Professor Robert Pilawa-Podgurski from the University of Illinois gave a very good webinar on Tackling the Little Box Challenge - New circuit architectures to achieve a 216 W/in^3 power density 2 kW inverter
The Little Box Challenge was a contest sponsored by Google and the IEEE to build an 2 kW 400 VDC to 240 VAC single phase inverter with at least a 50 W per cubic inch power density. The contest had a $1,000,000 prize. Over a hundred teams entered and eighteen teams were selected to submit their design for testing at NREL. Three teams passed the test. The webinar describes his teams efforts to build a inverter for the challenge.