电缆附件局部放电超声波检测装置的设计与实验

Design and Experiment of Partial Discharge Detector Based on Ultrasonic Wave for Cable Accessories

在分析吸收国内外先进局部放电检测技术的基础上,针对35 kV的GIS开关柜终端,设计研制了基于超声波的电缆附件局部放电在线监测装置。该装置采用了新型压电高分子薄膜贴片作为超声传感器,克服了传统材料灵敏度低的缺点;模拟电缆附件的气隙缺陷情况,实验研究了局部放电超声信号的幅值、平均放电次数与运行电压的关系;设计了电晕放电和内部放电的对比实验,分析了两种放电的相位分布差异情况,验证了超声传播的延迟特性并指出绝缘缺陷的超声定位应用。

This paper analyzes and assimilates the advanced PD detecting methods. For the 35 kV GIS switch termi-nal, a partial discharge detector based on ultrasonic wave is designed and manufactured. The detector is made of pie- zoelectricity macromolecule film which works as ultrasonic wave sensor. This sensor gets over the deficiency of low sensitivity. The internal gap insulation defect of cable accessories is molded and the PD experiment is researched. The relations of the amplitude and average discharge time of ultrasonic single vs work voltage is analyzed. The com-parative experiments of corona discharge and internal discharge are designed. Their difference of phase distribution is analyzed. The ultrasonic delay property is validated and its location application in insulation defect is indicated.