[1] Zhengzhou Univ, Sch Elect Engn, Zhengzhou 450001, Peoples R China
[2] Power China Huadong Engn Corp, Hangzhou 311122, Peoples R China
[3] Univ Sci & Technol China, State Key Lab Fire Sci, Hefei 230026, Peoples R China
[4] State Grid Jiangsu Elect Power Co Ltd, Res Inst, Nanjing 211103, Peoples R China