考虑谐波影响的线路型避雷器泄漏电流在线监测方法研究

Research on Leakage Current Online Monitoring Method of Line Type Lightning Arrester Considering Influence of Harmonics

线路型避雷器是电力系统中重要的过电压防护设备,监测其泄漏电流能够准确把握其运行状态,保障其运行可靠性。然而随着新型电力系统中谐波分量的加重,线路避雷器泄漏电流的监测同时受到谐波和环境噪声信号的影响,泄漏电流信号难以准确获取。针对于此,文中考虑谐波和环境噪声的影响,研究线路型避雷器泄漏电流的在线监测方法。首先采取小波阈值联合去噪(CEEMDAN)算法对泄漏电流监测信号噪声进行抑制,在此基础上基于多频点插值理论准确获取泄漏电流监测信号的谐波分量信息。设置校正系数补偿泄漏电流监测信号由于谐波影响而产生的偏差,应用混合粒子群算法制定泄漏电流监测程序,执行监测程序即可实现线路型避雷器泄漏电流的监测。通过实验验证表明:相较于对比方法,应用提出方法获得的泄漏电流监测耗时更短,泄漏电流监测误差数值更小。充分证实提出方法泄漏电流监测效果更佳,适合大力推广使用。

Line type lightning arrester is an important overvoltage protection equipment in the power system.Monitoring its leakage current can accurately grasp its operating status and assure its operation reliability.However,with the aggravation of harmonic components in the new power system,the monitoring of leakage current of line type lightning arrester is affected by both harmonic and environmental noise signals,making it difficult to accurately obtain leakage current signals.In response to this,the influence of harmonic and environmental noise is considered in this pape to study the online monitoring method for leakage current of line type lightning arresters.Firstly,the wavelet threshold joint denoising(CEEMDAN)algorithm is adopted to suppress the noise of the leakage current monitoring signal.Based on this,the harmonic component information of the leakage current monitoring signal is accurately obtained based on the multi frequency point interpolation theory.The correction coefficient is set to compensate for the deviation of the leakage current monitoring signal due to harmonic effects.The hybrid particle swarm optimization algorithm is used to develop a leakage current monitoring program.The monitoring of leakage current of line type arrester can be achieved by executing the monitoring program.It is shown by the experimental verification that compared to the comparison method,the use of the proposed method achieves shorter time consumption of leakage current monitoring and smaller error of leakage current monitoring.It is fully confirmed that the proposed method has better leakage current monitoring effect and is suitable for vigorous promotion and application.