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[EnergyPlus_Support] Real world HVAC question - DCV using CO2 sensors with VAV dampers

This question has nothing to do with simulation as such. What is the best way to use / control a Demand Control Ventilation (DCV) System which uses a combination of CO2 sensors and motorized Variable Airflow Volume (VAV) dampers.

I will suggest a control stradegy to illustrate the question:

CO2 sensors report the zone CO2 level at given timestep.
Allowable upperbound CO2 level is 800ppm.
Outdoor Air (ODA) CO2 level is 400ppm.
Minimum damper position allows at least 0.3 of fully open flow.
Maximum damper position is fully open, i.e. 1.0 of full flow.

Stradegy 1::
Control is such that at 400 ppm, Damper will be at 0.3 of full flow.
At 800 ppm or more, Damper will be fully open.
Damper is linierly actuated between 0.3 to 1 as the level of zone CO2 increases from 400 ppm to 800 ppm.

Stradegy 2::
Damper remains at 0.3 untill CO2 level reaches 750 ppm, then linierly opens from 0.3 to 1.0 as the level increases to 800 ppm.

Stradegy 3::
Erratic opening and closing of damper only when level reaches or goes over 800 ppm.

Stradegy 4::
Exponencial, or other curve to control damper other than liniear.

Origional question...how are these systems controlled in practice?
Anyone with experience, here?



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