1. Shandong University,Shandong Provincial Key Laboratory of UHV Transmission Technology and Equipment,Jinan,China
2. Qingdao Power Supply Company, State Grid Shandong Electric Power Company,Qingdao,China
3. Mechanical and Electrical Business Department of Tongyuan Design Group Co., Ltd,Jinan,China
4. North China Electric Power University,State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,Beijing,China