H-Bridge

These end up getting tricky to build discretely, but high power versions get costly.

I think DRV8701 allows you to mount your own mosfets, which may allow me to increase the power capacity. look for "Full-Bridge Gate Driver" or "full-bridge pre-driver"

http://www.modularcircuits.com/blog/articles/h-bridge-secrets/

Discrete Driver

The bridge itself is pretty simple, but driving it is awful.

Low side is fairly easy. At low voltages, a BJT can be used. At higher voltages, we need to raise the gate voltage because it should only be 10-20v lower than the high side.

The high side driver is a pain because high side N-Chan driving is always a pain. As long as it will never go high for long periods, a bootstrap cap can be used.

VFD

3 half bridges can be used to create a VFD for a 3 phase induction motor.