Control device for vehicle drive device

1. A control device for a vehicle drive device, a control target for the control device being the vehicle drive device including a rotating electrical machine, the control device comprising:

an actual rotational speed obtaining part that obtains an actual rotational speed, the actual rotational speed being an actual rotational speed of the rotating electrical machine;

an actual torque obtaining part that obtains actual torque, the actual torque being actual torque of the rotating electrical machine; and

a determining part that determines a state of the rotating electrical machine,

wherein

the determining part determines that the state of the rotating electrical machine is a negative torque abnormality, when the actual torque has a negative value smaller than a torque threshold value set based on a relationship between the actual rotational speed and target torque of the rotating electrical machine,

wherein the torque threshold value

decreases as the actual rotational speed increases when the actual rotational speed is positive, and

does not change depending on the actual rotational speed when the actual rotational speed is negative.

2. The control device for a vehicle drive device according to claim 1 , wherein the determining part performs rotating electrical machine stop control that stops the rotating electrical machine, when the determining part determines that the state of the rotating electrical machine is the negative torque abnormality.

3. The control device for a vehicle drive device according to claim 2 , wherein

the vehicle drive device further includes an inverter device that is connected to a direct-current power supply and connected to the rotating electrical machine to convert electric power between direct current of the direct-current power supply and multiphase alternating current of the rotating electrical machine,

the inverter device includes: a plurality of upper-stage-side switching elements connected to a positive polarity side of the direct-current power supply; and a plurality of lower-stage-side switching elements connected to a negative polarity side of the direct-current power supply, and

in the rotating electrical machine stop control,

at least one of

active short-circuit control that brings either all of the plurality of upper-stage-side switching elements or all of the plurality of lower-stage-side switching elements into an on state and brings other ones into an off state,

shutdown control that brings all of the plurality of upper-stage-side switching elements and the plurality of lower-stage-side switching elements into an off state, and

rotating electrical machine zero-torque control that controls the rotating electrical machine such that the actual torque reaches zero is performed.

4. The control device for a vehicle drive device according to claim 2 , further comprising: an input member drive-coupled to an internal combustion engine; an output member drive-coupled to wheels; an engagement device; and a transmission,

wherein

in a power transmission path connecting the input member to the output member, the engagement device, the rotating electrical machine, and the transmission are provided in this order from an internal combustion engine side, and

when the actual torque has a negative value smaller than the torque threshold value, the determining part performs, in addition to the rotating electrical machine stop control, at least one of engagement disengagement control that brings the engagement device into a disengaged state and neutral control that brings a state of the transmission into a neutral state in which drive power is not transmitted.

5. The control device for a vehicle drive device according to claim 4 , wherein when the determining part performs the engagement disengagement control, the determining part performs internal combustion engine zero-torque control that controls the internal combustion engine such that internal combustion engine actual torque reaches zero, the internal combustion engine actual torque being actual torque of the internal combustion engine.

6. The control device for a vehicle drive device according to claim 1 , wherein the torque threshold value

does not change depending on the target torque of the rotating electrical machine when the target torque is positive, and

decreases as the target torque of the rotating electrical machine decreases when the target torque is negative.

7. The control device for a vehicle drive device according to claim 1 , wherein the determining part does not determine a state of the rotating electrical machine when the actual rotational speed is greater than or equal to a specified rotational speed threshold value.

8. The control device for a vehicle drive device according to claim 2 , wherein the torque threshold value

decreases as the actual rotational speed increases when the actual rotational speed is positive, and

does not change depending on the actual rotational speed when the actual rotational speed is negative.

9. The control device for a vehicle drive device according to claim 2 , wherein the torque threshold value

does not change depending on the target torque of the rotating electrical machine when the target torque is positive, and

decreases as the target torque of the rotating electrical machine decreases when the target torque is negative.

10. The control device for a vehicle drive device according to claim 2 , wherein the determining part does not determine a state of the rotating electrical machine when the actual rotational speed is greater than or equal to a specified rotational speed threshold value.

11. The control device for a vehicle drive device according to claim 1 , wherein the torque threshold value

does not change depending on the target torque of the rotating electrical machine when the target torque is positive, and

decreases as the target torque of the rotating electrical machine decreases when the target torque is negative.

12. The control device for a vehicle drive device according to claim 1 , wherein the determining part does not determine a state of the rotating electrical machine when the actual rotational speed is greater than or equal to a specified rotational speed threshold value.

13. A control device for a vehicle drive device, a control target for the control device being the vehicle drive device including a rotating electrical machine, the control device comprising:

an actual rotational speed obtaining part that obtains an actual rotational speed, the actual rotational speed being an actual rotational speed of the rotating electrical machine;

an actual torque obtaining part that obtains actual torque, the actual torque being actual torque of the rotating electrical machine; and

a determining part that determines a state of the rotating electrical machine,

wherein

the determining part performs rotating electrical machine stop control that stops the rotating electrical machine, when the actual torque has a negative value smaller than a torque threshold value set based on a relationship between the actual rotational speed and target torque of the rotating electrical machine,

wherein the torque threshold value

decreases as the actual rotational speed increases when the actual rotational speed is positive, and

does not change depending on the actual rotational speed when the actual rotational speed is negative.

14. The control device for a vehicle drive device according to claim 13 , wherein

the vehicle drive device further includes an inverter device that is connected to a direct-current power supply and connected to the rotating electrical machine to convert electric power between direct current of the direct-current power supply and multiphase alternating current of the rotating electrical machine,

the inverter device includes: a plurality of upper-stage-side switching elements connected to a positive polarity side of the direct-current power supply; and a plurality of lower-stage-side switching elements connected to a negative polarity side of the direct-current power supply, and

in the rotating electrical machine stop control,

at least one of

active short-circuit control that brings either all of the plurality of upper-stage-side switching elements or all of the plurality of lower-stage-side switching elements into an on state and brings other ones into an off state,

shutdown control that brings all of the plurality of upper-stage-side switching elements and the plurality of lower-stage-side switching elements into an off state, and

rotating electrical machine zero-torque control that controls the rotating electrical machine such that the actual torque reaches zero is performed.

15. The control device for a vehicle drive device according to claim 13 , further comprising: an input member drive-coupled to an internal combustion engine; an output member drive-coupled to wheels; an engagement device; and a transmission,

wherein

in a power transmission path connecting the input member to the output member, the engagement device, the rotating electrical machine, and the transmission are provided in this order from an internal combustion engine side, and

when the actual torque has a negative value smaller than the torque threshold value, the determining part performs, in addition to the rotating electrical machine stop control, at least one of engagement disengagement control that brings the engagement device into a disengaged state and neutral control that brings a state of the transmission into a neutral state in which drive power is not transmitted.

16. The control device for a vehicle drive device according to claim 15 , wherein when the determining part performs the engagement disengagement control, the determining part performs internal combustion engine zero-torque control that controls the internal combustion engine such that internal combustion engine actual torque reaches zero, the internal combustion engine actual torque being actual torque of the internal combustion engine.

17. The control device for a vehicle drive device according to claim 13 , wherein the torque threshold value

does not change depending on the target torque of the rotating electrical machine when the target torque is positive, and

decreases as the target torque of the rotating electrical machine decreases when the target torque is negative.

18. The control device for a vehicle drive device according to claim 13 , wherein the determining part does not determine a state of the rotating electrical machine when the actual rotational speed is greater than or equal to a specified rotational speed threshold value.