【摘要】 针对直流GIL中的自由金属微粒污染物问题,研究表面覆膜措施对金属微粒启举的限制机理。利用气体电离及界面电荷积聚理论提出了直流应力下电极覆膜时金属微粒带电及启举模型,并根据微粒带电量的时变特征提出了充电时间的概念。为验证模型的正确性,构建了多功能模块的金属微粒带电.运动观测实验平台,对不同大小、材质的球形金属微粒以及不同厚度的PET薄膜开展实验,实验结果验证了模型的正确性:直流应力下,覆膜措施产生的界面极化过程只是增加了微粒的充电时间,而对微粒最终带电量并无影响,但覆膜产生的静电吸附力可显著提高微粒的启举电压;外施电压、覆膜介电常数及体电导率对微粒充电时间均有显著影响;而由于充电时间的存在使得电极覆膜措施下出现微粒"间歇启举"现象。更多还原

【Abstract】 To solve the problem of free metal-particles pollution in DC gas insulated metal enclosed transmission line(GIL),the analysis of the coating measure’ s restriction mechanism forthe metal-particle lifting is carried outin this paper.Based on the theory of gas ionization and the interface charge accumulation,the model of the metal particle’s charging and lifting on the coatings under DC voltage is proposed.Furthermore,the concept of the charging timeis defined according to the time-varying characteristics of the particle-charging.To verify the correctness of the models,the multi-function test platform of metal-particle’ s charging and moving is established.Experiments are carried out on the spherical metal particles with different sizes andmaterials,and the PET films with different thicknesses under DC voltage.The results validate the accuracy of the model,i.e.the coating measure just increases the particle-charging time and has no effect on the final charge,but the effect of the electrostatic adsorption force can significantly improve the lifting voltage;applied voltage,coating’s permittivity and bulk conductivity have significant effect on the charging time;and due to the existence of the charging time,the phenomennon of " intermittentlifting" will appear.更多还原