Diseño de un controlador PID adaptativo para el control de concentración en un reactor químico de tanque agitado continuo, bajo un entorno de simulación Hardware in the Loop.

Abstract

The objective of this work was the design and implementation of an adaptive integral proportional controller (PID) by reference model for the control of the concentration of a continuous stirred tank chemical reactor through simulations in the Matlab® software and implementation through the Hardware in the Loop environment. It started with the establishment of the mathematical model of the plant, then it was linearized in a specific point by Taylor series to find the transfer function that best represents the system, later a classic PID controller was designed through Ziegler Nichols´ tuning method with a step type entrance. The adaptive PID controller by reference model was raised with the MIT law, where a second-order reference model was chosen that meets the characteristics required by the designer and an adaptation law that reduces the error between the reference model and the set point. The mathematical models of the plant, classic and adaptive controllers were simulated in the Simulink toolbox, where they were evaluated against different input signals, adding noise to the control loop. The implementation in the Hardware environment in the Loop consisted in programming the Arduino card Due directly from the PC with the Simulink toolbox, both for the model of the plant, as well as for the two controllers. These are connected through the analog inputs and outputs that have the Arduino card. To validate the operation of the controllers, the error was quantified through the Absolute Integral Error (AIE) technique, where it was shown that the adaptive PID controller by reference model generated a smaller amount of error optimizing the operating variables of the chemical reactor of the stirred tank. It is advisable to analyze the controllers designed to interact with real plants in the industry.