Motor Control Device

Abstract

To enable estimating temperature during motor driving without using a temperature sensor in a motor control device that drives and controls the motor provided with a permanent magnet in a rotor.SOLUTION: A motor control device comprises an electric current command value generation unit 24, a control unit 30, and a temperature estimation unit 50. The electric current command value generation unit generates an electric current command value for allowing the control unit to execute a d-axis zero control. The control unit calculates a d-axis voltage command value and a q-axis voltage command value based on the electric current command value to control a supply power to the motor. The temperature estimation unit detects a d-axis voltage and a q-axis voltage of the motor when the control unit is executing the d-axis zero control to calculate a motor terminal voltage, and estimates an environment temperature based on the motor terminal voltage and a motor rotation speed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a motor control device that drives and controls a motor having a permanent magnet in a rotor. [Background technology]

[0002] Patent Document 1 describes a motor control device that drives and controls a motor with a permanent magnet in its rotor, and estimates the temperature of the motor's magnet based on the motor's rotation speed and induced voltage. This motor control device can estimate the temperature of the motor's magnet without using a temperature sensor or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-108568 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the motor control device described in Patent Document 1 uses induced voltage for temperature estimation, and therefore has the problem that temperature estimation cannot be performed when driving a motor in which induced voltage cannot be detected.

[0005] In other words, the motor control device described in Patent Document 1 can detect the induced voltage and estimate the temperature when the power to the motor is stopped and the motor is rotating freely, but cannot estimate the temperature when the motor is powered and running.

[0006] One aspect of the present disclosure aims to provide a motor control device that drives and controls a motor having a permanent magnet in a rotor, capable of performing temperature estimation when the motor is driven without using a temperature sensor. [Means for solving the problem]

[0007] A motor control device according to one embodiment of the present disclosure is a device that drives and controls a motor (2) having a permanent magnet in its rotor, and includes a current command value generating unit (24), a control unit (30), and a temperature estimating unit (50).

[0008] The current command value generating unit is configured to generate a d-axis current command value and a q-axis current command value in a dq-axis coordinate system as command values ​​required to drive the motor with a target torque. The control unit is configured to calculate a d-axis voltage command value and a q-axis voltage command value required to control the d-axis current and q-axis current of the motor to the d-axis current command value and the q-axis current command value, respectively, and to control the power supplied to the motor based on the calculation results.

[0009] The temperature estimation unit is configured to estimate an environmental temperature around the motor based on a control state of the motor by the control unit. In particular, the current command value generating unit is configured to cause the control unit to execute d-axis zero control by setting the d-axis current command value to zero, and the temperature estimating unit calculates the motor terminal voltage by detecting the d-axis voltage and the q-axis voltage of the motor when the control unit is executing the d-axis zero control, and the temperature estimating unit estimates the environmental temperature based on the calculated motor terminal voltage and the rotation speed of the motor.

[0010] In this manner, the motor control device of the present disclosure estimates the environmental temperature around the motor based on the motor terminal voltage and the motor rotation speed, making it possible to estimate the environmental temperature when the motor is being driven by current flow, rather than when the motor is idling. [Brief description of the drawings]

[0011] [Figure 1] 1 is a block diagram showing an overall configuration of a motor control device according to an embodiment; [Diagram 2] 5 is a diagram illustrating the relationship between air density, which changes depending on the environmental temperature, and fan torque. FIG. [Diagram 3] FIG. 11 is an explanatory diagram illustrating a map used to estimate an environmental temperature when d-axis zero control is executed. [Figure 4] FIG. 4 is an explanatory diagram illustrating a map used to estimate an environmental temperature when flux-weakening control is performed; [Diagram 5] 4 is a flowchart showing a motor control process executed by a control circuit. [Figure 6] 10 is a flowchart illustrating a modified example of the motor control process. [Figure 7] 11 is an explanatory diagram illustrating a modified example of a motor control device in which the load torque changes depending on the environmental temperature. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. [Embodiment] <Configuration> As shown in Fig. 1, a motor control device 10 of this embodiment is for controlling the drive of a three-phase synchronous motor (hereinafter, motor) 2 having a permanent magnet in its rotor. The motor control device 10 includes a rotation sensor 12, an inverter 14, and a control circuit 20. In this embodiment, the motor 2 is a fan motor that rotates a blower fan.

[0013] The rotation sensor 12 is configured to generate a pulse signal for each predetermined rotation angle of the motor 2, thereby detecting the rotation angle of the motor 2 (that is, the rotation position). Moreover, the inverter 14 is configured with a well-known bridge circuit having a high-side switch and a low-side switch respectively provided between the terminals of each phase U, V, W of the motor 2 and the positive and negative sides of a DC power source (e.g., a battery).

[0014] Since the configurations of the rotation sensor 12 and the inverter 14 are well known, detailed description thereof will be omitted here. Next, the control circuit 20 is for controlling the rotation speed of the motor 2 to a target rotation speed, and is provided with a microcomputer including a CPU and a semiconductor memory such as a RAM or a ROM (hereinafter, referred to as a memory).

[0015] The control circuit 20 realizes the functions of a required torque generation unit 22, a current command value generation unit 24, a three-phase / two-phase conversion unit 26, a current control unit 30, a two-phase / three-phase conversion unit 32, a PWM modulation unit 34, and a flux-weakening control unit 40 by the CPU executing a program.

[0016] Here, the required torque generation unit 22 has a function of generating a target torque for controlling the rotation speed of the motor 2 to a target rotation speed as a required torque. In addition, the current command value generating unit 24 has a function of generating a d-axis current command value and a q-axis current command value in the dq-axis coordinate system as command values ​​required to drive the motor with a target torque based on the required torque calculated by the required torque generating unit 22, and outputting them to the current control unit 30.

[0017] The dq-axis coordinate system is a well-known rotating coordinate system in which the magnetic flux direction of the permanent magnet of the rotor is the d-axis, and the direction perpendicular to the d-axis and generating torque in the rotor is the q-axis. The current command value generating unit 24 sets the d-axis current command value out of the d-axis current command value and the q-axis current command value to zero, thereby causing the current control unit 30 to execute d-axis zero control.

[0018] Next, the three-phase / two-phase conversion unit 26 has a function of detecting the current (hereinafter referred to as three-phase current) flowing from the inverter 14 to each phase U, V, and W of the motor 2, and converting the three-phase current into a d-axis current and a q-axis current based on the detection signal from the rotation sensor 12.

[0019] The current control unit 30 has a function of calculating a d-axis voltage command value and a q-axis voltage command value based on the deviation between the d-axis current and the q-axis current converted by the three-phase / two-phase conversion unit 26 and the d-axis current command value and the q-axis current command value generated by the current command value generation unit 24.

[0020] The d-axis voltage command value and the q-axis voltage command value are voltage command values ​​required to control the d-axis current and the q-axis current to the d-axis current command value and the q-axis current command value, respectively, and are output to the two-phase / three-phase conversion unit 32.

[0021] The two-phase / three-phase conversion unit 32 has a function of generating a three-phase voltage command value by performing coordinate conversion on the d-axis voltage command value and the q-axis voltage command value calculated by the current control unit 30. Then, the generated three-phase voltage command value is output to the PWM modulation unit 34.

[0022] The PWM modulation unit 34 has a function for PWM controlling the actual voltages output to the terminals of the U, V, and W phases of the motor 2 in accordance with the three-phase voltage command value. As a result, a control signal for PWM controlling the voltages of the U, V, and W phases is output from the PWM modulation unit 34 to each switch constituting the inverter 14, switching the on / off state of each switch, and controlling the power supplied to each phase of the motor 2.

[0023] Next, the flux-weakening control unit 40 has a function of setting the d-axis current command value to a negative current value that weakens the magnetic flux of the permanent magnet and outputting it to the current control unit 30 when the d-axis zero control by the current control unit 30 is unable to cause the rotational speed of the motor 2 to reach the target rotational speed.

[0024] That is, the flux-weakening control unit 40 switches the motor control by the current control unit 30 from the above-mentioned d-axis zero control to flux-weakening control by inputting the d-axis current command value to the current control unit 30. As a result, when the rotation speed of the motor 2 cannot reach the target rotation speed by the d-axis zero control, the motor control is switched to flux-weakening control, and it becomes possible to increase the rotation speed of the motor 2 to the target rotation speed.

[0025] The d-axis zero control and flux-weakening control of the motor 2 are publicly known techniques, as described in, for example, JP 2004-194406 A and JP 2014-68443 A, and therefore will not be described in detail here.

[0026] In this embodiment, the current command value generation unit 24 and the field weakening control unit 40 correspond to an example of the current command value generation unit of the present disclosure, and the current control unit 30 corresponds to an example of the control unit of the present disclosure.

[0027] Next, the control circuit 20 is further provided with a temperature estimation unit 50 as a function realized by the CPU executing a program. The temperature estimation unit 50 is a function of estimating the ambient temperature around the motor 2 when d-axis zero control or field weakening control is being executed by the function of the current control unit 30. Different estimation methods are used for estimating the ambient temperature when d-axis zero control is executed and when field weakening control is executed. Hereinafter, the method for estimating the ambient temperature implemented for each of these controls will be described.

[0028] <Method for estimating ambient temperature in d-axis zero control> When the motor 2 is driven by d-axis zero control, the motor terminal voltage V a can be described by the following equation (1) with the electrical angular velocity ω, the winding resistance R a , the winding inductance L, and the induced voltage constant K e as parameters.

[0029]

Equation

[0030] However, in Equation (1), V B is the battery voltage, V UF is the maximum voltage utilization constant, and i q is the q-axis current. In the above Equation (1), the winding resistance R a , and the induced voltage constant K e have temperature dependence and can be described as in the following equations (2) and (3).

[0031]

Equation

[0032] In equations (2) and (3), T0 is the reference temperature, T a represents the ambient temperature (i.e., the environmental temperature). In equation (2), R a0 is the winding resistance at the reference temperature, α T is the resistance temperature coefficient of the winding, △R a represents the temperature rise due to the heat generated by the winding. In addition, in equation (3), K e0 is the induced voltage constant at the reference temperature, α B represents the temperature coefficient of magnetic flux density of a permanent magnet.

[0033] In addition, as shown in FIG. 2, the air density ρ changes with temperature, so the required torque changes even when the motor 2 is operated at the same rotation speed. In FIG. 2, T0 is a reference temperature, ρ0 is the air density at the reference temperature, and T r0 is the reference torque of the fan, T r represents the actual torque of the fan.

[0034] Therefore, the q-axis current i required to drive the motor 2 with the desired fan torque is q The actual torque T r can be written as equation (5), and the air density ρ in equation (5) can be written as equation (6).

[0035]

number

[0036] According to the above relational expressions (1) to (6), the temperature dependency of the motor terminal voltage can be described as shown in FIG. 3, on the condition that the electrical angular velocity ω, in other words, the rotational speed Nm of the motor 2, is constant.

[0037] In other words, assuming that the rotation speed Nm of the motor 2 is constant, in other words, that the motor 2 is not accelerating or decelerating, the motor terminal voltage has an environmental temperature dependency, that is, the higher the environmental temperature, the lower the motor terminal voltage becomes, as shown in FIG. 3.

[0038] Therefore, the environmental temperature around the motor 2 is determined based on the motor terminal voltage vs. environmental temperature characteristics shown in Figure 3. a and the rotation speed Nm of the motor 2. Therefore, in the temperature estimation unit 50, the voltages of the phases U, V, and W of the motor 2 are three-phase / two-phase converted to obtain the d-axis voltage V d and q-axis voltage V q In equations (7) and (8), θ1 represents the reference electrical angle (i.e., the rotational position of the rotor).

[0039]

number

[0040] Then, in the temperature estimation unit 50, the d-axis voltage V d and q-axis voltage V q Then, the motor terminal voltage V a Calculate the motor terminal voltage V a and the rotation speed Nm of the motor 2. Note that, for estimating the environmental temperature, a map that is set in advance based on the motor terminal voltage-environmental temperature characteristics shown in FIG.

[0041] <Method of estimating environmental temperature in flux-weakening control> In the flux-weakening control, the d-axis current is set, so the motor terminal voltage V a Therefore, when the flux-weakening control is executed, the temperature estimator 50 estimates the environmental temperature by utilizing the temperature dependency of the d-axis current.

[0042] In other words, the q-axis current i q can be written as in equation (4) above. The actual torque T of the fan in equation (4) r can be written as equations (5) and (6), and the induced voltage constant K eSince can be expressed as equation (3), the temperature dependence of the q-axis current is as shown in Figure 4.

[0043] Therefore, in the temperature estimation unit 50, when the rotational speed Nm of the motor 2 is constant, in other words, when the motor 2 is not accelerating or decelerating, the temperature estimation unit 50 obtains the q-axis current from the three-phase / two-phase conversion unit 26, and estimates the environmental temperature using the obtained q-axis current and a preset map.

[0044] In addition, to estimate the environmental temperature under the flux-weakening control, a map that is preset based on the q-axis current-environmental temperature characteristics shown in FIG. 4 is used, and the temperature estimator 50 estimates the environmental temperature based on the q-axis current and the rotation speed Nm of the motor 2.

[0045] <Processing> Next, a motor control process executed in the control circuit 20 to drive and control the motor 2 using the above-mentioned d-axis zero control or flux-weakening control will be described with reference to the flowchart shown in FIG.

[0046] 5, in the motor control process, a first control process is executed in S110 to drive the motor 2 with the above-mentioned d-axis zero control. Note that this first control process is a process that realizes the functions of the required torque generation unit 22, the current command value generation unit 24, the three-phase / two-phase conversion unit 26, the current control unit 30, and the two-phase / three-phase conversion unit 32.

[0047] For this reason, in S110, the torque required to control the motor 2 to the target rotation speed is calculated, and the q-axis current command value is calculated from the required torque. Then, voltage command values ​​for the q-axis voltage and the d-axis voltage are calculated from the calculation result and the d-axis current command value of zero, and converted into three-phase voltages.

[0048] As a result, a control signal is output from the PWM modulation unit 34 to the inverter 14 in synchronization with the rotation angle of the motor 2 detected by the rotation sensor 12, the power supplied to the motor 2 is controlled, and the rotational torque and therefore the rotational speed of the motor 2 are controlled to the target value.

[0049] Next, when the control process of S110 is executed, the process proceeds to S120, where it is determined whether or not the rotation speed of the motor 2 has reached the target rotation speed. Then, when it is determined in S120 that the rotation speed of the motor 2 has reached the target rotation speed, the process proceeds to S130, where it is determined whether or not the estimation condition for the environmental temperature is satisfied, that is, whether or not the rotation speed of the motor 2 is constant and is not being accelerated or decelerated.

[0050] In S130, if the motor 2 is not accelerated or decelerated and the rotation speed is constant, it is determined that the environmental temperature estimation condition is satisfied, and the process proceeds to S140. If it is determined that the environmental temperature estimation condition is not satisfied in S130, the motor control process is temporarily terminated. After the motor control process is terminated, the process proceeds to S110 again to repeatedly execute the motor control process.

[0051] Next, in S140, the d-axis voltage and q-axis voltage are calculated from the voltages of the phases U, V, and W of the motor 2 using the above-mentioned equations (7) and (8), and the motor terminal voltage is calculated from the calculation results using equation (9). Also in S140, the rotation speed of the motor 2 is acquired via the rotation sensor 12.

[0052] Then, in the next S150, the environmental temperature is estimated based on the motor terminal voltage calculated in S140 and the rotation speed of the motor 2, using a map for environmental temperature estimation that is set in advance based on the motor terminal voltage-environmental temperature characteristics shown in Fig. 3, and the motor control process is temporarily terminated. Note that in S150, the result of the environmental temperature estimation is stored in a non-volatile memory.

[0053] Next, if it is determined in S120 that the rotational speed of motor 2 has not reached the target rotational speed, that is, if the control process of S110 is executed but the rotational speed of motor 2 cannot be increased to the target rotational speed, the process proceeds to S160.

[0054] In S160, a second control process is executed to drive the motor 2 by the above-mentioned flux-weakening control. The second control process is a process for realizing the function of the flux-weakening control unit 40 in addition to the first control process, and changes the d-axis current command value from zero so that the rotation speed of the motor 2 can be controlled to the target rotation speed, and calculates voltage command values ​​for the q-axis voltage and the d-axis voltage. Then, the calculated voltage command values ​​for the q-axis voltage and the d-axis voltage are converted into three-phase voltages and output to the PWM modulation unit 34.

[0055] Next, when the second control process is executed in S160, the process proceeds to S170. In S170, similar to S130 described above, it is determined whether or not the conditions for estimating the environmental temperature are satisfied, that is, whether or not the rotation speed of the motor 2 is constant and is not being accelerated or decelerated.

[0056] If it is determined in S170 that the conditions for estimating the environmental temperature are met, the process proceeds to S180. If it is determined in S170 that the conditions for estimating the environmental temperature are not met, the motor control process is temporarily terminated.

[0057] In S180, the q-axis current obtained by the function of the three-phase / two-phase conversion unit 26 described above and the rotation speed of the motor 2 obtained via the rotation sensor 12 are obtained, and the process proceeds to S190.

[0058] Then, in the next S190, the environmental temperature is estimated based on the q-axis current and rotation speed acquired in S180, using a map for environmental temperature estimation that was set in advance based on the q-axis current-environmental temperature characteristics shown in Figure 4, and the motor control process is temporarily terminated. Note that in S190, as in S150, the result of the environmental temperature estimation is stored in a non-volatile memory.

[0059] Incidentally, as described above, once the motor control process is terminated, the process proceeds to S110 again to repeatedly execute the motor control process. However, if the d-axis current command value is a negative value smaller than 0 A, the process may proceed to S160.

[0060] In other words, when the d-axis current command value is a negative value smaller than 0 A, since flux-weakening control is being executed, once the motor control process is terminated, the process may proceed to S160 instead of S110 and flux-weakening control may be executed.

[0061] The processes of S130 to S150 and S170 to S190 function as the temperature estimation section 50 and correspond to an example of the temperature estimation section of the present disclosure. <Effects> As described above, in the motor control device 10 of this embodiment, the control circuit 20 is configured to control the driving of the motor 2 by d-axis zero control or flux-weakening control. Then, when the motor 2 is controlled to be driven by the d-axis zero control and when the motor 2 is controlled to be driven by the flux-weakening control, the method of estimating the environmental temperature is switched to estimate the environmental temperature.

[0062] In other words, in the d-axis zero control, the d-axis current that does not contribute to torque is not passed, so the current for the target torque is minimized and it is possible to efficiently drive the motor 2. When the motor 2 is driven by this d-axis zero control, the motor terminal voltage has temperature dependency, so the motor terminal voltage is calculated as described above, and the environmental temperature is estimated based on the calculation result and the rotation speed of the motor 2.

[0063] On the other hand, in flux-weakening control, when the rotation speed of motor 2 cannot be increased to the target rotation speed by d-axis zero control, the induced voltage generated by the rotation of motor 2 is suppressed by applying the d-axis current in the negative direction, thereby increasing the output torque. Since this flux-weakening control controls the motor terminal voltage to be constant, it is not possible to estimate the environmental temperature in the same manner as d-axis zero control. Therefore, in flux-weakening control, the rate of change of the q-axis current with respect to temperature increases due to the temperature characteristics of the load torque and magnet magnetic flux, and the environmental temperature is estimated based on the q-axis current and the rotation speed of motor 2 as described above.

[0064] Therefore, according to the motor control device 10 of this embodiment, it is possible to estimate the environmental temperature without using a temperature sensor or the like, whether the motor 2 is driven by d-axis zero control or by flux-weakening control.

[0065] In this embodiment, the estimated environmental temperature is stored in non-volatile memory in S150 and S190, and the environmental temperature stored in the memory can be used as the usage history of motor 2 to estimate the lifespan of motor 2.

[0066] The result of estimating the environmental temperature can also be used to change the control parameters when controlling the drive of the motor in accordance with the estimated environmental temperature. [Other embodiments] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can be implemented in various modified forms.

[0067] For example, in the above embodiment, a description has been given of the motor control device 10 configured to switch between d-axis zero control and flux-weakening control depending on the drive state of the motor 2. However, the environmental temperature estimation technique of the present disclosure can be applied in the same manner as in the above embodiment even when the motor control device 10 is configured to drive and control the motor 2 using only d-axis zero control.

[0068] In other words, when the motor control device is configured to drive and control the motor 2 using only the d-axis zero control, the function of the flux-weakening control unit 40 shown in Fig. 1 is eliminated. Therefore, as shown in Fig. 6, in the motor control process, the processes of S160 to S190 shown in Fig. 5 are not necessary, and it is sufficient to execute the processes of S110 and S130 to S150.

[0069] Next, in the above embodiment, the motor 2 is a fan motor, and the fan torque changes due to a change in air density accompanying a change in the environmental temperature. However, the environmental temperature estimation technology of the present disclosure can be applied in the same manner as in the above embodiment to any motor whose load torque changes due to a change in the environmental temperature, as shown in FIG.

[0070] Examples of motors whose load torque changes with changes in environmental temperature include fluid motors used to stir fluids such as water, and drive motors in which the load torque of a driven object such as a gear changes with temperature.

[0071] The control method by the control circuit 20, including the method for estimating the environmental temperature, may be realized by a dedicated computer provided by configuring a processor and a memory programmed to execute one or more functions embodied in a computer program. Alternatively, the control method by the control circuit 20 may be realized by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control method by the control circuit 20 may be realized by one or more dedicated computers configured by a combination of a processor and a memory programmed to execute one or more functions and a processor configured with one or more hardware logic circuits.

[0072] In addition, the computer program executed in the control circuit 20 may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by a computer. In addition, the method for realizing the functions of each unit included in the control circuit 20 does not necessarily need to include software, and all of the functions may be realized using one or more pieces of hardware.

[0073] In addition, multiple functions possessed by one component in the above embodiments may be realized by multiple components, or one function possessed by one component may be realized by multiple components. Also, multiple functions possessed by multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0074] In addition to the motor control device described above, the present disclosure can be realized in various forms, such as a system that includes the motor control device as a component, a program for causing a computer to function as the motor control device, a non-transient physical recording medium such as a semiconductor memory on which the program is recorded, and an environmental temperature estimation method in a motor control device. [Explanation of symbols]

[0075] 2... motor, 10... motor control device, 24... current command value generating unit, 30... current control unit, 40... flux-weakening control unit, 50... temperature estimating unit.

Claims

1. A motor control device that drives and controls a motor having a permanent magnet in a rotor, a current command value generating unit configured to generate a d-axis current command value and a q-axis current command value in a d-q axis coordinate system as command values ​​required to drive the motor with a target torque; a control unit configured to calculate a d-axis voltage command value and a q-axis voltage command value required to control a d-axis current and a q-axis current of the motor to the d-axis current command value and the q-axis current command value, respectively, and to control power supplied to the motor based on the calculation result; a temperature estimation unit configured to estimate an environmental temperature around the motor based on a control state of the motor by the control unit; Equipped with the current command value generation unit is configured to cause the control unit to execute d-axis zero control by setting the d-axis current command value to zero; the temperature estimation unit is configured to calculate a motor terminal voltage by detecting a d-axis voltage and a q-axis voltage of the motor when the control unit is executing the d-axis zero control, and to estimate the environmental temperature based on the motor terminal voltage and a rotational speed of the motor by using a map having the motor terminal voltage, the environmental temperature, and the rotational speed of the motor as parameters; Moreover, the map is set based on the motor terminal voltage-environmental temperature characteristic which represents the relationship between the environmental temperature and the motor terminal voltage for each rotational speed of the motor, and the temperature estimation unit estimates the environmental temperature using the map when the rotational speed of the motor is constant and is not accelerating or decelerating.

2. 2. The motor control device according to claim 1, the current command value generation unit is configured to cause the control unit to execute flux-weakening control by setting a negative current command value as the d-axis current command value when the target torque cannot be reached through the d-axis zero control by the control unit, the temperature estimation unit is configured to detect the q-axis current of the motor when the control unit is executing the flux-weakening control, and estimate the environmental temperature based on the q-axis current and the rotational speed of the motor using a map with the q-axis current, the environmental temperature, and the rotational speed of the motor as parameters.

3. 3. The motor control device according to claim 1, A motor control device, wherein the motor is a fan motor that rotates a fan.

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