变频技术在空调冷冻水变流量系统中的应用及节能分析

摘要

采用变频调速装置对中央空调冷冻水系统冷源侧进行变流最控制,控制系统采用恒定供回水温差的控制模式,应用增量式PID控制方法改变变频器输出,调节水泵转速,降低了较低用户负荷时水泵的电能耗,与传统的定流量运行比较节能效果明显；控制系统采用LonWorks总线技术,组网灵活,控制精度高,系统稳定性好.%This paper presents a method which uses frequency conversion technology in central air-condition chilled water system of variable flow. In this system, the output of frequency converter can be altered by augmenter PID control rule which is used in control of invariable difference in temperature between water supply and backwater, and the rotating speed of water pump can be changed correspondingly, so when the user load is small ,the electric energy consume can be reduced. The effect of energy-saving is visible comparing with the conventional Air-Condition chilled water constant flow system. LonWorks technology is used in the control system, it can be constructed flexibly and has high precision and stability.