A Full Dynamic Model of a HVAC Vapor Compression Cycle Interacting with a Dynamic Environment

This paper presents an advanced switched model approach for vapor compression cycle (VCC) systems with shut-down and start-up operations. Building upon recent work [2], a full dynamic system model with switched moving-boundary components is presented that is able to accommodate severe transients in heat exchanger dynamics. These new switched heat exchanger models are created with uniform model structures, but with combinations of different model representations. It is shown that switching schemes between different representations handle the transitions of dynamic states while keeping track of vapor and liquid refrigerant regions during stop-start transients. The dynamic system model is created in Matiab/Simulink and is successfully verified on an experimental test stand. A combined VCC/environment is simulated with a hysteretic temperature controller in a case study. The qualitative accuracy of the case study results demonstrate the potential for this dynamic switched model approach for controller designs, including compressor cycling, in VCC systems.