基于电压增量的非线性模拟电路软故障诊断

基于节点电压增量关系方程理论,根据高阶故障对低阶故障的覆盖性,并结合替代原理,提出了一种可以诊断非线性模拟电路软故障的字典法,将仅应用于线性模拟电路软故障诊断的方法推广到了含有少量非线性元件的模拟电路。将非线性元件作为一个整体,利用节点电压增量关系方程的线性相关系数作为统一故障特征,实现了电路中非线性元件和线性元件集的硬故障、软故障、单故障和多故障的诊断。给出了含有单个或多个非线性元件的电路诊断方法,并用最小距离法对容差做了相应的处理,最后通过仿真实例证明了该诊断方法的有效性。

Node-voltage increments based soft fault diagnosis of nonlinear analog circuits

Based on the theory of node-voltage increments relation functions and according to the substitution theory and another important character: high-rank faults cover low-rank faults,a soft fault diagnosis dictionary method for nonlinear analog circuits is presented to extend the node-voltage increments relation function method from diagnosing soft faults of linear analog circuits to those of nonlinear analog circuits.Considering the nonlinear components as a whole,the linear relativity coefficient of node-voltage increments relation functions is utilized as a unified fault feature to diagnose hard faults,soft faults,single faults and multiple faults of the nonlinear and linear components sets according to the dictionary.The diagnosis methods of circuits with single or multiple nonlinear components are discussed,and the least distance method is applied to handle the tolerance problem.Finally,simulation results prove the efficiency of the proposed method.