1. School of Electronic and Information Engineering and the National Engineering Laboratory of Energy-Saving Motor and Control Technology, Anhui University, Hefei, China
2. Engineering Research Center of Power Quality, Ministry of Education, and the National Engineering Laboratory of Energy-Saving Motor and Control Technology, Anhui University, Hefei, China
3. National Engineering Laboratory of Energy-Saving Motor and Control Technology and the School of Electrical Engineering and Automation, Anhui University, Hefei, China
4. School of Ocean Information Engineering, Jimei University, Xiamen, China