1. State Grid Shandong Electric Power Corporation Weifang Power Supply Company,Weifang,China
2. State Grid Shandong Electric Power Corporation Changyi Power Supply Company,Changyi,China
3. State Grid Shandong Electric Power Corporation Changle Power Supply Company,Changle,China
4. Shandong Kehua Electric Power Technology CO. LTD.,Jinan,China
5. College of Electrical engineering, Qingdao University,Qingdao,China