View Single Post
Old 03-01-2010, 02:33 AM   #3033 (permalink)
squiggles
EcoModding Apprentice
 
Join Date: May 2009
Location: Australia
Posts: 109
Thanks: 0
Thanked 2 Times in 2 Posts
Quote:
Originally Posted by MPaulHolmes View Post

OK, now for the heat...

At 1000 amp, 100% duty, it would generate about 75 watts per mosfet (I guess a little more, due to switching losses). However, 100% duty and 1000amp would be very uncommon, since the 1000amp would usually only happen at very low rpm, which would mean very low duty.
My understanding was that the switching frequency and the switching time of the device affected the heat dissipation more than the duty. Theory being that it is the time spent in the linear region that is the big issue.
  Reply With Quote