不确定时滞离散非线性系统的鲁棒耗散滤波

研究了一类带参数不确定性和非线性动态的离散时滞系统的鲁棒耗散滤波问题.所给系统中的不确定项是时变未知且范数有界.基于Lyapunov稳定性方法,先对参数已知而带有非线性动态的时滞离散系统,给出渐近稳定判据,然后讨论鲁棒耗散滤波器的存在条件及设计方法.在此基础上进一步考虑参数不确定性情形,将鲁棒耗散滤波器问题转化为参数确定的情况.从而将鲁棒耗散滤波器的设计问题转换为线性矩阵不等式的求解问题.最后给出仿真例子验证所得结果的有效性.     

不确定时滞双线性广义系统的鲁棒耗散控制

针对带有耗散不确定性的时滞双线性广义系统的鲁棒耗散控制问题,首先将耗散不确定性引入双线性广义系统,利用线性矩阵不等式方法给出系统鲁棒稳定且严格耗散的充分条件;然后利用线性矩阵不等式的解,构造出闭环系统鲁棒耗散的状态反馈控制器;最后通过数值算例验证了所得结论的可行性.     

离散广义系统的严格耗散分析与控制

对离散广义系统,考虑了关于二次型供给率严格耗散控制问题.建立了严格耗散与扩展严格正实之间的等价性.利用线性矩阵不等式(LMI),给出了离散广义系统严格耗散的充分必要条件,并着重推导了其成立的严格LMI条件.针对输入向量维数等丁状态向量维数的系统,分别利用非严格LMI及严格LMI,讨论了状态反馈下的严格耗散控制问题,并给出控制器的设计方法.也讨论了输入向量维数小于状态向量维数的情况.最后通过仿真算例说明所给方法的有效性和普遍性,同时显示了严格LMI条件在耗散控制问题中,比非严格LMI具有的优势.     

一类不确定广义时滞系统的鲁棒耗散控制

将耗散不确定性引入到不确定广义系统中,在状态空间下,通过线性矩阵不等式(LMI)的方法,研究了一类不确定广义时滞系统的鲁棒耗散控制问题.给出了此类不确定广义系统严格耗散的充分条件,然后设计了此类不确定广义系统的鲁棒耗散控制器,最后通过数值算例验证了定理的可行性.     

一类网络控制系统的非脆弱耗散滤波器设计

针对网络化控制系统的滤波器参数存在摄动的问题,考虑到传感器-滤波器存在随机时延和丢包,设计对系统待估信号进行估计的加性非脆弱耗散滤波器,其中滤波器参数具有范数有界不确定性。首先使用Lyapunov稳定性理论和线性矩阵不等式分析方法,推导出耗散滤波器存在的充分条件,在此基础上考虑到滤波器参数不确定性,从而将非脆弱耗散滤波问题转化为求解线性矩阵不等式的问题,然后通过求解线性矩阵不等式得到非脆弱耗散滤波器的参数表达式,最后数值仿真验证了设计方法的有效性。     

线性广义系统基于观测器的严格耗散控制

研究线性广义系统基于观测器的严格耗散控制器的设计问题。首先利用Lyapunov函数的方法,由矩阵不等式的形式给出满足要求的基于观测器的控制器存在的一个充分条件,保证闭环广义系统容许（即正则、稳定、无脉冲）且严格耗散。进而在上述条件的基础上,通过矩阵缩放技术和矩阵等价变换得到由线性矩阵不等式（LMI）形式给出的满足要求的控制器的存在条件和设计方法。最后给出一个数值算例说明设计方法的有效性及可行性。     

具有多包数据丢失非线性系统的耗散模糊滤波

研究一类存在多包数据随机丢失非线性滤波系统的模糊滤波器设计问题, 采用T-S模糊模型对非线性系统进行建模, 并用已知概率分布的二进制切换序列来描述数据多包随机丢失现象. 基于线性矩阵不等式方法给出了模糊滤波器存在的充分条件, 该条件保证所设计的模糊滤波器使得滤波误差系统均方指数稳定且满足期望的耗散性能指标. 最后通过数字仿真例子说明了设计方法的有效性.     

Robust extended dissipative control for sampled-data Markov jump systems

This paper investigates the problem of the sampled-data extended dissipative control for uncertain Markov jump systems. The systems considered are transformed into Markov jump systems with polytopic uncertainties and sawtooth delays by using an input delay approach. The focus is on the design of a mode-independent sampled-data controller such that the resulting closed-loop system is mean-square exponentially stable with a given decay rate and extended dissipative. A novel exponential stability criterion and an extended dissipativty condition are established by proposing a new integral inequality. The reduced conservatism of the criteria is demonstrated by two numerical examples. Furthermore, a sufficient condition for the existence of a desired mode-independent sampled-data controller is obtained by solving a convex optimisation problem. Finally, a resistance, inductance and capacitance (RLC) series circuit is employed to illustrate the effectiveness of the proposed approach.     

Robust dissipative control for linear systems with dissipative uncertainty and nonlinear perturbation

This paper focuses on the problem of dissipative control for linear systems which are subjected to dissipative uncertainty and matched nonlinear perturbation. Specifically, quadratic dissipative uncertainty is considered, which contains norm-bounded uncertainty, positive real uncertainty and uncertainty satisfying integral quadratic constraints (IQCs) as special cases. We develop a linear matrix inequality (LMI) approach for designing a robust nonlinear state feedback controller such that the closed-loop system is quadratic dissipative for all admissible uncertainties. Furthermore, under some condition on the dissipative uncertainty, we show that the controller also guarantees the asymptotic stability of the closed-loop system. As special cases, robust H_∞ control and robust passive control problems for systems with nonlinear perturbation and norm-bounded uncertainty (respectively, generalized positive real uncertainty) are solved using the LMI approach.     

非线性中立型时滞系统的鲁棒耗散控制

研究了非线性中立型时滞系统的鲁棒耗散控制问题,系统包含状态时滞和非线性不确定性,基于Lyapunov稳定性理论,给出了该类时滞系统在非线性不确定性满足增益有界的条件下耗散控制器存在的充分条件,并通过线性矩阵不等式(LMI)方法构造得出耗散控制状态反馈律,最后给出一个数值算例验证了本文结果的有效性.     

An LMI approach to dencentralized H8 control

We consider the design of a decentralized controller for a linear time invariant (LTI) system. This system is modelled as an interconnection of subsystems. For every subsystem, a linear time invariant controller is sought such that the overall closed loop system is stable and achieves a given H performance level. The main idea is to design every local controller such that the corresponding closed loop subsystem has a certain input-output (dissipative) property. This local property is constrained to be consistent with the overall objective of stability and performance. The local controllers are designed simultaneously, avoiding the traditional iterative process: both objectives (the local one and the global one) are achieved in one shot. Applying this idea leads us to solving the following new problem: given an LTI system, parameterize all the dissipative properties which can be achieved by feedback. The proposed approach leads to solving convex optimization problems that involve linear matrix inequality constraints.     

不确定时滞系统的鲁棒耗散控制

耗散不确定性是已经被广泛讨论的范数有界的不确定性和正实不确定性的广义化,因此,从二次型供给率的角度,将耗散不确定性引入线性时变时滞系统,研究了含有此类不确定性的线性时滞系统的鲁棒耗散控制问题,给出了线性矩阵不等式（LMI）形式的充分条件。而且,考虑了不确定时滞系统在状态反馈控制器作用下的闭环系统的耗散控制问题,同样给出了LMI形式的充分条件,并通过线性矩阵不等式的可行解构造出鲁棒耗散的状态反馈控制器。最后。通过实例证明了定理的可行性。     

Dissipative based adaptive reliable sampled-data control of time-varying delay systems

This paper is concerned with the problem of dissipative based adaptive reliable controller for a class of time delay systems subject to actuator failures and time-varying sampling with a known upper bound on the sampling intervals. By constructing a proper Lyapunov-Krasovskii functional which fully uses the available information about the actual sampling pattern and time delays, a new set of sufficient conditions is derived to obtain the required result. Then, a dissipative based adaptive sampled-data controller is designed such that the resulting closed-loop system is reliable in the sense that it is asymptotically stable and has the prescribed dissipative performance under given constraints. The existence condition of the desired dissipative based adaptive reliable sampled-data controller is obtained in terms of linear matrix inequalities. Further, the performance of the proposed controller is implemented on a liquid propellant rocket motor with a pressure feeding system model. The simulation results show the effectiveness and better performance of the proposed adaptive reliable sampled-data controller over conventional reliable controller.     

Decentralized robust control of multiple static var compensators via Hamiltonian function method

Using the energy-based Hamiltonian function method, this paper investigates the decentralized robust nonlinear control of multiple static var compensators (SVCs) in multimachine multiload power systems. First, the uncertain nonlinear differential algebraic equation model is constructed for the power system. Then, the dissipative Hamiltonian realization of the system is completed by means of variable transformation and prefeedback control. Finally, based on the obtained dissipative Hamiltonian realization, a decentralized robust nonlinear controller is put forward. The proposed controller can effectively utilize the internal structure and the energy balance property of the power system. Simulation results verify the effectiveness of the control scheme.     

一种基于多决策类的贝叶斯粗糙集模型

针对传统贝叶斯粗糙集理论只能处理二决策类的不足,提出一种基于多决策类的贝叶斯粗糙集．在此基础上定义一个衡量条件属性对决策属性影响程度的γ 依赖度函数,并证明了该函数具有随条件属性的增加而单调递增的性质．最后基于γ 依赖度函数的单调特性,提出一种确定属性权重的算法．以某钢厂１５０ｔ转炉的实际生产数据为例,仿真结果表明了模型的有效性和实用性．     

滞后离散广义系统的鲁棒严格耗散控制

研究确定的及不确定的滞后离散广义系统的无记忆状态反馈严格耗散控制器设计问题.利用线性矩阵不等式(LMI)方法,首先给出滞后离散广义系统容许(即正则、稳定、因果)且严格耗散的条件,然后通过矩阵不等式(MIs)得到无记忆状态反馈严格耗散控制器的存在条件和设计方法;进而针对除E外其余系数矩阵均具有范数有界不确定性的滞后离散广义系统,利用矩阵不等式的解设计鲁棒严格耗散控制器,保证闭环系统广义二次稳定且严格耗散.     

电力系统微分代数模型耗散Hamilton实现

对非线性微分代数模型电力系统的耗散Hamilton实现问题进行了研究．首先提出了非线性微分代数系统的耗散Hamilton实现结构,给出了完成常值耗散Hamilton实现的充分条件;然后证明单机单负荷电力系统必然存在耗散Hamilton实现,并构造出系统的一个耗散Hamilton实现．     

Dissipative control for linear systems by static output feedback

In this article, the problem of static output-feedback dissipative control is investigated for linear continuous-time system based on an augmented system approach. A necessary and sufficient condition for stability and strict (Q,S,R)-dissipativity of the closed-loop system is established in terms of a matrix inequality with free parametrisation matrix. An equivalent characterisation with some slack matrices for numerical solvability is then proposed. Based on this, a necessary and sufficient condition for the existence of a desired controller is given, and a corresponding iterative algorithm is developed to solve the condition. The effectiveness of results developed in this article is demonstrated by some numerical examples.     

Dissipative design of unknown input observers for systems with sector nonlinearities

In this paper a design method for nonlinear Unknown Input Observers (UIO) for a class of nonlinear systems is proposed. This design is based on a dissipative characterization of the existence conditions for such observers made recently by the authors. The main condition corresponds to an abstract incremental dissipativity property of the plant, which can be made computable by the use of LMI techniques for the considered class of systems. This leads to a constructive design method for nonlinear UIOs. Copyright © 2010 John Wiley & Sons, Ltd.