针对局部均值分解(Local Mean Decomposition,LMD)方法提取电梯导靴振动信号的故障特征分量时存在的模态混淆现象,本文提出了一种基于奇异值分解(Singular Value Decomposition,SVD)优化局部均值分解(Local Mean Decomposition,LMD)的...针对局部均值分解(Local Mean Decomposition,LMD)方法提取电梯导靴振动信号的故障特征分量时存在的模态混淆现象,本文提出了一种基于奇异值分解(Singular Value Decomposition,SVD)优化局部均值分解(Local Mean Decomposition,LMD)的电梯导靴振动信号故障特征提取方法。该方法以奇异值贡献率原则构造原始信号的Hankel矩阵,采用SVD对Hankel矩阵进行分解;将曲率谱原则与奇异值贡献率原则相结合对奇异值进行选择,将包含主要故障信息的奇异值进行逆重构,得到剔除噪声信号与光滑信号的突变信号;并利用LMD方法对突变信号进行故障特征提取,得到能够突出原始信号振动特征的故障特征分量。实例结果表明该方法有效改善了LMD的模态混淆现象,更准确地提取了振动信号的故障特征分量,为电梯导靴的故障诊断提供了一条有效的途径。展开更多
Severe production conditions in coal mines cause damage and failure problems with the oriented sliding boots of the mechanical shearer. Wear has been an especially vexing problem. Plasma cladding methods were used to ...Severe production conditions in coal mines cause damage and failure problems with the oriented sliding boots of the mechanical shearer. Wear has been an especially vexing problem. Plasma cladding methods were used to study optimized sliding boot design. By cladding the substrate steel the surface may be made of a material more resistant to wear. The iron based alloy Cr4MnTi was coated onto a modified 45 steel matrix material in these tests. The results show that the alloy cladding layer is high strength, has high hardness, and is highly resistant to wear. After hardening and tempering, 45 steel substrate has great tenacity so the combined structure meets the performance requirements for the construction of shearer sliding boots.展开更多
文摘针对局部均值分解(Local Mean Decomposition,LMD)方法提取电梯导靴振动信号的故障特征分量时存在的模态混淆现象,本文提出了一种基于奇异值分解(Singular Value Decomposition,SVD)优化局部均值分解(Local Mean Decomposition,LMD)的电梯导靴振动信号故障特征提取方法。该方法以奇异值贡献率原则构造原始信号的Hankel矩阵,采用SVD对Hankel矩阵进行分解;将曲率谱原则与奇异值贡献率原则相结合对奇异值进行选择,将包含主要故障信息的奇异值进行逆重构,得到剔除噪声信号与光滑信号的突变信号;并利用LMD方法对突变信号进行故障特征提取,得到能够突出原始信号振动特征的故障特征分量。实例结果表明该方法有效改善了LMD的模态混淆现象,更准确地提取了振动信号的故障特征分量,为电梯导靴的故障诊断提供了一条有效的途径。
基金Financial support for this work, provided by the fundingsupport: the National Natural Science Foundation General Projects(No. 51075387)the National "Eleventh Five-Year" Plan Major Projects supported by the National Science and Technology (No.2008BAB36B02)
文摘Severe production conditions in coal mines cause damage and failure problems with the oriented sliding boots of the mechanical shearer. Wear has been an especially vexing problem. Plasma cladding methods were used to study optimized sliding boot design. By cladding the substrate steel the surface may be made of a material more resistant to wear. The iron based alloy Cr4MnTi was coated onto a modified 45 steel matrix material in these tests. The results show that the alloy cladding layer is high strength, has high hardness, and is highly resistant to wear. After hardening and tempering, 45 steel substrate has great tenacity so the combined structure meets the performance requirements for the construction of shearer sliding boots.
