变水流量空调系统流量控制的研究

摘要

Presently it is quite common to apply variable water flow rate control in air conditioning system. In order to measure the water flow rate, the conventional method is to install flow meter or flow sensor in the system. However, this method will cause the increase of early stage investment cost for the air conditioning system. In present study, a low cost and practical flow measurement control method was introduced, which calculates water flow by the mathematic model obtained through regression analysis method based on the relationships among water flow, water pump frequency and water head. The experimental verification results show that, the average error of this method is small, and the new method has a good universality; therefore, the new method is very suitable to control the frequency of water pump and the open degree of water bypass valve, and to realize variable water flow rate control.%当前的中央空调系统中，应用变水流量控制已经相当普遍。为获得系统水流量参数，通常的方法是安装流量计或流量传感器。但是这种方法会使空调系统的初期投资增加。本文将介绍一种成本低且实际可行的流量测量控制方案，依据水泵流量和频率以及扬程的关系，通过回归分析得到的数学模型来计算水流量。经试验验证，该方案的平均误差小，通用性强，可用于控制空调系统水泵频率和水路旁通阀开度，实现变水流量控制。