1. Xuefeng Mountain Energy Equipment Safety National Observation and Research Station of Chongqing University, Chongqing 400044, China
2. Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
3. Department of Mechanical Engineering, North China Electric Power University, Baoding 071066, China
4. Electric Power Research Institute, China Southern Power Grid Corporation, Guangzhou 510630, China
5. State Key Laboratory of Disaster Prevention & Reduction for Power Grid Transmission and Distribution Equipment, State Grid Corporation of China, Changsha 410023, China