Abstract: An electric power conversion apparatus is provided which can protect the electric power conversion circuit against an overcurrent even when the interrupting circuit for preventing an inflow of an overcurrent into the input side caused by phase deviations between an input voltage and an output voltage uses switching means with a slow responsiveness. The switching means used in the interrupting circuit 2 have a slower response speed than those of semiconductor switching elements. The overcurrent detection circuit 3 checks whether the input current is an overcurrent. For as long as an overcurrent is detected by the overcurrent detection circuit 3, the command input blocking circuit 4 blocks the instantaneous current control signal and the instantaneous voltage control signals from being fed into the drive signal generation circuit 5. As the duration of overcurrent increases, the interrupting circuit 2 is activated to interrupt the current inflow.

Abstract: An electric power conversion apparatus is provided which can protect the electric power conversion circuit against an overcurrent even when the interrupting circuit for preventing an inflow of an overcurrent into the input side caused by phase deviations between an input voltage and an output voltage uses switching means with a slow responsiveness. The switching means used in the interrupting circuit 2 have a slower response speed than those of semiconductor switching elements. The overcurrent detection circuit 3 checks whether the input current is an overcurrent. For as long as an overcurrent is detected by the overcurrent detection circuit 3, the command input blocking circuit 4 blocks the instantaneous current control signal and the instantaneous voltage control signals from being fed into the drive signal generation circuit 5. As the duration of overcurrent increases, the interrupting circuit 2 is activated to interrupt the current inflow.