Direct feedback linearization based control of CO2 demand controlled ventilation

The control of outdoor air intake rates in mechanically ventilated buildings based on indoor carbon dioxide (CO₂) levels has the potential for reducing the energy consumption associated with building ventilation in some commercial and institutional buildings. A state space model system of demand controlled ventilation (DCV) is developed. It is found that the dynamic model is formulated as a bilinear system. Direct feedback linear (DFL) is applied for linearization of the nonlinear model of DCV system, and a linear input-output model is obtained. DFL control system is designed and simulated based on SIMLINK. Simulation results for a typical o zone show that DFL control system can achieve good performance in celerity, stability and other aspects. Also the potential of keeping comfort and maintaining energy optimal performance is demonstrated by this methodology.