How does a Mecc Alte Alternator control it's voltage?

[merryengineer]

Hi,

Can you please tell me how a a Mecc Alte alternator controls its voltage?

[wellandpower]

It depends on the machine. Assuming the machine has an Automatic Voltage Regulator fitted:

The AVR monitors the voltage of one or more phases. If the voltage is not at the correct level, it changes the voltage of its AC feed to the excitor stator, which then uses its diodes to rectify this to DC. This DC current is passed through the rotor, which in turn regulates the voltage in the main stator.