Design of Thyristor DC Solid-state Circuit Breaker with Operating Duty Capability

DC grid has attracted a major interest due to the advent of renewable energy such as photovoltaic energy and wind power. For the safety and protection of the DC grid, the DC circuit breaker as fundamental component to the DC gird has received a lot of concern. A new thyristor DC solid-state circuit breaker (DC SSCB) is proposed in this paper. Its main advantage is to have the capability of naturally charging the commutation capacitor for stable and reliable interruption function. That is, the proposed DC SSCB have no need of additional switching operation for the purpose of charging the commutation capacitor. Moreover, the proposed DC SSCB can carry out the operating duty which performs the reclosing and rebreaking operation. The prototype of proposed SSCB is fabricated with the design specification of a rating of 5 [kW] and 380 [V], and its operating features are verified by the experimental results.