Modelagem de um sistema de refrigeração de bebidas com identificação dinâmica de parâmetros e predição do tempo de estabilização da temperatura para economia de energia

Abstract

This work deals with the reduction of electric energy consumption in beverage coolers through its shutdown outside of the operating shift. Experiments were conducted considering a commercial model of beverage cooler under to two levels of thermal load variation, loaded with 32 and 64 liters and with the thermostat adjusted for two distinct levels temperature, moderate cold and maximum cold. The results demonstrated a maximum error of 2.7% in predicting the time to turn on the compressor. Considering the test conditions, the proposed method achieved an electrical energy saving of 5.6%, with the refrigerator operating at maximum beverages load (64 liters) and in the maximum cold configuration. However, the method provided 26% electricity savings with a maximum load of 64 liters and with the thermostat set to moderate cold. The results were satisfactory, showing the feasibility of the proposed model, using the Newton's Cooling Law, as a method to the plant identification and to predict the time to turn on the compressor. This provided for the effective reduction in energy consumption of beverage cooler without loss of temperature performance at the time of product consumption.