采用旁通阀定压差控制的冷水泵功耗特性试验研究

对采用旁通阀定压差控制的某办公楼变流量空调冷水泵功耗进行了研究。首先建立了一次泵的功耗模型,计算了旁通阀压差设定值对变速冷水泵瞬时功耗和全年功耗的影响,并与实验数据进行了对比。结果表明,旁通阀的定压差平衡状态存在一个上限流量,其值随压差设定值单调增加,同时其工作压力可划分3个特性区：欠压区、定压区和超压区;旁通阀的压差设定值对变速冷水泵的运行有显著影响,当旁通阀压差设定值取最远端用户的供回水压差时,变速冷水泵的功耗最小。

Experimental Analysis on Power Consumption of Chilled Water Pump by Constant Pressure Difference Method with Bypass Valve

The power consumption of frequency conversion chilled water pump of an office building regulated by constant pressure difference method with bypass valve is studied experimentally.A model of power consumption of chilled water pump is proposed.The effects of pressure difference set point of bypass valve on instantaneous and annual power consumption of chilled water pump are analyzed.The simulation results are validated experimentally,which shows that there is a maximum water flow rate which increases with the increase of the pressure difference set point of bypass valve at equilibrium state.There are three pressure operation regions of the bypass valve： under pressure region,constant pressure region and over pressure region.The power consumption of frequency conversion chilled water pump is affected by the pressure difference set point of bypass valve significantly,and it would be minimized as the pressure difference set point of bypass valve is equal to the pressure difference between supply water and return water of the farthest user.