1. Henan STAR Electric Power Equipment Co., Ltd., Xuchang,461500, China; 2. School of Electrical Engineering, Xi'an Jiaotong University, Xi'an,710049, China; 3. State Grid Shaanxi Electric Power Company Electric Power Research Institute, Xi’an 710048, China; 4. China Electric Power Research Institute, Wuhan 430074, China
TM86