# split-pi , can it work with igbt



## aeroscott (Jan 5, 2008)

split- pi as I understand it is a H-bridge voltage control . I could not open the patent link on it , so I'm in the dark . can it work with igbts instead of mosfets .


----------



## Tesseract (Sep 27, 2008)

Nope - it specific relies on the ability of MOSFETs to conduct current bidirectionally. This is without regard to the anti-parallel diode which is usually present, btw. Current can flow from drain to source or source to drain in a MOSFET when it is turned on. The gate still needs to be ~10V above the source, regardless of the direction of current flow, so an isolated or boostrapped drive circuit is required for all four MOSFETs in the split-pi bridge. 

Some caveats of this topology: the lower MOSFETs each have to be rated for the full peak current while the upper ones can be rated for half (they are always switched on and off togetether). The inductors and capacitor will be physically very large because they have to handle the full current as well. The capacitor needs to be very high quality film or oil construction. Frankly, while this circuit is clever, it's not particularly practical compared to a 2 quadrant drive with external reversing contactors.

Also, it's under patent


----------



## aeroscott (Jan 5, 2008)

thanks for the info , I'll check out the 2 quad .


----------

