摘要
环氧胶浸纸套管具有电气性能稳定、防爆、体积小、重量轻等优点,已被广泛应用于变压器套管和穿墙套管,但其制造工艺复杂,易在生产过程中产生缺陷。为了获得套管缺陷对应的绝缘特征参数,分析了缺陷产生的原因,并在实际套管中进行缺陷模拟,包括套管内部绝缘纸干燥不良,芯体固化过程热应力集中导致的芯体微裂纹,材料脱气不良在芯体中产生气泡等。通过对比测量,研究了不同缺陷套管的绝缘电阻、介质损耗因数tanδ、电容、频域介电谱(frequency-domain dielectric spectroscopy,FDS)、极化和去极化电流(polarization and depolarization current,PDC)等绝缘参数特征。结果表明,缺陷套管tanδ值均比正常套管大,绝缘电阻则较正常套管小,不同缺陷套管的极化电流具有不同的衰减率和稳定值。通过分析不同频段的FDS曲线和PDC变化规律,可有效区分不同套管缺陷。研究成果可为套管出厂试验和现场绝缘诊断提供参考。
Epoxy resin impregnated paper(RIP)bushings are widely used as transformer bushings and wall bushings.This type of bushing has stable electrical properties,explosion-proof,small size,light weight and other advantages.But its manufacturing process is complicated and difficult,improper process control will result in defects.In order to find out the characteristic parameter of defects,some samples are manufactured to simulate defects and their insulation parameters are investigated in this paper.For example,the dry time is shortened and the moisture is not dried completely during the heating&drying process;crack is resulted by uneven release of thermal stress during solidification process;incomplete degassing of material and residual gas creates bubbles in the condenser core.Insulation parameters such as insulation resistance,dielectric loss factor,and capacitance,frequency-domain dielectric spectroscopy(FDS),polarization and depolarization current(PDC)are studied.Test results indicated that all type of defects may lead to a larger tanδbut a smaller insulation resistance than normal bushing,and different defect bushings exhibit different rates of decrease and stability value at the polarization current.By analyzing FDS curves on different frequency bands and the PDC pattern,different bushing defects can be distinguished effectively.This study can provide reference for factory test and on-site test to diagnose the insulation state of the bushing.
作者
谢志成
许佐明
刘泰蔚
张晋寅
邓军
XIE Zhicheng;XU Zuoming;LIU Taiwei;ZHANG Jinyin;DENG Jun(Maintenance&Test center,EHV Power Transmission Company of CSG,Guangzhou 510640,China;State Key Laboratory of Power Grid Environmental Protection,China Electric Power Research Institute,Wuhan 430074,China)
出处
《南方电网技术》
CSCD
北大核心
2021年第12期66-71,101,共7页
Southern Power System Technology
基金
国家自然科学基金资助项目(52007011)。
关键词
环氧胶浸纸套管
缺陷模拟
绝缘特性
介电谱
极化去极化电流
epoxy resin impregnated paper bushing
defect simulation
insulation characteristics
dielectric spectroscopy
polarization and depolarization current
