An energy efficient 48Vdc bipolar ELVDC LED lighting system in a high-rise building

This paper discusses an energy-efficient LED lighting distribution system in high-rise buildings based on 48Vdc bipolar ELVDC distribution nano-grid fed from a centralized AC/DC converter. The paper first introduces the LED lighting system performances and its associated challenges. It then introduces the preference for ELVDC distribution system in the built environment. The paper then presents the mathematical model of the two different ELVDC distribution systems: the unipolar and the bipolar systems and their associated electrical component models. An approximated analysis was done using a constant power load model on the two distribution systems with voltage drop and power loss as the main indices. Simulations were carried out to determine the voltage level and system efficiencies at each node point. Experimental results of the two ELVDC LED lighting systems are verified and are compared with theoretical results. The 48Vdc bipolar ELVDC distribution system has reduced voltage drop and better system efficiency compared to the 24Vdc unipolar system.