Hybrid neural network controller design for a batch reactor to produce methyl methacrylate

Abstract

Methyl methacrylate (MMA) production in an exothermic batch reactor provides a challenging problem for studying its dynamics behavior and temperature control. This work presents a neural network forward model (NN) to predict a concentration of methyl methacrylate, a jacket temperature and temperature profile in the reactor. An optimal NN model has been employed to predict state variables incorporating into a model predictive control (MPC) algorithm to determine optimal control actions. To control the temperature, neural network based control approaches: a neural network direct inverse control (NNDIC) and a neural network based model predictive control (NNMPC) have been formulated. In addition, a dynamic optimization approach has been applied to find out an optimal operating temperature to achieve maximizing the MMA product at specified final time. The robustness of the proposed control strategy is investigated with respect to changes in operating parameters: rate of reaction, heat of reaction and overall heat transfer coefficient. Simulation results have indicated that the NNMPC is robust and gives the best control results among the PID and NNDIC in all cases.