Brushless motors!

Hey guys,

I've got an electric scooter here I'm planning on modding. It currently uses 2x12V7Ah SLA's and a 200W brushmotor. I was thinking of replacing it with a couple 6S 5Ah LiPo packs, a proper e-bike controller (With regen braking) and a ~2kW brushless motor.

Problem is, the brushless motors are really designed to be used for things like propellers, where they'd be exposed to a hell of a lot of airflow. In a scooter, it' kind of tucked away between the wheel and battery compartment, so wouldn't get much airflow at all.

So I'm wondering, does any one have any experience with how much cooling motors (Such as this one I'm looking at) will need?Turnigy Aerodrive SK3 - 6374-168kv Brushless Outrunner Motor


i'm thinking I may be able to mount a blower fan on the back of it or something to help with airflow, but space is kind of an issue:



Of course, the motor wont be running at full power, except maybe very rare exceptions for a short time. A more typical value would probably be around 33%.

I'll do up a separate thread on the project if anyone is interested in following along

Dan

I use a 5364 270KV motor and 4000mAH 6S Li-Po in an
8 foot wingspan L-4 cub.

The motor comes quite hot when the throttle is held open
for most of the flight.
There is only minimal cooling from the 21" prop since the
motor is only 53mm (2-1/8") in diameter and the prop hub
is ~3-14" in diameter.

The other problem is the 6S Li-Pos become hot as well.
In your scooter I would think it may require some fan
cooling since you won't hit any high speeds for forced
cooling...


Jerry

You can contact us at any time on our Website: J.BAUER Electronics

Interesting, thanks for the info.

I'm hoping that by seriously overrating the motor and batteries I'll be able to avoid serious heating issues. Like I said, there is no way I could run the motor at full power, because the acceleration would be enough to throw you off the thing before you even realize you're touching the throttle. I think I calculated it at 6.3m/s/s acceleration full throttle with a 100kg rider. Of course not taking friction, air resistance, road surface etc into account, but it's still pretty serious.

I was considering maybe attaching a fan blade to the back of the motor (seeing as it's an outrunner), but I dunno if the speed it'll be going will be adequate to cool the motor. Cooling the ESC shouldn't be too much of an issue. Batteries shouldn't be too bad I hope. Of course I'll have a uC with temp sensors scattered all over the place for monitoring temps