Fuzzy Logic Controller Based Bridgeless Isolated Interleaved Zeta Converter for LED Lamp Driver Application

Abstract

In recent times, High-Brightness Light Emitting Diodes (HB-LEDs) are developing rapidly and it is confirmed to be the future development in lighting not only because of their high efficiency and high reliability, however also because of their other exceptional features: chromatic variety, shock and vibration resistance, etc. In this paper, a Bridgeless (BL) Isolated Interleaved Zeta Converter is proposed for the purpose of reducing the diode failures or losses, the value of output ripples also gets decreased. The proposed BL isolated interleaved zeta converter operating in Discontinuous Conduction Mode (DCM) is used for controlling the brightness of LED Driver with inherent PFC at ac mains using single voltage sensor. The fuzzy logic controller (FLC) is used to adjust the Modulation Index of the voltage controller in order to improve the dynamic response of LED Lamp driver. Based on the error of converter output voltage, FLC is designed to select the optimum Modulation Index of the voltage controller. The proposed LED driver is simulated to achieve a unity power factor at ac mains for a wide range of voltage control and supply voltage fluctuations.