Introduction to Electricity

• Basic concepts of electricity
• Presented by ING. Anthony Pérez Meza, MS.C, SAP Consultant | Teacher

Introduction to electricity

• Electricity involves physical phenomena related to the presence and flow of electrical charges.
• Electricity manifests in various forms, including lightning, static electricity, electromagnetic induction, and electric current flow.

Electron Behavior and Materials

• Electrification involves the loss or gain of electrons.
• Electrons need mobility for electrification to occur.
• Metals allow the movement of electrical charges, and are called electrical conductors.
• Materials like glass, plastic and silk prevent the movement of electrical charges through them, and are called electrical insulators.

Theory of Electromagnetism

• Magnetism and electricity are closely related; magnetism, both natural and artificial, allows for electricity generation economically
• James Clerk Maxwell, a Scottish mathematician, first explained the relationship between electricity and magnetism in 1870.
• Electromagnetism is the magnetism produced by electricity and has applications in industry
• Applications include electrical generators, dynamos or alternators, transformers, relays, and motors.

Electromagnetism Basics

• When a coil of wire is wound around a support and an electric current passes through, it creates a magnetic field.
• The magnetic field's intensity increases with the number of coil turns and the current's intensity.

Electromagnetism Applications

• Alternators, dynamos work through the principle of induced current in a winding when a magnetic field changes.

Transformers

• Transformers are based on self-induction and mutual induction.
• They consist of primary and secondary coils wound around a ferromagnetic core
• Input of 120 V generates magnetic field, inducing a current

Transformer Functionality

• Induced voltage in the secondary transformer depends on the turns ratio between primary and secondary coils, and primary current.
• Self-induction limits the charging time of a coil, especially in high-frequency ignition transformers

Electron in Matter

• Electricity starts with the movement of a tiny particle called an electron.
• The atom, the smallest part of matter has a nucleus with protons (positive charge) and neutrons (no charge).

Atomic Electron Dynamics

• An atom can have many electrons orbiting the nucleus.
• Electrons can be removed from outer orbits, leaving the atom with a positive charge (ion).
• When an electron leaves its orbit, it creates a "hole", attracting an electron from a neighboring atom.
• This initiates a chain reaction of electrons moving between atoms, creating electrical circulation.

Electrical Force and Equilibrium

• The force that drives electrons in a conductor depends on the electron difference at each end
• Many electrons one end and few on the other cause a natural electron flow toward empty spaces, reaching equilibrium.

Subatomic Particles

• Electrons have small mass and carry electric charge
• Protons are heavier than electrons and carry electrical charge
• Neutrons have no electrical charge; their mass is same as protons.

Atomic Structure

• Atom consist of a core and a cortex.
• Nucleus includes protons and neutrons, amounts vary by element.
• Hydrogen has one proton; Sodium has eleven protons, twelve neutrons.
• Cortex contains various layers where electrons orbit the nucleus.

Electrical Machines

• Electrical machines are mechanisms that generate, use, or transform electrical energy.
• Generator: Converts mechanical energy into electrical energy.
• Motor: Changes electrical energy into mechanical energy.

Conductors and Magnetic Fields

• A current-carrying conductor within a magnetic field moves perpendicularly to the field; direction depends on current flow.
• A current-carrying loop will have one side move up and the other down within a magnetic field, creating rotation.

Electric Motors

• Motors are rotating electrical machines.
• Motors transform electrical energy into mechanical energy.
• Benefits includes economic factors, less pollution, user-friendly, safety.
• Electric motor’s reliability has allowed to take the place of many different energy forms across industry and homes.

Motor Function

• Motors rely on attraction and repulsion between a magnet and current-carrying coil.
• Essential parts include coil, magnet, and power source.
• Modern electric motors utilize multiple coils called windings in the rotor , plus a large magnet the stator.
• Some motors have their windings in the stator and magnet as the rotor.

Dynamos and Alternators: Principles

• Michael Faraday discovered that moving an electrical conductor within a magnetic field generates voltage.
• When the circuit closes with a receiver, electric current circulates.

Dynamo

• To extract current, collectors are attached to the ends of the loop.
• The collectors move against fixed brushes where the electricity exits the device
• The collectors are partially cut.

Alternator

• Use same coil to change polarity on each turn
• Same process for dynamo, but collectors are not cut

Electricity Production

• With a knowledge of the principles to generate electricity, electricity can be extracted from different sources such as biogas, geothermal, wind, thermal, or hydro.

Electric Current

• Electric current consist of two types: alternating current and direct current.

Direct Current

• Direct Current (DC) is the name for current that moves in one direction.
• Dry cell batteries are an example of DC power

Alternating Current

• Alternating Current (AC) is described as charges flowing in one direction and then flowing in the opposite direction.
• AC changes cyclically throughout the circuit
• Cycles per second is measured in Hertz (Hz)

Voltage & Potential Difference

• Potential difference (or tension) is to give a positive force the energy to move from one point to the other
• Measurement is in Volts (V)
• Just as pressured is need water to circulate a pipe, power force is need for current to circulate a conductor
• Voltmeter will measure this difference
• It is always connected parallel in circuit to measure the difference of power

Current Intensity

• Current of Intensity is the amount of electrical charge flows for a conductor for unit of time
• It measurement is Ampere (A) of coulomb for time
• Ammeter measures intensity
• Ammeter is always connected in series circuit

Electricity Production from Fossil Fuels

• Electricity generation from fossil fuels is known as thermal power.
• Thermal power utilizes gas, coal, bunker fuel, nuclear energy, wood, and all follow same concept.

Thermal Power Plant Operation

• A generator is connected to a transformer, increasing voltages for transmission.
• High tension transmission lines sends nominal voltages of 25 to 132 kilovolts, voltage depending on designer and electrical company
• Increasing transport voltages is important with wires travelling long distances that produces main voltage output that gradually decreases

General Principles

• Any production of fuel is highly contamination and costly due to CO2 emission in air.
• World energy demand maintained at 14%, due to population growth and development that demands energy
• Essential energy primary includes fossil fuels, nuclear fission, and renewables.

Hydraulic Energy

• Hydropower utilizes reservoir, dam or connecting shaft, intake river, forced pipe, turbines before discharging.

Wind Energy

• Wind utilizes wind direction, brake rotor, anemometer, and controller by shaft of high speeds.

Photovoltaic

• Solar or photovoltaic is generated on rooftops, solar generators that measure to data

Geothermal and Biomass.

• Electricity created through harnessing heat of earth and biomass respectively

Tidal Power

• Electricity created through sea or tidal movements