Trial-and-error method for variable outdoor air volume setpoint of VAV system based on outdoor air damper static pressure difference control

Abstract

A variable outdoor air (OA) volume setpoint control method is proposed to solve the problem of mismatch between OA supply and demand in multi-zone VAV system. The method firstly obtains the OA volume setpoint according to the indoor CO2 concentration change and then combines the OA damper static pressure difference control method to discretize the continuous OA volume setpoint to obtain different grades of OA volume setpoint, and finally optimize the OA volume setpoint according to total volume demand of terminals. The experiment was done to verify the feasibility of this new method and the result shows that the proposed method can be well fitted with other control loops in the air-conditioning system to ensure the demand of indoor OA volume, and this method is also suitable for online applications.