Optimal Operation Research In Ice Storage Air Conditioning System

Abstract:The usage of ice storage air-conditioning system with the effect of transforming a part of power load in peak period to valley period was one way to alleviate the contradiction between power supply and demand and Save operating costs.However,the advantage of system operating economy could not be reflected because of unsuitable control strategies.Therefore,it was the most important problem of making the global optimal operation of ice storage air conditioning system to get the maximized benefit for users in economy.An ice storage air conditioning system of Huai’an city was focused on and its measured data and sample equipment were used to build mathematic model.The optimum operating mode of parallel pumps for chilled water system was proposed under different flow and different control methods.The effect of outdoor air conditions on terminal refrigeration and dehumidification was also researched to propose corresponding variable chilled water control strategy under the mode of single host cooling.BP neural network was used to predict hourly building load.It was found that one or two hidden layers were suitable to predict building load.The method of taking the average of multi-group data was used to deal with the uncertainty of prediction results.Based on accurate load forecast,a mathematic model of operation cost minimization was build and solved.Corresponding solving results proved that high COP of crew could always maintain to make the running cost minimized.According to the heat dissipation model of cooling tower and energy consumption model of cooling water pump,total power difference between constant frequency operation and cooling water pump variable frequency operation was compared to propose a control strategy of cooling fan.Therefore,total energy saving amount under high load conditions was improved through parallel operation of more than one cooling tower.Finally,based on global optimization of operating parameters for typical diurnal ice storage air conditioning system,operating parameters with minimized system operating cost was calculated under the condition of typical diurnal surrounding environment and building load.After optimization,operating cost of ice storage air-conditioning system could even save by 14.9%.