Aman Jha

Landsman based PFC with PWM dimming for high brightness LED driver

This paper presents a Landsman converter fed power factor correction (PFC) based light emitting diode (LED) driver. The application is targeted for high brightness (HB) projection application with brightness control of high brightness red-green-blue (HB-RGB) LED. A pulse width modulation (PWM) technique is used for current control to achieve effective brightness required without compromising the efficiency (overall 85%). This PFC converter is used to feed a dual output flyback DC-DC converter which supplies power to the forced cooling unit and the LED module with galvanic isolation. The brightness control of LED is performed by synchronous buck converter via current modulation. The PFC converter is designed to operate in discontinuous input inductor current mode for inherent PFC at universal AC mains. A prototype of the proposed PFC 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 (90-265V) with brightness control. The power quality parameters are found within acceptable range of international harmonic standard IEC 61000-3-2 for universal AC mains.

Power quality improvement using CSC converter for high power LED driver

In this paper canonical switching cell (CSC) converter is used for power quality improvement in high-brightness (HB) light emitting diode (LED) module. This application is targeted for high power projection application for full brightness control of HB red-green-blue (RGB) LED module. PWM technique for current control is used for effective brightness control of LED driver. This PFC CSC converter is used to feed flyback DC-DC converters which supplies power to the coolant pump and the LED module. Synchronous buck converters are used for brightness control via PWM control of the LED string. The design of CSC PFC converter is in discontinuous conduction mode (DCM) for natural PFC. The hardware prototype of the proposed LED driver is developed for experimental verifications. It is evaluated over a universal input voltage with brightness control and unity power factor.

A PFC modified-Landsman converter based PWM-Dimmable RGB HB-LED driver for large area projection applications

This paper presents a modified-Landsman converter fed power factor correction (PFC) based light emitting diode (LED) driver. The application is targeted for high brightness (HB) projection application with brightness control of high brightness red-green-blue (HB-RGB) LED. A pulse width modulation (PWM) technique is used for current control to achieve brightness control of LED driver without compromising the efficiency. The modified-Landsman PFC converter is used to feed a dual output flyback DC-DC converter which supplies power to the forced cooling unit and the LED module with galvanic isolation. The brightness control of LED is performed by synchronous-buck converter. The PFC based modified-Landsman converter is designed to operate in discontinuous output inductor current mode for PFC at universal AC mains. A hardware prototype of the proposed LED driver is developed for experimental verification. The performance of the proposed driver is evaluated at full and light load condition for universal AC mains (90–265V) over a full range of brightness control. The power quality indices are found within the acceptable limits of international harmonic power quality standard IEC 61000-3-2 for universal AC mains.

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

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.

Bridgeless canonical switching cell based PFC converter for high power LED driver

Abstract This paper deals with power factor correction (PFC) in high-brightness (HB) light emitting diode (LED) module using a bridgeless canonical switching cell (BL-CSC) converter. This application is designed for large area LED projection application with full brightness control of HB red-green-blue LED module. A PWM technique is used for brightness control of LED driver. This BL-CSC PFC converter is used to feed dual flyback DC-DC converter which supplies power to the cooling unit and the LED module with galvanic isolation. Synchronous buck converters are used for brightness control using PWM dimming technique of the multiple LED strings. The BL-CSC PFC converter is designed for discontinuous inductor current mode operation to provide natural PFC at AC mains. A working prototype of the proposed LED driver is developed for experimental verifications. The performance parameters of the proposed HB LED driver is evaluated for a full brightness control capability with high power factor at universal input AC (90–265 V). The improved power quality parameters observed at AC mains are found within the acceptable limits of international power quality standard IEC 61000-3-2.

SEPIC PFC converter fed LED driver

This paper presents a single ended primary inductance converter (SEPIC) fed power factor correction (PFC) based light emitting diode (LED) driver. The application is needed for high brightness LED control for projection application. A pulse width modulation (PWM) scheme is used for LED brightness control. In order to control LED with better power quality a SEPIC converter is proposed as a power factor corrector which works in discontinuous output inductor current mode (DICM).The SEPIC PFC converter feeds constant dc voltage to bi-flyback DC-DC converter. The bi-flyback DC-DC converter supplies constant low voltage with isolation required to the forced cooling unit and the synchronous buck based constant current multi-string LED driving unit. The forced cooling unit is introduced to control LED temperature near ambient to increase life of LED and matching color. The synchronous buck based LED driver is used to control LED brightness and fulfills the constant current for LED driving. A prototype of the proposed 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 V-265 V). The PFC and total harmonic distortion (THD) are found within acceptable ranges of international harmonic standard IEC 61000-3-2.

Bridgeless buck-boost PFC converter for multistring LED driver

In this paper, a bridgeless buck-boost converter is used for power factor correction (PFC) of low voltage high current (LVHC) multi-string light emitting diode (LED) driver. This is a design for an application in large area LED lighting with illumination modulation. A multi-mode LED dimming technique is used for lighting control. The BL buck-boost PFC converter feeds power to isolated flyback DC-DC converter. The regulated low voltage from a flyback converter is a source power to the synchronous buck converters for multi-string LED driver and forced cooling system for LED junction. The design of the inductor of BL-buck-boost PFC converter is based on discontinuous inductor current mode (DICM), which provides good PFC at low cost. A prototype is designed and tested for a LED driver. The performance of proposed HB LED driver is evaluated for a full brightness control capability. The measured harmonic parameters are found lower than range set for lighting by IEC 61000-3-2 Class C.

Cuk PFC converter for high brightness LED driver with brightness control

This paper presents a Cuk converter fed power factor correction (PFC) based light emitting diode (LED) driver. It is designed for high brightness (HB) low voltage LED driving. A pulse width modulation (PWM) technique is used for current control to achieve different LED brightness level. The PFC Cuk converter is used to feed a dual output flyback DC-DC converter which supplies power to the forced cooling unit and the LED module. The Cuk converter design is based on energy storage element, inductor to run in discontinuous current mode for PFC without current sensing. A prototype of the proposed Cuk converter LED driver is developed and power quality parameters are evaluated at full and LED dimmed conditions for universal AC mains (90–265V). The power factor and harmonic distortion measured value are within acceptable ranges of international harmonic standard IEC 61000–3–2 Class C.

Modified bridgeless landsman PFC converter for LED driver

This paper presents a modified bridgeless Landsman converter-fed power factor correction (PFC) for light emitting diode (LED) driver. The application is targeted for high brightness (HB) projection applications with brightness control of high brightness red-green-blue (HB-RGB) LEDs. The pulse width modulation (PWM) technique is used for current control to achieve effective brightness control of LED driver without compromising the efficiency. The modified BL- Landsman PFC converter is used to feed a dual flyback DC-DC converter which supplies power to the forced LED cooling unit and the LED lighting module with a galvanic isolation. The brightness control of LED is performed by synchronous-buck converter with current modulation. The proposed PFC based modified BL- Landsman converter design is based on discontinuous conduction mode of output inductor current for high power factor (PF). A hardware prototype of the LED driver is verified experimentally. The proposed LED driver performance evaluation at full and light load conditions is good for universal AC mains (90V-265V). The power quality parameters measured with calibrated instruments are within the acceptable limits of standard IEC 61000-3-2 Class C for lighting systems.