[1] Harbin Inst Technol Shenzhen, Sch Mech Engn & Automat, Shenzhen 518000, Peoples R China
[2] Univ Southern Denmark, Dept Mech & Elect Engn, Elect Engn Sect, DK-5230 Odense, Denmark
[3] Tsinghua Univ, Dept Elect Engn, State Key Lab Power Syst, Beijing 100084, Peoples R China
[4] Nanyang Technol Univ, Sch Elect & Elect Engn, Singapore, Singapore