1. School of Electrical Engineering, Anhui Polytechnic University,Wuhu,China
2. Wuhu Fanchang District Power Supply Company, State Grid Anhui Electric Power Co., Ltd,Wuhu,China
3. Wuwei City Power Supply Company, State Grid Anhui Electric Power Co., Ltd,Wuhu,China
4. School of Electrical Engineering, Anhui Polytechnic University, Anhui Institute of Future Technology,Wuhu,China