Winding a more efficient motor

[Njguy]

Lets say that I'm building a DC motor. If I want to make it more efficient I could increase the number of windings. This actually doesn't make sense to me because if you want to double the amount of windings you need to use thinner wire so that you can fit them. So if you use wire that is twice as thin it also has twice the resistance. If you are doubling the loops you are also doubling the length of wire. So this seems to be 4x the resistance. If you have 4 times the resistance you need to double the original voltage. This works out to roughly the same power consumption, so what is the point?

Unless I'm totally miscalculating.

 

[Nigel Goodwin]

Increasing the number of windings doesn't increase efficiency, mostly it increases the voltage the motor requires to operate.

 

[Njguy]

Increasing the number of windings doesn't increase efficiency, mostly it increases the voltage the motor requires to operate.

Thanks. Since you are using less current would there be an increase in efficiency due to less heat being generated?

 

[Nigel Goodwin]

Thanks. Since you are using less current would there be an increase in efficiency due to less heat being generated?

Why would you imagine that? - do the simple maths - all you need are the two normal easy formulas V = I x R and W = V x I

Electric motors are VERY, VERY old and mature technology.

 

[crutschow]

Thanks. Since you are using less current would there be an increase in efficiency due to less heat being generated?

Not really, since the higher voltage motor uses more windings of thinner wire which has more resistance.

 

[ronv]

Give this a read - see if it helps.
https://www.micromo.com/motor-calculations

 

[mbarazeen]

The motor efficiency can be incresed by choosing correct lemination cores. for a given core to drive a certain load you cant do anything to improve. For motors if you increse the voltage current reduces to compansate electrical power taken to drive the constant load and vise versa ( if voltage drop occurs it takes more current and can lead to winding damage), simple application of V=IR will not work for motors. core losses (iron megnatizing loss & eddy current loss), loss in conductor, loss at bearing, air friction etc are kind of consideration for improvement