1State Key Laboratory of Electrical Insulation and Power Equipment , Xi'an Jiaotong University , Xi'an , Shaanxi , China ; Communication and Information Engineering College, Xi'an University of Science and Technology , Xi'an , Shaanxi , China
2[State Key Laboratory of Electrical Insulation & Power Equipment, Xi'an Jiaotong University, Xi'an, Shaanxi, China]
3State Key Laboratory of Electrical Insulation and Power Equipment , Xi'an Jiaotong University , Xi'an , Shaanxi , China ; Divisions of Electricity and Magnetism , National Institute of Metrology , Beijing , China
