Patent ID: 9608431
Date: 2017-03-28
CPC Classifications: H02G,H02H,H02J,Y02E

Claim:
1. A method for interrupting a DC current flowing in an AC high voltage circuit breaker comprising the steps of: providing said AC high voltage circuit breaker comprising a first interrupter and a second interrupter, said first interrupter capable of passing said DC current for a period of time and said second interrupter capable of passing a cancellation current for another period of time, and a making switch; opening said first interrupter causing said DC current to flow through a first interrupter arc as a first contact of said first interrupter moves away from a second contact of said first interrupter causing a gap between said first contact of said first interrupter and said second contact of said first interrupter; closing said making switch to cause said cancellation current to flow through said making switch, said second interrupter and said first interrupter arc in a direction opposite to said DC current; arc quenching said DC current flowing in said AC high voltage circuit breaker as said gap between said first contact of said first interrupter and said second contact of said first interrupter approaches a maximum gap distance and as a sum of said DC current and said cancellation current in said first interrupter passes through zero; and arc quenching said sum of said DC current and said cancellation current in said second interrupter about when a value of said cancellation current reaches or passes through zero.