1. School of Mechanical Engineering and Automation, Harbin Institute of Technology (Shenzhen), Shenzhen, China
2. Department of Mechanical and Electrical Engineering, Electrical Engineering Section, University of Southern Denmark, Odense, Denmark
3. Department of Electrical Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing, China
4. School of Electrical and Electronic Engineering, Nanyang Technological University, Jurong West, Singapore