Research On Robust Fault Detection Method For Generalized Uncertain Systems And Its Application In Rolling Force Control System

With the deepening of the application of control system in the field of automation,the complexity of the system is increasing,and the failure rate of control devices is also increasing.Any failure may affect the normal operation of the system,even cause the system to paralyze and cause enterprise economic losses.Fault detection and diagnosis technology is an effective way to improve system performance and reliability,and it has become a hot research field.Model-based fault detection method is an effective in fault detection and diagnosis technology.However,the uncertainty of the system,noise,and the presence of external disturbance signals may have a great impact on the fault detection system,and even lead to the system incorrect alarm.Therefore,the model-based fault detection and diagnosis system has high sensitivity to faults and must be robust to system uncertainties,noise,and external interference signals.This thesis considers the H_-/H_? as performance index,research the fault detection problem of the generalized uncertain system in the finite frequency domain,and applies the research results to the rolling control system.The main research contents of the paper are as follows:The fault detection observer design problem for a generalized uncertain system in finite frequency domain is discussed.By using generalized Kalman-Yakubovich-Popov(GKYP)lemma and projection lemma,the sensitivity conditions and new robustness in finite frequency domain are given.The conditions and the new linearization method are used to transform the conditions into linear matrix inequalities.The stability condition of the fault detection observer is obtained by projection lemma.However,when the above three conditions are combined,it becomes a multi-objective convex optimization problem.By using the method of variable matrix expansion,the non-convex problem in the conditions of robustness and sensitivity is transformed into a bilinear matrix inequality.Finally,an iterative linear matrix inequality algorithm is given to find the optimal solution.Two simulation examples verify the effectiveness of the method.Finally,the proposed method is applied to sensor failure detection of rolling force control system.