Digital Fuzzy Current Controlled Light-Emitting Diode Driver with Power Factor Correction

This paper presents the design and development of a fuzzy peak current controlled (FPCC) single-stage single-phase nonisolated AC/DC high-power factor LED drive. The proposed controller includes a fuzzy logic controller (FLC) in the loop voltage and a peak current controller in the loop current for an integrated nonisolated LED driver to attain a high-power factor (PF). The proposed control avoids complexities related to nonlinearities of the converter. The control action is initially derived from a group of rules written in accordance with experience and intuitive reasoning. The proposed technique is realized using a DSP processor (TI-TMS320F2812), which is capable of executing a high number of instructions in one cycle. A 70 W, 350 mA LED driver operating with an input of 90 V-230 V, 50 Hz was designed and implemented using MATLAB/Simulink. The results of the driver are in accordance with international regulations. The steady-state and transient responses are validated experimentally.

Download Full-text

A Single-Stage High-Power-Factor Light-Emitting Diode (LED) Driver with Coupled Inductors for Streetlight Applications

Applied Sciences ◽

10.3390/app7020167 ◽

2017 ◽

Vol 7 (2) ◽

pp. 167 ◽

Cited By ~ 5

Author(s):

Chun-An Cheng ◽

Chien-Hsuan Chang ◽

Hung-Liang Cheng ◽

Ching-Hsien Tseng ◽

Tsung-Yuan Chung

Keyword(s):

Power Factor ◽

High Power ◽

Light Emitting Diode ◽

Single Stage ◽

Led Driver ◽

Light Emitting ◽

Coupled Inductors ◽

High Power Factor

Download Full-text

A High-Power-Factor Dimmable LED Driver with Integrated Boost Converter and Half-Bridge-Topology Converter

Applied Sciences ◽

10.3390/app10082775 ◽

2020 ◽

Vol 10 (8) ◽

pp. 2775

Author(s):

Hung-Liang Cheng ◽

Yong-Nong Chang ◽

Lain-Chyr Hwang ◽

Hau-Chen Yen ◽

Shun-Yu Chan ◽

...

Keyword(s):

Power Factor ◽

High Power ◽

Pulse Width Modulation ◽

Light Emitting Diode ◽

Current Mode ◽

Boost Converter ◽

Led Driver ◽

Zero Voltage Switching ◽

High Power Factor ◽

Integrated Boost

This paper proposes a dimmable light-emitting diode (LED) driver featuring a high power factor and zero-voltage switching on (ZVS). The circuit is obtained by integrating a boost converter and a dc-dc converter with half-bridge topology. The high power factor is achieved by operating the boost converter in discontinuous current mode (DCM). The LEDs are dimmed by the control scheme of asymmetrical pulse-width modulation (ASPWM). The developed circuit eliminates the inherited dc-offset current of the transformer in a conventional asymmetrical half-bridge converter by introducing a balance capacitor. Both active switches can operate at ZVS by freewheeling the boost inductor current and the transformer magnetizing current to discharge the energy stored in their parasitic capacitance. The circuit operation is analyzed in detailed, and mathematical equations are derived. Finally, a 115-W prototype circuit for driving high brightness LEDs was built and tested. The experimental results verify the feasibility of the proposed LED driver with satisfactory performance. It can achieve a high power factor and ZVS operation.

Download Full-text

A Novel Single-Switch Single-Stage LED Driver with Power Factor Correction and Current Balancing Capability

Electronics ◽

10.3390/electronics10111340 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1340

Author(s):

Yih-Her Yan ◽

Hung-Liang Cheng ◽

Chun-An Cheng ◽

Yong-Nong Chang ◽

Zong-Xun Wu

Keyword(s):

Power Factor ◽

High Power ◽

Pulse Width Modulation ◽

Power Factor Correction ◽

Harmonic Distortion ◽

Boost Converter ◽

Single Stage ◽

Led Driver ◽

Flyback Converter ◽

High Power Factor

A novel single-switch single-stage high power factor LED driver is proposed by integrating a flyback converter, a buck–boost converter and a current balance circuit. Only an active switch and a corresponding control circuit are used. The LED power can be adjusted by the control scheme of pulse–width modulation (PWM). The flyback converter performs the function of power factor correction (PFC), which is operated at discontinuous-current mode (DCM) to achieve unity power factor and low total current harmonic distortion (THDi). The buck–boost converter regulates the dc-link voltage to obtain smooth dc voltage for the LED. The current–balance circuit applies the principle of ampere-second balance of capacitors to obtain equal current in each LED string. The steady-state analyses for different operation modes is provided, and the mathematical equations for designing component parameters are conducted. Finally, a 90-W prototype circuit with three LED strings was built and tested. Experimental results show that the current in each LED string is indeed consistent. High power factor and low THDi can be achieved. LED power is regulated from 100% to 25% rated power. Satisfactory performance has proved the feasibility of this circuit.

Download Full-text