ISSN 2196-5625 CN 32-1884/TK
1. College of Energy and Electrical Engineering, Hohai University, Nanjing 210098, China 2. Department of Electronic, Electrical and Computer Engineering, University of Birmingham, Birmingham B15 2TT, UK
This work was supported by National Natural Science Foundation of China (No. 51422701). The authors would also like to thank the support of Chinese National ‘‘111’’ Project of ‘‘Renewable Energy and Smart Grid’’ at Hohai University.