To reduce a back electromotive force by quickly lowering the rotation of an electric motor while further properly protecting an inverter at the occurrence of a collision.

When a motor MG1 rotates at the prescribed number of revolutions or higher after the collision is detected by a hybrid ECU, there is executed three-phase on-control which turns on either or all of upper arm transistors T11 to T13 and lower arm transistors T14 to T16 of the inverter 41. Then, during the execution of the three-phase on-control, the turning-on/off of the upper arm transistors T11 to T13 and the turning-on/off of the lower arm transistors T14 to T16 are switched at each prescribed time.