1. Guangxi Key Laboratory of Power System Optimization and Energy Technology, Guangxi University, Nanning, China
2. School of Electrical Engineering, Chongqing University, Chongqing, China
3. CHINT Electric Company Ltd., Shanghai, China
4. Guangxi Power Grid Company Ltd., China Southern Power Grid, Nanning, China
5. Guangxi Liuzhou Special Transformer Company Ltd., Liuzhou, China
6. Xian XD Transformer Company Ltd., Xian, China