AC/AC DIRECT CONVERSION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a simple sequence commutating circuit, to reduce a surge voltage and noise generated at the terminal of a load, whereby to obtain desired control performance, to lower cost, and to reduce a device in size. SOLUTION: In the AC/AC direct conversion device, each of AC switches is constituted of at least two unidirectional switches that can control unidirectional currents, the AC switches are connected between terminals of input and output sides, respectively, and a multi-phase AC voltage at a power supply side is converted into a multi-phase AC voltage having an arbitrary magnitude and frequency. The AC/AC direct conversion device comprises a means 4 that determines the relation of the magnitude of each phase power supply voltage, a means 3 that determines the unidirectional switch to which a reverse voltage is applied from voltage command pulses S1*, S2* and S3* of each phase AC switch generated in accordance with the relation of the magnitude determined by the means 4, and a gate-on command and changeover switch 6 or the like that constantly turns on the switches. COPYRIGHT: (C)2005,JPO&NCIPI