基于變分貝葉斯混合獨(dú)立分量分析的機(jī)械故障診斷方法研究
[Abstract]:In this paper, with the support of the National Natural Science Foundation of China (50775208, 51075372) and the Open Fund of the Key Laboratory of Health Maintenance of Mechanical Equipment of Hunan Province (200904), by introducing the theory of Variational Bayesian Mixed Independent Component Analysis into mechanical fault diagnosis, a method of mechanical fault diagnosis based on Variational Bayesian Mixed Independent Component Analysis is proposed. The main contents include the following aspects:
In the first chapter, the background and significance of this topic are introduced in detail. The research status and application status of variational Bayesian theory and independent component analysis theory are summarized. On this basis, the research contents and innovations of this paper are put forward.
In the second chapter, the basic principle of variational Bayesian independent component analysis (vbICA) and its two algorithms (vbICA1 algorithm and vbICA2 algorithm) are discussed. The separation performance of the two algorithms is compared through experiments. The experimental results show that the two algorithms can achieve good separation performance in noise environment. In the process of separation, vbICA2 algorithm can get better separation effect than vbICA1 algorithm, and with the increase of noise, the superiority of vbICA2 algorithm is more obvious. On this basis, the significance of variational Bayesian Mixed Independent Component Analysis is given, and the theory of variational Bayesian Mixed Independent Component Analysis and the theory of variational Bayesian Mixed Independent Component Analysis are discussed in detail. Algorithm. The content of this chapter is the theoretical basis of the whole paper.
In Chapter 3, it is pointed out that when ICA is used to decompose and represent data, it is assumed that the whole data distribution can be completely described in a coordinate system. However, when the observed data are composed of many self-similar, non-Gaussian manifolds, it is inappropriate to simply use a single, global representation, which results in a suboptimal representation. In this paper, based on the variational Bayesian theory, a method of blind source separation for mechanical faults based on the variational Bayesian hybrid independent component analysis is proposed. The simulation results verify the effectiveness of the proposed method. Finally, the proposed method is applied to the source separation of bearing inner and outer ring faults. The experimental results also verify the effectiveness of the proposed method.
In Chapter 4, aiming at the shortcomings of the existing methods for estimating the number of mechanical fault sources, that is, they can only give the upper limit of the number of sources, can not accurately estimate the number of sources, and do not consider the influence of noise interference, a method of estimating the number of mechanical fault sources based on variational Bayesian mixed independent component analysis is proposed. Based on the network, the hybrid independent component analysis (HICA) and variational Bayesian are combined to estimate the optimal number of hidden sources by maximizing the Negative Free Energy (NFE) of the objective function.
In the fifth chapter, the shortcomings of under-determined blind separation method for mechanical fault diagnosis are discussed, that is, the existing under-determined blind separation method does not take into account the noise environment. To overcome this shortcomings, a mechanical fault diagnosis method based on variational Bayesian and mixed independent component analysis is proposed. This method is based on the assumption that the source signals come from different clusters (i.e. manifolds), and an ICA model is established for each cluster. Thus, a ICA hybrid model is generated. Then the ICA hybrid model is studied by using the variational Bayesian method. The mixed matrix can be estimated from the observed signals and the source signals can be recovered by learning. Research and experimental results show that this method is very satisfactory for under-determined blind source separation with less than the number of observed signals.
In the sixth chapter, the research work of this paper is summarized comprehensively, and the further work is prospected.
【學(xué)位授予單位】:鄭州大學(xué)
【學(xué)位級別】:碩士
【學(xué)位授予年份】:2011
【分類號】:TH165.3
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 蘇野平,何量,楊榮震,朱小剛;一種改進(jìn)的基于高階累積量的語音盲分離算法[J];電子學(xué)報;2002年07期
2 倪晉平,馬遠(yuǎn)良,鄢社鋒;基于高階累積量的復(fù)數(shù)混合矩陣盲估計(jì)算法[J];電子與信息學(xué)報;2002年11期
3 譚北海;謝勝利;;基于源信號數(shù)目估計(jì)的欠定盲分離[J];電子與信息學(xué)報;2008年04期
4 劉琨;杜利民;王勁林;;基于時頻域單源主導(dǎo)區(qū)的盲源欠定分離方法[J];中國科學(xué)(E輯:信息科學(xué));2008年08期
5 張朝柱;張健沛;孫曉東;;基于curvelet變換和獨(dú)立分量分析的含噪盲源分離[J];計(jì)算機(jī)應(yīng)用;2008年05期
6 陳仲生,楊擁民,沈國際;獨(dú)立分量分析在直升機(jī)齒輪箱故障早期診斷中的應(yīng)用[J];機(jī)械科學(xué)與技術(shù);2004年04期
7 李志農(nóng);呂亞平;韓捷;;基于時頻分析的機(jī)械設(shè)備非平穩(wěn)信號盲分離[J];機(jī)械強(qiáng)度;2008年03期
8 范濤;李志農(nóng);肖堯先;;基于源數(shù)估計(jì)的機(jī)械源信號盲分離方法研究[J];機(jī)械強(qiáng)度;2011年01期
9 張洪淵,賈鵬,史習(xí)智;確定盲分離中未知信號源個數(shù)的奇異值分解法[J];上海交通大學(xué)學(xué)報;2001年08期
10 徐尚志;蘇勇;葉中付;;欠定條件下的盲分離算法[J];數(shù)據(jù)采集與處理;2006年02期
相關(guān)碩士學(xué)位論文 前4條
1 陳勇;獨(dú)立分量分析在振動信號處理中的應(yīng)用[D];吉林大學(xué);2007年
2 張楠;基于貝葉斯網(wǎng)絡(luò)的汽輪機(jī)振動故障診斷研究[D];華北電力大學(xué)(河北);2007年
3 康斌;獨(dú)立分量分析在機(jī)械振動信號中的應(yīng)用研究[D];武漢理工大學(xué);2008年
4 王琦;基于獨(dú)立分量分析的故障源識別技術(shù)[D];華北電力大學(xué)(北京);2008年
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