Zeta converter for power quality improvement for multi-string LED driver

Abstract

This paper presents a Zeta converter fed power factor correction (PFC) for high power light emitting diode (LED) driver. The application is targeted for multiple string red-green-blue (RGB) LED drivers with lumen control. A pulse width modulation (PWM) technique is used for light output control to achieve required light without compromising the efficiency. The Zeta converter is used to feed a bi-flyback DC-DC converter which supplies power to the synchronous buck based constant current switching regulator and PMDC motor required for forced cooling of LED module. The proposed converter designed for discontinuous output inductor current mode for PFC at universal AC mains at entire load regulation. The developed prototype of the proposed LED driver is experimentally verified. The power quality parameters of the proposed LED driver are evaluated at rated and light load conditions for universal AC mains (90-265V) with lumen control. The power quality parameters are measured and found acceptable ranges of international harmonic standard.