Open AccessSelf‐oscillating current‐fed inverter with low switching loss for wireless power transfer
Author(s) -
Kwon Y.,
Ahn D.
Publication year - 2017
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2017.0760
Subject(s) - capacitor , mosfet , duty cycle , inverter , antiparallel (mathematics) , electrical engineering , wireless power transfer , topology (electrical circuits) , voltage , inductor , physics , engineering , electromagnetic coil , transistor , magnetic field , quantum mechanics
A zero‐voltage switching topology for self‐oscillating current‐fed resonant inverter for wireless power transfer application is proposed. The drawback of conventional floating‐capacitor connection between two differential MOSFET outputs is revealed. It turns out that the conventional connection causes severe switching loss because the MOSFET voltage has duty cycle >50%, while the current has an exact 50% duty cycle to sustain the self‐oscillation. To solve the issue, the proposed self‐oscillating inverter equips with two antiparallel diodes and two resonance capacitors between MOSFET output and ground, while the floating capacitor is removed. This allows dead‐time of MOSFETs and zero‐voltage switching, leading to significant reduction in switching loss. The operation and efficiency of the proposed circuit is demonstrated by simulation and measurements.