【作者】 吴晰源；

【导师】 李炜；

【作者基本信息】 兰州理工大学 ， 控制理论与控制工程， 2012， 硕士

【摘要】 网络化控制系统(Networked Control System，NCS)是以通讯网络代替传统的点对点连接而构成的闭环控制系统。随着NCS的高速发展及其对可靠性、安全性越来越高的要求，NCS的容错控制得到了高度重视。在对NCS进行容错控制研究时，由于网络的介入，给NCS的建模、分析和设计带来了许多新的问题和挑战，如网络诱导时延、数据丢包、信息量化等等。纵观近年来NCS容错控制研究成果，对于同时考虑时变时延、丢包和量化误差且具有参数不确定性的NCS，以时滞依赖的方法进行鲁棒容错控制研究的结果还少有报道。基于此，本文首先考虑当被控对象的全部状态完全可测时，采用状态反馈策略，以不确定NCS为研究对象，同时考虑网络诱导时延、数据丢包和信息量化误差对系统的影响，基于状态多时延模型，通过构造时滞且量化误差依赖的Lyapunov-Krasovskii泛函，运用Lyapunov稳定性理论和LMI方法，在传感器或执行器故障情况下，研究了不确定NCS的鲁棒完整性以及当系统具有未知有界扰动时的鲁棒H∞完整性问题，推证出了使不确定NCS具有鲁棒完整性及鲁棒H_∞完整性的判决准则以及相应控制器的设计方法。还以执行器失效故障为例，进一步讨论了故障NCS稳定运行的最大允许时延和最大允许量化误差，并以此为依据对H_∞性能指标进行优化，给出了鲁棒H_∞最优容错控制器设计方法。其次考虑当被控对象的全部状态不完全可测时，采用动态输出反馈策略，以不确定NCS为研究对象，同时考虑网络诱导时延、数据丢包和信息量化误差对系统的影响，基于状态多时延模型，通过构造时滞且量化误差依赖的Lyapunov-Krasovskii泛函，运用Lyapunov稳定性理论和LMI方法，在传感器或执行器故障情况下，研究了不确定NCS的鲁棒完整性和鲁棒H_∞完整性问题，推证出了使不确定NCS具有鲁棒完整性及鲁棒H_∞完整性的判决准则，并利用矩阵分离引理，有效地将非线性项进行分离，给出了相应鲁棒容错控制器的设计方法。进而也讨论了执行器故障NCS稳定运行的最大允许时延，并据此对H_∞性能指标进行了优化，给出了鲁棒H_∞最优容错控制器设计方法。最后，采用相应算例对以上的理论结果进行了正确性和有效性的仿真研究。由于模型中考虑了时延下界，且构造了时滞、量化误差共同依赖Lyapunov-Krasovskii泛函，证明过程中引入了适当自由权矩阵变量未进行交叉项放大处理，这均可减少结果的保守性。而对于最大允许时延和最大允许量化误差的分析可以在确保系统不失稳的前提下，进行NCS的优化调度控制，并可据此分析结果保守性的大小，并以较少的保守性进一步提高NCS容错的可行性和满意度。更多还原

【Abstract】 Networked control system(NCS) is a kind of closed loop control system which is based oncommunication network in place of the traditional point-to-point connections. With the highdevelopment of NCS and the high demand of reliability, safety, NCS fault-tolerant control get highattention. In the research of the fault-tolerant control of NCS, the network bring many newproblems and challenges to the modeling, analysis and design of NCS, such as network inducedtime-delay, data packet loss, information quantification, and so on. Review the achievements on thefault-tolerant control of NCS in recent years, there is few paper studying the robust fault-tolerantcontrol of NCS with parameter uncertainties in the way of time-delay dependent, for consideringthe time-varying delay, packet loss and quantization error at a time.Based on this, this paper first considering the whole state of the controlled plant can bemeasured completely, using the state feedback strategy, with the uncertain NCS as the researchobject, considering the influence of network induced time-delay, data packet loss and informationquantification error, through the construction of delay and quantizing error dependent Lyapunov-Krasovskii functional, the problems of robust integrity, robust H_∞integrity of NCS with parameteruncertainties are studyed based on the Lyapunov stability theory and the technique of Linear Matrixinequalities(LMIs). A stability delay-depandent criterion for the closed-loop system with robustintegrity, robust H_∞integrity against actuator or sensor failures are given and the method of therobust fault-tolerant controller design are also given. Also to actuators failures, for example,discusses the maximum allowed time-delay and the maximum allowed quantizing error when theNCS operate stably, and on the basis of this, the optimized H_∞performance indexe and the methodof the optimal robust fault-tolerant controller design are given.Secondly, considering the whole state of the controlled object not complete measurement,using dynamic output feedback control law, taking the unascertain NCS as the research object,considering the influence of the network induced time-delay, data packet loss and informationquantification error, based on the model of state multi-delay time, with construction time-delay andquantizing error dependent Lyapunov-Krasovskii functional, using Lyapunov stability theory andLMI method, in the cases of sensors or actuators failures, the robust integrity and robustH_∞integrity of NCS are studied. The corresponding decision rules are inferred out. Thecorresponding robust fault-tolerant controller design method is given with the nonlinear termseparation effectively by using matrix separation lemma. And then discusses the maximum allowedtime-delay and the maximum allowed quantizing error when the NCS operate stably, and on thebasis of this, the optimized H_∞performance index and the method of the optimal robustfault-tolerant controller design are given.Finally, based on the above conclusions, using simulation examples show that paper concluded that the correct and effective. The less conservative results is obtained since the lowerbound of the time-delay and appropriate free-weighting matrices being introduced, moreoverwithout model transformation, scaling-up of cross terms during the proof. Analysising themaximum allowable delay and the maximum allowed quantizing error can proceed the optimizationscheduling control of NCS while the system is stable, can analysis the conservative of the resultsaccording to the above analysis, and also can improve the feasibility and satisfaction of the faulttolerance of NCS further with less conservative.更多还原