纸板老化对油纸绝缘针板放电的影响

Influence of Paper-ageing on Needle-plate Discharge of Oil-paper Insulation

为了研究绝缘纸板老化对油纸绝缘针板放电发展过程的影响,构建了油纸绝缘针板放电的试验平台,其中包括针板放电模型、变压器环境模拟以及局部放电监测系统。在此试验平台上,模拟不同老化程度绝缘纸板在变压器内部发生的针板放电过程,并采用逐步升压法加速针板放电的发展。在采集局部放电信息的同时,用照相方法记录纸板上的碳化痕迹,观测不同老化程度纸板针板放电的产生、发展直至发生闪络。结果表明:随着纸板老化程度的逐步加深,针板放电模型的局部放电起始电压和闪络电压逐步下降,放电量和放电次数逐步增长,并且针板放电对纸板的破坏逐渐加重。

In order to study the influence of paper-ageing on the develop process of needle-plate dis- charge for oil-paper insulation, a test platform was established to simulate the needle-plate discharge of oil-paper insulation, which included needle-plate discharge model, transformer environment simulation parts, and partial discharge （PD） monitoring system. With this experimental platform, the needle-plate dis- charge process of the insulation paperboard with different ageing degrees in transformer was simulated, and then the needle-plate discharge was accelerated by gradually voltage-rising method. Meanwhile, the carbonization trace on the paperboard was recorded by camera to observe the PD generation, develop, and flashover process of the paperboard with different ageing degrees. The results show that with the increase of ageing degree, the partial discharge inception voltage and flashover voltage of the needle-plate discharge model decrease, while the discharge capacity and discharge number increase, and the damage of paperboard becomes more serious. These results provide basis to evaluate the effects of paperboard ageing on the needle-plate discharge of oil-paper insulation.