Breaking performance of a circuit breaker influenced by a permanent magnetic field at DC voltages up to 450 V

Circuit breakers have been equipped with external permanent magnets to investigate their breaking behavior at DC voltage. The breaking operations were conducted at voltages up to 450 VDC and prospective currents from 10 A to 5000 A. The time constants 0 ms, 1 ms and 3 ms were adjusted. In comparison, breaking operations without permanent magnet were conducted to analyze the influence of the permanent magnetic field. Additionally, the arcing behavior was observed with a high-speed camera.