Reinforcement Learning-Based Adaptive Control for Complex Nonlinear Systems: Application to a CSTR

Authors

  • Antonio Martínez-Roa Universidad de Almería
  • Juan D. Gil Universidad de Almería
  • Igor M.L. Pataro Universidad de Almería
  • Antonio del Rio Chanona Imperial College London
  • José L. Guzmán Universidad de Almería
  • Manuel Berenguel Universidad de Almería

DOI:

https://doi.org/10.17979/ja-cea.2026.47.13801

Keywords:

Process control, Model reference adaptive control, Machine Learning, Gain scheduling

Abstract

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.

References

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Published

2026-09-01

Issue

Section

Ingeniería de Control