Brushed motor solid magnet strength

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swagguy8
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hi guys! i was wondering if the solid magnet part of a brushed dc motor needs to be strong in order to make a strong motor? I'm designing a motor from scratch and wondering if i should use an existing ferrite magnet that is somewhat strong or should I design a electromagnet that is stronger.

thanks,
swagguy8
 
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A agree. You need to read up on DC motors.

It may seem obvious that a stronger magnet will give a stronger motor but it's not that simple. The strength of the magnet has an effect on the number of turns required to achieve the desired "no load rpm". Using a stronger magnet allows you to use fewer turns and so reduces losses in the winding resistance. In short a stronger magnet might produce a more efficient motor but (with some assumptions) both can produce a "strong" motor.

That said what do you mean by a "strong" motor? An ideal motor turns all the electrical power into mechanical power so they are all as "strong" as the power source. In the end it's real world effects that limit how much power a motor can deliver.
 
CWatters said:
A agree. You need to read up on DC motors.

It may seem obvious that a stronger magnet will give a stronger motor but it's not that simple. The strength of the magnet has an effect on the number of turns required to achieve the desired "no load rpm". Using a stronger magnet allows you to use fewer turns and so reduces losses in the winding resistance. In short a stronger magnet might produce a more efficient motor but (with some assumptions) both can produce a "strong" motor.

That said what do you mean by a "strong" motor? An ideal motor turns all the electrical power into mechanical power so they are all as "strong" as the power source. In the end it's real world effects that limit how much power a motor can deliver.

what I mean by strong is lots of horsepower, preferably high rpm

thanks for the replies everyone especially for that link, ultrafastped
 
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