Turns verses Winds
"Turns" of wire define the speed. More "turns" means a lower no load speed and more torque at lower rpms.
"Winds" are the number of interconnects that exist within the "Turns".
A
"Single" wound motor has the most low end torque and also the highest inductance and highest resistance. This winding pattern is best for people who want the most torque at the lowest rpm, but is not very good for efficiency.
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"Double" wound motor has less low end torque, one fourth the inductance and one fourth the resistance. This will create a more linear motor torque and has more power in the top end. This is a higher efficiency motor because it has less resistance.
The
"Triple" and
"Quad" wound motors tend to have very little torque down low, but tons of power up top. It's often hard to be able to deliver enough amps to actually get this type of motor to fully function at it's peak.
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One can choose a thin wire and high "Turns" and then just "Double" or "Triple" or "Quad" wind it if you are willing to sacrifice low end torque.
I know about this because I'm working on it right now... the Unite 1200 watt motor was a "Double" while the Unite 750 watt was a "Single". The "Double" worked better for my needs because I use gears. (I don't need low end torque)
http://www.rccartips.com/advanced-rc...motor-tips.htm
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The reason that the lower resistance motors tend to be more efficient is that they work best at their higher rpms. People who want low rpm torque often go with a "Single" wound motor and that means that the resistance will be higher than you could get with the "Double". At the low rpms the motor inductance acts like a "flywheel" and allows a smaller current to maintain itself while the PWM controller is sending pulses to the motor. It's the inductance that creates that "EV Grin" down low. The best power is actually up high... well past the "EV Grin" point.
This is something I have spent a lot of time playing with too... using Armature Current Limiting you can get excellent top end without needing to overheat your motor. However, this is another case where multispeed gearing is a necessity or you might bog down in the low rpms. It's just like with gasoline motors... the race cars / race motorcycles tend to get their best power up high in the rpms. Something like a tractor with a large flywheel is designed for low end torque.
You end up picking the motor for your needs...
But the best efficiency and power is going to have a lower resistance... that's a "fuzzy rule" that does work pretty well to classify things.
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