A Novel Ambiance Changing Energy Saving Led Lighting System With Pfm Operated Zeta Converter

This study deals the design, simulation and implementation of an isolated Zeta converter based novel costeffective, dual-colored, step-dimming with power quality improvement at universal AC mains while operating the power factor correction (PFC) converter in Discontinuous Conduction Mode (DCM). The PFC Zeta converter is able to provide regulated output current to a string of LED load of 23 W and maintains the power quality indices within the requirements of IEC61000-3-2 for class C equipments with high level of efficiency. Moreover, to achieve cost benefit and size reduction, this converter utilizes reduced control circuitry for the emerging LED lighting solutions. A novel cost effective color changing is discussed with primary-side regulation (PSR) technique using an isolated Zeta converter. A prototype of the Zeta converter with color changing solution and step-dimming mechanism is implemented to evaluate the proposed approach. The overall power factor at full load condition is achieved around 0.98 and AC mains current THD as 7.15% with an efficiency of 85.56% at rated voltage of 220V.