An Empirical Model for a Variable Speed Refrigeration System

Abstract:

This paper deals with an empirical dynamic model for decoupling control of the variable speed refrigeration system (VSRS). To cope with inherent complexity and nonlinearity in system dynamics, the model parameters are first obtained based on experimental data. In the study, the dynamic characteristics of indoor temperature and superheat are assumed to be first-order model with time delay. While the compressor frequency and opening angle of electronic expansion valve are varying, the indoor temperature and the superheat exhibit interfering characteristics each other in the VSRS. Thus, each decoupling model has been proposed to eliminate such interference. Finally, the experiment and simulation results indicate that the proposed model offers more tractable means for describing the actual VSRS comparing to other models currently available.

• Periodical: Advanced Materials Research (Volumes 383-390)
• Pages: 7563-7568
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.383-390.7563
• Online since: November 2011
• Authors: Hua Li, Ji You Fei
• Keywords: Capacity Control, Coefficient of Performance (COP), Decoupling Model, Superheat Control, Variable Speed Refrigeration System (VSRS)

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