POWER CONVERSION DEVICE, ELECTRIC POWER STEERING SYSTEM, ELECTRIC VEHICLE, ELECTRONIC CONTROL THROTTLE, AND ELECTRIC BRAKE

摘要

A first object of the present invention is to provide high reliability, a long lifetime, miniaturization, and high speed protective operation of a unit for separating a phase in which a failure has occurred upon failure and for connecting a drive circuit to a motor terminal to be driven. For a semiconductor replaced from an unit for separating the phase in which the failure has occurred upon failure and for connecting the drive circuit to the motor terminal to be driven, a second object of the present invention is to provide interruption of output that causes regenerative braking to a motor even when any of phase output lines is short-circuited to the ground or short-circuited to a power source, in addition to a short fault of a MOSFET included in an inverter. In order to achieve the first object of the present invention, in a power conversion device according to the present invention, a semiconductor element is used as an unit that is connected to each phase and a neutral point of a four-phase motor or a three-phase motor and that separates the phase and connects a drive circuit to a motor terminal to be driven. In order to achieve the second object of the present invention, the semiconductor switching element included in the power conversion device according to the present invention is connected so that a diode connected in parallel with the semiconductor switching element is connected in a direction in which a current path is not formed between a power source and a ground and so that the diode is further connected in a direction in which a current path is formed neither between a winding of the motor and the power source nor between the winding of the motor and the ground.