Automatic Light Control System for Seminar Halls Using Fuzzy Logic

In any seminar/conference hall, whenever a speaker/presenter wants to switch over from projected presentation to board due to some audience query, a physical person is needed to monitor the speaker activity and then control the lights accordingly. Lighting generally consumes 25%-50% of total electricity consumption in such a building. The previous techniques had focused on power density control without considering the control reference value. Compared with conventional dimmer method, the proposed method does not cause any harmonics. If a person enters to the monitored area, the PIR sensors the person; this information is send to the MSP430 controller. After sensing the person, LDR checks the light intensity of that particular area, whether it is bright or dark. Depending on the LDR output, the lamp may be turned on / off or intensity can be controlled by using dimmer circuit. To obtain homogeneity of light intensity, a model of fuzzy logic control system is used. As output, this control system will change duty cycle of Pulse Width Modulation (PWM) which is used to control the illumination of Light Emitting Diode (LED) lamp .This automatically adjusts light brightness to a level that allows the user’s eyes to be comfortable. The proposed system is able to minimize the energy consumed for lighting in a room and can able to provide it efficiently.