Optimal control of distillation columns based on a multiple model switching strategy
WANG Zhenlei1, CHEN Dengqian1, WANG Xin2
1. Key Laboratory of Advanced Control and Optimization for Chemical Processes, East China University of Science and Technology, Shanghai 200237, China;
2. Center of Electrical & Electronic Technology, Shanghai Jiao Tong University, Shanghai 200240, China
Abstract：Distillation columns have many features such as their nonlinear control equations and many random disturbances, which contribute to parameter variations in the mathematical model. This paper describes a method that combines multi-model switching control with the linear quadratic regulator (LQR) optimal method to solve the control problems that result from the parameter variation. The method combines the advantages of both methods. The parameter interval is first decomposed into sub-intervals with sub-models then built and combined into a model set. A sub-optimal controller is then designed using the LQR method and the controllers are switched to get the optimal controller based on the performance index function. Comparison of this method with the single LQR optimization method shows that with this method, the output concentrations at the top and the bottom of the distillation column remain stable when parameter Par jumps from 20 to 19.5.
王振雷, 陈登乾, 王昕. 基于多模型切换策略的精馏塔最优控制[J]. 清华大学学报（自然科学版）, 2016, 56(4): 430-436.
WANG Zhenlei, CHEN Dengqian, WANG Xin. Optimal control of distillation columns based on a multiple model switching strategy. Journal of Tsinghua University(Science and Technology), 2016, 56(4): 430-436.
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2016, Vol. 56 
