Open AccessHigh‐power‐density high‐efficiency LLC converter with an adjustable‐leakage‐inductance planar transformer for data centers
Author(s) -
He Peiwen,
Mallik Ayan,
Cooke Gary,
Khaligh Alireza
Publication year - 2019
Publication title -
iet power electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.637
H-Index - 77
eISSN - 1755-4543
pISSN - 1755-4535
DOI - 10.1049/iet-pel.2018.5299
Subject(s) - leakage inductance , galvanic isolation , electrical engineering , transformer , inductance , power density , converters , forward converter , switched mode power supply , engineering , materials science , boost converter , electronic engineering , voltage , power (physics) , physics , quantum mechanics
LLC converters can achieve high efficiency, high‐ power density, wide gain range, and galvanic isolation. This study presents a high‐power‐density and high‐efficiency LLC converter with an adjustable‐leakage‐inductance planar transformer for the DC–DC conversion in data center power supplies. A planar transformer with adjustable leakage inductance is modelled and developed to provide an accurate design for resonant frequency and voltage gain. A detailed power loss analysis is performed. Furthermore, a thermal model is provided to aid in heat sink design. GaN devices are used in the converter to achieve high‐switching frequency and low‐switching loss. A 450 kHz, 360–400 V DC input, 12 V DC output, 750 W LLC converter prototype with an adjustable‐leakage‐inductance planar transformer is built and tested. The power density of the system is 15.4 W/cm 3 including an auxiliary power supply. The peak efficiency of the overall system is over 95%.