A new approach to autotuning PID controllers
DOI:
https://doi.org/10.17979/ja-cea.2025.46.12077Keywords:
Adaptive control, Autotuner, Identification for control, Input and excitation design, Closed loop identificationAbstract
This work presents a new approach to the autotuning strategy for controlling pH in raceway reactors, based on classical relay-based autotuning principles. A relay applied to reference method is proposed that allows seamless integration into existing control loops without the need for manual recalibration across seasons or operator intervention. Two different models were identified: first-order with time delay and integrator with time delay, and a classification algorithm was introduced to evaluate disturbances in solar radiation, improving the reliability of autotuning in the presence of clouds. The control scheme consists of a Proportional-Integral (PI) controller with antiwindup and static feedforward compensator to counteract the radiation effect, with all its parameters automatically adjusted. It has been shown by simulation that the adaptive algorithm allows an improvement in pH regulation compared to a fixed-parameter scheme. Furthermore, the implementation in the real system proves that it can be easily transferred to a real reactor without the need for changes in the algorithm parameters.
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Copyright (c) 2025 Malena Caparroz, Kristian Soltesz, Tore Hägglund, José Luis Guzmán, Manuel Berenguel
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