1. School of Electrical and Electronic Engineering, Shandong University of Technology , Zibo , 255000 , Shandong Province , China
2. State Grid Shandong Electric Power Company Zibo Power Supply Company , Zibo , 255000 , Shandong Province , China
3. School of New Energy, Harbin Institute of Technology , Weihai , 264209 , Shandong , China