Research On Method For Predicting Annual Power Saving Rate Of Air Conditioning Water System With Frequency Conversion Reconstruction

Existing office building frequency energy-saving reconstruction is an importanttechnical direction of the energy management contract (EMC) industry is of greatsignificance for the lower level of building energy consumption in China. Theprediction accuracy of annual energy-saving rate is related to the feasibility of thereconstruction project, the enthusiasm of the owners, the investment risk. But inactual projects, energy-saving rate forecast also exist many problems, such as theactual saving rate less than expectations, pump energy savings calculated in fullaccordance with the law of similarity, the coefficient of performance of the chiller cannot be determined. In response to these problems, the Shenzhen office building asan engineering example, the paper explore frequency energy saving technologicaltransformation of the annual energy-saving rate of the central air conditioning systemby heoretical analysis Contact measured data, and write the calculation procedure.First, based on the monitoring data according to the annual energy consumptionof15office buildings, analysis the Shenzhen office buildings loading rate correspondsto the time frequency. This is also the later saving rate data base. Meanwhile,according to the device parameters and the annual electricity consumption of15buildings, multiple regression analysis using SPSS software, and renovated officebuilding energy consumption regression model which is related the pump power andthe chiller power. The model can be used as initial judgment of the feasibility project.Second, study the variable flow impact on the energy consumption of the device,Analysis of the chilled water system fixed differential pressure control mode and thecooling water system given the difference in temperature control energy-savingprinciple, and pointed out that, due to the existence of the set pressure value givendifferential pressure control mode, the cooling water system due to the presence of thestatic head, both are not simple calculated in accordance with the law of similarity. Inaddition, through a large amount of data obtained by long-term measurements fromthe office building A, use the curve regression obtain relationship of the centrifugal chillers relatively COP with load rate change. And, ultimately, the water pump energysavings, chillers consume power related the loading rate are obtained.Finally, based on the foregoing analysis, research derived Shenzhen office buildingannual energy-saving rate prediction methods. in this process, using MATLABseeking multiple chillers load distribution rule which is conducive to energy saving.In order to apply to engineering calculation, this paper using Visual Basicprogramming obtained the water system of central air-conditioning energy savingtransformation of frequency conversion rate calculation software.