摘要
针对离心式风机运行过程中遇到的联轴器不对中故障特征,将风机负荷和转速变化过程中采集到的振动加速度信号进行经验模态分解(empirical mode decomposition,简称EMD),得到包含特征频率的本征模态函数(IMF),应用粗差检测中常用的3σ准则对每个IMF进行硬阈值去噪处理;然后,分别建立其自回归(AR)模型,进行自回归谱分析。研究结果表明:离心式风机联轴器不对中故障频率除了基频外,以2倍频为主,随负荷增大,转速上升,不对中引起的振动加剧,3次谐波峰值变化显著,并伴有高次谐波的存在。
Aimed at the vibration signal feature of the coupling misalignment fault during operation of centrifugal fan,the empirical mode decomposition method is used to analyze the effect of the load and the speed change on misalignment fault frequency and its peak.Intrinsic mode functions containing specific frequency can be obtained from the decomposed fault signals.To eliminate the noise influence on the AR model,the 3σ criterion by hard valve value is used to depress noise included in every IMF,and then its AR model is established for the spectrum analysis.It is indicated that the second-harmonic peak is the dominating component,besides the base frequency,and the third-harmonic peak changes significantly while the load and the rotational speed rise,and the vibration caused by misalignment is aggravating.
出处
《振动．测试与诊断》
EI
CSCD
北大核心
2011年第5期582-585,663,共4页
Journal of Vibration,Measurement & Diagnosis
基金
吉林省教育厅科学技术研究资助项目(编号:2007047)
关键词
离心式风机
经验模态分解
AR模型
不对中
centrifugal fans empirical mode decomposition(EMD) AR model misalignment
