1. Xi'an Jiaotong University,Stare Key Laboratory of Electrical Insulation and Power Equipment,Xi'an,China
2. The Shandong Power Equipment CO. LTD,Jinan,China
3. Hefei University of Technology, School of Electrical Engineering and Automation,Hefei,China
4. Electric Power Research Institute, State Grid Anhui Electric Power Company Ltd.,Hefei,China