基于调节/观测时间的自抗扰控制器参数整定

受带宽自抗扰控制器(ADRC)参数整定方法启发,给出一种基于系统调节时间/观测时间的ADRC参数整定方法.利用调节时间与控制器带宽之间的关系,给出基于调节时间整定非线性控制器参数$k_p$及$k_d$的方法;同时,利用所定义的观测时间概念,给出一种扩张状态观测器(ESO)参数整定策略.这两种ADRC参数整定方法简化了基于带宽方法的参数整定过程,拓展了其应用范围.仿真结果表明了所提出方法的有效性.     

基于改进遗传算法的自抗扰控制器参数优化

本文将一种改进的遗传算法应用到自抗扰控制器（ADRC）的参数整定中,以解决ADRC 参数不易整 定的问题．在ADRC 参数优化过程中建立了控制器控制效果目标评价函数,在函数中综合考虑了控制器的动态性能 和被控对象的输入受限条件．所设计的ADRC 控制器所需的控制能量明显小于其他方法所设计的ARDC 所需控制 能量．仿真结果表明,本文所提ADRC 参数整定方法是有效的．     

基于时间尺度的感应电机自抗扰控制器的参数整定

自抗扰控制器(ADRC)在感应电机控制中取得了优良的控制效果, 但控制器参数整定比较困难. 本文从时间尺度的概念入手分析ADRC参数整定问题, 通过理论分析得出感应电机的时间尺度, 并结合时间尺度与ADRC参数的关系进行参数整定, 得到了感应电机按定子磁场定向矢量控制的ADRC控制器参数整定方法, 该方法尤其适于多台电机的参数整定. 仿真结果表明该方法可行, 为感应电机ADRC提供了一种参数整定方法.     

根据系统时间尺度整定自抗扰控制器参数

自抗扰控制器(ADRC)取得了优良的控制效果, 但控制器参数整定比较困难. 本文利用受控系统时间尺度展开ADRC参数整定问题的研究. 首先, 在时间尺度一般定义的基础上, 根据系统单位阶跃响应, 给出了二阶系统的时间尺度计算格式. 然后, 在被控对象受扩展状态器(ESO)补偿作用所得积分器串联系统的时间尺度不变的假设下, 推导了一种基于受控系统时间尺度的ADRC控制器参数整定方法. 最后, 仿真结果表明该方法可行, 为ADRC参数整定提供了方便.     

基于动态反馈控制器的网络控制系统的稳定性分析

考虑实际模型的不确定性,针对一类具有不确定线性参数的网络控制系统,给出具有网络诱导时延及不确定线性参数的被控对象模型,设计其动态反馈控制器,建立基于动态反馈控制器的网络控制系统闭环模型.采用Lyapunov方法,给出保证该系统稳定的最大允许时延上界.仿真结果表明系统模型及控制器设计的合理性,所得最大允许时延上界保守性更弱.     

基于弹性控制器的网络控制系统稳定性分析

研究了一类不确定网络控制系统的弹性控制器设计问题。针对一类具有不确定参数的被控对象模型,考虑网络诱导时延的作用,建立基于弹性反馈控制器的网络控制系统闭环模型。采用Lyapunov方法,给出保证该闭环系统稳定的允许时延上界。仿真结果证明了本文方法的正确性和有效性。     

带记忆比例–积分–时滞输出滑模控制器设计

传统的比例–积分–微分(PID)滑模控制具有高频测量噪声鲁棒性差、参数整定方法复杂等缺点. 针对上述问题, 本文设计了一种基于带记忆输出反馈的比例–积分–滞后(PIR)滑模控制器, 并提出了基于频域分析的控制器参数自整定方法. 在控制器选型上, 将“带记忆”反馈机制引入到滑模面设计中, 提高滑模面的平滑滤波和高频噪声抑制能力. 首先, 基于PIR滑模面设计了等效控制律, 实现输出反馈下的闭环系统的滑模态稳定. 其次, 分析了基于输出反馈的PIR滑模面的有限时间可达性, 确保系统在存在匹配扰动时仍保持良好的鲁棒性. 最后, 在控制器参数整定方面, 通过迭代消除法消去时滞项在闭环特征方程中的影响, 同时基于衰减速率对系统进行极点配置, 实现PIR参数的在线自整定. 仿真结果表明, 该整定方法能够保证闭环二阶系统具有良好的鲁棒性和抗干扰性能.     

基于RBF神经网络PID控制的无线网络时延控制研究

针对不确定时延影响无线网络控制系统的控制性能、常规PID控制策略无法满足网络控制要求的问题,提出了一种基于RBF神经网络PID控制的无线网络时延控制方案。采用Matlab/Simulink的TrueTime工具箱建立了无线网络时延控制系统仿真模型,介绍了模型中网络模块、执行器模块、控制器模块的设计及RBF神经网络整定PID控制器参数的实现原理。仿真结果表明,与常规PID控制策略相比,RBF神经网络PID控制策略能够在一定程度上降低不确定时延对无线网络控制系统的影响,从而提高无线网络控制系统的稳定性。     

基于改进差分算法的变桨ADRC参数优化

自抗扰控制器是一类不依赖被控对象数学模型且具有较强鲁棒性及抗干扰能力的非线性控制器,已成功应用于风力发电机变桨距控制这一多变量、强耦合的非线性系统中,但自抗扰控制器也存在参数众多整定难度大这一明显缺点。现提出了通过智能算法来实现参数的自动整定。分析了改进差分进化算法的原理及步骤,并将改进差分进化算法应用到ADRC的整定过程中,实现参数的自动整定。仿真结果验证了通过改进差分进化算法自动整定ADRC参数的可行性,与传统PID控制器相比,改进差分进化算法整定后的ADRC能较好的满足风力发电机变桨控制要求,有效维持了风力发电机组输出功率的稳定性。     

动态矩阵控制在网络时延补偿中的应用研究

在网络控制系统中,随机传输时延大大降低了系统的控制性能,并导致系统的不稳定.针对以太网在网络控制系统中的随机传输时延问题,提出了一种基于DMC的NCS时延补偿控制方案.该方案采用DMC算法设计控制器,同时通过网络时延补偿器和动态缓冲器整定控制量,使系统输出能迅速跟踪突变输入.利用TureTime工具箱进行仿真实验,结果证明了该算法在处理网络控制系统的时延问题时具有有效性和可行性.     

Guaranteed cost control of distributed parameter networked control systems with time‐varying delay

Distributed parameter networked control systems mean distributed parameter systems are controlled through a network, where the control loops are closed. In this paper, the problem of guaranteed cost and state feedback controller design is investigated for a class of distributed parameter networked control systems. With the network factors, such as transmission delays, data packet dropouts considered, the distributed parameter networked control system is modeled as a linear closed‐loop system with time‐varying delay and uncertain parameters. By selecting an appropriate Lyapunov‐Krasovskii function and using linear matrix inequality (LMI) approach, the controller is designed to render the system stable and it can keep the cost function less than a certain upper value. In addition, numerical simulation is included to demonstrate the theoretical results.     

Prediction‐based Adaptive Robust Tracking Control of an Uncertain First‐Order Time‐Delay System

This paper considers the tracking problem of a delayed uncertain first‐order system which is simultaneously subject to (possibly large) known input delay, unknown but bounded time‐varying disturbance, and unknown plant parameter. The proposed predictor adaptive robust controller (PARC) involves prediction‐based projection type adaptation laws with model compensation and prediction‐based continuous robust feedback such that the closed loop system has global exponential convergence with an ultimate bound proportional to delay, disturbance bound, and switching gain. Further, if there are only delay and parameter uncertainties after some finite time, then semi‐global asymptotic tracking is guaranteed. The proposed design is shown to have significant closed loop performance improvement over the baseline controller.     

BIBO stability and stabilization of networked control systems with short time‐varying delays

This paper presents a robust control approach to solve the stability and stabilization problems for networked control systems (NCSs) with short time‐varying delays. A new discrete‐time linear uncertain system model is proposed to describe the NCS, and the uncertainty of the network‐induced delay is transformed into the uncertainty of the system matrix. Based on the obtained uncertain system model, a sufficient BIBO stability condition for the closed‐loop NCS is derived by applying the small gain theorem. The obtained stability condition establishes a quantitative relation between the BIBO stability of the closed‐loop NCS and two delay parameters, namely, the delay upper bound and the delay variation range bound. Moreover, design procedures for the state feedback stabilizing controllers are also presented. An illustrative example is provided to demonstrate the effectiveness of the proposed method. Copyright © 2010 John Wiley & Sons, Ltd.     

基于LMI方法的网络闭环控制系统离散鲁棒模糊控制

针对网络闭环控制系统中时延和不同步等不确定因素,将时延的不确定性转换为系统状态方程系数矩阵的不确定性,提出了一种新的网络闭环控制系统建模方法———具有时滞的不确定离散模糊T-S模型;并在此模型的基础上,利用并行分布补偿原理和Lyapunov理论及LMI方法,证明了通过状态的静态反馈模糊控制,使闭环系统稳定的充分条件等价于求解一组LMI。仿真示例验证了该控制方法的有效性.     

基于互联网的远程控制系统时延补偿的仿真研究

本文介绍了由西门子S7—226PLC与MM440变频器组成的电气控制系统在光缆护套机速度控制中的应用，并对该系统的控制原理作了详细的阐述。     

基于ARM的网络远程闭环控制机理研究与实现

针对网络远程控制的研究大部分还只是停留在开环控制或工业专用网络的问题,本文提出了一种基于Internet的远程闭环控制方案,根据该方案设计并实现了一个基于Internet的ARM网络远程控制器和本地控制器,在实验室搭建了网络远程闭环控制物理模拟实验平台,并在该平台上,针对大惯性水位控制对象和网络传输延时的不确定性问题,设计了一种基于在线信息排队的网络延时补偿方法,该方法克服了网络拥塞与不确定性延时对系统的影响,进行了网络远程闭环实时控制实验,得到了较好的控制效果。     

Robust exponential stability of uncertain stochastic systems with probabilistic time‐varying delays

This paper is concerned with the problem of delay‐distribution–dependent robust exponential stability for uncertain stochastic systems with probabilistic time‐varying delays. Firstly, inspired by a class of networked systems with quantization and packet losses, we study the stabilization problem for a class of network‐based uncertain stochastic systems with probabilistic time‐varying delays. Secondly, an equivalent model of the resulting closed‐loop network‐based uncertain stochastic system is constructed. Different from the previous works, the proposed equivalent system model enables the controller design of the network‐based uncertain stochastic systems to enjoy the advantage of probability distribution characteristic of packet losses. Thirdly, by applying the Lyapunov‐Krasovskii functional approach and the stochastic stability theory, delay‐distribution–dependent robust exponential mean‐square stability criteria are derived, and the sufficient conditions for the design of the delay‐distribution–dependent controller are then proposed to guarantee the stability of the resulting system. Finally, a case study is given to show the effectiveness of the results derived. Moreover, the allowable upper bound of consecutive packet losses will be larger in the case that the probability distribution characteristic of packet losses is taken into consideration.     

Anti‐windup design of active disturbance rejection control for sampled systems with input delay

A novel anti‐windup design of active disturbance rejection control (ADRC) is proposed for industrial sampled systems with input delay and saturation. By using a generalized predictor to estimate the delay‐free system output, a modified extended state observer is designed to simultaneously estimate the system state and disturbance, which could become an anti‐windup compensator when the input saturation occurs. Accordingly, a feedback controller is analytically designed for disturbance rejection. By proposing the desired closed‐loop transfer function for the set‐point tracking, a prefilter is designed to tune the tracking performance while guaranteeing no steady‐state output tracking error. A sufficient condition for the closed‐loop system stability is established with proof for practical application subject to the input delay variation. Illustrative examples from the literature are used to demonstrate the effectiveness and merit of the proposed control design.     

Analytical design of active disturbance rejection control for nonlinear uncertain systems with delay

For first-order nonlinear uncertain systems with delay, the analytical design of active disturbance rejection control (ADRC) with matched time delay is rigorously studied. The conditions of stabilizing the closed-loop system are studied in the form of parameters’ explicit sets such that the tuning laws of ADRC can be directly obtained and intuitively demonstrated in engineering practice. The necessary and sufficient condition of the asymptotical stability for the closed-loop system in the case of linear time-invariant is explicitly given. The condition of stabilizing the closed-loop system with nonlinear uncertain dynamics is quantitatively presented. Moreover, the water tank experiment illustrates the proposed tuning laws.     

Adaptive robust control of uncertain systems with state and input delay

In this paper, adaptive robust control of uncertain systems with multiple time delays in states and input is considered. It is assumed that the parameter uncertainties are time varying norm-bounded whose bounds are unknown but their functional properties are known. To overcome the effect of input delay on the closed loop system stability, new Lyapunov Krasovskii functional will be introduced. It is shown that the proposed adaptive robust controller guarantees globally uniformly exponentially convergence of all system solutions to a ball with any certain convergence rate. Moreover, if there is no disturbance in the system, asymptotic stability of the closed loop system will be established. The proposed design condition is formulated in terms of linear matrix inequality (LMI) which can be easily solved by LMI Toolbox in Matlab. Finally, an illustrative example is included to show the effectiveness of results developed in this paper.