WAN Converter: A Family of Multicell PWM Converter with All-in-One Magnetics

This paper presents a family of PWM converters-the WAN Converter-with matrix coupled 'all-in-one' mag-netics for wide operation range dc-dc applications. The WAN converter comprises multiple PWM converter cells driving a single magnetic component with matrix coupling. The matrix coupled multi-winding magnetics miniaturizes the dc inductive energy storage and significantly reduces the loss and volume of magnetic components. By applying multiphase interleaving, the inductor current ripple can be greatly decreased while maintaining fast transient speed. Topologies with matrix coupled magnetics achieve higher efficiency, higher power density, and faster dynamic response than with discrete magnetic components. To validate the WAN topology and matrix coupling concept, a 1 V-to-5 V input, 1 V-to-5 V output, four-phase SEPIC-based WAN prototype with a planar PCB matrix coupled inductor was designed and tested. PCB windings are optimized to reduce the ac resistance. The WAN prototype can support load current up to 185 A at 5 V-to-1 V voltage conversion with a maximum power density over 470 W/in3. Compared to discrete commercial inductors, the matrix coupled inductor has a 4x smaller size and 9x faster transient speed with similar current ripple and rating.