Zeta converter based power supply for HB-LED lamp with universal input

Abstract

This paper deals with power quality improvement aspects of power supply for High Brightness Light Emitting Diode (HB-LED) lamp operating with universal AC mains. The proposed LED driver consists of a PFC (power factor corrected) Zeta converter which operates in discontinuous conduction mode (DCM) with universal AC mains. The proper design, modeling and simulation of 27 W LED (twenty seven 1W LEDs connected in series) driver are carried out in MATLAB/Simulink software for a rated voltage of 220V, 50 Hz. The constant lamp voltage is achieved using the voltage follower control scheme for retrofit applications. Each LED has a forward voltage of 3V and forward current of 350mA. The power quality indices are calculated such as power factor (PF), distortion factor (DF), displacement power factor (DPF), crest factor (CF) and total harmonic distortion of AC mains current (THDi) to study the performance of improved power quality based LED lamp driver. The harmonic contents of input current and input power factor are as per the compliance of mandatory regulation of International Electrotechnical Commission (IEC) 61000-3-2:2004.