3000W with >90% efficiency?

General Discussion about electric bicycles.
Post Reply
sven_nilsson   10 mW

10 mW
Posts: 25
Joined: May 10 2014 11:28am

3000W with >90% efficiency?

Post by sven_nilsson » Jun 18 2014 5:29pm

I just found this:

http://www.uumotor.com/wp-content/uploa ... V3000W.pdf

It looks interesting, and there is nothing obviously bogus about the results. However, the high efficiency occurs at very high (~1000) RPM, which makes it not very useful unless you have smaller rims.

Comments? Does anyone have experience with this motor? I'm looking for a more lightweight and less powerful (~1000W) motor with a similar high efficiency, but they seem very hard to find.

User avatar
Allex   1 GW

1 GW
Posts: 3203
Joined: Dec 05 2011 8:46am
Location: Stockholm, Sweden

Re: 3000W with >90% efficiency?

Post by Allex » Sep 09 2014 4:32pm

Just a Cromotor clone. similar to quan shun 3000W. It is a good motor

User avatar
dogman dan   100 GW

100 GW
Posts: 34985
Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: 3000W with >90% efficiency?

Post by dogman dan » Sep 10 2014 7:29am

Sure, at no load full speed, efficiency is great. ( if the winding isn't saturated) It's producing close to no torque at that point.

I might get dope slapped for this, but my impression is that a wider magnet stalls less at slow speeds, so my big motor seems much more efficient under heavy load, at half no load speed. Hard to prove this, but the big motor climbs a hill faster at 1500w than a small one. The difference is not huge though, since 1500w only does but so much when climbing a steep hill.

Similarly, a gear motor running at 1000w seems to climb a hill much faster than a dd with the same power. The gear motor stalls at a much slower speed due to the reduction gearing.

Post Reply