Research Of Iterative Learning Fault Tolerant Control In Finite Frequency Domain

There are many problems when we track the desired trajectory in the engineering systems.Many scholars have done a lot of research in order to solve these problems,and iterative learning control is one of the solutions.Iterative learning control is a branch of intelligent control,which is suitable for the industrial control processes with repetitive operations.It's inevitable that all kinds of failures will occur when the system is running,and the failures occur sometimes in a specific frequency range.Therefore,the iterative learning fault controller is a good choice for the fault control system with specific frequency domain.The system can maintain the desired performance because of the controller.Based on the stability theory of repeated process control,this paper designs iterative learning fault controller in the finite frequency range for fault-tolerant repetitive systems.The linear matrix inequality(LMI)is used to analyze the monotone convergence condition of repeated process system,and the controller parameters are also obtained.The research work of this thesis is summarized as follows:(1)An iterative learning fault-tolerant controller is designed in finite frequency range for linear discrete repetitive process with actuator failures.The sufficient conditions for the stability of the full frequency and division frequency domain repetitive control systems based on Kalman–Yakubovich–Popov(KYP)lemma are given in the form of LMI.At the same time,the fault-tolerance performance of fault system in time domain and frequency domain is guaranteed.The injection speed control simulation of the repetitive injection molding process verifies the effectiveness of the frequency dividing control algorithm.(2)A dynamic iterative learning fault-tolerant control algorithm is designed in finite frequency range for the system stability problem of linear discrete repetitive process with actuator failures.By defining fault coefficient matrix,the output tracking system and designing dynamic iterative learning control law,we can get the equivalent repetitive process model.And the dynamic iterative learning passive fault-tolerant controller along the time axis and batch axis of the fault system is designed.The sufficient conditions for the stability of the system are given based on KYP lemma.The effectiveness of the frequency domain control algorithm is verified by the simulation of the multi-axis gantry robot.(3)The problem of iterative learning fault-tolerant control for a class of linear discrete systems with actuator faults and state delays is researched.An iterative learning fault-tolerant control algorithm based on finite frequency domain is proposed.The sufficient condition for stability of the repetitive control system is obtained in terms of the KYP lemma,and the fault tolerance performance of the fault system in the frequency domain is guaranteed.The injection speed control simulation of the repetitive injection molding process verifies the effectiveness and feasibility of the proposed algorithm.