Efficient High Step-Up Operation in Boost Converters Based on Impulse Rectification

Abstract

Conventional boost converters, while having a high level of simplicity and robustness, are known to have a poor efficiency at high step-up regime. More complicated topologies have been extensively explored to increase the step-up ratio while keeping a high-efficiency, however, an efficient regulated dc-dc power conversion at high step-up regime still remains a challenge. In this work we demonstrate fully soft-switched operation of boost converters based on impulse rectification, which results in an efficient power conversion at very high step-up regime. Contrary to the conventional analysis of boost converters which seeks to minimize conduction and switching losses, our approach considers reactive power as the key parameter limiting efficiency. A theoretical basis for this operation mode enabled an appropriate design resulting in power conversion efficiencies above 90% for voltage gain values of 5, 10, 25, and 50, with a peak efficiency of 97%. The guidelines to design boost converters based on the proposed approach are discussed. The simplicity and high performance of this approach opens new avenues in designing regulated dc-dc converters with a high step-up.

Comparison of Wide-Band-Gap Technologies for Soft-Switching Losses at High Frequencies

“…DISCUSSION WBG field-effect transistors based on GaN and SiC enable fast switching speeds for high frequencies, where the elimination of switching losses, especially at turn-ON transients, becomes crucial [9], [23], [26]. Topologies such as phase-shifted full-bridge (PSFB) [12], dual-active-bridge (DAB) [5] and soft-switched boost converters [11] take advantage of ZVS for efficient high-frequency operation. The presented loss measurements in this letter emulate a ZVS operating condition, enabling a detailed comparison of the overall soft-switching losses.…”

“…HE reduced input capacitance (CISS) and ON Resistance (RDS(ON)) in wide-band-gap (WBG) transistors enable their efficient operation at high frequencies [1], [2], for instance, high-power-density dc-dc conversion [3]- [6], wireless power transfer and radio-frequency amplification [7], [8]. At such frequencies, soft-switched topologies, especially those designed for zero-voltage switching (ZVS), can potentially achieve high efficiencies [5], [9]- [11]. To that end, low levels of electromagnetic interference (EMI) and proper design of passive components, especially the magnetics, become crucial [5], [12], [13].…”

Calibration-Free Calorimeter for Sensitive Loss Measurements: Case of High-Frequency Inductors

“…Power converters based on WBG technologies can expose inductors to high-frequency currents or high-dv/dt voltage excitations [7], [8], [22], [23].…”

“…The emergence of high-performance wide-band-gap (WBG) technologies and high-quality passive components (e.g. high-frequency transformers and inductors) have enabled ultra-high efficiencies in high-frequency power conversion [1]- [8]. However, measuring high efficiencies electrically is prone to large errors due to insufficient measurement accuracies [9], [10].…”