某商业建筑高效制冷机房运行数据分析

Analysis of Operating Energy Data of a High⁃efficient Commercial Building Chiller Plant

制冷机房作为系统工程,其系统运行参数的变化(如冷冻水供回水温差)会对机房内不同设备的能效产生不同的影响,机房整体能效最优是机房节能运行的重要目标。针对现有建筑运行数据存储较多但对其分析较少的现状,采用数据挖掘技术,对某商业建筑制冷机房实际运行能耗、能效进行统计计算,并将其与负荷率、供回水温度、供回水温差等变量的相关性展开分析,揭示机房能效与各变量间的内在联系。研究结果显示:制冷机房单位面积制冷能耗约为16~17 kW·h/(m^(2)·a),冷水机组能耗占80%以上,冷水机组的能效表现主导了机房的整体能效表现,机房系统能效比(COPs)高于设计值6.06 kW·h/kW·h,达到了预期目标。机房整体能效与室外气温及负荷率、冷冻(却)水供回水温差、冷却水进水出水温度呈负相关关系,机房整体能效与冷冻水供回水温度主要呈正相关关系。冷水机组运行COP与机组负荷率和冷却水回水温度呈现一定相关性,且基本符合机组定冷却水温和AHRI变冷却水温工况下的选型曲线。

As a system of a chiller plant,there are different effects of energy efficiency caused by the changes of the operating parameters(such as the temperature difference of the supply and return chilled water)of the different equipment of the chiller plant.Optimizing the overall energy efficiency of the chiller plant is an important goal for the energy⁃saving operation of the plant.Currently,there is enough storage of data of building operation while less of the data is analyzed.Due to this condition,the data mining technology is utilized to calculate the actual operating energy consumption and energy efficiency of the chiller plant of the commercial building.In addition,the correlation of the variables such as the chiller part load ratio,supply and return water temperature,and the temperature difference of the supply and return water temperature were analyzed to reveal the internal relationship between the energy efficiency of the chiller plant and the variables.The results show that the annual cooling energy consumption of the chiller plant per unit building area is 16~17 kW·h/(m^(2)·a),and the energy consumption proportion of the chillers among the chiller plant equipment is over 80%.Moreover,the overall energy efficiency of the chiller plant is dominated by the energy efficiency of the chillers.The system coefficient of performance(COPs)of the chiller plant is greater than the design value of 6.06 kW·h/kW·h,which means the expected design goal is achieved under the operating condition.The COPs of the chiller plant is negatively correlated with the outdoor air temperature and the chiller part load ratio,and is mainly negatively correlated with the supply and return temperature differences of the chilled and cooling water.Additionally,COPs is mainly positively correlated with the supply and return temperature of the chilled water.Furthermore,there is a certain correlation between the operating COP of the chiller and the part load ratio of the chiller as well as the return temperature of the cooling water.The correlation basically conforms to the chiller performance curve under the constant cooling water temperature and AHRI variable cooling water temperature conditions.