| Author Name | Affiliation | | Zhuo Wang | School of Automation and Electrical Engineering, Dalian Jiaotong University, Dalian 116000, Liaoning, China | | Xiang Zheng | School of Automation and Electrical Engineering, Dalian Jiaotong University, Dalian 116000, Liaoning, China | | Tiantian Liang | School of Automation and Electrical Engineering, Dalian Jiaotong University, Dalian 116000, Liaoning, China |
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| Abstract: |
| Partial discharge (PD) is an important reason for the insulation failure of the switchgear. In the process of PD detection, PD signal is often annihilated in strong noise. In order to improve the accuracy of PD detection in power plant switchgear, a method based on continuous adaptive wavelet threshold switchgear PD signals denoising is proposed in this paper. By constructing a continuous adaptive threshold function and introducing adjustment parameters, the problems of over-processing of traditional hard threshold functions and incomplete denoising of soft threshold functions can be improved. The analysis results of simulated signals and measured signals show that the continuous adaptive wavelet threshold denoising method is significantly better than the traditional denoising method for the PD signal. The proposed method in this paper retains the characteristics of the original signal. Compared with the traditional denoising methods, after denoising the simulated signals, the signal-to-noise ratio (SNR) is increased by more than 30%, and the root-mean-square error (RMSE) is reduced by more than 30%. After denoising the real signal, the noise suppression ratio (NRR) is increased by more than 40%. The recognition accuracy rate of PD signal has also been improved to a certain extent, which proves that the method has a certain practicability. |
| Key words: switchgear partial discharge wavelet threshold function denoising |
| DOI：10.11916/j.issn.1005-9113.21039. |
| Clc Number:TP13 |
| Fund: |
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| Descriptions in Chinese: |
| 基于连续自适应小波阈值开关柜局部放电信号去噪方法 王 卓，郑 祥，梁天添 （大连交通大学 自动化与电气工程学院，大连 116028） 中文说明：局部放电(PD)是开关柜发生绝缘故障的重要原因，而在PD检测过程中，PD信号常常湮没在强烈的噪声中。为提高电厂开关柜PD检测的准确性，提出一种基于连续自适应小波阈值开关柜局部放电信号去噪方法。通过构造一种连续自适应阈值函数，引入调节参数，可以改善传统硬阈值函数过度处理和软阈值函数去噪不彻底的问题。仿真信号和实测信号的分析结果表明，连续自适应小波阈值去噪方法对PD信号去噪效果明显优于传统的去噪方法，很好地保留了原信号的特征，相比于传统的去噪方法，文中的方法对仿真信号去噪后，其信噪比(SNR)提升30%以上，均方根误差(RMSE)下降30%以上，对真实信号去噪后，其噪声抑制比(NRR)提升40%以上，同时该方法降噪后的PD信号模式识别准确率也有一定的提升，证明该方法具有一定实用性。 关键字：开关柜；局部放电；小波阈值函数；降噪； |
