| 摘要 |
PROBLEM TO BE SOLVED: To reduce losses due to a semiconductor switch provided to isolate a power converter, when a load is frequently and repeatedly started and stopped during driving of the load by the converter. SOLUTION: A unipolar semiconductor element is used as a semiconductor switch and the building-up voltage of a parasitic diode is set to a value higher than the on-voltage of the unipolar semiconductor element. Thus unipolar characteristics are provided bidirectionally, and the losses produced in the switch can be reduced. The switch is placed on the direct-current side and alternating- current side of the power converter. |
