1. High voltage Institute China Electric Power Research Institute,Beijing,China
2. State Grid Ningxia Electric Power Co.,Ltd,Equipment management department,Ningxia,China
3. State Grid Ningxia Electric Power Co.,Ltd,Science and technology department,Ningxia,China
4. Maintenance Filiale of State Grid Ningxia Power Co. State Grid Ningxia Electric Power Co.,Ltd,Ningxia,China