How Alternator Works in your Car? - Valuable Guide

If you think your responsibility is over after buying a good battery for your car, then you are wrong. Yeah, your car battery is indeed responsible for starting your car engine and other accessories of your car. But did you ever wonder what charges that battery? Your charge your smartphone battery every day so that it can run the whole day without ant hassle. The same thing happens with your car battery. And your car alternator is that important part which juices up the battery. So, how alternator works in order to provide such power into the battery regularly? How does the alternator charge the battery? How does a car's alternator work? What are the symptoms of a bad alternator?

We did deep research on that, and now we are going to deliver it.

What is an Alternator?

At first, we need to discuss what is an alternator. We all know that the amount of energy in this universe is fixed. It only changes its form from one to another. This rule is known as the conversion of energy. An alternator is the perfect example of this. It produces mechanical energy and transforms it into electrical energy. This is the shortest and quickest overview you can get. But if you are looking into deep then welcome to the next few passages where I tell you what’s the working principle of your car alternator and how it creates a difference in your car’s performance.

Main Components of an Alternator

There are some components inside the alternator which creates and converts the mechanical energy into electrical energy. These are the key components of an alternator.

1. The Regulator:

The voltage regulator helps to charge the battery of your vehicle by distributing power. It controls the power distribution with the regulator to ensure the battery is getting enough juices continuously.

2. The Rectifier:

The current produced by the alternator is AC. But the battery requires DC supply to charge it. So, there is a rectifier circuit to convert AC into DC.

3. The Rotor:

This is the main moving part of the alternator. It can rotate with the help of a pulley and drive-belt system. The rotor works at a spinning electromagnet here.

4. The Slip Ring:

Slip ring helps the rotor by proving direct current and necessary power in it.

5. The Bearing:

A bearing supports the rotation in the rotation shaft.

6. The Stator:

It is some wire wound coils which go through an iron ring. It sits outside of the rotor. When the rotor rotates, it creates a magnetic field. Then an electrical current produces inside the stator.

7. Pulley:

The pulley is responsible for the rotation of the rotor. It is connected with the rotor shaft and drive belt system.

How Alternator Works

The working mechanism of the best alternator might look very easy from the outside, but in the inside, a lot of things happen. That is why you should know how does an alternator work? I have split those mechanisms into some highlighted events. I will discuss broadly there. There are basically four common steps that happen inside an alternator.

1. The rotor rotates with the help of the pulley attached to it.

2. The electricity produces inside the stator by following the law of electromagnetism.

3. The alternating current converts into direct current in the rectifier circuit.

4. The voltage regulator gives the signal to start or stop the rotation of the rotor.

The Rotation of the Rotor

So, first of all, we need to rotate the rotor. We all know that the alternator uses the principle of electromagnetism to produce the current. If you don’t know what the basic principle of electromagnetism is, then let me just clear it for you. If you continuously move a magnet across a coil of wire, then a small amount of voltage produces. But you need to keep the movement continuous otherwise the voltage will disappear. If you multiply the turns of that coil with a bigger number, then you will get a more output voltage. In a car alternator, the rotor is connected with the alternator pulley. The drive belt spins the pulley, and as a result, the rotor starts to rotate.

The Creation of Electricity Inside the Stator

The rotor is equipped with some electromagnets and can move freely inside the alternator. We use electromagnets here so that we can regulate the output voltage generated by the alternator. All magnets have two poles, and electromagnets aren't an exception here. The electromagnets are arranged in such way so that the north poles and the south poles are evenly distributed. When the rotor rotates, the current is applied through the brushes in the rotor to magnetize it.

On the other hand, the stator which remains stationary at the body of the alternator has three sets of wires with a huge number of loops. The rotor creates constantly reversing voltages in those three wires that mean it creates the alternating current (AC) in the Stator.

Converting AC to DC

The main task for your alternator is to charge up the battery. But your battery will only take DC to charge itself up. So, the only way to charge this thing is by converting the alternating current produced inside the stator into DC. To do that, we use a series of 6 diodes in a rectifier circuit. A diode is an electronic component that only allows current to flow in a single direction. Every two diodes are connected reversely for one of these three sets of wire. With this rectifier circuit, the alternating current converts into direct current and now your battery is ready to charge up.

The Voltage Regulator

The voltage regulator plays the most important role in charging your battery. It is placed inside or outside of the alternator. Most of the time, you will see it inside expect from some Ford cars. In those cars, a wiring harness connects it with the alternator.

The main task for the regulator is controlling the field current applied to the rotor inside the alternator. If there is no field current is applied, alternator cannot produce voltage. If the voltage drops below 13.5V, the regulator will start applying field current. As a result, the alternator will be charged. When the produced voltage exceeds 14.5V the voltage regulator will automatically stop applying field current and alternator charging. Thus, a voltage regulator helps to keep the alternator voltage between 13.5V to 14.5V, which is ideal for your car battery.

Signs That Tell Your Alternator is Bad

You should notice some symptoms if your alternator is bad or dead. Most of the time, we misjudge those symptoms and blame the battery. Let's take a look at what are those symptoms.

1. Headlight Flickering:

Imagine you are driving at night and your headlights are flickering or dimming. That might happen because your alternator is in bad shape. This horrible experience can be dangerous in highways. So, you better check the alternator first to get rid of this situation.

2. Weak Battery:

If you feel the battery is weak or dead, there might be two cases. One, the battery is actually dead and the second one is your alternator has gone bad or alternator overcharging issues occur. To determine which one is having the issue, you should check your battery when the engine is turned off. Check for the voltage in your battery. If the reading is standard, then the problem should be occurring from the alternator.

3. Noise:

If unusual noises coming from your alternator or alternator becomes overheated, then there's something wrong for sure. Your alternator has a rotor inside it an in continuously rotates without creating any sound. But if any unwanted noise is now coming from it, then you know what to do. Check it when you are in a silent garage. Run the engine to determine the noise.

4. Difficulty When Starting the Car:

Having troubles with starting the car? Is it not starting or starting after several attempts? Well, don't blame your car battery. It might be the alternator who can produce enough juices for your car. Check for the output voltage to determine the issue.

5. Electrical Failures:

The only source of the electrical power of your car is the alternator. If this goes bad, then your car's electrical functionality can hamper and might become a failure. Voltages might go up and down and sometimes your car accessories like AC, Radio, Lights etc. will not work.  If you face this type of issues, then you need to call a mechanic as soon as possible or change your car alternator.

Conclusion