View Single Post
Old 11-23-2015, 09:50 AM   #2349 (permalink)
Master EcoModder
P-hack's Avatar
Join Date: Oct 2012
Location: USA
Posts: 1,408

awesomer - '04 Toyota prius
Thanks: 102
Thanked 252 Times in 204 Posts
I appreciate the wye confirmation, but otherwise it isn't making a lot of sense to me.

The 300kw model S weighs about 5000 lbs, 3000 lbs is arbitrary, right?

millions upon millions of of motors have been switched between wye/delta, because it is a lot simpler than a rewind, you might want to check with a motor shop if you are not going to put in more batteries to get to 650v. It is an incredibly useful thing for others.

But in the mystery that is toyota, the biggest question is the 4x75kw assertion. that exceeds your pack hp capabilities, and it is a question of the coercive strength of the permanent magnets, push them too hard and they get destroyed, regardless of how much cooling you have in the stator. Do you think toyota didn't consider that in their 50wk rating? Or when they limited battery boost power to ~30kw? Nobody is using 300kw of boost converters in an EV, and the battery cooling plan sounds sketchy at best.

Also I never said single speed gearboxes are the main problem, but choosing the best ratio is certainly is a major consideration. I assume you are stuck with the mgr ratio, which is fine, and all the more reason to give delta a serious try, since you might not be able to throw more amps at the motor without destroying the magnets, but you might be able to push the breakdown rpm a lot higher than stock if you do wind up with more batteries AND delta.

Last edited by P-hack; 11-23-2015 at 09:57 AM..
  Reply With Quote