Digital control device of active clamping flyback AC-DC converter based on gallium nitride device

• Main Authors: HE LENIAN, ZHU QINWEI, XI JIANXIONG, GU DONGLIE, HUANG FEIMING
• Format: Patent
• Language: Chinese; English
• Published: 07.01.2020
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION

The invention discloses a digital control device of an active clamping flyback AC-DC converter based on a gallium nitride device, replaces a traditional silicon-based device with a gallium nitride device with a higher quality factor, adds a clamping tube and a clamping capacitor with controllable power to a flyback circuit, and utilizes an active clamping circuit for replacing a passive absorptioncircuit. The digital control device samples the information such as the peak current, an auxiliary winding voltage, an output feedback voltage and the like, digitally modulates output voltage changeand the dead time between a main power tube and a clamping tube, clamps the maximum reverse current of a primary side current, maintains the main power tube to be just in zero-voltage conduction, andovercomes the defect of high reverse conduction loss of a gallium nitride device. A light load control scheme is optimized, so zero-voltage conduction of the two power tubes can be realized under anycondition. Due to soft switc