Abstract：Epoxy resin used as insulating material in radioactive environment is subjected to a great risk of surface discharge which may finally lead to damage of the material and cause catastrophic failure to the electrical equipment. Surface trap distribution plays a key role in determining the propagation process of surface discharge, and from the viewpoint of safety, it is essential to gain a firm understanding of radiation effect on surface trap distribution. In this paper, the effect of gamma-ray irradiation on surface trap characteristics of epoxy resin was examined by means of isothermal surface potential decay measurement. The sample was previously irradiated in air up to 100kGy and then up to 1 000kGy with dosage rate of 10kGy/h by using a 60Co gamma-source. Surface potential was established with dc corona charging through needle-grid-plate electrode system. The potential was monitored with an electrostatic voltmeter, by which surface trap density as well as surface trap depth could be calculated. Obtained results show that with the increase of the total irradiation dose the trap density decreases initially then tends to increase, while the trap depth appears to decrease. It is proposed that surface trap distribution is dependent upon chemical structure of surface layer, which is varied by radiation induced cross-linking and degradation reactions in epoxy resin.
高宇, 李莹, 崔劲达, 杜伯学. 伽玛线辐射对环氧树脂表面陷阱分布的影响[J]. 电工技术学报, 2012, 27(12): 264-269.
Gao Yu, Li Ying, Cui Jinda, Du Boxue. Effect of Gamma-Ray Irradiation on Surface Trap Distribution of Epoxy Resin. Transactions of China Electrotechnical Society, 2012, 27(12): 264-269.
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