| 摘要 |
PROBLEM TO BE SOLVED: To perform cost reduction and labor saving of maintenance, and to prevent overcharge of a smoothing capacitor as well, by providing a DC circuit-breaker between a DC power supplying point and a DC reactor, and providing a semiconductor circuit-breaker between DC reactor and the positive terminal of the smoothing capacitor. SOLUTION: Between a DC power source 1 and an inverter 5 which receives DC power from the DC power source 1 and performs DC-AC conversion, an electric circuit composed of a DC circuit-breaker 2 which interrupts a current mechanically, a DC reactor 3, a semiconductor circuit-breaker 10, and a smoothing capacitor 4 connected in the order is interposed. Here, the semiconductor circuit-breaker 10 is used for suppressing an inrush current on the occasion of charging the smoothing capacitor 4 by the DC power source 1, and it interrupts a direct current flowing in the DC reactor 3. Consequently, it becomes possible to perform cost reduction and labor saving of maintenance. Besides, it becomes possible to prevent overcharge of the smoothing capacitor caused by the energy of the DC reactor generated by a transient phenomenon. |
