基于子带分析的非线性电路故障诊断.pdfVIP

学兔兔 第32卷 第7期 仪 器 仪 表 学 报 Vo1．32 No．7 2011年7月 Chinese Journal of Scientific Instrument Ju1．2011 基于子带分析的非线性电路故障诊断冰 邓 勇，师奕兵，张 伟 (电子科技大学自动化工程学院，成都 611731) 摘 要：针对非线性模拟电路故障诊断中Volterra级数(Volterra核)计算复杂的难题，基于Voherra核的频谱子带分析，提 了利 用将Voherra核进行子带分解以降低计算复杂度的方法。首先将激励信号分别输入正常电路和故障电路得到两种电路的输出，然 后分别计算正常电路和故障电路的Volterra子带核，通过求解两种电路Voherra子带核的相关系数实现故障元件的特征提取。实 验结果表明，该方法不仅能提高故障诊断效率，还能有效提取灾难型故障(硬故障)和参数型故障(软故障)的故障特征。 关键词：非线性电路；故障诊断；Voherra级数；子带分解；相关系数 中图分类号：TN707 文献标识码：A 国家标准学科分类代码：510．1010 Nonlinear circuit fault diagnosis based on subband analysis Deng Yong，Shi Yibing，Zhang Wei (School of Automation Engineering，University of Electronic Science and Technology ‘China，Chengdu 61 7jJ，China) Abstract：Considering the problem of complex computation of Voherra series(Voherra kerne1)in nonlinear analog circuit fault diagnosis，an approach based on subband decomposition of Voherra kernel for reducing computational complexity is proposed．Firstly，the output signals of fault—free and faulty circuits are obtained under the excitation of input signals．Then，the subband kernels of the fault—free and faulty circuits are computed．The correlation coeffi— cients between the subband kernels of the fault-flee and faulty circuits are used to extract the signatures of the faulty parts．Experiments show that the method proposed in this paper can not only improve fault diagnosis efficiency but also extract the fault signatures of catastrophic and parametric faults effectively． Key words：nonlinear circuit；fault diagnosis；Voherra series；subband decomposition；correlation coefficient