强时变时滞系统的鲁棒PID继电自整定控制技术

文章对于工业过程中常见的大时变时滞过程,提出了一种数字鲁棒PID控制器参数继电自整定控制策略和技术,应用这种整定方法整定的PID控制器,闭环不确定系统可具有大时变时滞鲁棒镇定性,且完全抑制负载干扰,具有很好的动静态性能,在造纸工业现场应用效果良好。     

基于模糊推理的自整定PID控制器

设计了一种新的模糊PID控制器，用基于给定的相角裕度和幅值裕度的方法给出了PID控制器参数的初值，在运行过程中，用模糊控制器在线调整PID参数，使过程具有较高的控制品质。     

聚丙稀反应过程鲁棒PID自整定系统的研究

针对聚丙稀反应过程的温度控制,提出了一种简单而鲁棒性较强的鲁棒PID控制算法．即将模型输出上下界和统计的方法,分别应用到聚丙稀反应过程带有滞后环节对象的鲁棒辨识中,再利用Minmax算法对稳定的PID控制器参数进行整定。最后使用UML建立了鲁棒PID控制器参数自整定系统的模型,对其进行了分析、设计和实现。实践表明:该系统能有效地控制聚丙稀反应过程的温度。     

一类工业过程的PID控制器整定方法

PID调节器具有结构简单、适应性强、不依赖于被控对象的精确模型、鲁棒性较强等优点。控制器的性能直接关系到生产过程的平稳高效运行以及产品的最终质量。针对一类可用带有纯时间延迟的一阶对象来近似描述的工业过程,本文通过对工业过程现场采集的数据,利用Levenberg-Marquardt最小二乘拟合法辨识出被控对象的数学模型,进而根据典型PID控制器的参数整定方法求出PID控制器的参数。通过对一个典型工业对象的仿真研究,结果表明所提出的方法简单有效。     

一种时滞过程内模PID控制器鲁棒整定方法

针对典型的一阶时滞（FOPTD）、二阶时滞（SOPTD）以及一阶时滞积分（FODI）过程,提出了一种简便的内模PID控制器设计和参数整定方法。 用一阶泰勒级数逼近系统模型的时滞项,导出内模PID控制器参数表达式,且仅有一个可调参数β,该可调参数与系统的动态性能和鲁棒性直接相关。基于控制系统的鲁棒性能指标给出了控制器可调参数β进行鲁棒整定的解析表达式。仿真结果表明,该方法可使系统同时获得良好的设定值跟踪特性、扰动抑制特性和克服参数变化的鲁棒性。        

基于频域辨识的自整定PID控制器

提出了一种引入继电反馈的自整定ＰＩＤ控制器,在线测出过程对象两点的频率特性,辨识出二阶纯滞后的模型,基于相位,幅值裕度整定出ＰＩＤ参数。还介绍了该方法适应范围,仿真实验及仿真结果。     

面向工业过程的鲁棒PID控制器设计

将内模控制原理和极小极大优化原则相结合,提出了一种新的鲁棒PID控制器设计方法.优化设计过程分步进行,综合采用多参数随机优化和解析优化方法.设计结果具有算法稳定、鲁棒性强、一致性好等特点,适合于工况变化频繁的工业过程回路控制.     

几种PID控制器参数整定方法的比较研究

本文以一阶惯性加时滞过程为研究对象，通过数字仿真和在实验室的物理对象进行的控制实验，研究了一些比较适合典型工业过程应用的PID整定方法的特点。本文选取了控制工程中常用的4：1衰减法、临界比例度法、鲁棒PID参数整定法和ISTE（Integral Squared Time-weighted Errors）最优参数整定法，从系统跟踪、抗干扰性能和鲁棒性方面进行了分析比较研究。数字仿真和物理对象的实时控制表明了这些方法有各自的优缺点，其中，鲁棒PID参数整定法和ISTE最优参数整定法在综合性能，特别是在系统的鲁棒性方面具有一定的优越性。本文的研究结果对于典型工业过程的PID控制器参数的整定有一定的借鉴作用。     

直流电动机的PID整定

传统PID控制器参数范围变化大,要调到想要控制的结果,工作量大,整定方法过于繁锁,PID参数的优化方法很多,本文采用基于实数编码遗传算法的PID整定方法,具有操作简单、整定速度快等很多优点。     

多变量PID控制器的在线自整定

本文研究具有ＰＩＤ结构反馈控制器的多变量控制系统的参数自整定，提出了具有校正因子的多变换ＰＩＤ控制算法及在线自动调整校正因子的专家自整定方法，将该方法用于火电单元机组负荷控制系统自整定仿真研究，结果表明系统具有好的完整性和鲁棒性。     

Integral criteria for optimal tuning of PI/PID controllers for integrating processes

Tuning formulas for PI/PID controllers for integrating processes are presented in this paper. The controller parameters are obtained by minimizing various integral performance index. Bacterial Foraging strategy, a new entrant to the family of evolutionary algorithms is used for minimization to avoid the local minima in the optimization procedure. A setpoint filter is used to reduce the large overshoot, and a significant improvement in control performance is obtained when compared to recently reported methods. Simulation results for an assumed perturbation in the plant delay are also given to illustrate the robustness of the proposed controller design method. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

A novel approach to monitoring and maintenance of industrial PID controllers

Due to process nonlinearities and operating condition changes, industrial processes frequently encounter significant dynamics variations, which would compromise the long-term effectiveness of controller monitoring schemes and leads to superfluous alarms. To address these issues, a novel performance benchmark based on the min-max principle is developed for industrial PID controllers, which has satisfactory applicability for nonlinear processes with operating condition switches. Furthermore, a holistic workflow of monitoring and maintenance of industrial PID controllers is proposed, including online identification of process models, poor control detection based on the accessible benchmark, and maintenance guides for poorly behaved controllers. Both simulation and industrial cases studies are presented to demonstrate the effectiveness of the proposed method.     

基于改进遗传算法的PID控制器设计

针对一般遗传算法存在的不足，提出一种改进的遗传算法，并将其应用于PID控制器参数设计。该方法采用实数编码，是为了操作方便、提高精度和收敛速度，且能克服传统PID参数整定的费时性。仿真结果表明，基于改进遗传算法设计的PID控制器获得了良好的控制效果，其控制性能优于常规的PID控制器。     

基于量子遗传算法的PID控制器参数自整定

提出了一种基于量子遗传算法（QGA）的PID控制器参数整定方法。首先定义一个包含表示系统超调量、上升时间和稳态误差指标项的适应度函数,并根据实际系统的性能要求对指标项进行适当加权。之后采用具有量子比特个体表示形式和量子旋转门实现种群进化的量子遗传算法,对PID进行多目标寻优,从而实现PID参数的自动整定。仿真结果表明,该方法优化得到PID控制器的综合性能优于常规方法和一般遗传算法得到的PID控制器。     

Interval-model-based global optimization framework for robust stability and performance of PID controllers

PID controller structure is regarded as a standard in the control-engineering community and is supported by a vast range of automation hardware. Therefore, PID controllers are widely used in industrial practice. However, the problem of tuning the controller parameters has to be tackled by the control engineer and this is often not dealt with in an optimal way, resulting in poor control performance and even compromised safety. The paper proposes a framework, which involves using an interval model for describing the uncertain or variable dynamics of the process. The framework employs a particle swarm optimization algorithm for obtaining the best performing PID controller with regard to several possible criteria, but at the same time taking into account the complementary sensitivity function constraints, which ensure robustness within the bounds of the uncertain parameters’ intervals. Hence, the presented approach enables a simple, computationally tractable and efficient constrained optimization solution for tuning the parameters of the controller, while considering the eventual gain, pole, zero and time-delay uncertainties defined using an interval model of the controlled process. The results provide good control performance while assuring stability within the prescribed uncertainty constraints. Furthermore, the controller performance is adequate only if the relative system perturbations are considered, as proposed in the paper. The proposed approach has been tested on various examples. The results suggest that it is a useful framework for obtaining adequate controller parameters, which ensure robust stability and favorable control performance of the closed-loop, even when considerable process uncertainties are expected.     

Relay auto-tuning of PID controllers using iterative feedback tuning

In this paper, ideas from iterative feedback tuning (IFT) are incorporated into relay auto-tuning of the proportional-plus-integral-plus-derivative (PID) controller. The PID controller is auto-tuned to give specified phase margin and bandwidth. Good tuning performance according to the specified bandwidth and phase margin can be obtained and the limitation of the standard relay auto-tuning technique using a version of Ziegler-Nichols formula can be eliminated. Furthermore, by using common modelling assumptions for the relay system, some of the required derivatives in the IFT algorithm can be derived analytically. The algorithm was tested in the laboratory on a coupled tank and good tuning result was demonstrated.     

佳点集遗传算法及其在PID控制中的应用*

传统遗传算法具有收敛速度慢、局部寻优能力较差且容易出现“早熟”等现象,运用数论中的佳点集理论与方法对其进行改进。改进的算法通过生成一种具有良好多样性的均匀初始种群,构造出新型的佳点交叉算子和变异算子,使得在进化过程中子代可以更好地继承父代的优良特性,有效地改善了传统算法的全局收敛速度,避免了“早熟”现象的发生。将此改进算法应用于工业PID控制器的参数寻优,仿真结果显示出佳点集遗传算法明显提高了搜索速度,系统的动态性能和稳定性也有明显改善。     

一类模糊P I D 控制器的鲁棒优化设计

研究一类模糊 PID控制器的鲁棒设计。以小增益定理分析得到该模糊 PID控制系统稳定性条件。针对参数摄动系统的“最坏点”,用该稳定性条件作为约束 ,采用遗传算法对标称系统的性能进行优化 ,求得优化鲁棒控制器。以倒立摆为例进行鲁棒模糊 PID控制器的设计 ,实验结果表明了该方法的有效性     

一种PID参数整定的粒子群优化算法

提出了一种PID控制器参数整定的粒子群优化算法。该方法首先通过定义一个包含系统超调量、上升时间和稳态误差指标项的适应度函数,并根据系统的实际控制要求对各指标项适当加权。之后由带收缩因子的粒子群算法对PID进行多目标寻优,从而实现PID控制器的自动参数整定。仿真结果表明,该方法优化得到PID控制器的综合性能优于常规方法得到的PID控制器。     

PID controller frequency-domain tuning for stable, integrating and unstable processes, including dead-time

In the present paper a new tuning procedure is proposed for the ideal PID controller in series with the first-order noise filter. It is based on the recently proposed extension of the Ziegler-Nichols frequency-domain dynamics characterization of a process G_p(s). Measured process characteristics are the ultimate frequency and ultimate gain, the angle of the tangent to the Nyquist curve of the process at the ultimate frequency, and G_p(0). For a large class of processes the same tuning formulae can be effectively applied to obtain closed-loop responses with predictable properties. Load disturbance step responses without the undershoot and reference step responses with negligible overshoot are obtained by analyzing a test batch consisting of stable, integrating and unstable processes, including dead-time and oscillatory dynamics. The proposed tuning makes possible to specify the desired sensitivity to the high frequency measurement noise and the desired maximum sensitivity. Comparison with the optimal ideal PID controller in series with the first-order noise filter is presented and discussed. The extension of the proposed method to the PI controller tuning is direct. Comparison with the optimal PI controller is presented and discussed.