1. Key Laboratory of the Ministry of Education on Smart Power Grids, School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, China
2. Tangshan Power Supply Company of State Grid Jibei Electric Power Co., Ltd., Tangshan 063099, China
3. Chengnan District Power Supply Company of State Grid Tianjin Electric Power Co., Ltd., Tianjin 300201, China
4. Electric Power Research Institute State Grid Xinjiang Co., Ltd., Urumqi 830063, China