基于非抽样提升小波包和奇异值分解液阀故障诊断.pdf

学兔兔 第47卷第9期 机 械 工 程 学 报 Vo1．47 No．9 201 1年 5月 JOURNAL 0F MECHANICAL ENGINEERING Mav 201 1 DoI：10．3901／JME．2011．09．072 基于非抽样提升小波包及奇异值分解的液阀 故障诊断水 陈敬龙 张来斌 段礼祥 胡 超 (中国石油大学(北京)机械与储运工程学院 北京 102249) 摘要：针对液阀故障微弱信号特征识别问题，提出一种结合非抽样提升小波包(Undecimated lifting scheme packet，ULSP)及奇 异值分解(Singularvalue decomposition，SVD)的降噪方法。确定信号的分解层次及各层初始算子的长度后，通过拉格朗日插值 公式算出初始算子，用非抽样算法对原始信号进行分解。对最后一层各频带信号进行奇异值分解降噪处理，根据奇异熵增量 曲线确定降噪阶次。用非抽样提升小波包的重构算法对信号进行重构，最终获得降噪后的信号。对降噪后的信号再进行非抽 样提升小波包分解，以提取故障特征。对仿真信号的降噪表明，所提方法降噪获得较高的信噪比及较低的均方差，且能保留 信号中应有的高频成分。提出的方法成功提取某往复式注水泵排水阀弹簧失效的微弱故障特征。 关键词：非抽样提升小波包 奇异值分解 液阀 故障诊断 中图分类号：TH17 Diagnosis of Liquid Valve Based on Undecimated Lifting Scheme Packet and Singular Value Decomposition CHEN Jinglong ZHANG Laibin DUAN Lixiang HU Chao (College of Mechanical and Transportation Engineering，China University of Petroleum(Beijing)，Beijing 1 02249) Abstract：Aiming at the extraction offailure character signal for liquid valve，a novel method to combine undecimated lifting scheme packet(ULSP)with singular value decomposition(SVD)is developed．Initial operators are calculated by using Lagrange interpolation formula after determining decomposition level and the lengths of initial operators，and then the original signal is decomposed by using undecimated algorithm．All frequency bands signals of the last layer are denoised by using SVD thresholding，a reasonable order for noise reduction is selected according to the singular entropy of singular spectrum．Then signal is reconstructe