Electricity Generation

Fundamentals and basics of electricity generation were discovered by the British scientist Faraday since the year 1820.

Electricity practically generated at power station by electromechanical generator which convert the kinetic energy to electrical energy, this kinetic energy may resulted from some type of sources like, heat engines fueled by chemical combustion or nuclear reactions or water flow or wind flow …etc. Also in some types of power station electrical energy may be generated from solar energy (photo voltaic) or geothermal power.

After the electricity is generated, Electric Utilities precede in the two second steps to deliver the electricity to the consumer which called Transmission and distribution.

The question is…… How the electricity is generated in the electromechanical generator?

According to Faraday Law, when a loop of wire or a disk of copper move between the poles of a magnet, electrical current will generated in this loop or copper disk.

This is the basic idea of how generator create electricity, as the generator contain  wire wingdings called armature which is stationary and a magnetic field rotates around this armature so  electrical current and voltage gets generated in the armature winding which is connected directly to the load.

The magnetic field is generated practically from the exciter which consider as apart of generator. This exciter supply direct current to the generator field winding to magnetizing the rotating poles and sets up a steady magnetic field.  The exciter is controlled by a voltage regulator; there are two types of exciters:

1-Bruch type with a movable commutator.

2-Static excitation or also called brushless exciter.

The resulted current and voltage waveforms at the generator terminals are proportional to the strength of the magnetic field and the frequency (HZ) of the resulted voltage waveform depends on the speed of rotation and the number of poles.

Hint: Frequency means the number of complete cycles of the generated voltage per second and it measures in HZ.

At the end we should know that when the current flow throw the generator armature ,it faces the resistance and inductive reactance of the armature windings which called the internal resistance and after that the current will flow to feed our loads ,Consequently lamps will light , motor will rotate, factories will work and commercial building will be illuminated  …….. Indeed we cannot live without electricity, it consider the artery of the life.

What is Electricity?

To answer this question we should know about the atom. Every thing in our life consists of variable number of atoms. Atom considers the smallest part of any thing and it made up of three components :-

1- Protons: a positive charges present in the middle of the atom, called the nucleus and they are stationary.

2-Neutrons: have no charge, they are a part of the nucleus of an atom with the protons.

3-Electrons: have negative charge, they are very small and are not apart of the nucleus of the atom, but they move around it in orbits. They are the only part of an atom that can move.

The number of negative electrons in the atom is generally equal to the number of positive protons so the atom is in balance in normal conditions until an external force affects the atom at this case the atom may gain or loss electrons.

Electricity is the flow of the movable electrons as when these electrons move from one point to another point, this called electrical current.

Nowadays we cannot live without electricity, without it we cannot watch TV or listen to radio or heat the water, every thing in our life depend on electricity .