Design and Analysis of a Free-wheeling type DC Solid State Circuit Breaker for Data Center Applications

Abstract

With the increasing demand of low-voltage DC architectures in microgrids, electric mobility, and aerospace systems, fast and reliable short-circuit protection has become essential. Conventional mechanical breakers have slow response time, leading to high current stress and system over sizing. Solid-state circuit breakers (SSCBs) enable microsecond-scale current interruption; however, the release of energy stored in parasitic and line inductances produces high overvoltage transients that can damage semiconductors. Here the combination of freewheel-ing diode and resistance arrangement is used to mitigate excess energy during fault.This paper presents a detailed analysis of fault clearing transient of SSCB taking into account the effect of the line inductance, parasitic capacitances of the MOSFETs, and the freewheeling resistance and gives the value of freewheeling resistance used for a particular DC system