Circuit and control strategy optimization of solid-state power controller for all-electric system

Abstract

Solid-state power controller (SSPC) have been received increasing attention as it is vital to ensure the reliability and safety in All-electric System (AES). However, the traditional SSPC is easy to misjudge the high instantaneous current generated when capacitive or inductive load is started as load short circuit, activate tripping protection and cause misprotection. It also does not have the ability to suppress large current under short-circuit conditions. The short-circuit current may exceed the safe working range of MOSFET or generate high heat, resulting in damage to MOSFET. Therefore, this paper proposes a new SSPC circuit and control strategy to prevent false tripping protection caused by high instantaneous current and protect the device from thermal damage. In addition, this paper establishes three circuit models of capacitive load, motor and short circuit, carries out simulation analysis, and compares the traditional SSPC with the improved SSPC. The experimental results show that the method in this paper suppresses the large instantaneous current to 10A or the set value within tens of microseconds of instantaneous start-up, while the traditional method will have a steep peak and false protection. Finally, by summarizing the research results, a new anti time curve suitable for airborne equipment distribution control system is proposed.