Small Signal Modeling and Control Design for New Extended Duty Ratio, Interleaved Multiphase Synchronous Buck Converter

This paper presents large signal and small signal average models and a control structure for a new extended duty ratio, multiphase, synchronous buck converter. This recently introduced topology produces an increase in duty ratio by a factor 2 and a significant reduction in output current ripple. An intrinsic current balancing mechanism, a new overlapping steady state mode of operation, and an improved interleaving pattern are examined in this paper. The proposed modeling and control design methodologies are applied to a 12 V-1.2 V/40 A, 400 kHz, four-phase prototype