How the Alternator works

The charging system of a vehicle is made up of three components; the battery, the voltage regulator and the alternator. The alternator, getting its name from alternating current (AC), works with the battery to power up the electrical elements of the vehicle. All vehicles with an internal combustion engine have an alternator.


How it works

Cars run on rechargeable batteries. The battery is recharged by the alternator. The alternator can be considered a type of generator. It is driven by a belt from the engine. The stator is the part of the alternator composed of an immobile set of wire coil windings.


The rotor revolves within the stator. This element within the alternator is an electromagnet. Electricity is created by two metal slip rings contacting copper or copper-carbon brushes and is supplied to the rotor. As the electromagnet rotates within the stator, it creates more electricity.


The alternator is basically a loop of wire with a magnet in the middle. As the north pole of the magnet passes the top of the loop and the south pole passes the bottom, the current flows in one direction. When the poles move away, the current stops flowing. The current continues flowing, but in the opposite direction, when the poles reach their designated points again.

Back to basics

There’s a lot of science involved in how the alternator works. The basic explanation is that the alternator is one of the components of a cars charging system. It creates electricity in order to keep your car battery charged and to keep all the electrical elements in your car working.


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