| 摘要 |
PROBLEM TO BE SOLVED: To simplify a circuit configuration of a power converter and reduce electric stress applied to a main switching element for power conversion. SOLUTION: In this power converter, the increase in the collector to emitter voltage of each IGBT(insulated gate bipolar transistor) 8-13 for power conversion is suppressed by charging of each capacitor 33-38 when each IGBT 8-13 is turned off and therefore each IGBT 8-13 is turned off at zero voltage. When each IGBT 8-13 is turned on, current is caused to flow in each main diode 14-19 through reactors 39, 40, 41 for commutation, a commutation bridge circuit 57, and an IGBT 64 for commutation by switching operation of the IGBT 64, and therefore each IGBT 8-13 is turned on at zero voltage and zero current. Accordingly, electric stress applied to each IGBT 8-13 can be reduced by a simple circuit configuration. |
