基于参考信号频域半盲提取的机械故障特征声学诊断

Acoustic diagnosis of mechanical fault feature based on reference signal frequency domain semi-blind extraction

针对生产现场机械设备零部件结构复杂、设备运行时背景噪声干扰严重等造成的监测诊断难题,以及传统盲信号处理算法在机械声信号处理方面的局限性,提出一种基于参考信号约束频域半盲提取的机械故障声学诊断算法。详细介绍了该算法的关键技术:以频域盲解卷积算法为基础,使用利于全局寻优的人工鱼群算法,构建适用于机械故障特征的改进多尺度形态学滤波器,以最大程度削弱背景噪声干扰;结合机械设备零部件结构参数构建参考信号,通过单元参考信号约束频域半盲提取算法,对降噪后的信号逐段进行复数盲分离;利用改进KL距离,解决复分量间次序不确定性问题,最终实现机械故障特征信号的提取与分离。实际声场环境中的滚动轴承故障声学诊断实验验证了该算法的有效性。

Aiming at fault diagnosis problems caused by complex machinery parts,serious background noises and the application limitations of traditional blind signal processing algorithm to the mechanical acoustic signal processing,a failure acoustic diagnosis based on reference signal frequency domain semi-blind extraction is proposed.Key technologies are introduced：Based on frequency-domain blind deconvolution algorithm,the artificial fish swarm algorithm which is good for global optimization is used to construct improved multi-scale morphological filters which is applicable to mechanical failure in order to weaken the background noises;combining the structural parameters of parts to build a reference signal,complex components blind separation is carried out on the signals after noise reduction paragraph by paragraph by reference signal unit semi-blind extraction algorithm;then the improved KL-distance of complex independent components is employed as distance measure to resolve the permutation,and finally the mechanical fault characteristic signals are extracted and separated.The actual acoustic diagnosis of rolling bearing fault in sound field environment results proves the effectiveness of this algorithm.