Comparative Evaluation of High Power Solid State Power Controller (SSPC) With and Without Auxiliary Over-current Bypass Circuit

Abstract

This paper explores the possibility of a semiconductor-based over-current bypass circuit for high current solid-state power controllers (SSPCs). Therefore, two different topologies of the bidirectional DC SSPCs: a. without over-current bypass circuit b. with an over-current bypass circuit are presented for the same power ratings. The first SSPC consists of a parallel matrix connection of the discrete MOSFET devices (conducts during nominal and over-current conditions) and the second one is designed with fewer MOSFET loops (conducts during nominal condition) and additional IGBT modules matrices to bypass the over-current. The thermal performances of both the SSPCs are evaluated analytically and compared during the nominal and over-current situations. Later, the PLECS simulation models of the SSPCs are developed and the junction temperature of the devices are estimated. The overall weight, power density, and cost of these two SSPCs are approximated for the comparison. It is found that the SSPC topology with bypass circuit exhibits better power density and lower cost. Therefore, it can be employed to replace the tradition circuit breakers for the more electric aircraft (MEA) in the near future.