Before we talk about how a generator works, you should know what a generator is and what are good generators and bad ones.
What is a Generator?
Scientifically speaking, a generator is a device or a machine, which converts mechanical energy into electrical energy so that it can be used in an external electrical circuit. -Basically, a generator is a machine, which works on fuel to convert mechanical energy that is, kinetic energy and potential energy into electrical energy so that you can use electrical appliances.
What is a Good Generator?
A good generator is that generator in which only a small amount is lost due to friction most of the mechanical energy is converted into electrical energy. Putting it simply, it means that a good one is that which is efficient and provides good output for input that is put into the generator and does not lose a whole lot of energy in the form heat.
What is a Bad Generator?
Now, I am guessing that you already know what a bad generator is from its name, but for those dummies who still do not get it, the bad generator is that generator which is not efficient and loses a lot of energy in the form of heat (friction).
How Does a Generator Work?
Principle: Generator works on the principle of Faraday’s law of electromagnetic induction, which says that “whenever, the magnetic flux which is linked with a closed circuit changes, an e.m.f. (electromotive force) is induced in the circuit” which in normal words, means that, whenever a conductor is moved or if it is kept in a varying magnetic field, an electromotive force is induced in the conductor.
(Note: Magnetic flux is the amount or a total number of magnetic lines of force that are passing through the surface of the conductor.)
Working Mechanism Generally, in most of the generators, a rotor spins within a conductor to produce the same effect as mentioned in the principle of Faraday’s law of electromagnetic induction and induce a current. In most cases, an electromagnet is used as the rotor instead of an actual magnet. An electromagnet is a conductor which acts as a temporary magnet which produces its magnetic field using the electric current. The electromagnet forms a magnetic field around it. When it is rotated, it affects the magnetic field as well. Because of the rotation of the magnet, the magnetic field also varies. Because the electromagnet is being rotated within the conductor, the conductor also lies within the varying magnetic field of the rotating electromagnet, due to which, as mention in the principle above, an electromotive force gets induced in the conductor.
And, that’s basically the base of how a generator works but there are many other things that have an impact.
For Kiddies: Take two magnets and place them a few inches apart. Now, go to your kitchen and bring an all metal spoon. Move the spoon back and forth between the two magnets.
What did you just do? You just induced an e.m.f. in the spoon. That’s what happens in the generators as well but at a way larger scale. What you actually did was, you moved a conductor (the spoon) back and forth in a magnetic field (because you moved the spoon in the area between the two magnets), and therefore, according to Faraday’s law of electromagnetic induction, you induced an electromotive force.
That’s basically how a generator works. If you want to learn more, you should start paying more attention in Physics classes! 😛 (If you are a student)