کنفرانس مهندسی برق ایران

صفحه اصلی / سی و دومین کنفرانس بین المللی مهندسی برق

Improving ZVS performance in phase shift LLC converter using variable magnetizing inductor for wide input/output voltage range

نویسندگان :

Saeed Ramezani darvish¹ Kioumars Shahriyari² Salar Sadeghian³ Adib Abrishamifar⁴

1- دانشگاه علم و صنعت ایران 2- دانشگاه علم و صنعت ایران 3- دانشگاه علم و صنعت ایران 4- دانشگاه علم و صنعت ایران

کلمات کلیدی :

phase shift LLC converter،variable magnetizing inductor،wide input and output voltage range

چکیده :

LLC converters face challenges in applications with a wide range of input voltages, as they need to vary the switching frequency (fsw) significantly to achieve the desired voltage gain. This leads to issues such as complicated design of magnetic elements and increased power dissipation. Phase-shift modulation (PSM) can solve these issues, but it has a drawback of losing zero-voltage switching (ZVS) in the lagging-leg switches when the phase-shift angle (φ) is large, which results in high switching losses. Moreover, due to the large phase angle, there is a long period of time in one cycle where no energy is delivered to the load, which causes high circulation loss. To ensure ZVS operation at large phase angles, a combination of PSM and variable magnetizing inductor (MI) is proposed in this article. By optimally adjusting the value of the MI at all phase angles, not only ZVS operation are provided for lagging switches but also reduces circulating current, which ultimately reduces conduction losses. The Usefulness of the suggested control strategy is confirmed by simulation results.