1. School of Electrical and Power Engineering, China University of Mining and Technology, No. 1 Daxue Road, Xuzhou 221116, China
2. Key Laboratory of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education, School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
3. State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China