Turbine Generator

Fleming?
Del

"...rotating a (copper)wire loop in front of a permanent magnet will result in a change of the magnetic flux through the loop. This change in flux produce an emf and a current will start flowing in the loop. We have an electric generator. The basic function of a generator is to convert mechanical energy into electrical energy."

How do generators work....

If you are trying to compare the different types of field excitation on an electric Generator (Alternator), then you can google search for Permanent Magnet Excitation ... and select the topic that suits your level.

In a simple way: An normal field excitation uses electromagnets and rely on the remanent magnetism in the rotor iron to start the buildup of the full field/voltage.

A permanent magnet equiped system relies on the permanent magnet to start the ball rolling and to improve/garantee the filed will not collapse to zero in a massive short circuit case. This system will still need a variable field excitation using the electromagnet system. This gives the AVR the possibility to regulate the voltage output with the load variation.