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Variable speed fan powered terminal units

The October 2017 issue of the ASHRAE journal includes an article about fan-powered VAV terminal units. The article states that:

EnergyPlus, version 8.7, was recently released and it now states that it allows the user the simulate modulation of the terminal unit fan airflow through a part load fan curve or a performance table

I might be mistaken but I was under the impression that FP terminal units in EnergyPlus could only be modeled with constant volume fans, as specified in the documentation. I checked the EnergyPlus 8.7 release notes but couldn't see anything about FPB and part load fan performance. I thought that maybe they were referring to the new Fan:SystemModel object but I swapped the Fan:ConstantVolume for a Fan:SystemModel (with a typical VAV fan part load curve) in the 5ZoneVAV-ChilledWaterStorage-Mixed_DCV_MaxZd example file but the fan seemed to run similarly to a Fan:ConstantVolume. Am I missing something?