A feedforward controller based on simplified physical models is descri
bed for air-handling units to supplement conventional PI control. Inve
rse static models of the controlled processes produce feedforward cont
rol action and the PI feedback loop compensates for modeling errors an
d unmeasured disturbances. The models are configurable from plant desi
gn information and they operate using the sensor signals typically ava
ilable to an air-handling unit controller. The incorporation of feedfo
rward control reduces the reliance on the feedback loop and makes the
tuning of the PI controller less critical. Low gain (default) control
parameters may then be used in the feedback loop, thereby eliminating
the need for on-site tuning. This paper describes the control scheme a
nd models, and presents results from tests carried out using a simulat
ed air-handling unit.