基于主元核相似度免疫机制的故障诊断方法及应用

Fault diagnosis based on immunity strategy with similarity measurement of principle component kernel and its application

关键词:  航空发动机  故障诊断  免疫理论+  主元核+  距离判别法+

Key words:  Aeroengine  Fault diagnosis  Immune theory~+  Principle component kernel~+  Distance discriminance~+

摘要:

为了解决传统距离判别函数法在故障诊断中存在误差较大等问题,基于主元核理论和免疫系统机制,提出了基于主元核相似度免疫机制的故障诊断方法。该方法在免疫形态空间中采用主元核形式的相似性度量,将已知故障模式中的每个样本看作一个抗体,将待检样本看作抗原,把故障诊断问题转化为抗体对抗原的识别问题。应用实例表明,该方法受故障模式分布结构的影响较小,当故障样本分散程度较大,聚类性较差时,仍能得到较好的诊断结果。

Abstract:

To solve the problem that exists in fault diagnosis based on the traditional method using distance discriminant function,an improved method based on immunity strategy with similarity measurement of principle component kernel was presented for aircraft engines.Based on the theory of principle component kernel and immunity strategy,the similarity measurement in immunity space is in the form of principle component kernel.Thus each certain sample is regarded as an antibody,and the sample to be recognized is regarded as an antigen.So the fault diagnosis can be converted into the process of antibody recognizing antigen.The practical application results show that the distribution structure of fault modes has little effect on the method proposed,and when the clustering samples are scattered greatly,the diagnosis results are still accurate.