Analysis of a high power COB led light source driven by offline double-stage PFC converter

This work presents a novel method to perform high-luminous flux LED (light emitting diode) lighting. The technique comprises high current COB (chip-on-board) LEDs while their features and main parameters are properly studied in this paper. Furthermore, a PET (photo-electro-thermal) modeling is presented and evaluated considering experimental validations. In order to drive this high power COB LED, a two-stage topology has been chosen aiming minimum capacitance associated with high dc voltage bus. The first stage comprises a front-end PFC (power factor correction) boost pre-regulator operating in CCM (continuous conduction mode) whereas the second stage concerns an interleaved CCM buck structure in order to minimize current stresses in switches by sharing the rated current properly. Besides, simulation results are carried out and analyzed in order to obtain high power factor, low THD
i
(total input current harmonic distortion) and proper COB driving. Moreover, power quality results are presented aiming driver compliance with the 61000-3-2 C-Class international standard.