1. Department of Discover and Plan, State Grid Hengshui Electric Power Supply Company, Hengshui, China
2. Research Center of Economic and Technology, State Grid Hengshui Electric Power Supply Company, Hengshui, China
3. Department of Electronic Engineering, National Chin-Yi University of Technology, Taichung, Taiwan
4. Power Supply Service Command Center, Tianjin Chengxi District Power Supply Company, Tianjin, China
5. School of Electrical Engineering, Hebei University of Technology, Tianjin, China