The discussion revolves around the strength of the solid magnet in a brushed DC motor and its impact on motor performance. Participants explore whether a stronger magnet is necessary for creating a powerful motor, considering design choices between existing ferrite magnets and electromagnets.
Participants express differing views on the relationship between magnet strength and motor performance, indicating that the discussion remains unresolved with multiple competing perspectives.
Participants mention real-world effects that limit motor power delivery, but the specifics of these limitations are not fully explored or agreed upon.
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.