X射线激励下局部放电的研究进展

Review on X-Ray Induced Partial Discharge

X射线具有较大的能量,能使电介质发生电离,进而可以影响局部放电的发生与发展过程。首先介绍X射线激励固体绝缘内部气隙、油纸绝缘内部气隙和油隙等典型缺陷局部放电的宏观现象,综述X射线能够为绝缘体中的气隙放电提供给初始电子,减小放电统计时延,降低局部放电起始电压的机理。其次,阐述近年来X射线激励下GIS绝缘子中气隙缺陷、环氧树脂浸渍绝缘中气隙缺陷和油纸绝缘系统等绝缘结构中的局部放电现象和特性。最后,总结现有X射线激励下局部放电检测技术的应用场景,给出该技术的发展和应用前景。

X-ray has the capability to ionize the dielectrics due to its relative high energy,and itmay have a potential influence on partial discharge(PD)process.In this paper,the PD phenomenainduced by X-ray are explained,such as void discharge in solid insulation,void discharge and oil gapdischarge in oil-paper insulation.Then,the mechanism of the X-ray induced PD is reviewed,includingX-ray would supply enough electrons for voids,decrease the statistical lag of voids and reduce thepartial discharge inception voltage(PDIV).After that,the application of X-ray induced PD techniquesin the GIS main insulation,the epoxy resin casting insulation and the oil-paper insulation aresummarized.Last but not the least,the future research emphasis on X-ray induced PD techniques ininsulation assessment is revealed.