Study on Zero-Crossing Current Distortion in Interleaved Totem-Pole PFC Converters

Under continuous conduction mode (CCM), interleaved totem-pole power factor correction (PFC) converters exhibit input current distortion at the zero-crossing point of AC input voltage. To address this issue, this paper first analyzes the mechanism of zero-crossing distortion and proposes an improved control strategy. The approach divides the zero-crossing region into dual control phases, implementing complementary soft-switching for high-frequency bridge switches. Simultaneously, the output of the current-loop controller drives line-frequency switches to compensate for phase delay caused by power inductors. A 220-V AC input, 400–600-V DC output, 6.6-kW full-load Simulink simulation platform is established for validation. Experimental results demonstrate that the proposed strategy effectively reduces current distortion at zero-crossing points, decreasing total input current total harmonic distortion (THD) by 1.54% and enhancing both the full-load power factor and system efficiency.