DC circuit breaker unit for high voltage systems - having circuit breaker, oscillator and metal oxide varistor in parallel

摘要

D.c. circuit breaker equipment has a circuit breaker, an oscillator circuit contg. a capacitor and a coil, a switch, which connects the circuit breaker in parallel with the oscillator circuit when this is opened, and a resistor for charging the capacitor. The novelty is that a varistor (RN) contg. a sintered metal oxide mixt. is connected in parallel to the oscillator circuit. This pref. consists of ZnO, MgO, CoO, NiO, Sb2O3 or Bi2O3. The circuit breaker is suitable for d.c. transmission systems of high voltage and large capacity. The construction is simple and the circuit can be broken rapidly.