[1] Tsinghua Univ, Shenzhen Int Grad Sch, Inst Adv Technol Power & Elect Engn, Shenzhen 518055, Peoples R China
[2] Yunnan Power Grid Co Ltd, Elect Power Res Inst, Kunming 650217, Yunnan, Peoples R China
[3] China Elect Power Res Inst, State Key Lab Power Grid Environm Protect, Wuhan 430074, Peoples R China