冷却水系统变流量的全年工况节能分析

Analysis on Energy-saving of Year-round Operation Conditions with Variable Flow Cooling Water System

本文对变流量时冷却水系统的节能效果进行了分析。首先以冷却变频水泵调速引起冷水机组和水泵系统的全年节能量的变化为优化目标函数,分析了变流量时不同控制方式对水泵和机组能耗的影响。而后建立了冷却水变流量时系统的节能优化模型,并应用实例进行分析,计算得出了不同控制方式下冷却水系统全年以及不同负荷率工况下的运行能耗,在此基础上得到了最优化的控制方法。研究结果表明:冷却水系统采用变流量是可行的,系统综合节能效果显著;定温差+最小压差控制是相对节能的变流量控制方式,同定流量控制比较,系统全年节能率为6.07%。

In this paper,energy-saving effects of cooling water system under variable flow conditions were analyzed.Firstly,with the inverter technology,the energy-saving of chiller and cooling water pump during year-round was taken as the optimal target,the influences of different variable speed control strategies on energy consumption of chiller and cooling water pump were analyzed.Secondly,the energy efficiency optimization model for variable flow cooling water system was established.Based on the case study,the operation energy consumption was calculated under different control strategies and different cooling load conditions,and therefore the optimal control strategy was obtained.The results indicated that it was feasible to adopt the variable flow strategy,the corresponding energy-saving effect was significant.In addition,the control strategy of constant temperature difference with the minimum pressure difference was more energy efficient compared to the constant flow control strategy,the year-round energy-saving rate was 6.07%.