改进小波阈值新算法在电网扰动中的去噪研究  

Research on denoising of improved wavelet threshold algorithmapplied to power grid disturbance

作　　者：张镇涛 刘明萍[1] 余勃文 张震[1] 汪庆年[1] ZHANG Zhentao;LIU Mingping;YU Bowen;ZHANG Zhen;WANG Qingnian(Information Engineering School,Nanchang University,Nanchang 330031,China)

机构地区：[1]南昌大学信息工程学院,江西南昌330031

出　　处：《现代电子技术》2021年第9期53-57,共5页Modern Electronics Technique

基　　金：国家自然科学基金(61865011);国家自然科学基金(61665006);江西省自然科学基金(20162BCB23012);江西省自然科学基金(20171ACB21018)。

摘　　要：针对电网扰动信号检测中噪声引起的干扰问题,传统的软、硬阈值方法去噪效果不理想,文中提出一种改进阈值函数结合自适应调节阈值的去噪新算法。采用该算法同传统软、硬阈值函数法、软硬阈值折衷算法对Matlab模拟的三相短路故障信号进行仿真实验,定量比较分析后的结果表明:所提算法能够有效地解决噪声干扰的问题,信噪比提升,均方根误差减少,通过对实验信号提取特性曲线,数据分析后显示扰动特征保留较好,波形综合恢复程度较高,能为后续电网扰动信号分析提供有效的信息。A new denoising algorithm integrating the improved threshold function and adaptive adjustment threshold value is proposed to deal with the interference caused by noise in the process of power grid disturbance signal detection and the unsatisfactory denoising effect of the traditional soft and hard threshold methods.The proposed algorithm,the traditional soft threshold function method,hard threshold function method and the soft and hard threshold value compromised method are used to conduct a simulation experiment of the three⁃phase shortcircuit fault signals simulated with Matlab.The results of the quantitative comparison analysis show that the proposed algorithm can eliminate the noise interference better,improve the signal⁃to⁃noise ratio(SNR)and reduce the root mean square error(RMSE).The data analysis for the signal characteristic curve extracted in the experiment indicates that the signal disturbance characteristics remain better and the comprehensive restoration level of its whole waveforms is superior.Therefore,the proposed algorithm can provide effective information for the subsequent analysis of power grid disturbance signal.

关 键 词：信号去噪 阈值调节 扰动信号 扰动特征 去噪算法 实验分析 

分 类 号：TN911.7-34[电子电信—通信与信息系统] TN911.4[电子电信—信息与通信工程]