In view of the fact that conventional optimization methods fail to take into full consideration the influence of the evaporator superheat on the efficiency and stability of compression type water chiller
leading to a high superheat set point and non-optimum energy efficiency
an energy saving optimization method which can minimize the degree of superheat is proposed to further exploit the energy saving potential of water chillers. By analyzing the mechanism of water chiller refrigeration cycle
the steady-state model and energy consumption model of the system are established. Besides
the experimental method for obtaining the minimum stable heat curve is also put forward. In this paper
a steady-state model of cold water chiller is established
in which the minimization of the total energy conservation is taken as the optimization goal
and genetic algorithm is used to calculate the optimal set points. Based on the minimum stable superheat curve
the superheat constraint is adjusted online under different heat loads. The comparison of experiment results shows that the proposed method can effectively expand the optimization range
obtaining lower superheat value and an average energy saving of 1.92% than existing optimization methods under typical working conditions in summer.
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references
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