Design and evaluation of a 28W solid state lighting system

Two solutions for twenty-eight watts solid state lighting system were performed. The first one using two cascaded stages (power factor correction and constant current source) and the second one is an integrated stage (power factor correction and constant current source integrated). For each solution the corresponding design methodology was developed and electrical performance was evaluated in terms of Power Factor (PF), Total Harmonic Distortion in current (THDI), electrical efficiency and current regulation. To reduce energy consumption for lighting concept is necessary to have systems that take advantage of electric power on a better way and also that not interfere with other equipment connected to the mains. Therefore it is important that the power supply of the lighting system have a high power factor and low total harmonic distortion in current.