A Fanless Operating Trans-Linked Interleaved 5 Kw Inverter Using SiC MOSFETs to Achieve 99% Power Conversion Efficiency

A trans-linked interleaved inverter using silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) achieves a power conversion efficiency (eta) of 99% at 5 kW and an optimum eta of 99.4% at 2 kW. Its trans-linked part is composed of two combined reactors: a first reactor, made of a low saturation magnetic flux density (B-s) material, has a rectangular ring shape to cancel magnetic fluxes flowing therein; a second reactor, which strides in the hole of the ring to collect the fluxes to form the leakage inductance, acts as the smoothing reactor in the inverter and accordingly possesses a high B, to increase the output current. This circuit topology along with the high-frequency switching capability of SiC MOSFETs leads to a lower inductance of the smoothing reactor, thereby sufficiently reducing the number of winding turns in the reactor so as to cut off the copper loss of the reactor to decrease total power loss.