Drive device

Abstract

To raise the temperature of a power storage device while suppressing an increase in noise and vibration of a motor.SOLUTION: When a temperature increase condition of the power storage device is satisfied, and when a rotation speed of the motor is within a first range in which noise and vibration of the motor become a problem due to an electromagnetic force of an electric 6m (m = 1, 2,.) order, set a current advance angle so as to achieve both reduction of the electromagnetic force of the electric 6m order and heat generation amounts of the motor and the inverters; When the rotation speed is within a second range in which noise and vibration of the motor become a problem due to an electromagnetic compelling force of an electric 2n (n = 1, 2,.) order, the current advance angle is set so as to achieve both reduction of the electromagnetic compelling force of the electric 2n order and heat generation amounts of the motor and the inverters.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a drive device. [Background technology]

[0002] A technology has been proposed in the past that includes a compressor having a compression unit that compresses a refrigerant and a drive motor that drives the compression unit, and that raises the temperature of the refrigerant using waste heat generated by driving the drive motor, and a blower that blows air to a heat exchanger that receives heat from the refrigerant and raises its temperature, and then blows the air that has exchanged heat with the heat exchanger into the vehicle interior (see, for example, Patent Document 1).In this technology, when the blower is in a driving state, the current phase is controlled to a phase that reduces the rate at which the output of the drive motor changes relative to changes in the current phase of the drive motor; specifically, the current phase of the drive motor is controlled to be more retarded than the optimal phase, thereby driving the drive motor inefficiently. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-59152 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-described technology, depending on the current phase when the drive motor is driven inefficiently, there is a possibility that noise and vibration of the motor may increase due to electromagnetic forces of the electric 6m (m = 1, 2,...) order or the electric 2n (n = 1, 2,...) order of the motor. The drive device of the present disclosure has a primary objective of raising the temperature of the power storage device while suppressing increases in motor noise and vibration. [Means for solving the problem]

[0005] The drive device of the present disclosure employs the following measures to achieve the above-described primary object. The drive device of the present disclosure includes a power storage device, a motor, an inverter provided between the power storage device and the motor, a heat transfer device that transfers heat from the motor and / or the inverter to the power storage device, and a control device that controls the inverter using a current advance angle based on a torque command of the motor, wherein, when a temperature rise condition of the power storage device is met, if the rotation speed of the motor is within a first range in which noise and vibration of the motor become a problem due to electromagnetic forcing forces of electrical 6m (m = 1, 2, . . .), the control device sets the current advance angle so as to both reduce the electromagnetic forcing force of electrical 6m (m = 1, 2, . . .) and increase the heat generation amount of the motor and the inverter, and if the rotation speed is within a second range in which noise and vibration of the motor become a problem due to electromagnetic forcing forces of electrical 2n (n = 1, 2, . . . ), the control device sets the current advance angle so as to both reduce the electromagnetic forcing force of electrical 2n (n = 1, 2, . . . ) and increase the heat generation amount of the motor and the inverter. This process makes it possible to raise the temperature of the energy storage device while suppressing increases in motor noise and vibration, depending on whether the electromagnetic forcing force of the electrical 6mth order or the electromagnetic forcing force of the electrical 2nth order is the issue. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a schematic diagram of an electric vehicle 10 equipped with a drive device according to an embodiment. [Figure 2] 10 is a flowchart illustrating an example of a processing routine. [Figure 3] FIG. 10 is an explanatory diagram showing an example of the relationship between the current advance angle θi, the torque command Tm*, and the electrical 6m-th and electrical 2n-th order electromagnetic forcing forces Fem. DETAILED DESCRIPTION OF THE INVENTION

[0007] A mode (embodiment) for carrying out the present disclosure will be described with reference to the drawings. Fig. 1 is a schematic diagram of an electric vehicle 10 equipped with a drive device according to an embodiment of the present disclosure. As shown in the figure, the electric vehicle 10 according to the embodiment includes a motor 22, an inverter 24, a battery 26 as an electricity storage device, a cooling device 40 as a heat transfer device, and an electronic control unit (hereinafter referred to as "ECU") 50 as a control device.

[0008] The motor 22 is configured as a three-phase AC motor and includes a rotor with a permanent magnet embedded in a rotor core and a stator with three-phase (U-phase, V-phase, and W-phase) coils wound around a stator core. The rotor of the motor 22 is connected to a drive shaft 16 that is coupled to the drive wheels 12a and 12b via a differential gear 14. The inverter 24 is connected to power lines 28 (positive line 28p and negative line 28n) that are connected to a battery 26. The inverter 24 includes six transistors T11 to T16 as switching elements and six diodes D11 to D16 connected in parallel to the six transistors T11 to T16, respectively. The transistors T11 to T16 are arranged in pairs, two on the source side and two on the sink side of the positive line 28p and the negative line 28n. Each of the connection points of two pairs of transistors T11-T16 is connected to a three-phase (U-phase, V-phase, W-phase) coil of the motor 22. Therefore, the ECU 50 adjusts the proportion of the on-time of the paired transistors T11-T16, thereby generating a rotating magnetic field in the three-phase coil of the motor 22 and rotating the motor 22 (rotor). The battery 26 is configured as, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery. The positive and negative terminals of the battery 26 are connected to a positive line 28p and a negative line 28n. A smoothing capacitor 30 is connected to the positive line 28p and the negative line 28n. The cooling device 40 includes a circulation flow path 42, a radiator 44, and an electric pump 46. The circulation flow path 42 is configured as a flow path for circulating coolant through the motor 22, the inverter 24, the battery 26, and the radiator 44 in this order. The electric pump 46 pumps (circulates) the cooling water in the circulation flow path 42. The circulation flow path 42 may be configured as a flow path for circulating the cooling water through the inverter 24, the motor 22, the battery 26, and the radiator 44 in this order.

[0009] The ECU 50 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, as well as various drive circuits and logic ICs. The ECU 50 receives signals from various sensors. For example, the ECU 50 receives the rotational position θm of the rotor of the motor 22 from the rotational position sensor 22a and the phase currents Iu, Iv, and Iw of the motor 22 from the current sensors 22u, 22v, and 22w. The ECU 50 also receives the voltage Vb of the battery 26 from the voltage sensor 26v, the current Ib of the battery 26 from the current sensor 26i, and the temperature Tb of the battery 26 from the temperature sensor 26t. The ECU 50 also receives the voltage VH of the capacitor 30 from the voltage sensor 30v and the temperature Tc of the cooling water in the circulation flow path 42 of the cooling device 40 from the temperature sensor 48. Also input to the ECU 50 are an on / off signal from a power switch 60, the operating position of a shift lever 61 (shift position SP) from a shift position sensor 62, the depression amount of an accelerator pedal 63 (accelerator opening Acc) from an accelerator pedal position sensor 64, the depression amount of a brake pedal 65 (brake pedal position BP) from a brake pedal position sensor 66, and a vehicle speed V from a vehicle speed sensor 67. The ECU 50 outputs switching control signals to transistors T11 to T16 of the inverter 24 and a control signal to the electric pump 46. The ECU 50 calculates the electrical angle θe and rotation speed Nm of the motor 22 based on the rotational position θm of the rotor of the motor 22, and calculates the charge storage rate SOC of the battery 26 based on the integrated value of the current Ib of the battery 26.

[0010] In the electric vehicle 10 of this embodiment, the ECU 50 sets a required torque Td* (required of the drive shaft 16) required for traveling based on the accelerator pedal position Acc and the vehicle speed V, sets a torque command Tm* for the motor 22 so that the vehicle travels at the set required torque Td*, and performs switching control of the transistors T11 to T16 of the inverter 24 based on the set torque command Tm*. The control of the inverter 24 will now be described. The ECU 50 performs coordinate transformation (three-phase to two-phase transformation) of the phase currents Iu, Iv, and Iw of the motor 22 into d-axis and q-axis currents Id and Iq using the electrical angle θe of the motor 22. Next, the ECU 50 sets a current advance angle θi and an effective current value Ir based on the torque command Tm* for the motor 22, and sets the d-axis and q-axis current commands Id* and Iq* based on the set current advance angle θi and effective current value Ir. The current lead angle θi is the angle (lead angle amount) of a current command vector with respect to the q axis, the components of which are d-axis and q-axis current commands Id* and Iq* in a dq coordinate system, and the effective current value Ir is the square root of the sum of the square of the d-axis current command Id* and the square of the q-axis current command Iq*. Then, d-axis and q-axis voltage commands Vd* and Vq* are calculated by current feedback control so that the differences between the d-axis and q-axis current commands Id* and Iq* and the currents Id and Iq are canceled out. Additionally, the d-axis and q-axis voltage commands Vd* and Vq* are coordinate-transformed (two-phase to three-phase transformation) using the electrical angle θe of the motor 22 to voltage commands Vu*, Vv*, and Vw* for each phase. These voltage commands Vu*, Vv*, and Vw are compared with the carrier voltage to generate PWM signals for the transistors T11 to T16, thereby controlling the switching of the transistors T11 to T16.

[0011] Next, the operation of the electric vehicle 10 according to this embodiment, particularly the process for setting the current advance angle θi and the effective current value Ir, will be described. FIG. 2 is a flowchart illustrating an example of a process routine repeatedly executed by the ECU 50. When this routine is executed, the ECU 50 first determines whether a temperature increase condition for the battery 26 is met (step S100). The temperature increase condition for the battery 26 is met, for example, when the temperature Tb of the battery 26 is equal to or lower than a threshold value Tblo, or when a user operation (such as a switch operation) requests a temperature increase for the battery 26. If it is determined in step S100 that the temperature increase condition for the battery 26 is not met, the ECU 50 sets the current advance angle θi to a value θi1 (step S140), and sets the effective current value Ir based on the set current advance angle θi and torque command Tm* (step S190), thereby terminating this routine. The value θi1 is determined as the value that minimizes the effective current value Ir among the combinations of the current advance angle θi and the effective current value Ir for outputting the torque command Tm* from the motor 22.

[0012] If it is determined in step S100 that the temperature rise condition of the battery 26 is satisfied, it is then determined whether or not a noise vibration (NV) condition, which indicates that noise and vibration of the motor 22 are an issue, is satisfied (step S110). The NV condition is satisfied, for example, when the rotation speed Nm of the motor 22 is within a predetermined rotation speed range. The predetermined rotation speed range includes a first and a second rotation speed range. The first rotation speed range is determined in advance through experiments, analysis, etc. as a rotation speed range in which noise and vibration of the motor 22 are an issue due to electromagnetic forcing forces of the electrical 6m (m = 1, 2, . . .) order. The second rotation speed range is determined in advance through experiments, analysis, etc. as a rotation speed range in which noise and vibration of the motor are an issue due to electromagnetic forcing forces of the electrical 2n (n = 1, 2, . . .) order. The electromagnetic forcing forces of the electrical 6m order are electromagnetic forcing forces based on harmonic components of the phase currents Iu, Iv, and Iw of the motor 22. The electrical 2n-th order electromagnetic forcing force is an electromagnetic forcing force based on the fundamental wave components of the phase currents Iu, Iv, and Iw of the motor 22, and is easily exacerbated by imbalances in the phase currents Iu, Iv, and Iw. Note that the rotation speed range in which noise and vibration of the motor 22 become an issue due to the electrical 6m-th order and electrical 2n-th order electromagnetic forcing forces is included in either the first rotation speed range or the second rotation speed range, depending on which of the electrical 6m-th order and electrical 2n-th order electromagnetic forcing forces poses the greater issue.

[0013] If it is determined in step S110 that the NV problem condition is not satisfied, the current advance angle θi is set to a value θi2 (step S150), the effective current value Ir is set based on the set current advance angle θii and the torque command Tm* (step S190), and this routine ends. The value θi2 is determined, for example, as a value that, among the combinations of the current advance angle θi and the effective current value Ir for outputting the torque command Tm* from the motor 22, increases the effective current value Ir compared to the value θi1, thereby increasing the amount of heat generated by the motor 22 and the inverter 24. This increases the amount of heat generated by the motor 22 and the inverter 24, allowing the temperature of the battery 26 to be raised via the cooling device 40.

[0014] If it is determined in step S110 that the NV problem condition is met, it is determined whether the rotation speed Nm of the motor 22 is within a first rotation speed range (a rotation speed range in which noise and vibration of the motor 22 become a problem due to electromagnetic forcing of electrical 6mth order) (step S120), and it is also determined whether the rotation speed Nm of the motor 22 is within a second rotation speed range (a rotation speed range in which noise and vibration of the motor 22 become a problem due to electromagnetic forcing of electrical 2nth order) (step S130).If it is determined in step S120 that the rotation speed Nm of the motor 22 is within the first rotation speed range, the current advance angle θi is set to a value θi3 (step S160).If it is determined in step S130 that the rotation speed Nm of the motor 22 is within the second rotation speed range, the current advance angle θi is set to a value θi4 (step S170). If it is determined in steps S120 and S130 that the rotation speed Nm1 of the motor 22 is outside the first or second rotation speed range, the current advance angle θi is set to a value θi5 (step S180). The values ​​θi3 to θi5 will be described later. After the current advance angle θi is set in this manner, the effective current value Ir is set based on the set current advance angle θii and torque command Tm* (step S190), and this routine ends.

[0015] 3 is an explanatory diagram showing an example of the relationship between the current lead angle θi, the torque command Tm*, and the electromagnetic forcing forces Fem of the electrical 6mth and 2nth orders. This relationship differs depending on the specifications of the motor 22, etc. The example in FIG. 3 illustrates a case where the torque command Tm* is a torque Tm1. The value θi1 is set to the current lead angle θi at the intersection of the torque Tm1 and the current lead angle optimum line, and the value θi2 is set, for example, to a value smaller than the value θi1 so that the effective current value Ir for the torque Tm1 is larger than the value θi1.

[0016] In the example of FIG. 3 , the electromagnetic forcing force of the electrical 6mth order decreases and then increases as the current advance angle θi increases, and the electromagnetic forcing force of the electrical 2nth order decreases as the current advance angle θi increases. Based on this, the value θi3 is set smaller than the value θi2 so that the electromagnetic forcing force Fem of the electrical 6mth order relative to the torque Tm1 is reduced while the effective current Ir remains constant or increases (the amount of heat generated by the motor 22 and inverter 24) compared to the value θi2. The value θi4 is set larger than the value θi2 so that the electromagnetic forcing force Fem of the electrical 2nth order relative to the torque Tm1 is reduced while the effective current Ir remains constant or increases compared to the value θi2. The value θi5 is set closer to the value θi1 compared to the values ​​θi3 and θi4 so that noise and vibration of the motor 22 are suppressed even if the effective current Ir relative to the torque Tm1 is slightly smaller than the values ​​θi3 and θi4.

[0017] In the drive device mounted on the electric vehicle 10 of the embodiment described above, when the temperature rise condition for the battery 26 is met and the NV problem condition is met, if the rotation speed Nm of the motor 22 is within a first rotation speed range in which motor noise and vibration become a problem due to electromagnetic forcing forces of the electrical 6mth order, the current advance angle θi is set to achieve both a reduction in the electromagnetic forcing force of the electrical 6mth order and an increase in the amount of heat generated by the motor 22 and the inverter 24. If the rotation speed Nm of the motor 22 is within a second rotation speed range in which motor noise and vibration become a problem due to electromagnetic forcing forces of the electrical 2nth order, the current advance angle θi is set to achieve both a reduction in the electromagnetic forcing force of the electrical 2nth order and an increase in the amount of heat generated by the motor 22 and the inverter 24. This makes it possible to raise the temperature of the power storage device while suppressing an increase in noise and vibration generated by the motor 22, depending on whether the electromagnetic forcing force of the electrical 6mth order or the electromagnetic forcing force of the electrical 2nth order is the problem.

[0018] In the above-described embodiment, the condition under which motor noise and vibration due to an electromagnetic forcing force of the electrical 6mth order becomes an issue is the rotation speed condition under which the rotation speed Nm of the motor 22 is within the first rotation speed range. However, it is also possible to use an AND condition consisting of the rotation speed condition and the torque condition under which the torque command Tm* is equal to or less than the threshold value Tmref. This is because when the torque of the motor 22 is relatively large, the degree of deterioration of noise and vibration of the motor 22 becomes smaller than when the torque is small. The same can be considered for the condition under which motor noise and vibration due to an electromagnetic forcing force of the electrical 2nth order becomes an issue.

[0019] In the above-described embodiment, the drive unit is mounted on an electric vehicle 10 equipped with a motor 22, but is not limited to this. For example, the drive unit may be mounted on a hybrid vehicle equipped with an engine in addition to a motor, or on a fuel cell vehicle equipped with a fuel cell in addition to a motor. The drive unit may also be mounted on a moving object other than a vehicle or on stationary construction equipment.

[0020] The correspondence between the main elements of the embodiment and the main elements of the invention described in the "Means for Solving the Problem" section will be described below. In the embodiment, the battery 26 corresponds to the "electricity storage device," the motor 22 corresponds to the "motor," the inverter 24 corresponds to the "inverter," the cooling device 40 corresponds to the "heat transfer device," and the ECU 50 corresponds to the "control device."

[0021] The correspondence between the main elements of the embodiments and the main elements of the invention described in the "Means for Solving the Problem" section does not limit the elements of the invention described in the "Means for Solving the Problem" section, since the embodiments are examples for specifically explaining the mode for implementing the invention described in the "Means for Solving the Problem" section. In other words, the interpretation of the invention described in the "Means for Solving the Problem" section should be based on the description in that section, and the embodiments are merely specific examples of the invention described in the "Means for Solving the Problem" section.

[0022] The above describes the forms for implementing the present disclosure using embodiments, but the present disclosure is not limited to these embodiments in any way, and it goes without saying that the present disclosure can be implemented in various forms within the scope that does not deviate from the gist of the present disclosure. [Industrial Applicability]

[0023] The present disclosure is applicable to industries such as the drive device manufacturing industry. [Explanation of symbols]

[0024] 22 Motor, 24 Inverter, 26 Battery, 40 Cooling device (heat transfer device), 50 ECU (control device).

Claims

[Claim 1] A drive device including: a power storage device; a motor; an inverter provided between the power storage device and the motor; a heat transfer device that transfers heat from the motor and / or the inverter to the power storage device; and a control device that controls the inverter using a current advance angle based on a torque command of the motor, When a temperature rise condition for the power storage device is met, if the rotation speed of the motor is within a first range in which noise and vibration of the motor become an issue due to electromagnetic forcing forces of an electrical 6m (m = 1, 2, ...), the control device sets the current advance angle so as to achieve both a reduction in the electromagnetic forcing force of the electrical 6m and an increase in the amount of heat generated by the motor and the inverter, and if the rotation speed is within a second range in which noise and vibration of the motor become an issue due to electromagnetic forcing forces of an electrical 2n (n = 1, 2, ...), the control device sets the current advance angle so as to achieve both a reduction in the electromagnetic forcing force of the electrical 2n and an increase in the amount of heat generated by the motor and the inverter. Drive unit.

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