本文采用控制阀作为测量装置，研制了一种虚拟空气处理机组（AHU）水位流量计。使用两个可测量输入（压差测量值和阀门开启位置）和三个常数（固有阀门特性、阀门系数和阀门权限）间接计算通过阀门的流量。因此，本文介绍的非侵入式虚拟流量计为计量障碍和挑战之一提供了一个解决方案:在AHU水平上的低成本、可靠的能源计量系统。由于虚拟流量测量是通过基于多个输入的间接计算实现的，因此与直接流量测量相比，测量误差的可能性显著增加。 本文首先介绍了虚拟流量计的数学模型。随后进行了灵敏度和误差传播分析，以研究流量精度。因此，阀杆位置是决定虚拟流量计精度的主要变量，因此，除阀杆位置外，其他输入的误差影响较小。当阀杆位置误差在0.5%到2.0%之间时，虚拟流量计的精度在阀门权限为1时为1.96%到7.83%，在阀门权限为0.3时为0.92%到3.60%。该模拟研究已经证明，在AHU水平上使用控制阀作为测量装置是可行的，以提供令人满意的结果。 在下一阶段的研究中将进行更多的实验测试。引文:伊利诺伊州芝加哥ASHRAE Transactions第118卷第1部分

In this paper, a virtual Air handling unit (AHU) level water flow meter is developed by using a control valve as a measurement device. The flow through the valve is indirectly calculated using two measurable inputs (differential pressure measurements and valve opening positions) and three constants (inherent valve characteristics, valve coefficient and the valve authority). Thus, the non-intrusive virtual flow meter introduced in this paper provides a solution to one of the measurement barriers and challenges: a low cost, reliable energy metering system at the AHU level. Due to the fact that the virtual flow measurement is achieved by an indirect calculation based on multiple inputs, possibility of measurement errors is significantly increased comparing with a direct flow measurement. In this paper, we first introduce mathematical models of the virtual flow meter. Sensitivity and error propagation analyses are carried out afterwards to investigate the flow accuracy. As results, the valve stem position is a dominant variable in determining the accuracy of the virtual flow meter and thus the error impacts from other inputs except the valve stem position are minor. When the valve stem position error ranges from 0.5% to 2.0%, the accuracy of the virtual flow meter ranges from 1.96% to 7.83% under the valve authority of 1 and the accuracy ranges from 0.92% to 3.60% under the valve authority of 0.3. This simulation study has proven that it is feasible to use the control valve as the measurement device at the AHU level to provide satisfactory results. More studies will be carried out on experimental tests in next phase study.