A Totem Pole PFC Control Based on Dynamic Root Locus with Wide Output Voltage Range and Low THD

The single-stage totem pole power factor correction (PFC) circuit is widely adopted as the front-end topology for on-board chargers (OBC) due to its high power factor (PF) and simplified structure. However, traditional control methods are inadequate for PFC control under a wide range of operating conditions. To address this challenge, this paper establishes a small signal model of the totem pole PFC current inner-loop and introduces a PI control method based on dynamic root locus (DRL-PI). Experimental results on a 3 kW platform show that compared with traditional fixed parameter control, the proposed control method reduces the estimated total harmonic distortion (THD) by 0.74% in constant resistance experiment and 3.36% in constant voltage experiment.