Motor control method and motor control device

Abstract

To secure estimation accuracy of a magnetic pole position without depending on change of a motor rotation number.SOLUTION: A motor control method includes: a rotation number parameter acquisition step of controlling power supplied to a motor on the basis of a predetermined torque command value Tfin* and an estimated magnetic pole position θ' of a motor 200, and acquiring rotation number parameters N', N* suggesting a rotation number N of the motor; and a magnetic position calculation step of calculating the magnetic pole position on the basis of power parameters iddet, iqdet suggesting the power of the motor. Especially, the magnetic position calculation step estimates change dN / dt of a rotation number N from the rotation number parameter, and corrects the magnetic pole position on the basis of the change in the rotation number.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a control method that determines command values ​​for an orthogonal two-axis coordinate system (d-axis / q-axis coordinate system) by referring to the magnetic pole position of the motor, and uses these command values ​​to control the motor's drive. In this control method, the magnetic pole position of the motor is estimated from the detected value of the current flowing through the motor.

[0003] More specifically, an AC signal for estimating the magnetic pole position is superimposed on the d-axis component (d-axis command value) of the above command value to drive the motor, and the magnetic pole position is estimated based on the q-axis component (q-axis current detection value) of the current detection value acquired in that state. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-323099 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] However, depending on the control state, the motor speed may change, and the amount of change in the current detection value may become larger than expected. In such scenarios, there is a problem in that the estimation error of the magnetic pole position obtained from the current detection value becomes large.

[0006] Therefore, the object of the present invention is to provide a motor control method and a motor control device that can ensure the accuracy of estimating the magnetic pole position regardless of changes in motor rotation speed. [Means for solving the problem]

[0007] According to one aspect of the present invention, a motor control method is provided for controlling the power supplied to a motor based on a predetermined torque command value and an estimated magnetic pole position of the motor. This motor control method includes a rotation speed parameter acquisition step of acquiring rotation speed parameters that indicate the rotation speed of the motor, and a magnetic pole position calculation step of calculating the magnetic pole position based on power parameters that indicate the power of the motor. In particular, in the magnetic pole position calculation step, the change in rotation speed is estimated from the rotation speed parameters, and the magnetic pole position is corrected based on the change in rotation speed. Furthermore, in the rotational speed parameter acquisition process, an estimated signal is generated to estimate the magnetic pole position, the estimated signal is superimposed on a power command value that defines the power to be supplied to the motor, a response power value corresponding to the power command value with the estimated signal superimposed is calculated based on the power parameter, and the rotational speed parameter is calculated based on the response power value. In addition, the power command value includes the dq axis voltage command value, the estimated signal includes the dq axis high frequency voltage, the response power value includes the dq axis response high frequency current, and the power parameter includes the dq axis current. Then, in the rotational speed parameter acquisition process, the dq axis response high frequency current is calculated by filtering the detected value of the dq axis current, an estimated phase error value determined as the phase difference between the dq axis coordinate system and a pre-set 2-axis control coordinate system is calculated based on the dq axis response high frequency current, the estimated phase error value is corrected by a predetermined error correction value to calculate a corrected phase error estimate, and the estimated electrical angular velocity value and rotational speed value are calculated as rotational speed parameters based on the corrected phase error estimate. Furthermore, in the magnetic pole position calculation step, based on the estimated electrical angular velocity, an estimated phase value of the motor indicating the magnetic pole position is calculated, the change in the estimated rotational speed is calculated as a change in rotational speed, and an error correction value is increased or decreased according to the change in the estimated rotational speed. In addition, a mode selection step is included in which either a rotational speed control mode or a torque control mode is selected according to a predetermined control mode signal. The rotational speed control mode is a control mode in which a first torque command value determined from the rotational speed command value, which is the rotational speed that the motor should output, is set as the torque command value, and a power command value is calculated based on the first torque command value and the estimated rotational speed. The torque control mode is a control mode in which a second torque command value, which is determined as the torque that the motor should output, is set as the torque command value, and a power command value is calculated based on the second torque command value and the estimated rotational speed. When the rotational speed control mode is selected, the rotational speed command value is calculated as the rotational speed parameter in the rotational speed parameter acquisition step, and when the torque control mode is selected, the rotational speed estimate value is calculated as the rotational speed parameter. [Effects of the Invention]

[0008] According to the present invention, the accuracy of estimating the magnetic pole position can be ensured regardless of changes in motor rotation speed. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a block diagram showing the configuration of a motor control device according to one embodiment of the present invention. [Figure 2] Figure 2 is a block diagram showing the configuration of the rotation state estimation unit. [Figure 3] Figure 3 is a graph illustrating an example of how to determine the phase error correction value according to the rotational speed change rate and the q-axis current. [Figure 4] Figure 4 is a graph illustrating an example of how to determine the phase error correction value according to the voltage amplitude ratio. [Figure 5] Figure 5 is a flowchart showing the flow of estimation for motor rotation speed and magnetic pole position. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described below with reference to the drawings.

[0011] Figure 1 is a block diagram showing the configuration of the motor control device 100. As shown in Figure 1, the motor control device 100 is assumed to be a device that, instead of measuring the magnetic pole position (rotor position) and rotational speed (hereinafter referred to as "motor rotational speed N") of the motor 200 with sensors such as resolvers and encoders, calculates these based on an estimation algorithm described later, and uses the calculated estimated value to operate the inverter 18 and control the power supplied to the motor 200. In other words, the motor control system of this embodiment, consisting of the motor control device 100, inverter 18, and motor 200, can be configured as a position sensorless system. In particular, the motor 200 to be controlled is assumed to be an on-board motor for driving or a power generation motor. Furthermore, the motor 200 is, for example, a three-phase AC IPM (Interior Permanent Magnet) motor, with a q-axis inductance L q and d-axis inductance L d It is configured as a sali-polarity motor, where each element exhibits a different value.

[0012] The motor control device 100 comprises a rotation speed control unit 8, a torque command value selection unit 9, a current command generation unit 11, a first voltage command generation unit 12, a second voltage command generation unit 13, a final voltage command generation unit 14, a control mode signal generation unit 15, a coordinate transformation unit 16, a PWM conversion unit 17, a rotation state estimation unit 19, and a coordinate transformation unit 23. The motor control device 100 is composed of a computer (controller) equipped with a program to realize the functions of each unit. The hardware constituting the computer may consist of one or more units.

[0013] The rotational speed control unit 8 receives the rotational speed command value N from the higher-level control unit. * And based on the rotational speed estimate N' input from the rotational state estimation unit 19, the first torque command value T rev * Calculate and output the result.

[0014] Here, the rotational speed command value N *When used as a generator that regenerates and generates electricity, for example, by driving the motor 200 with a predetermined drive source (such as an engine), it is determined as the rotational speed of the motor 200 (hereinafter, also referred to as "motor rotational speed N") determined from the desired required generated power (engine torque × engine rotational speed). That is, the rotational speed command value N * is the target value of the rotational speed that the motor 200 should output, determined by the upper control device. Also, the estimated rotational speed value N' is an estimated value of the motor rotational speed N calculated according to the control state of the motor 200. The estimated rotational speed value N' is calculated (estimated) by the rotational state estimation unit 19 according to an estimation algorithm (high-frequency voltage application method) described later. Furthermore, the first torque command value T rev * is the target value of the output torque of the motor 200 to be aimed at in order to achieve the above rotational speed command value N * is the target value of the output torque of the motor 200 to be aimed at in order to achieve the above rotational speed command value N.

[0015] More specifically, the rotational speed control unit 8, for example, executes PI (Proportional-Integral) control based on the deviation between the rotational speed command value N * and the estimated rotational speed value N' to calculate the first torque command value T rev * is calculated.

[0016] The torque command value selection unit 9 is based on the control mode signal M sw1 input from the upper control device, the second torque command value T drv * input from the upper control device, and the above-mentioned first torque command value T rev * to calculate and output the final torque command value T fin * is calculated and output.

[0017] Here, the control mode signal M sw1 is a signal including command information of the upper control device regarding which of the torque control mode and the rotational speed control mode should be selected as the control mode. Also, the second torque command value T drv *This is, for example, the target value of the output torque of the motor 200 when the motor 200 is used as a driving source for a vehicle, according to the required driving force (such as the amount of operation on the accelerator pedal).

[0018] More specifically, the torque command value selection unit 9 receives the control mode signal M sw1 When it is determined that the torque control mode is being commanded to be executed by referring to the second torque command value T drv * The final torque command value T fin * The calculation is performed as follows. Meanwhile, the torque command value selection unit 9 receives the control mode signal M sw1 When it is determined that the rotational speed control mode is being commanded to be executed by referring to the above, the first torque command value T rev * The final torque command value T fin * Output as follows.

[0019] The current command generation unit 11 generates a DC voltage V dc , final torque command value T fin * , and based on the rotational speed estimate N′, the d-axis current command value i d * and q-axis current command value i q * Generate (calculate) and output it.

[0020] Here, the DC voltage V dc This is the output voltage of the battery 21 that supplies power to drive the motor 200. DC voltage V dc This is detected by the voltage sensor 22. Note that the DC voltage V dc This can be obtained as an estimated value from a battery controller (not shown) or the like, instead of the value detected by the voltage sensor 22.

[0021] d-axis current command value i d * The d-axis current i of motor 200 d This is the command value for the q-axis current command value i. q * The q-axis current i of motor 200 isq is the command value for. In the following, for simplicity of notation, the d-axis current i d and the q-axis current i q are included to form the dq-axis current i d , i q is also referred to as, and the d-axis current command value i d * and the q-axis current command value i q * are included to form the dq-axis current command value i d * , i q * is also referred to as.

[0022] The first voltage command generation unit 12 is based on the final torque command value T fin * , the DC voltage V dc , the estimated rotational speed N′, the dq-axis current command value i d * , i q * , and the detected values of the dq-axis current i<000006९>, i q to generate (calculate) and output the first d-axis voltage command value V d1 * and the first q-axis voltage command value V q1 * (hereinafter also referred to as "the first voltage command value V d1 * , V q1 * ").

[0023] The first voltage command value V d1 * , V q1 * is a voltage command value for controlling the motor 200 by so-called current vector control. That is, the first voltage command generation unit 12, for example, according to the following formula (1), calculates the deviation between the dq-axis current i d , i q s and the dq-axis current command value i d * , i , i q * (i d - i d * , i q - iq * Based on the PI control according to ( ) and the decoupling of the dq axes, the first voltage command value V d1 * , V q1 * is calculated.

[0024] [Number]

[0025] Note that "s" in Equation (1) is a differential operator. Also, "K p1 " is a proportional gain, and "K i1 " is an integral gain. Furthermore, "V d-dcpl * " is the d-axis interference voltage, and "V q-dcpl * ]>" is the q-axis interference voltage. In this embodiment, the first voltage command generation unit 12 associates the final torque command value T fin * , the DC voltage V dc , and the estimated rotational speed N' with the d-axis interference voltage V d-dcpl * and the q-axis interference voltage V q-dcpl * * [, and has an interference voltage table (not shown). Therefore, the first voltage command generation unit 12 refers to this interference voltage table to calculate the d-axis interference voltage V * dc , the DC voltage V dc , and the estimated rotational speed N' corresponding to the torque command value T d-dcpl * and the q-axis interference voltage V q-dcpl * * [. The interference voltage table is preset by experiments or simulations, etc.

[0026] Note that the dq-axis currents i d1 * , V q1 * used by the first voltage command generation unit 12 for the calculation of the first voltage command value V d , i qThis is the detected value of the current flowing through the motor 200, and is obtained from the coordinate transformation unit 23. The coordinate transformation unit 23 performs a coordinate transformation, for example, using the phase estimated value θ′ output by the rotation state estimation unit 19, to obtain the current i of each phase of the motor 200 detected by the current sensor 24. u ,i v ,i w From the dq axis current i d ,i q The following calculation is performed. Specifically, the coordinate transformation unit 23 calculates the dq axis current i according to equation (2) below. d ,i q Perform the calculation.

[0027]

number

[0028] Furthermore, in this embodiment, the current sensor 24 detects the U-phase current i of the motor 200. u and V-phase current i v Upon detecting this, the coordinate transformation unit 23 determines the W-phase current i w This is calculated by following the formula (3) below.

[0029]

number

[0030] In the following, the dq-axis current i is calculated based on equations (2) and (3) above. d ,i q The value of the dq axis current i d ,i q The detected value is considered to be the value, and when it is specifically indicated that it is a detected value, it is referred to as "dq axis current detected value i ddet ,i qdet "d-axis current detection value i" ddet ", or "q-axis current detection value i qdet It is written as "".

[0031] The second voltage command generation unit 13 generates the final torque command value T fin * DC voltage V dc , rotational speed estimate N′, and dq axis current id ,i q Based on this, the 2nd d-axis voltage command value V d2 * and the 2q-axis voltage command value V q2 * This generates (calculates) the second d-axis voltage command value V. d2 * and the 2q-axis voltage command value V q2 * The second voltage command value V d2 * ,V q2 * It is also called "..."

[0032] Second voltage command value V d2 * ,V q2 * This is a voltage command value for controlling the motor 200 by so-called voltage phase control. That is, the second voltage command generation unit 13 generates a voltage norm V a The command value for the voltage norm is V. a * And the command value for voltage phase α is the voltage phase command value α. * The second voltage command value V is calculated using the following: d2 * ,V q2 * Perform the calculation.

[0033] Specifically, the second voltage command generation unit 13 generates a DC voltage V according to, for example, the following equation (4): dc And the modulation rate command value MF is the command value for the modulation rate. * Based on this, the voltage norm command value V a * Perform the calculation.

[0034]

number

[0035] Furthermore, the second voltage command generation unit 13 generates the final torque command value T fin * DC voltage V dcBased on the estimated rotational speed N′, the voltage phase target value α ff * The following is calculated: Voltage phase target value α ff * This is the target value of the voltage phase α due to feedforward control. In this embodiment, the second voltage command generation unit 13 generates the final torque command value T fin * DC voltage V dc , and the rotational speed estimate N′, and the voltage phase target value α ff * It has a voltage phase target value table (not shown) that associates these values. Therefore, the second voltage command generation unit 13 refers to this voltage phase target value table to determine the final torque command value T fin * DC voltage V dc , and the voltage phase target value α corresponding to the rotational speed estimate N′ ff * The calculation is performed. The voltage phase target value table is predetermined by experimentation or simulation.

[0036] Furthermore, the second voltage command generation unit 13 detects the dq axis current i ddet ,i qdet Based on the rotational speed estimate N′, the torque estimate T is calculated as an estimated value of the output torque. est The calculation is performed. In this embodiment, the second voltage command generation unit 13 calculates the dq axis current i d ,i q And the rotational speed estimate N′ and the torque estimate T est It has a torque estimation table (not shown) that associates and . Therefore, the second voltage command generation unit 13 refers to this torque estimation table and determines the dq axis current detection value i ddet ,i qdet and the torque estimate T corresponding to the rotational speed estimate N′ est The calculation is performed. The torque estimation table is pre-set by experimentation or simulation, etc.

[0037] Furthermore, the second voltage command generation unit 13 generates the final torque command value T fin * and torque estimate T estBased on this, the voltage phase correction value α fb * The following is calculated: Voltage phase correction value α fb * The voltage phase target value α ff * This is a correction value for the torque command value T, and is calculated by feedback control. For example, the second voltage command generation unit 13 calculates the torque command value T according to the following equation (5). * and torque estimate T est The deviation from (T fin * -T est ) is controlled by PI control, which provides a voltage phase correction value α fb * Perform the calculation.

[0038]

number

[0039] In equation (5), "K p2 " is a proportional gain, and "K i2 This represents the integral gain.

[0040] Then, the second voltage command generation unit 13 calculates the voltage phase target value α as described above. ff * Voltage phase correction value α fb * By adding this, the voltage phase command value α * Perform the calculation.

[0041] Furthermore, the second voltage command generation unit 13 generates a voltage norm command value V as shown in equation (6) below. a * and voltage phase command value α * Based on the vector transformation, the second voltage command value V d2 * ,V q2 * Perform the calculation.

[0042]

number

[0043] The final voltage command generation unit 14 receives the control mode signal M from the control mode signal generation unit 15. sw2 Based on this, the first voltage command value V d1 * ,V q1 * and the second voltage command value V d2 * ,V q2 * Select one of the following, and the final voltage command value is the final voltage command value V d * ,V q * It outputs as follows: That is, the final voltage command generation unit 14 outputs the control mode signal M sw2 Accordingly, the control mode is set to the first voltage command value V d1 * ,V q1 * A current vector control mode using and a second voltage command value V d2 * ,V q2 * It selectively switches between a voltage phase control mode using and another mode.

[0044] In this embodiment, the final voltage command generation unit 14 generates the control mode signal M sw2 The first voltage command value V selected based on this is d1 * ,V q1 * Or the second voltage command value V d2 * ,V q2 * Then, high-frequency voltage V dh * ,V qh * The output is obtained by superimposing (adding) the two values. Note that, as will be described later, the rotation state estimation unit 19 calculates the high-frequency voltage V dh * ,V qh * The final voltage command value V is obtained by superimposing the two values. d * ,V q * Response power value (response high-frequency current i)dh ,i qh This is to calculate the rotational speed estimate N′ and the phase estimate θ′ from ).

[0045] Note that the high-frequency voltage V dh * ,V qh * This is expressed by the following equation (7).

[0046]

number

[0047] Here, in equation (7), "V h " is a high-frequency voltage V dh * ,V qh * The amplitude is "ω h " is a frequency. Also, "K h (0≦K h ≤1) is a predetermined phase difference (phase error θ described later) with respect to the dq axis coordinate system. γ High-frequency voltage V in a two-axis control coordinate system (γδ axis coordinate system) with ) dh * ,V qh * These are coefficients that determine the trajectory. In particular, K h If = 0, then the high-frequency voltage V dh * ,V qh * The trajectory is a straight line along the γ axis, 0 <K h When <1, the locus is an ellipse centered at the origin of the γδ axis (the origin of the dq axis). Furthermore, K h When = 1, the locus is a perfect circle centered at the origin of the γδ axis. Also, as can be seen from equation (7), "K h " is the d-axis high-frequency voltage V dh * q-axis high-frequency voltage V with respect to amplitude qh * This defines the ratio of the amplitudes. Therefore, for the sake of explanation below, this ratio of amplitudes will be referred to as the "voltage amplitude ratio K". h It is also called "". Note that the amplitude V h, frequency ω h , and voltage amplitude ratio K h This is pre-set by compatibility.

[0048] The control mode signal generation unit 15 generates a DC voltage V dc and final voltage command value V d * ,V q * Based on this, control mode signal M sw2 Generates.

[0049] Specifically, the control mode signal generation unit 15 generates a DC voltage V according to the following equation (8). dc and final voltage command value V d * ,V q * Based on this, the modulation index (MF) is calculated.

[0050]

number

[0051] Furthermore, the control mode signal generation unit 15 sets the calculated modulation rate MF to a predetermined threshold (modulation rate threshold TH). MF ) is compared with the modulation rate threshold TH. Then, the control mode signal generation unit 15 generates a control mode signal such that, for example, the modulation rate MF is compared with the modulation rate threshold TH. MF When it is less than the first voltage command value V d1 * ,V q1 * Control mode signal M that selects (current vector control mode) sw It generates and outputs the following. Meanwhile, the control mode signal generation unit 15 generates the following signal, for example, when the modulation rate MF is the modulation rate threshold TH. MF When the above is true, the second voltage command value V d2 * ,V q2 * Control mode signal M that selects (voltage phase control mode) sw2 Generate and output the following.

[0052] The modulation rate threshold TH used to determine the switching from current vector control mode to voltage phase control mode is also used. MF The modulation rate threshold TH is used to determine the switching from voltage phase control mode to current vector control mode. MF And can be set to different values. In this case, hysteresis can be introduced into the switching between the current vector control mode and the voltage phase control mode, thereby suppressing frequent switching between each mode (so-called chattering).

[0053] The coordinate transformation unit 16 performs a coordinate transformation using, for example, the phase estimated value θ′ output by the rotation state estimation unit 19 to obtain the final voltage command value V d * ,V q * From there, the three-phase voltage command value V u * ,V v * ,V w * The coordinate transformation unit 16 calculates the three-phase voltage command value V according to the following equation (9). u * ,V v * ,V w * Perform the calculation.

[0054]

number

[0055] The PWM conversion unit 17 outputs a DC voltage V dc and three-phase voltage command value V u * ,V v * ,V w * Based on this, a PWM (Pulse Width Modulation) signal is generated to drive the power elements of the inverter 18. Specifically, the PWM conversion unit 17 generates a three-phase voltage command value V u * ,V v * ,V w *Power element drive signal D corresponding to this signal uu * ,D ul * ,D vu * ,D vl * ,D wu * ,D wl * This is generated and input to the inverter 18. The PWM conversion unit 17 can perform so-called dead time compensation processing and voltage utilization rate improvement processing when generating the PWM signal.

[0056] The inverter 18 switches the power elements according to the PWM signal, thereby controlling the DC voltage V of the battery 21. dc This is a pseudo-AC voltage V u ,V v ,V w This is converted and input to each of the UVW phases of motor 200. As a result, motor 200 receives the final torque command value T. fin * It is controlled to output torque accordingly.

[0057] The rotation state estimation unit 19 detects the dq axis current i ddet ,i qdet , final voltage command value V d * ,V q * , rotational speed command value N * , and control mode signal M sw1 Based on this, the rotational state of the motor 200 is estimated. Here, the rotational state of the motor 200 refers to parameters that identify the operating state of the rotor of the motor 200, such as the phase θ that defines the rotor position, and the mechanical angular velocity, electrical angular velocity ω, and motor rotational speed N that define the rotational speed of the rotor. In this embodiment, the rotational state estimation unit 19 calculates and outputs the estimated phase value θ′, which is an estimated value of the phase θ, and the above-mentioned estimated rotational speed N′ as the rotational state of the motor 200. The details of the rotational state estimation unit 19 will be described below.

[0058] Figure 2 is a block diagram showing the configuration of the rotation state estimation unit 19. In this embodiment, the rotation state estimation unit 19 measures the q-axis inductance L of the motor 200. q and d-axis inductance L d The phase estimate θ′ and rotational speed estimate N′ are calculated using the high-frequency voltage application method (mirror phase estimation method), which is a magnetic position estimation algorithm that utilizes the difference in these factors.

[0059] Specifically, the rotation state estimation unit 19 includes a phase error estimation unit 31, a phase estimated value calculation unit 32, a rotation speed estimated value calculation unit 33, a phase correction value calculation unit 34, and a phase error correction unit 35.

[0060] The phase error estimation unit 31 detects the dq axis current i ddet ,i qdet , and the final voltage command value V d * ,V q * Using as input, the estimated phase error θ γ The value ' is calculated and output. Here, the estimated phase error value θ is calculated. γ ′ represents the phase error θ between the dq axis coordinate system and a predetermined two-axis control coordinate system (γδ axis coordinate system). γ This is an estimated value.

[0061] First, as a premise, the first voltage command value V is as described above. d1 * ,V q1 * Or the second voltage command value V d2 * ,V q2 * A high-frequency voltage V is superimposed on it. dh * ,V qh * As shown in equation (7), it traces an elliptical orbit with major and minor axes in directions that coincide with the γ axis and δ axis, respectively. Then, the high-frequency voltage V dh * ,V qh * The response power value for the response is the response high-frequency current i. dh ,i qhSimilarly, it draws an elliptical orbit on the γδ-axis coordinate system. Here, the response high-frequency current i dh , i qh The major axis of makes a deviation corresponding to a predetermined phase difference (hereinafter referred to as "major axis phase θ γe ") with respect to the d-axis. On the other hand, when both the phase error θ γ between the above-described dq-axis coordinate system and γδ-axis coordinate system and the major axis phase θ γe are very small, they can be regarded as coinciding with each other. Therefore, if the major axis phase θ γe is obtained, this can be used as an estimated value of the phase error θ γ (hereinafter also referred to as "phase error estimated value θ γ ′").

[0062] Therefore, the phase error estimation unit 31 executes the following arithmetic logic for determining the major axis phase θ ddet , i qdet from the dq-axis current detection values i d * , V q * and the final voltage command values V γe to calculate the phase error estimated value θ γ ′.

[0063] Specifically, the phase error estimation unit 31 extracts the response high-frequency current i ddet , i qdet from the dq-axis current detection values i dh , i qh by filtering processing using, for example, a band-pass filter or the like. The band-pass filter is configured to remove or reduce the DC component from the dq-axis current detection values i dh * , V qh * according to the frequency ω[[ID=�3]] h of the high-frequency voltage V ddet , i qdet . Next, the phase error estimation unit 31 calculates the positive-phase component (in-phase component) [c dh , i qh of the response high-frequency current i p , s p and the reverse-phase component (mirror-image component) [cn , s n and perform an operation on them.

[0064]

Number

[0065] Then, the rotation state estimation unit 19 further uses a low-pass filter or the like to perform filtering processing for removing or reducing harmonic components such as the frequency 2ω p , s p and the quadrature component [c n , s n . The filtered quadrature component [c h etc. p , s p and the quadrature component [c n , s n are symmetric (mirror image relationship) with respect to the major axis phase θ re (phase error estimated value θ γ ′) in the γδ-axis coordinate system. Therefore, the phase error estimation unit 31 calculates the phase error estimated value θ p , s p and the quadrature component [c n , s n according to the following equation (12). γ ′.

[0066]

Number

[0067] Based on the corrected phase error estimated value θ γc ′ calculated by the phase error correction unit 35, the phase estimated value calculation unit 32 calculates and outputs the estimated value of the electrical angular velocity ω′, which is the estimated value of the electrical angular velocity, by PI control of the following equation (13).

[0068]

Number

[0069] Furthermore, the phase estimation unit 32 calculates and outputs the phase estimation value θ′ by integrating the electrical angular velocity estimation value ω′ according to the following equation (14).

[0070]

number

[0071] The rotational speed estimation unit 33 calculates and outputs the rotational speed estimation value N' [rad] by converting the unit of the electrical angular velocity estimation value ω' [rad / sec] calculated by the phase estimation unit 32.

[0072] The phase correction value calculation unit 34 receives the control mode signal M sw1 q-axis current detection value i qdet , rotational speed command value N * The estimated rotational speed N' (especially the previous value of the estimated rotational speed N') is used as input to estimate the phase error θ γ The phase error correction value Δθ is a correction value used to correct ′. γ Calculate and output the result.

[0073] More specifically, the phase correction value calculation unit 34 calculates the control mode signal M sw1 When the torque control mode is indicated, the rotational speed change rate dN / dt is calculated by applying a high-pass filter or the like to the rotational speed estimate N' fed back from the phase estimate calculation unit 32. On the other hand, the phase correction value calculation unit 34 receives the control mode signal M sw1 When this indicates a rotation speed control mode, the rotation speed command value N * The rotational speed change rate dN / dt is calculated by applying a high-pass filter or similar process to the data.

[0074] Furthermore, the phase correction value calculation unit 34 calculates a phase error correction value Δθ according to the sign of the calculated rotational speed change rate dN / dt. γ The sign of is determined. More specifically, the phase correction value calculation unit 34 determines the phase error correction value Δθ when the sign of the rotational speed change rate dN / dt is positive (when the motor rotational speed N is increasing). γ The sign of is set to positive (phase error estimate θ) γ(Augmentation correction is performed for '). In addition, the phase correction value calculation unit 34 calculates the phase error correction value Δθ when the sign of the rotational speed change rate dN / dt is negative (when the motor rotational speed N decreases). γ The sign of is set to negative (phase error estimate θ) γ (Apply a reduction correction to ').

[0075] Furthermore, the phase correction value calculation unit 34 calculates the magnitude of the rotational speed change rate dN / dt and the q-axis current detection value i qdet Based on the absolute value of Δθ, the phase error correction value is calculated. γ The magnitude of the phase correction value is determined. In particular, the phase correction value calculation unit 34 determines a provisional phase error correction value Δθ according to the magnitude of the rotational speed change rate dN / dt. γpre The provisional phase error correction value Δθ is determined. γpre , q-axis current detection value i qdet Correction value adjustment amount Δθ according to the magnitude of the absolute value γadj By adding this, the final phase error correction value Δθ is obtained. γ We seek.

[0076] Figure 3 shows the phase error correction value Δθ. γ This graph illustrates one example of how to determine the values. In particular, Figure 3(a) shows the magnitude of the rotational speed change rate dN / dt and the provisional phase error correction value Δθ. γpre An example of the relationship between and is shown. Also, Figure 3(b) shows the q-axis current detection value i qdet The absolute value of and the correction value adjustment amount Δθ γadj This shows the relationship between and .

[0077] First, as shown in Figure 3(a), the phase correction value calculation unit 34 calculates a predetermined basic phase error correction value Δθ. γb The provisional phase error correction value Δθ is corrected to take a larger value in proportion to the increase in the magnitude of the rotational speed change rate dN / dt, based on the reference value. γpre The following is determined. Furthermore, the basic phase error correction value Δθ γb This can be set to an appropriate variable value or a fixed value (including 0) depending on the characteristics of the control system.

[0078] On the other hand, as shown in Figure 3(b), the phase correction value calculation unit 34 adjusts the correction value by Δθ. γadjis set to take a larger value as the absolute value of the q-axis current detection value i qdet becomes larger.

[0079] The above-mentioned provisional phase error correction value Δθ γpre and the correction value adjustment amount Δθ γadj The phase error correction value Δθ γ obtained as the sum of is determined as a value in which a positive correlation among the change in the motor rotation speed N, the magnitude of the q-axis current i q and the phase error estimated value θ γ ′ is appropriately taken into account.

[0080] In this embodiment, the high-frequency voltage injection method is adopted as the magnetic position estimation algorithm. And in the said estimation algorithm, the high-frequency voltage V d * , V q * superimposed on dh * , V qh * Regarding dh * the d-axis high-frequency voltage V qh * the ratio of the amplitude of the q-axis high-frequency voltage V h to the amplitude of (that is, the voltage amplitude ratio K γ ) tends to increase as the phase error correction value Δθ γadj becomes smaller. Therefore, considering this tendency, instead of the absolute value of the q-axis current detection value i qdet , a configuration may be adopted in which the correction value adjustment amount Δθ h is determined according to the above-mentioned voltage amplitude ratio K

[0081] More specifically, as shown in FIG. 4, the phase error correction value Δθ γ is set to take a larger value as the voltage amplitude ratio K h becomes smaller. Thereby, even in a scene showing the above tendency, the accuracy of the phase error estimated value θ γ ′ can be ensured.

[0082] Also, the correction value adjustment amount Δθ γadjThe q-axis current detection value i qdet Instead of a configuration determined according to the absolute value of i, the q-axis current command value i q * The estimated q-axis current i calculated from qest A configuration determined according to the absolute value of may also be adopted. In this case, the estimated q-axis current i qest For example, the q-axis current command value i q * For this, the q-axis current command value i q * The calculation can be performed by methods such as processing with a filter defined considering the response characteristics from the actual q-axis current.

[0083] Returning to Figure 2, the phase error correction unit 35 calculates the estimated phase error θ. γ ′ and phase error correction value Δθ γ Based on this, the corrected phase error estimate θ γc The ' is calculated. The phase error correction unit 35 is composed of, for example, an adder. Therefore, in this embodiment, the phase error correction unit 35 calculates the estimated phase error θ. γ ′ with phase error correction value Δθ γ By adding this, the corrected phase error estimate θ γc We seek '.

[0084] Then, the corrected phase error estimate θ calculated by the phase error correction unit 35 is obtained. γc ′ is input to the phase estimation calculation unit 32. As a result, the phase estimation value θ′ and the electrical angular velocity estimation value ω′ calculated by the phase estimation calculation unit 32 are used for rotational speed change rate dN / dt and q-axis current i q Phase error correction value Δθ adjusted accordingly γ The value is corrected based on this. Similarly, the rotational speed estimate N′ calculated from this electrical angular velocity estimate ω′ in the rotational speed estimation unit 33 is also corrected.

[0085] Next, the calculation logic for estimating the magnetic pole position of the motor 200 (determining the phase estimate value θ′) in the motor control method of this embodiment will be explained with reference to a flowchart.

[0086] Figure 5 is a flowchart showing an example of the logic for estimating the magnetic pole position of the motor 200. The following processes are repeatedly executed by the motor control device 100 at predetermined calculation cycles.

[0087] As shown in the figure, first in step S10, the final voltage command value V d * ,V q * d-axis current detection value i ddet q-axis current detection value i qdet , q-axis current command value i q * , rotational speed command value N * , rotational speed estimate N′, and control mode signal M sw2 Obtain it.

[0088] In step S20, the phase error estimate value θ is calculated according to the calculation logic of the phase error estimation unit 31 described above. γ Perform the calculation '.

[0089] In step S30, the rotational speed change rate dN / dt is calculated according to the calculation logic of the phase correction value calculation unit 34 described above. In particular, the control mode signal M sw2 If the current control mode is determined to be torque control mode by referring to the following, the rotational speed change rate dN / dt is calculated from the rotational speed estimate N'. On the other hand, if the current control mode is determined to be rotational speed control mode, the rotational speed command value N * The rotational speed change rate dN / dt is calculated from this.

[0090] In step S40, the q-axis current i q The absolute value of (q-axis current detection value i) qdet or q-axis current estimate i q_est Calculate the absolute value of (...).

[0091] In step S50, the phase error correction value Δθ is calculated according to the calculation logic of the phase correction value calculation unit 34 described above. γ The following are calculated: In particular, the rotational speed change rate dN / dt and the q-axis current i qBased on the absolute value, the final phase error correction value Δθ is calculated using the calculation logic described in Figure 3. γ We seek.

[0092] In step S60, the corrected phase error estimate θ is calculated according to the calculation logic of the phase error correction unit 35 described above. γc The ' is calculated. In particular, the phase error estimate θ obtained in step S20. γ ′ is the phase error correction value Δθ obtained in step S50. γ By adding this, the estimated corrected phase error θ γc We seek '.

[0093] In step S70, the phase error correction value Δθ is calculated according to the calculation logic of the phase estimation calculation unit 32 described above. γ The phase estimate θ′ and the electrical angular velocity estimate ω′ are calculated from this. Furthermore, according to the calculation logic of the rotational speed estimation unit 33 described above, the rotational speed estimate N′ is calculated from the electrical angular velocity estimate ω′.

[0094] The effects and advantages of the motor control method of this embodiment, as described above, will be summarized below.

[0095] According to this embodiment, a predetermined torque command value (final torque command value T) fin * A motor control method is provided that controls the power supplied to the motor 200 based on the estimated magnetic pole position (phase estimated value θ′) of the motor 200.

[0096] This motor control method uses rotational speed parameters (estimated rotational speed N′, rotational speed command value N) that indicate the rotational speed of motor 200 (motor rotational speed N). * The process involves acquiring rotational speed parameters (dq axis current detection value i) to obtain an estimated electrical angular velocity (ω′), and power parameters (dq axis current detection value i) that indicate the power of the motor 200. ddet ,i qdet The system includes a magnetic pole position calculation step (phase error estimation unit 31, phase estimated value calculation unit 32, phase correction value calculation unit 34, phase error correction unit 35) which calculates the magnetic pole position based on the above.

[0097] Then, in the magnetic pole position calculation process (phase correction value calculation unit 34), the change in motor rotation speed N is estimated from the rotation speed parameter, and the magnetic pole position is corrected based on the change in motor rotation speed N.

[0098] This allows for the determination of an appropriately adjusted estimated magnetic pole position, taking into account changes in motor rotation speed N. Therefore, even in scenarios where motor rotation speed N changes, the accuracy of the estimated magnetic position of the motor 200 can be maintained, suppressing the occurrence of issues such as step-out in torque control. As a result, the torque range of motor control that can be performed without using a magnetic position sensor can be further expanded.

[0099] In particular, during the rotational speed parameter acquisition process, an estimation signal is generated to estimate the magnetic pole position, the estimation signal is superimposed on a power command value that defines the power to be supplied to the motor 200, a response power value corresponding to the power command value with the estimation signal superimposed is calculated based on the power parameters, and the rotational speed parameters are calculated based on the response power value.

[0100] This enables a calculation logic that determines the rotational speed parameter used for correcting the magnetic pole position as a value that appropriately reflects the actual change in the rotational speed of the motor 200.

[0101] More specifically, in the motor control method of this embodiment, the above voltage command value is the dq axis voltage command value (first voltage command value V d1 * ,V q1 * Or the second voltage command value V d2 * ,V q2 * ) includes, and the estimated signal is the dq axis high frequency voltage (high frequency voltage V dh * ,V qh * ) includes, and the response power value is the dq axis response high-frequency current (response high-frequency current i dh ,i qh ) includes the power parameter i of the dq axis. d ,i q Includes.

[0102] Then, in the rotation speed parameter acquisition process, the dq axis current i d ,i q Detected value (dq axis current detection value i) ddet ,i qdet By applying a filter to the response high-frequency current i dh ,i qh The response high-frequency current i is calculated and dh ,i qh Based on this, the estimated phase error θ is determined as the phase difference between the dq axis coordinate system and the pre-set two-axis control coordinate system (γδ coordinate system). γ ' is calculated, and the phase error estimate θ is obtained. γ ′ is a predetermined error correction value (phase error correction value Δθ) γ The corrected phase error estimate θ is obtained by correcting it using ) γc ' is calculated, and the corrected phase error estimate θ is obtained. γc Based on ', the estimated electrical angular velocity ω' and the estimated rotational speed N' are calculated as rotational speed parameters.

[0103] Then, in the magnetic pole position calculation process, based on the estimated electrical angular velocity ω′, the estimated phase value θ′ of the motor 200 that suggests the magnetic pole position is calculated, the change in the estimated rotational speed N′ is calculated as a change in the motor rotational speed N, and the phase error correction value Δθ is calculated. γ This value is increased or decreased in accordance with the change in the estimated rotational speed N′ (see Figure 3(a)).

[0104] This enables a more specific control logic to appropriately correct the calculated value of the magnetic pole position by taking into account changes in the motor rotation speed N, assuming the adoption of an estimation algorithm (high-frequency voltage application method) that estimates the magnetic pole position of the motor 200 by superimposing a high-frequency voltage signal onto the voltage command value.

[0105] In particular, in this case, the magnetic pole position calculation process involves the change in the estimated rotational speed N′ and the q-axis current i. q Based on this, the phase error correction value Δθ γ Adjust.

[0106] This allows for changes in motor rotation speed N, as well as q-axis current i.q and phase error correction value Δθ γ This allows for the determination of more appropriate estimates of magnetic pole positions by taking into account the correlations.

[0107] Furthermore, in the magnetic pole position calculation process, the q-axis current i q The larger the absolute value of Δθ, the greater the phase error correction value. γ Make it larger (see Figure 3(b)).

[0108] This results in the q-axis current i q The larger the absolute value of Δθ, the greater the phase error correction value. γ This allows us to determine more appropriate estimates of magnetic pole positions that take into account the tendency for the coefficient to increase.

[0109] Furthermore, in the magnetic pole position calculation process, the phase error correction value Δθ is calculated according to the direction of change of the estimated rotational speed N′ (the positive or negative sign of the rotational speed change rate dN / dt). γ Switch between positive and negative signs.

[0110] This results in a phase error correction value Δθ depending on the direction of increase or decrease of the motor rotation speed N. γ This allows for the determination of more appropriate estimates of magnetic pole positions that take into account the tendency for them to take on different signs.

[0111] Furthermore, in the magnetic pole position calculation process, the larger the change in the estimated rotational speed N′ (the magnitude of the rotational speed change rate dN / dt), the greater the phase error correction value Δθ. γ Make it bigger.

[0112] As a result, the phase error correction value Δθ increases as the increase or decrease in motor rotation speed N increases. γ This allows for the determination of more appropriate estimates of magnetic pole positions that take these tendencies into account.

[0113] Furthermore, in the magnetic pole position calculation process, the change in the estimated rotational speed N′ and the d-axis high-frequency voltage V are considered. dh * Q-axis high-frequency voltage V qh * Amplitude ratio (voltage amplitude ratio K) h Based on ) and the phase error correction value Δθγ A configuration that adjusts the voltage amplitude ratio K can also be adopted. In particular, in this case, the voltage amplitude ratio K h The smaller the value, the greater the phase error correction value Δθ. γ Make it larger (see Figure 4).

[0114] This results in a voltage amplitude ratio K h The phase error correction value Δθ increases in proportion to the decrease. γ This allows for the determination of more appropriate estimates of magnetic pole positions that take these tendencies into account.

[0115] Furthermore, the motor control method of this embodiment uses a predetermined control mode signal M sw1 The system further includes a mode selection step (torque command value selection unit 9) that selects either a rotation speed control mode or a torque control mode accordingly.

[0116] In particular, the rotational speed control mode uses a rotational speed command value N as the rotational speed that the motor 200 should output. * The first torque command value T is determined from this. rev * The final torque command value T fin * The first torque command value T is set as follows: rev * This control mode calculates the power command value based on the rotational speed estimate N'. The torque control mode uses a second torque command value T, which is determined as the torque that the motor 200 should output. drv * The final torque command value T fin * The second torque command value T is set as follows: drv * This control mode calculates the power command value based on the estimated rotational speed N′.

[0117] Furthermore, if the rotation speed control mode is selected, in the rotation speed parameter acquisition process described above, the rotation speed command value N * The above rotational speed parameter is used for calculation. On the other hand, if torque control mode is selected, the estimated rotational speed N' is used as the above rotational speed parameter for calculation.

[0118] This enables a control system that can selectively execute both a torque control mode, which assumes that the motor 200 is primarily used for traction as a driving source for the vehicle, and a rotational speed control mode, which assumes that the motor 200 is primarily used for regenerative operation as an on-board generator. In this system, a specific control logic is realized to appropriately estimate the magnetic pole position while taking into account changes in the motor rotational speed N.

[0119] In particular, in rotational speed control mode, the rotational speed command value N corresponds to the target value of the motor rotational speed N determined by the higher-level control device, etc. * Refer to the change in the phase error correction value Δθ γ The following calculation is performed: Therefore, the phase error correction value Δθ, which is the result of this calculation, is calculated. γ Chattering (vibration) is suppressed. More specifically, the rotational speed estimate N′, which is determined according to the state variables in the current control system, is expected to frequently switch in the direction of change (increase or decrease) in a short period of time depending on the control state. Therefore, if the change in the rotational speed estimate N′ is directly referenced, the phase error correction value Δθ, which is the calculation result, will be affected by the frequent switching of the direction of change. γ It is also expected to vibrate. In contrast, the rotational speed command value N' has less switching in the direction of change compared to the rotational speed estimate value N'. * By referring to the change, the calculated phase error correction value Δθ γ This suppresses vibrations and reduces chattering (frequent switching between increase / decrease corrections) in the correction calculation for the final magnetic pole position (phase estimate θ′).

[0120] Furthermore, this embodiment provides a motor control device 100 suitable for executing the above motor control method.

[0121] This motor control device 100 provides rotational speed parameters (estimated rotational speed N', rotational speed command value N) that indicate the rotational speed (motor rotational speed N) of the motor 200. * A rotational speed parameter acquisition unit obtains an estimated electrical angular velocity (ω′), and a power parameter (dq axis current detection value i) that indicates the power of the motor 200. ddet ,i qdetIt includes a magnetic pole position calculation unit (phase error estimation unit 31, phase estimated value calculation unit 32, phase correction value calculation unit 34, phase error correction unit 35) that calculates the magnetic pole position based on (etc.).

[0122] The magnetic pole position calculation unit (phase correction value calculation unit 34) then estimates the change in motor rotation speed N from the rotation speed parameter and corrects the magnetic pole position based on the change in motor rotation speed N.

[0123] Although embodiments of the present invention have been described above, the configurations described in the above embodiments and each of the modifications represent only a part of the application examples of the present invention and are not intended to limit the technical scope of the present invention.

[0124] For example, in the above embodiment, an example was described in which the phase estimate θ′ is corrected by referring to the change in motor rotation speed N, based on a high-frequency voltage application method (mirror phase estimation method) that utilizes the inductance difference between the dq axes. However, the embodiment is not limited to this, and an example in which the phase estimate θ′ is corrected based on the change in motor rotation speed N, based on other estimation algorithms, may also be adopted. For example, it is also possible to adopt a configuration in which an observer of the magnetic flux or induced voltage of the motor 200 is defined, and an estimation algorithm is used to obtain the rotation speed estimate N′ and the phase estimate θ′ from various control values ​​using the observer, and the phase estimate θ′ is corrected by referring to the change in motor rotation speed N. [Explanation of Symbols]

[0125] 8. Speed ​​control unit 9 Torque command value selection unit 11 Current command generation section 12 First Voltage Command Generation Unit 13. Second Voltage Command Generation Unit 14. Final Voltage Command Generation Unit 18 Inverters 19. Rotation state estimation unit 31 Phase error estimation section 32 Phase Estimation Calculation Unit 33. Rotational Speed ​​Estimation Calculation Unit 34 Phase Correction Value Calculation Unit 35 Phase error correction section 100 Motor control device 200 motor

Claims

1. A motor control method for controlling the power supplied to a motor based on a predetermined torque command value and an estimated magnetic pole position of the motor, A rotation speed parameter acquisition step is to acquire rotation speed parameters that indicate the rotation speed of the motor, The process includes a magnetic pole position calculation step which calculates the magnetic pole position based on power parameters that indicate the power of the motor, In the aforementioned magnetic pole position calculation step, The change in rotational speed is estimated from the rotational speed parameter, The magnetic pole position is corrected based on the change in rotational speed. In the aforementioned rotational speed parameter acquisition process, An estimated signal is generated for estimating the magnetic pole position, The estimated signal is superimposed on the power command value that defines the power to be supplied to the motor. Based on the power parameters, a response power value corresponding to the power command value with the estimated signal superimposed is calculated. Based on the response power value, the rotational speed parameter is calculated, The aforementioned power command value includes the dq axis voltage command value. The estimated signal includes a dq-axis high-frequency voltage, The aforementioned response power value includes the dq-axis response high-frequency current. The aforementioned power parameters include the dq axis current, In the aforementioned rotational speed parameter acquisition process, The dq-axis response high-frequency current is calculated by applying a filter to the detected value of the dq-axis current. Based on the dq-axis response high-frequency current, an estimated phase error value is calculated, which is determined as the phase difference between the dq-axis coordinate system and a pre-set two-axis control coordinate system. The estimated phase error is corrected by a predetermined error correction value to calculate a corrected estimated phase error. Based on the aforementioned corrected phase error estimate, the estimated electrical angular velocity and rotational speed, which are rotational speed parameters, are calculated. In the aforementioned magnetic pole position calculation step, Based on the estimated electrical angular velocity, the estimated phase value of the motor that suggests the magnetic pole position is calculated. The change in the rotational speed is calculated as the change in the estimated rotational speed, The error correction value is increased or decreased in accordance with the change in the estimated rotational speed. The process further includes a mode selection step of selecting either a rotational speed control mode or a torque control mode in accordance with a predetermined control mode signal. The rotational speed control mode is a control mode in which a first torque command value determined from the rotational speed command value which is the rotational speed that the motor should output is set as the torque command value, and the power command value is calculated based on the first torque command value and the rotational speed estimate value. The torque control mode is a control mode in which a second torque command value, which is determined as the torque that the motor should output, is set as the torque command value, and the power command value is calculated based on the second torque command value and the rotational speed estimate value. When the aforementioned rotation speed control mode is selected, In the rotation speed parameter acquisition step, the rotation speed command value is calculated as the rotation speed parameter, When the torque control mode is selected, the rotational speed estimate is calculated using the rotational speed parameter. Motor control method.

2. A motor control method according to claim 1, In the aforementioned magnetic pole position calculation step, Based on the change in the estimated rotational speed and the q-axis current, the error correction value is adjusted. Motor control method.

3. A motor control method according to claim 2, In the aforementioned magnetic pole position calculation step, The larger the absolute value of the q-axis current, the larger the error correction value. Motor control method.

4. A motor control method according to claim 1, In the aforementioned magnetic pole position calculation step, Depending on the direction of change of the estimated rotational speed, the sign of the error correction value is switched. Motor control method.

5. A motor control method according to claim 1, In the aforementioned magnetic pole position calculation step, The larger the change in the estimated rotational speed, the larger the error correction value. Motor control method.

6. A motor control method according to claim 1, In the aforementioned magnetic pole position calculation step, The error correction value is adjusted based on the change in the estimated rotational speed and the amplitude ratio of the q-axis high-frequency voltage to the d-axis high-frequency voltage. The smaller the amplitude ratio, the larger the error correction value. Motor control method.

7. A motor control device that controls the power supplied to the motor based on a predetermined torque command value and the estimated magnetic pole position of the motor, A rotation speed parameter acquisition unit that acquires rotation speed parameters that indicate the rotation speed of the motor, The system includes a magnetic pole position calculation unit that calculates the magnetic pole position based on power parameters that indicate the power of the motor, The aforementioned magnetic pole position calculation unit is: The change in rotational speed is estimated from the rotational speed parameter, The magnetic pole position is corrected based on the change in rotational speed. The rotation speed parameter acquisition unit is, An estimated signal is generated for estimating the magnetic pole position, The estimated signal is superimposed on the power command value that defines the power to be supplied to the motor. Based on the power parameters, a response power value corresponding to the power command value with the estimated signal superimposed is calculated. Based on the response power value, the rotational speed parameter is calculated, The aforementioned power command value includes the dq axis voltage command value. The estimated signal includes a dq-axis high-frequency voltage, The aforementioned response power value includes the dq-axis response high-frequency current. The aforementioned power parameters include the dq axis current, The rotation speed parameter acquisition unit is, The dq-axis response high-frequency current is calculated by applying a filter to the detected value of the dq-axis current. Based on the dq-axis response high-frequency current, an estimated phase error value is calculated, which is determined as the phase difference between the dq-axis coordinate system and a pre-set two-axis control coordinate system. The estimated phase error is corrected by a predetermined error correction value to calculate a corrected estimated phase error. Based on the aforementioned corrected phase error estimate, the estimated electrical angular velocity and rotational speed, which are rotational speed parameters, are calculated. The aforementioned magnetic pole position calculation unit is: Based on the estimated electrical angular velocity, the estimated phase value of the motor that suggests the magnetic pole position is calculated. The change in the rotational speed is calculated as the change in the estimated rotational speed, The error correction value is increased or decreased in accordance with the change in the estimated rotational speed. The system further includes a mode selection unit that selects either a rotational speed control mode or a torque control mode in accordance with a predetermined control mode signal. The rotational speed control mode is a control mode in which a first torque command value determined from the rotational speed command value which is the rotational speed that the motor should output is set as the torque command value, and the power command value is calculated based on the first torque command value and the rotational speed estimate value. The torque control mode is a control mode in which a second torque command value, which is determined as the torque that the motor should output, is set as the torque command value, and the power command value is calculated based on the second torque command value and the rotational speed estimate value. When the aforementioned rotation speed control mode is selected, The rotation speed parameter acquisition unit calculates the rotation speed command value as the rotation speed parameter, When the torque control mode is selected, the rotational speed estimate is calculated using the rotational speed parameter. Motor control device.

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