共查询到20条相似文献，搜索用时 0 毫秒
1.
Denis Efimov Alexander Fradkov 《International Journal of Adaptive Control and Signal Processing》2015,29(6):765-782
The development of adaptive observer techniques for nonlinear systems in the output canonical form is proposed applying additional impulsive feedback in the observer equations. The stability of new impulsive adaptive observer is investigated. It is shown that under some conditions, the proposed impulsive feedback can improve the rate of the observer convergence or relax the requirement on persistency of excitation, which is usually introduced to ensure convergence of the parameter estimates. The proposed feasibility conditions include positivity of dwell time (boundedness of impulse frequency) and solvability of some Lyapunov‐like matrix inequalities. The results are illustrated by simulation for three examples (including a single link flexible joint robot example). Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
2.
Girish Chowdhary Tansel Yucelen Maximillian Mühlegg Eric N. Johnson 《International Journal of Adaptive Control and Signal Processing》2013,27(4):280-301
Concurrent learning adaptive controllers, which use recorded and current data concurrently for adaptation, are developed for model reference adaptive control of uncertain linear dynamical systems. We show that a verifiable condition on the linear independence of the recorded data is sufficient to guarantee global exponential stability. We use this fact to develop exponentially decaying bounds on the tracking error and weight error, and estimate upper bounds on the control signal. These results allow the development of adaptive controllers that ensure good tracking without relying on high adaptation gains, and can be designed to avoid actuator saturation. Simulations and hardware experiments show improved performance. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Daniela J. López‐Araujo Arturo Zavala‐Río Víctor Santibáñez Fernando Reyes 《International Journal of Adaptive Control and Signal Processing》2015,29(2):180-200
In this work, a generalized adaptive scheme for the global motion control of robot manipulators with constrained inputs is proposed. It gives rise to various families of bounded adaptive controllers defined through a general class of saturation functions. Compared with adaptive tracking control algorithms previously developed in a bounded input context, the proposed adaptive approach guarantees the motion control objective for any initial condition, avoiding discontinuities throughout the scheme, preventing the inputs to reach their natural saturation bounds, and permitting innovation on the saturating structure through its generalized form, giving a wide range of possibilities for performance improvement. Experimental results corroborate the efficiency of the proposed scheme. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
4.
Patrizio Tomei Cristiano Maria Verrelli 《International Journal of Adaptive Control and Signal Processing》2016,30(4):608-633
We show how the design of repetitive learning controls, which typically require perfect knowledge of the period T characterizing the periodic reference signals to be tracked, can be generalized, through the design of novel recursive add‐on period identifiers, to face sufficiently small period uncertainties in synchronization problems. Exponential period identification is achieved so that the asymptotic convergence properties guaranteed by the classical learning controls are preserved. Simulation results concerning multi‐link robot synchronization tasks are included. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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A. Yu. Pogromsky A. S. Matveev 《International Journal of Adaptive Control and Signal Processing》2017,31(1):138-144
The paper presents a novel approach to justification of asymptotic stability of linear time‐varying systems with persistently excited right‐hand side. This approach combines the direct Lyapunov method with the Steklov averaging technique; its distinguishing feature is closed‐form construction of the Lyapunov functional, along with resultant explicit estimates of the rate of convergency. © 2016 The Authors. International Journal of Adaptive Control and Signal Processing published by John Wiley & Sons, Ltd. © 2016 The Authors. International Journal of Adaptive Control and Signal Processing published by John Wiley & Sons, Ltd. 相似文献
6.
Brian Driessen Nader Sadegh Kwan Kwok 《International Journal of Adaptive Control and Signal Processing》2017,31(3):417-428
In this paper, we consider the design problem of making the convergence of the bounded‐input, multi‐input iterative learning controller presented in our previous work robust to errors in the model‐based value of the input‐output Jacobian matrix via a minimax (min‐max or 'minimize the worst case') approach. We propose to minimize the worst case (largest) value of the infinity‐norm of the matrix whose norm being less then unity implies convergence of the controller. This matrix is the one associated with monotonicity of a sequence of input error norms. The input‐output Jacobian uncertainty is taken to be an additive linear one. Theorem 3.1 and its proof show that the worst‐case infinity‐norm is actually minimized by choosing either the inverse of the centroid of the set of possible input‐output Jacobians or a zero matrix. And an explicit expression is given for both the criteria used to choose between the two matrices and the resulting minimum worst‐case infinity norm. We showed previously that the matrix norm condition associated with monotonicity of a sequence of output‐error norms is not sufficient to assure convergence of the bounded‐input controller. The importance of knowing which norm condition is the relevant one is demonstrated by showing that the set of minimizers of the minimax problem formulated with the wrong norm does not contain in general minimizers of the maximum relevant norm and moreover can lead to a gain matrix that destroys the assured convergence of the bounded‐input controller given in previous work. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
7.
Sayan Basu Roy Shubhendu Bhasin 《International Journal of Adaptive Control and Signal Processing》2019,33(12):1759-1774
This paper is a generalization of the recently developed techniques of initial excitation (IE)–based adaptive control with an introduction to the definition of semi‐initial excitation (semi‐IE), a still more relaxed notion than IE. Classical adaptive controllers typically ensure Lyapunov stability of the extended error dynamics (tracking error + parameter estimation error) and asymptotic tracking, while requiring a stringent condition of persistence of excitation (PE) for parameter convergence. Of late, the authors have proposed a new adaptive control architecture, which guarantees parameter convergence under the online‐verifiable IE condition leading to exponential stability of the extended error dynamics. In earlier works, it has been established that the IE condition is significantly milder than the classical PE condition. The current work further slackens the excitation condition by proposing the concept of semi‐IE. The proposed adaptive controller is proved to ensure convergence of the parameter estimation error to a lower‐dimensional manifold under the weaker semi‐IE condition, while the stronger condition of IE guarantees convergence of the parameter estimation error to zero. The designed algorithm is shown to improve transient response of tracking error sufficiently in contrast to conventional adaptive controllers. 相似文献
8.
一种实用的FUZZY自适应励磁控制方法 总被引：7，自引：1，他引：7
在线性最优质磁控制的基础上,通过引入一个ＦＵＺＺＹ推理机,提出了一种ＦＵＺＺＹ自适应励磁控制方法。由于ＦＵＺＺＹ推理机能根据发电机的实测功率和电压不断地修正控制器的反馈增益,因此,所提出的ＦＵＺＺＹ自适应励磁控制器能跟踪电力系统运行工况。数字仿真结果表明：ＦＵＺＺＹ自适应励磁控制器具有良好的控制性能。 相似文献
9.
基于模型参考方法的感应电机磁链的自适应观测及参数辨识 总被引：12，自引：0，他引：12
提出一种基于模型参考方法的自适应定子磁链观测器,这种观测器不必预先知道电机的任何参数值,并且因运行时电机参数发生改变而发生的观测偏差也是收敛的.当电机的激励电压满足所谓"充分激励"的条件时,还可以同时作为参数辨识器;即使输入电压不满足充分激励的条件,但如果部分参数已知,仍然可以辨识其余的参数.仿真和实验结果验证了该方法的正确性. 相似文献
10.
Craig J. Lalumiere Daniel E. Miller 《International Journal of Adaptive Control and Signal Processing》2024,38(6):1975-1998
Supervisory control has been shown to be a very effective approach to adaptive control which ensures step-tracking, exponential stability, and a degree of robustness to unmodeled dynamics. Here we apply the technique to the classical
11.
M. Reza J. Harandi Hamid D. Taghirad 《International Journal of Adaptive Control and Signal Processing》2021,35(12):2487-2498
Interconnection and damping assignment passivity-based control (IDA-PBC) provides a general framework to stabilize underactuated mechanical systems by assigning the desired Hamiltonian to the system, which is obtained from the solution of partial differential equations. In this article, the IDA-PBC method is applied to an underactuated cable-driven robot to stabilize out-of-plane motion of the system. An adaptation law for the system's mass is designed such that asymptotic stability is ensured with positive tension in cables through the direct Lyapunov method. The results are verified through some simulations. 相似文献
12.
针对目前同步电动机负载突变时,均采用强力磁的方式控制励磁电压,提出了一种基于神经网络的同步电动机过渡过程的控制,克服了以往采用强励磁方式使同步电动机强行拉回到同步运行状态而引起的系统超调过大的不利因素。在神经网络的训练过程中采用“理想加噪声”的训练方式,表明了神经网络具有良好的动态逼近能力和较高的可靠性;在负载变动比较大的情况下,给出了用神经网络控制同步电动机的过渡过程仿真曲线。仿真结果表明,神经网络励磁调节器对于运行状态或是系统参数变化阶段,均具有很好的自适应性,尤其对同步电动机突加负载时系统的超调和到达稳态的时间有了明显的改善。 相似文献
13.
同步发电机神经网络励磁控制的仿真研究 总被引：2，自引：1，他引：1
人工神经网络是试图模仿生物神经系统的功能而建立的一种智能信息处理系统,它具有许多优点适用于自动控制领域。本文应用神经网络的非线性映射能力,直接抽取表征发电机运行的状态量映射控制输入,针对所提出的模型比较了神经网络控制与PID控制的效果,证明了神经网络控制的优越性。 相似文献
14.
不确定性电力系统鲁棒自适应励磁控制 总被引：3，自引：0，他引：3
为降低电力系统不确定参数和外部干扰在建模和控制设计中对系统品质的影响,利用Backstepping方法,递归构造闭环系统耗散不等式的能量存储函数,进而得到具有干扰抑制的反馈控制.推证了存储函数又是Lyapunov函数,保证闭环系统渐进稳定.设计过程用估计值代替不确定参数,故系统对不确定参数具有适应能力.仿真结果表明,该... 相似文献
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Anton Glushchenko;Konstantin Lastochkin; 《International Journal of Adaptive Control and Signal Processing》2024,38(3):986-1016
A novel method of an adaptive linear quadratic (LQ) regulation of uncertain continuous linear time-invariant systems is proposed. Such an approach is based on the direct self-tuning regulators design framework and the exponentially stable adaptive control technique developed earlier by the authors. Unlike the known solutions, a procedure is proposed to obtain a non-overparametrized regression equation (RE) with respect to the unknown controller parameters from an initial RE of the LQ-based reference tracking control system. On the basis of such result, an adaptive law is proposed, which under mild regressor finite excitation condition provides monotonous convergence of the LQ-controller parameters to an adjustable set of their true values, which bound is defined only by the machine precision. Using the Lyapunov-based analysis, it is proved that the mentioned law guarantees the exponential stability of the closed-loop adaptive optimal control system. The simulation examples are provided to validate the theoretical contributions. 相似文献
18.
电力系统非线性鲁棒自适应分散励磁控制设计 总被引：15，自引：3，他引：15
利用反步法设计了多机电力系统中的非线性鲁棒自适应励磁控制方案,控制目标是调节发电机功角和频率至稳态运行点的极小领域,并使闭环系统对发电机阻尼系数和电抗参数的不确定性具有自适应能力,且对模型误差和外部有界干扰具备鲁棒性,同时保证各控制器是分散化和本地化的。采用4机系统进行的数字仿真结果表明,实施此方案能有效地提高发电机的功角稳定性。 相似文献
19.
Changchun Hua Xinping Guan Peng Shi 《International Journal of Adaptive Control and Signal Processing》2005,19(7):531-545
The problem of robust stabilization for uncertain dynamic time‐delay systems is considered. Firstly a class of time‐delay systems with uncertainties bounded by high‐order polynomials and unknown coefficients are considered. The corresponding controller is designed by employing adaptive method. It is shown that the controller designed can render the closed‐loop system uniformly ultimately bounded stable based on Lyapunov–Krasovskii method and Lyapunov stability theory. Then the proposed adaptive idea is applied to stabilizing a class of large‐scale time‐delay systems with strong interconnections. A decentralized feedback adaptive controller is designed which guarantees the closed‐loop large‐scale systems uniformly ultimately bounded stable. Finally, numerical examples are given to show the potential of the proposed techniques. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
20.
Daniel E. Miller Mohamad T. Shahab 《International Journal of Adaptive Control and Signal Processing》2021,35(6):965-990
Classical discrete-time adaptive controllers typically provide asymptotic stabilization and tracking; usually the affect of the noise is at best bounded-input bounded-output. Recently we have shown that if you design a discrete-time adaptive controller in just the right way, then in a variety of situations you not only obtain exponential stability, but also a bounded gain on the noise in every p−norm, as well as a never-before-seen linear-like convolution bound on the input–output behavior. Quite surprisingly, the approach is very natural, and relies on the use of the unmodified, original projection algorithm to carry out parameter estimation; if the set of plant uncertainty is not convex, then a multi-estimator and switching are used. The goal of this paper is to provide an overview of the approach, discuss the results-to-date, and list some of the open problems. 相似文献