Motor control device

Abstract

The motor control device (1) drives the motor (5) through the inverter (4). The motor control device (1) is provided with a processor. A processor (a harmonic magnetic flux command value calculation unit (8)) calculates a harmonic magnetic flux command value phi * dqh on the basis of a current command value i * dq (dq-axis current command value (2)) and an electrical angle theta e of a motor. A processor (FF voltage calculation unit (9)) calculates an FF voltage command value v * dqh, which represents a feed-forward voltage command value including a component corresponding to a voltage drop caused by a resistance R of a motor, on the basis of an electrical angular velocity [omega] e of the motor and a harmonic magnetic flux command value [phi] * dqh. A processor (voltage command superimposing unit (10)) superimposes an FF voltage command value v * dqh on a voltage command value v * dq. As a result, it is possible to improve torque ripple suppression accuracy.

Description

Technical Field

[0001] The invention relates to a motor control device. Background Art

[0002] To meet the needs of applications with limited loading space, such as automobiles, electric motors are becoming increasingly dense in terms of output. Consequently, electric motors are increasingly being used in the magnetic saturation region. In this region, torque ripple increases, causing vibration and noise, necessitating torque ripple suppression control.

[0003] During torque ripple suppression control, harmonic currents flow to generate torque with a phase opposite to the generated torque ripple. Generally, the methods for generating harmonic currents differ between low and high rotational speed ranges. In the low rotational speed range, harmonic currents are generated by superimposing harmonic current command values ​​on the current command values, using current FB (feedback). However, in the high rotational speed range, where the frequency of the harmonics exceeds the frequency band of current FB, accurate harmonic currents cannot flow.

[0004] Therefore, the required inverter output voltage is directly calculated based on the harmonic current command values, allowing the harmonic currents to flow through the motor. Calculating the necessary voltage command based on the harmonic current command values ​​requires an inverse model of the motor. The accuracy of the harmonic current calculation depends on the accuracy of the inverse model. For example, the inverse model used in Patent Document 1 takes into account the effects of the motor's inductance, resistance, and induced voltage. It calculates the voltage command value based on the harmonic current command values, achieving sufficient accuracy without the influence of magnetic saturation. Prior art literature Patent Literature

[0005] Patent Document 1: Japanese Patent No. 5574790 Summary of the Invention Problems to be solved by the invention

[0006] In order to realize desired high-order harmonic currents with high accuracy in the magnetic saturation region, the required motor inverse model requires a large amount of storage space and calculation times.

[0007] An object of the present invention is to provide a motor control device capable of improving the accuracy of suppressing torque ripple. Technical means to solve the problem

[0008] In order to achieve the above-mentioned purpose, the present invention provides a motor control device, which drives a motor through an inverter. The motor control device includes a processor, which calculates a higher harmonic flux command value based on a torque command value or a current command value and the electrical angle of the motor, calculates an FF voltage command value based on the electrical angular velocity of the motor and the higher harmonic flux command value, and superimposes the FF voltage command value on the voltage command value. The FF voltage command value represents a feedforward voltage command value that includes a component corresponding to the voltage drop caused by the resistance of the motor. Effects of the Invention

[0009] According to the present invention, it is possible to improve the accuracy of suppressing torque ripple. Other problems, configurations, and effects than those described above will become clear from the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic block diagram of a motor control device according to the first embodiment of the present invention. Figure 2 This is a diagram explaining the conversion from current to magnetic flux. Figure 3 This is a schematic block diagram of a motor control device according to a second embodiment of the present invention. Figure 4 This is a schematic diagram showing how the dominant term changes depending on the rotational speed. DETAILED DESCRIPTION

[0011] Hereinafter, the configuration of the motor control device according to Embodiments 1 to 4 of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals denote the same parts.

[0012] (Example 1) Figure 1 This is a functional block diagram showing the configuration of a motor control device according to the first embodiment of the present invention.

[0013] In the following description, "dq axis" means "d axis and q axis". In addition, for the parameter X with a subscript (such as "i" or "v") in the following description, "X dq " indicates "vector quantity (X d , X q )","X uvw " indicates "vector quantity (X u , X v , X w ). Here, "uvw" represents the three phases of AC, namely "U phase, V phase, and W phase."

[0014] The motor control device 1 controls the speed and torque of the motor 5 by controlling the switching of the inverter 4 that supplies AC power to the motor 5 .

[0015] In this embodiment, the motor control device 1 is composed of a processing unit such as a microcomputer, a gate driver, etc. The processing unit includes a processor, a memory, an input / output circuit, etc., and functions as each unit by executing a predetermined program.

[0016] In the present embodiment, the inverter 4 is a three-phase inverter having a three-phase full-bridge circuit constituted by semiconductor switching elements such as IGBTs and MOSFETs as a main circuit.

[0017] In this embodiment, as the motor 5 , a three-phase AC synchronous motor as a rotating machine, for example, a permanent magnet synchronous motor is used.

[0018] The motor 5 is not limited to a synchronous machine, and an induction machine can also be applied. In addition, the motor 5 is not limited to a rotary machine, and a linear motor can also be applied. In addition, the motor 5 can also have a power generation function.

[0019] like Figure 1 As shown, the motor control device 1 includes: dq axis current command value 2 (i * dq ), voltage command operation unit 3, electric angle detection unit 6, electric angular velocity operation unit 7 (electric angular velocity calculation unit), higher harmonic flux command value operation unit 8, FF voltage operation unit 9, voltage command superposition unit 10, voltage command value dq / three-phase axis converter 11, measured current three-phase / dq axis converter 12.

[0020] The dq axis current command value 2 is calculated as the dq axis current required to output the torque of the torque command given by the motor. Generally, it is determined so that the torque output per unit current is maximum (MTPA), but the present invention is effective for any current.

[0021] The voltage command calculation unit 3 is based on the dq axis current detection value i dq and dq axis current command value i * dq The difference between the two generates the voltage command value v * dq , so that i dq with i * dq consistent.

[0022] In this embodiment, the voltage command calculation unit 3 has a known configuration. For example, it may be composed of a dq-axis current controller that generates dq-axis voltage command values ​​using a PI calculation. Alternatively, the dq-axis voltage command values ​​may be generated using a known voltage equation, instead of a PI calculation.

[0023] The electrical angle detection unit 6 calculates and outputs the electrical angle θ based on a rotation position signal from a rotation sensor (not shown) provided in the motor 5.e The rotation sensor is based on the mechanical angle (θ m ) outputs a rotation position signal, but the electrical angle detection unit 6 uses the number of pole pairs (p) of the motor 5 and θ e ,θ m and p(θ e =p·θ m ), calculate θ e .

[0024] As the rotation sensor, a mechanical angle resolver, a Hall sensor, a rotary encoder, etc. can be used. Alternatively, a configuration in which the electrical angle is estimated from the current or voltage using a general position sensorless control method may be employed.

[0025] The electrical angular velocity calculation unit 7 calculates the electrical angular velocity ω based on the rotation position signal from the rotation sensor (not shown) provided in the motor 5, similarly to the electrical angle detection unit 6 (electrical angle calculation unit). e The electrical angular velocity calculation unit 7 uses the number of pole pairs (p) of the motor 5 and the electrical angle θ e and mechanical angle θ m and p(θ e =p·θ m ) and θ e and ω e The relationship (ω e =dθ e / dt) to calculate ω e In addition, the electrical angular velocity calculation unit 7 may also calculate the θ output by the electrical angle detection unit 6. e Differentiate to calculate ω e The differentiator composition.

[0026] The higher harmonic flux command value calculation unit 8 calculates the value of the harmonic flux command value based on i * dq and electrical angle θ e Calculate and output the higher harmonic flux command value φ * dqh φ * dqh You can use i * dq and high-order harmonic current command i * dqh Calculated by formula (2), it can also be used as the i input to the motor 5 in advance * dq and θ e The corresponding value is stored. In addition, it can also replace i * dq As the torque command value and θ eBy using the torque command as an argument, the size of the table can be reduced under the MTPA condition where the torque command and the current command correspond one to one.

[0027] [Formula 1]

[0028] [Formula 2]

[0029] Among them, f in formula (2) d The relationship between current and magnetic flux is obtained through prior analysis or experiments, such as Figure 2 As shown, it is a function that depends on the current of the dq axis.

[0030] The FF voltage calculation unit 9 is based on the higher harmonic flux command value φ * dqh and electrical angular velocity ω e , calculate and output FF voltage v based on formula (1) * dqh Among them, L in formula (1) dq and L qd represents the interference inductance between the dq axes, K edh and K eqh Indicates the d-axis and q-axis higher harmonic components in the magnet flux.

[0031] According to the constants of the motor, the constants with small effects can be ignored. For example, L dq and L qd Usually than L d and L q It is much smaller and therefore can be ignored.

[0032] Here, we will explain how the influence of magnetic saturation can be taken into account by using equation (1), thereby improving the accuracy of generating the FF voltage command. The inverse model of the motor taking magnetic saturation into account is equation (3).

[0033] [Formula 3]

[0034] However, the variable with t added to the end of the subscript L representing inductance represents dynamic inductance, and the variable without t represents static inductance. Static inductance is a value determined by the ratio of the dq axis current to the dq axis magnetic flux, and dynamic inductance refers to the ratio of change in magnetic flux near the current that serves as the reference. In the absence of magnetic saturation, the dynamic inductance and the static inductance are consistent, but in the presence of magnetic saturation, the dynamic inductance and the static inductance are inconsistent, which manifests as an error in the voltage command. In the present invention, this error is suppressed by considering static and dynamic inductances, thereby improving the accuracy in the magnetic saturation region. When using formula (3) to calculate voltage from current, 8 inductance tables and 2 induced voltage constant tables are required (the inductance table is a two-dimensional mapping relative to the dq axis current value), which increases the storage capacity and calculation load. Here, the relationship formula (5) between magnetic flux and dynamic inductance defined by formula (4) is used.

[0035] [Formula 4]

[0036] [Formula 5]

[0037] By modifying Equation (3) using Equations (4) and (5) and extracting only the higher harmonic components, we obtain Equation (1). Comparing Equations (1) and (3), by calculating the voltage based on the magnetic flux, a table for dynamic inductance is no longer necessary. This allows for highly accurate calculation of the FF voltage command value with fewer variables and fewer table searches (computational load) than when calculating the FF voltage command value based on the higher harmonic current command value.

[0038] The voltage command superposition unit 10 outputs a voltage command value v ** dq , the voltage command value v ** dq The voltage command value v output from the voltage command calculation unit 3 is * dq The FF voltage command value v calculated by the FF voltage calculation unit 9 is superimposed. * dqh And get it.

[0039] The voltage command value dq / three-phase axis converter 11 is based on θ e The voltage command value v output from the voltage command superposition unit 10 is ** dq The voltage is converted into a three-phase voltage to generate a signal for controlling the switch of the inverter 4. A θ-axis which compensates for the delay until the voltage command value is actually reflected in the inverter may be used. ec Instead of θ e .

[0040] The current three-phase / dq axis converter 12 is measured according to θe Convert the three-phase current detected by the current sensor into dq axis current i dq You can also use θ which takes into account the current detection delay. ed Instead of θ e .

[0041] The main features of Example 1 can also be summarized as follows.

[0042] The motor control device 1 drives the motor 5 via the inverter 4. The motor control device 1 includes a processor. Figure 1 As shown, the processor (higher harmonic flux command value calculation unit 8) calculates the current command value i based on the current command value i * dq (dq axis current command value 2) and the motor electrical angle θ e , calculate the higher harmonic flux command value φ * dqh The processor (FF voltage calculation unit 9) calculates the electric angular velocity ω of the motor based on the electric angular velocity ω of the motor. e and higher harmonic flux command value φ * dqh , calculate the FF voltage command value v * dqh , the FF voltage command value v * dqh The processor (voltage command superimposing unit 10) generates a voltage command value v that includes a component corresponding to the voltage drop caused by the resistance R (winding resistance) of the motor. * dq The FF voltage command value v is superimposed on * dqh .

[0043] The FF voltage command value includes a component corresponding to the voltage drop caused by the motor resistance R, thereby improving the accuracy of the FF voltage command value. As a result, the accuracy of suppressing torque ripple can be improved.

[0044] The processor (voltage command calculation unit 3) calculates the current command value i * dq (dq axis current command value 2) and measured current value (dq axis current i dq )Calculate the voltage command value v * dq .

[0045] In this embodiment, the three-phase current supplied from the inverter 4 to the motor 5 is controlled by performing feedback control so that the measured current value matches the current command value.

[0046] For the motor resistance R, d-axis inductance L d , q-axis inductance L q , the interference inductance L between the d-axis and the q-axisdq , L qd 、The higher harmonic component K of the magnet flux on the d-axis edh , the higher harmonic component K of the magnet flux on the q axis eqh , d-axis higher harmonic flux command value φ * dh , q-axis higher harmonic flux command value φ * qh , electrical angular velocity ω e The processor (FF voltage calculation unit 9) calculates the FF voltage command value v according to formula (1) * dqh In addition, s in formula (1) is the Laplace operator.

[0047] By calculating the FF voltage command value using equation (1), the accuracy of the FF voltage command value is improved even in the high-torque region where magnetic saturation occurs. Furthermore, by reducing the number of motor constants used, the number of times the motor constant table is searched is reduced. Consequently, computing resources can be saved.

[0048] That is, the processor (FF voltage calculation unit 9 ) calculates the FF voltage command value using a motor inverse model based on magnetic flux.

[0049] By using a motor inverse model based on magnetic flux, it is possible to reduce motor constants used in calculating the FF voltage command value.

[0050] The processor (FF voltage calculation unit 9) does not use the dynamic inductance L dt , L qt , L dqt , L qdt The table uses 4 static inductors (the inductance of the d-axis L d , q-axis inductance L q , the interference inductance L between the d-axis and the q-axis dq , L qd ) table and two induced voltage constants (higher harmonic components of the magnet flux of the d-axis K edh , the higher harmonic component K of the magnet flux on the q axis eqh ) table, calculate the FF voltage command value v * dqh .

[0051] By not needing to retrieve the dynamic inductance L dt , L qt , L dqt , L qdt The table can speed up the calculation of the FF voltage command value and save computing resources.

[0052] The processor (FF voltage calculation unit 9 ) calculates a component corresponding to the voltage drop caused by the resistance R (winding resistance) of the motor based on the first term of the equation (1).

[0053] As a result, the accuracy of the FF voltage command value is improved in the low-speed region and the low-speed and low-torque region.

[0054] (Example 2) use Figure 3 The block diagram of this embodiment shows the difference from the embodiment 1. This embodiment includes a converter 100 and a converter 101, and calculates a second magnetic flux command value φ by adding a harmonic magnetic flux command value to the output of the magnetic flux command value of the converter 100. ** dq The converter 100 calculates the current command value (dq axis current command value 2) by the current command value calculation unit 21 according to the torque command value 20, converts the current command value into a flux command value, and the converter 101 converts the measured current into a measured flux value. Furthermore, the voltage command calculation unit 3 calculates the voltage command value v according to the second flux command value and the flux measurement value. * dq The harmonic flux command value calculation unit 8 pre-records the harmonic flux command value φ obtained by using the formula (2) based on the harmonic current command value corresponding to the torque command value. * dqh , directly outputting the higher harmonic flux command value according to the torque command value during control. In this configuration, converter 100 and converter 101 can be the same function. In the case of a table, tables with different resolutions can also be used depending on the required accuracy of the command value and the measured value.

[0055] The operation of the second embodiment will be described in comparison with the first embodiment. By using the second magnetic flux command value φ ** dq , it is possible to prevent the high-order harmonic current superimposed by the FF voltage command from being suppressed by the FB loop. Furthermore, the input physical quantity of the voltage command calculation unit 3 is converted into magnetic flux by the converter 100, and it is no longer necessary to calculate the high-order harmonic current. Therefore, only the high-order harmonic magnetic flux command value φ is recorded. * dqh Of course, even if a configuration without converter 100 is adopted, the interference between FB (feedback) and FF (feedforward) can be suppressed by superimposing the harmonic current command value on the current command value and calculating the FF voltage command based on the harmonic flux command value.

[0056] The main features of Example 2 can also be summarized as follows.

[0057] The motor control device 1 drives the motor 5 via the inverter 4. The motor control device 1 includes a processor. Figure 3As shown, the processor (higher harmonic flux command value calculation unit 8) calculates the torque command value 20 (τ * ) and the electrical angle θ of the motor e , calculate the higher harmonic flux command value φ * dqh The processor (FF voltage calculation unit 9) calculates the electric angular velocity ω of the motor based on the electric angular velocity ω of the motor. e and higher harmonic flux command value φ * dqh , calculate the FF voltage command value v * dqh , the FF voltage command value v * dqh The processor (voltage command superimposing unit 10) generates a voltage command value v that includes a component corresponding to the voltage drop caused by the resistance R (winding resistance) of the motor. * dq The FF voltage command value v is superimposed on * dqh .

[0058] The FF voltage command value includes a component corresponding to the voltage drop caused by the motor resistance R, thereby improving the accuracy of the FF voltage command value. As a result, the accuracy of suppressing torque ripple can be improved.

[0059] The processor (voltage command calculation unit 3) calculates the voltage based on the current command value i * dq (dq-axis current command value 2) converted into the first magnetic flux command value φ * dq And from the measured current value (dq axis current i dq ) The measured magnetic flux value φ converted dq , calculate the voltage command value v * dq .

[0060] For example, feedback control may be used to control the three-phase current supplied from the inverter 4 to the motor 5 so that the measured magnetic flux value matches the first magnetic flux command value. However, feedback control suppresses the higher harmonic current superimposed by the FF voltage command.

[0061] Therefore, if Figure 3 As shown, the processor (voltage command calculation unit 3) generates a voltage command based on the first magnetic flux command value φ. * dq The high-order harmonic flux command value φ is superimposed on * dqh The second magnetic flux command value φ ** dq And the measured magnetic flux value φ dq Calculated voltage command value v * dq.

[0062] In this embodiment, by performing feedback control so that the measured magnetic flux value coincides with the second magnetic flux command value, interference between the feedback control and the feedforward control can be suppressed.

[0063] (Example 3) This embodiment adopts the following structure: as in the second embodiment, a higher harmonic flux command value calculation unit is provided that calculates and records the flux command value in advance, and the higher harmonic flux command value is stored in the form of amplitude and phase for each order of the electrical angle. Formula (1) includes the differential of the flux command value. In the case of flux command values ​​that are not separated by order, a delay is generated due to the calculation of the differential. On the other hand, for higher harmonic flux command values ​​separated by order, since the differential operation can be performed analytically, no delay is generated. For example, if φ * dqh =sin(nω e T), then the second term of Equation (1) can be calculated as Equation (6), where T is time.

[0064] [Formula 6]

[0065] When controlling multiple orders, sum up the values ​​of each calculation formula (1) for each order to find v * dqh .

[0066] (Example 4) This embodiment is characterized in that the equation (1) used by the FF voltage calculation unit 9 is switched according to the operating conditions. This embodiment can be used as the FF voltage calculation unit 9 of any of the above-mentioned embodiments.

[0067] Compare the orders of the first, second and third terms on the right side of equation (1), as Figure 4 As shown, the influence of the second term's differential increases with increasing rotational speed, while the influence of the first term becomes almost nonexistent above a certain speed. In this embodiment, the FF voltage is calculated using equation (7) at a rotational speed where the first term is less than one-tenth the sum of the second and third terms. This allows the calculation workload in high-speed regions to be reduced as needed while maintaining accuracy across the entire speed range.

[0068] [Formula 7]

[0069] In addition, since each term of formula (1) includes the higher harmonic flux command value φ * dqh , so by comparing φ * dqhThe coefficient of , can grasp the approximate order. Specifically, based on the general L d , L q <<L dq , L qd In the case of d or R / L q Decision. The second item is φ * dqh The differential of φ * dqh According to the characteristics of torque pulsation, the electrical angular velocity ω e Therefore, the sum of the coefficients of the second and third terms is 10ω e About the order of magnitude.

[0070] According to the above simple coefficient research, according to R / L and 10ω e The ratio of the switching speed is used to determine the approximate switching speed. In addition, it is obvious that the switching speed depends on the current value. This is because L becomes smaller when magnetic saturation occurs and R / L becomes larger. Therefore, it is also possible to have a structure in which the switching of formula (1) and formula (7) is determined not only by the rotation speed but also by the size of the torque command value and the current value. In addition, since R / L d and R / L q In motors with salient polarity, the magnitude is different, so it can also be set according to the d-axis voltage v * dh and q-axis voltage v * qh The configuration of equations (1) and (7) can be switched according to the different rotation speed and current value for each step. In addition, it is also possible to combine with embodiment 3 to determine which one of equations (7) and (1) to use for each order.

[0071] The main features of Example 4 can also be summarized as follows.

[0072] Processor (FF voltage calculation unit 9, Figure 1 、 3 ) When the condition that the first term of formula (1) is less than 1 / 10 of the sum of the second and third terms is satisfied, the first term of formula (1) is regarded as 0 and the FF voltage command value v is calculated. * dqh In other words, when this condition is met, the processor (FF voltage calculation unit 9) calculates the FF voltage command value v according to formula (7). * dqh .

[0073] By not calculating the first term of equation (1), computing resources can be saved.

[0074] Specifically, the processor (FF voltage calculation unit 9, Figure 1 、 Figure 3 ) uses at least one of the motor's rotational speed, torque command value, current command value, and electrical angular velocity (electrical angular frequency) to determine whether the above conditions are met. For example, the range of parameters used in the motor's rotational speed, torque command value, current command value, and electrical angular velocity (electrical angular frequency) that meet the above conditions is pre-calculated (or pre-stored). If all the parameters used are within the range, the processor (FF voltage calculation unit 9) regards the first item of formula (1) as 0 and calculates the FF voltage command value v * dqh .

[0075] Whether the above conditions are satisfied can be easily determined by using at least one of the rotational speed, torque command value, current command value, and electrical angular velocity (electrical angular frequency) of the motor.

[0076] Furthermore, the present invention is not limited to the above-described embodiments and includes various variations. For example, the above-described embodiments are described in detail to facilitate understanding of the present invention and are not necessarily limited to embodiments having all the described configurations. Furthermore, a portion of the configuration of one embodiment may be replaced with a configuration of another embodiment, and a configuration of one embodiment may be added to a configuration of another embodiment. Furthermore, a portion of the configuration of each embodiment may be added, deleted, or replaced with another configuration.

[0077] Furthermore, part or all of the above-mentioned configurations and functions may be realized by hardware, for example, by designing an integrated circuit.

[0078] The present invention may be embodied in the following manners.

[0079] (A1). A motor control device that drives a motor through an inverter, the motor control device comprising: a higher harmonic flux command value calculation unit that calculates a higher harmonic flux command value based on a torque command value or a current command value and the electrical angle of the motor; an FF voltage calculation unit that calculates an FF voltage command value based on a rotational speed and the higher harmonic flux command value, taking into account a voltage drop caused by resistance; and a voltage command calculation unit that calculates a voltage command value, wherein the FF voltage command value is superimposed on the voltage command value.

[0080] (A2) In the motor control device described in (A1), the voltage command calculation unit calculates the voltage command value based on the current command value and the measured current value.

[0081] (A3) In the motor control device described in (A1), the voltage command calculation unit calculates the voltage command value based on a magnetic flux command value obtained by converting the current command value and the measured current value into magnetic flux and a measured magnetic flux value.

[0082] (A4) In the motor control device described in (A3), the voltage command calculation unit calculates the voltage command value based on a second magnetic flux command value obtained by superimposing the harmonic magnetic flux command value on the magnetic flux command value and the measured magnetic flux value.

[0083] (A5) In the motor control device described in (A1), the FF voltage calculation unit calculates the FF voltage command value using equation (1).

[0084] (A6) In the motor control device described in (A5), the FF voltage calculation unit calculates the FF voltage command value using equation (7) under the condition that the effective value of the first term of equation (1) is less than 1 / 10 of the effective values ​​of the second and third terms.

[0085] (A7) In the motor control device described in (A6), the condition uses at least one of a rotational speed, a torque, a current value, and an electrical angular frequency.

[0086] According to (A1) to (A7), it is possible to suppress an increase in necessary variables and the number of calculation steps, and to suppress torque ripple with high accuracy for a wide range of torque commands and rotation speeds. Explanation of symbols

[0087] 1…Motor control device, 2…dq-axis current command values, 3…Voltage command calculation unit, 4…Inverter, 5…Motor, 6…Electric angle detection unit, 7…Electric angular velocity calculation unit, 8…Higher harmonic flux command value calculation unit, 9…FF voltage calculation unit, 20…Torque command value, 21…Current command value calculation unit, 100…Converter.

Claims

1. A motor control device that drives a motor through an inverter, wherein: With processor, The processor calculates a higher harmonic flux command value based on a torque command value or a current command value and an electrical angle of the motor. An FF voltage command value is calculated based on the electrical angular velocity of the motor and the higher harmonic magnetic flux command value, wherein the FF voltage command value represents a feedforward voltage command value including a component corresponding to a voltage drop caused by resistance of the motor. The FF voltage command value is superimposed on the voltage command value.

2. The motor control device according to claim 1, wherein: The processor calculates the voltage command value based on the current command value and a measured current value.

3. The motor control device according to claim 1, wherein: The processor calculates the voltage command value based on a first magnetic flux command value converted from the current command value and a measured magnetic flux value converted from a measured current value.

4. The motor control device according to claim 3, wherein: The processor calculates the voltage command value based on a second magnetic flux command value obtained by superimposing the harmonic magnetic flux command value on the first magnetic flux command value and the measured magnetic flux value.

5. The motor control device according to claim 1, wherein: For the resistance R and the inductance L of the motor d , q-axis inductance L q , the interference inductance L between the d-axis and the q-axis dq 、L qd 、The higher harmonic component K of the magnet flux on the d-axis edh , the higher harmonic component K of the magnet flux on the q axis eqh , d-axis higher harmonic flux command value φ * dh , q-axis higher harmonic flux command value φ * qh , electrical angular velocity ω e , The processor calculates the FF voltage command value v according to the following formula (1): * dqh , [Formula 1] 6. The motor control device according to claim 5, wherein: When the condition that the first term of the formula (1) is less than 1 / 10 of the sum of the second term and the third term is satisfied, the processor regards the first term of the formula (1) as 0 and calculates the FF voltage command value.

7. The motor control device according to claim 6, wherein: The processor determines whether the condition is satisfied using at least one of the rotation speed of the motor, the torque command value, the current command value, and the electrical angular velocity.

8. The motor control device according to claim 1, wherein: The processor calculates the FF voltage command value using a flux-based motor inverse model.

9. The motor control device according to claim 8, It is characterized by. The processor calculates the FF voltage command value using four tables of static inductance and two tables of induced voltage constants instead of a table of dynamic inductance.

10. The motor control device according to claim 5, wherein: The processor calculates a component corresponding to the voltage drop caused by the resistance of the motor using the first term of equation (1).

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