okay, i spent a bit of time rigging up a rather crude test.
here's what i did.
1. ambient temperature is 20C (its regulataed in our building)
2. setup track simulation with 50% throttle (50% brake) and 100% throttle (100% brake). total run time was 5 minutes each.
speed control was a keyence zero (it has onboard fet monitoring).
and load was a centrifugal clutch device that squares the load as speed increases (similar to a proper car). Motor was Integy Matrix 12 triple
anyway run 1 with 100% throttle, temperature was 44C after running.
let both motor and speedo cool and repeated it with 50% throttle and temperature got to 54C.
let it cool
Repeated 100% throttle got, 46C
let it cool again
repeated 50% throttle got, 54C
based on that it is clear that running partial throttle heats the fets up more.
its a fairly basic test but since the only thing i changed was the throttle position i think it is conclusive.
sanj