具有持续扰动的时滞系统的最优跟踪控制

针对在外部持续扰动下的线性时滞系统提出了一种最优跟踪控制的逐次逼近算法。首先将状态向量含有时滞的线性系统的最优跟踪问题转化为最优调节问题，然后利用逐次逼近算法，将既含有时滞项又含有超前项的两点边值问题转化为不含时滞项和超前项的线性两点边值问题族得到调节系统的最优控制律，然后可以通过截取最优控制序列的有限项得到调节系统的前馈-反馈次优控制律，最后再将最优控制问题转化为最优跟踪问题。     

不确定时滞系统的滑模控制及其应用研究

研究了一类带有控制时滞的不确定性系统的滑模变结构控制器的设计问题。定义特殊线性变换,将原不确定时滞系统化为无时滞系统。在新坐标下,提出了基于二次型性能指标的最优滑模面的设计方法;选择适当的动态不连续控制律保证了系统状态在有限时间到达滑模面,并有效的削弱了抖振。提出并证明了原系统渐近稳定的充分条件。将该控制方法应用到典型的不确定时滞对象——聚合反应釜的温度控制系统中,仿真结果表明了该方法的有效性。     

带有持续扰动非线性系统的最优跟踪控制

研究具有外界持续扰动的非线性系统的无静差最优跟踪控制问题。首先基于内模原理构造一扰动补偿器,将系统化为无扰动的增广系统。然后利用灵敏度法推导出了该系统的最优跟踪控制律。仿真实例表明了该设计方法的有效性。     

Design of an Optimal Preview Controller for Dual-Rate Linear Discrete-Time Systems

A dual-rate preview control strategy for a type of discrete-time system is proposed based on the theory of multirate control. First, by using the discrete lifting technique, the general dual-rate discrete-time system is converted into a single-rate augmented system. On this basis, the augmented error system is constructed by introducing a first-order difference operator and the previewable reference signal. Then the tracking problem is transformed into a regulator problem of the augmented error system. The optimal preview control law of the augmented error system is obtained by using standard linear quadratic optimal preview control theory, and then the optimal preview controller of the original system is derived. In addition, the necessary and sufficient conditions for the controller are given.Finally, simulation results show the effectiveness of the proposed method.     

动态输出反馈网络控制系统鲁棒控制器设计

研究了具有不确定时延的动态输出反馈网络控制系统鲁棒控制器设计问题.考虑小于等于一个采样周期的不确定时延,将动态输出反馈网络控制系统建模为含有不确定性的离散时变系统.利用Lyapunov理论和矩阵不等式方法,推导出系统鲁棒控制律存在的条件,并转化为矩阵不等式表示的可行性问题,从而可利用Matlab LMI工具箱来求解,以便构造鲁棒控制律.Matlab仿真算例说明分析方法和结果是有效可行的.     

带有持续扰动的线性系统的前馈-反馈最优控制

研究具有已知动态特性但未知初始条件的持续外界扰动作用下线性系统的前馈-反馈最优控制问题。利用求解Riccati方程和矩阵方程推导出前馈．反馈最优控制律。给出了前馈-反馈最优控制律的存在唯一性条件，并提出了最优控制律的实现算法。仿真结果表明，该方法易于实现且抑制外部持续扰动的鲁棒性优于经典反馈最优控制。     

一类非线性互联大系统的近似最优扰动抑制

研究一类受外界扰动非线性互联动态大系统的最优扰动抑制问题。根据有限时域二次型性能指标,提出了一种基于逐次逼近思想的大系统近似最优扰动抑制方法。利用该方法将由原系统得到的高阶耦合的非线性两点边值问题简化为一族解耦的线性两点边值问题序列。证明了该序列的解一致收敛于原非线性互联大系统的最优控制。通过截取最优控制序列的有限次逼近值,可以得到非线性互联大系统近似最优扰动抑制控制律。最后通过数值仿真表明了该方法的有效性。     

Feedforward and feedback optimal control for linear time-varying systems with persistent disturbances

1 .INTRODUCTIONIn nature ,there are various external disturbancesaffecting the performances of systems . Many con-trol problemsinvolve designing a controller capableof stabilizing a given linear system while mini mi-zing the worst-case response to some additive dis-turbances . This problemis relevant to disturbancerejection and cancellation. One application area ofinterest is flight control through wind shear ,where disturbances arise from a modal for windshear based on harmonic oscillati…     

基于自适应未知输入观测器的多故障快速重构

针对一类非线性函数中耦合执行器故障的非线性动态系统, 提出一种基于自适应未知输入观测器的多故障快速重构方法, 通过引入比例项提高故障重构的快速性。首先, 将执行器故障进行解耦处理并构建包含传感器故障的增广系统。然后, 综合H_∞性能指标给出状态估计误差的稳定性证明。接着, 将观测器增益矩阵的求解转化为受线线矩阵不等式约束的非线性优化问题, 并实现执行器故障和传感器故障的多故障重构。最后, 结合单关节柔性机器人算例仿真验证了所提方法的有效性。     

线性状态多时滞系统鲁棒故障诊断滤波器设计

研究一类具有外部扰动的不确定线性时滞系统的鲁棒故障诊断滤波器设计问题。通过引入一种广义坐标变换,使得线性连续状态多时滞系统变为输出灌入(outputinjection)系统;据此,引入一种体现残差对故障信号具有灵敏性同时对不确定性扰动具有鲁棒性的性能指标,应用H∞最优控制理论,借助线性矩阵不等式(LMI)技术设计系统的状态全维鲁棒故障诊断滤波器,并给出该滤波器问题解的存在条件和求解算法。最后给出一个仿真算例,仿真结果表明了该算法的有效性和可行性。     

同时含状态和输入时滞系统的最优滑模控制

研究了一类线性时滞系统的变结构控制器的设计问题。为了简化变结构控制器的设计,首先通过非奇异线性变换将含状态时滞和输入时滞的线性系统化为无时滞系统。其次,在新坐标下,设计变结构控制器。结合二次型性能指标最优控制方法,给出了线性无时滞系统最优滑模的综合设计方法。引入趋近律方法设计控制律,有效的削弱了抖振并能保证系统在有限的时间内到达滑模面。最后,提出并证明了原系统渐近稳定的充分条件。仿真例证了该方法的有效性。     

New type of adaptive control for a class of distributed time-delay systems with adaptation regard to delay parameter

The problem on stabilization for the system with distributed delays is researched. The distributed time-delay under consideration is assumed to be a constant time-delay, but not known exactly. A design method is proposed for a memory proportional and integral (PI) feedback controller with adaptation to distributed time-delay. The feedback controller with memory simultaneously contains the current state and the past distributed information of the addressed systems. The design for adaptation law to distributed delay is very concise. The controller can be derived by solving a set of linear matrix inequalities (LMIs). Two numerical examples are given to illustrate the effectiveness of the design method.     

一类状态不完全可测时滞系统的镇定问题

考虑了一类状态不完全可测时滞系统的镇定问题。对于状态不完全已知的时滞系统，利用线性矩阵不等式和系统变换技巧，给出了时滞系统的观测器的具体构造，并且基于设计的观测器，给出了系统的稳定性判据和只包含观测状态的控制律。由于判据中需要的参数是由线性矩阵不等式解出的，不是事先估计选定的，减少了结论的保守性。最后给出了数例仿真，通过Matlab软件的仿真，说明了所设计方法的有效性。     

一类模糊时滞系统的非脆弱H∞保成本容错控制

应用线性矩阵不等式方法研究TS模糊系统的H∞保成本容错控制器的设计问题。针对含有容许的不确定参数和可能的执行器故障的模糊时滞系统,在考虑保成本函数取得最小上界的基础上,兼顾系统的H∞性能。以线性矩阵不等式的形式给出TS模糊系统H∞保成本容错控制器存在的充分条件,把控制器的设计问题转化为线性矩阵不等式的可行解问题。通过例子验证了所给出的H∞保成本容错控制器设计方法的可行性和有效性。     

Markov跳变系统的单步约束预测控制

针对离散Markov跳变系统,研究带输出约束的单步预测控制问题。首先设计基于模态的单步预测控制器,驱动系统状态到达相应的终端不变集内,以此保证约束预测控制系统的稳定性,接着进一步讨论了系统存在峰值有界噪声输入情形。其中终端不变集是通过在预测时域外寻求一个虚拟的带约束的状态反馈控制器以保证系统的随机稳定性来获得,为计算方便,控制器的优化问题转化为SDP问题,并得到以LMI描述的优化问题。最后对Markov跳变系统描述的经济学动力系统的仿真结果说明了本控制器设计方法能够在峰值有界噪声输入下保证系统的稳定性,并且使控制变量满足给定的约束条件。     

基于T-S模糊模型的离散不确定时滞系统的容错控制

研究了一类离散不确定时滞模糊系统的容错控制问题。针对非线性离散系统，构造T-S模型，引入参数不确定项和时滞项，使得模糊模型能够更精确逼近原系统。基于T-S模糊模型，利用Lyapunov方法，证明了所采用的模糊控制律使得闭环模糊系统对于执行器故障以及传赢器故障具有完整性和鲁樟挂。不确定项具有范数有界时，利用求解线性矩阵不等式（LMI）的方法，得出了闭环模糊系统在执行器故障以及传意器故障时具有完整性的充分条件。仿真结果说明了该方法的有效性。     

Receding horizon H∞ control for constrained time-delay systems

A receding horizon H∞ control algorithm is presented for linear discrete time-delay system in the presence of constrained input and disturbances. Disturbance attenuation level is optimized at each time instant, and the receding optimization problem includes several linear matrix inequality constraints. When the convex hull is applied to denote the saturating input, the algorithm has better performance. The numerical example can verify this result.     

Modeling genetic regulatory networks: a delay discrete dynamical model approach

Modeling genetic regulatory networks is an important research topic in genomic research and computational systems biology.This paper considers the problem of constructing a genetic regulatory network(GRN) using the discrete dynamic system(DDS) model approach.Although considerable research has been devoted to building GRNs,many of the works did not consider the time-delay effect. Here,the authors propose a time-delay DDS model composed of linear difference equations to represent temporal interactions among significantly expressed genes.The authors also introduce interpolation scheme and re-sampling method for equalizing the non-uniformity of sampling time points.Statistical significance plays an active role in obtaining the optimal interaction matrix of GRNs.The constructed genetic network using linear multiple regression matches with the original data very well.Simulation results are given to demonstrate the effectiveness of the proposed method and model.     

Receding horizon H∞ control for constrained time-delay systems

A receding horizon H∞ control algorithm is presented for linear discrete time-delay system in the presence of constrained input and disturbances. Disturbance attenuation level is optimized at each time instant, and the receding optimization problem includes several linear matrix inequality constraints. When the convex hull is applied to denote the saturating input, the algorithm has better performance. The numerical example can verify this result.     

H∞ fault estimation for a class of linear time-delay systems in finite frequency domain

This paper deals with the problem of H∞ fault estimation for linear time-delay systems in finite frequency domain. First a generalized coordinate change is applied to the original system such that in the new coordinates all the time-delay terms are injected by the system's input and output. Then an observer-based H∞ fault estimator with input and output injections is proposed for fault estimation with known frequency range. With the aid of Generalized Kalman-Yakubovich-Popov lemma, sufficient conditions on the existence of the H∞ fault estimator are derived and a solution to the observer gain matrices is obtained by solving a set of linear matrix inequalities. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.