Stator creates ac voltage then the rectifier converts it to dc voltage to run all the lights and bells n whistles. Alts on cars same thing, mc's too. All electronic circuitry uses a small transformer to convert ac to dc volts. Every appliance in your house same thing. Computers, tvs etc...DC voltage is more efficient in electronics use. AC voltage is more efficient to transport over long distances to your home and to create. That's one reason alts replaced dc generators on old cars.