Model-based Robust Fault Diagnosis And Simulation

In recent years,with the rapid development of science and technology,the control system of industrial mass production is becoming more and more complex,and the requirements for the safety of the system are getting higher and higher,and the fault diagnosis is through the collection of system information and through certain analysis.Handle and discover system faults in time to ensure stable and normal operation of the system.Therefore,fault diagnosis is a hot research issue in the field of modern control.Model-based fault diagnosis is a widely used method in the field of fault diagnosis.In practical applications,due to factors such as system uncertainty and unknown external disturbance,it is difficult to establish an accurate model and the accuracy of fault diagnosis will be under this circumstance,the status of model-based robust fault diagnosis is highlighted.By constructing the observer to generate robust residuals,the residuals are robust to external disturbances and other influencing factors,thus effectively improving faults.The accuracy of the diagnosis.The main research contents of this paper are as follows:Firstly,the purpose and development status of the research on fault diagnosis are introduced.After the definition of fault diagnosis is described,several basic fault diagnosis methods are introduced.At the same time,the model-based robust fault diagnosis is introduced.Principles and methods.Secondly,the fault diagnosis based on unknown input observer using the interference decoupling idea to generate the residual is studied.By combining the interference decoupling method and the linear matrix inequality in the unknown input observer,the research is based on the NUIO/ LMI fault diagnosis method,the residual generated by this method is robust to unknown interference and system uncertainty,and the feasibility of the method is verified by satellite attitude control system.Then,the fault diagnosis based on multi-index constrained observer using the optimization idea to generate residuals is studied.The H_- index describes the robustness of the residual to the interference,the H_? norm describes the sensitivity of the residual to the fault.By making a compromise between these two performance indicators,the residual generator is constructed to generate the corresponding robust residual,which cannot be directly utilized.The fault system of the H_- index,the construction of the residual generator with the aid of the output is studied.Finally,based on the threshold generation in model-based robust fault diagnosis,the threshold generation method based on the L_? norm is studied and combined with the H_- index,based on research the H_-/ L_? fault diagnosis method of the observer is applied to the simulation experiment of the single flexible manipulator to demonstrate the effective operation and feasibility of the method.