基于HHT法的煤冲击破坏低频电磁信号去噪  

Denoising Low-frequency Signal from Impact Failure of Coal Based on HHT method

作　　者：付玉凯[1,2,3] 杨威[4] 李成武[4] 

机构地区：[1]天地科技股份有限公司开采设计事业部,北京100013 [2]煤炭科学研究总院开采设计研究分院,北京100013 [3]煤炭科学研究总院煤炭资源高效开采与洁净利用国家重点实验室,北京100013 [4]中国矿业大学(北京)资源与安全工程学院,北京100083

出　　处：《煤矿开采》2015年第4期9-13,35,共6页Coal Mining Technology

基　　金：国家科技支撑计划课题(2012BAB13B02);国家自然科学基金项目(U1261211);中国煤炭科工集团科技创新基金面上项目(2014MS037)

摘　　要：针对煤冲击破坏低频磁场信号的高噪声、非线性、非平稳等特征，将HHT时频分析方法引入到低频磁场信号的时频分析中，介绍了HHT时频分析方法及原理，利用该方法对煤冲击破坏低频磁场信号进行去噪分析和时频处理。研究结果表明： EMD分解重构不但可对信号进行去噪处理，还能很好地刻画出低频电磁信号的非线性、非平稳性及脉冲特性；低频磁场信号的频谱图可清晰表示出能量随时间和频率的动态变化，从频谱图中得出，低频磁场信号的优势频率在0～40 Hz之间，其持续时间小于2 s；与傅里叶变换和小波分析相比， HHT分析方法的时间、频率分辨率较高，有完全的时频局部性，可很好地描述电磁信号的时变特征，是电磁信号时频分析的有效方法。For the high-noise, nonlinear and non-stationary characteristics of low-frequency signal in impact failure process of coal, introducing HHT time-frequency analysis method into low-frequency signal analysis, denoising and time-frequency disposing of low-fre-quency signal was finished with this method.Results showed that EMD decomposition and reconstitution could not only denoise signal, but also describe well nonlinear, non-stationary and pulsing characteristics of low-frequency electromagnetic signal.Spectrogram of low-frequency magnetic signal could clearly show dynamic variation of energy with time and frequency.From spectrogram, dominant fre-quency of low-frequency magnetic signal was within 0~40Hz and its duration was less than 2s.Compared with Fourier transform and wavelet analysis, HHT method has higher time and frequency resolution, whole time-frequency localization and could well describe time-varying characteristic of electromagnetic signal, which is effective method for time-frequency analysis of electromagnetic signal.

关 键 词：HHT法 煤冲击破坏 低频电磁信号 EMD分解 分离式霍普金森杆 

分 类 号：TU45[建筑科学—岩土工程]