Design and Implementation of Interleaved Quasi-Resonant DC-DC Flyback Converter

This paper presents the interleaved quasi-resonant (QR) DC-DC flyback converter, which uses two parallelconnection DC-DC flyback converters. The interleaved technique is used to control the active switches of the two flyback converters. Also, the active switches are turned on at voltagevalley condition to reduce switching losses. Thus, this converter can achieve large output power, low output-current ripple, and high efficiency. The operating principle is discussed. Finally, a prototype circuit with input voltage 300 400 V, output voltage 24 V, and output current 8.33 A is implemented to verify the performance.