Development of an air-conditioning control system responsive to location and intensity of heat source using thermal sensors

Abstract

In this project, a control system for a two-fan ventilation model that is responsive to the location and intensity of a heat source using a thermal sensor was designed. Making use of the sixteen sensing elements in an infrared sensor, a weighting that correlated with the distance between the sensing element and the fan was assigned to the temperature reading of each sensing element. The average weighted temperature was then used as the parameter to control the fan voltage. A control program was written in Arduino IDE to control the voltage of two fans. To facilitate the real-time monitoring of the heat source and the fan status, a processing program was written in Java to display the real-time data in colour boxes. The control model and the processing program were tested by a series of experiments using a lamp to simulate a heat source. Results proved that the average weighted temperature is a suitable parameter, and the proposed model satisfactorily controls the fans to operate at optimal voltage/speed in response to the temperature and location of the heat source in a fully automated and real-time manner. The system provides a simple, user-friendly and economical design applicable to airconditioning and ventilation systems with a high potential of energy-saving.