内模控制在液位控制系统中的应用研究

根据液位系统具有大惯性和非线性的动态特性,本文设计了一种高鲁棒性的多内模预估控制器,并将其引入三容液位控制系统中,以指导学生进行课程设计.通过与常规PID算法的实验结果进行比较,可见采用内模控制参数调整方便,超调量小,系统可以获得良好的动态和静态性能.     

基于α阶逆解耦的多变量内模控制系统研究

由于工业过程控制中存在大时滞现象,使得单变量内模控制难以获得有效的控制,而多变量内模控制成为一种较好的控制策略。文中简单介绍了多变量内模控制的原理,分别基于主回路为控制对象、V规范解耦的原则和α阶逆解耦进行内模控制器的设计,阐述了各个控制器的主要思想及其设计的具体方法。通过仿真比较模型匹配与模型失配下的内模控制输出仿真图。由仿真结果可以得出,基于V规范解耦的内模控制器具有较好的控制效果,但是解耦效果存在缺陷,针对非线性系统提出的基于α阶逆解耦的内模控制系统具有较好的解耦和控制效果。     

基于dSPACE设计平台的过程控制系统

本文介绍了基于dSPACE设计平台的过程控制系统,阐述了dSPACE系统的框架、软硬件组成,并以水箱液位系统为研究对象,采用内模控制器为主调节器的双闭环串级控制,同时利用dsPACE的实时监测软件对实验过程进行了在线监测.结果表明,在该实时控制平台上,满足对液位的控制要求.     

基于模型降阶的分数阶鲁棒控制器

针对复杂高阶被控对象控制器设计及参数整定困难问题,提出了一种基于模型降阶的分数阶鲁棒控制器设计方法。首先将复杂高阶模型近似为含时滞环节的降阶分数阶模型,根据原模型的奈奎斯特曲线特征,结合序列二次规划法,得到降阶近似模型的参数值。在此基础上完成分数阶控制器的结构设计,通过公式推导,给出了最大灵敏度鲁棒性指标与控制器整定参数的新的计算方法,最后结合复合时域性能指标整定控制器参数。仿真结果表明,所设计模型降阶参数求解无需全局寻优,收敛速度快,且降阶模型很好地逼近原系统,设计的鲁棒控制器使原系统具有良好的控制品质。     

A3000过程控制实验系统开发——多容液位系统PID控制

分析单容液位系统、双容液位系统以及三容液位系统对多个客器串联后系统特性的影响,并对数学模型的建立和测定进行理论分析,对控制的经验方法和一种多容液位系统PID参数整定的经验公式,通过大量的实验数据进行验证.提出的参数设置规律,对工业的多容器液位控制系统设计有一定的参考价值.     

光电伺服控制系统多回路内模控制器分析与设计

针对光电稳定平台中伺服控制系统的模型不确定性、内外部扰动和传感器误差等各项因素,提出基于多回路、双自由度内模控制的稳定环控制器设计方法,实现对各项误差因素的控制器分层设计.首先,对伺服控制系统的单回路控制结构和多回路内模控制结构进行描述,并深入分析了两者的误差扰动和模型扰动抑制性能;然后,详细讨论了多回路内模控制结构中...     

基于H like模型的压电陶瓷作动器内模控制

针对压电陶瓷作动器的率相关特性降低应用端控制精度的问题,该文研究了基于Hammerstein like模型的内模控制策略。其中非线性部分由最小二乘支持向量机模型表示,动态线性部分由自回归历遍模型表示。在此基础上构建了系统逆模型,设计了内模控制器以实现对压电陶瓷作动器的跟踪控制,最后通过实验平台进行了验证。实验结果表明,实时跟踪100 Hz内的期望信号相对误差均小于10%,证明了所设计内模控制方案的有效性。     

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.     

舰载机纵向自动着舰导引系统H∞降阶控制器设计

利用H∞控制理论设计飞机纵向着舰导引系统时，主要问题是控制器阶数过高，机载计算机难以承受。采用基于稳定准则的加性降阶法，设计了某型飞机纵向着舰导引系统H∞降阶控制器。仿真结果表明，所设计的降阶控制器可完全满足着舰系统对抗扰和精确跟踪的要求。     

基于扰动转矩估计的导引头自适应内模控制

为了降低扰动转矩变化对导引头伺服控制系统的影响,提出了一种基于扰动转矩估计的自适应内模控制方案。首先建立导引头伺服控制系统的数学模型,设计系统的内模控制器;接着采用扰动转矩估计的方法,辨识导引头伺服控制系统转动惯量的变化情况;最后根据转动惯量的变化、通过线性自适应率自动调整内模控制器的参数,从而确保控制器的控制性能。实验结果表明,该控制方案对系统工况变化有着很强的自适应性,提高了导引头伺服控制系统的抗干扰性能和鲁棒性,取得了较好的控制效果。     

基于内模的萃取釜溶剂流量控制系统研究

针对超临界萃取技术中的萃取釜溶剂流量补偿问题,常规的PID控制无法达到理想控制,将内模控制(IMC控制)应用到萃取釜CO₂流量补偿的控制过程中,可克服扰动不可测的现象,从而提高了CO₂流量补偿系统的稳定性。此外,使用Matlab/Simulink对IMC控制进行建模与仿真,其结果表明,内模控制可较好地控制流量补偿精度,作为该系统的控制器是可行的。     

时滞系统的二自由度Smith预估控制研究

针对典型的工业过程控制对象,文中结合内模控制原理,为时滞控制系统设计了一种仅有两个滤波参数的二自由度Smith预估控制器,通过两个可调参数的调整能使系统同时具有良好的目标值跟随特性和干扰抑制特性,并结合Matlab仿真实验证明了其的有效性。     

一阶线性时滞系统的内模控制设计

内模控制是近年来发展起来的一种新型控制方法,分析它的原理对于工程应用和理论研究具有重要的意义。从IMC结构分析入手揭示了内模控制的本质,证明了该系统可实现对阶跃信号的无差跟踪及在阶跃信号扰动下可实现无差控制;介绍了时滞线性系统内模控制器和内模滤波器的设计方法。并基于MATLAB仿真研究表明,线性时滞过程的内模控制具有较好的鲁棒性,有一定的应用价值。     

基于Taylor展开法整定MIC-PID控制器参数

针对一类不稳定时滞过程,采用双环控制结构,首先使广义对象(内环)稳定,然后用Taylor级数展开法,根据内模控制原理设计外环控制器,得到等效的PID控制器参数的整定方法。仿真结果表明,整定后的系统不但具有良好鲁棒性,而且调节快速,适合于工程实际应用。     

Inverse model-based real-time control for temperature uniformity ofRTCVD

A reduced-order model describing a rapid thermal chemical vapor deposition (RTCVD) process is utilized for real-time model based control for temperature uniformity across the wafer. Feedback is based on temperature measurements at selected points on the wafer surface. The feedback controller is designed using the internal model control (IMC) structure, especially modified to handle systems described by ordinary differential and algebraic equations. The IMC controller is obtained using optimal control theory on singular arcs extended for multi-input systems. Its performance is also compared with one based on the Hirschorn inverse of the model. The proposed scheme is tested with extensive simulations where the full-order model is used to emulate the process. Several cases of significant uncertainty, including model parameter errors, process disturbances, actuator errors, and measurement noise are used to test the robustness of the controller to real life situations. Both controllers succeed in achieving temperature uniformity well within the desirable bounds, even in cases where several sources of uncertainty are simultaneously present with measurement noise     

Internal model control (IMC) approach for designing disk driveservo-controller

This paper presents a design procedure for disk drive servomechanism using an internal model control (IMC) structure. A typical disk drive actuator can be modeled as second order dynamics for low frequencies. However the response at higher frequencies shows resonant behavior which is difficult to model. We discuss the use of IMC structure for designing servo-controllers for disk drives. In this method, a second order nominal model of the plant is used to design an H ₂-optimal controller to attain minimum integral-error-square (ISE) performance. Then to maintain robust stability at higher frequencies, sufficient roll-off at such frequencies is provided by an H _∞ optimization procedure. Here, the H₂-optimal control is augmented by a low pass filter with sufficient high-frequency roll-off to ensure robust stability and robust performance. A multiplicative uncertainty bound is defined using the data of the disk drive servo plant's frequency response and the response of the nominal model, and this is then used to decide robust stability and robust performance bounds. Tuning of only one parameter of the IMC filter makes this design method easy and convenient. Simulation results for the designed controller are presented     

Partial internal model control

Internal model control (IMC) is a well-known and effective control scheme. However, when unstable processes are concerned, the original IMC structure cannot be directly used for control system implementation. In this paper, a new scheme called partial internal model control (PIMC) is proposed, which is capable of controlling both stable and unstable processes. In PIMC, a process model is expressed as the sum of the stable and antistable parts and only the stable part of the process model is used as the internal model. The process stable part is canceled by the internal model and the remaining antistable part is stabilized and controlled with a primary controller, which is usually a PID-type regulator when the antistable part is of a low order. Various properties of a PIMC system such as internal stability and robust stability are analyzed. The design of PIMC is discussed in detail. Various simulation examples are included for illustration and a real-time implementation on a motor system is presented     

基于Matlab的模糊PID控制系统设计及仿真

模糊PID控制是利用PID参数整定经验来使模糊控制器自动整定其参数,从而使PID控制器以变应变。文中采用Matlab软件设计模糊PID控制器,并应用于控制锅炉液位。通过实验仿真比较研究PID控制、模糊控制及模糊PID控制的控制效果。实验结果显示,模糊PID控制效果理想,具有较好的应用前景。     

Real-time electro-hydraulic hybrid system for structural testing subjected to vibration and force loading

Real-time electro-hydraulic hybrid system (REHS) with shaking table and force loading simulator is an essential experimental facility for evaluating structural performance subjected to simultaneously vibration excitation and force loading. The key feature of this paper is combination of a feedforward force controller including modified force inverse model compensator (MFIMC) and velocity feedforward compensator (VFFC) with an internal model control (IMC) to compensate the surplus force disturbance caused by active motion of shaking table and to obtain high fidelity force loading tracking performance. An acceleration tracking controller is also designed with modified acceleration inverse model compensator (MAIMC) to extend the acceleration tracking frequency bandwidth and to improve the acceleration tracking performance. The acceleration/force closed-loop transfer function model and their inverse model are identified and designed by multi-step recursive extended least squares (RELS) algorithm and zero magnitude error tracking controller (ZMETC) technology respectively because the identified transfer function model of the acceleration and force loading closed-loop systems may be a nonminimum-phase (NMP) system and their inverse model are instable. An acceleration and force modeling error compensator (MEC) are utilized in MFIMC and MAIMC to minimize the effect of the inaccuracy of identified model and designed inverse model. Experimental results obtained on a real uniaxial REHS with xPC rapid prototyping technology clearly demonstrate the benefit of the proposed compensation method.