High Power Factor Light-emitting Diode Driver on Digital Signal Processor Without Electrolytic Capacitor for High-power Lighting

Abstract

Abstract—Electrolytic capacitor is a key factor that limits the life-time of the driver in a high-power light-emitting diode (LED) lighting. This article presents a high-power LED lighting driver on a digital signal processor without an electrolytic capacitor. The driver is composed of three stage circuits. The first stage is the boost power factor correction converter to achieve a high power factor. As it does not use an electrolytic capacitor, the output voltage ripple is larger, which directly affects the overall performance of the LED driver. Consequently, it must be optimized through the second and third stages. The second stage is the two-output LLC (Double inductance and capacitance) resonant converter, which is driven by a digital signal processor. This stage provides galvanic isolation and reduces voltage. The third stage is the two-input buck converter based on digital signal processor control that reduces the low-frequency ripple generated from the first two stages. Moreover, the regulation of each LED string current is achieved at this stage. The simulation and experimental results show that this LED lighting driver can achieve a high power factor and good constant current characteristics.

Keywords:

• High power factor
• electrolytic capacitor
• without electrolytic capacitor
• high-power lighting
• light-emitting diode driver
• digital signal processor
• digital control
• LLC resonant converter
• two-input buck converter

Additional information

Notes on contributors

Yong Chen

Yong Chen was born in Sichuan Province, China, in 1977. He received his B.S. in automation from Taiyuan University of Science and Technology, Taiyuan, Shanxi, in 2001; his M.S. in control theory and control engineering from Guangxi University, Nanning, Guangxi, in 2004; and his Ph.D. in control theory and control engineering from Chongqing University, Chongqing, in 2007. He was visiting scholar in the Centre for Energy Technology, The University of Adelaide, in 2013. He is currently working as an assistant professor and Ph.D. director in the School of Energy Science and Engineering. His current research interests include power electronics, servo control, energy control, and LED technology.

Jun Zhou

Jun Zhou was born in Chengdu City, Sichuan, in 1988. He received his B.S. in agricultural electrification and automation from Sichuan Agricultural University, Nan chong, Sichuan, in 2011, and his M.S. in electrical engineering at School of Energy Science and Engineering, UESTC, Cheng du, Sichuan, in 2014. He is currently working at AVIC Chengdu Aircraft Industrial CO.,LTD. His research interests include power electronics, LED driver circuits, PFC, and soft switching technology.

Eric Hu

Eric Hu received his B.S. in mechanical engineering from Zhejiang University, Zhejiang, China, in 1984; his M.S. in energy technology from Beijing Solar Energy Research Inst,China, in 1987; and his Ph.D. in the engineering program in energy technology from Asian Institute of Technology, Bangkok, Thailand, in 1992. He is currently working as an associate professor of sustainable energy engineering at the School of Mechanical Engineering, University of Adelaide. He has been working in energy engineering areas, including energy efficiencies for industrial process and solar thermal applications.