氧化锌避雷器阻性泄漏电流提取方法研究

Study on Extraction Method of Resistance Leakage Current of Zinc Oxide Arrester

避雷器是高压变电站、高压换流站中的重要保护设备,其可保护电气设备免受过电压危害,可保护电气设备绝缘等级。氧化锌避雷器具有强非线性、通流能力强的优点,能够提高电力系统的可靠性。氧化锌避雷器发生故障的原因多是老化、受潮导致泄漏电流增加,内部温度升高,导致避雷器发生热崩溃。氧化锌避雷器阻性泄漏电流中基波分量可表征其内部受潮情况,谐波分量可表征其老化情况,因此可通过提取阻性泄漏电流监测避雷器的工作状态。通过容性泄漏电流补偿法提取了阻性电流,并搭建了仿真模型,仿真结果表明:该方法可准确提取阻性泄漏电流。

Arrester is an important protection equipment in high voltage substation and high voltage converter station.It can protect electrical equipment from overvoltage harm and protect the insulation level of electrical equipment.Zinc oxide arrester has the advantages of strong nonlinearity and strong current flow ability,which can improve the reliability of power system.The main reasons for the failure of zinc oxide arrester are aging and dampness,which leads to the increase of leakage current and the rise of internal temperature,leading to the thermal collapse of arrester.In the resistance leakage current of zinc oxide arrester,the fundamental wave component can characterize its internal damp condition,and the harmonic component can characterize its aging condition.Therefore,the working state of the arrester can be monitored by extracting the resistance leakage current.In this paper,resistive current is extracted by capacitive leakage current compensation method,and a simulation model is built.The simulation results show that this method can accurately extract the resistive leakage current.