Publicado

2017-01-01

Optimal control of MIMO dead-time linear systems with dead-time compensation structure

Control óptimo con estructura de compensación de tiempo muerto para sistemas multivariábles con retardo

Palabras clave:

Optimal control, Dead-time systems, neonatal incubator (en)
Control óptimo, sistemas con retraso, incubadora neonatal (es)

Autores/as

State space optimal controllers became popular over the last decades mainly because of its performance and robustness properties, as well as easy extension for multi-variable systems (MIMO). On the other hand, many industrial processes present dominant dead-time which may cause issues related to performance or even stability. Despite of its importance, few works from optimal control may be traced for this matter. In order to deal with dead-time effect one may use dead-time compensation (DTC) structures, mainly applied for single-variable systems (SISO). Within this context, this work proposes to modify a prediction structure recently proposed aiming to combine the best properties of both DTC and optimal control for MIMO linear systems. Simulation results along with the application to an experimental setup of a neonatal incubator prototype are presented to highlight the advantages and show the effectiveness of the proposed control strategy, as well as its practical aspect.
Los controladores óptimos en espacio de estado han tenido bastante popularidad en las últimas décadas, principalmente, debido a sus buenas propiedades de robustez, desempeño y la posibilidad de aplicación en sistemas multivariables. Sin embargo, muchos procesos industriales presentan retrasos dominantes entre sus variables los cuales pueden ocasionar problemas de desempeño y estabilidad. A pesar de su importancia, existen pocos trabajos reportados de control óptimo que tratan este problema. Para mitigar el efecto del retraso pueden ser usadas estructuras compensación de retraso conocidas como DTC y usadas principalmente en procesos monovariables. En este trabajo se propone la modificación de una estructura de predicción recientemente propuesta con el objetivo de combinar las mejores propiedades de un DTC y del control óptimo para controlar procesos lineares multivariables (MIMO). Resultados de simulación y la aplicación al prototipo de laboratorio de una incubadora neonatal son usados para mostrar las ventajas, efectividad y practicidad de la estrategia propuesta.

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Citas

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