A Hybrid Modeling for the Real-time Control and Optimization of Compressors

This paper proposes a hybrid compressor model for the purpose control and optimization of vapor compression systems. Unlike those existing models, this model is determined by only the inlet and outlet conditions of compressor without requiring detailed geometric specifications, and only the variables responsible to the system performance, which can be measured and controlled, are selected as the input/output (I/O) of the models. The model is derived based on the concept of volumetric efficiency and the assumption of a polytropic compression process. The unknown empirical parameters of the model are identified by the nonlinear least squares methods. The effectiveness of the proposed model is validated by the compressor catalogs data obtained from the manufactures. Results show that the model is accurate and robust and gives a better match to the real performances of compressors over the entire operating range than the existing models. This model is expected to have wide applications in real time control and optimization of vapor compression systems.