Comparative Analysis of Power Semiconductor Devices for Use as a Solid-State Circuit Breaker in a Cryogenically Cooled Electrical Aircraft Propulsion Network

The DC circuit breaker (DCCB) is a critical component in cryogenically cooled electrified aircraft propulsion (EAP), which needs to be operated under extremely low temperature condition for the reliable fault protection. As the device selection is the key factor to design a reliable DCCB, this study assesses the behaviour of semiconductor switches as DC interrupters to ensure the reliability and performance of solid-state circuit breakers (SSCBs) in steady-state and fault conditions. To achieve this, an experimental setup and a modular SSCB was designed to evaluate and compare commercial Si, SiC, and GaN field-effect transistors (FETs) for the temperature range of 300K to 77K. The study characterized the static and dynamic on-state resistance of the power devices and analyzed SSCB behaviour during fault condition. The experimental results show that GaN FET devices performance improved to maintain the fault current interruption process and energy absorption capabilities at 77K, enhancing their potential for improving SSCB design for cryogenic applications, while Si and SiC devices show degraded performance.