[1] Shenzhen Univ, Guangdong Key Lab Electromagnet Control & Intellig, Natl Key Lab Green & Long Life Rd Engn Extreme Env, Shenzhen 518060, Peoples R China
[2] Tongji Univ, Natl Maglev Transportat Engn R&D Ctr, Shanghai 201804, Peoples R China
[3] Univ Tennessee, Dept Elect Engn & Comp Sci, Knoxville, TN 37996 USA