内置式特高频传感器出厂检测方法的研究与应用

Research on Delivery Test Methods of Built-in UHF Sensors

内置式传感器的检测性能取决于GIS结构、传感器的布置方式等条件,在运行中对内置式传感器进行拆卸校验困难的情况下,对已安装的内置式传感器开展出厂前的校验工作显得十分重要。笔者以一段待出厂的GIS间隔为试验平台,建立了内置式传感器的检测系统并分别采用了在GIS内部放置局部放电模型及注入人工电压脉冲两种方法对传感器性能进行了校验,通过对数据的分析可以得出:两种测试方法中内置式传感器的响应量均随着与激励源距离的增加而衰减,信号经过L分支后衰减情况比沿同轴直筒传播更为严重;对于同一个传感器,其响应量随着激励信号强度的增大而增大;内置式传感器响应的灵敏度与激励源有关,使用的内置式传感器对脉冲电压信号的响应更为灵敏。内置式传感器的出厂校验对检验GIS厂家在设计产品时选用传感器数量及选择其放置位置的合理性具有重要作用;同时,将内置式传感器在GIS设备运行中采集到的局部放电数据与出厂校验数据进行对比分析,亦是对局部放电缺陷进行判断的重要参考。

The test performance of a built-in sensor depends on the conditions such as GIS structure and arrangement of sensors. If testing the buih-in sensors via disassembly during operation of GIS is difficult, it is of great importance to test the installed built-in sensors in factory. In this study, an interval of ready-for-delivery GIS is taken as the test platform to establish a test system for the built-in sensors. Two methods of placing simulative partial discharge model in and injecting artificial voltage pulses into the GIS are adopted to test the sensors. Test data analysis indicates that： 1）for the two methods, the responses of the sensors attenuate with the increasing distances from the excitation sources to the sensors, and the signal attenuates more sharply after passing through the L-branch than spreading along the coaxial cylinder; 2）for same sensor, its response increases along with the growing excitation signal; 3）the response sensitivity of the built-in sensor depends on the excitation source, and the built-in sensor is more sensitive to voltage pulse signals. It is concluded that the delivery test of the built-in sensors is very important for verifying the reasonability of the number and arrangement of the sensors in the GIS design, and comparative analysis on the partial discharge data collected from the working GIS and the delivery test data can facilitate judgement of partial discharge defects.