Research On Decentralized Fault-tolerant Control For Interconnected Nonlinear Time-delay Systems

With the increasing complexity of the production equipment processes,the single nonlinear system model could no longer meet the modeling requirements of modern industrial productions.Interconnected nonlinear systems,which could be utilized to describle complex industrial production processes,have attracted considerable attention of many scholars.The interconnected nonlinear systems are composed of several interconnected nonlinear subsystems,which have the characteristics of coupling and uncertainty.In interconnected nonlinear systems,the influence of time-delay or actuator faults on the stability of subsystems will be transmitted to other subsystems through interaction.Therefore,it is of great significance to study the control strategy for interconnected nonlinear systems with time-delay and actuator faults.To solve the aforementioned problems,a decentralized fault-tolerant control method is studied in this paper for a class of interconnected nonlinear time-delay systems by combining the dynamic surface control and adaptive control with broad learning systems.The main research contents of this paper are summarized as follows:(1)For a class of interconnected nonlinear systems with unstructured uncertainties,unknown time-delay functions,and actuator faults,a state observer is constructed in this paper by utilizing the broad learning systems to estimate the system states and unknown time-delay functions,and identify the unstructured uncertainties.In order to tackle the effect of actuator faults on system stability,a decentralized fault-tolerant tracking control strategy based on adaptive fault estimation is proposed in this papaer by utilizing the dynamic surface control.(2)For a class of interconnected nonlinear time-delay systems with input quantization,unstructured uncertainties,unknown time-delay functions,and actuator faults,an effective quantization strategy is developed to reduce the effect of quantization errors and chattering on the considered systems.On account of the limited communication resources in network control,the static event triggering mechanism is studied in this paper,and then a decentralized fault-tolerant tracking quantized control strategy is proposed based on the static event-triggered technique.(3)For a class of interconnected nonlinear time-delay systems with unstructured uncertainties,unknown time-delay functions,and actuator faults,a nonlinear observer based on the broad learning systems is designed in this paper to estimate the system states and actuator faults,simultaneously.In order to further save the communication sources,a decentralized fault-tolerant tracking control strategy utilizing the dynamic event-triggered technique is proposed in this paper by introducing an internal dynamic variable.