72V 300A brushless controller

[Malcolm]

Looking for high-power brushless motors and controllers I came across this:
http://www.kellycontroller.com/mot/Brushless-DC-Motor-Controller.html
Out in December. It looks like a Chinese company but I've heard a few people mention them and someone I know in the UK has used one of their brushed regen controllers in a motorcycle conversion.
Their other prices seem good, so it'll be interesting to see where they set the price for the brushless controller.
Wonder if you can run the brushless Etek at 72V?

 

[TylerDurden]

Actually, the Etek will also run at 72 volts. It is neutrally timed, so it can be run in either direction, whereas the Perm is timed for clockwise operation.

http://endless-sphere.com/forums/viewtopic.php?t=2676&start=15

 

[Malcolm]

Patrick was talking about the brushed Etek. I seem to remember Fechter saying that Electric Motorsports had tried using the brushless version, but they couldn't get it above 200A with a Sevcon 48V controller.

 

[TylerDurden]

Patrick was talking about the brushed Etek. I seem to remember Fechter saying that Electric Motorsports had tried using the brushless version, but they couldn't get it above 200A with a Sevcon 48V controller.

Ok... I saw the reference to timing and the Perm, so i figured it was the brushless...

:?

 

[Doctorbass]

I wonder if it include some of the popular bulletproof mosfet like the 4110?

What's the price?

Doc

 

[maytag]

Last I spoke with Todd from EMS was at this years Annual Palo Alto EV event. He mentioned that theyve already tested the Brushless Etek at 60v with a brushless controller made out of China. Said it was very impressive at 60v, no word on 72v yet but that was a few months ago.

 

[Malcolm]

That's good to hear maytag. I'd really like to replace my brushed Etek with the brushless version if I can get near the same performance from it.

There's always a nagging worry that if a brushed motor controller fails it could give full power to the motor, but as far as I know a brushless controller will always be fail safe.

 

[fechter]

I think it was pretty sucky at 48v, but at 60 or 72v, It should rock.

The controller is the hang up right now.

Yes, having the controller short out and the motor go WFO on you can ruin your day. Even with a contactor to kill the power, it can throw you off so fast you won't know what hit you.

It should be possible to make a "shorted FET" detector that automatically kills the contactor. I've thought about it ,but it is a fairly tricky thing. I don't have a good design for one yet.

 

[xyster]

Yes, having the controller short out and the motor go WFO on you can ruin your day. Even with a contactor to kill the power, it can throw you off so fast you won't know what hit you.

Are there any combinations of component failures, or other faults, by which a brushless controller would suffer a similar, runaway fate?

 

[fechter]

Yes, it's happened to one of our members.

The throttle wires could short out and give a full throttle signal to the controller.

If you have the brake switches connected, you could stop it.

No combination of FET failures will result in a runaway motor.

 

[Anonymous]

What's the latest news on anti-runaway measures then?

Yes, it's happened to one of our members.

The throttle wires could short out and give a full throttle signal to the controller.

If you have the brake switches connected, you could stop it.

No combination of FET failures will result in a runaway motor.

 

[oatnet]

What's the latest news on anti-runaway measures then?

You gravedug a 3-year-stale thread about Kelly controllers to ask that question?

 

[fechter]

I'm not sure about Kelly, but many of the newer chinese controllers will shut down if the throttle signal goes higher than around 4.7v. Full throttle on most hall throttles is around 4v, so this protects against a shorted throttle line if using a hall throttle.

On one of my current mode throttle projects (for Alltrax controllers), I added a current sensing circuit that detects when the ground line is broken and inhibits the output. While this still won't protect against a 5v to signal line short, it does protect against a broken ground line which would result in runaway throttle.

 

[Anonymous]

Hi, yeah I dug it out, I only dug it out because I've got a brushed setup that could hurt if I don't learn to fix this problem, there's a pretty good reason to dig

What's the latest news on anti-runaway measures then?

You gravedug a 3-year-stale thread about Kelly controllers to ask that question?