Driving apparatus for DC circuit breakers

摘要

A driving apparatus for a DC circuit breaker of reverse current insertion type. The driving apparatus includes a magnetic repulsive coil for instantaneously driving a movable electrode of a vacuum valve directly in an opening direction, and a first coil of capacitor energization type and a second coil for voltage tripping purposes as trip coils for an operating mechanism connected to the movable electrode through a contact spring whereby the magnetic repulsive coil and the first trip coil are respectively energized by capacitors in the case of tripping under faulty conditions and only the second trip coil is energized in the case of tripping under other conditions than faulty conditions. By thus providing the high-speed tripping first coil for the tripping under faulty conditions and the low-speed tripping second coil for the tripping under other conditions than faulty conditions separately to be independent of each other, a mechanical trip-free mechanism is provided thus minimizing the opening stroke due to the magnetic repulsive coil, increasing the life of the vacuum valve and the operating mechanism and enhancing the reliability of the driving apparatus.