Hello! I have a quick question about PN diodes in a simple buck converter application for a single quadrant series DC motor drive (expecting load currents in excess of 600A, especially during acceleration). Rather than interleaving two Trench-Stop IGBT buck modules, I am wondering if simply placing two identical buck modules in parallel would be ok, since I want to avoid the isolation inductors (and more sophisticated controls) required with interleaving.
Free-wheeling diode question
The free-wheeling diodes in the module (APTGT600SK60G) are soft-recovery PN junction diodes. Since they are minority carrier devices, a little voice is telling me that they might not share current equally, and this could potentially be a problem (not 100% sure). But I would think that the IGBTs might force the free-wheeling diodes to share current equally since the IGBTs should share current. Also, if the modules are “identical” then this might help with current sharing too. Again, not sure. The modules will be mounted on laminated bus bar. So the question is: is it ever ok to simply parallel buck modules if the FWDs are PN junction diodes? Thanks for all the comments and advice.