基于相关分析的非线性模拟电路参数型故障诊断方法.pdfVIP

第26 卷 第9 期 控 制 与 决 策 2011 年 9 月 Vol. 26 No. 9 Control and Decision Sep. 2011 文章编号: 1001-0920 (2011) 09-1407-05 基于相关分析的非线性模拟电路参数型故障诊断方法 邓 勇, 师奕兵 ( 电子科技大学自动化工程学院，成都610054) 摘 要: 针对非线性模拟电路故障诊断中参数型故障元件定位的难题, 基于Volterra 频域核的频谱比较, 提出了利 用小波滤波器组结合相关分析定位故障元件的方法. 首先选择特定的激励信号测定Volterra 频域核的非参数频谱; 然 后用小波滤波器组对得到的正常电路和故障电路的频谱序列进行子带分解; 通过计算子带响应序列的相干函数, 对 正常电路和故障电路进行相关分析, 实现参数型故障元件的特征提取. 对比实验结果表明, 该方法能有效提取故障特 征, 提高了故障诊断效果. 关键词: 参数型故障；非线性模拟电路；Volterra 核；子带滤波；相关分析 中图分类号: TN707 文献标识码: A Approach of parametric fault diagnosis in nonlinear analog circuits based on correlation analysis DENG Yong SHI Yi-bing (School of Automation Engineering，University of Electronic Science and Technology of China ，Chengdu 610054，China. Correspondent ：DENG Yong ，E-mail ：y den117@126.com) Abstract: For the problem of parametric fault diagnosis in nonlinear circuits, an approach based on the comparison of Volterra frequency-domain models, the wavelet filtering technology and correlation analysis is proposed. Firstly, the output signals of the fault-free and faulty circuits excited by selected input signals are filtered by wavelet packets. Then, the coherence functions of the output signal sequences in eight subbands are computed. By the correlation analysis between the fault-free and faulty circuits, different states of the circuits are identified and the faults are located. The simulation results show that the proposed method can extract the fault signature effectively and improve the fault diagnosis. Key words: parametric faults ；nonlinear analog circuits ；Volterra kernel ；wavelet subband filtering ；correlation analysis 1 引引引 言言言 将Volterra 核置于子带