一类非线性离散时间系统的神经网络解耦策略

考虑用神经网络作为补偿器,对一类非线性系统进行输入输出解耦.给出了这类系 统的可解耦的充要条件,并证明在该条件下系统可解耦成线性系统且极点可任意配置.基于 此,给出了这类系统的一个神经网络解耦方法.     

一类非线性奇异控制系统的块解耦

讨论了在正则状态下反馈作用下，一类非线性奇异控制系统的输入输出块解耦问题，首先给一种算法，然后利用该算法导出系统输入块解耦问题可解的充分必要条件。     

Disturbance localization and pole shifting by dynamic compensation

This paper concerns the problem of disturbance localization and pole shifting by dynamic compensation in multivariable linear systems with inaccessible state vector. A necessary and sufficient condition for the solvability of the problem is given. Two synthesis procedures of the compensator are presented: one is based on an observer and the other is based on a dual observer. The observer designed by the proposed procedure acts as as unknown input observer for a linear function. An improved procedure of designing a reduced order unknown input observer is also given. The result may be applicable to reducing the compensator order.     

Disturbance-rejection problems with low-order dynamic compensatorfor linear ω-periodic discrete-time systems

In this note, necessary and sufficient conditions for the solvability of the disturbance-rejection problem with dynamic compensator (DRPDC), which has a time-varying state dimension, are given for linear ω-periodic discrete-time systems without assuming that the order of dynamic compensator is equal to that of system plant. Further, the minimal order of dynamic compensator, which is necessary for the solution of the problem, is also investigated under the assumption that the disturbance map is independent of time k     

Nonlinear output regulation for invertible nonlinear MIMO systems

In this paper, we address the problem of output regulation for a broad class of multi‐input multi‐output (MIMO) nonlinear systems. Specifically, we consider input–affine systems, which are invertible and input–output linearizable. This class includes, as a trivial special case, the class of MIMO systems which possess a well‐defined vector relative degree. It is shown that if a system in this class is strongly minimum phase, in a sense specified in the paper, the problem of output regulation can be solved via partial‐state feedback or via (dynamic) output feedback. The result substantially broadens the class of nonlinear MIMO systems for which the problem in question is known to be possible. Copyright © 2015 John Wiley & Sons, Ltd.     

Sufficient and necessary conditions for the solvability of the state feedback regulation problem

In this paper, we discuss the state feedback output regulation problem (SFRP) for infinite‐dimensional linear control systems with infinite‐dimensional exosystems. Under the polynomial stabilizability assumption, sufficient and necessary conditions are given for the solvability of the SFRP. The solvability of this problem is characterized in terms of the solvability of a pair of linear regulator equations. An application of the solvability of the SFRP for polynomial stable SISO system is given. Copyright © 2013 John Wiley & Sons, Ltd.     

Global robust output regulation for a class of multivariable systems

In this paper, we study the global robust output regulation problem for a class of multivariable nonlinear systems. The problem is first converted into a stabilization problem of an augmented system composed of the original plant and an internal model. The augmented system is a multi‐input system containing both dynamic uncertainty and time‐varying static uncertainty. By decomposing the multi‐input control problem into several single‐input control problems, we will solve the problem by solving several single‐input control problems via a recursive approach utilizing the changing supply function technique. The theoretical result is applied to the speed tracking control and load torque disturbance rejection problem of a surface‐mounted permanent magnet synchronous motor. Copyright © 2011 John Wiley & Sons, Ltd.     

Singular nonlinear H∞ optimal control problem

The theory of nonlinear H_∞ of optimal control for affine nonlinear systems is extended to the more general context of singular H_∞ optimal control of nonlinear systems using ideas from the linear H_∞ theory. Our approach yields under certain assumptions a necessary and sufficient condition for solvability of the state feedback singular H_∞ control problem. The resulting state feedback is then used to construct a dynamic compensator solving the nonlinear output feedback H_∞ control problem by applying the certainty equivalence principle.     

Output feedback stabilization for delayed large‐scale stochastic systems with markovian jumping parameters

This paper deals with the problem of decentralized output feedback stabilization for a class of large‐scale stochastic time‐delay systems with Markovian jumping parameters. Attention is focused on the design of a decentralized dynamic output feedback controller, which is also with Markovian jumping parameters, such that the closed‐loop system is exponentially mean‐square stable. A sufficient condition for the solvability of this problem is proposed in terms of linear matrix inequalities. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

Non‐uniform in time robust global asymptotic output stability for discrete‐time systems

In this paper the notions of non‐uniform in time robust global asymptotic output stability (RGAOS) and input‐to‐output stability (IOS) for discrete‐time systems are studied. Characterizations as well as links between these notions are provided. Particularly, it is shown that a discrete‐time system with continuous dynamics satisfies the non‐uniform in time IOS property if and only if the corresponding unforced system is non‐uniformly in time RGAOS. Necessary and sufficient conditions for the solvability of the robust output feedback stabilization (ROFS) problem are also given. Copyright © 2005 John Wiley & Sons, Ltd.     

动态扰动解耦补偿器

本文利用极大绝对能观子系统及其对偶概念,对扰动解耦问题有解的充要条件给出了一个新的形式。对一类多输入多输出系统,给出了解耦补偿器的一般形式和稳定解耦的充要条件。     

A lattice approach to analysis and synthesis problems

Within a lattice approach, the purpose of this paper is to give general necessary and sufficient conditions for internal stabilizability and for the existence of (weakly) left-/right-/doubly coprime factorizations of multi input multi output linear systems. These results extend the ones recently obtained in [24] for single input single output systems. In particular, combining these results with the one obtained in [3, 13], we prove that every internally stabilizable multidimensional system admits doubly coprime factorizations, solving Lin's conjecture [17, 18].     

The nonlinear interactor and its application to input-outputdecoupling

The solvability of the input-output decoupling problem via pure dynamic state feedback, a special type of dynamic compensator without zeros at infinity, is investigated. A necessary and sufficient condition for the solvability of this problem is established in terms of a nonlinear interactor, a new concept in the theory of nonlinear control     

Gain scheduled control for discrete‐time systems depending on bounded rate parameters

In this paper we consider a linear, discrete‐time system depending multi‐affinely on uncertain, real time‐varying parameters. A new sufficient condition for the stability of this class of systems, in terms of a feasibility problem involving linear matrix inequalities (LMIs), is obtained under the hypothesis that a bound on the rate of variation of the parameters is known. This condition, obtained by the aid of parameter dependent Lyapunov functions, obviously turns out to be less restrictive than that one obtained via the classical quadratic stability (QS) approach, which guarantees stability in presence of arbitrary time‐varying parameters. An important point is that the methodology proposed in this paper may result in being less conservative than the classical QS approach even in the absence of an explicit bound on the parameters rate of variation. Concerning the synthesis context, the design of a gain scheduled compensator based on the above approach is also proposed. It is shown that, if a suitable LMI problem is feasible, the solution of such problem allows to design an output feedback gain scheduled dynamic compensator in a controller‐observer form stabilizing the class of systems which is dealt with. The stability conditions are then extended to take into account L₂ performance requirements. Some numerical examples are carried out to show the effectiveness and to investigate the computational burden required by the proposed approach. Copyright © 2005 John Wiley & Sons, Ltd.     

双线性系统的全局可镇定性

讨论了多输入多输出双线性系统的全局可镇定问题.利用Lyapunov方法,分别通 过静态状态反馈和动态输出反馈得到双线性系统全局可镇定的充分条件,并且给出了相应控 制器的设计方法.     

Block Decoupling by Precompensation Revisited

The block decoupling problem by admissible dynamic precompensation for LTI systems is considered. Admissibility refers to the preservation of the class of controlled output trajectories, i.e. functional output controllability is concerned, which is more demanding than just pointwise output controllability. This problem has been solved by Hautus and Heyman, within a transfer function matrix approach. Different new equivalent solvability conditions in terms of controllability subspaces, transfer function matrices or matrix pencils are given. One of these conditions (expressed in the input space) is at the origin of new necessary and sufficient conditions for block decoupling by general precompensation (possibly non admissible and nonsquare), in the wider sense of Basile and Marro     

Cooperative robust output regulation problem for discrete‐time linear time‐delay multi‐agent systems

In this paper, we study the cooperative robust output regulation problem for discrete‐time linear multi‐agent systems with both communication and input delays by a distributed internal model approach. We first introduce the distributed internal model for discrete‐time multi‐agent systems with both communication and input delays. Then, we define the so‐called auxiliary system and auxiliary augmented system. Finally, we solve our problem by showing, under some standard assumptions, that if a distributed state feedback control or a distributed output feedback control solves the robust output regulation problem of the auxiliary system, then the same control law solves the cooperative robust output regulation problem of the original multi‐agent systems.     

Input/Output Decoupling of Square Linear Systems by Dynamic Two‐Parameter Stabilizing Control

Analytical expressions of the free parameters of a two‐parameter stabilizing control (TPSC), solving an input/output (I/O) decoupling problem, are presented, and stability conditions are given. Multi‐input‐multi‐output (MIMO), proper, lumped and linear time invariant (LTI) systems are considered. These systems have stabilizable and detectable realizations. The separation principle is applied to design a dynamic output control in a controller‐observer feedback configuration. The I/O relation of the overall system is equivalent to a subsystem, in which the I/O decoupling problem has a solution. Also, if the state dimension of the plant is even, and is double the input dimension of the plant, then coprime factorizations of the plant used for the stabilizing controllers are proposed. The results are illustrated through an example.     

Transformation of Nonlinear MIMO Discrete‐Time Systems into the Extended Observer Form

The paper addresses the problem of transforming discrete‐time multi‐input multi‐output nonlinear state equations into the extended observer form, which, besides the inputs and outputs, also depends on a finite number of their past values. Necessary and sufficient conditions for the existence of the extended coordinate transformation are formulated in terms of differential one‐forms, associated with the input‐output equations, corresponding to the state equations. The difference between the single‐input single‐output and multi‐input multi‐output cases is described. The applicability of the conditions is illustrated by an example.