Single stage dual purpose offline HB-LED driver with power factor correction for illumination and visible light communication

In this paper a dual purpose offline LED driver using Single Stage Buck-Boost Buck (S²-B³) converter for illumination control and Visible Light Communications (VLC) with Power Factor Correction (PFC) is presented. The (S²-B³) converter is designed to operate buck-boost section in Discontinuous Conduction Mode (DCM) with constant duty ratio to provide inherent power factor correction (PFC). The buck section of the converter is operated in Continuous Conduction Mode (CCM) with Average Current Mode Control (ACMC) to realize a constant current source for LED loads. LEDs when switched ON and OFF with megahertz frequencies will facilitate VLC along with illumination. Data transfer and illumination control are achieved through Variable Pulse Position Modulation (VPPM) and high frequency dimming respectively. Simulation and experimental results of the proposed dual purpose converter with PFC for a 500 lm output with 110/120V AC input are presented.