A new phase shedding scheme for improved transient behavior of interleaved Boost PFC converters

Abstract

This paper proposes a new phase shedding scheme for interleaved Boost PFC converter to improve the light load efficiency. In the proposed scheme, the power level in the slave channels is reduced linearly as the output loading drops for optimization of light load efficiency. The new scheme also prevents the PFC slaves from switching between the ON and OFF states immediately after phase shedding, thereby improving the load transient behavior of the system. The proposed scheme is verified on a universal input, 390V output, 2.5KW 3-phase interleaved Continuous Conduction Mode (CCM) Boost power factor correction (PFC) converter and experimental results are presented to demonstrate the improved light load efficiency and output voltage stability during load transient.