基于Lagrange插值的局部特征尺度分解方法及其应用

发布时间：2018-02-26 10:44

本文关键词： 局部特征尺度分解 Lagrange插值故障诊断不对中故障时频分析　出处：《湖南大学学报(自然科学版)》2017年04期 　论文类型：期刊论文

【摘要】：针对局部特征尺度分解(Local Characteristic-scale Decomposition,LCD)方法中均值曲线插值点的属性主要由相邻两同类极值点的属性决定,不能很好地体现数据的整体变化趋势,从而可能引起分解精度降低,提出了基于Lagrange插值的局部特征尺度分解(Lagrange Interpolation based Local Characteristic-scale Decomposition,LILCD)方法.该方法采用Lagrange插值取代LCD中的线性插值,且均值曲线的插值点是由相邻的3个同类极值点构成的Lagrange插值多项式计算产生.引入了对称系数的概念,并给出了最优对称系数评价准则.研究了LILCD方法的原理及最优对称系数评价准则,通过仿真信号将LILCD方法与LCD方法进行了对比,结果表明LILCD在提高分量精确性和正交性方面具有一定的优越性.将LILCD方法应用于转子不对中故障的诊断,结果表明了方法的有效性.
[Abstract]:The attributes of mean curve interpolation points in the local feature scale decomposition (LCD) method are mainly determined by the attributes of two adjacent extreme points of the same class, which can not well reflect the overall variation trend of the data, and may lead to a decrease in the resolution accuracy. Based on Lagrange interpolation, a local eigenscale decomposition method named Lagrange Interpolation based Local Characteristic-scale DecompositionLILCDD is proposed, in which Lagrange interpolation is used to replace the linear interpolation in LCD. The interpolation point of mean curve is generated by Lagrange interpolation polynomial which is composed of three adjacent extremum points of the same class. The concept of symmetric coefficient is introduced. The principle of the LILCD method and the evaluation criterion of the optimal symmetric coefficient are studied. The LILCD method and the LCD method are compared by the simulation signal. The results show that LILCD has some advantages in improving the accuracy and orthogonality of components. The application of LILCD method to the fault diagnosis of rotor misalignment shows the effectiveness of the method.
【作者单位】：湖南大学汽车车身先进设计制造国家重点实验室;安徽工业大学机械工程学院;
【基金】：国家自然科学基金资助项目(51375152) 湖南省科技支撑计划资助项目(2014WK3005)~~
【分类号】：TH17

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