How does: more coils, curved poles, electromagnets: effect the effectiveness of a.c generators?
-
This question is far too big to answer in a few words.
All that I can say is that "effectiveness" might mean efficiency, or it might mean small size, light weight, high output.
A different answer would apply to each one.
But for efficiency, energy put in must either generate electricity, or be lost in the form of heat.
Any way to reduce the lost energy improves efficiency. Large diameter wire reduces resistance.
However it adds to weight and cost.
Multiple poles normally do not add to efficiency but they reduce the necessary rotational speed. Necessary for large generators.
Permanent magnets are more efficient than electromagnets but they give no control over the output emf so they are very rarely practical.
In most cases the alternator is a compromise between all the factors.
All that I can say is that "effectiveness" might mean efficiency, or it might mean small size, light weight, high output.
A different answer would apply to each one.
But for efficiency, energy put in must either generate electricity, or be lost in the form of heat.
Any way to reduce the lost energy improves efficiency. Large diameter wire reduces resistance.
However it adds to weight and cost.
Multiple poles normally do not add to efficiency but they reduce the necessary rotational speed. Necessary for large generators.
Permanent magnets are more efficient than electromagnets but they give no control over the output emf so they are very rarely practical.
In most cases the alternator is a compromise between all the factors.