1. School of Electrical & Information Engineering, Changsha University of Science & Technology 1 , Changsha 410114, China
2. School of Energy and Power Engineering, Changsha University of Science & Technology 2 , Changsha 410114, China
3. Zhuzhou CRRC Times Semiconductor Co., Ltd. 3 , Zhuzhou 412000, China
4. School of Automation, Central South University 4 , Changsha 410083, China