1. State Key Laboratory of Power System, Department of Electrical Engineering, Tsinghua University, Beijing, China
2. School of Mechanical and Electrical Engineering, China University of Mining and Technology-Beijing, Beijing, China
3. School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore
4. Faculty of Engineering, Universidad San Sebastian, Santiago, Chile
5. Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada