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Diesel Generators
A diesel generator (DG) (also known as a diesel Genset) is the combination of a diesel engine with an electric generator (often an alternator) to generate electrical energy. This is a specific case of engine generator. A diesel compression-ignition engine is usually designed to run on diesel fuel, but some types are adapted for other liquid fuels or natural gas. Diesel generating sets are used in places without connection to a power grid, or as an emergency power supply if the grid fails, as well as for more complex applications such as peak-lopping, grid support, and export to the power grid. Diesel generator size is crucial to minimize low load or power shortages. Sizing is complicated by the characteristics of modern electronics, specifically non-linear loads. In size ranges around 50 MW and above, an open cycle gas turbine is more efficient at full load than an array of diesel engines, and far more compact, with comparable capital costs; but for regular part-loading, ev ...
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Power Station
A power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Power stations are generally connected to an electrical grid. Many power stations contain one or more generators, a rotating machine that converts mechanical power into three-phase electric power. The relative motion between a magnetic field and a conductor creates an electric current. The energy source harnessed to turn the generator varies widely. Most power stations in the world burn fossil fuels such as coal, oil, and natural gas to generate electricity. Low-carbon power sources include nuclear power, and an increasing use of renewables such as solar, wind, geothermal, and hydroelectric. History In early 1871 Belgian inventor Zénobe Gramme invented a generator powerful enough to produce power on a commercial scale for industry. In 1878, a hydroelectric power station was designed and built b ...
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Displacement Power Factor
In electrical engineering, the power factor of an AC power system is defined as the ratio of the ''real power'' absorbed by the load to the ''apparent power'' flowing in the circuit. Real power is the average of the instantaneous product of voltage and current and represents the capacity of the electricity for performing work. Apparent power is the product of RMS current and voltage. Due to energy stored in the load and returned to the source, or due to a non-linear load that distorts the wave shape of the current drawn from the source, the apparent power may be greater than the real power, so more current flows in the circuit than would be required to transfer real power alone. A power factor magnitude of less than one indicates the voltage and current are not in phase, reducing the average product of the two. A negative power factor occurs when the device (which is normally the load) generates real power, which then flows back towards the source. In an electric power system, ...
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Harmonics (electrical Power)
In an electric power system, a harmonic of a voltage or current waveform is a sinusoidal wave whose frequency is an integer multiple of the fundamental frequency. Harmonic frequencies are produced by the action of non-linear loads such as rectifiers, discharge lighting, or saturated electric machines. They are a frequent cause of power quality problems and can result in increased equipment and conductor heating, misfiring in variable speed drives, and torque pulsations in motors and generators. Harmonics are usually classified by two different criteria: the type of signal (voltage or current), and the order of the harmonic (even, odd, triplen, or non-triplen odd); in a three-phase system, they can be further classified according to their phase sequence (positive, negative, zero). Current harmonics In a normal alternating current power system, the current varies sinusoidally at a specific frequency, usually 50 or 60 hertz. When a linear time-invariant electrical load is connected ...
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Volt-ampere Reactive
A volt-ampere ( SI symbol: V⋅A or V A, simplified as VA) is the unit for the apparent power in an electrical circuit. The apparent power equals the product of root mean square voltage (in volts) and root mean square current (in amperes). Volt-amperes are usually used for analyzing alternating current (AC) circuits. In direct current (DC) circuits, this product is equal to the real power, in watts. The volt-ampere is dimensionally equivalent to the watt: in SI units, 1 V⋅A = 1 W). VA rating is most used for generators and transformers (and other power handling equipment) where loads may be reactive (inductive or capacitive). Formulation For a simple electrical circuit running on direct current, the electrical current and voltage are constant. In that case, the real power (''P'', measured in watts) is the product of the electrical current (''I'', measured in amperes) and the voltage from one side of the circuit to the other (''V'', measured in volts): ...
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Volt-ampere
A volt-ampere ( SI symbol: V⋅A or V A, simplified as VA) is the unit for the apparent power in an electrical circuit. The apparent power equals the product of root mean square voltage (in volts) and root mean square current (in amperes). Volt-amperes are usually used for analyzing alternating current (AC) circuits. In direct current (DC) circuits, this product is equal to the real power, in watts. The volt-ampere is dimensionally equivalent to the watt: in SI units, 1 V⋅A = 1 W). VA rating is most used for generators and transformers (and other power handling equipment) where loads may be reactive (inductive or capacitive). Formulation For a simple electrical circuit running on direct current, the electrical current and voltage are constant. In that case, the real power (''P'', measured in watts) is the product of the electrical current (''I'', measured in amperes) and the voltage from one side of the circuit to the other (''V'', measured in volts): ...
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Kilowatt
The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Watt (1736–1819), an 18th-century Scottish inventor, mechanical engineer, and chemist who improved the Newcomen engine with his own steam engine in 1776. Watt's invention was fundamental for the Industrial Revolution. Overview When an object's velocity is held constant at one metre per second against a constant opposing force of one newton, the rate at which work is done is one watt. : \mathrm In terms of electromagnetism, one watt is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the volt-ampere (the latter unit, however, is used for a different quantity from the real power of an electrical circuit). : ...
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Electrical Load
An electrical load is an electrical component or portion of a circuit that consumes (active) electric power, such as electrical appliances and lights inside the home. The term may also refer to the power consumed by a circuit. This is opposed to a power source, such as a battery or generator, which ''produces'' power. The term is used more broadly in electronics for a device connected to a signal source, whether or not it consumes power. If an electric circuit has an output port, a pair of terminals that produces an electrical signal, the circuit connected to this terminal (or its input impedance) is the ''load''. For example, if a CD player is connected to an amplifier, the CD player is the source and the amplifier is the load. Load affects the performance of circuits with respect to output voltages or currents, such as in sensors, voltage sources, and amplifiers. Mains power outlets provide an easy example: they supply power at constant voltage, with electrical applianc ...
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Locomotive
A locomotive or engine is a rail transport vehicle that provides the Power (physics), motive power for a train. If a locomotive is capable of carrying a payload, it is usually rather referred to as a multiple unit, Motor coach (rail), motor coach, railcar or power car; the use of these self-propelled vehicles is increasingly common for passenger trains, but rare for freight (see CargoSprinter). Traditionally, locomotives pulled trains from the front. However, Push-pull train, push-pull operation has become common, where the train may have a locomotive (or locomotives) at the front, at the rear, or at each end. Most recently railroads have begun adopting DPU or distributed power. The front may have one or two locomotives followed by a mid-train locomotive that is controlled remotely from the lead unit. __TOC__ Etymology The word ''locomotive'' originates from the Latin language, Latin 'from a place', Ablative case, ablative of 'place', and the Medieval Latin 'causing mot ...
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Rail Transport
Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a prepared flat surface, rail vehicles ( rolling stock) are directionally guided by the tracks on which they run. Tracks usually consist of steel rails, installed on sleepers (ties) set in ballast, on which the rolling stock, usually fitted with metal wheels, moves. Other variations are also possible, such as "slab track", in which the rails are fastened to a concrete foundation resting on a prepared subsurface. Rolling stock in a rail transport system generally encounters lower frictional resistance than rubber-tyred road vehicles, so passenger and freight cars (carriages and wagons) can be coupled into longer trains. The operation is carried out by a railway company, providing transport between train stations or freight customer ...
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World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ...
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