1. State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering (SEEE), Huazhong University of Science and Technology (HUST), Wuhan, China
2. Physikalisch-Technische Bundesanstalt, Brunswick, Germany
3. China Electric Power Research Institute, Wuhan, China
4. School of Electrical and Electronic Engineering (SEEE), Huazhong University of Science and Technology (HUST), Wuhan, China