Reinforcement Learning-Based Adaptive Control for Complex Nonlinear Systems: Application to a CSTR
DOI:
https://doi.org/10.17979/ja-cea.2026.47.13801Keywords:
Process control, Model reference adaptive control, Machine Learning, Gain schedulingAbstract
This work proposes an adaptive control strategy for concentration regulation in a Continuous Stirred Tank Reactor (CSTR), in which a reinforcement learning agent adjusts the gains of a PID controller online in order to impose a desired closed-loop dynamic behavior. The proposed methodology combines the interpretability and robustness of classical PID-type controllers with the adaptive capabilities of reinforcement learning through a reward function defined from the error between the system response and a reference dynamic behavior. To this end, an agent based on the Deep Deterministic Policy Gradient (DDPG) algorithm is employed. Simulation results show that the proposed strategy is able to maintain a more consistent dynamic response under variations in the operating point, outperforming classical adaptive control approaches such as gain scheduling.
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Copyright (c) 2026 Antonio Martínez-Roa, Juan D. Gil, Igor M.L. Pataro, Antonio del Rio Chanona, José L. Guzmán, Manuel Berenguel

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