带有饱和执行器的T-S模糊时滞系统的模糊控制

研究了带有饱和执行器及时变时滞的T-S模糊系统的控制律设计问题.利用PDC技术、Razumikhin稳定性理论以及线性矩阵不等式(LMI)方法,建立了闭环模糊系统渐近稳定的时滞依赖的判别条件,给出了模糊控制律的设计方法.通过求解LMI,可以获得闭环模糊系统的吸引域的估计.最后,提出了闭环系统吸引域的估计最大化的模糊控制律的一个设计方法.     

具有极点区域约束的广义模糊系统的输出反馈控制

针对模糊广义系统，将动态输出反馈控制器设计问题转化为一组矩阵不等式的可行解问题，使得闭环系统不仅具有鲁棒性能，而且能把闭环系统极点配置在一个给定的圆形区域内，从而保证系统具有期望的动态性能。     

线性奇异系统的H_2控制:状态反馈情形

研究一类线性奇异系统的H2控制问题,在较为一般的条件下,利用线性矩阵不等式方法给出一个使闭环系统无脉冲模,内稳定,并满足H2性能指标的状态反馈控制器存在的充要条件以及控制器的一族解.数值仿真证实了所提方法的有效性和实用性.     

具有极点约束的线性振动系统的一种主动控制设计:LMI方法

本文讨论具有闭环极点约束的线性振动系统状态反馈主动控制设计问题。极点约束集是左半复平面上一个由圆形和带状区域构成的凸域，以闭环系统的H2指标为优化目标，将该设计问题转化成一个易于计算的线性矩阵不等式（LMI）约束的凸优化问题求解。最后运用本文方法对一个双层隔振系统模型进行状态反馈控制设计，并给出数值仿真结果。     

LMI的广义系统输出反馈H2控制

利用广义系统正常化方法,在较为一般的条件下,把存在输出反馈控制器使得闭环系统无脉冲模,内稳定且满足H2性能指标的充分条件表示成线性矩阵不等式（LMI）的形式.给出的控制器含有可调参数,便于工程应用.     

关于一类不确定非线性系统的鲁棒控制

对于一类同时具有匹配不确定性和非匹配不确定性的非线性系统,结合反馈线性化理论、矩阵不等式、李亚普诺夫稳定性理论和变结构控制,提出了一种鲁棒控制器的设计方法,使得闭环系统是渐近稳定的.     

一类非线性切换关联大系统的分散控制器设计

基于凸组合技术和线性矩阵不等式方法,考虑了一类非线性切换关联大系统的分散状态反馈镇定问题,大系统的关联项由线性和非线性两部分构成,在低维子系统的单个子系统均不能被镇定且存在非线性干扰的情况下,得到了切换关联大系统稳定的一个充分条件.并将其转化为求解线性矩阵不等式问题,相应给出了算法的计算机实现,进而设计出了切换关联大系统的分散控制器和分散切换策略.     

不确定离散模糊系统的最优保性能控制

对一类具有范数有界,时变参数不确定性的离散模糊时间系统和一个二次型性能指标,研究其最优保性能状态控制律的设计问题.通过采用线性矩阵不等式的方法,导出了存在保性能控制律的一个充要条件,进而,证明了该条件等价于一组线性矩阵不等式的可解性问题,并用这组线性矩阵不等式的可行解给出了保性能控制律的一个参数化表示.在此基础上,通过建立并求解一个凸优化问题,给出了最优保性能控制律的设计方法.     

LMI的广义系统输出反馈H2控制

利用广义系统正常化方法,在较为一般的条件下,把存在输出反馈控制器使得闭环系统无脉冲模,内稳定且满足H2性能指标的充分条件表示成线性矩阵不等式(LMI)的形式.给出的控制器含有可调参数,便于工程应用.     

一类具有范数有界不确定性的非线性时滞系统的控制

本文研究了一类具有范数有界不确定性的非线性时滞系统的鲁棒稳定性及其控制问题,结合Lyapunov稳定性定理、线性矩阵不等式及自由权矩阵,给出了系统的状态反馈鲁棒二次稳定的充分条件以及控制器的设计,并建立了一个具有线性矩阵不等式约束的凸优化问题,得到不确定时滞系统的最优状态反馈控制律.仿真示例说明了该方法的可行性.     

一类非线性不确定结构系统的鲁棒饱和主动控制

对一类非线性不确定结构系统研究了在外部干扰下的鲁棒饱和主动控制策略.将质量、阻尼、刚度矩阵都存在不确定的结构系统描述为一种不确定中立系统,采用鲁棒饱和主动控制策略,提出基于线性矩阵不等式的代数解.通过提出的控制方法同时保证了结构系统在模型和参数摄动下以及在控制变量和扰动存在非线性不确定性时的鲁棒稳定.最后通过对一个4层建筑大楼在地震波作用下的主动振动控制仿真证明了该方法的有效性.     

Global exponential stabilization for a class of nonlinear singularly perturbed systems

Abstract

A globally exponentially (asymptotically) stabilizing composite feedback control is proposed in this paper for a general class of nonlinear multiple time‐delay singularly perturbed systems in which the slow subsystem is exponentially stable in the absence of the fast states. The chosen design manifold under this composite feedback control becomes an exact integral manifold and the trajectories of the closed‐loop systems are steered globally along the integral manifold to the origin exponentially, with some guaranteed convergence rate, for all sufficiently small singular perturbation parameter ?.     

Synthesis of fault-tolerant static output feedback controllers for networked control systems

This paper is concerned with the design of static output feedback control laws for stabilizing a networked control system under possible element failures. Multiple faults can occur on sensors, actuators, or other electrical or mechanical componentes. With considering consecutive packet loss and time-varying network-induced delay, the closed-loop system is modeled as an equivalent time-delay system with several possible modes. By constructing a Lyapunov–Krasovskii function, sufficient conditions for the existence of static output feedback fault-tolerant stabilizing controllers are derived. Moreover, by the simultaneous stabilization approach, it is shown that a static output feedback fault-tolerant controller can be obtained by solving linear matrix inequalities (with equality constraints). Simulation results are presented to validate the theoretical results.     

具有类反斜线回滞系统的自适应控制

考虑一类具有类反斜线回滞的不确定非线性系统自适应控制问题.利用神经网络提出了变结构自适应控制方法和近似自适应控制方法,变结构自适应控制方法能保证跟踪误差趋于零,近似自适应控制方法的控制律是光滑的,能保证跟踪误差最终小于任意给定的正数.文中举例说明了结果的有效性.     

Decentralised stabilising controllers for a class of large-scale linear systems

A simple method for computing decentralised stabilising controllers for a class of large-scale (interconnected) linear systems has been developed. Decentralised controls are optimal controls at subsystem level and are generated from the solution of algebraic Riccati equations for decoupled subsystems resulting from a new aggregation-decomposition technique. The method has been illustrated through a numerical example of a large-scale linear system consisting of three subsystems each of the fourth order     

Feedback stabilization of nonlinear Hamiltonian control systems

Abstract

Conditions for feedback stabilization of smooth affine nonlinear Hamiltonian systems such as robotic manipulators are given. Some results existing in the literature are unified and extended. Application to nonconservative bilinear systems in elasticity is illustrated.     

LMI-based robust voltage tracking control for a class of renewable energy systems

This paper introduces a method of robust voltage tracking control for a class of renewable energy systems, which uses a linear matrix inequality (LMI)-based approach. A remodeling method is introduced where the nonlinear model of the renewable energy system is represented as a nonlinear combination of linear subsystems with state-dependent parameters (the so-called linear state-dependent parameter system model, LSDPM). Next, the remodeling method is applied to a boost converter, a photovoltaic (PV) system, and a wind energy conversion system as examples. A robust output voltage tracking approach is proposed based on the LSDPM. Using Lyapunov’s direct method, controller stability analyses are expressed as LMI formulations. Powerful numerical toolboxes then solve for the controller gains. The advantages of this approach include: i) the generalized remodeling technique is applicable to a wide variety of renewable energy systems; ii) it creates a unified LMI-based design framework for multiple control objectives; iii) it provides numerically solved control gains; and iv) it provides robust tracking control for the multiple objectives of renewable energy systems. Using an LMI-based robust voltage tracking controller is an accurate and effective method of control for many types of renewable energy systems. Finally, practical DSP-based experiments are carried out using the buck converter as an example. The satisfactory results of these experiments verify the theoretical derivations for this control method.     

Experimental study on control fins of a small flying vehicle using piezo-composite actuators

A camber morphing control fin design and an all-moving control fin design using piezo-composite unimorph actuators are presented in this paper. The control fin of a small flying object is usually actuated using a servo motor system with an electromagnetic motor. Much research has been conducted to solve the structural complexity of servo actuation systems to convert the rotation of a servo motor to a linear actuation motion. To simplify this structural complexity, several types of smart actuators have been developed, such as bimorph or unimorph actuators with piezoelectric material layers and shape memory alloy actuators. In this study, a camber morphing type control fin and an all-moving type control fin actuated using piezo-composite actuators are designed to evaluate their ability to simplify the structural complexity of the gear transmission and electromagnetic servo motor system or hydraulic actuator system. Within the skin of the control fin, a piezo-composite actuator is mounted and the other end inserted in a slot of the control fin. As the piezo-composite actuator is excited by an electric field, the pitch angle of the control fin is changed. Experimental testing for the pitch rotation angle of a control fin in a 450 V electric field showed the deflection angle of the camber morphing control fin was 1.4° and the rotational angle of the all-moving control fin was 5.4°, which is obtained from the rotation angle magnification linkage structural system.