Networked Predictive Control Systems Based on the Hammerstein Model

In this paper, a novel predictive control-based approach is proposed for a networked control system with random delays containing an input nonlinear process based on a Hammerstein model. The method uses a time-delay two-step generalized predictive control scheme, which consists of two parts: one is to deal with the input nonlinearity of the Hammerstein model and the other is to compensate for the network-induced delay in the networked control system. A theoretical result using the Popov criterion is presented for the closed-loop stability of the system in the case of a constant delay. Simulation examples illustrating the validity of the approach are also presented.     

Multirate Event-Triggered MPC for NCSs with Transmission Delays

This paper investigates the event-triggered model predictive control problem for networked control systems with transmission delays. Based on a multirate scheme, an event-triggered delay compensation strategy is proposed. The event-triggered predictive control algorithm with feasibility and stability guarantee is built upon the triggered conditions that determine whether the measurements are transmitted. The results are further extended to a self-triggered mechanism to avoid continuous monitoring of measurements difference. Finally, simulation results are given to illustrate the effectiveness of the proposed methods.     

Networked Predictive Control of Systems With Random Network Delays in Both Forward and Feedback Channels

The design problem of networked control systems (NCS) with constant and random network delay in the forward and feedback channels, respectively, is considered in this paper. A novel networked predictive control (NPC) scheme is proposed to overcome the effects of network delay and data dropout. Stability criteria of closed-loop NPC systems are presented. The necessary and sufficient conditions for the stability of closed-loop NCS with constant time delay are given. Furthermore, it is shown that a closed-loop NPC system with bounded random network delay is stable if its corresponding switched system is stable. Both simulation study and practical experiments show the effectiveness of the control scheme     

Design and Stability Criteria of Networked Predictive Control Systems With Random Network Delay in the Feedback Channel

This paper is concerned with the design of networked control systems (NCSs) with random network delay in the feedback channel and gives stability criteria of closed-loop networked predictive control systems. The principle of predictive control is adopted to overcome the effects of network time delay. The necessary and sufficient conditions on the stability of the closed-loop NCS are derived, which provides useful analytical stability criteria. The closed-loop networked predictive control system with bounded random network delay is stable if the corresponding switched system is stable. Simulation and real-time results give an illustration of the proposed control strategies     

一种高性能网络化控制器的硬件设计

目前,网络化控制的研究大部分还只是停留在控制系统的稳定性研究、控制算法的研究等理论上的探讨。在这样的背景下,提出一款基于嵌入式技术的高性能网络化控制器的硬件设计方法,并给出基于该网络化控制器的倒立摆网络化控制实验。在实验中,倒立摆的摆杆在垂直位置小范围内来回振动,并达到稳定状态。实验效果证明了该网络化控制器在处理控制运算算法和网络通信方面有着优异的性能。该控制器已被成功应用于实验室。     

网络化控制模型的设计

文章首先介绍了网络化控制技术模型装置的设计,分别阐述了控制实验模型的整体设计和以太网控制系统的设计.上层监控软件采用LabVIEW图形化开发环境设计.然后针对参数整定过程中出现的困难,提出了将神经网络模糊PID自整定技术应用到该系统中的方案.该模型装置包含了工程应用中许多控制参数,可以满足不同程度的仿真实验和研究需要.     

网络化控制技术模型装置的设计研究

介绍了网络化控制技术模型装置的设计,分别阐述了控制实验模型的整体设计以及现场总线控制系统和以太网控制系统的设计。上层监控软件基于LabVIEW图形化开发环境。提出了用神经网络模糊PID自整定技术解决控制系统参数整定的问题的方案。     

基于可行解及移动闭塞策略的新型逆变电路模型预测控制

电力电子电路是典型的混杂系统,文章建立了一种新型容错逆变电路的混杂系统模型,与开关函数模型相比,电路混杂系统模型能更好地描述电路的动态过程,有助于实现电路的精确控制.在此基础之上,将可行解及移动闭塞的思想用于电路的MPC,以电路可行解代替最优解,可有效减少电路控制序列总数、降低开关频率,实现电路MPC的快速求解,仿真和实验验证了控制方法的可行性与有效性.     

动态泛回归神经网络预测的研究与仿真

在HUATECA3000过程控制实验系统上选取实验对象,研究了三容水箱液位非线性控制系统,提出了一种动态泛回归神经网络预测控制算法.先后通过开环与闭环控制,搭建了SIMUUNK仿真模型研究算法的有效性.仿真结果表明闭环预测控制改进了系统在干扰作用下的稳态和动态性能.     

基于虚拟仪器技术的传感器实验的探索

以“传感器”实验为切入点,介绍电子类课程实验利用虚拟仪器技术搭建实验平台和软件设计。其中包括利用虚拟仪器技术开发的传感器实验、电子电路实验和仿真实验的操作界面。实验分为虚实结合实验和虚拟仿真实验。该平台具有数据自动采集、数据存储、数据处理、快速绘制曲线、实验报告自动生成、点击即可发送邮件等功能。利用平台进行了光纤传感器实验、频率特性实验和PID直流电机控速实验,结果表明：实验自动化、无纸化,网络化,打造了“以学生为中心”的教学平台,让学生有更多时间自主学习；实验资源网络化,实验报告规范化,解决了昂贵的实验资源不足的问题,提升了实验老师的工作效率。     

New Predictive Control Scheme for Networked Control Systems

This paper is concerned with the design of networked control systems with random network-induced delay and data dropout. It presents a new control scheme, which is termed networked predictive control with optimal estimation. Based on Multirate Kalman Filtering, the measured data which are out of sequence or delayed can be used to improve the precision of estimation. The control prediction generator provides a set of future control predictions to make the closed-loop system achieve the desired control performance and the compensator removes the effects of the network transmission with time delay and data dropout. Simulation results are presented to illustrate the effectiveness of the control strategy via comparing with control schemes without any compensation for the network.     

网络化试验测试系统框架设计技术研究

分析了网络化试验测试系统当前的技术现状,根据当前存在的设备搭建与布置问题、通信信息与带宽问题、设备实时监控调试问题提出了通过网络化技术解决试验测试需求的系统构架,提出了网络化试验测试的解决路径.     

基于遗传算法的制冷系统动态矩阵控制

根据数据采用最小二乘法辨识得到制冷系统多变量传递函数模型,随后对制冷系统设计动态矩阵控制器,使系统蒸发温度和过热度在满足约束条件下达到控制要求;考虑到DMC控制器的控制时域、预测时域、控制量权重矩阵等参数直接影响系统的稳定性和输出跟踪效果,而一般试凑法选取参数不可避免地存在主观性和随机性,因此给出一种基于遗传算法的DMC参数寻优方法,并应用于制冷系统的控制问题中。最后的仿真试验表明了算法的有效性。     

基于操作路径的物理实验考试评判系统的设计与实现

基于组件的计算机仿真实验的物理实验考试、评判系统通过对实验过程各单个状态评判初步实现了物理实验操作考核的自动评判[1,2]。在此基础上,本文提出了基于实验操作路径的评判模型和相应的动态规划算法-最高分拓扑路径匹配算法。通过连续记录实验过程关键实验状态,生成学生操作路径与相应的最高分拓扑路径匹配算法结果相比较,对实验关键状态连续整体自动评判,扩展物理实验考试系统自动评判范围。文章以双臂电桥测量低电阻实验为例,实现了对学生实验操作关键状态整体的自动评判。     

基于GPC-PID的制冷系统过热度控制器

针对制冷系统的过热度控制问题,为保证系统动态性能,给出了一种基于广义预测控制滚动优化策略的PID参数自调整算法,设计了GPC-PID控制器.首先根据试验数据,基于最小二乘方法辨识得到过热度与膨胀阀开度间的传递函数模型,随后考虑系统模型的纯滞后环节,基于广义预测控制的性能指标,根据Kuhn-Tucker条件,通过滚动优化策略自动整定PID控制器的参数.最后的仿真结果表明,与传统PID控制器相比,GPC-PID控制器超调小,响应速度快,具有较好的控制效果.     

时间序列预报法在供热控制中的应用研究

为了节能和优质供热,提出将负荷预报和预测控制施加于供热系统中.文中首先介绍了时间序列法预报原理,接着应用该原理给出供热负荷和模型误差的预报.负荷预报作为供热系统的设定值,模型误差作为预测控制的校正量.最后,给出了两种预报方法在供热系统的应用及仿真结果.     

基于工业模型的新型PID实验系统设计

基于Matlab仿真的传统PID实验系统,不仅缺少实际控制对象,且存在一定的抽象性。为了完善该系统,设计实现了一种基于工业模型的新型PID实验系统。该系统在原有仿真实验的基础上,增加了工业电机控制模型,并以LPC2114为核心处理器,L298N为电机驱动的直流电机控制系统,通过Matlab编程进行PID实时控制。实验证明,该系统不仅保留了Matlab仿真实验的准确性,更能体现出PID参数变化对系统的影响,展现了PID的工业控制效果,提高PID实验系统的直观性。     

Robotic Office Room to support office work by human behavior understanding function with networked machines

This paper proposes a novel human-robot symbiosis system named a Robotic Office Room (ROR). The understanding, recording and retrieving of telephone call behavior are successfully demonstrated as a typical example of an office work-supporting function of ROR. A unique object model is proposed, which accumulates information concerning motion of the object. This model enables the system to understand human behavior, not by monitoring the motion of the human, but by monitoring the motion of the object-typically, a telephone or pen. Since the model requires the system to pay spatial and temporal attention only to the target object and related motions, it saves computing power. Repertoires of understandable behavior can easily be expanded by simply adding new object models. The ROR is equipped with networked machines. The concept of "ubiquitous link" consisting of unique image channels and remote control channels is proposed. The image channel and the remote control channel utilize TV images and either ultrasonic waves or infrared rays, respectively. Such cooperative support of humans by networked machines is realized that when a human starts to talk on the phone, the ROR not only starts to record the image of the human's behavior, utilizing a VCR, but also turns down the volume on an audio set. The experiment proved the feasibility of the ROR as an integrated robotic system to support human office work.     

具有时延和丢包的不确定性NCS的稳定性

研究了同时具有网络时延和数据丢包的不确定网络化控制系统的稳定性.将数据丢失看成一种特殊的时延,利用动态反馈控制器设计提高系统的动态性能,得到了总时滞(包括传感器与控制器之间的时滞,控制器与执行器之间的时滞)的表达式,建立了不确定网络化控制系统模型.通过构造李亚普诺夫函数,采用线性矩阵不等式技巧,给出了系统稳定的判定定理.仿真结果表明了该方法的有效性.