Simultaneous switching suppression device

PROBLEM TO BE SOLVED: To solve the problem with switching, wherein the time for delaying the switching of a switching state becomes longer beyond necessity, when avoiding the simultaneous switching of switching states of a plurality of switching elements. SOLUTION: An operation signal Upi of a U-phase power switching element indicates a switching command to an off-state, thereby inhibiting an output of a switching command of a switching state of another-phase power switching element over a prescribed period ΔT1 of time after the timing when the U-phase switching element indicates the switching command. Over a prescribed period ΔT2 of time with an elapse of a delay time Td after the switching command to the off-state, switching to an on-state of another phase is inhibited. By this arrangement, a switching command to an on-state of a W-phase operation signal Wpi is corrected to the end timing of the prescribed period ΔT2 of time. COPYRIGHT: (C)2011,JPO&INPIT