变压器油纸绝缘沿面放电特性及其产气规律

Surface discharge characteristics and gas generation law in oil-paper insulation of transformer

基于油纸绝缘沿面放电模型,在实验室模拟变压器油箱内进行局部放电试验,研究油纸绝缘沿面放电发展特性及其特征量的变化规律,并着重研究放电发展过程中油中溶解气体的变化特性。实验结果表明,油纸绝缘沿面放电幅值在放电起始阶段呈上升的趋势,放电2～3h幅值达到最大,然后放电强度开始慢慢减弱;随着油纸绝缘局部放电的发展,CO的绝对产气速率以一个值为中心上下波动,变化幅值较小;而油中沿面放电H2和CH4的绝对产气速率先增加再减少,放电谱图变化与油中溶解气体绝对产气速率变化表现出较高的相似性。

Based on a surface discharge model,partial discharge experiment in the simulation transformer tank is carried out to research the development characteristics and characteristic parameters＇ variation law of surface discharge in transformer oil-paper insulation,and the variation characteristic of dissolved gases in oil in the discharge process is emphatically researched.The results show that the surface discharge value increases at the beginning stage of the discharge process,and reaches its maximum after 2~3 h,then it decreases gradually.As the development of partial discharge,the absolute generation speed of CO fluctuates around a certain value with small variation.While,the absolute generation speeds of H2 and CH4 increase first and then decrease,and the variation of discharge spectrum is highly similar to the variation of oil-dissolved gas＇ absolute generation speed.