Discontinuous Current Mode Modeling and Zero Current Switching of Flyback Converter

Rustam Kumar, Chih-Chiang Wu, Ching-Yao Liu, Yu-Lin Hsiao, Wei-Hua Chieng and Edward-Yi Chang
Additional contact information
Rustam Kumar: Department of Mechanical Engineering, College of Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan
Chih-Chiang Wu: Mechanical and Mechatronics Systems Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan
Ching-Yao Liu: Department of Mechanical Engineering, College of Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan
Yu-Lin Hsiao: Hsinchu Science Park Branch, Elite Advanced Laser Corporation, Miaoli 35053, Taiwan
Wei-Hua Chieng: Department of Mechanical Engineering, College of Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan
Edward-Yi Chang: Department of Material Science and Engineering, College of Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan

Energies, 2021, vol. 14, issue 18, 1-23

Abstract: The flyback converters are widely used in low power applications. The switch typically requires 600 V breakdown voltage in order to perform large step-down voltage. Thus, slight variation on the switch control can either permanently damage the switch or decrease the efficiency of the power conversion. In order to achieve higher power efficiency, the previous literature suggested operating the flyback converter in the discontinuous current mode (DCM). It is then required to understand the critical conditions of the DCM through analyzing the dynamic behavior and discontinuous current mechanism. This paper started from the current waveform analyses, proceeded to the derivation of zero current switching (ZCS) formulation, and finally reached the necessary conditions for the DCM. The entire DCM operation was divided into three phases that subsequently affect the result of the zero voltage switching (ZVS) and then to the ZCS. The experiment shows a power efficiency of over 96% when the output power is around 65 W. The switch used in this paper is a Gallium Nitride High-Electron-Mobility Transistor (GaN HEMT) that is advantageous at the high breakdown voltage up to 800 V. The important findings from the experiments include that the output power increases with the increasing input DC voltage and the duty cycle is rather linearly decreasing with the increasing switching frequency when both the zero voltage switching (ZVS) and ZCS conditions are satisfied simultaneously.

Keywords: flyback; discontinuous current mode; GaN HEMT (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (7)

Downloads: (external link)
https://www.mdpi.com/1996-1073/14/18/5996/pdf (application/pdf)
https://www.mdpi.com/1996-1073/14/18/5996/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:14:y:2021:i:18:p:5996-:d:639971

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().