Novel Hybrid Switching Control Technique for Light Load Efficiency Improvement of GaN-based Totem Pole Power Factor Corrector

A novel hybrid switching control technique for Totem Pole Power Factor Corrector (PFC) is proposed in this paper. The proposed hybrid switching control technique significantly improves the light load efficiency of PFC. In the discontinuous conduction mode region in continuous conduction mode, the proposed “quasi synchronous rectification” control is used to significantly reduce the conduction loss of D-GaN MOSFET during the inductor demagnetizing period while avoiding the reversal inductor current as the inductor current becomes negative. The specifications of the totem pole power factor corrector developed in include: rated output power of 1200 W, input voltage AC 230 Vrms, output voltage DC 400 V, and switching frequency 65 kHz. The experimental results show that the overall efficiency is higher than 98.7% and the highest efficiency is 99.338% at 10% load which is improved by around 2% as compared with that for conventional approach.