Abstract: One embodiment of the present application is a gas turbine engine with a compressor that includes a variable geometry mechanism to vary working fluid flow area. A desired state of this mechanism is selected different than a current state to change the amount of flow area. The mechanism has a hysteresis band corresponding to a difference between increasing the flow area to reach the desired state and decreasing the flow area to reach the desired state. To control operation of the mechanism within this hysteresis band, a determination is made whether the desired state corresponds to a greater flow area or a lesser flow area relative to the current state.