1. North China Electric Power University,Hebei Key Laboratory of Electric Machinery Health Maintenance & Failure Prevention,Baoding,China
2. China Electric Power Research Institute,State Key Laboratory of Power Grid Environmental Protection,Wuhan,China
3. North China Electric Power University,School of Electrical and Electronic Engineering,Baoding,China
4. Electric Power Research Institute,State Grid Xin jiang Company Limited,Urumqi,China