1. State Key Laboratory of ASIC & System, School of Microelectronics, Fudan University, Shanghai, China
2. Department of Electrical and Electronic Engineering, University of Nottingham, Nottingham, U.K.
3. Power Electronics, Machine and Control Group, University of Nottingham, Nottingham, U.K.
4. Center of Ultra-Precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin, China