[1] Provincial and Ministerial Co-construction Collaborative Innovation Center on Reliability Technology of Electrical Products, Hebei University of Technology, Tianjin,300401, China
[2] Zouping Power Supply Company, State Grid Shandong Electric Power Company, Shandong, Zouping,256200, China
[3] Handan New Area Power Supply Company, State Grid Hebei Electric Power Company, Hebei, Handan,056000, China
[4] Zhangjiakou Power Supply Company, State Grid Jibei Electric Power Company, Hebei, Zhangjiakou,075000, China