Design of a LED street lighting system

LED technology has rapidly developed in recent years to the point that LEDs can be seriously considered for replacing conventional halogen and incandescent lamps in general illumination, e.g. street lighting. Before wide spread adoption of this technology can be embraced, there are a number of outstanding issues that need to be addressed. The opportunity is now available for the implementation of innovative concepts for heat transfer, thermal management, optimised LED power drivers and communication systems. This paper consists primarily of three parts. Firstly, current UK street lighting regulations and requirements are outlined, shortfalls are identified and highlighted. In the second part, thermal management of the LEDs and their drivers are detailed. It is imperative that the LEDs are kept within their maximum operating temperature to ensure maximum stated lifetime and performance. Finally the third part proposes suitable topologies for providing unity power factor and regulating current through the LED arrays.