谐波影响下基于时间积分法的绝缘子在线监测

Insulator On-Line Monitoring Based on Time-Integral Method Considening Harmonics

泄漏电流监测是架空线路绝缘子状态最可靠、最有效的指标。然而,基于泄漏电流的绝缘子状态监测的主要困难在于,难以分辨测量得到的泄漏电流变化的原因是随系统变化的谐波还是污秽等其他因素。研究了在电压谐波存在的情况下,利用泄漏电流时间积分值来监测架空线路绝缘子泄漏电流的可行性。研究结果表明:系统电压谐波分量的变化对泄漏电流的谐波特性有显著影响,但对时间积分的影响相对较小。该监测技术已通过试验数据的验证,并在实验室在线测量装置中得到了应用。

Leakage current is a reliable and effective indicator for condition monitoring of overheadline insulators. However,the main difficulty of using leakage current to monitor the condition of insula-tors is that the cause of the change of leakage current is the harmonics changes with system or the otherfactors such as the contamination. The feasibility of monitoring leakage current of overhead insulators byusing the time integral value of leakage current in the presence of voltage and harmonics is explained. Ac-cording to the research,the change of system voltage and harmonics has a significant effect on the har-monic characteristics of leakage current,but it has little influence on time-integral value. The monitoringtechnology has been verified by off-line test data and applied in online monitoring device.