基于局部放电法的矿用高压电缆信号去噪算法研究

干扰噪声直接影响局部放电法有效检测矿用高压电缆故障。基于局部放电法，综合采用理论计算、仿真实验、现场试验的方法，对比分析了短时傅里叶变换和傅里叶分析去噪法的原理和优缺点，提出了一种矿用高压电缆的局部放电去噪算法——小波阈值去噪法，同时，选择了合理的阈值函数和去噪流程。基于此，采用白噪声和连续周期信号作为高压电缆的干扰噪声，进行了模拟仿真实验。结果表明，小波阈值去噪法可有效抑制白噪声，其中，Db2小波性能和去噪效果最好；同时，现场试验结果显示，去噪后信噪比得到了显著增加，验证了小波阈值去噪法的合理性和可靠性。

Research on de-noising algorithm of mine high-voltage cable signal based on partial discharge method

The interference noise directly affects the effective detection of mine high-voltage cable fault by partial discharge method.Based on the partial discharge method，the theory calculation，simulation experiment and field test are comprehensively adopted.The principle，advantages and disadvantages of short-time Fourier transform and Fourier analysis denoising method are compared and analyzed.A wavelet threshold denoising algorithm for mining high-voltage cable is proposed.At the same time，reasonable threshold function and denoising process are selected.Based on this，the white noise and continuous periodic signal are used as the interference noise of high voltage cable.The simulation results show that the wavelet threshold denoising method can effectively suppress the white noise.Among them，Db2 wavelet has the best performance and denoising effect.At the same time，the field test results show that the signal-to-noise ratio has been significantly increased，which verifies the rationality and reliability of wavelet threshold denoising method.