High Step Down Dual Output Light Emitting Diode Driver
A conventional power factor correction (PFC) based light emitting diode (LED) drivers composed of two stage DC DC conversions has several drawbacks such as; increased system size due to more component count, less efficiency and complex control etc. The grid powered LED lighting demand for high step down conversion because the required voltage level of LED light is very less. Thus, this work proposes a one switch dual output (OSDO) coupled inductor buck (CIB) LED driver with current auto balancing. OSDO CIB converter can eliminate most of the drawbacks of conventional counterparts. The proposed OSDO CIB converter can provide various benefits such as; compact size, high efficiency, less total harmonic distortion (THD) simple control, and significant reduction in device voltage/current rating due to coupled inductors. The converter is designed with discontinuous conduction mode (DCM) of operation in order to achieve in phase current and voltage, high power factor (PF) and a low THD. This paper mainly emphasized on detailed operating modes and steady state analysis of proposed converter. Further, proto type of the converter is built and experimental validations are presented.