[1] Shenzhen Univ, Coll Mechatron & Control Engn, Shenzhen Key Lab Electromagnet Control, Shenzhen 518060, Peoples R China
[2] Hunan Univ, Coll Elect & Informat Engn, Changsha 410082, Hunan, Peoples R China
[3] Tech Univ Denmark, Dept Elect Engn, Ctr Elect Power & Energy, DK-2800 Lyngby, Denmark
[4] Univ Queensland, Sch Informat Technol & Elect Engn, Power & Energy Syst Grp, Brisbane, Qld 4072, Australia