Methodical Identification and Evaluation of Critical Failures in DC Hybrid Switchgear

DC Hybrid switchgear are a key element for the safe operation of future high-efficient DC distribution systems. This paper contributes to improve the design of these switchgear in the course of future development processes. For this purpose, a proprietary failure analysis method based on an FMEA is presented and applied to a generic parallel structure of a hybrid DC switchgear as an example. Altogether more than 60 failure modes are identified and evaluated. The failure modes determined as particularly critical affect the function of opening of the hybrid switchgear and are discussed in detail. An examination of the causes, effects, detection approaches and possible mitigation measures of these failure modes are provided. This provides information on increasing the reliability and safety of hybrid switchgear as a basis for the design and development process.