A dynamic control model to improve the response speed for an air-condition system

Abstract

A procedure for deriving a dynamic model of an HVAC system was described in this paper. The system consists of a zone, cooling coils and fan. Room thermal balance model and dynamic model of HVAC control system components including sensor, cooling coils and ducts, were established. These models accurately predicted the effect of inlet air temperature, airflow rate, and inlet chilled water temperature on the room temperature. During closed loop control of output air temperature, chilled water flow rate was used as a control input. Vriable water volume (VWV) was control by Fuzzy adaptive control (FA) combined with proportional integral derivative (PID) control algorithms (FA-PID). Computational simulations of two different control algorithms PID and FA-PID control were carried out in toolbox Simulink of Matlab. The fuzzy parameters were carefully tuned to produce less oscillatory responses. The results showed that the system based on FA-PID control is capable of controlling the disturbance efficiently with less time lag and small error than PID control.