First. I know this is (probably) wrong, but I want to understand why, so please bear with me
The conventional wisdom is that the end turns on a stator are dead weight. A couple of the explanations for this I've seen go:
1) They are outside of the width of the magnets, so do not contribute torque, but have resistance, so still consume power.
2) As they run radially, their current does not cut the magnets fields in a way that contributes (Lorentz) force to the motor's torque, but have res...
3) Others...
But ... it is the field in the teeth that interacts with the magnets, and the windings create the field in the teeth; and if you think of a tooth as a squared off solenoid, each full turn, and all of the length of each turn, is used to calculate the field created by the solenoid.
By that reckoning, end turns contribute their proportion to the tooth's internal field, and are just as valuable and productive as those parts of their coils that run through the slots.
[strike]Discuss?[/strike] By all means, tell me I'm wrong; but please include why
The conventional wisdom is that the end turns on a stator are dead weight. A couple of the explanations for this I've seen go:
1) They are outside of the width of the magnets, so do not contribute torque, but have resistance, so still consume power.
2) As they run radially, their current does not cut the magnets fields in a way that contributes (Lorentz) force to the motor's torque, but have res...
3) Others...
But ... it is the field in the teeth that interacts with the magnets, and the windings create the field in the teeth; and if you think of a tooth as a squared off solenoid, each full turn, and all of the length of each turn, is used to calculate the field created by the solenoid.
By that reckoning, end turns contribute their proportion to the tooth's internal field, and are just as valuable and productive as those parts of their coils that run through the slots.
[strike]Discuss?[/strike] By all means, tell me I'm wrong; but please include why