| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for controlling commutation wherein voltage applied to a semiconductor switching element is remarkably reduced and the breakdown voltage of the semiconductor switching element and the like can be reduced to half the conventional one or lower, and also provide a current type power converter using this method. SOLUTION: In a method for controlling commutation wherein commutation is conducted by controlling the ON/OFF of a plurality of semiconductor switching elements 3-8, a means 19, 20 for repeating a plurality of times a switching operation of moving an ON state from one semiconductor switching element 3 to another element 4 at the set intervals (T1+T2, T3+T4,...) is installed. This current-type power inverter uses the same method for controlling commutation as the above. Due to this structure, an output phase-to-phase voltage peak of the inverter caused by resonance at the load side during commutation is remarkably reduced when commutation is controlled in multiple stages. Therefore, the voltage applied to the semiconductor switching elements 3-8 is also reduced remarkably. By this method, the breakdown voltage of a single semiconductor switching element used can be reduced to half the conventional one or lower. |
