Research on state assessment method of subway 35kv switchgear based on multi-feature quantities

The health status of 35kv switchgear directly affects the safe operation of subway. In view of the current problems of single feature quantity, inadequate detection elements and inaccurate overall state evaluation of switch gear, a state evaluation method for metro 35kv switch gear based on multi-feature quantity was proposed. The characteristic parameters such as transient ground voltage, ultrasonic value, cable joint temperature and bus temperature were determined by triangular fuzzy number method with constant weight. The variable weight method was introduced to ensure the balance of state evaluation, and the state evaluation of switch cabinet was carried out with matter-element extenics. The actual detection data of 35kv switchgear 8DA10 in a Shanghai metro substation is taken as an example to verify the effectiveness of the algorithm.