中央空调冷冻水泵变频调速运行特性研究(1)

Research on Characteristics of Variable Frequency Chilled Water Pumps in Central Air-Conditioning Systems-Part 1

通过分析变频冷冻水泵及冷冻水管路在变负荷时的特性 ,得出了冷冻水泵的扬程与流量、总能耗与流量的一般关系式 ,同时针对特定的空调系统 ,提出了冷冻水泵“等效静扬程”的概念 ,并应用其对空调变负荷时冷冻水泵变频调速工况进行了研究。指出在中央空调系统中 ,由于冷冻水管路特性曲线随空调负荷而变化 ,在确定水泵变频调速运行工况点时已不能直接应用泵的相似定律 ,泵的能耗不与转速的三次方成正比 。

Based on analyzing the characteristics of variable frequency chilled water pump and chilled water loop resistance curves varying with air-conditioning loads,a general relationship,which determines the range of variable frequency of the pumps,between the capacity and the head of pump is obtained Meanwhile,in a air conditioning system with S eS 2 both equivalent static head and equivalent chilled water loop resistance curve are put forward and applied to study the characteristics of variable frequency chilled water pumps It is pointed out that the pump affinity laws can′t be directly used to determine the operating points of variable frequency pumps and the energy consumed by variable frequency chilled water pumps is not proportional to the cube of speed but varies with the capacities and the positions of operating air-handling units (AHUs)