Self-Powered and Self-Controlled Hybrid DC Circuit Breaker for Low Voltage Applications

Current research and development on DC circuit breakers (DCCB) are on (i) mechanical (ii) solid state and (iii) hybrid. Each type has its own advantages and disadvantages. In the case of solid-state or hybrid DCCBs where semiconductor switches are utilised, additional circuitry are required such as voltage and current sensors, gate drivers and power supplies to drive and control the semiconductor switches. This digest presents a hybrid circuit breaker which has the capability to drive the semiconductor switches on its own without having any additional DC power supplies or gate drivers. Validation of the circuit was done through experimental results. The experimental work has resulted in a 2 ms disconnection with negligible arc for a 100 A current in a DC loop with a 60 V DC power source, compared to a commercially available mechanical breaker with an approximate 3.25 ms break time with a severe arc.