Series type hybrid circuit breaker with non-resonant current zero-crossing generation

Abstract

A series-type hybrid circuit breaker to provide protection against short circuit faults in DC or AC power circuits. A series-type hybrid circuit breaker (SHCB) forces a fault current into a high-frequency AC current with zero crossings and allows a mechanical circuit breaker to disconnect the faulty branch. The SHCB injects a transient counter voltage pulse via a pulse transformer into the main power loop upon detection of an overcurrent condition and forces the fault current to change its original direction and cross zero to a negative peak value. A generation power electronic circuit on the primary side of the transformer controls the discharge of a capacitor to generate the counter voltage pulse during the first phase of each switching cycle of the fault interruption process. The power electronic circuit then changes the polarity of the injected secondary voltage and forces the fault current to change direction and cross zero again.

Dependencies are inferred from the claim text.