Introduction to Electrical Systems PDF

Introduction to Electrical Systems LECTURE MODULE #01 ABUTLI2S  Definition – Electricity is the flow of electrical power or charge. Using electricity, we can transfer energy in ways that allow us to do simple chores....

Introduction to Electrical Systems LECTURE MODULE #01 ABUTLI2S  Definition – Electricity is the flow of electrical power or charge. Using electricity, we can transfer energy in ways that allow us to do simple chores. Its best-known form is the flow of electrons through conductors such as Fundamentals copper wires. of Electricity The word "electricity" is sometimes used to mean "electrical energy". Basic Concepts of Electricity Voltage (V) Also called electromotive force, it is the force that makes electrons flow. It's a difference in potential energy between two different points in a circuit. The amount of voltage is indicated by a unit known as the volt (V) Voltage can be compared to the water pressure in a plumbing system. Just as water flows from high pressure to low pressure, electric current flows from higher voltage to lower voltage in a circuit. Basic Concepts of Electricity Current (I) This Photo by Unknown Author is licensed under CC BY-SA The rate at which electrons flow past a point in a complete electrical circuit At its most basic, current = flow. An ampere (AM-pir), or amp, is the international unit used for measuring current. Think of electric current like the flow of water in a pipe. The more water flows through the pipe per unit of time, the higher the flow rate. Similarly, the more charge (electrons) that flows through a wire per unit of time, the higher the electric current.  Basic Concepts of Electricity Resistance (R) The measure of the opposition to current flow in an electrical circuit. Resistance is measured in ohms, symbolized by the Greek letter omega (Ω). Ohms are named after Georg Simon Ohm (1784- 1854), a German physicist who studied the relationship between voltage, current and resistance. Imagine resistance as a narrowing in a water pipe. When water flows through a narrow section of the pipe, it encounters greater resistance, and the flow rate decreases. Similarly, in an electrical circuit, higher resistance limits the flow of current. The resistance in electrical components is affected by various factors, including the material’s conductivity, length, cross-sectional area, and temperature. Understanding these factors is vital when working with electrical circuits. Basic Concepts of Electricity Power (P) The rate at which an electric circuit transfers electrical energy. Its S.I. unit is the watt (W), the general unit of power, defined as one joule per second. Standard prefixes apply to watts as with other S.I. units: thousands, millions and billions of watts are called kilowatts, megawatts and gigawatts respectively. Basic Concepts of Electricity Ohm’s Law V = IR the voltage across a conductor is directly proportional to the current flowing through it, provided all physical conditions and temperatures remain constant. Basic Concepts of Electricity Importance of Ohm’s Law In electrical installation projects, ensuring the safe and efficient flow of electricity is paramount. Ohm’s Law provides the necessary tools to calculate and predict how electrical components will behave in a circuit. This knowledge is essential for designing circuits that meet safety standards and function as intended. Basic Concepts of Electricity Practical Applications of Ohm’s Law 1.Determining Wire Size: Selecting the right wire size to carry the expected current without overheating 2.Circuit Protection: Determining rating of circuit breakers; designed to interrupt the flow of current when it exceeds safe limits, preventing electrical fires and equipment damage 3.Voltage Regulation: Designing voltage regulators that provide stable voltage outputs, crucial for sensitive electronics 4.LED Lighting: Calculating the current-limiting resistor value to prevent LED burnout  Alternating Current AC vs DC Direct Current What is AC? Alternating Current (AC) is an electric current that reverses direction periodically. It is the form of electricity commonly used in homes and businesses. AC is generated by power plants and transmitted over long distances. What is DC? Direct Current (DC) is an electric current flowing in one direction only. It is commonly used in batteries and electronic devices. DC is known for its stability and is used in many applications requiring precise voltage control. AC vs DC - Key Differences Direction - AC changes Transmission - AC is more direction periodically; DC efficient for long-distance flows in one direction. transmission. Usage - AC is used for Devices - AC is used in general power distribution; home appliances; DC is DC is used in batteries and used in electronic circuits. electronic devices. Contributions of Faraday, Tesla, and Edison Michael Faraday - Discovered electromagnetic induction, essential for Thomas Alva Edison Michael Faraday AC power generation (1847 –1931) (1791 –1867) Nikola Tesla - Developed AC power systems and the Tesla coil, revolutionizing electricity distribution. Thomas Edison - Advocated for DC power and developed the first practical electric light bulb, initiating the 'War of the Currents.' Nikola Tesla (1856 –1943) How Electricity is Transmitted Basics of Power Generation and Distribution Power Generation Power Distribution Thermal Power Plants Transmission Lines – High-voltage Hydroelectric Power Plants power lines that transport electricity Solar Power Plants over long distances. Wind Farms Substations – Transform voltage levels for safe distribution. Distribution Lines – Deliver electricity to homes and businesses. Basics of Power Generation and Distribution Alternative and Renewable energy sources RENEWABLE ENERGY Alternative and Renewable energy sources Solar energy Wind energy Geothermal energy Hydropower Ocean energy Bioenergy Solar Energy Type of energy generated by the sun Photovoltaic – common technology in harnessing solar energy Utilizes solar panels which consists of solar cells Can be used on large- or small-scale application Advantages: renewable, environmentally friendly, can be used in small-scale application Disadvantages: high initial costs, solar battery is expensive, dependent on sunlight  Harnessed by wind turbines Individual or clustered together – wind farms Wind farms – can act as power stations Typically located along coastlines, offshore, on mountains, and on fields Wind Energy Advantages: lowest environmental impact, wind farms occupy zero to minimal land Disadvantages: not common in small-scale use, typically found in large-scale use, varies in location Geothermal Energy Natural resource of heat energy from within the Earth Used for cooking, bathing, heating of spaces, and electrical power generation Harnessing this energy for electricity production is challenging Resources are limited to parts of the world: recent volcanic activities, along plate boundaries, or within crystal hot spots Philippines – largest single geothermal power plant Advantages: power plants have low carbon foot-print, sustainable and stable – available at all times, huge potential Disadvantages: production of electricity is for large- scale only – via power plants Hydropower Harnesses energy of water moving from higher to lower elevation. Oldest and largest sources of renewable energy Usually associated with dams: an enormous facility that harnesses the power of an entire river behind its walls Uses turbines to generate electricity Advantages: clean and renewable, also brings benefits outside electricity generation: flood control, irrigation support, and water supply Disadvantages: generating electricity is on a large-scale basis – via dams Ocean Energy Also known as wave energy A form of renewable energy that is harnessed through the movement of waves Waves create kinetic energy – energy through motion Utilizes turbines to generate electricity Advantages: huge potential Disadvantages: energy generated depends on size, height, length, and density of waves; for large-scale use only; development is far behind all other renewable energies Bioenergy Form of renewable energy derived from recently living organic materials known as biomass Used to produce fuels, heat, electricity, and products Energy is produced by burning biomass fuel Electricity is generated by burning biomass in a boiler to produce high-pressure steam which flows over a series of turbine blades causing them to rotate Advantages: abundant resource, helps reduce waste, reliable Disadvantages: costs, large-scale application in generating electricity, adverse environmental impacts Renewable and Non-renewable Sources Usage of renewable energy (by 2050) as proposed by the Institute for Sustainable Energy Policies (ISEP) ISEP is an independent, non-profit research organization founded in 2000 by energy experts and climate change campaigners.