[1] China Elect Power Res Inst, Beijing, Peoples R China
[2] Wuhan Univ, Sch Elect Engn, Wuhan, Hubei, Peoples R China
[3] China Southern Power Grid, Dept Training Ctr, Guangzhou, Guangdong, Peoples R China
[4] Nanyang Technol Univ, Sch Elect & Elect Engn, Singapore, Singapore