[1] Sichuan Univ, Coll Elect Engn & Informat Technol, Chengdu 610065, Sichuan, Peoples R China
[2] State Grid Jinan Power Supply Co, Jinan 250012, Shandong, Peoples R China
[3] Chengdu Univ Informat Technol, Coll Control Engn, Chengdu 610225, Sichuan, Peoples R China
[4] Univ Tennessee, Dept Elect Engn & Comp Sci, Knoxville, TN 37996 USA