1. Department of Electrical and Electronic Engineering, The Hong Kong Polytechnic University, Hong Kong
2. School of Automation, Chongqing University, Chongqing, China
3. Center for More-Electric-Aircraft Power System of Ministry of Industry and Information Technology, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
4. College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China