混杂系统参数故障诊断

Parametric fault diagnosis for hybrid system

针对混杂电力电子系统中的参数性故障诊断问题,文中使用节点电压法对混杂电力电子系统进行描述,将电路的参数故障诊断问题转变为线性规划方程最优解的存在性判断问题,从而对参数性故障进行诊断并估计故障元件参数。以逆变电路作为混杂系统的研究对象,在考虑存在误差的情况下,采用节点电压方程描述电路,利用线性规划方程解的存在性来判断逆变电路的故障状态;使用电压增量比值作为故障特征值,建立故障字典,并计算故障状态下的电压增量比,进行故障隔离;对于无解或解不为零的方程,通过添加修正参数求解,从而得出故障值。最后,将逆变电路作为混杂系统的研究对象进行仿真验证。结果表明,文中方法操作简单、准确率高,可较为准确地进行混杂电力电子系统的参数性故障诊断与参数辨识。

In allusion to the diagnosis of parametric fault in the hybrid power electronic system,the node voltage method is used to describe the hybrid power electronic system to convert the circuit parametric fault diagnosis into the existence judgment of the optimal solution of the linear programming equation,so as to diagnose the parametric fault and estimate the parameter of the faulty component. Taking the inverter circuit as the research object of the hybrid system,the node voltage equation is used to describe the circuit,and the existence of the linear programming equation solution is used to judge the fault state of the inverter circuit in the case of considering the error existence. The fault dictionary is established by taking the voltage increment relative value as the fault feature value,and the voltage increment relative value in fault state is calculated,so that the fault isolation is performed. In allusion to equations that have no solution or a non-zero solution,the fault value can be obtained by adding correction parameters. The simulation verification was carried out by taking the inverter circuit as the research object of the hybrid system. The results show that method has the advantages of simple operation and high accuracy,and can be used for parametric fault diagnosis and parameter identification of hybrid power electronic system.