1. College of Energy and Power Engineering, Changsha University of Science & Technology, Changsha 410114, P. R. China
2. Hubei Key Laboratory of Power System Design and Test for Electrical Vehicle, Hubei University of Arts and Science, Xiangyang 441053, P. R. China
3. School of Electric Engineering, Shanghai Dianji University, Shanghai 201306, P. R. China
4. State Key Laboratory of Industrial Control Technology, Institute of Industrial Process Control, College of Control Science and Engineering, Zhejiang University, Hangzhou 310058, P. R. China
5. State Grid Hunan Extra High Voltage Substation Company, Changsha 410029, P. R. China
6. Substation Intelligent Operation and Inspection, Laboratory of State Grid Hunan Electric Power, Co., Ltd., Changsha 410029, P. R. China