Self-adaptive PID controller of microwave drying rotary device tuning on-line by genetic algorithms

The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and with multivariable nonlinear interaction of microwave and materials. The conventional PID control strategy incorporated with optimization GA was put forward to maintain the optimum drying temperature in order to keep the moisture content below 1%, whose adaptation ability included the cost function of optimization GA according to the output change. Simulations on five different industrial process models and practical temperature process control system for selenium-enriched slag drying intensively by using IMDRDWM were carried out systematically, indicating the reliability and effectiveness of control design. The parameters of proposed control design are all on-line implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed, which makes the developed scheme simpler in its synthesis and application, providing the practical guidelines for the control implementation and the parameter design.

Fuzzy self-tuning PID control of the operation temperatures in a two-staged membrane separation process

A two-staged membrane separation process for hydrogen recovery from refinery gases is introduced. The principle of the gas membrane separation process and the influence of the operation temperatures are analyzed. As the conventional PID controller is difficult to make the operation temperatures steady, a fuzzy self-tuning PID control algorithm is proposed. The application shows that the algorithm is effective, the operation temperatures of both stages can be controlled steadily, and the operation flexibility and adaptability of the hydrogen recovery unit are enhanced with safety. This study lays a foundation to optimize the control of the membrane separation process and thus ensure the membrane performance.

A Design of a PID Self-Tuning Controller Using LabVIEW

In this paper a trial has been made to design a simple self-tuning LabVIEW-based PID controller. The controller uses an open-loop relay test, calculates the tuned parameters in an open loop mode of operation before it updates controller parameters and runs the process as a closed-loop system. The controller reacts on a persistent offset error value as a result of load disturbance or a set point change. Practical results show that such a controller may be recommended to control a variety of industrial processes. A GUI was developed to facilitate control-mode selection, the setting of controller parameters, and the display of control system variables. GUI makes it possible to put the controller in manual or self-tuning mode.

Design and simulation about a self-Tuning fuzzy-PID controller

Fuzzy logic has attracted the attention of structural control engineers during the last few years,because fuzzy logic can handle nonlinearities,uncertainties,and heuristic knowledge effectively and easily.In this paper,a self-Tuning fuzzy-PID control method which used the technology of the fuzzy control and PID control unified is presented.These techniques can visualize the results and processes for structure stress.These techniques will also provide convenience for engineers and users,and have high practical values.The MATLAB simulation result shows that the system precision and the efficiency are very high and the static error is small,and robustness was also validated.

Development of an Enhanced Self-Tuning RBF-PID Controller for Achieving Higher Energy-Efficient Process Control

Proportional, integral and derivative (PID) control strategy has been widely applied in heating systems in decades. To improve the accuracy and the robustness of PID control, self-tuning radial-basis-function neural network PID (RBF-PID) is developed and used. Even though being popular, during the control process both of PID and RBF-PID control strategy are inadequate in achieving simultaneous high energy-efficiency and good control accuracy. To address this problem, in this paper we develop and report an enhanced self-tuning radial-basis-function neural network PID (e-RBF-PID) controller. To identify the superiority of e-RBF-PID, following works are conducted and reported in this paper. Firstly, four controllers, i.e., on-off, PID, RBF-PID and e-RBF-PID are designed. Secondly, in order to test the performance of the e-RBF-PID controller, an experimental water heating system is constructed for being controlled. Finally, the energy consumption for the four controllers under the three control scenarios is investigated through experiments. The experimental results indicate that in the three scenarios, the developed e-RBF-PID controller outperforms on-off controller as having higher accuracy. Compared to the PID controller, the e-RBF-PID controller has higher speed in control, and the experimental results show that settling time savings is between 12.6% - 49.0%. Most importantly, less control energy consumption is obtained if using the e-RBF-PID controller. It is found that up to 28.5% energy consumption can be saved. Therefore, it is concluded that the proposed e-RBF-PID is capable of enhancing energy efficiency during control process.

炼油化工装置PID性能评测与优化系统的设计与实现

根据对装置对象定义分区与KPI,并通过管理端和控制端2个工作平台进行集中、分散部署的方案设计思想,研究开发炼化装置PID性能评测与优化系统,为企业重点生产装置建立PID回路多尺度性能监测与预警、PID控制故障诊断与预知性维护、PID参数自动调优以及PID回路档案等功能应用。该系统能够实时监控PID性能KPI指标值,并智能推荐最优PID参数。试点装置应用效果的标定测试结果表明,PID系统的实际应用效果达到了技术设计指标,模型和算法的适用性、软件的成熟度得到了验证,具备在炼化装置中规模化扩展应用的条件,具有很好的推广应用价值。

SWISS整流器分数阶PID控制策略

针对SWISS整流器的传统整数阶PID控制策略动态响应速度较慢、鲁棒性较差的问题,提出一种基于分数阶PID的SWISS整流器控制策略。基于SWISS整流器的工作原理建立其小信号模型,得到SWISS整流器的等效传递函数,并设计基于分数阶PID电压控制的双闭环控制结构。为简化分数阶PID的阶次参数设计,采用整数阶PID参数预整定的方法得到参数初值,并利用粒子群算法对分数阶PID控制器参数进行进一步设计优化。仿真和实验结果表明,分数阶PID控制策略下的SWISS整流器发生参考电压突变时电压稳定时间小于7 ms、超调量小于2%,发生负载扰动时电压稳定时间小于4 ms、超调量小于3%,动态性能优于整数阶PID控制策略。

模糊自整定PID的液压马达驱动机床主轴速度控制研究

液压马达驱动机床主轴系统具有参数时变和高度非线性,传统PID控制器控制精度不高。针对液压马达驱动机床主轴系统速度控制问题,采用模糊自整定PID控制器实现液压马达驱动机床主轴系统的有效控制,并对控制效果进行仿真验证。构造了液压马达驱动机床主轴系统模型简图,建立了液压马达驱动机床主轴系统数学模型。对传统PID控制器参数,用模糊控制器进行实时整定,开发了模糊自整定PID控制器。最后,采用MATLAB对液压马达驱动机床主轴系统进行仿真。同时,与传统PID控制器的计算结果进行对比和分析。仿真结果显示:采用模糊自整定PID控制器的液压马达驱动机床主轴转速超调量小,具有更快的响应时间,跟踪精度高,同时系统能耗减少20%左右;即使受到较大随机干扰,模糊自整定PID控制器也能快速消除干扰,使机床主轴转速处于受控状态。采用模糊自整定PID控制器可以有效提高液压马达驱动机床主轴系统的动态稳定性以及抗干扰能力。

基于STM32的密炼机自整定PID温控系统设计

针对密炼机温度控制系统中人工整定PID带来的系统响应不及时、误差大等问题,该文设计了一种基于STM32的自整定PID温度控制系统。对于电动阀只能单极性调节问题,通过设置适当的工艺点来控制继电输出。为提高震荡曲线的辨识,采用参数归一化方法计算震荡曲线的临界增益。考虑密炼机的工作环境和系统响应曲线的频率特性,加入带有临界滞环控制的继电控制方法,提高了特征参数的精确性,更好地整定了PID参数。应用结果表明,基于STM32的PID整定温度控制系统能够将温度误差控制在1℃左右,且控制时间相比于人工PID控制系统提高了30%,极大地满足了密炼机的温度控制要求,具有良好的实用价值。

足式机器人腿部关节改进单神经网络PID控制算法研究

为了满足液压足式机器人在复杂环境中实现精确、快速的腿部关节控制需求,把单神经网络PID能够实时调节参数的优点运用到足式机器人液压机械腿关节的控制中,在单神经网络PID的基础上增加机械腿关节的位置和速度控制算法,形成改进单神经网络PID,实现了对神经元比例参数自调整、PID参数的自整定,能够较好地适应内、外参数的变化,增强了腿部关节的快速性、精确性。在Simulink中进行建模仿真以及在设计的以STM32为中央处理芯片的控制平台上进行实验测试,结果表明:改进单神经网络PID在足式液压机器人的腿部关节控制中具有响应速度快、超调量小、控制精度高、鲁棒性强等优点。

基于改进鲸鱼算法的收卷张力PID控制的性能优化

PID控制器的参数决定张力控制系统的稳定性和速度,因此研究收卷张力控制中经典PID控制器参数整定优化问题具有重要意义。以卷绕张力系统为切入点,结合PID和改进的鲸鱼优化算法,设计了基于改进鲸鱼算法(L-WOA)的PID张力控制器;为了提高PID整定参数方法的收敛精度和速度,在进行整定时结合了改进鲸鱼算法;建立数学模型和动态转矩平衡方程,分析了线速度和卷径对卷材张力的影响;分别使用改进鲸鱼算法和其他多种算法进行了参数优化。仿真结果表明,采用改进鲸鱼算法优化PID的控制策略具有响应速度快、控制输出稳定、抗干扰能力强、鲁棒性好等优点。

Linear Programming for Optimum PID Controller Tuning

This work presents a new methodology based on Linear Programming (LP) to tune Proportional-Integral-Derivative (PID) control parameters. From a specification of a desired output time domain of the plant, a linear optimization system is proposed to adjust the PID controller leading the output signal to stable operation condition with minimum oscillations. The constraint set used in the optimization process is defined by using numerical integration approach. The generated optimization problem is convex and easily solved using an interior point algorithm. Results obtained using familiar plants from literature have shown that the proposed linear programming problem is very effective for tuning PID controllers.

基于RBF神经网络整定PID的电液比例系统位置控制研究

针对凿岩机械臂的电液比例系统位置控制精度问题,提出了一种基于径向基函数(RBF)神经网络整定PID的电液比例系统位置控制方法。首先,在AMESim中搭建了阀控非对称液压缸的电液比例系统简化模型,设置了各个模块的参数;然后,利用MATLAB/Simulink搭建了系统闭环控制模型,通过不断更新RBF网络模型并修正PID参数,实现了基于RBF神经网络整定PID的电液比例系统位置控制目的;结合AMESim搭建的电液比例系统模型和Simulink下搭建的控制器进行了联合仿真;最后,基于凿岩台车机械臂实验平台,进行了电液比例系统位置控制实验。仿真结果表明:在受到外部干扰的情况下,RBF神经网络整定PID控制系统能够在0.3 s内控制活塞杆重新运行至目标位置,平均响应时间为1.5 s,位置精度误差不超过5 mm。实验结果表明:与常规PID控制方法相比,RBF神经网络整定PID控制活塞杆位置精度误差降低了75%,位置精度误差在工程实际要求的10 mm范围以内,因此,RBF神经网络整定PID算法可以有效提高电液比例系统的位置控制精度,满足凿岩机械臂实际工作中对电液比例系统位置精度的控制要求。

基于参数自整定模糊PID的BLDC控制研究

为解决传统PID控制在无刷直流电机调速系统中的控制精度低、效果不佳等问题,设计了一种基于参数自整定模糊PID控制的调速系统。通过在Matlab/Simulink仿真软件中建立了无刷直流调速系统的模型,分别采用传统PID控制、模糊PID控制和参数自整定模糊PID控制来对转速环进行调控,而电流环则采用PID控制。通过对比研究结果发现,采用参数自整定模糊PID控制的调速系统具有许多优势。系统的超调量较小,控制效果较好,同时提高了系统的鲁棒性。通过搭建模型并进行仿真实验,证明了采用参数自整定模糊PID控制的调速系统在解决无刷直流电机调速系统控制精度低、效果不佳等问题方面具有优势。这一方法能够有效提升系统的控制性能,并增强系统的鲁棒性。该无刷直流电机的调速系统可以稳定、可靠运行,满足使用需求。

基于改进WOA参数优化的反应釜PID控制器

为了解决工业中传统PID控制算法对于大时滞、非线性系统较难取得良好的控制效果的问题,提出一种基于改进鲸鱼优化算法(IWOA)的PID控制器整定算法。该算法考虑均衡算法的探查以及开发能力,引入非线性收敛因子;为了提高算法的勘察能力,避免陷入局部最优的情况,引入正余弦扰动因子改进位置更新策略;最后以化工反应中反应釜温度为被控对象,对其PID控制器进行参数自整定实验,并将结果与WOA算法、Z-N整定算法、PSO算法进行对比,验证了IWOA算法在优化PID控制器工程上的优越性。

基于继电反馈PID自整定的加热系统

某工厂对某种液体进行加热控制,针对某液体复杂的反应过程,设计出带自整定功能的PID自动调节加热设备。该设计以意法半导体公司(ST)的STM32F103C8T6为控制器,以PT100为温度采集元件,控制可控硅进行过零功率调节,通过MCGS触摸屏来显示,设定有关波形和参数,在控制过程中,可以根据有关加热要求选择多种整定参数,以满足液体的不同动态响应类型。该文主要介绍系统硬件组成原理框图,给出系统主要硬件电路图和自整定算法的工作流程,并对PID程序编制的一些关键点进行说明。实验证明加热系统能满足工厂要求。

AUTOMATIC TUNING OF PID CONTROLLERS IN THE THERMAL POWER UNIT LOAD CONTROL SYSTEM

A method of measuring the interactions in a multivariable control sys-tem(MVCS)in time domain is defined in this paper.An intelligent decoupling com-pensator is designed in terms of the concept of fuzzy control,so that the auto-tuningof controllers’ parameters in a 2×2 MVCS can be turned into that of two independentsingle-loop control systems(SLCS).The method presented in the paper has success-fully been used in a simulation experiment on the automatic tuning of a coordinatedcontrol system(CCS)in the drum-boiler turbogenerating unit(DBTU)and the simu-lation results axe satisfactory.

基于模糊自整定PID控制的真空炉温度系统的设计及仿真

作为一种在低于常规大气压环境下实施的冶金工艺,真空冶炼技术旨在通过降低氧化风险来优化金属及其合金的硬度特性。此技术在稀有金属提炼、特殊合金制备及高端钢材生产中具有越发广阔的应用前景。鉴于传统PID控制在真空冶炼炉温度调控中面临的显著滞后性挑战,为提升系统运行的鲁棒性与精确性,深入探讨了常规PID控制与模糊自整定PID控制的基本原理,并创新性地引入了模糊自整定PID控制策略。利用MATLAB平台中的Simulink模块与Fuzzy工具箱,针对真空冶炼炉的温度控制过程进行了详尽的仿真模拟,重点评估了温控系统的超调幅度与调节速度等关键性能指标。结果显示,与传统的PID控制方法相比,模糊自整定PID控制方案在稳态保持与动态响应方面均展现出显著优势,控制效果更优越。

基于模糊自整定PID的双容水箱串级液位控制系统研究

双容水箱串级液位控制具有抗干扰能力强、超调量小、过渡过程较短等特点。传统的PID算法和参数整定方法难以达到期望的控制效果。因此,针对双容水箱串级液位控制,利用模糊推理的方法实现在线自整定PID参数,设计相应的模糊PID控制器,基于Simulink仿真建模,对比传统的PID与模糊自整定PID输出响应曲线发现,该模糊自整定PID系统具有更好的鲁棒性,抑制系统超调以及对控制参数变化的自适应能力更强。

Neural Model-Based Self-Tuning PID Strategy Applied to PEMFC

This paper illustrates the benefits of a self-tuning PID strategy applied to a proton exchange membrane fuel cell system. Controller parameters are updated on-line, at each sampling time, based on an instantaneous linearization of an artificial neural network model of the process and a General Minimum Variance control law. The self-tuning PID scheme allows managing nonlinear behaviors of the system while avoiding heavy computations. The applicability, efficiency and robustness of the proposed control strategy are experimentally confirmed using varying control scenarios. In this aim, the original built-in controller is overridden and the self-tuning PID controller is implemented externally and executed on-line. Experimental results show good performance in setpoint tracking accuracy and robustness against plant/model mismatch. The proposed strategy appears to be a promising alternative to heavy computation nonlinear control strategies and not optimal linear control strategies.