Reverse Conduction Loss and $\left(\frac{d v}{d t}\right)$ Induced False Triggering Protection of GaN-HFET Based Power Converter for EV Charging

Enhancement mode GaN (e-GaN) and cascode GaN HFET both are capable of 3<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> quadrant operation where e-GaN HFET has zero <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${Q}_{{r}{r}}$</tex> and cascode GaN HFET has small <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${Q}_{{r}{r}}$</tex> (less than MOSFET). These makes negligible switching loss using these devices in power converter (PC) but larger threshold voltage <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$({V}_{{t}{h}}\approx-6{V}$</tex> for e-GaN and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${V}_{{t} {h}}\approx-2{V}$</tex> for cascode GaN HFET) in 3<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> quadrant and higher reverse resistance creates extra reverse conduction loss. Again, bootstrap capacitor-based driver for both these devices creates <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\left(\frac{d v}{d t}\right)$</tex> induced false triggering at high side e-GaN-HFET with increased loading and dead time. In this work reverse conduction loss comparison is performed on both MOSFET (V≈0.7 V) and GaN-HFET based 600W LLC resonant converter used for EV charging. <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\left(\frac{d v}{d t}\right)$</tex> induced false triggering prevention method is also proposed.