Motor control method and motor control device

Abstract

This motor control method includes: calculating a basic command current for achieving a desired efficiency in accordance with an operation point of a motor; calculating a warming-up current obtained by correcting the basic command current so as to generate a required loss for warming up a battery; calculating a corrected warming-up current for setting a salient pole ratio of the motor within a predetermined range while generating a certain amount of loss used for warming up; and setting one of the warming-up current and the corrected warming-up current as a current command value with reference to the operation parameters of the motor.

Description

Motor control method and motor control device

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

[0002] JP2020-96425A discloses a motor drive method in which the magnet position of the motor is estimated from the relationship between the voltage applied to drive the motor and the current flowing through the motor.

[0003] However, in the control of JP2020-96425A, when a command current is set to raise the temperature (warm up) of the battery, the current operating point of the motor may deviate from the maximum efficiency current operating point, changing the salient pole ratio of the motor and making it impossible to ensure the accuracy of the magnet position estimation.

[0004] Therefore, an object of the present invention is to provide a motor control method and a motor control device that can ensure the accuracy of magnet position estimation while also ensuring the loss (heat generation amount) used for warming up the battery.

[0005] According to one aspect of the present invention, there is provided a motor control method that estimates a response current to an input of a current command value superimposed with an estimation current, estimates a magnetic pole position of a motor based on the estimated response current, and controls power supplied from a battery to the motor based on the estimated magnetic pole position and the current command value.

[0006] In this motor control method, a basic command current that achieves a desired efficiency in accordance with the operating point of the motor is calculated, a warm-up current is calculated by correcting the basic command current so as to generate a required loss for warming up the battery, a corrected warm-up current is calculated that generates a certain amount of loss used for warm-up while keeping the salient pole ratio of the motor within a predetermined range, and either the warm-up current or the corrected warm-up current is set as the current command value with reference to the motor's operating parameters.

[0007] FIG. 1 is a block diagram showing the configuration of a motor control device according to an embodiment of the present invention. FIG. 2 is a block diagram showing details of a phase / rotation speed estimator. FIG. 3 is a block diagram showing details of a current command generator. FIG. 4 is a block diagram showing details of a warm-up current command generator. FIG. 5 is a diagram showing an example of the relationship between a basic command current, a first magnetizing current, a demagnetizing current, and a second magnetizing current. FIG. 6 is a flowchart showing a first example of processing in the current command generator. FIG. 7 is a flowchart showing a second example of processing in the current command generator. FIG. 8 is a timing chart showing an example of the results when a control algorithm according to this embodiment is applied.

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] FIG. 1 is a block diagram showing the configuration of a motor control device 100. As shown in FIG. 1, the motor control device 100 is assumed to be a device that, instead of measuring the magnetic pole position (rotor position) and rotation speed N of a motor 200 using sensors such as a resolver or encoder, calculates the magnetic pole position (rotor position) and rotation speed N based on an estimation algorithm described below, and uses the calculated estimated value to operate an inverter 18 and control the power supplied to the motor 200. In other words, a motor control system including the motor control device 100, inverter 18, and motor 200 of this embodiment can be configured as a position sensorless system. In particular, the motor 200 to be controlled is assumed to be, for example, a driving motor mounted on an electric vehicle such as an EV or HEV. The motor 200 is, for example, a three-phase AC IPM (Interior Permanent Magnet) motor, and has a q-axis inductance L ｑ and d-axis inductance L ｄ are configured as salient pole motors in which the values ​​of

[0010] Motor control device 100 includes a current command generator 11, a first voltage command generator 12, a second voltage command generator 13, a final voltage command generator 14, a control mode signal generator 15, a coordinate converter 16, a PWM converter 17, a phase / rotation speed estimator 19, and a coordinate converter 23. Motor control device 100 is configured by a computer (controller) equipped with a program to realize the functions of each unit. The hardware constituting the computer may be one or more units.

[0011] The current command generating unit 11 receives a warm-up request signal, a torque command value T ＊ , and the rotation speed estimated value N′, the final d-axis current command value i ｄ ＊＊ and the final q-axis current command value i ｑ ＊＊ The final d-axis current command value i ｄ ＊＊ and the final q-axis current command value i ｑ ＊＊ are the d-axis current i of the motor 200, respectively. ｄ and q-axis current i ｑ This is the final command value for specifying the

[0012] The warm-up request signal is generated by a predetermined upper control device (such as a vehicle controller) and indicates whether or not there is a request for warming up the battery 21 (for example, warming up the battery 21 before charging it with an external charging facility). ＊ is a target value of the torque (output torque) of motor 200 specified by a higher-level control device. In particular, when motor 200 is used as a driving source for a vehicle, it is set to an appropriate value depending on the required driving force (such as the amount of operation of the accelerator pedal). Furthermore, estimated rotation speed value N' is an estimate of the rotation speed N of motor 200 calculated depending on the control state of motor 200. Estimated rotation speed value N' is calculated (estimated) by phase / rotation speed estimator 19.

[0013] The processing of the current command generating unit 11 will be described in detail later.

[0014] The first voltage command generator 12 generates a torque command value T ＊, rotation speed estimate N′, dq axis current command value i ｄ ＊ , i ｑ ＊ , and the dq axis current i ｄ , i ｑ Based on the detected value of ｄ１ ＊ , V ｑ１ ＊ Generate (calculate) and output.

[0015] First dq-axis voltage command value V ｄ１ ＊ , V ｑ１ ＊ are voltage command values ​​for controlling the motor 200 by so-called current vector control. That is, the first voltage command generator 12 calculates the d-axis current i ｄ , i ｑ and the dq axis current command value i ｄ ＊ , i ｑ ＊ Deviation of (i ｄ -i ｄ ＊ , i ｑ -i ｑ ＊ ) and the decoupling of the d and q axes, the first d and q axis voltage command value V ｄ１ ＊ , V ｑ１ ＊ Calculate the following.

[0016]

[0017] In addition, "s" in Equation 1 is a differential operator. ｐ１ " is the proportional gain, and "K ｉ１ " is the integral gain. 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 generator 12 generates the torque command value T ＊ , DC voltage V ｄｃ , and the estimated rotation speed N′ and the d-axis interference voltage V ｄ－ｄｃｐｌ ＊ and q-axis interference voltage Vｑ－ｄｃｐｌ ＊ Therefore, the first voltage command generating unit 12 can obtain the torque command value T ＊ , DC voltage V ｄｃ , and the d-axis interference voltage V corresponding to the rotation speed estimate N′ ｄ－ｄｃｐｌ ＊ and q-axis interference voltage V ｑ－ｄｃｐｌ ＊ The interference voltage table is set in advance through experiments, simulations, or the like.

[0018] The first voltage command generator 12 generates the first dq-axis voltage command value V ｄ１ ＊ , V ｑ１ ＊ The dq axis current i used in the calculation ｄ , i ｑ is a detected value of the current flowing through the motor 200, and is acquired from the coordinate conversion unit 23. The coordinate conversion unit 23 converts the current i of each phase of the motor 200 detected by the current sensor 24 by coordinate conversion using the phase estimation value θ′ output by the phase / rotation speed estimation unit 19, for example. ｕ , i ｖ , i ｗ From dq axis current i ｄ , i ｑ Calculate the following.

[0019] In the following, the dq axis current i calculated in this way will be ｄ , i ｑ The value of dq axis current i ｄ , i ｑ When it is specifically stated that it is a detected value, it is called "dq axis current detection value i ｄｄｅｔ , i ｑｄｅｔ ", "d-axis current detection value i ｄｄｅｔ " or "q-axis current detection value i ｑｄｅｔ ". The dq axis current detection value i ｄｄｅｔ , i ｑｄｅｔ When a high frequency voltage command is added in the final voltage command generating unit 14, the voltage command can be used after being subjected to a predetermined filter that cuts the frequency of the high frequency voltage command.

[0020] The second voltage command generator 13 generates a torque command value T ＊ , DC voltage V ｄｃ , the estimated rotation speed N′, and the dq-axis current i ｄ , i ｑ Based on this, the second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ Generate (calculate)

[0021] Second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ is a voltage command value for controlling the motor 200 by so-called voltage phase control. That is, the second voltage command generating unit 13 generates a voltage norm V ａ The voltage norm command value V ａ ＊ and a voltage phase command value α ＊ and are used to calculate the second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ The DC voltage V ｄｃ is the output voltage of the battery 21 for supplying driving power to the motor 200. ｄｃ is detected by the voltage sensor 22. ｄｃ Instead of the detected value by the voltage sensor 22, it may be acquired as an estimated value obtained by a battery controller (not shown) or the like.

[0022] Specifically, the second voltage command generator 13 calculates the DC voltage V ｄｃ and a modulation rate command value MF ＊ Based on this, the voltage norm command value V ａ ＊ Calculate the following.

[0023]

[0024] Furthermore, the second voltage command generator 13 generates a torque command value T ＊ , DC voltage V ｄｃ, and the rotation speed estimated value N′, the voltage phase target value α ｆｆ ＊ Calculate the voltage phase target value α ｆｆ ＊ is a target value of the voltage phase α by feedforward control. In this embodiment, the second voltage command generator 13 generates the torque command value T ＊ , DC voltage V ｄｃ , and the rotation speed estimate N′ and the voltage phase target value α ｆｆ ＊ Therefore, the second voltage command generating unit 13 can obtain the torque command value T ＊ , DC voltage V ｄｃ , and the voltage phase target value α corresponding to the rotation speed estimate value N′ ｆｆ ＊ The voltage phase target value table is set in advance through experiments, simulations, or the like.

[0025] The second voltage command generator 13 also generates the dq-axis current detection value i ｄｄｅｔ , i ｑｄｅｔ and the estimated rotation speed N′, the torque estimated value T ｅｓｔ In this embodiment, the second voltage command generator 13 calculates the dq-axis current i ｄ , i ｑ and the rotation speed estimate N′ and the torque estimate T ｅｓｔ Therefore, the second voltage command generator 13 refers to this torque estimation value table to determine the d-axis current detection value i ｄｄｅｔ , i ｑｄｅｔ and the torque estimate T corresponding to the rotation speed estimate N′ ｅｓｔ The torque estimation value table is set in advance through experiments, simulations, or the like.

[0026] Furthermore, the second voltage command generator 13 generates a torque command value T ＊ and the torque estimate T ｅｓｔ Based on this, the voltage phase correction value α ｆｂ ＊Calculate the voltage phase correction value α ｆｂ ＊ is the voltage phase target value α ｆｆ ＊ For example, the second voltage command generator 13 calculates the torque command value T ＊ and the torque estimate T ｅｓｔ Deviation from (T ＊ -T ｅｓｔ ) is used to calculate the voltage phase correction value α ｆｂ ＊ Calculate the following.

[0027]

[0028] "K" in Equation 3 ｐ２ " is the proportional gain, and "K ｉ２ " is the integral gain.

[0029] The second voltage command generator 13 then calculates the voltage phase target value α ｆｆ ＊ Voltage phase correction value α ｆｂ ＊ By adding ＊ Calculate the following.

[0030] Furthermore, the second voltage command generator 13 calculates the voltage norm command value V ａ ＊ and voltage phase command value α ＊ The second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ Calculate the following.

[0031]

[0032] The final voltage command generator 14 calculates the first dq-axis voltage command value V based on the control mode signal Msw input from the control mode signal generator 15. ｄ１ ＊ , V ｑ１ ＊ and the second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊and selects one of the two, and the final voltage command value V ｄ ＊ , V ｑ ＊ That is, the final voltage command generator 14 outputs the control mode as the first dq-axis voltage command value V ｄ１ ＊ , V ｑ１ ＊ and a current vector control mode using a second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ and a voltage phase control mode using

[0033] In this embodiment, the final voltage command generator 14 generates the first dq-axis voltage command value V selected based on the control mode signal Msw. ｄ１ ＊ , V ｑ１ ＊ or the second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ the final voltage command value V ｄ ＊ , V ｑ ＊ In addition, when the estimated values ​​of the magnetic pole position and the rotation speed N (the phase estimated value θ′ and the rotation speed estimated value N′) obtained by processing by the first estimator 191 of the phase / rotation speed estimator 19 described later are used, the selected first dq-axis voltage command value V ｄ１ ＊ , V ｑ１ ＊ or the second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ The high frequency voltage V is determined by the following equation 5. ｄｈ ＊ , V ｑｈ ＊ The final voltage command value V obtained by superimposing (adding) ｄ ＊ , V ｑ ＊On the other hand, when the phase estimation value θ′ and the rotation speed estimation value N′ obtained by the processing by the second estimation unit 192 of the phase / rotation speed estimation unit 19 are used, the selected first dq-axis voltage command value V ｄ１ ＊ , V ｑ１ ＊ or the second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ is used as the final voltage command value V ｄ ＊ , V ｑ ＊ Output as

[0034]

[0035] "V" in Equation 5 ｈ " is the high frequency voltage V ｄｈ ＊ , V ｑｈ ＊ is the fundamental amplitude of "ω ｈ " is the frequency. The fundamental amplitude V ｈ , and frequency ω ｈ is preset by the fit.

[0036] The control mode signal generator 15 generates a DC voltage V ｄｃ and the final voltage command value V ｄ ＊ , V ｑ ＊ The control mode signal Msw is generated based on the above.

[0037] Specifically, the control mode signal generator 15 calculates the DC voltage V ｄｃ and the final voltage command value V ｄ ＊ , V ｑ ＊ The modulation factor MF is calculated based on the above.

[0038]

[0039] The control mode signal generator 15 also calculates the calculated modulation factor MF based on a predetermined threshold value (modulation factor threshold value TH ＭＦ ) and the control mode signal generator 15 compares the modulation factor MF with the modulation factor threshold value TH.ＭＦ When the first dq-axis voltage command value V ｄ１ ＊ , V ｑ１ ＊ (current vector control mode) ｓｗ On the other hand, the control mode signal generator 15 generates and outputs the modulation factor MF when the modulation factor MF is greater than or equal to the modulation factor threshold TH ＭＦ When the second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ The control mode signal Msw for selecting the voltage phase control mode is generated and output.

[0040] The modulation factor threshold TH used to determine whether to switch from the current vector control mode to the voltage phase control mode is ＭＦ and a modulation factor threshold value TH used to determine whether to switch from the voltage phase control mode to the current vector control mode. ＭＦ and may be set to different values. In this case, hysteresis can be imparted to the switching between the current vector control mode and the voltage phase control mode, thereby suppressing frequent switching between the modes (so-called chattering).

[0041] The coordinate transformation unit 16 performs coordinate transformation using the phase estimation value θ′ output by the phase / rotation speed estimation unit 19 to obtain the final voltage command value V ｄ ＊ , V ｑ ＊ From the above, the three-phase voltage command value V ｕ ＊ , V ｖ ＊ , V ｗ ＊ Specifically, the coordinate conversion unit 16 calculates the three-phase voltage command value V ｕ ＊ , V ｖ ＊ , V ｗ ＊ Calculate the following.

[0042]

[0043] The PWM conversion unit 17 converts the DC voltage V ｄｃ and the three-phase voltage command value Vｕ ＊ , V ｖ ＊ , V ｗ ＊ Specifically, the PWM conversion unit 17 generates a PWM (Pulse Width Modulation) signal for driving the power elements of the inverter 18 based on the three-phase voltage command value V ｕ ＊ , V ｖ ＊ , V ｗ ＊ The power element drive signal D corresponding to ｕｕ ＊ , D ｕｌ ＊ , D ｖｕ ＊ , D ｖｌ ＊ , D ｗｕ ＊ , D ｗｌ ＊ and inputs this to the inverter 18. When generating the PWM signal, the PWM conversion unit 17 can perform so-called dead time compensation processing and voltage utilization rate improvement processing.

[0044] The inverter 18 switches the power elements in accordance with the PWM signal to generate a DC voltage V ｄｃ is the pseudo AC voltage V ｕ , V ｖ , V ｗ and input to each of the UVW phases of the motor 200. As a result, the motor 200 receives the torque command value T ＊ The torque T is controlled to be output in accordance with the torque T.

[0045] The phase / rotation speed estimation unit 19 estimates the d-axis and q-axis current detection values ​​i ｄｄｅｔ , i ｑｄｅｔ and the final voltage command value V ｄ ＊ , V ｑ ＊ The phase estimated value θ′ is an estimate of the phase θ that defines the rotor position of the motor 200.

[0046] 2 is a block diagram showing details of the phase / rotation speed estimator 19. As shown in the figure, the phase / rotation speed estimator 19 has a first estimator 191, a second estimator 192, and a rotation state calculator 193.

[0047] The first estimation unit 191 estimates the high-frequency voltage V ｄｈ ＊ , V ｑｈ ＊ The final voltage command value V ｄ ＊ , V ｑ ＊ is applied to the motor 200, the response high frequency current i ｄｈ , i ｑｈ Based on this, the q-axis inductance L of the motor 200 ｑ and d-axis inductance L ｄ The first phase estimate θ １ ' is calculated.

[0048] First, as a premise, the first dq-axis voltage command value V ｄ１ ＊ , V ｑ１ ＊ or the second dq-axis voltage command value V ｄ２ ＊ , V ｑ２ ＊ The high frequency voltage V superimposed on ｄｈ ＊ , V ｑｈ ＊ The high frequency voltage V ｄｈ ＊ , V ｑｈ ＊ The response power value for the high frequency current i ｄｈ , i ｑｈ also draws an elliptical orbit on the γδ-axis coordinate system. Here, the response high-frequency current i ｄｈ , i ｑｈ The major axis of the d-axis has a predetermined phase difference (hereinafter referred to as the "major axis phase θ ｒｅ On the other hand, the phase error θ between the dq-axis coordinate system and the γδ-axis coordinate system described above occurs. γ and the major axis phase θ γｅWhen both are small, they can be considered to coincide with each other. γｅ is calculated as the phase error θ γ (hereinafter referred to as the "first phase error estimate θ γ１ ').

[0049] Therefore, the first estimation unit 191 estimates the dq-axis current detection value i ｄｄｅｔ , i ｑｄｅｔ From the major axis phase θ γｅ The first phase error estimate θ is calculated by executing the following calculation logic to determine γ１ ' is calculated.

[0050] Specifically, the first estimation unit 191 estimates the d-axis and q-axis current detection values ​​i ｄｄｅｔ , i ｑｄｅｔ From the response high frequency current i ｄｈ , i ｑｈ The bandpass filter extracts, for example, a high frequency voltage V ｄｈ ＊ , V ｑｈ ＊ The frequency ω ｈ In response to this, the dq axis current detection value i ｄｄｅｔ , i ｑｄｅｔ Next, the first estimator 191 calculates the response high-frequency current i ｄｈ , i ｑｈ The positive-phase component (in-phase component) of [c' ｐ , s′ ｐ ] and the reverse phase component (mirror phase component) [c ' ｎ , s′ ｎ ] and are calculated.

[0051]

[0052] The first estimator 191 then further uses a low-pass filter or the like to estimate the positive-sequence components [c' ｐ , s′ ｐ ] and the reverse phase component [c' ｎ , s′ ｎ ], the frequency 2ω ｈThe filtering process is performed to remove or reduce harmonic components such as the positive-phase component [c ｐ , s ｐ ] and the reverse phase component [c ｎ , s ｎ ] is the major axis phase θ ｒｅ (first phase error estimate θ γ１ Therefore, the phase / rotation speed estimation unit 19 calculates the positive sequence component [c ｐ , s ｐ ] and the reverse phase component [c ｎ , s ｎ ] to obtain the first phase error estimate θ γ１ ' is calculated.

[0053]

[0054] The first estimator 191 also calculates the first phase error estimate θ γ１ Based on this, a first electrical angular velocity estimate ω, which is an estimate of the electrical angular velocity ω of the motor 200, is calculated by PI control of the following equation 11: １ ' is calculated.

[0055]

[0056] Furthermore, the first estimator 191 calculates the first electrical angular velocity estimate value ω according to the following equation 12: １ The first phase estimate θ １ ' is calculated.

[0057]

[0058] The first estimator 191 also calculates the first electrical angular velocity estimate ω １ The first rotation speed estimate N １ ' [rpm] is calculated.

[0059] Here, the first estimation unit 191 estimates the q-axis inductance L ｑ and d-axis inductance L ｄ Using the difference between the first phase estimate θ １ ' and the first rotation speed estimate N １ Therefore, the q-axis inductance Lｑ and d-axis inductance L ｄ The ratio of (in this embodiment, L ｑ / L ｄ ) is not equal to or greater than a certain value, it is not possible to ensure the accuracy of position estimation. On the other hand, when warming up the battery 21, a loss may be generated by shifting the current of the motor 200 from the current operating point at which the current is most efficient, and this loss (heat generation) may be utilized. In this case, depending on the operating point of the motor 200 (particularly when the motor 200 is operating in a low rotation range), shifting the current from the current operating point at which the current is most efficient toward the magnetization side (magnetization direction) may reduce the salient pole ratio r (more specifically, the salient pole ratio approaches 1), which may result in a problem in which the accuracy of the estimation calculation in the first estimator 191 that utilizes the inductance difference cannot be ensured.

[0060] In response to this, the inventors have arrived at the idea of ​​adjusting the current command value so as to ensure the accuracy of the estimation calculation in the first estimator 191 (so that the salient pole ratio r is equal to or greater than a certain value) when the operating point of the motor 200 is in a state where the current command value should be corrected to the magnetization side and when warming up the battery 21. A specific method for adjusting the current command value will be described later.

[0061] The second estimation unit 192 estimates the d-axis and q-axis current detection values ​​i ｄｄｅｔ , i ｑｄｅｔ and the final voltage command value V ｄ ＊ , V ｑ ＊ The following calculation algorithm is executed to obtain the second phase estimate θ ２ ' is calculated.

[0062] More specifically, the second estimator 192 calculates the second phase estimate θ by the following calculation algorithms (I) to (VII): ２ ' and the second rotation speed estimate N ２ ' is calculated.

[0063] (I) The voltage equation (Equation 13) expressed in the dq-axis coordinate system in the motor 200 is re-expressed in terms of the γδ axes having a phase difference of θγ from the dq-axis coordinate system (Equations 14 to 17).

[0064]

[0065] In addition, "R" in each formula is the winding resistance [Ω], "L ｄ " is the d-axis inductance [H], "L ｑ " represents the q-axis inductance [H], "s" represents the differential operator, "ω" represents the rotation speed (electrical angular velocity) [rad / s], and "Φ" represents the magnet magnetic flux [Wb]. γ , v δ ] represents the voltage on the γδ axes (γ-axis voltage and δ-axis voltage), and [i γ , i δ ] represents the current in the γδ axes (γ-axis current and δ-axis current), and [φ ｉγ , φ ｉδ ] is the stator reaction flux φ in the γδ axis ｉ (reaction flux generated by the stator current), and [φ ｍγ , φ ｍδ ] is the rotor magnetic flux φ in the γδ axis ｍ Furthermore, [L ｉ , L ｍ ] represent the positive and negative inductances of the stator, respectively.

[0066] (II) By transforming the circuit equation in the γδ axes expressed by the above equation 14, the rotor magnetic flux φ ｍ The state equation and output equation of minimum dimension are derived with the state variables as follows. That is, Equation 14 is converted into the rotor flux φ ｍ is converted into a state space representation in which is a state variable, and the following equation 18 is obtained: The first equation of equation 18 is the state equation, and the second equation is the output equation.

[0067]

[0068] (III) Based on the state equation and output equation of Equation 18, the rotor flux φ, which is a state variable, is calculated. ｍ (= [φ ｍγ , φ ｍδ ]) is defined by the following equation 19.

[0069] In the equation, "G" represents a 2x2 observer gain matrix, and "I" represents an identity matrix. The observer gain matrix G is determined in advance by experiment, simulation, or the like.

[0070] Therefore, using Equation 19, the rotor magnetic flux φ in the γδ axes is ｍ ([φ ｍγ , φ ｍδ ]) (hereinafter referred to as the rotor flux density estimated value (φ ｍγ , φ ｍδ ) is requested.

[0071] (IV) The obtained rotor flux density estimate (φ ｍγ , φ ｍδ ) is subjected to arctangent processing of the following equation 20 to obtain a second phase error estimate θ γ２ ' is calculated.

[0072]

[0073] (V) The obtained second phase error estimate θ γ２ ', a second electrical angular velocity estimate ω, which is an estimate of the electrical angular velocity ω of the motor 200, is obtained by PI control expressed by the following equation 21: ２ ' is calculated.

[0074]

[0075] (VI) Obtained second electrical angular velocity estimate value ω ２ ' is subjected to integration processing of Equation 22 to obtain the second phase estimate θ ２ ' is calculated.

[0076]

[0077] (VII) Second electrical angular velocity estimate ω ２ ' [rad / s] is converted into the second rotation speed estimate N ２ ' [rpm] is calculated.

[0078] Next, the rotation state calculation unit 193 calculates the output signal (θ １ ', N １ ') and the output signal (θ ２ ', N ２From the estimated phase value θ′ and the estimated rotation speed value N′, the final estimated phase value θ′ and the estimated rotation speed value N′ are calculated.

[0079] More specifically, the rotation state calculation unit 193 calculates the output signal (θ １ ', N １ ') and the output signal (θ ２ ', N ２ The final estimated phase value θ′ and estimated rotation speed value N′ are calculated by performing weighting calculations expressed by the following equations 23 and 24 on the estimated phase value θ′.

[0080] In addition, "w" in each formula １ " is the first weighting factor, and "w ２ " indicates the second weighting coefficient. In particular, the first weighting coefficient w １ and the second weighting factor w ２ Haha １ +w ２ = 1. Furthermore, the first weighting coefficient w １ and the second weighting factor w ２ is set to a variable value according to the rotation speed N of the motor 200. For example, when the rotation speed N is equal to or smaller than a predetermined first threshold value N Ａ If it is less than or equal to, the first weighting factor w １ and the second weighting factor w ２ are 1 and 0, respectively, and the rotation speed N is equal to or exceeds the first threshold value N Ａ greater than the second threshold N Ｂ In the following region, the first weighting factor w １ goes from 1 to 0, and the second weighting factor w ２ changes linearly from 0 to 1, and the rotation speed N is equal to or exceeds the second threshold value N Ｂ In the region exceeding １ and the second weighting factor w ２ can be set to 0 and 1, respectively. This allows the estimation results of the first estimator 191 and the second estimator 192 to be weighted appropriately in accordance with the magnitude of the rotation speed N, thereby making it possible to calculate the final phase estimate θ′ and rotation speed estimate N′.

[0081] Next, the details of the processing of the current command generating unit 11 will be described. As described above, the current command generating unit 11 generates the torque command value T ＊, and the rotation speed estimation value N′ calculated by the phase / rotation speed estimation unit 19 are input, and the final dq axis current command value i ｄ ＊＊ , i ｑ ＊＊ Calculate.

[0082] 3 is a block diagram showing details of the current command generator 11. As shown in the figure, the current command generator 11 has a base current command generator 101, a warm-up current command generator 102, and a final command current generator 103.

[0083] The basic current command generating unit 101 generates a torque command value T ＊ and the rotational speed estimated value N' are input, and a predetermined normal time dq axis current table is referenced to determine a basic command current i, which is a current command value during normal times (when warm-up of the battery 21 is not performed). ｄｎ ＊ , i ｑｎ ＊ The basic dq-axis current table calculates the dq-axis current i that maximizes efficiency according to the operating point (torque T, rotation speed N) of the motor 200. ｄ , i ｑ This is a table that defines the basic command current i ｄｎ ＊ , i ｑｎ ＊ is the torque command value T that defines the current operating point (T, N) of the motor 200. ＊ and the estimated rotation speed N', the current command value is determined as the current command value that maximizes the operating efficiency of the motor 200.

[0084] The warm-up current command generator 102 generates a torque command value T ＊ and the rotation speed estimated value N′ are input, and a warm-up dq-axis current command value i is calculated as a current command value used when warming up the battery 21. ｄｗ ＊ , i ｑｗ ＊ Calculate.

[0085] 4 is a block diagram showing details of the warm-up current command generator 102. As shown in the figure, the warm-up current command generator 102 is composed of a first magnetizing current generator 1021, a demagnetizing current generator 1022, a second magnetizing current command generator 1023, a salient pole ratio estimator 1024, and a warm-up current determiner 1025.

[0086] The first magnetizing current generator 1021 generates a torque command value T ＊ and the rotation speed estimated value N' are input, and the first magnetizing current i is calculated by referring to a predetermined first magnetizing dq axis current table. ｄ１ ＊ , i ｑ１ ＊ The first magnetization dq-axis current table calculates the basic command current i so as to ensure the required loss that is appropriately determined for warming up the battery 21 according to the torque T and the rotation speed N of the motor 200. ｄｎ ＊ , i ｑｎ ＊ The dq axis current i ｄ , i ｑ This is a table that determines the basic command current i so as to increase the main magnetic flux generated under the same torque T and rotation speed N. ｄｎ ＊ , i ｑｎ ＊ is corrected so that the absolute value of the q-axis component becomes larger.

[0087] That is, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ is the current command value (basic command current i ｄｎ ＊ , i ｑｎ ＊ ) is corrected in the direction of reducing the field weakening. ｄ１ ＊ , i ｑ１ ＊The basic command current i is calculated by multiplying the loss caused by the high frequency current (estimated current) superimposed for estimating the phase and rotation speed by referring to the first magnetization dq axis current table. ｄｎ ＊ , i ｑｎ ＊ Alternatively, the correction amount may be reduced.

[0088] The demagnetizing current generating unit 1022 generates a torque command value T ＊ and the rotation speed estimated value N' are input, and the demagnetizing current i is calculated by referring to a predetermined demagnetizing dq axis current table. ｄ２ ＊ , i ｑ２ ＊ The demagnetization dq axis current table is used to calculate the torque command value T ＊ While realizing this, the basic command current i ｄｎ ＊ , i ｑｎ ＊ The dq axis current i ｄ , i ｑ This is a table that determines the basic command current i ｄｎ ＊ , i ｑｎ ＊ The d-axis component is decreased (corrected in the negative direction) and the q-axis component is increased (corrected in the positive direction) relative to the demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ is the basic command current i ｄｎ ＊ , i ｑｎ ＊ is determined as a value corrected in the direction of increasing the field weakening. ｄ２ ＊ , i ｑ２ ＊ The basic command current i is calculated by multiplying the loss caused by the high frequency current (estimated current) superimposed for estimating the phase and rotation speed by referring to the demagnetization dq axis current table. ｄｎ ＊ , i ｑｎ ＊It may be set to a value close to .

[0089] The second magnetizing current command generator 1023 generates a torque command value T ＊ and the rotation speed estimated value N' are input, and the second magnetizing current i is calculated by referring to a predetermined second magnetizing dq axis current table. ｄ３ ＊ , i ｑ３ ＊ The second magnetization dq axis current table calculates the torque command value T ＊ While realizing this, the salient pole ratio r of the motor 200 is the minimum salient pole ratio r that can be driven without a sensor. ｍ The basic command current i ｄｎ ＊ , i ｑｎ ＊ The dq axis current i ｄ , i ｑ This is a table that determines the basic command current i ｄｎ ＊ , i ｑｎ ＊ The dq-axis current values ​​are defined by increasing the d-axis component (correcting in the positive direction) and decreasing the q-axis component (correcting in the negative direction) with respect to the dq-axis current.

[0090] The salient pole ratio estimation unit 1024 estimates the first magnetizing current i obtained by the first magnetizing current generation unit 1021. ｄ１ ＊ , i ｑ１ ＊ is input, and an estimated value of the salient pole ratio r (hereinafter referred to as "estimated salient pole ratio r'") is calculated by referring to a predetermined saliency ratio table. ｄ , i ｑ (The q-axis current i, which is particularly correlated with the torque T, ｑ Since there is a certain correlation between the first magnetizing current i and the salient pole ratio r, the correlation can be investigated in advance by experiment or simulation to obtain a desired salient pole ratio table. For example, the salient pole ratio table can be obtained by calculating the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ The q-axis component i ｑ１ ＊The table is defined as returning a higher estimated saliency ratio r' value as the torque T increases (the torque T increases).

[0091] FIG. 5 shows the basic command current i ｄｎ ＊ , i ｑｎ ＊ , first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ , demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ , and the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ As shown in the figure, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ is set to a basic command current i so that the deviation of the current from the maximum torque / current curve (MTPA curve) corresponding to the set required loss is equivalent to the required loss. ｄｎ ＊ , i ｑｎ ＊ On the same constant torque curve as ｄｎ ＊ , i ｑｎ ＊ is set to a value obtained by correcting the d-axis component and q-axis component of the above in the direction of magnetization (in FIG. 5, both the d-axis component and the q-axis component are in the positive direction).

[0092] In addition, the demagnetization current i ｄ２ ＊ , i ｑ２ ＊ is set to a basic command current i so that the deviation of the current from the maximum torque / current curve corresponding to the set required loss is equivalent to the required loss. ｄｎ ＊ , i ｑｎ ＊ On the same constant torque curve as ｄｎ ＊ , i ｑｎ ＊ is set to a value obtained by correcting the d-axis component and the q-axis component in the demagnetization direction (in FIG. 5, the d-axis component and the q-axis component are both in the negative direction).

[0093] Furthermore, the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ is the minimum value (minimum salient pole ratio r′) within the range where the estimated salient pole ratio r′ can ensure the accuracy of the magnetic pole position (phase estimated value θ′). ｍ ) so that the basic command current i ｄｎ ＊ , i ｑｎ ＊ On the same constant torque curve as ｄｎ ＊ , i ｑｎ ＊ The second magnetizing current i is set to a value obtained by correcting the d-axis component and the q-axis component of the second magnetizing current i in a predetermined direction (in FIG. 5, the d-axis component and the q-axis component are both in the positive direction). ｄ３ ＊ , i ｑ３ ＊ is set to a value that allows the estimated salient pole ratio r′ to be maintained at a value that enables estimation of the magnetic pole position while suppressing an increase in the rotation speed N and generating a certain amount of loss. ｄｎ ＊ , i ｑｎ ＊ The correction amount (amount of loss) for the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ is defined as a reduced value compared to that of

[0094] Returning to FIG. 4, the warm-up current determination unit 1025 determines the warm-up request signal, the torque command value T ＊ , the estimated rotation speed N′, and the estimated salient pole ratio r′, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ , demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ , and the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ Either of the above is used as the warm-up dq axis current command value i ｄｗ ＊ , i ｑｗ ＊ Output as

[0095] For example, the warm-up current determination unit 1025 determines whether there is a magnetization request and the estimated salient pole ratio r′ is equal to or smaller than the minimum salient pole ratio r ｍ If this is the case, the warm-up dq-axis current command value i ｄｗ ＊ , i ｑｗ ＊ As the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ The presence or absence of a request for magnetization is determined by the torque command value T ＊ and a predetermined torque threshold T ｔｈ , and the rotation speed estimated value N′ and the predetermined rotation speed threshold value N ｔｈ More specifically, the warm-up current determination unit 1025 determines whether the torque command value T ＊ is the torque threshold T ｔｈ , and the estimated rotation speed N′ is equal to or less than the rotation speed threshold N ｔｈ If the estimated saliency ratio r' is equal to or less than the minimum saliency ratio r, it is determined that there is a magnetization request, and otherwise it is determined that there is no magnetization request. ｍ In the above-mentioned scenario, the basic command current i ｄｎ ＊ , i ｑｎ ＊ Even if the first magnetizing current i is corrected to the magnetization side, the salient pole ratio r is maintained at a value that allows estimation of the magnetic pole position (sensorless driving is possible). Therefore, in order to reduce the field weakening while ensuring the loss necessary for warm-up, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ The warm-up dq axis current command value i ｄｗ ＊ , i ｑｗ ＊ It is defined as follows.

[0096] Further, the warm-up current determination unit 1025 determines whether there is a magnetization request and the estimated salient pole ratio r' is smaller than the minimum salient pole ratio r ｍ If it is smaller, the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ The warm-up dq axis current command value i ｄｗ ＊ , iｑｗ ＊ That is, when there is a magnetization request and the salient pole ratio r is below the magnitude that enables estimation of the magnetic pole position, the warm-up dq axis current command value i ｄｗ ＊ , i ｑｗ ＊ The second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ By setting the second magnetizing current i to , a certain amount of loss is generated while reducing the field weakening (while suppressing an increase in the rotation speed N), and the salient pole ratio r is increased, making it possible to estimate the magnetic pole position. ｄ３ ＊ , i ｑ３ ＊ After setting the above, the superposition of the high-frequency current for estimation and the processing in the first estimation unit 191 may be stopped as appropriate.

[0097] Furthermore, the warm-up current determination unit 1025 determines whether or not there is a magnetization request and the estimated salient pole ratio r' is equal to the minimum salient pole ratio r ｍ If this is the case, the warm-up dq-axis current command value i ｄｗ ＊ , i ｑｗ ＊ As the first magnetizing current i ｄ１ ＊ This ensures that the loss required for warm-up is ensured while the salient pole ratio r is maintained at a value that allows sensorless driving.

[0098] On the other hand, the warm-up current determination unit 1025 determines whether there is a magnetization request and the estimated salient pole ratio r' is the minimum salient pole ratio r ｍ If it is smaller, the warm-up dq axis current command value i ｄｗ ＊ , i ｑｗ ＊ As the demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ That is, in this case, the basic command current i is output so as to realize the required loss. ｄｎ ＊ , i ｑｎ ＊Even if the demagnetization side is corrected, the salient pole ratio r is maintained at a value that allows sensorless driving. Therefore, in order to increase the field weakening while ensuring the loss necessary for warm-up, the demagnetization current i ｄ２ ＊ The warm-up dq axis current command value i ｄｗ ＊ , i ｑｗ ＊ It is defined as follows.

[0099] Returning to FIG. 3, the final command current generating unit 103 generates a warm-up request signal and a basic command current i obtained by the basic current command generating unit 101. ｄｎ ＊ , i ｑｎ ＊ , and the warm-up dq-axis current command value i obtained by the warm-up current command generating unit 102 ｄｗ ＊ , i ｑｗ ＊ is input, and the final dq axis current command value i ｄ ＊＊ , i ｑ ＊＊ Calculate.

[0100] More specifically, when it is determined that there is no warm-up request based on the warm-up request signal, the final command current generating unit 103 generates the final dq-axis current command value i ｄ ＊＊ , i ｑ ＊＊ As a result, the basic command current i ｄｎ ＊ , i ｑｎ ＊ On the other hand, when the final command current generating unit 103 determines that there is a warm-up request based on the warm-up request signal, it sets (outputs) the final dq-axis current command value i ｄ ＊＊ , i ｑ ＊＊ As the warm-up dq axis current command value i ｄｗ ＊ , i ｑｗ ＊ Set (output)

[0101] Next, an example of the flow of processing in the current command generating unit 11 (particularly, the warm-up current determining unit 1025 and the final command current generating unit 103) will be described.

[0102] FIG. 6 is a flowchart showing a first example of the processing in the current command generating unit 11.

[0103] As shown in the figure, first, the current command generating unit 11 refers to the warm-up request signal to determine whether or not there is a warm-up request for the battery 21 (S11). Then, if the result of the determination is negative (if there is no warm-up request), the current command generating unit 11 generates the basic command current i ｄｎ ＊ , i ｑｎ ＊ The final dq axis current command value i ｄ ＊＊ , i ｑ ＊＊ (S19), and then this routine ends. On the other hand, if the determination result in S11 is positive (if there is a warm-up request), the processing from S12 onwards is executed.

[0104] In S12, the current command generator 11 (particularly the first magnetizing current generator 1021) generates a torque command value T ＊ and the rotation speed estimated value N′, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ Calculate.

[0105] In S13, the current command generating unit 11 determines whether or not there is a request for magnetization. More specifically, the current command generating unit 11 determines whether or not there is a request for magnetization when the operating point of the motor 200 is equal to or greater than the torque command value T ＊ is the torque threshold T ｔｈ , and the estimated rotation speed N′ is equal to or less than the rotation speed threshold N ｔｈ If the operating point is within the magnetization request region as follows, it is determined that there is a magnetization request (Yes in S13), and if the operating point is not within the magnetization request region, it is determined that there is no magnetization request (No in S13). Then, if the result of the determination is positive, the current command generator 11 executes the processes from S14 onwards, and if the result is negative, it executes the processes from S15 onwards.

[0106] In S14, the current command generator 11 calculates the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ The estimated salient pole ratio r' is calculated from the minimum salient pole ratio rｍ Determine whether it is less than.

[0107] If the result of the determination is affirmative, the current command generator 11 generates the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ The final dq axis current command value i ｄ ＊＊ , i ｑ ＊＊ (S16), and then this routine is terminated. As a result, it is determined that there is a request for magnetization and the salient pole ratio r is equal to or smaller than the minimum salient pole ratio r ｍ If the value is less than the minimum saliency ratio r, the current command value is set to the value required to ensure the estimation accuracy of the magnetic pole position (the saliency ratio r is set to the minimum saliency ratio r ｍ The second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ is output to drive the motor 200. Therefore, it is possible to ensure the accuracy of estimating the magnetic pole position while reducing the field weakening, and also to ensure a certain amount of loss for warming up the battery 21.

[0108] If the result of the determination in S14 is negative, the current command generator 11 sets the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ The final dq axis current command value i ｄ ＊＊ , i ｑ ＊＊ (S17), and then this routine is terminated. As a result, in a situation where there is a magnetization request and the salient pole ratio r is maintained within a range where sensorless drive is possible, the basic command current i is set to 0 so as to ensure the required loss for warm-up. ｄｎ ＊ , i ｑｎ ＊ The first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ is outputted, thereby driving the motor 200. Therefore, it is possible to ensure the accuracy of estimating the magnetic pole position while reducing the field weakening, and also to ensure the required loss for warming up the battery 21.

[0109] On the other hand, in S15, which is executed when the determination result of S13 is negative, the first magnetizing current i calculated in S12 is ｄ１ ＊ , i ｑ１ ＊ The estimated salient pole ratio r' is calculated from the minimum salient pole ratio r ｍ Determine whether it is less than.

[0110] If the result of the determination is affirmative, the current command generating unit 11 generates the demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ The final dq axis current command value i ｄ ＊＊ , i ｑ ＊＊ (S18), and then this routine is terminated. As a result, there is no request for magnetization, and the salient pole ratio r is set to the minimum salient pole ratio r ｍ When the temperature is below 100°C, it is possible to increase the field weakening while ensuring the accuracy of the estimation of the magnetic pole position and to ensure a sufficient amount of loss required for warm-up.

[0111] On the other hand, if the determination result of S15 is affirmative, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ The final dq axis current command value i ｄ ＊＊ , i ｑ ＊＊ (S17), and then this routine is terminated. As a result, in a situation where there is no magnetization request and the salient pole ratio r is maintained within a range where sensorless driving is possible, the current command value is set to the first magnetization current i ｄ１ ＊ , i ｑ１ ＊ Therefore, it is possible to ensure a sufficient amount of loss required for warm-up while ensuring the accuracy of the estimation of the magnetic pole position.

[0112] Fig. 7 is a flowchart showing a second example of the processing in the current command generating unit 11. In Fig. 7, in order to clearly compare the first example with the second example, the same reference numerals are used to denote steps that perform the same processing as in Fig. 6.

[0113] In the second example shown in FIG. 7, when the determination result of S13 is negative (when there is no request for magnetization), the estimated salient pole ratio r′ is equal to or smaller than the minimum salient pole ratio r ｍ The demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ The final dq axis current command value i ｄ ＊＊ , i ｑ ＊＊ As a result, when there is no request for magnetization, the demagnetizing current i that can maintain the salient pole ratio r within the range that allows sensorless drive is set. ｄ２ ＊ , i ｑ２ ＊ is always set, the estimated saliency ratio r′ and the minimum saliency ratio r ｍ By omitting the calculation process relating to the comparison, it is possible to maintain the state in which the field weakening is increased while ensuring a sufficient amount of loss to be used for warming up the battery 21.

[0114] Next, the behavior of the control when the above control algorithm is applied will be described.

[0115] 8 is a timing chart showing an example of the result when the control algorithm according to this embodiment is applied. In the example shown in FIG. 8, at the timing (time t1) when a warm-up request for the battery 21 is detected, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ (shown by the dotted line), the salient pole ratio r (shown by the dotted line) is reduced to the minimum salient pole ratio r ｍ That is, the salient pole ratio r falls below the minimum value at which the estimation accuracy of the magnetic pole position of the motor 200 is ensured, and the control based on the sensorless drive becomes unstable. In response to this, at the time t1 when the warm-up request of the battery 21 is detected, the demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ By setting the minimum saliency ratio r (shown by the solid line), the saliency ratio r (shown by the solid line) increases. ｍSince the salient pole ratio r is maintained at a value exceeding the basic command current i ｄｎ ＊ , i ｑｎ ＊ The battery 21 can be warmed up by generating a loss according to the current correction amount (current deviation amount) for the battery 21 .

[0116] The effects of the motor control method of this embodiment described above will now be summarized.

[0117] According to this embodiment, the current command value (i ｄ ＊＊ , i ｑ ＊＊ ) response current (i ｄｈ , i ｑｈ ) is estimated, and the magnetic pole position (θ′) of the motor 200 is estimated based on the estimated response current, and the estimated magnetic pole position (θ′) and the current command value (i ｄ ＊＊ , i ｑ ＊＊ A motor control method is provided for controlling the power supplied from the battery to the motor based on the power consumption.

[0118] In this motor control method, the operating point (T ＊ , N') to realize the desired efficiency (maximum efficiency) according to the basic command current i ｄｎ ＊ , i ｑｎ ＊ Calculate the basic command current i ｄｎ ＊ , i ｑｎ ＊ is the warm-up current ((i ｄ１ ＊ , i ｑ１ ＊ ) or (i ｄ２ ＊ , i ｑ２ ＊ )) is calculated, and a corrected warm-up current (i ｄ３ ＊ , i ｑ３＊ ) and sets either the warm-up current or the corrected warm-up current as the current command value by referring to the operating parameters of the motor 200.

[0119] As a result, in order to warm up the battery 21, the current command value (i ｄ ＊＊ , i ｑ ＊＊ ) is the basic command current i ｄｎ ＊ , i ｑｎ ＊ In a scene where the salient pole ratio r of motor 200 is changed to generate a loss, it is possible to generate a loss used to warm up battery 21 while maintaining the salient pole ratio r of motor 200 within a range that allows estimation of magnetic pole position (θ'). In other words, since it is possible to ensure the accuracy of estimation of magnetic pole position (θ') while generating a loss used to warm up battery 21, it is possible to achieve suitable drive control (sensorless drive) of motor 200 based on the estimated magnetic pole position (θ').

[0120] In particular, the warm-up current is the basic command current i ｄｎ ＊ , i ｑｎ ＊ The first warm-up current (first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ ) and the basic command current i ｄｎ ＊ , i ｑｎ ＊ The second warm-up current (demagnetization current i ｄ２ ＊ , i ｑ２ ＊ ) and the correction warm-up current (second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ ) is the basic command current i ｄｎ ＊ , i ｑｎ ＊ The first magnetizing current i ｄ１ ＊ , i ｑ１ ＊Then, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ , demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ , and the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ is used as the current command value (i ｄ ＊＊ , i ｑ ＊＊ )

[0121] This allows for sensorless driving while taking into consideration the magnitude of the salient pole ratio r according to the operating state of the motor 200, and the presence or absence of a request for magnetization (whether the field weakening should be reduced or increased), and it is possible to generate losses that can be used to warm up the battery 21.

[0122] In this embodiment, the operating parameters are the torque of the motor 200 (torque command value T ＊ ), the rotation speed of the motor 200 (estimated rotation speed value N′), and the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ The first magnetizing current i is calculated based on whether the operating point of the motor 200 is included in the magnetization request region and the estimated salient pole ratio r'. ｄ１ ＊ , i ｑ１ ＊ , demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ , and the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ is used as the current command value (i ｄ ＊＊ , i ｑ ＊＊ ) is set as the torque command value T ＊ is a predetermined torque threshold T ｔｈand the estimated rotation speed N' is equal to or less than the predetermined rotation speed threshold value N ｔｈ It is defined as the area where:

[0123] As a result, in a scene where the battery 21 is to be warmed up, it is possible to generate losses to be used for warming up the battery 21 while enabling sensorless drive by taking into consideration both the presence or absence of a request for magnetization (whether or not the salient pole ratio r is within a range that can ensure the estimation accuracy of the magnetic pole position) and the actual salient pole ratio r.

[0124] Furthermore, in this embodiment, when the operating point of the motor 200 is included in the magnetization request region, it is determined whether the estimated salient pole ratio r' is equal to or greater than a predetermined salient pole ratio threshold value (Yes in S13 and S14 in FIG. 6). If the estimated salient pole ratio r' is equal to or greater than the salient pole ratio threshold value, the first magnetization current i ｄ１ ＊ , i ｑ１ ＊ current command value (i ｄ ＊＊ , i ｑ ＊＊ On the other hand, if the estimated salient pole ratio r′ is less than the salient pole ratio threshold value, the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ current command value (i ｄ ＊＊ , i ｑ ＊＊ ) (Yes in S14 and S17). The salient pole ratio threshold is set as the minimum salient pole ratio r that can ensure the estimation accuracy of the magnetic pole position (θ′). ｍ It is preferable to set it to .

[0125] As a result, in a situation where the battery 21 is warmed up under a situation where there is a magnetization request, the field weakening is reduced in accordance with the magnetization request, while the salient pole ratio r is maintained at a value that allows estimation of the magnetic pole position (θ′), and the highest possible loss is generated, thereby facilitating the warming up of the battery 21. In particular, in a situation where there is a magnetization request and the salient pole ratio r is maintained within a range that allows sensorless driving, the first magnetization current i ｄ１ ＊ , i ｑ１ ＊By setting the second magnetizing current i, it is possible to secure a sufficient amount of loss (heat generation) used for warming up the battery 21 while reducing the field weakening. On the other hand, in a scene where there is a magnetization request and the salient pole ratio r is not maintained within the range where sensorless driving is possible, the second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ By setting the above, it is possible to adjust the salient pole ratio r to within a range where sensorless drive is possible while ensuring a certain amount of loss for use in warming up the battery 21 while reducing the field weakening.

[0126] In this embodiment, when the operating point of the motor 200 is not included in the magnetization request region, the estimated salient pole ratio r′ is equal to or smaller than a predetermined salient pole ratio threshold value (minimum salient pole ratio r ｍ ) or more (No in S13 and S15 in FIG. 6). Then, it is determined whether the estimated salient pole ratio r' is equal to or greater than the salient pole ratio threshold value (minimum salient pole ratio r ｍ ) or more, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ current command value (i ｄ ＊＊ , i ｑ ＊＊ ) (No in S15 and S17). On the other hand, if the estimated saliency ratio r′ is less than the saliency ratio threshold value (minimum saliency ratio r ｍ ), the demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ current command value (i ｄ ＊＊ , i ｑ ＊＊ ) (Yes in S15 and S18).

[0127] As a result, in a situation where the battery 21 is warmed up in a situation where there is no magnetization request, it is possible to generate as much loss as possible while maintaining the salient pole ratio r at a value that allows estimation of the magnetic pole position (θ′), thereby facilitating the warming up of the battery 21. In particular, in a situation where there is no magnetization request and the salient pole ratio r is maintained within a range where sensorless driving is possible, the first magnetization current i ｄ１ ＊ , i ｑ１ ＊By setting the demagnetizing current i, it is possible to ensure a sufficient amount of loss (heat generation) used for warming up the battery 21. On the other hand, in a situation where there is no request for magnetization and the salient pole ratio r is not maintained within a range where sensorless drive is possible, the demagnetizing current i that can maintain the salient pole ratio r within a range where sensorless drive is possible is set. ｄ２ ＊ , i ｑ２ ＊ By setting the above, it is possible to adjust the salient pole ratio r to within a range where sensorless drive is possible while increasing the field weakening and ensuring a certain amount of loss for use in warming up the battery 21.

[0128] On the other hand, when the operating point of the motor 200 is not included in the magnetization request region, the demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ current command value (i ｄ ＊＊ , i ｑ ＊＊ ) (No in S13 and S18 in FIG. 7).

[0129] That is, in a situation where there is no magnetization request, the demagnetizing current i is generated without comparing the estimated saliency ratio r′ with the saliency ratio threshold value. ｄ２ ＊ , i ｑ２ ＊ current command value (i ｄ ＊＊ , i ｑ ＊＊ ), it is possible to increase the field weakening while reducing the computational load, while maintaining the salient pole ratio r within a range that allows sensorless drive, and ensure a sufficient amount of loss to be used for warming up the battery 21.

[0130] The second magnetizing current i ｄ３ ＊ , i ｑ３ ＊ current command value (i ｄ ＊＊ , i ｑ ＊＊ ), a control logic may be adopted that stops the superposition of the estimation current and the estimation of the magnetic pole position (θ′) (more specifically, the calculation processing in the first estimation unit 191).

[0131] As a result, in a situation where the salient pole ratio r is small and the estimation accuracy of the magnetic pole position (θ') is likely to decrease, the estimation of the magnetic pole position (θ') using the inductance difference between the d and q axes can be stopped, and loss for warm-up can be generated while suppressing an increase in the rotation speed N.

[0132] Furthermore, in this embodiment, the first magnetizing current i ｄ１ ＊ , i ｑ１ ＊ and / or demagnetizing current i ｄ２ ＊ , i ｑ２ ＊ The basic command current i is set to generate a loss obtained by subtracting the loss caused by superimposing the estimation current from the required loss. ｄｎ ＊ , i ｑｎ ＊ It is calculated by correcting the above.

[0133] This prevents the occurrence of loss exceeding the amount necessary for warming up the battery 21, and suppresses a decrease in efficiency.

[0134] Furthermore, this embodiment provides a motor control device 100 suitable for executing the above motor control method.

[0135] Then, the motor control device 100 determines the operating point (T ＊ , N') to realize the desired efficiency (maximum efficiency) according to the basic command current i ｄｎ ＊ , i ｑｎ ＊ a basic command current calculation unit (101) for calculating a basic command current i ｄｎ ＊ , i ｑｎ ＊ is the warm-up current ((i ｄ１ ＊ , i ｑ１ ＊ ) or (i ｄ２ ＊ , i ｑ２ ＊a warm-up current calculation unit (1021, 1022) for calculating a warm-up current (i)) for causing a certain amount of loss used for warm-up while keeping the salient pole ratio of the motor 200 within a predetermined range; ｄ３ ＊ , i ｑ３ ＊ and a current command value setting unit (1025) that sets either the warm-up current or the corrected warm-up current as a current command value by referring to the operating parameters of the motor 200.

[0136] The above describes embodiments of the present invention, but the configurations described in the above embodiments and each modified example only show some of the application examples of the present invention and are not intended to limit the technical scope of the present invention.

Claims

1. A motor control method that estimates a response current to an input of a current command value superimposed with an estimation current, estimates a magnetic pole position of the motor based on the estimated response current, and controls power supplied from a battery to the motor based on the estimated magnetic pole position and the current command value, comprising: calculating a basic command current that achieves a desired efficiency in accordance with an operating point of the motor; calculating a warm-up current that corrects the basic command current so as to generate a required loss for warming up the battery; calculating a corrected warm-up current that causes a certain amount of loss to be used for the warm-up while keeping the salient pole ratio of the motor within a predetermined range; and setting either the warm-up current or the corrected warm-up current as the current command value by referring to operating parameters of the motor.

2. A motor control method as claimed in claim 1, wherein the warm-up current includes a first warm-up current calculated by correcting the basic command current towards the magnetization side, and a second warm-up current calculated by correcting the basic command current towards the demagnetization side, the corrected warm-up current being calculated by correcting the basic command current towards the magnetization side by a correction amount smaller than that of the first warm-up current, and one of the first warm-up current, the second warm-up current, and the corrected warm-up current is set as the current command value according to the operating parameters.

3. A motor control method according to claim 2, wherein the operating parameters include the torque of the motor, the rotational speed of the motor, and an estimated salient pole ratio calculated from the first warm-up current; and one of the first warm-up current, the second warm-up current, and the corrected warm-up current is set as the current command value based on whether or not the operating point of the motor is included in a predetermined magnetization request region and on the estimated salient pole ratio; and the magnetization request region is defined as a region where the torque is equal to or less than a predetermined torque threshold and the rotational speed is equal to or less than a predetermined rotational speed threshold.

4. A motor control method as claimed in claim 3, comprising the steps of: determining whether the estimated salient pole ratio is equal to or greater than a predetermined salient pole ratio threshold when the operating point of the motor is included in the magnetization request region; setting the first warm-up current as the current command value if the estimated salient pole ratio is equal to or greater than the salient pole ratio threshold; and setting the corrected warm-up current as the current command value if the estimated salient pole ratio is less than the salient pole ratio threshold.

5. A motor control method according to claim 3, comprising the steps of: when an operating point of the motor is not included in the magnetization request region, determining whether the estimated salient pole ratio is equal to or greater than a predetermined salient pole ratio threshold; and, if the estimated salient pole ratio is equal to or greater than the salient pole ratio threshold, setting the first warm-up current as the current command value; and, if the estimated salient pole ratio is less than the salient pole ratio threshold, setting the second warm-up current as the current command value.

6. A motor control method according to claim 3, wherein when the operating point of the motor is not included in the magnetization request region, the second warm-up current is set as the current command value.

7. A motor control method according to claim 4 or 5, wherein the salient pole ratio threshold is set to a minimum salient pole ratio that can ensure the estimation accuracy of the magnetic pole position.

8. A motor control method according to any one of claims 3 to 6, wherein when the corrected warm-up current is set as the current command value, the superposition of the estimation current and the estimation of the magnetic pole position are stopped.

9. A motor control method according to claim 2, wherein the first warm-up current and / or the second warm-up current is calculated by correcting the basic command current so as to generate a loss obtained by subtracting a loss caused by superimposing the estimation current from the required loss.

10. A motor control device that estimates a response current to an input of a current command value superimposed with an estimation current, estimates a magnetic pole position of a motor based on the estimated response current, and controls power supplied from a battery to the motor based on the estimated magnetic pole position and the current command value, comprising: a basic command current calculation unit that calculates a basic command current that achieves a desired efficiency in accordance with an operating point of the motor; a warm-up current calculation unit that calculates a warm-up current by correcting the basic command current so as to generate a required loss for warming up the battery; a correction current calculation unit that calculates a corrected warm-up current that causes a certain amount of loss to be used for the warm-up while keeping the salient pole ratio of the motor within a predetermined range; and a current command value setting unit that sets either the warm-up current or the corrected warm-up current as the current command value by referring to operating parameters of the motor.

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