Research On Event-triggered Sliding Mode Fault Tolerant Control Of Systems With Actuator Failure

Due to the service life of components,the inherent characteristics of the system and so on,some unknown faults,such as actuators failure,sensors faults and system faults,may often occur in control system,which will lead to that the system performance degrades and even the system is unstable.Therefore,it is required that the control system has fault tolerance ability to against these faults with maintaining an acceptable system performance.Fault Tolerant Control(FTC)has been shown as an effective approach to deal with this problem and many researchers' interesting have been attracted.On the other hand,due to the existing parameter uncertainties and external disturbance,the robustness should be considered in control system design.Sliding Mode Control(SMC)is a powerful tool to eliminate the effects of model uncertain parameters and external disturbance.Hence,it is significant and important to develop fault tolerant and robust control strategies via the approach of combining sliding mode control and fault tolerant control techniques.Moreover,to reduce the communicate rate of system devices,event-triggered mechanism is introduced.However,the introduction of event-triggered mechanism also causes some problems needing to be further studied,for example how do we design an suitable eventtriggered condition to avoid the Zeno behavior,and how do we design a event-triggered sliding mode fault tolerant controller to overcome the effects of the state error induced by event-triggered mechanism and to ensure the reachability of sliding surface.Thus,in this work,the event-triggered Sliding Mode Fault Tolerant Control(SMFTC)design approach has been investigated.The detail contents of this work are listed as follows:The problem of adaptive event triggered SMFTC for a class of uncertain linear system with actuator failure and signal quantization via state feedback is studied.The classical dynamic uniform quantization strategy is employed to quantize data in both sensorcontroller side and controller actuator side.A new adaptive event-triggered SMFTC scheme via state feedback is proposed to stabilize fault closed-loop systems,where the event-triggered condition is based on quantized state vectors.The reachability of the proposed sliding surface can be ensured by the designed control scheme.Furthermore,sufficient conditions under which zeno behavior can be avoided is given,and the interexecution time interval is presented.The problem of adaptive event-triggered SMFTC for a class of uncertain linear system with actuator failure and signal quantization via output feedback is investigated.The classical dynamic uniform quantization strategy is employed for data quantization in both sensor-controller side and controller-actuator side.An event-triggered condition is established based on quantized augmented state vector that includes output measurement vector and dynamic compensator state vector.A new adaptive event-triggered SMFTC scheme via output feedback is proposed to stabilize the fault closed-loop systems,where sufficient conditions for the existence of controller gain matrices are formulated in terms of linear matrix inequalities(LMIs).The reachability of the proposed sliding surface can be ensured by the designed control scheme.Moreover,sufficient conditions under which the zeno behavior can be avoided is given,and the inter-execution time interval is presented.The problem of asynchronous adaptive event-triggered SMFTC for Markov jump systems with actuator failure is investigated.A hidden Markov model is introduced to describe the asynchronous phenomenon of jump modes between plants and controller.The dynamical logarithmic quantizer is applied to signal quantization both in sensorsto-controller and controller-to-actuators sides.A new event-triggered detector condition is developed based on the quantized state vector.Combined with SMC and adaptive control techniques,a new asynchronous adaptive event-triggered SMFTC law is designed,which has ability to guarantee the robust performance of the closed-loop system in the presence of the effects of actuator failures,time delay resulting by event-triggered and signal quantization error.Moreover,the developed asynchronous adaptive event-triggered SMFTC scheme can ensure that the sliding surface converges the defined small domain in finite time.The lower bound for inter-execution time is analyzed and presented,and sufficient condition under which the Zeno behaviors can be avoided is given.The problem of adaptive event-triggered SMFTC for a class of Markov jump systems with actuator failure and state-dependent attacks is investigated.By utilizing a coordinate transformation,the sliding surface is designed in the new coordinate system.The sufficient condition which can ensure the stability of sliding motion is given.To reduce the communication burden of system,a suitable event-triggered condition is developed.To ensure the stability of overall closed-loop control system and reachability of sliding surface,a new adaptive event-triggered SMFTC is proposed.Under the proposed control law,the influence of parameter uncertainties,attacks,actuator failure and state error induced by event-triggered mechanism can be completely compensated.The positive minimal inter–event time interval is estimated,which shows that the Zeno behavior is avoided.The problem of adaptive event-triggered SMFTC for Markov jump stochastic system with hybrid actuator failure and attacks is investigated.A mode-dependent sliding surface is designed,which ensure that sliding motion does not contain Brownian motion variable.Sufficient conditions for the stability of sliding motion are presented in terms of LMIs.To reduce the communication burden,a new suitable event-triggered condition is designed.A new adaptive event-triggered SMFTC strategy is proposed,which can ensure the stability of closed-loop control system and reachability of sliding surface.And under the proposed control law,the effects of external disturbance,actuator faults,hybrid attacks and state error induced by event-triggered mechanism are eliminated.The estimate of positive minimal inter–event time interval is presented,which implies that the Zeno behavior is avoided.