基于T-S模型的非线性系统非脆弱保性能模糊控制

针对一类用T-S模糊模型描述的非线性系统,采用状态反馈的并行分布补偿方法研究其非脆弱保性能模糊控制问题,使得在控制器存在可加性摄动的情况下,其闭环性能指标值低于确定的上界。利用线性矩阵不等式处理方法,导出了非脆弱保性能模糊控制律的存在条件。通过建立和求解一个凸优化问题,给出了最优非脆弱保性能模糊控制律的设计方法,并用此方法设计一级倒立摆的非脆弱模糊控制律。仿真结果表明了方法的有效性。     

一种时滞相关非脆弱模糊控制器的设计

研究了一类带有时变时滞的离散模糊双线性系统的时滞相关非脆弱控制问题。引入自由权值矩阵并定义一种新型的Lyapunov函数,在控制器存在加性不确定的情况下,得到了保守性小的时滞相关渐近稳定的充分条件。通过附加矩阵,将所得到的稳定条件转换为线性矩阵不等式(linear matrix inequality, LMI)形式,非脆弱控制器可由LMI的解得到。数例仿真验证了该方法的有效性。     

Non-fragile guaranteed cost control for uncertain neutral large-scale interconnected systems

This paper focuses on the problem of non-fragile decentralized guaranteed cost control for uncertain neutral large-scale interconnected systems with time-varying delays in state, control input and interconnections. A novel scheme, viewing the interconnections with time-varying delays as effective information but not disturbances, is developed. Based on Lyapunov stability theory, using various techniques of decomposing and magnifying matrices, a design method of the non-fragile decentralized guaranteed cost controller for unperturbed neutral large-scale interconnected systems is proposed and the guaranteed cost is presented. The further results are derived for the uncertain case from the criterion of unperturbed neutral large-scale interconnected systems. Finally, an illustrative example shows that the results are significantly better than the existing results in the literatures.     

Guaranteed cost control for discrete-time networked control systems with random Markov delays

The guaranteed cost control for a class of uncertain discrete-time networked control systems with random delays is addressed.The sensor-to-controller (S-C) and contraller-to-actuator (C-A) random network-induced delays are modeled as two Markov chains.The focus is on the design of a two-mode-dependent guaranteed cost controller,which depends on both the current S-C delay and the most recently available C-A delay.The resulting closed-loop systems are special jump linear systems.Sufficient conditions for existence of guaranteed cost controller and an upper bound of cost function are established based on stochastic Lyapunov-Krasovakii functions and linear matrix inequality (LMI) approach.A simulation example illustrates the effectiveness of the proposed method.     

不确定非线性广义系统的鲁棒控制与保性能控制

研究了不确定非线性结构扰动的广义系统的鲁棒控制和保性能控制问题,该不确定性为时间、状态函数且满足Lipschitz条件的。目的是分别设计系统的鲁棒控制器和保性能控制器。应用线性矩阵不等式方法,分别给出了系统的鲁棒控制器和保性能控制器存在的充分条件;并在这些条件可解时,分别给出了鲁棒控制器和保性能控制器的表达式。最后用例子说明了所给方法的应用。     

Static output feedback control for discrete-time fuzzy bilinear system

The problem of designing fuzzy static output feedback controller for T-S discrete-time fuzzy bilinear system (DFBS) is presented.Based on parallel distribution compensation method,some sufficient conditions are derived to guarantee the stability of the overall fuzzy system.The stabilization conditions are further formulated into linear matrix inequality (LMI) so that the desired controller can be easily obtained by using the Matlab LMI toolbox.In comparison with the existing results,the drawbacks,such as coordinate transformation,same output matrices,have been eliminated.Finally,a simulation example shows that the approach is effective.     

精馏塔极小极大鲁棒非脆弱控制的研究

将极小极大控制器的设计应用于精馏塔模型。考虑系统和控制器同时含有不确定性,利用线性矩阵不等式(LMI)处理方法和Lyapunov稳定性理论,设计了鲁棒且非脆弱的极小极大控制器。考虑不确定性对系统破坏最大的情形,分别给出含有加性和乘性干扰增益的控制器存在条件。引入凸优化算法,求解使闭环系统渐近稳定且性能指标上界最小的最优控制器参数。仿真结果表明所设计的控制器具有良好的鲁棒性和非脆弱性。     

Decentralized robust guaranteed cost control for a class of interconnected singular large-scale systems with time-delay and parameter uncertainty

The decentralized robust guaranteed cost control problem is studied for a class of interconnected singular large-scale systems with time-delay and norm-bounded time-invariant parameter uncertainty under a given quadratic cost performance function. The problem that is addressed in this study is to design a decentralized robust guaranteed cost state feedback controller such that the closed-loop system is not only regular, impulse-free and stable, but also guarantees an adequate level of performance for all admissible uncertainties. A sufficient condition for the existence of the decentralized robust guaranteed cost state feedback controllers is proposed in terms of a linear matrix inequality (LMI) via LMI approach. When this condition is feasible, the desired state feedback decentralized robust guaranteed cost controller gain matrices can be obtained. Finally, an illustrative example is provided to demonstrate the effectiveness of the proposed approach.     

一类非线性系统的有限时间保成本控制

针对一类具有有限能量外部扰动的连续不确定非线性系统,讨论其有限时间保成本控制问题。首先采用Takagi-Sugeno模糊模型对非线性系统进行建模,然后找到一个合适的Lyapunov函数,给出闭环模糊系统有限时间有界的充分条件及有限时间保成本控制器的设计方法,并将控制器的求解转化为一组线性矩阵不等式的可行性问题。研究表明,采用该方法设计的控制器不仅能使闭环不确定模糊系统对所有可允许的外部扰动是有限时间有界的,而且还给出了保成本上界的一个优化值。最后,仿真结果表明该设计方法是有效的。     

Guaranteed cost control with constructing switching law of uncertain discrete-time switched systems

A guaranteed cost control problem for a class of linear discrete-time switched systems with norm-bounded uncertainties is considered in this article. The purpose is to construct a switching rule and design a state feedback control law, such that, the closed-loop system is asymptotically stable and the closed-loop cost function value is not more than a specified upper bound for all admissible uncertainties under the constructed switching rule. A sufficient condition for the existence of guaranteed cost controllers and switching rules is derived based on the Lyapunov theory together with the linear matrix inequality (LMI) approach. Furthermore, a convex optimization problem with LMI constraints is formulated to select the suboptimal guaranteed cost controller. A numerical example demonstrates the validity of the proposed design approach.     

广义双线性系统的变结构控制

利用广义Lyapunov函数方法研究广义双线性系统的变结构控制问题.首先,考虑确定的广义双线性系统,通过引进滑动模动态补偿器来选取切换面,进而设计变结构控制器以保证闭环系统的渐近稳定性.其次,用类似的方法给出了不确定广义双线性系统的变结构控制设计,有效地解决了不确定广义双线性系统的变结构控制问题.最后,通过数值算例说明了设计方法的合理性和有效性.     

不确定广义系统的弹性保性能控制

将弹性控制器的设计思想引入到一类不确定广义系统中,利用线性矩阵不等式(LMI)方法,研究被控对象与控制器同时存在摄动的弹性保性能控制问题。针对控制器存在加法式摄动情形,以线性矩阵不等式约束条件给出了广义系统弹性保性能的充要条件,并以线性矩阵不等式的可行解给出了相应的控制器设计方法,通过求解具有线性矩阵不等式约束的凸优化问题,给出了性能上界最小意义下弹性控制器的设计。数值仿真表明了该设计方法的可行性。     

不确定时滞系统的指数稳定保代价可靠控制

针对一类含有时变时滞的不确定参数系统,研究了在执行器发生故障情况下系统指数稳定保代价可靠控制器设计问题。系统的性能函数是含有指数项和故障输入项的积分二次型函数。经过适当的状态变换,将原系统的指数稳定保代价可靠控制问题转化为另一个等价系统的保代价可靠控制问题。根据Lyapunov稳定性理论,得到了系统存在指数稳定保代价可靠控制器应满足的一个矩阵不等式,进一步将这个矩阵不等式转化为线性矩阵不等式(LMI),并给出了系统的保代价表达式。利用论文方法设计的控制器能够使得时滞系统对于任意允许的不确定量以及执行器故障都保持鲁棒可靠指数稳定,并且使系统具有保代价的性能指标。仿真结果表明了该控制器设计方法的有效性。     

Non-fragile decentralized H∞ controller design for uncertain linear systems

Considering the design problem of non-fragile decentralized H∞ controller with gain variations, the dynamic feedback controller by measurement feedback for uncertain linear systems is constructed and studied. The parameter uncertainties are considered to be unknown but norm bounded. The design procedures are investigated in terms of positive definite solutions to modify algebraic Riccati inequalities. Using information exchange among local controllers, the designed non-fragile decentralized H∞ controllers guarantee that the uncertain closed-loop linear systems are stable and with H∞ -norm bound on disturbance attenuation. A sufficient condition that there are such non-fragile H∞ controllers is obtained by algebraic Riccati inequalities. The approaches to solve modified algebraic Riccati inequalities are carried out preliminarily. Finally, a numerical example to show the validity of the proposed approach is given.     

不确定广义系统的保成本可靠控制

对一类含有时变范数有界参数不确定广义系统和部分执行器可能失效的系统,结合一个二次型性能指标,研究了使得闭环系统保持正则、无脉冲和稳定,且闭环性能指标值不超过某个确定界的保成本可靠控制律的设计问题。通过矩阵不等式导出保成本可靠控制律的一个充分存在条件,进而用线性矩阵不等式给出了保成本可靠控制器的一个参数化的表示。在此基础上,通过建立并求解一个凸优化问题,给出了最优保成本可靠控制律的设计方法。最后,通过例子对所得结论加以说明。     

非线性扰动离散广义时滞系统的鲁棒H∞控制

研究了扰动是满足Lipschitz条件的一类非线性离散广义时滞系统的鲁棒H_∞控制和鲁棒H_∞保性能控制问题。目的是设计系统的鲁棒H_∞控制器和鲁棒H_∞保性能控制器。应用线性矩阵不等式方法,分别给出了系统的鲁棒H_∞控制器和鲁棒H_∞保性能控制器存在的充分条件;并在这些条件可解时,分别给出了鲁棒H_∞控制器和鲁棒H_∞保性能控制器的表达式。最后用例子说明了所给方法的应用。     

Reference tracking control for flexible air-breathing hypersonic vehicle with actuator delay and uncertainty

This paper considers the problem of reference tracking control for the flexible air-breathing hypersonic flight vehicle with actuator delay and uncertainty.By constructing the Lyapunov functional including the lower and upper bounds of the time-varying delay,the non-fragile controller is designed such that the resulting closed-loop system is asymptotically stable and satisfies a prescribed performance cost index.The simulation results are given to show the effectiveness of the proposed control method,which is validated by excellent output reference altitude and velocity tracking performance.     

Robust reliable guaranteed cost control for nonlinear singular stochastic systems with time delay

To study the design problem of robust reliable guaranteed cost controller for nonlinear singular stochastic systems, the Takagi-Sugeno （T-S） fuzzy model is used to represent a nonlinear singular stochastic system with norm-bounded parameter uncertainties and time delay. Based on the linear matrix inequality （LMI） techniques and stability theory of stochastic differential equations, a stochastic Lyapunov function method is adopted to design a state feedback fuzzy controller. The resulting closed-loop fuzzy system is robustly reliable stochastically stable, and the corresponding quadratic cost function is guaranteed to be no more than a certain upper bound for all admissible uncertainties, as well as different actuator fault cases. A sufficient condition of existence and design method of robust reliable guaranteed cost controller is presented. Finally, a numerical simulation is given to illustrate the effectiveness of the proposed method.     

具有控制约束的不确定离散时滞系统最优保性能控制

对一类具有范数有界时变参数不确定性和控制输入约束的离散时滞系统,研究其最优保性能状态反馈控制律的设计问题.基于线性矩阵不等式处理方法,导出了保性能控制律存在的条件,并证明了该条件等价于一组线性矩阵不等式的可行性问题,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.进而,通过建立并求解一个凸优化问题,给出了具有控制约束的最优保性能控制律设计方法.