Optimization of control system for modified configuration of a refrigeration unit

Abstract

The paper presents an optimization of temperature control system for the refrigeration unit. Basic technological limits, which have influence on a control quality are also described. From a technological point of view the considered refrigeration unit operates in two modes. It allows the temperature stabilization inside the chamber despite the layer of frost growing up on the surface of evaporator. It is the main reason of changes dynamic parameters of the refrigeration unit. Authors analysed other technological factors, which may disturb a temperature inside of the cold chamber. The main idea was to find robust control algorithms for the temperature control, which makes a process stable in any working point. At the final part of paper the selected real time experiments were presented. It shows typical working modes of the refrigeration unit and proof robustness of developed and implemented control algorithm.