The use of variable-frequency drives (VFDs) in centrifugal pumps is becoming increasingly common to improve energy efficiency and optimize process control. However, quantifying the actual effect of frequency variation on flow rate, head, and absorbed power is not always straightforward.
I therefore created a simple spreadsheet that plots the characteristic curve of a centrifugal pump based on a set of assigned flow–head data points, and also shows how the curve changes as the VFD frequency varies.
You can download the spreadsheet by clicking this link.