Power device with commonly used switching elements

摘要

A power device includes at least two power conversion circuits respectively having at least one of switching elements, at least one of which switching elements in these conversion circuits being used in common as an element constituting the at least two different power conversion circuits, a control device providing at least a period in which at least one of currents flowing from at least one of the different power conversion circuits to the commonly used switching element has a polarity inverse to at least the other one of the currents flowing from at least the other one of the power conversion circuits, so as to cancel each other, and a unit for detecting the state of the respective conversion circuits. The operation of the switching elements is thereby made modifiable in accordance with a lowering in the resistance of a load of the device, and the withstand voltage of the elements can be prevented effectively from rising even upon any fluctuation in the load.