Collaborative Research: Design and Model-based Control of Nonlinear Chemical Processes

摘要：沃伦·D. Seider机构：宾夕法尼亚大学提案编号：0101237为了实现更大的盈利能力，过程设计人员一直在涉及复杂非线性的区域进行设计，这些区域的过程控制器继续面临严峻的挑战。 稳态多重性、极限环、混沌和参数敏感性是非线性的表现。 除了非线性之外，还有许多过程设计具有不稳定和/或非最小相位稳态。 在许多情况下，在不稳定的稳定状态下，或者在不稳定的稳定状态附近的稳定稳定状态下，通常涉及非最小相位行为（逆响应），操作更有利可图。 可以显示这种行为的工艺设计的实例是化学反应器、发酵反应器、流化催化裂化器、反应器-分离器-再循环装置、共沸蒸馏塔和再沸器。 这种设计的过程是众所周知的，更具有挑战性的控制比稳定和最小相位稳态的过程。这个宾夕法尼亚大学-德雷克塞尔大学的联合研究项目的目的是解决更有效和更容易操作的不稳定和/或非最小相位稳态的过程。 它是对过程中设计和控制之间的相互作用的研究，以及开发使过程控制更容易的过程设计的策略。 现有的化学和生物化学过程的设计与不稳定和/或非最小相稳态将进行研究，以确定设计功能，引起这样的过程行为。 如果可能的话，将为这些过程开发替代的新过程设计，以便保持相同的盈利水平，但消除不稳定性和非最小阶段行为。 对于不能找到这种所需的替代设计的过程，将开发新的微分几何，基于模型的控制律，适用于一般的非线性过程，无论是最小相位或非最小相位。 最初，控制律将被开发为一般的，非线性的，连续时间的过程，没有死区时间或输入饱和的限制。 随后，后两个并发症将得到解决，和方法将扩展到多输入多输出（MINO）系统和测试化学，石化和生化过程。 一个原型符号操作软件，给定一个过程模型，自动生成微分几何控制律将被开发，以简化其工业实施和测试。

ABSTRACTPI: Warren D. Seider Institution: University of PennsylvaniaProposal Number: 0101237To achieve greater profitability, process designers have been creating design in regions involving complex nonlinearity where process controllers continue to face stiff challenges. Steady state multiplicity, limit cycles, chaos, and parametric sensitivity are manifestations of the nonlinearity. In addition to the nonlinearity, there are many process designs that have unstable and/or non-minimum-phase steady states. In many cases, operation is more profitable at an unstable steady state, or at a stable steady state in the close proximity of an unstable steady state, often involving non-minimum-phase behavior (inverse response). Examples of process designs that can show such behavior are chemical reactors, fermentation reactors, fluidized catalytic crackers, reactor-separator-recycle plants, azeotropic distillation towers, and reboilers. Processes with such designs are known to be more challenging to control than processes with stable and minimum-phase steady states.This University of Pennsylvania-Drexel University joint research project is aimed at addressing more efficient and easier operation of processes with unstable and/or non-minimum-phase steady states. It is a study of the interactions between design and control in the processes, and strategies to develop process designs that make control of the processes easier. The designs of existing chemical and biochemical processes with unstable and/or non-minimum phase steady states will be studied to identify the design features that give rise to such process behavior. Alternative new process designs, if possible, will then be developed for the processes such that the same level of profitability is maintained but the instability and non-minimum-phase behavior are eliminated. For processes for which such desired alternative designs cannot be found, new differential-geometric, model-based control laws will be developed that are applicable to general nonlinear processes, whether minimum-phase or non-minimum-phase. Initially, control laws will be developed for general, nonlinear, continuous-time processes without deadtimes or input-saturation constraints. Subsequently, the latter two complications will be addressed, and the methods will be extended to multi-input-multi-output (MINO) systems and tested for chemical, petrochemical, and biochemical processes. A prototype symbolic-manipulation software that, given a process model, automatically generates differential geometric control laws will be developed to simplify their industrial implementation and testing.