1. College of Electrical and Information Engineering, Hunan University,Changsha,China
2. College of Electrical and Information Engineering, Hunan University,Changsha,China,410082
3. College of Electrical and Information Engineering of Hunan University,Changsha,China
4. Hunan University,Changsha,China
5. CSEE Journal of Power and Energy Systems, Chinese Journal of Electrical Engineering,China