What Does an Alternator Do?

An alternator is a device that generates alternating current (AC) electrical power in a vehicle. It converts mechanical energy into electrical energy by using a pulley and belt system to spin a rotor inside a set of stationary electromagnets. The rotational motion of the rotor generates AC voltage, which is then converted into direct current (DC) voltage by the alternator’s rectifier. The DC voltage is used to charge the vehicle’s battery and power the electrical systems of the vehicle. The alternator is typically driven by the engine of the vehicle, so it is able to produce electricity as long as the engine is running.