integrates the calculation result of the calculation unit 23a. And a gain multiplication unit 23c that multiplies the calculation result of the integration unit 23b by a gain, and calculates a deviation between the torque command and the calculation result of the gain multiplication unit 23c to correct the torque command before being input to the maximum torque control unit 24. And a deviation calculating unit 23d.

  The gain multiplication unit 23c includes two paths P1 and P2. One is a path P1 that multiplies a gain Kh set to an arbitrary positive value other than 0, and the other is a multiplication. When the determination result that the gain is 0 and the combined vector Vdq is saturated is input by the determination unit 22, the path P1 is selected, and the determination result that the combined vector Vdq is not saturated is obtained. When input, the path P2 is selected. The gain may be multiplied after the distribution value is distributed to the d-axis and the q-axis in the distribution calculation unit 23d.

  Further, as described above, the maximum torque control unit 24 causes the motor M ′ to output torque in accordance with the torque command input from the host controller, and the current phase angle at which the total torque of the magnet torque and the reluctance torque is maximized. Thus, the d-axis current command value id * and the q-axis current command value iq * are obtained.

  Thus, in the motor control device 21 in this modified example, when the combined vector Vdq is saturated, the torque command is corrected, the saturation of the combined vector Vdq is canceled, and the integrated saturation in the current loop of each axis is also suppressed. . In addition, since the motor control device 21 does not use the specifications of the IPM motor in correcting the torque command, a motor having the same specifications as the motor control device 1 according to the embodiment has an error in the specifications. When controlling a motor with different specifications or a motor with completely different specifications, it is possible to eliminate the saturation of the composite vector Vdq and suppress the integral saturation in the current loop without changing the design of the control law. Therefore, stable and good control results can be obtained.

  This is the end of the description of the embodiment of the present invention, but the scope of the present invention is of course not limited to the details shown or described.

  The present invention is applicable to a control device that controls a motor.

1,21 Motor control device 2 d-axis voltage command calculation unit 2a addition unit 2b in d-axis voltage command calculation unit proportional integral calculation unit 3 in d-axis voltage command calculation unit q-axis voltage command calculation unit 3a in q-axis voltage command calculation unit Adder 3b Proportional integral calculator 4 in q-axis voltage command calculator 4, 22 Judgment unit 5 Three-phase / two-phase converter 6, 23 Correction unit 6a, 23a Calculation unit 6b in correction unit 23b Integration unit 6c in correction unit 23c Gain multiplication unit 6d in the correction unit, Deviation calculation unit 7 in the correction unit 7 Two-phase / three-phase conversion unit 8 PWM signal generator 9 Inverter circuit 10 Current sensor 11 Position sensor M, M ′ Motor P1, P2 Path in the correction unit

Claims (6)

Correction of torque command in a motor control device that performs vector loop control of a motor by obtaining current values of d-axis and q-axis using dq conversion that converts motor drive current into dq orthogonal coordinates and performing current loop processing for each axis And a correction unit that corrects the torque command input to the current loop when the determination unit determines that the torque command needs to be corrected. The determination unit includes dq It is determined that the torque command needs to be corrected on condition that the combined vector of the voltage command values for each axis exceeds the limit voltage and the output torque of the motor does not follow the torque command. The correction unit corrects the torque command based on an integral value of the length of the combined vector and the deviation of the limit voltage. The determination means determines that no correction of the torque command is necessary on the condition that the output torque of the motor follows the torque command after starting the correction of the torque command, and stops the correction of the torque command. The motor control device according to claim 1 . The correction unit includes a calculation unit that obtains the deviation of the combined vector length and the limit voltage, an integration unit that integrates a calculation result of the calculation unit, and a gain multiplication unit that multiplies the calculation result of the integration unit by a gain, The motor control device according to claim 1, wherein the torque command is corrected using a calculation result of the gain multiplication unit. The gain multiplication unit selects a gain that is set to any positive value other than 0 when the determination result of the determination means requires correction of the torque command, and the determination result of the determination means is the torque 4. The motor control device according to claim 3, wherein a gain set to 0 is selected when command correction is unnecessary. The determination means compares the square value of the combined vector length of the voltage command value for each axis of dq with the square value of the limit voltage, and the combined vector of the voltage command value for each axis of dq is the limit voltage. Whether the torque command needs to be corrected or not, and corrects the torque command based on the integrated value of the deviation between the square value of the combined vector length and the square value of the limit voltage. The motor control device according to claim 1, wherein the motor control device is a motor control device. When the motor is an IPM motor and the torque command is distributed to the d-axis current command value and the q-axis current command value, the determination means determines the deviation between the d-axis current command value and the d-axis current value and the q-axis 6. The motor according to claim 1, wherein it is determined whether or not the output torque of the motor follows the torque command based on a deviation between a current command value and a q-axis current value. Control device.

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