[1] China Elect Power Res Inst, Nanjing 210000, Jiangsu, Peoples R China
[2] Nanjing Univ Posts & Telecommun, Nanjing 210000, Jiangsu, Peoples R China
[3] State Grid Jiangsu Elect Power Co, Nanjing 210000, Jiangsu, Peoples R China
[4] China Elect Power Res Inst, Nanjing 210000, Jiangsu, Peoples R China