自整定PID控制器的现状和展望

本文是讨论PID控制器参数自整定的方法。着重讨论了用于单输入单输出对象PID控制器的改进型Ziegler-Nichols自整定方法和以人工智能为基础的专家系统自整定的方法。     

电加热系统最优PID参数自整定控制方法

电加热杆抽油作为一种有效的开采稠油的方法,具有设备简单、操作方便、加热效果好、成本低等一系列优点。针对电加热系统,提出了加热对象的数学模型;通过仿真实验对两种不同最优准则下进行了比较研究,得出时间平方加权的误差平方积分(ISTTE)准则下的控制方法,仿真结果表明该方法可以缩短系统的调节时间,有效地抑制系统的超调,从而为提高稠油电加热系统的加热效率提供了一种参考。     

具有最优指标的PID参数自整定系统

在分析研究各种过程参数辨识和PID整定方法的基础上,提出了以误差积分准则为最优性能指标的一种PID参数自整定方法。这种方法的要点是仅采用几个特征量,就能比较准确地在线测算过程特性参数,引入采样时间Ts作为附加参数,修改Lopez公式系数;以修改系数后的Lopez公式作为PID参数预整定的关系式;在预整定基础上进行适当修改,使控制系统达到最佳状态。数字仿真和实时控制表明,这是一种较好的实用的自整定方法,适用于相当广泛的一类过程对象。     

基于LONWORKS现场总线的自整定PID控制系统

将ＰＩＤ自整定技术和现场总线技术有机地结合起来,实现了基于ＬＯＮＷＯＲＫＳ现场总线的ＰＩＤ自整定系统。自整定系统由两层组成,上层为ＰＣ计算机,下层为一个智能节点。它们之间通过ＬＯＮＷＯＲＫＳ现场总线进行通信。ＰＣ计算机给操作人员提供一个良好的人机界面,同地控制着整个ＰＩＤ参数自整定的过程。实验证明了该自整定系统的适用性和有效性,必将在工业过程控制中得到广泛的应用。     

模糊自整定PID控制器的设计与仿真

制浆碱回收蒸发工段第一步就是通过蒸汽将黑液进行浓缩,蒸汽的温度控制效果对后续燃烧工段和苛化工段起着举足轻重的作用。主管道蒸汽温度控制通常具有大惯性、大延迟、时变等特性,采用常规的PID控制难以获得满意的控制效果。为此,提出一种模糊自整定PID控制器的串级控制算法,该算法很大程度上提高了主蒸汽温度的控制品质。针对隶属度函数对模糊推理模型的精度影响和控制算法的特点编写了模糊规则,并且根据动态性要求的不同,分两种情况进行比较。仿真表明,模糊自整定PID串级控制算法在整体性能上要优于传统PID串级控制。     

工业自整定PID调节器关键设计技术综述

对十年来国内外在工业过程控制中使用的自整定PID调节的设计方法与关键技术进行了全面综述和评价,这对我国进行同类高科技自动化仪表的开发研制及商品化有重要的指导意义.     

模式识别法PID参数自整定

本文研究了用模式识别法进行PID参数自整定。分析确定了一类模式的状态变量,利用这组变量获取过程模型,从而可以利用离线优化得到的各种整定规则进行自整定。仿真结果表明,这是一种简单实用的PID自整定方法。     

一种PID自整定温度控制器及实现

根据瑞典学者Ｋ．Ｊ．Ａｓｔｒｏｍ提出在继电反馈下观察被控过程的极限环振荡,自动整定ＰＩＤ控制器参数,并针对一类电阻炉的温度控制在ＩＰＣ－６１０工控机上予以实现,给出了控制电路、控制策略及程序流程图。自整定实时控制结果表明,该算法容易在工业控制机上实现。     

基于模糊自整定PID的永磁同步电机矢量控制

为克服传统的PID矢量控制系统存在响应速度慢及抗干扰能力差等缺点,提出基于模糊自整定PID的永磁同步电机矢量控制系统,并通过Matlab对传统PID和模糊自整定PID的控制效果进行对比,充分验证了该控制方法的可靠性和有效性。     

基于传递函数估计的闭环PID参数自整定

基于对被控对象传递函数的估计,提出一种闭环PID参数整定方法.通过实时采集被控对象的输入输出数据,采用平均相关系数法估计被控对象的传递函数.然后采用时域受限二次型目标函数寻优PID参数.最后用工业应用实例,说明该方法的有效性.     

基于幅频裕度配置PID自整定软件的设计和实现

基于继电辨识及相位、幅值裕度的理论,提出一种基于幅频裕度配置PID参数自整定方法,并按照相应理论完整设计了软件.利用继电辨识得到过程的临界振荡点,选择不同的相位裕度和幅值裕度得到不同的PID参数组,并提供相应的预期阶跃响应曲线帮助参数选择.另外基于DCS系统平台设计了自整定软件包,现场应用灵活.     

Low-gain internal model control PID controller design based on second-order filter

A design method is proposed for low-gain internal model control (IMC) proportional-integral-derivative (PID) controllers based on the second-order filter. The PID parameters are obtained by approximating the feedback form of the IMC controller with a Maclaurin series, in which the second-order filter is applied using the IMC approach to achieve a low-gain PID controller that is suitable for model mismatch problems. Analytical PID tuning rules based on the second-order filter are derived for several common-use process models. The second-order filter is designed from the desired time domain performances of maximum overshoot and settling time. Furthermore, the robustness of the IMC PID controller based on the second-order filter is analyzed, and results show that its robustness performance is better than the first-order filter under certain conditions. Finally, three categories of models divided by the ration of time constant and time delay are presented in the comparative numerical simulations to validate the effectiveness and generality of the proposed PID controller design method.     

Self-tuning PID controllers based on the Lyapunov approach

In this paper, a self-tuning PID controller using just-in-time learning (JITL) technique is proposed. A set of linear models obtained by the JITL provides the information required to adjust the parameters of PID controller. The self-tuning algorithm for the PID parameters is derived by a rigorous analysis based on the Lyapunov method such that the JITL's predicted tracking error converges asymptotically. Simulation results are presented to illustrate the proposed self-tuning PID controller and a comparison with its conventional counterparts is made.     

基于变结构参数自整定模糊PID的节能控制系统

设计基于变结构参数自整定模糊PID和空气源热泵的节能控制系统,分析模糊运算规则,实现风量温度的高精度控制。用力控组态软件对整个节能控制系统进行组态。实际生产运行结果表明:该系统的节能效果明显,操作界面友好。     

模糊自整定PID控制方案在自动加药系统中的应用

在选矿工艺中,加药过程是影响选矿品质的重要因素,传统浮选加药主要采用人工加药或定量加药方式,其缺点是误差大、效率低和成本高。因此,提出一种模糊自整定PID控制方案,对加药过程进行自动控制。投产后,运行稳定,效果良好。     

Robust PID controller design for nonlinear processes using JITL technique

A robust PID controller design methodology for nonlinear processes is proposed based on the just-in-time learning (JITL) technique. To do so, a composite model consisting of a nominal ARX model and the JITL, where the former is used to capture linear process dynamics and the latter to approximate the inevitable modeling error caused by the process nonlinearity, is employed to model the process dynamics in the operating space of interest. The state space realizations of this composite model and PID controller are then reformulated as an uncertain closed-loop system, by which the corresponding robust stability condition is developed. Literature examples are employed to illustrate the proposed methodology and a comparison with the previous result is made.     

New results on VRFT design of PID controller

Virtual reference feedback tuning (VRFT) design method can be applied to determine the parameters of a PID controller from the available process input and output data without resorting to the identification of a process model. Although it is an attractive alternative to the popular model-based controller design methods, the existing results are restricted to the linear systems. In this paper, an adaptive VRFT design method with application to the adaptive PID controller design is proposed. In addition, the relationship between the VRFT and IMC designs is analyzed as well. Simulation results are presented to illustrate the advantage of the adaptive VRFT design over the conventional VRFT design.     

基于期望响应的预测函数控制参考轨迹自校正方法

采用指数律参考轨迹的传统预测函数控制（PFC）,系统动态响应无法预先估计,不能直接按照指定的轨迹整定动态响应。本文提出了一种预测函数控制参考轨迹自校正策略。基于事先规定的期望响应,对指数律参考轨迹的衰减系数进行实时在线滚动优化,保证预测时域内的参考轨迹最大幅度地贴近期望轨迹,使得系统响应能够准确地跟踪期望轨迹,并在指定的时刻到达设定值,同时也保留了控制输出平滑的特性。仿真实验证实了该方法的有效性及其优点。