An Introduction to Electrical System

Edited & Presented By : Mohammed Zaid Shaikh+97152-5953641

Electrical System

How Dependable Electricity Reaches You

Electricity Generation, Transmission and Distribution

Electricity GenerationElectricity Generation, Transmission and Distribution

Electricity Generation, Transmission and Distribution

Electricity GenerationElectricity Generation, Transmission and Distribution

Electricity Generation

Electricity generation: is the process of generating electric power from sources of energy.

The fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday. His basic method is still used today: electricity is generated by the movement of a loop of wire, or disc of copper between the poles of a magnet.Sources of Energy can be classified majorly as,1.Hydropower2.Fossil Energy (Coal, Natural gas)3.Nuclear Energy4.Wind Energy5.Renewable Energy ( Solar, Biomass)

Electricity (Power) Generation : Source of Energy

Use of Nuclear Energy in Electricity generation

Electricity Generation

Hydropower :A nonpolluting renewable energy source, hydroelectricity accounts for 20% of the electricity consumed around the world.

Electricity Generation : Source of Energy : Hydro Energy

Use of Hydro energy in Electricity Generation

Cross section of Turbine

Electrical System : Sources of Energy

Use of Nuclear Energy in Electricity generation

Electricity Generation : Source of Energy : Nuclear EnergyNuclear Energy :

Nuclear energy originates from the splitting of uranium atoms in a process called fission. At the power plant, the fission process is used to generate heat for producing steam, which is used by a turbine to generate electricity.

Electrical System : Sources of EnergyElectricity (Power) Generation : Source of Energy : Fossil EnergyFossil fuels :are formed over the course of millions of years from organic matter such as; Prehistoric animals, sea organisms, and plants as they decay, are compressed, and heated and then trapped underground where they have remained. Once discovered they are mined or pumped out to the earth’s surface and used as a source of fuel such as coal, oil, and natural gas.Fossil fuels are non-renewable sources of energy, which means once they have been burned and depleted there will be no more left for human consumption for millions of years. In other words, no human effort will result in the reproduction of new fossil fuels. Crude oil (called petroleum) is the fossil fuel used most frequently by humans, as it is easier to extract than other forms of fossil fuels.Another notorious, but somewhat “new” form of fossil fuels are bituminous sands, alternatively called oil sands, tar sands, or oil shale. Oil that is suspended in sands in a gooey mixture just beneath the topsoil is extracted by stripping entire forests of vegetation, then mixed with enormous quantities of water and chemicals which are dumped in “tailings ponds” and then turned into usable fuels. Mining bituminous sands has been called a slow-motion oil spill because of the widespread environmental destruction and inefficiency of the processes used to extract it.Extracting oil often results in oil spills which harm local soil, water systems, and wildlife

Renewable sources of energy, such as wind power, wave energy, solar power, geothermal, and low-impact hydro, are much more environmentally-safe, clean, and plentiful.Use of Nuclear Energy in Electricity generation

Electricity (Power) Generation : Source of Energy : Fossil EnergyFossil fuels :Such as coal, natural gas, and petroleum, are the basis of the modern world's energy needs. Deposits of organic material, subjected to millions of years of heat and pressure, eventually develop into natural sources of heat and energy. These ancient stores of energy power our world today, and as consumers it is important to understand why and how they influence society.

The burning of fossil fuels – including gasoline, diesel, jet fuel, kerosene, and so on – generates greenhouse gas emissions, such as carbon dioxide, which have been linked to human-caused climate change. Burning fossil fuels also results in other environmental pollutants, including air pollution, water and soil pollution, and more.

Electrical System : Sources of Energy

Use of Fossil Energy in Electricity generation

Electrical System : Sources of EnergyElectricity Generation : Source of Energy : GeothermalSuper-heated water or steam from earth's interior utilized in running the turbines of a conventional power plant to generate electricity. Such plants are usually small and suitable only for the needs of a local community. Iceland, Italy, New Zealand, Russia, and the US are among the few countries having the right-sized geothermal energy fields.

Use of Nuclear Energy in Electricity generation

Electrical System : Sources of Energy

The Definition of Photovoltaic: The word “photovoltaic” combines two terms – “photo” means light and “voltaic” means voltage. A photovoltaic system in this discussion uses photovoltaic cells to directly convert sunlight into electricity.Photovoltaic energy or a solar electric system generates electricity naturally and efficiently. To understand how photovoltaic power harnesses electricity one must first understand the basic underlying physics and the design of a photovoltaic device. This is a fully functional system that can be used as a renewable resource in generating electric power. The DOE or the Solar Energy Technologies Program of the United States Department of Energy is constantly adding to the expertise and knowledge of the field of photovoltaic energy. As improvements are made in technology, in the field of solar energy, there is an abundance of power derived from the energy of the sun. Photovoltaic technology studies how the sun’s energy can essentially work for us as a power source.

Electricity Generation : Source of Energy : Photovoltaic Energy

Electrical System : Sources of EnergyElectricity Generation : Source of Energy : Wind Energy

Wind energy is energy collected from motion caused by heavy winds. Wind energy is collected in turbines with propellers that spin when the wind blows and turn the motion of the propeller into energy that can be used in the electrical grid. Wind energy is a clean, renewable energy source that is abundant in windy areas. Large wind farms are often located outside of cities, supplying power for electrical grids within the city.Wind turbines come in a variety of sizes that can be used to supply power to individual buildings or feed electricity into a grid system. They must be located above nearby buildings and trees to work effectively for a home or building. Considerations to be taken when installing a wind turbine include location, average wind speed, the height of the surrounding buildings and trees, and the building’s connection to the electrical grid.

Electrical System : Sources of EnergyElectricity Generation : Source of Energy : Wind EnergyThe wind is one of the cleanest sources of energy, and because it is a naturally generated resource, it is also the most abundant energy source on the planet today.  Wind power is energy that is created through the conversion of wind into forms that are more practically useful, such as electricity.  Wind energy is currently supplying as much as 1% of the world’s electricity use, however the power of wind energy could potentially supply as much as 20% of global electricity.

Wind Diagram The Process Behind Wind Energy is Pretty Simple

Electrical System : Sources of EnergyElectricity Generation : Source of Energy : Ocean Thermal Energy

Ocean Thermal Energy Conversion

Ocean Thermal Energy Conversion (OTEC) uses the temperature difference between cooler deep and warmer shallow or surface ocean waters to run a heat engine and produce useful work, usually in the form of electricity. However, the temperature differential is small and this impacts the economic feasibility of ocean thermal energy for electricity generation.

Electrical System : Sources of Energy

Electricity generation: is the process of generating electric power from sources of energy..The fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday. His basic method is still used today: electricity is generated by the movement of a loop of wire, or disc of copper between the poles of a magnet.

Sources of Energy can be classified as,1.Hydro Energy 2.Fossil Energy 3.Nuclear Energy4.Renewable Energy

Power Plant using Nuclear Fission to generate Electricity

Power Generation : Source of Energy : Power Plants

Electricity Generation & Distribution Electricity(Power) Generation, Distribution

Generating electricityGenerators are the devices that transfer kinetic energy into electrical energy. Mains electricity is produced by generators.

Turning generators directly Generators can be turned directly, for example by:1.wind turbines2.hydroelectric turbines3.wave and tidal turbines

When electricity is generated using wave, wind, tidal or hydroelectric power (HEP) there are two steps involved :1.The turbine turns a generator. 2.Electricity is produced.

Electricity Generation & Distribution Electricity(Power) Generation, Distribution

Generating electricityGenerators are the devices that transfer kinetic energy into electrical energy. Mains electricity is produced by generators.Turning generators indirectlyGenerators can be turned indirectly using fossil or nuclear fuels. The heat from the fuel boils water to make steam, which expands and pushes against the blades of a turbine. The spinning turbine then turns the generator.

These are the steps by which electricity is generated from fossil fuels:Heat is released from a primary energy source fuel and boils the water to make steam . The steam turns the turbine. The turbine turns a generator and electricity is produced.The electricity goes to the transformers to produce the correct voltage.

Electrical System : Sources of Energy

Sources of Energy can be classified as,1.Hydro Energy 2.Fossil Energy 3.Nuclear Energy4.Renewable Energy

Fossil Energy : Fossil fuels (coal, natural gas, and petroleum) are the basis of the modern world's energy needs. Deposits of organic material, subjected to millions of years of heat and pressure, eventually develop into natural sources of heat and energy. These ancient stores of energy power our world today, and as consumers it is important to understand why and how they influence society.

Power Generation : Source of Energy

Fossil fuel

A Traditional Fossil Energy Source

Electrical System : Electrcity Generation

Electricity is most often generated at a power station by electromechanical generators, primarily driven by heat engines fueled by chemical combustion or nuclear fission but also by other means such as the kinetic energy of flowing water and wind.

There are many other technologies that can be and are used to generate electricity such as solar photovoltaics and geothermal power.

For electric utilities, it is the first process in the delivery of electricity to consumers. The other processes, electricity transmission, distribution, and electrical power storage and recovery using pumped-storage methods are normally carried out by the electric power industry.

A coal-fired power plant in Laughlin, Nevada U.S.A.

Jeddah Power Plant ,will use super critical BOILERS , K.S.A

Power / Electricity Generation : Power Plants-Stations

Wind turbines in Texas, USA

Electrical System : Electrcity Generation

Thermal Power PlantsThermal power plants work by heating water into steam, using that steam to drive a turbine, and the turbine to run an electrical generator. In most thermal power plant designs, fossil fuels are burned to provide the heat.

Nuclear Power PlantsIn a nuclear power plants, it is the fission of heavy, unstable elements that provides the source of heat for boiling the water and making steam. In all other respects, the actual process of generating electricity is the same as in a conventional thermal power plant

Power / Electricity Generation :

Thermal Power Plants

Japan's Oi Nuclear Power Plant in Fukui prefecture

Electrical System : Electrcity Generation

Sources of electricity in the U.S. in 2009 fossil fuel generation (mainly coal) was the largest source.

Sources of electricity in France in 2006; nuclear power was the main source.

Power / Electricity Generation : Source

Electrical System : Power Station

A power station (also referred to as a generating station, power plant, powerhouse or generating plant) is an industrial facility for the generation of electric power. At the center of nearly all power stations is a generator, a rotating machine that converts mechanical power into electrical power by creating relative motion between a magnetic field and a conductor.

The energy source harnessed to turn the generator varies widely. It depends chiefly on which fuels are easily available, cheap enough and on the types of technology that the power company has access to.Most power stations in the world burn fossil fuels such as coal, oil, and natural gas to generate electricity, and some use nuclear power, but there is an increasing use of cleaner renewable sources such as solar, wind, wave and hydroelectric. Central power stations produce AC power, after a brief Battle of Currents in the 19th century demonstrated the advantages of AC distribution. Central Utah Coal Fired Power

Plant

Big Bend Power Station

Power / Electricity Generation : Source

Electricity –Electrical Energy

There are seven fundamental methods of directly transforming other forms of energy into electrical energy:

1.Static electricity was the first form discovered and investigated, and the electrostatic generator is still used even in modern devices such as the Van de Graaff generator and MHD generators. Charge carriers are separated and physically transported to a position of increased electric potential.Static electricity, from the physical separation and transport of charge (examples: triboelectric effect and lightning)

2.Electromagnetic induction, where an electrical generator, dynamo or alternator transforms kinetic energy (energy of motion) into electricity. This is the most used form for generating electricity and is based on Faraday's law. It can be experimented by simply rotating a magnet within closed loops of a conducting material (e.g. copper wire)

Methods Transforming Energy Electrical Energy

Electricity –Electrical Energy

3.Electrochemistry, the direct transformation of chemical energy into electricity, as in a battery, fuel cell or nerve impulse

4.Photoelectric effect, the transformation of light into electrical energy, as in solar cells

5.Thermoelectric effect, the direct conversion of temperature differences to electricity, as in thermocouples, thermopiles, and thermionic converters.

6.Piezoelectric effect, from the mechanical strain of electrically anisotropic molecules or crystals. Researchers at the US Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a piezoelectric generator sufficient to operate a liquid crystal display using thin films of M13 bacteriophage .

7..Nuclear transformation, the creation and acceleration of charged particles (examples: betavoltaics or alpha particle emission)

Methods Transforming Energy Electrical Energy

Electricity Generation

Turbines : A turbine is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. A turbine is a turbomachine with at least one moving part called a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades so that they move and impart rotational energy to the rotor. Early turbine examples are windmills and water wheels.

Methods Transforming Energy Electrical Energy : Turbines

Heavy Duty Gas Turbine Generator

Electricity Generation

In early days Water wheels and Wind mill where used to convert the energy of free flowing Water and wind into useful form of power or rotational energy by means of fallings water or vanes (sails)

Turbines : Early days TurbinesA water wheel is a machine for converting the energy of free-flowing or falling water into useful forms of power, often in a watermill.

A windmill is a machine that converts the energy of wind into rotational energy by means of vanes called sails

Wind mill, Amsterdam, Netherlands, built in 1757,

A waterwheel standing 42ft (13m) high powers the Old Mill at Berry College in Rome, Georgia, USA

Electricity Generation

Sources of driving Turbines include;Steam :Water is boiled byNuclear fissionThe world runs on electricity, and nuclear power is one method of generating electricity. It makes electricity using the same principles as fossil fuel plants. The fuel source creates heat to turn water into steam. The steam flows against the fins of a turbine causing it to spin. Steam drives the turbine. In a nuclear power plant, fission creates the heat to turn water into steam.

Turbines : Type of Turbines based on Sources : Steam

Water Turbine Grandcoulee

• Nuclear fission

Electricity Generation

Sources of driving TURBINES include:Steam – Water is boiled by•Nuclear fission•The burning of fossil fuels (coal, natural gas, or petroleum). In hot gas (gas turbine), turbines are driven directly by gases produced by the combustion of natural gas or oil. Combined cycle gas turbine plants are driven by both steam and natural gas. They generate power by burning natural gas in a gas turbine and use residual heat to generate additional electricity from steam. These plants offer efficiencies of up to 60%.

Methods Transforming Energy Electrical Energy : Turbines

Nuclear Turbines versus Coal Turbines

Nuclear Turbines versus Coal Turbines Sandia's Closed Loop

Carbon Dioxide Gas Turbine

Oil or Natural Gas to Generate Heat. In a Nuclear Energy Facility,enec.gov.ae

Electricity Generation

Sources of driving TURBINES include:•Renewables. Solar thermal

energy (the sun as the heat source): solar parabolic troughs and solar power towers concentrate sunlight to heat a heat transfer fluid, which is then used to produce steam.

Methods Transforming Energy Electrical Energy : Turbines

Solar Thermal Plants use the sun's heat to run steam turbines

Solar Thermal Energy

Sunrise on Solar Thermal Research Hub

Solar Power Tower

Electricity Generation

Sources of driving TURBINES include:•Renewables. Geothermal power.

Either steam under pressure emerges from the ground and drives a turbine or hot water evaporates a low boiling liquid to create vapour to drive a turbine.

Methods Transforming Energy Electrical Energy : Turbines

Blue Lagoon Geothermal Power Plant, Iceland

MATSUKAWA Geothermal Power Station Iwate, JAPAN

Geothermal Power Turbine Geothermal Power Turbine

Electricity Generation

Sources of driving TURBINES include:•Renewables. Ocean thermal

energy conversion (OTEC ): uses the small difference between cooler deep and warmer surface ocean waters to run a heat engine (usually a turbine).

Methods Transforming Energy Electrical Energy : Turbines

The Ocean Thermal Energy Conversion

The Ocean Thermal Energy Conversion-Via the Guardian & the Telegraph

Ocean Thermal Energy Conversion is based on the work of ..

Electricity Generation

Sources of driving TURBINES include:•Renewable.

Biomass:What is biomass?Energy from biomass is

produced from organic matter of recent origin. It does not include fossil fuels, which have taken millions of years to form. Although there are many different forms of biomass, the focus here is wood fuel as the most common fuel option for heat production.

Methods Transforming Energy Electrical Energy : Turbines

GE's Biomass Steam Turbine Product Line Offers a Compact,

Biomass Extraction Cum Condensing Turbine.

Operates a Proprietary Direct Fired Biomass Fueled Gas Turbine

Turbine house, generator in a biomass co-generation plant,

Electricity Generation

TurbinesBiomass:

How is it carbon neutral?As the wood is burned, CO2 is

released, but this will be equivalent to the amount absorbed by the plant when it was growing. There are emissions associated with the production and transportation of wood fuel, but if transportation distances are short (no more than 25 miles), the use of wood to generate heat is generally regarded as being carbon neutral.

To also be sustainable, the rate of use must be the same as or less than the rate of natural replenishment. It is therefore important to ensure that fuel supply is from a renewable source.

Methods Transforming Energy Electrical Energy : Turbines

Electricity Generation

TurbinesOther renewable sources:

Water (hydroelectric) - Turbine blades are acted upon by flowing water, produced by hydroelectric dams or tidal forces.Wind - Most wind turbines generate electricity from naturally occurring wind. Solar updraft towers use wind that is artificially produced inside the chimney by heating it with sunlight, and are more properly seen as forms of solar thermal energy

Methods Transforming Energy Electrical Energy : Turbines

Hydroelectric Water Turbine

Hydroelectricity Water Turbine

Water Turbine

water turbine that can generate pollution-free electricity for a city.

Electricity Generation

Reciprocating enginesSmall electricity generators are often powered by reciprocating engines burning diesel, biogas or natural gas. Diesel engines are often used for back up generation, usually at low voltages. However most large power grids also use diesel generators, originally provided as emergency back up for a specific facility such as a hospital, to feed power into the grid during certain circumstances. Biogas is often combusted where it is produced, such as a landfill or wastewater treatment plant, with a reciprocating engine or a microturbine, which is a small gas turbine.

Methods Transforming Energy Electrical Energy : Turbines

Advanced reciprocating engines will run at higher pressures and higher ...

Reciprocating engine

Electricity Generation

Photovoltaic panelsUnlike the solar heat concentrators mentioned above, photovoltaic panels convert sunlight directly to electricity. Although sunlight is free and abundant, solar electricity is still usually more expensive to produce than large-scale mechanically generated power due to the cost of the panels. Low-efficiency silicon solar cells have been decreasing in cost and multijunction cells with close to 30% conversion efficiency are now commercially available. Over 40% efficiency has been demonstrated in experimental systems.[8] Until recently, photovoltaics were most commonly used in remote sites where there is no access to a commercial power grid, or as a supplemental electricity source for individual homes and businesses. Recent advances in manufacturing efficiency and photovoltaic technology, combined with subsidies driven by environmental concerns, have dramatically accelerated the deployment of solar panels. Installed capacity is growing by 40% per year led by increases in Germany, Japan, California and New Jersey.

Methods Transforming Energy Electrical Energy : Turbines

Electricity generation with wind turbines, photovoltaics and biogas

Solar photovoltaic panels and micro wind turbines produce electricity

Electricity Generation

Other generation methods :Various other technologies have been studied and developed for power generation. Solid-state generation (without moving parts) is of particular interest in portable applications. This area is largely dominated by thermoelectric (TE) devices, though thermionic (TI) and thermophotovoltaic (TPV) systems have been developed as well. Typically, TE devices are used at lower temperatures than TI and TPV systems. Piezoelectric devices are used for power generation from mechanical strain, particularly in power harvesting. Betavoltaics are another type of solid-state power generator which produces electricity from radioactive decay. Fluid-based magnetohydrodynamic (MHD) power generation has been studied as a method for extracting electrical power from nuclear reactors and also from more conventional fuel combustion systems. Osmotic power finally is another possibility at places where salt and sweet water merges (e.g. deltas, ...) Electrochemical electricity generation is also important in portable and mobile applications. Currently, most electrochemical power comes from closed electrochemical cells ("batteries"),[9] which are arguably utilized more as storage systems than generation systems; but open electrochemical systems, known as fuel cells, have been undergoing a great deal of research and development in the last few years. Fuel cells can be used to extract power either from natural fuels or from synthesized fuels (mainly electrolytic hydrogen) and so can be viewed as either generation systems or storage systems depending on their use.

Methods Transforming Energy Electrical Energy : Turbines

Electricity Generation

Photovoltaic panelsUnlike the solar heat concentrators mentioned above, photovoltaic panels convert sunlight directly to electricity. Although sunlight is free and abundant, solar electricity is still usually more expensive to produce than large-scale mechanically generated power due to the cost of the panels. Low-efficiency silicon solar cells have been decreasing in cost and multijunction cells with close to 30% conversion efficiency are now commercially available. Over 40% efficiency has been demonstrated in experimental systems.[8] Until recently, photovoltaics were most commonly used in remote sites where there is no access to a commercial power grid, or as a supplemental electricity source for individual homes and businesses. Recent advances in manufacturing efficiency and photovoltaic technology, combined with subsidies driven by environmental concerns, have dramatically accelerated the deployment of solar panels. Installed capacity is growing by 40% per year led by increases in Germany, Japan, California and New Jersey

Methods Transforming Energy Electrical Energy : Turbines

Electricity Generation

Photovoltaics (PV) is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Materials presently used for photovoltaics include monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride, and copper indium gallium selenide/sulfide. Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years.

Nellis Solar Power Plant at Nellis Air Force Base in the USA. These panels track the sun in one axis

Methods Transforming Energy Electrical Energy : Turbines

High voltage

High voltage transmissionHigh voltage is used for electric power transmission to reduce the energy lost in the

resistance of the wires. For a given quantity of power transmitted and size of conductor, doubling the voltage will deliver the same power at only half the current. Since the power lost as heat in the wires is proportional to the square of the current, but does not depend on the voltage, doubling the voltage reduces the line-loss loss per unit of electrical power delivered by a factor of 4. While power lost in transmission can also be reduced by increasing the conductor size, larger conductors are heavier and more expensive.

High voltages cannot easily be used for lighting and motors, and so transmission-level voltages must be reduced to values compatible with end-use equipment. Transformers are used to change the voltage level in alternating current (AC) transmission circuits. AC became dominant after the War of Currents competition between the direct current (DC) system of Thomas Edison and the AC system of George Westinghouse because transformers made voltage changes practical and generators using AC were more efficient than those using DC.

Practical conversion between AC and high power high voltage DC became possible with the development of power electronics devices such as mercury arc valves and, starting in the 1970s, semiconductor devices such as thyristors and later variants such as integrated gate-commutated thyristors (IGCTs), MOS controlled thyristors (MCTs) and insulated-gate bipolar transistors (IGBT).

High voltage

Overhead line systemsThe capacitive effect of long underground or

undersea cables in AC transmission applications also applies to AC overhead lines, although to a much lesser extent. Nevertheless, for a long AC overhead transmission line, the current flowing just to charge the line capacitance can be significant, and this reduces the capability of the line to carry useful current to the load at the remote end. Another factor that reduces the useful current carrying ability of AC lines is the skin effect, which causes a non-uniform distribution of current over the cross-sectional area of the conductor. Transmission line conductors operating with HVDC current do not suffer from either of these constraints. Therefore, for the same conductor losses (or heating effect), a given conductor can carry more current to the load when operating with HVDC than AC. Overhead Transmission Tower

Power linesElectrical transmission and distribution lines for electric power always use voltages significantly higher than 50 volts, so contact with or close approach to the line conductors presents a danger of electrocution. Contact with overhead wires is a frequent cause of injury or death. Metal ladders, farm equipment, boat masts, construction machinery, aerial antennas, and similar objects are frequently involved in fatal contact with overhead wires. Digging into a buried cable can also be dangerous to workers at an excavation site. Digging equipment (either hand tools or machine driven) that contacts a buried cable may energize piping or the ground in the area, resulting in electrocution of nearby workers. A fault in a high-voltage transmission line or substation may result in high currents flowing along the surface of the earth, producing an earth potential rise that also presents a danger of electric shock.Unauthorized persons climbing on power pylons or electrical apparatus are also frequently the victims of electrocution.[6] At very high transmission voltages even a close approach can be hazardous, since the high voltage may spark across a significant air gap.

Electrical Transmission and Distribution Line

High voltage

Elements of a Substatio

Substations generally have switching, protection and control equipment, and transformers. In a large substation, circuit breakers are used to interrupt any short circuits or overload currents that may occur on the network. Smaller distribution stations may use recloser circuit breakers or fuses for protection of distribution circuits. Substations themselves do not usually have generators, although a power plant may have a substation nearby. Other devices such as capacitors and voltage regulators may also be located at a substation.

Substations may be on the surface in fenced enclosures, underground, or located in special-purpose buildings. High-rise buildings may have several indoor substations. Indoor substations are usually found in urban areas to reduce the noise from the transformers, for reasons of appearance, or to protect switchgear from extreme climate or pollution conditions.

Where a substation has a metallic fence, it must be properly grounded to protect people from high voltages that may occur during a fault in the network. Earth faults at a substation can cause a ground potential rise. Currents flowing in the Earth's surface during a fault can cause metal objects to have a significantly different voltage than the ground under a person's feet; this touch potential presents a hazard of electrocution.

Elements of a Substation

A:Primary power lines' side B:Secondary power lines' side:1.Primary power lines 2.Ground wire 3.Overhead lines 4.Transformer for measurement of electric voltage 5.Disconnect switch 6.Circuit breaker 7.Current transformer 8.Lightning arrester 9.Main transformer 10.Control building 11.Security fence 12.Secondary power lines

Substation

A substation is a part of an electrical generation, transmission, and distribution system. Substations transform voltage from high to low, or the reverse, or perform any of several other important functions. Between the generating station and consumer, electric power may flow through several substations at different voltage levels.

Substations may be owned and operated by an electrical utility, or may be owned by a large industrial or commercial customer. Generally substations are un-attended, relying on SCADA for remote supervision and control.

A substation may include transformers to change voltage levels between high transmission voltages and lower distribution voltages, or at the interconnection of two different transmission voltages. The word substation comes from the days before the distribution system became a grid. As central generation stations became larger, smaller generating plants were converted to distribution stations, receiving their energy supply from a larger plant instead of using their own generators. The first substations were connected to only one power station, where the generators were housed, and were subsidiaries of that power station

A 50 Hz electrical substation in Melbourne. This is showing three of the five 220 kV/66 kV transformers, each with a capacity of 185 MVA

Transformer

A transformer is a power converter that transfers energy between two electrical circuits by inductive coupling between two or more windings. A varying current in the primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic flux through the secondary winding. This varying magnetic flux induces a varying electromotive force (EMF), or "voltage", in the secondary winding. This effect is called inductive coupling.If a load is connected to the secondary winding, current will flow in this winding, and electrical energy will be transferred from the primary circuit through the transformer to the load. Transformers may be used for AC-to-AC conversion of a single power frequency, or for conversion of signal power over a wide range of frequencies, such as audio or radio frequencies. In an ideal transformer, the induced voltage in the secondary winding (Vs) is in proportion to the primary voltage (Vp) and is given by the ratio of the number of turns in the secondary (Ns) to the number of turns in the primary (Np) as follows:

Transformer

Sub-station Transformers :This type of transformer is used in sub stations to transfer the incoming voltage to the next voltage level. It can be system or auto transformer with two/three windings. In general it is equipped with On load tap changers and are connected to transmission grids by bushings and cables.The system/auto transformer is built in core form. HV/LV windings are galvanically separated for system transformer while they are Auto connected for auto transformer.  

Liquid Filled Power Transformers upto 200MVA,220KV

Transformer : Substation

132kV substation is part of transmission and distribution of power in which the transmission voltage is 132kV. The substation is for stepping down or stepping up of the voltages to the required voltage. the substation also serves as a place where the transmission lines can be isolated, controlled and monitored. The substation consists of different equipment that is used to regulate, monitor and distribute the required power.

132 KV Substation

132 KV Substation

Transformer : Substation

A 132/11 kV substation

11kV/400V Package Substations Have Ratings Of 500kVA

Primary substation - when the transformer is HV/MV or MV/MV. e.g. substation designed for 132kV/33kV or 230kV/22kV or 33kV/11kV etcstepped down for MV distribution (mainly for utilities and heacy industries)Secondary substation - when the transformer is HV/LV or MV/LV. e.g. substation designed for 11kV/400V or 6.6kV/400V etcstepped down for LV distribution (mainly for residential, commercial) sometime referred to as a kiosk substation.

132/11-kV Substations in North of Kuwait

Transformer

By appropriate selection of the ratio of turns, a transformer thus enables an alternating current (AC) voltage to be "stepped up" by making Ns greater than Np, or "stepped down" by making Ns less than Np. The windings are coils wound around a ferromagnetic core, air-core transformers being a notable exception.Transformers range in size from a thumbnail-sized coupling transformer hidden inside a stage microphone to huge units weighing hundreds of tons used in power stations, or to interconnect portions of power grids. All operate on the same basic principles, although the range of designs is wide. While new technologies have eliminated the need for transformers in some electronic circuits, transformers are still found in nearly all electronic devices designed for household ("mains") voltage. Transformers are essential for high-voltage electric power transmission, which makes long-distance transmission economically practical.

High-voltage-transformer--Newcastle-upon-Tyne_web

High Voltage Transformer

Switchgear

In an electric power system, switchgear is the combination of electrical disconnect switches, fuses or circuit breakers used to control, protect and isolate electrical equipment. Switchgear is used both to de-energize equipment to allow work to be done and to clear faults downstream. This type of equipment is important because it is directly linked to the reliability of the electricity supply.The very earliest central power stations used simple open knife switches, mounted on insulating panels of marble or asbestos. Power levels and voltages rapidly escalated, making opening manually operated switches too dangerous for anything other than isolation of a de-energized circuit. Oil-filled equipment allowed arc energy to be contained and safely controlled. By the early 20th century, a switchgear line-up would be a metal-enclosed structure with electrically operated switching elements, using oil circuit breakers. Today, oil-filled equipment has largely been replaced by air-blast, vacuum, or SF6 equipment, allowing large currents and power levels to be safely controlled by automatic equipment incorporating digital controls, protection, metering and communications.

High voltage switchgear

High Voltage Switchgear

A section of a large switchgear panel, in this case, used to control on-board casino boat power generation.

High voltage switchgear was invented at the end of the 19th century for operating motors and other electric machines.[1] The technology has been improved over time and can be used with voltages up to 1,100 kV.[2]

Typically, the switchgear in substations is located on both the high voltage and the low voltage side of large power transformers. The switchgear on the low voltage side of the transformers may be located in a building, with medium-voltage circuit breakers for distribution circuits, along with metering, control, and protection equipment. For industrial applications, a transformer and switchgear line-up may be combined in one housing, called a unitized substation or USS

Transformer

A delta-wye (Δ-Y) transformer is a type of three-phase electric power transformer design that employs Delta on primary and wye/star on secondary. A neutral wire can be provided on wye output side. It can be a single three-phase transformer, or built from three independent single-phase units. The term Delta-Wye transformer is used in North America, and Delta-Star system in Europe.Delta-wye transformers are common in commercial, industrial, and high-density residential locations, to supply three-phase distribution systems.An example would be a distribution transformer with a delta primary, running on three 11kV phases with no neutral or earth required, and a star (or wye) secondary providing a 3-phase supply at 400 V, with the domestic voltage of 230 available between each phase and an earthed neutral point.

Star -Delta Transformer

Transformer

For three-phase supplies, a bank of three individual single-phase transformers can be used, or all three phases can be incorporated as a single three-phase transformer. In this case, the magnetic circuits are connected together, the core thus containing a three-phase flow of flux.[58] A number of winding configurations are possible, giving rise to different attributes and phase shifts.[84] One particular polyphase configuration is the zigzag transformer, used for grounding and in the suppression of harmonic currents.,[85] Three-phase step-down transformer mounted

between two utility poles

Transformer

Pole-mounted distribution transformer with center-tapped secondary winding. This type of transformer is commonly used in North America to provide 120/240 volt "split-phase" power for residential and light commercial use. Note that the center "neutral" terminal is grounded to the transformer

Generator Synchronizing & Control Panels

Synchronization panels are mainly designed and used to meet power system requirements. These panels provide manual as well as automatic synchronizing function for one or more generator breakers. They are widely used in synchronizing generators and offering multiplexing solutions

Distribution Board

The low-voltage board meets all the requirements of industrial plant engineering. It features compact and robust switchgear cabinet technology, which reflects the experience of has gained from using many different systems. The mechanical design is based on individual switchboard cabinet panels built from tried and tested, commercially available standard switchgear cabinet systems, e.g., made by Cubic™ or Rittal™.Our Low Voltage system provides compact solutions for confined spaces. They are well designed and offer plenty of space for performing terminal connection work.The switchboard offers a high level of operational reliability. All systems are type-tested in accordance with the latest production and quality criteria of DIN EN 60439, Part 1, form of inner separation 2b.They are manufactured in SEG own production facilities in accordance with the latest production and quality criteria of DIN ISO 9001.Mechanical FeaturesBesides the use of conventional fixed mounted design, the Low system concept also allows a standardized draw out assembly. No matter what type of construction is used, all switchgear cabinet panels are designed as individual segments and built ready mounted as a subsystem in all panels. The individual subsystems are easy to connect on site via strap joints.The heat generated by the individual system components is dissipated externally via a ventilation system. Full-width perforated plates (cross flow division into compartments) between each panel result in optimum flow conditions and good heat dissipation.

LV / MV / MCC Switch Board Control Panels

Distribution BoardLV / MV / MCC Switch Board Control Panels

Busbar SystemThe busbar system is mounted on the system cabinets (on top design). It is designed to inhibit eddy currents. The busbar compartment is separated from the other built-in compartments by partition plates. One person can easily mount the busbar subsystem for each panel. The “on top” design not only reduces the installation costs, it also provides convenient access to the busbar terminal points for later inspection work.

Distribution Board

MCC Panels are Motor Control Centers consisting of the circuit breakers, starters and its controls which are generally having higher capacity to feed larger loads.MCC Panels which basically consist of starters are used to start or control the motors, water pumps, compressors, fans, conveyer belts etc. A motor control center (MCC) is an assembly of one or more enclosed sections having a common power bus and principally containing motor control units. Motor control centers are in modern practice a factory assembly of several motor starters. A motor control center can include variable frequency drives, programmable controllers, and metering and may also be the electrical service entrance for the building. Motor control centers are usually used for low voltage three-phase alternating current motors from 208 V to 600 V. Medium-voltage motor control centers are made for large motors running at 2300 V to around 15000 V, using vacuum contactors for switching and with separate compartments for power switching and control.

MCC Panel

MCC Panel

Distribution Board

Power distribution board is a system by which the electrical energy is transmitted via branches to reach the exact user. It is categorized into LV panels/ MDBs, SMDBs and the final Dbs.     • Main Distribution board: The LV Panels/mains distribution originates at the mains intake        which is located next to the transformer and radiates out throughout in a branching or tree       like fashion.      • Sub Main Distribution board: The Main Distribution board then feeds a Sub main distribution board which is installed half way        through the mains distribution system, generally at the point where a large distribution cable terminates, and several smaller         sub-circuits start      • Final distribution board: The final distribution board is generally installed locally to where the electrical power is used        (point of utilization).The power distribution boards are used for plants, industries, domestic purpose etc

Distribution Board : Components

Distribution Board

The electrical wiring is carried out to distribute current from a single source of supply to various circuits, such arrangement of circuits is made inside an enclosure called Distribution Board. The Distribution Board is not merely an enclosure but a comprehensive system in itself, comprising of copper bus bars, brass neutral links, earth links to facilitate effective distribution of current. It incorporates safety devices such as MCBs, ELCBs and Isolators, which serves to protect the installation. A wide range of compact, elegant & economical DBs with unique features, designed & engineered to provide user safety, convenience and operational / maintenance advantages are offered.Aesthetically superior DBs to suit the style of your home decor. Complete range of DBs with detachable gland plates at the top and bottom with knockouts on the sides of DB to increase the flexibility of cables /conduit entry from all directions. Ready to use DBs that are supplied with Neutral Links, Earth Links, Bus Bar and inter connecting wire/links.

Distribution Board

Distribution Board

Power Distribution Board consists of Main Incomer of 250A/400A/630A etc upto 2500A or 4000A with metering and indications and various numbers of outgoing feeders of different ratings . Provision of Horizontal / Vertical Busbars of adequate rating and suitable cable alleys so as to terminate the cables from top/bottom side.The design of cabinet is suitable for the location available which may be completed erected and commissioned at site. The photograph shows internal arrangement of components and Bus bars which is designed for ease of maintenance and sufficient space for cooling. All the safety precautions are duly taken along with strongly supported busbars so as to sustain the short circuits on outgoing side if any.

Power Distribution Boards (PDB) & Main Distribution Boards (MDB)

Distribution Board

Sub Main Distribution Boards (SMDB)

Extremely economical for reducing Power cabling costs. Installation generally at load centers.Sheet steel enclosed with Powder coating In Cabinet (Wall mounting) or Feeder Pillar (Floor mounting) design. Outdoor or Indoor type with suitable protection. Ample space for ease of cable Termination. Complete with MCCB/Switch/HRC fuses etc. Customized to user requirements.

Sub Main Distribution Boards

Distribution Board

Final Distribution Boards :It is a final connection of “domestic” or small appliance loads that faults such as loose connections are liable to occur. CEL, over the years, has developed a system of final distribution both wired and back pan busbar types rigidly connected and also available brought to terminals for field connection. Floor and wall mounted of single and or multi cubicle design available. Separate relay sections for emergency lighting, outside lighting, heating, water heating, etc. are part of the overall package.

Final Distribution Boards

High voltage

High Voltage (Definition):The use of the term high voltage usually (though not always) means electrical energy at voltages high enough to inflict harm or death upon living things. Equipment and conductors that carry high voltage warrant particular safety requirements and procedures. In certain industries, high voltage means voltage above a particular threshold (see below) .

High voltage is used in electrical power distribution, in cathode ray tubes, to generate X-rays and particle beams, to demonstrate arcing, for ignition, in photomultiplier tubes, and in high power amplifier vacuum tubes and other industrial and scientific applications

High voltages may lead to electrical breakdown, resulting in an electrical discharge as illustrated by the plasma filaments streaming from a Tesla coil.

The numerical definition of high voltage depends on context. Two factors considered in classifying a voltage as "high voltage" are the possibility of causing a spark in air, and the danger of electric shock by contact or proximity. The definitions may refer to the voltage between two conductors of a system, or between any conductor and ground.In electric power transmission engineering, high voltage is usually considered any voltage over approximately 35,000 volts. This is a classification based on the design of apparatus and insulation.The International Electrotechnical Commission and its national counterparts (IET, IEEE, VDE, etc.) define high voltage as above 1000 V for alternating current, and at least 1500 V for direct current—and distinguish it from low voltage (50–1000 V AC or 120–1500 V DC) and extra-low voltage (<50 V AC or <120 V DC) circuits. This is in the context of building wiring and the safety of electrical apparatus.In the United States 2005 National Electrical Code (NEC), high voltage is any voltage over 600 V (article 490.2). British Standard BS 7671:2008 defines high voltage as any voltage difference between conductors that is higher than 1000 V AC or 1500 V ripple-free DC, or any voltage difference between a conductor and Earth that is higher than 600 V AC or 900 V ripple-free DC.

High Voltage Definition

Electricians may only be licensed for particular voltage classes, in some jurisdictions. [1] For example, an electrical license for a specialized sub-trade such as installation of HVAC systems, fire alarm systems, closed circuit television systems may be authorized to install systems energized up to only 30 volts between conductors, and may not be permitted to work on mains-voltage circuits. The general public may consider household mains circuits (100–250 V AC), which carry the highest voltages they normally encounter, to be high voltage.Voltages over approximately 50 volts can usually cause dangerous amounts of current to flow through a human being who touches two points of a circuit—so safety standards, in general, are more restrictive around such circuits. The definition of extra high voltage (EHV) again depends on context. In electric power transmission engineering, EHV refers to equipment that carries more than 345,000 volts between conductors. In electronics systems, a power supply that provides greater than 275,000 volts is called an EHV Power Supply, and is often used in experiments in physics.The accelerating voltage for a television cathode ray tube may be described as extra-high voltage or extra-high tension (EHT), compared to other voltage supplies within the equipment. This type of supply ranges from >5 kV to about 50 kV.[citation needed]

In digital electronics, a logical high voltage is the one that represents a logic 1. It is typically represented by a voltage higher than the corresponding range for logic 0, but the difference may be less than a volt for some logic families. Older systems such as TTL used 5 volts, newer computers typically use 3.3 volts (LV-TTL) or even 1.8 volts.

High voltage

High voltage

For high-voltage and extra-high-voltage transmission lines, specially trained personnel use so-called "live line" techniques to allow hands-on contact with energized equipment. In this case the worker is electrically connected to the high-voltage line but thoroughly insulated from the earth so that he is at the same electrical potential as that of the line. Since training for such operations is lengthy, and still presents a danger to personnel, only very important transmission lines are subject to maintenance while live. Outside these properly engineered situations, insulation from earth does not guarantee that no current flows to earth—as grounding or arcing to ground can occur in unexpected ways, and high-frequency currents can burn even an ungrounded person. Touching a transmitting antenna is dangerous for this reason, and a high-frequency Tesla Coil can sustain a spark with only one endpoint.)

Protective equipment on high-voltage transmission lines normally prevents formation of an unwanted arc, or ensures that it is quenched within tens of milliseconds. Electrical apparatus that interrupts high-voltage circuits is designed to safely direct the resulting arc so that it dissipates without damage. High voltage circuit breakers often use a blast of high pressure air, a special dielectric gas (such as SF6 under pressure), or immersion in mineral oil to quench the arc when the high voltage circuit is broken.

High voltage : Definitions

HIGH VOLTAGE:  High voltage starts at the point where designers have to consider additional technical issues, and where there are significantly fewer component suppliers

to choose from.  See also additional definitions.ISOLATION:  The electrical separation between two conductors or two circuits.ISOLATION VOLTAGE:  The maximum dc or ac voltage that may be continuously applied between two isolated conductors or two circuits.PRIMARY CIRCUIT:  A circuit electrically connected to the input or source of power to the device.  See also Secondary Circuit.SAFETY GROUND:  A conductive path to earth that is designed to protect persons from electrical shock by shunting away any dangerous currents that might occur due to malfunction or accident.SECONDARY CIRCUIT:  A circuit that is electrically isolated from the input or source of power to the device.  See also Primary Circuit.STANDOFF:  A mechanical support insulator used to support a wire or component away from its mounting surface.TRACKING:  Marks made on a surface that experienced flashover.WITHSTAND VOLTAGE:  See Dielectric Withstand Voltage.WORKING VOLTAGE:  The specified or actual operating voltage applied between two conductors, circuits or a component.

High voltage

Why we need High Voltage Transmission Line One of the key concerns in the transmission of electricity is the power loss in transmission lines, dissipated as heat due to the resistance of the conductors.High-voltage transmission lines are used to transmit electric power over long distances. Normally, high voltage (HV) transmission power lines are made of high voltage (between 138 and 765 kilovolts) conducting lines of copper and/or aluminum.Assume the power to be transmitted is P, and the resistance of the transmission line is r.If the power is transmitted with voltage V, then the current flow through the transmission line is I=P/V.The power loss Ploss=I2*r=(P/V)2*rSince P and r are fixed conditions, less power will be lost if high voltages V are used.Some students will raise questions like: From Ohm's law. if the voltage is increased, the current will increase ,too. Why is the current smaller when high voltage is used to transmit the power.Textbooks forgot to tell students that the transmission line needs a transformer to step down the voltage.And the transformer does not have a fixed impedance. If higher voltage is used to transmit the power, the ratio of the transformer will also change which will change the impedance of the transformer.The following applet was developed to help you understand the high power transmission line.

You can change the Power/Voltage V and resistance r in the transmission line with sliders.I will show current flow through the transmission line.Z is the total impedance of the transmission line, Zt is the impedance of the transformer.N:n shows the ratio of the high voltage transformer (Assume user voltage is 100V).Efficiency of the power line is also shown at the right side.

High voltage

Electricity Generation (duplicate)

Hydropower :A nonpolluting renewable energy source, hydroelectricity accounts for 20% of the electricity consumed around the world.

Electricity Generation : Source of Energy : Hydro Energy

Use of Hydro energy in Electricity Generation

Reservoir

Cross section

of Turbine

Electrical System : Sources of Energy

Use of Nuclear Energy in Electricity generation

Electricity Generation : Source of Energy : Nuclear Energy

High voltage

High voltage Direct Current

A high-voltage, direct current (HVDC) electric power transmission system uses direct current for the bulk transmission of electrical power, in contrast with the more common alternating current systems.[1] For long-distance transmission, HVDC systems may be less expensive and suffer lower electrical losses. For underwater power cables, HVDC avoids the heavy currents required to charge and discharge the cable capacitance each cycle. For shorter distances, the higher cost of DC conversion equipment compared to an AC system may still be warranted, due to other benefits of direct current links.HVDC allows power transmission between unsynchronized AC distribution

systems, and can increase system stability by preventing cascading failures due to phase instability from propagating from one part of a wider power transmission grid to another. HVDC also allows transfer of power between grid systems running at different frequences, such as 50 Hz vs. 60 Hz. Such interconnections improve the stability of each grid, since they increase the opportunity for any grid experiencing unusual loads to stay in service by drawing extra power from otherwise completely incompatible grids.

High voltage Direct Current (HVDC)

Finally, depending upon the environmental conditions and the performance of overhead line insulation operating with HVDC, it may be possible for a given transmission line to operate with a constant HVDC voltage that is approximately the same as the peak AC voltage for which it is designed and insulated. The power delivered in an AC system is defined by the root mean square (RMS) of an AC voltage, but RMS is only about 71% of the peak voltage. Therefore, if the HVDC line can operate continuously with an HVDC voltage that is the same as the peak voltage of the AC equivalent line, then for a given current (where HVDC current is the same as the RMS current in the AC line), the power transmission capability when operating with HVDC is approximately 140% of the capability when operating with AC. Overhead Transmission lines

High voltage Direct Current (HVDC)

The modern form of HVDC transmission uses technology developed extensively in the 1930s in Sweden (ASEA) and in Germany .Early commercial installations included one in the Soviet Union in 1951 between Moscow and Kashira, and a 100 kV, 20 MW system between Gotland and mainland Sweden in 1954.

The longest HVDC link in the world is currently the Xiangjiaba–Shanghai 2,071 km (1,287 mi), ±800 kV, 6400 MW link connecting the Xiangjiaba Dam to Shanghai, in the

' People s Republic of China.In 2012, the longest HVDC link will be the Rio Madeira link in Brazil, which consists of two bipoles of ±600 kV, 3150 MW each, connecting Porto Velho in the state of Rondônia to the São Paulo area, where the length of the DC line is over 2,500 km (1,600 mi).

Long distance HVDC lines carrying hydroelectricity from Canada's Nelson river to this converter station where it is converted to AC for use in Winnipeg's local grid

High voltage

HIGH VOLTAGE MULTIPLIERSHigh Voltage MultipliersHigh Voltage Multipliers are utilized in a number of applications including X-Ray high voltage power supplies, electrostatic paint spray applications, TWT amplifiers, and CRTs. Multipliers are typically specific to particular applications .

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