[1] State Grid Zhejiang Elect Power Co, Jiaxing Power Supply Co, Jiaxing 314000, Peoples R China
[2] Zhejiang Univ, Coll Elect & Engn, Hangzhou 310027, Peoples R China
[3] State Grid Zhejiang Elect Power Co Ltd, Hangzhou 310000, Peoples R China
[4] State Grid Econ & Technol Res Inst Co Ltd, Beijing 102209, Peoples R China