Analysis of Short Circuit Protection Failure and Component Defect of Low Voltage Switchgear

Low voltage switchgear is the main short circuit protection equipment in low voltage distribution networks. When key internal components fail to work, the short circuit fault current can not be broken, posing a threat to the safety of power equipment and system. The working principle of low voltage switchgear protection devices are analyzed, the reasons for non breaking of short circuit current and arc extinguishing failure of switchgear are analyzed, the distribution of component defects of key components are obtained, and the process and hazards of failure of key components are analyzed by combining test waveforms and physical images in the paper. It also proposes some methods for conducting short circuit withstand strength testing of key components after conducting component function pre testing, and some product performance optimal design methods.