Original poster: "Jimmy Hynes" <jphynes@xxxxxxxxx>
The voltage rating of the IGBTs is for when the devices are turned off. When the devices are turned on, there is virtually zero volts across the device. But yes, you could use 2000V rail-to-rail voltage with an h-bridge made of 1000V IGBTs, however there would be no margin.
Ummm... just one problem. You can't turn it on... When one IGBT is on, virtually all of the voltage drop is across the other IGBT (2000v), and it will surely blow. The no margin rail to rail voltage for a H bridge that actually switches would be 1000v for 1000v IGBTs. (Or if you want to be precise, 1000v+Vce on)