some details about my scooter brushless motor?

[dutchlincoln]

Hello,
Ik became enthousiastic about the thread about switching a brushless motor from wye into delta.
Now, i have a scooter with a 48 volts 1500 watt moor, and want to increase the speed.
I already installed a Kelly KBL48201 controller, wich gave me much more torque.
Now, i want to know if i can put my motor into delta, and what i can expect from it.
The wires of the motor are 1mm thick, and is build by a strand of 10 wires (times 3 coils).
Is there a way to calculate the max. power in wye (presumably the 48 volts, 1500 watts), and what the power will be in delta?

Going with the 10x1mm wires, how much currect would i be able to push through it, before i fry the motor?

Thanks!

 

[parabellum]

Your speed will increase by factor of ~1.43
Motor/cooper resistance will be 1/3. (hard time for the controller)
Your power will always depend on controller output, probably it will be the same as before if same setting applied. Motor only sees the multiple of V*A until electrical speed limit is reached.

You can pump power in untill
1) cooper/insulation give up.
2) hall sensors give up.
3) magnets start to give up.

Solution: Cooling cooling cooling. It means- fatter wires, vent holes/oil bath cooling.

You can put your motor in Delta if it is in Why by now. Do you know how it is connected now?

Can you post some pictures?

 

[dutchlincoln]

hereby some pictures, if you need more, or specific details, let me know.
Thank you.

ps.
The diameter of the motor is smaller then an other scooter i have that is 1500 watts as well. It is almost twice as thick though.
It is from a E-Max scooter.

 

[parabellum]

Yes it looks Y connected. Is there potential to upgrade phase wires?

 

[dutchlincoln]

Yes, there is.
My current 1500W motor (i own 3 scooters) has much thicker wires as this one already...
I'm going to get a few meters of different gauges of wire tomorrow, and see what fits.
The cutback in the axle is wide enough to accomodate some big wires. (at least twice of whats in there right now.)

But, how much current would the motor be able to handle, with the given wire diameter given?

 

[dutchlincoln]

Your speed will increase by factor of ~1.43
Motor/cooper resistance will be 1/3. (hard time for the controller)
Your power will always depend on controller output, probably it will be the same as before if same setting applied. Motor only sees the multiple of V*A until electrical speed limit is reached.

So if i understand correct, you're saying that if the controller can cope with it, and deliver the needed amps, it will have the same torque as it has right now, and top speed will increase bij approx. a factor 1.43?

The thing i'm afraid of, is losing torqe..... I definately don't want a decrease in torque....

 

[parabellum]

Yes, there is.
My current 1500W motor (i own 3 scooters) has much thicker wires as this one already...
I'm going to get a few meters of different gauges of wire tomorrow, and see what fits.
The cutback in the axle is wide enough to accomodate some big wires. (at least twice of whats in there right now.)

But, how much current would the motor be able to handle, with the given wire diameter given?

You will never meet recommended specification for Ah for wire AWG, so your system will heat up and amount of power you can pump in continuously will fully depend on heat dissipation. Short bursts are also limited to heat dissipation. Use fattest wire possible for phases (to avoid converting them in to bottleneck, remember 1/3rd resistance of winding's at D, you should at best triple phase wire crossection) and try to create good thermal path from winding to ambient then monitor winding temperature (that's where most heat is created) and gradually raise power input.
Look for oil cooling hub treads and/or went hole cooling treads.

So if i understand correct, you're saying that if the controller can cope with it, and deliver the needed amps, it will have the same torque as it has right now, and top speed will increase bij approx. a factor 1.43?

The thing i'm afraid of, is losing torqe..... I definately don't want a decrease in torque....

What controller don't like is low inductance and resistance, but if it can swallow it then everything OK. Remember, motor does not see A nor V almost until the point it reaches its max freewheeling speed (edit: at given Voltage)! It only sees Watts. Your torque can get slightly lower only because of lower efficiency in low RPMs, but I do not think you will notice that in normal operation. BTW at climbing steep hill you will wish for a controller delivering more Amps to get in more efficient speed zone.
IMHO with few mods you can pump ~4KW continuous and 10KW bursts in it with no worry.

 

[dnmun]

someone will know, but i am certain you will lose torque if you go delta.

if you wanna save the torque and add top end speed then upgrade to 72V or something similar in lipo. jmho

 

[dutchlincoln]

ok, thanks guys.
I will look for the thicker wires, and steady upgrade the motor and put it in delta.
I will make equal connectors on it, so i can swap it easily with the current motor. This way, i will have a quite fair A:B comparising.
I'll let you know the results when i'm ready.

 

[dnmun]

i thought you said you needed to save the current torque? did i miss something? there are several threads on delta conversions so maybe you can read up on those to familiarize yourself with the performance changes to expect.

 

[dutchlincoln]

And if you read them as well, you can conclude that my specific question is not mentioned, nor explained...

Also, as I already did explain, i don't want to go higer in voltage....
see: http://www.endless-sphere.com/forums/viewtopic.php?f=10&t=37803

Talk about reading...

 

[parabellum]

ok, thanks guys.
I will look for the thicker wires, and steady upgrade the motor and put it in delta.
I will make equal connectors on it, so i can swap it easily with the current motor. This way, i will have a quite fair A:B comparising.
I'll let you know the results when i'm ready.

Just remembered about few comments about D to Y timing, 1 hall sensor position may not be perfect for both but if I remember well you will find combination that will work just OK. BTW I think it was described in DrBass's Y/D transmission/switch tread.

 

[dutchlincoln]

And if you read them as well, you can conclude that my specific question is not mentioned, nor explained...

Also, as I already did explain, i don't want to go higer in voltage....
see: http://www.endless-sphere.com/forums/viewtopic.php?f=10&t=37803

Talk about reading...

Dnmun,
Sorry, that was not nice to react this way, my apologies.
I was a bit upset yesterday, due some personal reasons.
I got a bit fed-up by everyone re-directing me to the thread, while i already had read it. Sorry.

 

[dnmun]

i guess i never read them that close. i had thought that the delta had less torque. did not realize you were stuck with 48V. i guess because you already bot a 48V controller.

 

[parabellum]

dutchlincoln, look at 5th picture in first post. Related to hall sensor timing.

http://endless-sphere.com/forums/viewtopic.php?f=30&t=38231

It is possible that you need other hall placement for perfect timing in D, (if you do not rewind the stator).