基于故障字典法的模拟电路印制板故障诊断

【作者】 张翼；

【导师】 谭俊杰； 吴国庆；

【作者基本信息】 南京理工大学 ， 兵器工程， 2001， 硕士

【摘要】 本文是对模拟电路故障诊断中的直流字典法的进一步研究。文中分析了字典法存在的问题，提出了改进方法，其中包括：用蒙特卡罗法求各节点电压的容差域；用贝叶斯决策理论来指导模糊集划分；以模糊集为特征进行节点优选；依故障诊断树进行变节点诊断。在此基础上，讨论了字典法的自动实现方法，编制了通用模拟电路直流故障诊断软件。应用表明：上述的改进使编写的故障树准确合理，减少了测试节点数，提高了诊断的正确性和实时性。更多还原

【Abstract】 A further research to the fault dictionary method is presented in this paper. After analyzed the defaults of the fault dictionary method, several techniques to enhance the capability of the d.c. fault dictionary are presented. These include 1) using Monte Carlo analysis to get the node voltage tolerance, 2) using Bayesian decision theory to direct the fuzzy set dividing, 3) selecting nodes by the fuzzy sets, 4) using the fault tree to diagnose the circuit’s fault with varied sum of nodes. After that the approach of automatically generating the fault dictionary is discussed, and a general diagnosis program for analogue circuits has been written to implement these techniques. The practice shows that new methods have made fault tree more exact 5 decreased the total number of test nodes, and enhanced the real-time capability and accuracy of the fault dictionary method.更多还原