Abstract: DC systems are an important technical direction that supports a high proportion of new energy access and flexible and efficient energy use. Solid state DC circuit breaker has the advantages of extremely fast breaking speed, simple structure, and service life, and is widely used in medium and low voltage DC systems. With the development of power electronic devices, the topology and working performance of solid-state DC circuit breakers are also constantly improving. Based on the reverse blocking intergrated gate commutated thyristor(IGCT), this paper proposes a new type of solid-state DC circuit breaker structure: the main branch adopts the reverse blocking IGCT anti-parallel structure to realize bidirectional flow. The snubber branch adopts the MOV-C structure to suppress overvoltage and AC harmonics wave. At the same time, the parameter design method of key components is given and verified, a gravity heat pipe radiator with 700 W heat dissipation power is designed, and a control strategy is proposed to improve the reliability of the circuit breaker. Finally, a 750 V/2 kA solid-state DC circuit breaker prototype is developed and passes the long-term test and breaking test with 10 kA maximum turn-off current. It has the advantages of low cost, small size, high reliability and good application prospects.