1. National Engineering Laboratory for Electric Vehicles, Beijing Institute of Technology, Beijing, China
2. Department of Electrical Sustainable Energy, Delft University of Technology, Delft, CD, The Netherlands
3. School of Electromechanical Engineering, Beijing Information Science and Technology University, Beijing, China
4. Department of Mathematics, The University of Manchester, Manchester, U.K.
5. Zhejiang Geely Automobile Research Institute Company, Ltd., Ningbo, China