一例500kV避雷器缺陷数据的分析及思考

The Analysis on a Group of Test Data of 500 kV MOA with Default and Its Discussion

在运行电压下测量金属氧化物避雷器的阻性电流,对判断避雷器是否存在受潮或老化等缺陷有重要意义;而普遍存在的"一"字形排列的避雷器,测试阻性电流不可避免地会受到相间干扰的影响。介绍了阻性电流测试原理及测试时相间干扰情况,并结合一组500 kV避雷器缺陷试验数据,指出目前较为普遍使用的抗干扰校正算法所存在的不足,认为:对于MOA初期的缺陷,不建议使用仅采集电流信号的单输入型测试仪器进行测试;对于边单相缺陷引起的初期故障,使用校正算法容易造成结论的误判断,不建议采用此方法;可通过在相同的周围环境下,依据MOA阻性电流测试的增量来判断其性能状态;初次的阻性电流测试可以和停电直流试验一同进行,以监测试品的运行状况。

Resistance current measurement of Metal Oxide Arrester（MOA） under operating voltage possesses important significance of judging the MOA whether it incurred the inchoate aging or damping. It is not avoidable influence from the interphase disturbing when measure the resistive current of MOA ubiquitously arranged in line mode. The Principle of the measurement of the resistive current and the interphase disturbing of MOA measurement was introduced, and combined with deficiencies test data of a set of 500 kV Arrester, the shortcoming of statics algorithm which is popular at present is indicated, considered that for the initial defect of MOA, it does not recommend the use of single-input test equipment of only gathering current signal for testing; for early failures caused by single side phase defects; it is easy to cause miscarriage of justice of conclusion by using emendation arithmetic, it is not recommended; through the same surrounding en- vironment, the performance status could be determined according to increment of MOA＇s resistive current; initial test of the resistive current can be carried out with power cut DC test, to monitor the operating status of test sample.