广义分布参数系统的变结构控制

研究广义分布参数系统的控制综合问题，给出了直接控制形式和分布控制形式的变结构控制设计的方法，并结合例子说明了控制的设计过程。     

广义分布参数系统的变结构控制

研究广义分布参数系统的控制综合问题，给出了直接控制形式和分布控制形式的变结构控制设计的方法，并结合例子说明了控制的设计过程。     

电加热反应器温度的多变量广义开环解耦控制

多段电加热反应器的温度对象是一个存在着严重耦一听多变量，工且呈现一定非线性特性，因此，采用各回路单独调节方式很难对其进行快速，平稳和准确的控制。针对这一问题，本文设计了新型的多变量广义开环解耦控制器，并在小型反应装置上实施：结果表明该控制器控制效果好，容影印件实现并且具有较强的鲁棒性。     

PI型自抗扰广义预测控制的性能分析

为克服自抗扰控制(active disturbance rejection control, ADRC)算法在大时滞系统中的局限性,减小PI型广义预测控制(PI-type generalized predictive control, PI-GPC)算法的在线计算量,我们在先前的研究中提出了PI型自抗扰广义预测控制(PI-type active disturbance rejection generalized predictive control, PI-ADRGPC)算法。本文通过频域分析方法,对PI-ADRGPC算法进行了稳定性分析,利用PI-ADRGPC算法离散形式的开环传递函数绘制其伯德图,分析了参数变化对PI-ADRGPC性能的影响。通过绘制奈奎斯特曲线,分析了PI-ADRGPC算法的稳定性。通过控制一阶惯性环节以及船舶航向控制系统验证了所提出算法的性能。研究结果表明:与ADRC-GPC算法相比,PI-ADRGPC算法的响应速度更快、控制效果更好。     

管式聚合反应温度分布控制方法的研究

该文利用B样条神经网络建立了管式聚合反应温度分布函数的数学模型,为分布参数系统的建模提供了新方法。研究结果表明,神经网络的组合可以很好的解决分布函数这个高维数据集合的建模问题。该文以期望的温度分相与实测温度分布的误差集合为控制指标,通过最优化方法求解,得到了最优控制序列。以实验室聚合反应器为背景,对上述方法进行了仿真实验,并针对存在噪声和施加干扰的环境,提出了自适应的控制策略,获得了预期的研究结果。     

广义分布参数扰动系统滑动模态控制

研究广义分布参数扰动系统的变结构及其一致收敛问题。通过引入滑动模态补偿器,得到了简约型变结构控制的设计方法。最后研究了系统 的动态品质,并指正了个别文献中存在的错误。     

广义分布参数系统的初值问题

本文定义了广义左逆、广义Ｆｏｕｒｉｅｒ变换，矩产方根等概念，论述了由带奇异系数矩耦合偏微分方程描述的广义分布参数系统，由广义Ｆｕｒｉｅｒ变换定理讨论了广义分布参数系统的初值问题，得到了该系统的解及其相容的初值条件。     

分布参数系统的时空ARX建模及预测控制

本文针对一类可由抛物型偏微分方程描述的分布参数系统,研究了一种基于输入输出数据的建模与控制方法.首先利用Karhunen-Loève（K-L）分解提取系统的一组主导空间基函数,并以此对系统输出进行时空分解,随后由时空分解得到的时间系数部分以及系统激励构成输入输出信息,利用最小二乘法辨识出时域ARX模型,最后针对该模型设计了广义预测控制器.仿真结果表明,上述控制方法能够对分布参数系统取得良好的控制效果.     

基于Curve Fitting Toolbox反应器停留时间分布的确定

反应器停留时间分布的确定是建立反应器流动模型的基础。本文介绍了用MATLAB的Curve Fitting Toolbox计算反应器停留时间分布的方法。通过在图形界面下导入数据及平滑处理、采用平滑样条拟合数据以及数值积分等操作,确定了反应器停留时间分布的特征值,并且以确定系数R~2、误差平方和以及均方根误差评价拟合模型的精确度。研究表明:计算结果与文献相吻合。该法运行可靠,无需编程、易于掌握。与传统计算方法相比,操作更为便捷,强有力的图形界面也使计算变得更加简单而直观。     

基于广义预测PI的无刷直流电机速度控制研究

无刷直流电机(BLDCM,brushless DC motor)转速控制是电机控制中的重要问题之一.分析了无刷直流电机的工作原理,提出了广义预测优化PI的控制算法,采用数学模型对控制器的设计进行了理论推导.通过基于DSP的无刷直流电机实验平台进行广义预测PI控制算法实验验证,结果表明此控制算法能显著提高系统的性能,是有效可行的.     

Dynamic modeling and vibration control for a nonlinear 3‐dimensional flexible manipulator

In this paper, the control design and stability analysis are presented for a 3‐dimensional flexible manipulator system with input disturbances. To provide an accurate and concise representation of the manipulator's dynamic behavior, the flexible manipulator is described by a distributed parameter system with a set of partial differential equations and ordinary differential equations. Boundary control laws with disturbance observers are proposed to regulate orientation and suppress elastic vibrations simultaneously. The closed‐loop stability is achieved through rigorous analysis without any simplification of the dynamics based on the Lyapunov direct method. Numerical simulations demonstrate the effectiveness of the proposed scheme.     

比例–积分控制加广义预测控制算法及其应用

针对比例–积分(proportional-integral, PI)控制因不能预测未来输出而提前改变控制量使其用于光电稳定伺服系统时往往响应剧烈的问题,研究了光电稳定伺服系统的广义预测控制(generalized predictive control, GPC).首先通过证明受控自回归积分滑动平均(controlled auto-regressive integral moving-average, CARIMA)模型的直接递推预测与Diophantine方程预测等价,提出了预测较快的模型等价预测GPC算法,其预测复杂度比原GPC降低了一个阶次.其次通过对PI和GPC的特点进行分析,综合考虑两者的优缺点,提出了一种新型的基于PI增量和GPC增量加权的比例积分控制加广义预测控制(proportional-integral control plus generalized predictive control, PI+GPC)算法,实现了基于历史、当前和未来偏差计算控制量,并给出了算法设计流程和参数选取规则.最后通过仿真并在某光电稳定伺服平台上验证后得出, PI+GPC和PI相比稳定精度有所提高,且平稳性和快速性大为改善.     

Adaptive local tracking of a temperature profile in tubular reactor with partial measurements

In this work, a local constrained adaptive output feedback is presented for a class of exothermic tubular reactors models described by a nonlinear partial differential equations. The considered output is the measured temperature in a fixed zone of the reactor to regulate the temperature throughout the reactor to a ball with radius λ (arbitrarily small) centered at the fixed temperature profile. For a given measurement zone with length given in terms of the desired profile and λ and for initial temperature in a fixed domain, it is shown that the tracking error through the reactor tends asymptotically to a ball of arbitrary prescribed radius λ > 0, centered at the given temperature profile. Numerical simulations have been performed to illustrate the performance of the proposed approach.     

Iterative learning control of heat-up phase for a batch polymerization reactor

This paper describes a novel method for heat-up phase control of an industrial batch polymerization reactor where heat transfer characteristics change with batches due to fouling of the polymer products on the reactor wall. The main objective of the control is to settle the reactor temperature on a target value within ± 0.1°C in a minimum possible time. To achieve this goal utilizing the repetitive nature of batch operation, the control problem was defined as a tracking problem and feedback-assisted iterative learning control (FBALC) was employed as the underlying control technique. The proposed control method was applied to an industrial batch reactor polymerizing ABS resin. After on-site evaluation for an extended period of time, it was found that the proposed method gives a pronounced improvement in heat-up phase operation. Consistent heat-up profiles with a minimized settling time are obtained.     

高带宽无线局域网中PI速率控制算法

针对传统传输控制协议（TCP）在高带宽、无线网络中性能表现不佳的问题, 建立了一个端到端的虚拟路由器模型, 提出了一个端到端的发送端比例积分（PI）速率控制算法。根据RTT的变化, 利用PI控制器计算发送端的发送速率, 使瓶颈节点的队长稳定在一个目标位置, 减少拥塞丢包, 避免无线链路错误丢包引起的对拥塞窗口的错误调整。仿真结果表明, 与传统拥塞控制协议相比, 新机制能较好地控制路由器队长、提高网络负载的稳定性和网络吞吐率。     

Model predictive control for continuous lactide ring‐opening polymerization processes

Polylactic acid (PLA) is an attractive environment‐friendly thermoplastic that is bio‐sourced and biodegradable. PLA is industrially produced by the ring‐opening polymerization of lactide. This reaction is sensitive to drifts in the operating conditions and impurities in the raw materials that may affect the reaction rate as well as the polymer properties, which can be very costly in continuous processes. It is therefore crucial to employ a control strategy that allows recovering the nominal conditions and maintaining the desired properties and conversion level in case of drift. Three control strategies are discussed in this paper: proportional‐integral (PI) controller, dynamic optimization, and model predictive control (MPC). The proposed approaches are validated by simulation of a continuous PLA process constituted of three cascade reactors including one loop reactor in the middle. Besides the coupling of inputs and outputs, the process model is highly nonlinear, and the control is done only on the boundaries. The results show that the open‐loop optimization strategy provides better performance compared to the PI controller if the disturbance is assumed to be measured. The MPC also shows superior performances provided that the disturbance is first estimated. A polynomial model is developed to predict the nonmeasured disturbance based on the measured outputs.     

PI控制作用在催化反应模型时变中的应用*

非线性系统最显著的多态特性往往受到操作条件的限制而不可能在开环系统中充分地被揭示,PI控制器的控制增益将增加了闭环系统调节的自由度,以此所揭示的非线性行为为模型识别提供了有力的依据,本文提供了全局分析的计算方法,并以催化反应模型来说明方法的应用。     

预测PI时滞网络拥塞控制算法设计及性能分析

针对网络中存在的大时滞给主动队列管理算法性能带来的不利影响,将Sm ith预估器与Dahlin算法相结合,提出了一种预测PI拥塞控制算法,首先利用Sm ith预估器补偿时延滞后,克服了大时滞给系统性能带来的影响;然后按Dahlin算法设计控制器,把控制器参数和预估对象模型参数相结合,既减少了整定参数,也避免了参数整定时的相互影响.同时,利用经典控制理论方法分析了系统稳定性和存在链路容量干扰时瓶颈队列的暂态、稳态特性.仿真结果显示预测PI算法控制性能优于RED,PI算法及具有较强的鲁棒性.     

On the use of observability measures for sensor location in tubular reactor

In this paper we discuss the choice of sensor positions for a tubular reactor with a preset number of sensors. Different observability measures, based on the observability matrix (Kailath, Linear Systems, Prentice Hall, Englewood Cliffs, NJ, 1980; Callier and Desoer, Linear System Theory, Springer-Verlag, Berlin, 1991: Damak et al., DYCORD '92, 1992, pp. 315–320), the observability gramian (Callier and Desoer, 1991) as well as on the Popov-Belevitch-Hautus rank test (Kailath. 1980) will be considered for locating optimal sensor positions. The analysis is carried out on the reduced finite-dimensional model of the process. The results of these investigations will be illustrated in simulation and put in perspective with the modal observability properties of the original infinite-dimensional model.