Adaptive dimming scheme based daylight pipe integrated indoor lighting system under Perez All-weather sky model

An adaptive dimming scheme is proposed for a daylight pipe(DLP) integrated indoor general lighting system to maintain the desired illuminance level and uniformity of light distribution on horizontal working plane. The proposed dimming scheme simultaneously controls the lumen delivery from both DLPs and lamps. The daylight delivery of the DLPs is adjusted by a control logic based on dynamic outdoor light level whereas lamps follow separate control logic based on dynamic daylight illuminance distribution on working plane. Electrochromic(EC) glass sheet is used with emitter of DLPs to control its lumen delivery whereas lamps are driven by dimmable electronic ballasts. The outdoor daylight level is obtained with Perez All-weather sky model by utilizing measured solar radiation database. The proposed control scheme is implemented through a developed program in Matlab environment and its performance is tested by a sample indoor space at Kolkata. Simulation results are satisfactory in terms of illuminance level, its distribution and indicates significant amount of energy saving of the order of 80% for the duration 8AM to 5PM.