500 kV氧化锌避雷器阀片老化缺陷试验分析

氧化锌避雷器是电力系统中限制过电压的主要保护设备之一,为了保证电力系统安全运行,对氧化锌避雷器进行在线监测以实时了解其运行状态,及时发现氧化锌避雷器的异常现象及事故隐患是十分必要的。文中对500 kV MOA不同位置老化情况进行了试验,通过红外成像装置及MOA阻性电流测试仪研究分析了MOA的温度及各电气参数的变化情况。试验结果表明:MOA单节电阻片老化严重时,温度变化最显著的是其相邻节;在MOA电阻片严重老化时,红外热成像技术可以作为判断MOA老化位置的依据,而MOA各电气参数并不能作为判断MOA老化位置的依据;红外测温技术与泄漏电流带电检测技术相结合可作为MOA在线监测的有效手段。文中在试验室对500 kV MOA不同老化位置下各个电气参数及整体温度分布情况进行了试验研究分析,因氧化锌避雷器实际运行时的周围环境与试验室环境差异较大,文中所得结论仅供读者参考。

Experimental Study on Valve Strip Aging of 500 kV Zinc Oxide Arrester

To ensure safe operation of electricpower system,it is necessary to online monitor the zinc oxide arrester(MOA)to understand its running state and find outits abnormal phenomena and hidden dangers in time.In this study,the aging of a 500 kV MOA in different positions was tested.The temperature and the change of the electrical parameters of MOA were analyzed by infrared imaging device and MOA resistive current tester.The results show that:①when single section of MOA valve strip suffers severe aging,the adjacent section is subjected to the most significant change of temperature;②in the case of severe aging of the MOA valve strip,the infrared thermal imaging technique can be used to judge the aging position of MOA,while the electrical parameters of MOA cannot be used to judge the aging position due to their low sensitivity to aging;③the infrared temperature measuring technology combined with the leakage current live inspection technology is effective for online monitoring of MOA.Moreover,the electrical parameters and the overall temperature distribution of the 500 kV MOA with different aging positions were tested and analyzed in laboratory.Because the actual operation environment of MOA is quite different from the laboratory environment,the conclusions from this study are merely areference.