School of Electrical Engineering Dalian University of Technology Dalian 116024 China;
School of Electrical Engineering Dalian University of Technology Dalian 116024 China;
School of Electrical Engineering Dalian University of Technology Dalian 116024 China;
School of Electrical Engineering Dalian University of Technology Dalian 116024 China;
School of Electrical Engineering Dalian University of Technology Dalian 116024 China;
Dalian Electric Power Supply Company Dalian 116000 China;
School of Electrical Engineering Dalian University of Technology Dalian 116024 China;