JP7035609B2 - Drive - Google Patents

Description

The present invention relates to a drive device, and more particularly to a drive device including a motor, an inverter, first and second current sensors, and a control device.

Conventionally, as a drive device of this type, current measurement is performed in a drive device including a motor, an inverter for driving the motor, and first and second current sensors arranged in the U phase and the V phase of the motor, respectively. An abnormality (failure) of any of the first and second current sensors is detected by comparing the current measured values by the first and second current sensors in each of the U phase and the V phase, which are the phases, and at the time of abnormality detection. A method has been proposed in which an inverter is controlled so that a circulating current flows through the current measurement phase to identify an abnormal current sensor (see, for example, Patent Document 1). In this drive, such control enhances the reliability of current detection and allows the inverter to be controlled using the remaining normal current sensors.

Japanese Unexamined Patent Publication No. 2005-160136

In the above-mentioned drive device, since the inverter is controlled so that the circulating current flows through the current measurement phase at the time of abnormality detection to identify the abnormal current sensor, it is necessary to temporarily stop the drive of the drive device at the time of abnormality detection. However, when such an abnormality is detected, it may be desired to continue driving the drive device.

The main object of the drive device of the present invention is to continue driving the drive device when an abnormality occurs in the first and second current sensors of each phase.

The drive device of the present invention has adopted the following means in order to achieve the above-mentioned main object.

The drive device of the present invention is
With the motor
The inverter that drives the motor and
The first and second current sensors provided in each of the three phases of the motor, and
A control device that controls the inverter by using the phase currents from the first current sensor of at least two phases of the first current sensor of each phase.
It is a drive device equipped with
The control device has a total anomaly based on the total of the phase currents from the first current sensor of the three phases or the total of the phase currents from the second current sensor of the three phases, and the first current of each of the phases. Of the first current sensor of each phase and the second current sensor of each phase, the deviation anomaly based on the deviation between the phase current from the sensor and the corresponding phase current from the second current sensor is used. Detects any abnormality and
When an abnormality of at least one of the first current sensors of each phase is detected, the phase current used for controlling the inverter is calculated from the phase current from the first current sensor to the second current sensor. Switch to phase current from
The gist is that.

In the drive device of the present invention, the total anomaly based on the total phase current from the three-phase first current sensor or the total phase current from the three-phase second current sensor, and the first current sensor of each phase. With a deviation anomaly based on the deviation between the phase current from and the corresponding phase current from the second current sensor, an anomaly in either the first current sensor of each phase or the second current sensor of each phase. Is detected. Therefore, it is possible to detect an abnormality of either the first current sensor of each phase or the second current sensor of each phase while continuing to drive the drive device. Then, when an abnormality of at least one of the first current sensors of each phase is detected, the phase current used for controlling the inverter is changed from the phase current from the first current sensor to the phase from the second current sensor. Switch to current. As a result, the driving of the driving device can be continued.

In such a drive device of the present invention, the control device uses the sum anomaly based on the sum of the phase currents from the first current sensor of the three phases and the deviation anomaly, and uses the first current sensor of each phase. The abnormality of the second current sensor of each phase is detected by using the total abnormality based on the total of the phase currents from the second current sensor of the three phases and the deviation abnormality. May be good. In this way, it is possible to detect an abnormality in the first and second current sensors of each phase. In this case, when the control device detects an abnormality in the second current sensor of at least one of the first current sensors of each phase, the phase current used for controlling the inverter is transmitted from the first current sensor. The phase current from the first current sensor may be used without switching from the phase current of the above to the phase current from the second current sensor.

It is a block diagram which shows the outline of the structure of the electric vehicle 20 which mounts the drive device as one Example of this invention. It is a functional block diagram which shows the functional block of an electronic control unit 50. It is a flowchart which shows an example of the determination routine executed by the abnormality detection unit 53 of the electronic control unit 50 of an Example. It is explanatory drawing which shows an example of the relationship between the abnormality determination result in the determination routine, the setting of the phase currents Iu, Iv, Iw by the input switching unit 51, and the traveling mode. When an abnormality occurs in the phase current Iva from the main current sensor 32va, the phase currents Iva, Ivb, flags F1, F2, and the AchVW phase abnormality determination result, the BchVW phase abnormality determination result, and the phase currents Iv, Iw are set. It is a timing chart which shows an example of time change of a phase current (phase current Iv, Iw setting phase). It is a flowchart which shows an example of the control routine including the determination routine of the modification example.

Next, an embodiment for carrying out the present invention will be described with reference to examples.

FIG. 1 is a configuration diagram showing an outline of the configuration of an electric vehicle 20 equipped with a drive device as an embodiment of the present invention. As shown in the figure, the electric vehicle 20 of the embodiment includes a motor 32, an inverter 34, a battery 36 as a power storage device, and an electronic control unit 50.

The motor 32 is configured as a synchronous motor generator, and includes a rotor in which a permanent magnet is embedded and a stator in which a three-phase coil is wound. The motor 32 is connected to a drive shaft 26 in which a rotor is connected to the drive wheels 22a and 22b via a differential gear 24. A rotation position detection sensor 32a for detecting the rotation position of the rotor of the motor 32 is attached to the rotor of the motor 32. Further, a main current sensor 32ua and a sub-current sensor 32ub are attached to the U phase of the motor 32, and a main current sensor 32va and a sub-current sensor 32vb are attached to the V phase of the motor 32. A main current sensor 32wa and a sub-current sensor 32wb are attached to the W phase of the above.

The inverter 34 is used to drive the motor 32 and is connected to the battery 36 via the power line 38. The inverter 34 has transistors T11 to T16 as six switching elements, and six diodes D11 to D16 connected in parallel to each of the six transistors T11 to T16. Two transistors T11 to T16 are arranged in pairs so as to be on the source side and the sink side with respect to the positive electrode side line and the negative electrode side line of the power line 38, respectively. Further, each phase (U phase, V phase, W phase) of the motor 32 is connected to the connection point between the transistors paired with the transistors T11 to T16. Therefore, when a voltage is applied to the inverter 34, the electronic control unit 50 adjusts the ratio of the on-time of the paired transistors T11 to T16 to form a rotating magnetic field in the three-phase coil and the motor. 32 is rotationally driven.

The battery 36 is configured as, for example, a lithium ion secondary battery or a nickel hydrogen secondary battery. As described above, the battery 36 is connected to the inverter 34 via the power line 38.

The electronic control unit 50 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, and an input / output port in addition to the CPU. Signals from various sensors are input to the electronic control unit 50 via the input port. The signals input to the electronic control unit 50 include, for example, the rotation position θm from the rotation position detection sensor 32a, the U-phase phase currents Iua, Iub of the motor 32 from the main current sensor 32ua and the sub-current sensor 32ub, and the main. Examples include the V-phase phase currents Iva, Ivb of the motor 32 from the current sensor 32va and the sub-current sensor 32vb, and the W-phase phase currents Iwa, Iwb of the motor 32 from the main current sensor 32wa and the sub-current sensor 32wb. Further, the voltage Vb of the battery 36 from a voltage sensor (not shown) attached between the terminals of the battery 36 and the current Ib of the battery 36 from a current sensor (not shown) attached to the output terminal of the battery 36 can also be mentioned. Further, the ignition signal from the ignition switch 60 and the shift position SP from the shift position sensor 62 that detects the operation position of the shift lever 61 can also be mentioned. In addition, the accelerator opening Acc from the accelerator pedal position sensor 64 that detects the amount of depression of the accelerator pedal 63, the brake pedal position BP from the brake pedal position sensor 66 that detects the amount of depression of the brake pedal 65, and the vehicle speed sensor 68. The vehicle speed V can also be mentioned. From the electronic control unit 50, a switching control signal or the like to the transistors T11 to T16 of the inverter 34 is output via the output port. The electronic control unit 50 calculates the electric angle θe and the rotation number Nm of the motor 32 based on the rotation position θm of the rotor of the motor 32 from the rotation position detection sensor 32a.

In the electric vehicle 20 of the embodiment configured in this way, the required torque Td * required for the drive shaft 26 is set based on the accelerator opening degree Acc and the vehicle speed V, and the required torque Td * is set as the torque command Tm * of the motor 32. Is set to, and switching control of the transistors T11 to T16 of the inverter 34 is performed by pulse width modulation control (PWM control) so that the motor 32 is driven by the torque command Tm *.

Next, the operation of the electric vehicle 20 of the embodiment, particularly the control of the inverter 34 will be described. FIG. 2 is a functional block diagram showing a functional block of the electronic control unit 50. In FIG. 2, the signals input to the electronic control unit 50 from the rotation position detection sensor 32a, the main current sensor 32ua, the sub-current sensor 32ub, the main current sensor 32va, and the sub-current sensor 32vb are shown for ease of viewing. Was omitted. As shown in FIG. 2, the electronic control unit 50 includes an input switching unit 51, a motor control unit 52, and an abnormality detection unit 53 as functional blocks.

The input switching unit 51 includes the U-phase phase currents Iua and Iub of the motor 32 from the main current sensor 32ua and the sub-current sensor 32ub, and the V-phase phase current of the motor 32 from the main current sensor 32va and the sub-current sensor 32vb. The phase currents Iwa and Iwb of the W phase of the motor 32 from the Iva and Ivb, the main current sensor 32wa and the sub-current sensor 32wb are input. The input switching unit 51 determines whether or not an abnormality has occurred in the information from the abnormality detection unit 53 (main current sensor 32ua, sub-current sensor 32ub, main current sensor 32va, sub-current sensor 32vb, main current sensor 32wa, sub-current sensor 32wb). Based on the determination result), the phase current Iva or the phase current Ivb is set for the phase current Iv of the V phase, the phase current Iwa or the phase current Iwb is set for the phase current Iw of the W phase, and the phase current of the U phase is set. Set Iu to a value obtained by subtracting the sum of the phase current Iva and the phase current Iwa from the value 0 or a value obtained by subtracting the sum of the phase current Ivb and the phase current Iwb from the value 0, and set the phase currents Iu, Iv, Iw. Is output to the motor control unit 52.

The motor control unit 52 of the transistors T11 to T16 is based on the phase currents Iu, Iv, Iw of each phase from the input switching unit 51 and the rotation position θm of the rotor of the motor 32 from the rotation position detection sensor 32a. A PWM signal is generated and output to the transistors T11 to T16. Specifically, it is as follows. Using the electric angle θe of the motor 32, the U-phase and V-phase phase currents Iu, Iv, and Iw are coordinate-converted to the d-axis and q-axis currents Id and Iq (3-phase-2 phase conversion). Further, the current commands Id * and Iq * of the d-axis and the q-axis are set based on the torque command Tm * of the motor 32 based on the accelerator opening degree Acc and the vehicle speed V. Subsequently, the d-axis and q-axis voltage commands Vd * and Vq * are set by the equations (1) and (2) using the d-axis and q-axis current commands Id * and Iq * and the currents Id and Iq. .. Here, equations (1) and (2) are relational expressions in current feedback control for canceling the difference between the current commands Id * and Iq * on the d-axis and q-axis and the currents Id and Iq. Yes, in the equations (1) and (2), "kd1" and "kq1" are gains of proportional terms, and "kd2" and "kq2" are gains of integral terms. Then, using the electric angle θe of the motor 32, the voltage commands Vd * and Vq * on the d-axis and q-axis are coordinate-converted to the voltage commands Vu *, Vv * and Vw * of each phase (2-phase-3 phase conversion). By comparing the voltage commands Vu *, Vv *, Vw * of each phase with the carrier, the PWM signals of the transistors T11 to T16 are generated and output to the transistors T11 to T16. By such control, the vehicle can be driven while driving the motor 32 with the torque command Tm *.

Vd * = kd1 × (Id * －Id) ＋ kd2 × ∫ (Id * －Id) dt (1)
Vq * = kq1 × (Iq * －Iq) ＋ kq2 × ∫ (Iq * －Iq) dt (2)

The abnormality detection unit 53 includes the U-phase phase currents Iua and Iub of the motor 32 from the main current sensor 32ua and the sub-current sensor 32ub, and the V-phase phase current of the motor 32 from the main current sensor 32va and the sub-current sensor 32vb. The phase currents Iwa, Iwb of the W phase of the motor 32 from the Iva, Ivb, the main current sensor 32wa, and the sub-current sensor 32wb are input. Then, the abnormality detection unit 53 uses the phase currents Iua, Iva, Iwa, Iub, Ivb, and Iwb of each phase to cause an abnormality in the main current sensors 32ua, 32va, 32wa, and the sub-current sensors 32ub, 32vb, 32wb. It is determined whether or not it is present, and this determination result is output to the input switching unit 51. The determination of this abnormality will be described later.

When the abnormality detection unit 53 inputs information that the main current sensors 32ua, 32va, 32wa and the sub-current sensors 32ub, vb, 32wb have no abnormality, the input switching unit 51 inputs the phase current of the V phase. Set the phase current Iva to Iv, set the phase current Iwa to the W phase phase current Iw, and set the U phase phase current Iu to the value obtained by subtracting the sum of the phase current Iva and the phase current Iwa from the value 0. , The set phase currents Iu, Iv, Iw are output to the motor control unit 52. The motor control unit 52 of the transistors T11 to T16 is based on the phase currents Iu, Iv, Iw of each phase from the input switching unit 51 and the rotation position θm of the rotor of the motor 32 from the rotation position detection sensor 32a. A PWM signal is generated and output to the transistors T11 to T16. In this way, when there is no abnormality in the main current sensors 32ua, 32va, 32wa and the sub-current sensors 32ub, vb, 32wb, the phase currents Iu, Iv, Iw are set from the phase currents Iva, Iwa, and the set phase currents are set. It travels in the normal traveling mode in which the motor 32 is driven by the torque command Tm * using Iu, Iv, and Iw.

Next, the operation of the electric vehicle 20 of the embodiment configured in this way, particularly the operation when an abnormality of the main current sensors 32ua, 32va, 32wa and the sub-current sensors 32ub, 32vb, 32wb is detected will be described. First, the process of determining whether or not an abnormality has occurred in the main current sensors 32ua, 32va, 32wa and the sub-current sensors 32ub, 32vb, 32wb will be described, and then the operation when the abnormality is detected will be described.

FIG. 3 is a flowchart showing an example of a determination routine executed by the abnormality detection unit 53 of the electronic control unit 50 of the embodiment. This routine is executed repeatedly. When this routine is executed, the abnormality detection unit 53 of the electronic control unit 50 has phase currents Iua, Iva, Iwa, Iub of each phase from the main current sensors 32ua, 32va, 32wa, and the sub-current sensors 32ub, 32vb, 32wb. The process of inputting Ivb and Iwb is executed (step S100).

Subsequently, it is determined whether or not the sum of the phase currents Iua, Iva, and Iwa is 0 (step S110). In this determination, even when the sum of the phase currents Iua, Iva, and Iwa is different from the value 0 but is close to the value 0, it is determined that the sum of the phase currents Iua, Iva, and Iwa is the value 0. When any of the main current sensors 32ua, 32va, and 32wa has an abnormality, the sum of the phase currents Iua, Iva, and Iwa does not become a value of 0. Hereinafter, an abnormality in which the total of the three-phase currents does not have a value of 0 may be referred to as a “total anomaly”.

When the sum of the phase currents Iua, Iva, and Iwa is 0 in step S110, it is determined that the main current sensors 32ua, 32va, and 32wa are normal, and the process proceeds to step S160.

When the sum of the phase currents Iua, Iva, and Iwa is not 0 in step S110, it is determined that a sum abnormality has occurred, that is, an abnormality has occurred in any of the main current sensors 32ua, 32va, and 32wa. Subsequently, it is determined whether or not the phase current Iva and the phase current Ivb are equal and the phase current Iwa and the phase current Iwb are equal (step S120). In this determination, when the deviation between the phase current Iva and the phase current Ivb is small and it can be determined that the phase current Iva and the phase current Ivb are equal, it is determined that the phase current Iva and the phase current Ivb are equal. do. Similarly, when the deviations of the phase current Iwa and the phase current Iwb are small and it is safe to determine that the phase current Iwa and the phase current Iwb are equal, it is determined that the phase current Iwa and the phase current Iwb are equal. do. When an abnormality occurs in any of the main current sensors 32va and 32wa, the deviation between the phase current Iva and the phase current Ivb or the deviation between the phase current Iwa and the phase current Iwb does not become a value of 0. Hereinafter, such an abnormality in which the deviation of the corresponding phase current does not have a value of 0 may be referred to as a “deviation abnormality”.

In step S120, when the phase current Iva and the phase current Ivb are equal and the phase current Iwa and the phase current Iwb are equal, it is determined that the main current sensors 32va and 32wa are normal, and the process proceeds to step S140.

In step S120, when the phase current Iva and the phase current Ivb are not equal to each other, or the phase current Iwa and the phase current Iwb are not equal to each other, it is determined that one of the main current sensors 32va and 32wa has an abnormality ( Step S130), the process proceeds to step S140. Hereinafter, the occurrence of an abnormality in any of the main current sensors 32va and 32wa may be referred to as "an abnormality has occurred in the AchVW phase".

When it is determined in this way whether or not an abnormality has occurred in any of the main current sensors 32va and 32wa, it is subsequently determined whether or not the phase current Iua and the phase current Iub are equal (step S140). In this determination, as in the determination in step S120, when the difference between the phase current Iua and the phase current Iub is a slight difference and it can be determined that the phase current Iua and the phase current Iub are equal, the phase current Iua And the phase current Iub are determined to be equal.

When the phase current Iua and the phase current Iub are equal in step S140, the main current sensor 32ua is determined to be normal, and the process proceeds to step S160.

When the phase current Iua and the phase current Iub are not equal in step S140, it is determined that an abnormality has occurred in the main current sensor 32ua (step S150), and the process proceeds to step S160. Hereinafter, the occurrence of an abnormality in the main current sensor 32ua may be referred to as “an abnormality has occurred in the AchU phase”.

After determining whether or not the main current sensor 32ua has an abnormality in this way, it is subsequently determined whether or not the sum of the phase currents Iub, Ivb, and Iwb is 0 (step S160). In this determination, it is determined that the sum of the phase currents Iub, Ivb, and Iwb is 0 even when the sum of the phase currents Iub, Ivb, and Iwb is different from the value 0 but is close to the value 0.

When the sum of the phase currents Iub, Ivb, and Iwb is 0 in step S110, it is determined that the sub-current sensors 32ub, 32vb, 32wb are normal, and this routine is terminated.

When the sum of the phase currents Iub, Ivb, and Iwb is not 0 in step S160, it is determined that an abnormality has occurred in any of the sub-current sensors 32ub, 32vb, and 32wb, and then the same processing as in step S120 is performed. Then, it is determined whether or not the phase current Iva and the phase current Ivb are equal and the phase current Iwa and the phase current Iwb are equal (step S170).

In step S170, when the phase current Iva and the phase current Ivb are equal and the phase current Iwa and the phase current Iwb are equal, it is determined that the sub-current sensors 32vb and 32wb are normal, and the process proceeds to step S190.

In step S120, when the phase current Iva and the phase current Ivb are not equal to each other, or when the phase current Iwa and the phase current Iwb are not equal to each other, it is determined that an abnormality has occurred in the sub-current sensors 32vb and 32wb (step S180). , Step S190. Hereinafter, the occurrence of an abnormality in any of the sub-current sensors 32vb and 32wb may be referred to as "an abnormality has occurred in the BchVW phase".

When it is determined in this way whether or not an abnormality has occurred in the sub-current sensors 32vb and 32wb, it is subsequently determined whether or not the phase current Iua and the phase current Iub are equal by the same processing as in step S140 (step S190). ..

When the phase current Iua and the phase current Iub are equal in step S190, it is determined that the sub-current sensor 32ub is normal, and this routine is terminated.

When the phase current Iua and the phase current Iub are not equal in step S190, it is determined that an abnormality has occurred in the sub-current sensor 32ub (step S200), and this routine is terminated. Hereinafter, the occurrence of an abnormality in the sub-current sensor 32ub may be referred to as “an abnormality has occurred in the BchU phase”. By such processing, it is determined whether or not an abnormality has occurred in any of the main current sensor 32va and 32wa and the sub-current sensor 32vb and 32wb, and whether or not an abnormality has occurred in the main current sensor 32ua and the sub-current sensor ub. be able to.

Next, the operation when any abnormality of the main current sensors 32ua, 32va, 32wa and the sub-current sensors 32ub, 32vb, 32wb is detected will be described. FIG. 4 is an explanatory diagram showing an example of the relationship between the abnormality determination result in the above-mentioned determination routine, the setting of the phase currents Iu, Iv, and Iw by the input switching unit 51, and the traveling mode.

When it is determined that an abnormality has occurred in the AchU phase, BchVW phase, or BchU phase in steps S150, S180, and S200 of the determination routine, the phase currents Iu, using the phase currents Iva and Iwa from the main current sensors 32va and 32wa, Iv and Iw may be set. Therefore, the input switching unit 51 sets the phase currents Iu, Iv, Iw using the phase currents Iva, Iwa, and the motor control unit 52 sets the phase currents Iu, Iv, Iw of each phase from the input switching unit 51. , The inverter 34 (transistors T11 to T16) is controlled by the PWM signal based on the rotation position θm of the rotor of the motor 32 from the rotation position detection sensor 32a. As a result, it is possible to travel in the normal traveling mode.

When the AchVW phase is abnormal in step S130 of the determination routine, the phase currents Iu, Iv, Iw are set by using the phase currents Iva, Iwa from the main current sensors 32va, 32wa in the input switching unit 51, and the motor control unit 52. In the PWM signal based on the phase currents Iu, Iv, Iw of each phase from the input switching unit 51 and the rotation position θm of the rotor of the motor 32 from the rotation position detection sensor 32a, the inverter 34 (transistors T11 to T16). If is controlled, the inverter 34 (transistors T11 to T16) cannot be properly controlled. Therefore, the input switching unit 51 sets the phase currents Iu, Iv, Iw using the phase currents Ivb, Iwb from the sub-current sensors 32vb, 32wb, and the motor control unit 52 sets the phase currents Iu, Iv, Iw of each phase from the input switching unit 51. The inverter 34 (transistors T11 to T16) is controlled by a PWM signal based on the phase currents Iu, Iv, Iw and the rotation position θm of the rotor of the motor 32 from the rotation position detection sensor 32a. In this way, it is possible to travel in the retracted travel (Bch travel) mode by controlling using the phase currents Ivb and Iwb from the sub-current sensors 32vb and 32wb.

When a plurality of abnormalities among the AchU phase abnormality, the BchVW phase abnormality, the BchU phase abnormality, and the AchVW phase abnormality occur, the vehicle is stopped.

FIG. 5 shows an abnormality determination result of the phase currents Iva, Ivb, flags F1, F2, and AchVW phase, an abnormality determination result of the BchVW phase, and a phase current Iv, when an abnormality occurs in the phase current Iva from the main current sensor 32va. It is a timing chart which shows an example of the time change of the phase current (phase current Iv, Iw setting phase) set in Iw. The flag F1 is a flag that becomes a value 1 when the sum of the phase currents Iva, Iwa, and Iua is 0, and becomes a value 0 when the sum is not a value 0. The flag F2 is a flag having a value of 1 when the phase current Iva and the phase current Ivb are equal, and a value 0 when the phase current Iva and the phase current Ivb are not equal. When an abnormality occurs in the main current sensor 32va (time t1), the phase currents Iva, Iwa, Iua, Ivb, Iwb, and Iub of each phase are detected by the main current sensors 32ua, 32va, 32wa, and the sub-current sensors 32ub, 32vb, 32wb. Flags F1 and F2 become value 0 with a delay of time (time t2). After that, it is determined that the AchVW phase is abnormal in the process of step S130 of the determination routine described above, and the phase currents Iv and Iw setting phases are switched from the phase currents Iva and Iwa to the phase currents Ivb and Iwb (time t3). By such processing, when an abnormality occurs in any of the main current sensors 32va and 32wa, the running of the vehicle (driving of the motor 32) can be continued.

According to the electric vehicle 20 of the embodiment described above, the total anomaly based on the total of the phase currents Iua, Iva, and Iwa from the main current sensors 32ua, 32va, and 32wa, and the phase current Iua, the phase current Iub, and the phase current Iva. Using the phase current Ivb, the deviation abnormality based on the deviation between the phase current Iwa and the phase current Iwb, any abnormality of the main current sensor 32ua, 32va, 32wa, or the sub-current sensor 32ub, 32vb, 32wb is detected, and the main When an abnormality in one of the current sensors 32va and 32wa is detected, the phase currents Iu, Iv and Iw used for controlling the inverter 34 are used as the phase currents Iva and Iwa from the main current sensors 32va and 32wa, and the sub current sensors 32vb and 32wb are used. By switching to the phase currents Ivb and Iwb from, the running of the vehicle (driving of the motor 32) can be continued.

In the electric vehicle 20 of the embodiment, the input switching unit 51 sets the phase current Iu of the U phase to the value obtained by subtracting the sum of the phase current Iva and the phase current Iwa from the value 0 or the value 0 to the phase current Ivb and the phase current Iwb. The value obtained by subtracting the sum of is set. However, the phase current Iu from the main current sensor 32ua or the phase current Iub from the sub-current sensor ub may be set to the phase current Iu of the U phase. In this case, the abnormality detection unit 53 replaces the setting of the phase currents Iu, Iv, Iw and the traveling mode by the determination routine illustrated in FIG. 3 and the input switching unit 51 exemplified in FIG. The control routine including the determination routine of the modification example illustrated in 1 may be executed. In the control routine of the modification of FIG. 6, for the sake of explanation, control based on whether or not there is an abnormality in the W phase main current sensor 32wa and the sub current sensor 32wb is illustrated, but the same control is performed in the U phase. It is applied to the control based on whether or not an abnormality has occurred in the main current sensor 32ua and the sub-current sensor 32ub, and the control based on whether or not an abnormality has occurred in the V-phase main current sensor 32va and the sub-current sensor 32vb.

The control routine of the modified example of FIG. 6 is executed by the electronic control unit 50 (input switching unit 51, abnormality detection unit 53, motor control unit 52). First, in the same process as step S100 of the determination routine of FIG. 3, the phase currents Iua, Iva, Iwa, Iub, Ivb of each phase from the main current sensors 32ua, 32va, 32wa, and the sub-current sensors 32ub, 32vb, 32wb, Iwb is input (step S300).

Subsequently, it is determined whether or not the traveling mode is the evacuation traveling mode (step S310). Examples of the evacuation running mode include a running mode different from the normal running mode due to an Ach running mode or some other abnormality, in addition to the Bch running mode described above. The Ach driving mode will be described later.

When it is determined in step S310 that the traveling mode is not the retracting traveling mode, it is determined whether or not the phase current Iwa and the phase current Iwb are equal by the same processing as in step S140 of the determination routine of FIG. 3 (step S320). ). When the phase current Iwa and the phase current Iwb are equal, it is determined that no abnormality has occurred in the main current sensor 32wa, and the inverter 34 is controlled to run in the normal running mode (step S330), and the process of step S300 is performed. Return to. In this case, in the normal driving mode, the phase currents Iua, Iva, and Iwa are set to the phase currents Iu, Iv, and Iw, and the set phase currents Iu, Iv, and Iw are used to drive the motor 32 with the torque command Tm *. Run.

When the phase current Iwa and the phase current Iwb are not equal in step S320, it is determined that an abnormality has occurred in either the main current sensor 32wa or the sub-current sensor 32wb, and subsequently, step S110 of the determination routine of FIG. In the same process as above, it is determined whether or not the total sum of the phase currents Iua, Iva, and Iwa is 0 (step S340). When the sum of the phase currents Iua, Iva, and Iwa is 0, it is determined that an abnormality has occurred in the sub-current sensor 32wb and the phase current Iwb is an abnormal value (step S350), and the retracted running mode (Ach running mode) is determined. ), The inverter 34 is controlled (step S360), and this routine is terminated. In the retracted running mode (Ach running mode), the phase currents Iua, Iva, and Iwa are set to the phase currents Iu, Iv, and Iw, and the set phase currents Iu, Iv, and Iw are used to drive the motor 32 with the torque command Tm *. And run. Therefore, in the embodiment, the evacuation running mode (Ach running mode) is the same running mode as the normal running mode.

When the sum of the phase currents Iua, Iva, and Iwa is not 0 in step S340, it is determined that an abnormality has occurred in the main current sensor 32wa and the phase current Iwa is an abnormal value (step S370), and the retracted running mode (Bch) is determined. The inverter 34 is controlled to run according to the running mode) (step S380), and this routine is terminated. By such control, when an abnormality occurs in the main current sensor 32wa used for controlling the inverter 34 in the normal traveling mode, the traveling of the vehicle can be continued.

When the evacuation travel mode is determined in step S310, it is determined whether or not the evacuation travel mode is the evacuation travel mode (Ach travel mode) due to the phase current Iwb being an abnormal value (step S390). It is determined whether or not the evacuation travel mode is the evacuation travel mode (Bch travel mode) due to the phase current Iwa being an abnormal value (step S400).

When the evacuation running mode is neither the evacuation running mode (Ach running mode) nor the evacuation running mode (Bch running mode) in steps S390 and S400, it is determined that the evacuation running mode is different from the Ach running mode and the Bch running mode. Then, the running in the evacuation running mode is continued (step S410), and this routine is terminated. By such a process, the traveling in the evacuation traveling mode can be continued.

In steps S390 and S400, when the evacuation drive mode is not the evacuation drive mode (Ach drive mode) but is the evacuation drive mode (Bch drive mode), that is, the sub-current sensor 32wb is normal and the main current sensor 32wa is abnormal. When it occurs, it is determined whether or not the sum of the phase currents Iub, Ivb, and Iwb is 0 (step S420). When the sum of the phase currents Iub, Ivb, and Iwb is 0, it is determined that the sub-current sensors 32ub, 32vb, 32wb are normal, and the traveling in the retracted traveling mode (Bch traveling mode) is continued (step S430). ), End this routine. By such a process, the traveling in the evacuation traveling mode (Bch traveling mode) can be continued.

When the sum of the phase currents Iub, Ivb, and Iwb is not 0 in step S420, it is determined that the sub-current sensor 32wb is normal but one of the sub-current sensors 32ub, 32vb has an abnormality, and the vehicle is moved. Stop (step S440) and end this routine. When an abnormality has occurred in the main current sensor 32wa and an abnormality has occurred in any of the sub-current sensors 32ub and 32vb, the inverter 34 cannot be properly controlled. Therefore, the vehicle can be stopped in such a case. ..

In step S390, when the evacuation travel mode is evacuation travel (Ach travel) due to an abnormal value of the phase current Iwb, that is, when the main current sensor 32wa is normal and the sub-current sensor 32wb has an abnormality, the phase current It is determined whether or not the sum of Iua, Iva, and Iwa has a value of 0 (step S450). When the sum of the phase currents Iua, Iva, and Iwa is 0, it is determined that the main current sensors 32ua, 32va, and 32wa are normal, and the traveling in the retracted traveling mode (Ach traveling mode) is continued (step S460). ), End this routine. By such processing, the traveling in the evacuation traveling mode (Ach traveling mode) can be continued.

When the sum of the phase currents Iua, Iva, and Iwa is not 0 in step S450, it is determined that the main current sensor 32wa is normal but one of the main current sensors 32ua, 32va is abnormal, and the vehicle is moved. Stop (step S470) and end this routine. When an abnormality has occurred in the sub-current sensor 32wb and an abnormality has occurred in any of the main current sensors 32ua and 32va, the inverter 34 cannot be properly controlled. Therefore, the vehicle can be stopped in such a case. ..

By such control, the motor 32 is driven to continue running the vehicle unless an abnormality occurs in at least one of the main current sensors 32ua, 32va, 32wa and at least one of the sub-current sensors 32ub, 32vb, 32wb. Can be made to.

In the drive device mounted on the electric vehicle 20 of the embodiment, the battery 36 is used as the power storage device, but a capacitor may be used instead of the battery 36.

The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the motor 32 corresponds to the "motor", the inverter 34 corresponds to the "inverter", the main current sensors 32ua, 32va, 32wa correspond to the "first current sensor", and the sub-current sensors 32ub, 32vb, 32wb corresponds to the "second current sensor", and the electronic control unit 50 corresponds to the "control device".

As for the correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem, the invention described in the column of means for solving the problems of the examples is carried out. Since it is an example for specifically explaining the mode for solving the problem, the elements of the invention described in the column of means for solving the problem are not limited. That is, the interpretation of the invention described in the column of means for solving the problem should be performed based on the description in the column, and the examples are the inventions described in the column of means for solving the problem. It is just a concrete example.

Although the embodiments for carrying out the present invention have been described above with reference to the embodiments, the present invention is not limited to these embodiments and may be in various embodiments within the scope of the gist of the present invention. Of course it can be done.

The present invention can be used in the driving device manufacturing industry and the like.

20 electric vehicle, 22a, 22b drive wheel, 24 differential gear, 26 drive shaft, 32 motor, 32a rotation position detection sensor, 32ua, 32va, 32wa main current sensor, 32ub, 32vb, 32wb sub-current sensor, 34 inverter, 36 battery , 38 power line, 50 electronic control unit, 51 input switching unit, 52 motor control unit, 53 abnormality detection unit, 60 ignition switch, 61 shift lever, 62 shift position sensor, 63 accelerator pedal, 64 accelerator pedal position sensor, 65 brake Pedal, 66 brake pedal position sensor, 68 vehicle speed sensor, D11 to D16 diodes, T11 to T16 transistors.

Claims (1)

With the motor
The inverter that drives the motor and
The first and second current sensors provided in each of the three phases of the motor, and
A control device that controls the inverter by using the phase currents from the first current sensor of at least two phases of the first current sensor of each phase.
It is a drive device equipped with
The control device has a total abnormality based on the total of the phase currents from the first and second current sensors of the three phases, the phase current from the first current sensor of each phase, and the second current sensor. Using the deviation anomaly based on the deviation from the corresponding phase current, anomalies in either the first current sensor of each phase or the second current sensor of each phase are detected.
When an abnormality of at least one of the first current sensors of each phase is detected, the phase current used for controlling the inverter is calculated from the phase current from the first current sensor to the second current sensor. Switch to phase current from
Drive device.

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