Hybrid NMPC of supermarket display cases

SARABIA DANIEL; CAPRARO FLAVIO; LARSEN LARS; DE PRADA CESAR

CONTROL ENGINEERING PRACTICE

Pergamon

Año: 2009 vol. 17 p. 428 - 441

0967-0661

This paper presents a NMPC of a supermarket refrigeration system. This is a hybrid process involving switched nonlinear dynamics and discrete events, on/off manipulated variables (valves and compressors), continuous controlled variables (goods temperatures) and finally, several operation constraints. The hybrid controller is based on a parameterization of the on/off control signals in terms of time of occurrence of events instead of using directly binary values, in this way, we can re-formulate the optimization problem as a NLP problem. A rigorous model of a real supermarket refrigeration system is presented, as well as results of the hybrid controller operating on it.