Optimal design of high frequency high efficiency and high‐power density DC–DC power module based on GaN

Abstract

Abstract This paper develops a railway power module with wide range voltage (dc 60—dc 160 V) input and constant voltage output (24 V/10 A) . The power module adopts a two‐stage topology structure to realize voltage conversion. Use the most advanced GaN (gallium nitride) as the main power switching devices. The first stage circuit architecture uses a two‐phase interleaved buck converter convert the wide range input voltage into a constant intermediate bus voltage (48 V) through closed‐loop control, and then the LLC resonant converter converts the intermediate bus voltage (dc 48 V) into a constant output voltage (dc 24 V) through open‐loop control, and realize the primary side and secondary side dc 3000 V electrical isolation. This article from the circuit topology, the power devices selection, buck converter magnetic integrated coupling inductance design, planar magnetic integration LLC resonant transformer optimization design has carried on the detailed discuss and analysis. All circuits are integrated in a standard quarter power brick module, the final prototype can reach 96.1% peak efficiency, the power density can reach 185 W/in.3.