一种模拟滤波器电路的故障诊断方法

A Fault Diagnosis Method of Analog Filter Circuits

摘要:

针对模拟滤波器电路,提出了一种基于测前仿真和测后仿真相结合的故障诊断方法;在测前仿真环节,通过仿真获取电路正常状态及故障状态的幅频响应曲线,引入“区别度”计算电路故障状态和正常状态的区分程度,从而确定电路的可测故障集,并通过频率选择建立可测故障集的故障字典;在测后仿真环节,通过不同频率的激励获得电路故障状态的测试数据,再利用“区别度”计算测试数据与故障字典中各故障特征的区分程度,通过最小“区别度”实现故障检测及故障元件的定位;最后通过一个滤波器电路仿真实例,基于PSpice仿真和Matlab程序计算实现了基于测前仿真的可测故障集确定和故障字典建立,以及基于测后仿真的故障检测和故障元件定位,验证了文章提出方法的实用性。

Abstract:

For the analog filter circuits,a combined fault diagnosis method based on simulation before test and simulation after test is proposed. During the simulation before test,the amplitude frequency response curves of the normal state and fault states are obtained firstly through circuit simulation,the “difference degree” is used to calculate the distinction between the fault status and the normal state,then the detectable fault set of the circuit is determined,furthermore,fault dictionary of the detectable fault set is established through frequency selection. In the simulation after test step,the test data of the fault states is obtained firstly through different frequency excitation,and then calculate the distinction between the test data and the fault features of the fault dictionary according to the “difference degree”,therefore fault detection and fault location are realized by the minimum of the “difference degree". Finally,a simulation example of a filter circuit is given,during the simulation before test,the detectable fault set determination and the establishment of fault dictionary is realized based on the PSpice simulation and the Matlab program,and also the fault detection and fault location based on simulation after test,which verified the practicality of the proposed fault diagnosis method.