Some of these drone motors look fantastic for the application but they mostly seem to be made by Chinese companies that don't provide dynos or efficiency specs at all ( gotta pull it out of them, each and every one )
That is a nice halfway point and it's cool to see this experiment executed!
Over the past few weeks, I’ve been searching for an efficient BLDC motor to build a single or dual-geared transmission. However, after some research, I realized that finding the right motor is quite challenging. Many of the BLDC motors I came across were only about 80% efficient, or their efficiency wasn’t specified on the websites selling them. Additionally, some motors couldn’t deliver the required torque for our needs.
I reached out to Astro regarding their 95%-efficient motors, but I haven’t received much of a response yet. In the meantime, I came across a site called Tmotor, where I found some promising options. I’ll include links to those below. While these motors seem decent, they don’t appear to offer significant efficiency gains over a hub motor with 85% efficiency.
Does anyone have experience with Magic Pie hub motors? Could they be a good option for our car?
Have anyone found or used any BLDC motors with high efficiency? I’d appreciate your suggestions and insights.
If you poke around with the search engine, you'll see quite a number of posts and threads discussing various versions of the GoldenMotor Magic Pie that might be helpful for you to make decisions, including some where they were customized in various ways.
There are also various threads about efficiencies of different types of systems in various usages. Keep in mind that a motor's efficiency is directly affected by how it is used vs how it was designed to be used. The simulator at ebikes.ca may help you see how that works if you're not already aware.
Golden pie isn't a particularly efficient motor ( <= 85% peak ) , but it can produce a lot of torque from a stall without losing efficiency due to the huge diameter.
There do exist a number of 2nd candidate super efficient RC motors that are worth checking out if the astro guys are unresponsive.
For example maytech makes RC motors with 0.2mm laminations and nice windings. They don't publish efficiency specs but razor thin laminations and nice windings may indicate peak efficiency in the 90% range, which is pretty good. Maytech Brushless 6374 90/170/200KV/330 Sensorless Outrunner Motor for
of course you're gonna need double reductions to take advantage.
from post #24 in this thread Custom axial flux permanent magnet BLDC | Ultra light electric motor
Company claims 90% efficiency across the range of sizes.
140mm diameter should be enough.
Lowish RPM so a single stage reduction should be all that's needed.
Axial flux design is generally good for torque.
Consult the company on size and controller needs.
Ask if they can provide a school educational discount.
