基于改进 SVD_EMD 的绝缘子泄漏电流去噪方法

泄漏电流是表征气体绝缘输电线路(GIL)内部绝缘子性能优劣的重要指标，在实际工程中泄漏电流信号的采集常受窄带信号与白噪声信号的干扰，进而影响对于绝缘子性能的准确评估，常用泄漏电流去噪方法多依赖于经验参数与人工设定。针对以上问题，提出利用奇异值曲率谱对奇异值变换(singular value decomposition,SVD)进行改进，去除窄带信号干扰;然后引入正负白噪声组，利用经验模态分解(empirical mode decomposition,EMD)对含有白噪声信号的泄漏电流信号进行分解，在分解过程中对模态分量进行去噪处理，保留最终模态分量即为无噪泄漏电流信号。信号仿真与现场实测结果均表明所提方法可以有效实现GIL绝缘子泄漏电流去噪。

Improved singular value and empirical mode decomposition algorithm on leakage current denoising

Leakage current is an important indicator to characterize the performance of GIL internal insulator. In practical engineering, the acquisition of leakage current signal is often interfered by narrow-band signal and white noise signal, which affects the accurate evaluation of insulator performance. The common methods of leakage current denoising rely on empirical parameters and manual settings. In order to solve the above problems, singular value decomposition ( SVD) is improved by using singular value curvature spectrum to remove narrowband signal interference. Then, the positive and negative white noise groups are introduced, and the leakage current signal with white noise is decomposed by empirical mode decomposition ( EMD). In the decomposition process, the modal component is denoised, and the final modal component is the noiseless leakage current signal. The results of signal simulation and field measurement show that the proposed method can effectively denoise the leakage current of GIL insulator.