1. Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu 610039, China
2. Key Laboratory of Automotive Measurement, Control and Safety, Sichuan Province, Xihua University, Chengdu 610039, China
3. National Traction Power Laboratory, Southwest Jiaotong University, Chengdu 610031, China
4. School of Technology, Xihua University, Chengdu 610039, China
5. Institute of Information Research, Southwest Jiaotong University, Chengdu 610031, China