1. School of Electrical Engineering and Automation and the National Engineering Laboratory of Energy-Saving Motor and Control Technology, Anhui University, Hefei, China
2. School of Electrical Engineering and Automation, Anhui University, Hefei, China
3. The School of Electrical Engineering and Automation, National Engineering Laboratory of Energy-Saving Motor and Control Technology, and the Anhui Collaborative Innovation Center of Industrial Energy-Saving and Power Quality Control, Anhui University, Hefei, China