High power factor and low total harmonics distortion using critical conduction mode boost converter-fed light-emitting diode driver

Abstract

Summary This article presents a critical conduction mode (CRM)–based power factor correction (PFC) converter for multistring light-emitting diode (LED) driver. The application is targeted for high power projection application with brightness control of red-green-blue LED module. A pulse width modulation (PWM) technique is used for lighting control to achieve required brightness without compromising the efficiency (overall 82%) and power quality. The CRM boost PFC converter is used to feed a dual output flyback DC-DC converter, which supplies power to the forced cooling unit and the LED modules with galvanic isolation. The brightness control of LED is performed by synchronous buck converter using current PWM modulation. The CRM boost converter–based PFC converter is designed to operate in critical inductor current mode at universal AC mains. A prototype of proposed PFC converter–based LED driver is developed and experimentally verified. The power quality parameters of the proposed LED driver are evaluated at rated and light load conditions for universal AC mains (90–265 V) with brightness control. The power quality parameters are found within acceptable ranges of international harmonic standard IEC 61000-3-2 Class C for lighting systems.