Application of a control strategy based on PWA model in CSTR system

doi:10.11949/j.issn.0438-1157.20151844

Abstract

Abstract:

There will be some abnormal working states in the process of chemical production, so the controller of the system often needs to be reconfigured in order to keep the system running normally. In view of this situation, a control strategy based on piecewise affine (PWA) model is proposed. In the strategy, a system is modeled in PWA form and an explicit model predictive control algorithm is applied to control the system. When abnormal operating points are detected, formal verification is first used to decide whether the controller needs to be reconfigured or not. By this way, it not only saves production time, but also improves the control efficiency. An application case study on CSTR system is given to illustrate the effectiveness of this strategy.

Key words: PWA model, explicit model predictive control, formal verification, CSTR, dynamic simulation

摘要：

在化工系统实际运行过程中,常常会出现一些不正常的工作状态,为了使系统运行状态能够避开这些不正常的工作状态,往往需要对控制器进行重构。针对这种情况,本文阐述了一种基于分段仿射模型的控制策略,该控制策略采用显式模型预测控制算法对系统进行控制,当检测到系统出现异常工作点时,先对系统进行形式验证,根据验证结果,再决定是否进行控制器重构,这样,既大大节约了生产时间和成本,也提高了控制效率。将该控制策略应用到连续搅拌反应釜系统中,取得了显著的应用成效。

关键词: 分段仿射模型, 显式模型预测控制, 形式验证, 连续搅拌反应釜, 动态仿真

CLC Number:

TP273

WANG Yuhong, YANG Pu. Application of a control strategy based on PWA model in CSTR system[J]. CIESC Journal, 2016, 67(3): 865-870.

王宇红, 杨璞. 一种基于PWA模型的控制策略在连续搅拌反应釜中的应用[J]. 化工学报, 2016, 67(3): 865-870.

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