Quote:
Originally Posted by MazdaMatt
Thanks for that explaination. I knew how they operated, but did not know that the transient would generate so much heat. So the frequency of switching is a trade off between efficiency (heat generated on the board) and smoothness/sound. ie, you COULD switch it at 1Hz and generate practically no heat, but shake your car to death, 1kHz and hear an annoying buzz with very little heat, or 4kHz like you and generate some heat that can be dissapated and there's some vibration/dog whistle or 1Mhz with huge heat loss and perfect smoothness....
I guess you'll have to do some tuning  |
Ya, I'm thinking of maybe just biting the bullet and running it at 16 kHz like everyone else. I don't know. I found out that lower switching frequencies causes heating of the capacitors (more voltage ripple). However, I'll be using quite a few of them, but still, maybe it would be best to raise the frequency a bit. It's easy to do. Like 1 like of code or something. It will change the number of possible throttle positions to 512 if I run it at 8 kHz, and 256 possible positions if it's run at 16 kHz. I think 256 different settings would be plenty smooth.