Valley skipping compensation for low THD in Constant-On-Time Control for PFC Pre-regulators: Implementation and Performance

摘要

The paper focuses on an optimization of the Constant On Time (COT) control for boost PFC in order to compensate the effect of valley skipping to achieve a better THD. The optimization is an improvement of the enhanced COT, a modified version of standard COT. The algorithms, the equations and digital implementation are detailed for the new method. The comparison of the THD with physical measurement based on real implementation are shown considering the optimized algorithm and the enhanced COT (eCOT). The comparison demonstrates the performance improvement in terms of THD at medium and low power.