A Novel Bidirectional Low-Loss Solid-State Circuit Breaker for More Electric Aircraft HVDC Power Supply System

HVDC power supply system has become the preferred power supply scheme for more electric aircraft (MEA) because of its high efficiency, low weight, and excellent output power quality. The Z-source solid-state circuit breaker (ZSCB) holds a unique position in airborne HVDC power supply systems, especially when it comes to isolating short-circuit faults. To improve some defects of the existing ZSCBs, such as high on-state loss, reflecting fault current to the source, and lack of hot start function, a novel ZSCB topology based on two-winding coupled inductors is proposed in this paper. The novel ZSCB is characterized by bidirectional power flow in the steady state and forced commutation under the short-circuit state due to the anti-parallel thyristor structure and the magnetic coupling effect of the coupled inductor. Firstly, the topological structure of the novel ZSCB is described. Subsequently, a comprehensive analysis of the operating principle of the novel ZSCB is conducted.-Finally, the effectiveness of the novel structure was confirmed through simulation results obtained from Saber.