摘要
套管作为变压器高压端与外壳之间的重要绝缘部件,运行过程中容易受到长期的电、热、机械应力等作用形成缺陷,严重威胁电力设备的稳定运行。本文先以现场运行的缺陷变压器套管为对象,开展了介质损耗、电容量、局部放电等电气特性诊断试验;然后模拟套管电容屏破损空洞缺陷,测量了试样的介质损耗因数、电容量以及频域介电谱,对比典型缺陷套管样品和正常套管样品之间的特征参量差异;利用缺陷套管模型,开展局部放电试验并分析其局部放电特征参量,研究放电次数、放电量与放电概率之间的关系。结果表明:当变压器套管电容屏发生破损空洞缺陷时,其介质损耗因数增幅可达25%,电容量增加幅度可达15%;放电量-放电概率图谱的偏斜度可作为识别电容屏破损空洞缺陷的特征参量。
As an important insulating component between the high-voltage end and the outer shell of transformer, bushing is easy to suffer long-term electrical, thermal, and mechanical stress during operation and form defects, which would seriously threaten the stable operation of power equipment. In this paper,taking a transformer bushing with defect in field operation as object, and its dielectric loss factor, capacitance, and partial discharge were tested. Then a broken fault of capacitive screen for bushing was simulated, and its dielectric loss factor, capacitance, and frequency domain dielectric spectroscopy were tested.The difference of characteristic parameters between typical defective bushing and normal bushing was compared. The fault bushing model was conducted partial discharge experiments to analyze the characteristic parameters of partial discharge, and the variation characteristics among discharge number, discharge capacity, and discharge probability were studied. The results show that when the capacitive screen of transformer bushing suffers broken fault, its dielectric loss factor can be increased by 25%, and the capacitance can be increased by 15%. The skewness of the discharge capacity-discharge probability map can be used as the characteristic parameter for recognizing the broken fault of capacitive screen.
作者
朱文兵
辜超
王建
朱孟兆
周加斌
朱庆东
ZHU Wenbing;GU Chao;WANG Jian;ZHU Mengzhao;ZHOU Jiabin;ZHU Qingdong(State Grid Shandong Electric Power Research Institute,Jinan 250003,China)
出处
《绝缘材料》
CAS
北大核心
2019年第8期84-89,共6页
Insulating Materials
关键词
变压器套管
缺陷
故障检测
局部放电
介电特性
transformer bushing
defects
fault detection
partial discharge
dielectric property
