基于虚拟可及测试节点的模拟电路故障诊断

Fault Diagnosis in Analog Circuits Based on Virtual Accessible Testing Nodes

针对网络撕裂方法诊断模拟电路故障过程中撕裂节点必须是可及节点的限制,提出了虚拟可及测试节点的方法。利用网络拓扑结构和基尔霍夫电流定律计算一类不可及测试节点故障电压,让其成为虚拟可及测试节点。然后在可及或虚拟可及测试节点对网络进行撕裂,再根据故障电压和故障判据定位故障至更小的区域,从而进一步定位故障元件。这种新方法降低了待诊断电路中对可及节点数目的要求,增加了撕裂的灵活性。通过仿真实例验证了该方法的有效性。

Against the limitation of tearing nodes that must be accessible in analog circuit diagnosis based on tearing technology, the method of virtual accessible testing nodes was presented. The virtual accessible testing nodes were transformed from the inaccessible nodes whose nodal voltages under faulty condition can be computed by topological structure and Kirchhoffs Current Law. The decomposition nodes could be either the accessible testing nodes or the virtual accessible testing nodes. According to faulty voltages and faulty criterion, locating of faulty sub-networks was implemented and faulty components could be located. The new method reduces the requirements for the number of accessible testing nodes and increases the flexibility of decomposition in analog circuit diagnosis. An example circuit was provided to validate the efficiency of the proposed method.