Not sure exactly but there is a bit of speculation going on
From that site:
"The use of 11 (apparently) separate inverters (6 x 11 = 66 IGBT's @ 600V ) makes each converter easier to design and to cool. The peak current in each IGBT is about 60A (figured as each inverter peak power is 200kw/11 = 18kw = 300V (with sag ) x 60A). So the inverter are likely conventional using 100A (or 159A) 600V IGBT's."
I know there are actually 72 IGBTs in a tesla, probably 66 for 11 inverters plus 6 more for a brake chopper? hard to say but they've got some crazy stuff happening in that car