1. College of Engineering, Hebei Normal University, Shijiazhuang 050024, China
2. Hebei Provincial Innovation Center for Wireless Sensor Network Data Application Technology, Shijiazhuang 050024, China
3. Jiangsu Tailong Reducer Co., Ltd., Taizhou 225400, China
4. The Provincial Collaborative Innovation Center of Industrial Energy-Saving and Power Quality Control, Anhui University, Hefei 230601, China