一类非最小相位非线性系统的直接自适应控制

一类非最小相位非线性系统的直接自适应控制韩存武,袁少强,马晓军,文传源（北京航空航天大学自控系北京１０００８３）关键词：非线性系统,自适应控制,非最小相位系统．１引言非线性系统的自适应控制作为当前自动控制领域最富有挑战性、同时也最困难的前沿课题之一越...     

一类非线性非最小相位系统的直接自适应控制

针对一类不确定的离散时间非线性非最小相位动态系统,提出了一种基于神经网络和多模型的直接自适应控制方法．该控制方法由线性直接自适应控制器,神经网络非线性直接自适应控制器以及切换机构组成．线性控制器用来保证闭环系统输入输出信号有界,非线性控制器用来改善系统性能．切换策略通过对上述两种控制器的切换,保证闭环系统输入输出有界的同时,改善了系统性能．理论分析以及仿真结果表明了所提出的直接自适应控制方法的有效性．     

一类非最小相位非线性系统的神经网络自适应控制策略

针对一类非最小相位非线性系统，基于线性化和前馈补偿的思想，提出了神经自适应控制算法。得到了前馈控制律的闭环稳定性分析，并给出仿真结果。     

非线性非最小相位系统的控制研究综述

非线性非最小相位系统是指具有不稳定零动态或内部动态的非线性系统, 其本身固有的非最小相位特性限制了许多常规非线性控制方法(如反推控制、反馈线性化、滑模控制等)的直接应用. 因此, 非最小相位系统的控制比最小相位系统要困难得多, 是控制理论与工程应用中具有挑战性的课题之一. 本文综述了目前非线性非最小相位系统的研究成果, 着重介绍了非最小相位系统的成因、特性、 理想内模求解等问题, 并对其镇定、轨迹跟踪及路径跟踪等控制方法进行了分析比较. 最后, 讨论了非线性非最小相位系统研究领域中尚存在的问题, 并对其未来发展方向进行了展望.     

一类非最小相位多变量系统的自适应控制设计

利用一种有界输入计算方法,根据对象的左互质分解（ＬＣＦ） 特性,对一类多变量离散时间模型跟踪控制系统（ ＭＦＣＳ） 进行设计,进而给出相应的非最小相位系统自适应控制器的设计方法。     

一类MISO 最小相位系统的执行器故障自适应容错控制

针对一类具有执行器卡死或/和变执行器故障的多输入单输出(MISO)非线性最小相位系统,提出一种自适应容错跟踪控制方案.采用自适应算法估计系统的不确定性,利用神经网络逼近执行器未知故障函数,以完成执行器组合故障状态下的跟踪控制.所设计的控制律不仅保证了闭环系统稳定,而且所有状态均有界,跟踪误差一致最终有界.仿真结果表明了所提出方法的有效性.     

非最小相位FIR系统的自适应辨识

提出了一种基于线性代数方程组约束和梯度法的非最小相位FIR系统的自适应辨识算法.选用的线性方程组具有列满秩的系数矩阵,保证了系统参数的唯一可识别性.由于只采用高阶累量,故能够抑制任何高斯有色噪声的影响.重点讨论了梯度法中步长的选择,提出了收敛速度最快的变步长.仿真实验的结果证实了算法的有效性.     

非最小相位非线性系统的简单递归神经网络控制(英文)

从简单递归神经网络的统一结构出发设计了简单递归神经网络控制器,在引入了控制加权的目标函数下优化神经网络权值学习,因此是通常意义的神经网络控制的推广。证明了整个系统的稳定性,并通过仿真验证了控制器的有效性。     

基于非线性PID的非最小相位系统控制

提出一种新型非线性PID控制器简单结构，利用非线性PID控制器的非线性特性，抑制非最小相位系统的右半平面零点所造成的负调问题，克服非最小相位系统的超凋、负调和调整时间之间的矛盾。数值仿真结果表明，由非线性PID控制器构成的非最小相位系统具有良好的动静态性能、高的控制精度和较强的鲁棒性。数值结果说明方法有效，算法简单，易于实时实现。     

一类非线性随机系统的自适应控制

本文在文献「１,２」的基础上,对一类仿射非线性随机系统的最小二乘（ＬＳ）自适应控制问题进行了分析,给出了稳定性及收敛速度结果,在这里,我们仅要求非线性函数具有线性增长速度,而无需任何其它结构假设。     

Iterative Learning Control With Advanced Output Data

In this paper, iterative learning control using output data, which are more advanced than the relative degree of the system, is being investigated. It is known that the output error can be made zero with the conventional iterative learning control in which the input is updated with the output data advanced by the relative degree. However, the input can become too large for nonminimum phase systems. With the proposed scheme, the input can be prevented from becoming unnecessarily too large, which in turn makes it practical to apply iterative learning control for nonminimum phase systems. Simulations are performed to show the effectiveness of the scheme.     

Stable redesign of predictive control

The paper deals with I/O versions of receding horizon controllers based on the minimization of multistep quadratic costs with the constraint that the terminal state goes to zero. The resulting control law yields stable closed-loop systems under sharp conditions. Simulation results are presented to both verify the theoretical analysis and relate the new control law with GPC     

非最小相位系统跟踪控制综述

非最小相位系统是指包含不稳定零动态的系统.经典的跟踪控制理论,特别是非线性系统跟踪控制理论,是以最小相位系统为基础建立的,不能直接用于非最小相位系统.研究非最小相位系统跟踪控制理论,是对经典控制理论的扩展和补充,具有重要的意义.本文对目前非最小相位系统跟踪控制领域取得的成果进行综述.首先梳理各种非最小相位系统跟踪控制方法的基本思想,并按照近似跟踪和精确跟踪进行归类,建立非最小相位系统跟踪控制的基本框架.然后围绕该框架对各种方法进行详细介绍.接着讨论非最小相位系统的跟踪性能限制.最后总结现有研究存在的一些问题及对今后的发展方向进行展望.本文的目的在于使控制工作者对非最小相位系统的跟踪控制有一个较为清晰的认识.     

Observation and output adaptive tracking for a class of nonlinear non-minimum phase systems

ABSTRACT

In this paper, the output tracking problem for a class of systems with unstable zero dynamics is addressed. The state is assumed not measurable. The output of the dynamical system to be controlled has to track a signal, which is the sum of a known number of sinusoids with unknown frequencies, amplitudes and phases. The non-minimum phase nature of the considered systems prevents the direct tracking by standard sliding mode methods, which are known to generate unstable behaviours of the internal dynamics. The proposed method relies on the availability of a flat output and its time derivatives which are functions of the unavailable state; therefore, a nonlinear observer is needed. Due to the uncertainty in the frequencies and in the parameters defining the relationship between the output of the system and the flat states, adaptive indirect methods are applied.     

具有间隙非线性系统的控制加权自适应控制

本文对具有间隙的非线性系统提出一种可控制开环不稳定及非最小相位系统的控制加权自适应算法,并给出了稳定性收敛性定理及其证明。仿真结果表明,该算法可明显地改善系统的控制性能。     

Nonlinear model-state feedback control for nonminimum-phase processes

A general nonlinear controller design methodology for continuous-time nonminimum-phase systems is presented, which utilizes synthetic outputs that are statically equivalent to the original process outputs and make the system minimum-phase. A systematic procedure is proposed for the construction of statically equivalent outputs with prescribed transmission zeros. The calculated outputs are used to construct a model-state feedback controller. The proposed method is applied to a nonminimum-phase chemical reactor control problem where a series/parallel reaction is taking place.     

Model algorithmic control (MAC); basic theoretical properties

A mathematical framework for the analysis of model algorithmic control is developed and the operations of the main components of the control structure are described. The single input-single output case is treated in detail and results pertaining to the stability and the robustness of such systems are derived, both for deterministic and stochastic (colored output additive noise) environment. The case of the nonminimum phase plant is also considered. The robustness problem is discussed and performance ‘measures’ of robustness are proposed. The results derived in this paper are more generally applicable to optimizing type of control laws. In particular, the paper establishes a close link between the stability and closed loop properties of optimizing type and feedback type of control laws.