7KimJeongho, Song Woochang, Lee Jaehyung, et al. Leakage current monitoring and outdoor degradation of silicone rubber [J]. IEEE Transactions on Dielectrics and ElectricalInsulation, 2001, 8(6): 1108-1115.
8Suda T. Frequency characteristics of leakage current waveforms of a string of suspension insulators[J]. IEEE Transactions on Power Delivery, 2005, 20(1): 481-487.
9Chisholm W A, Buchan P G, Jary T. Accurate measurement of low insulator contamination levels[J]. IEEE Transactions on Power Delivery, 1994, 9(3): 1552-1557.
10Viteli M. Temperature distribution along outdoor insulator subjected to differ-rent pollution levels[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2000, 7 (3):416-423.