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Rheostatic Brake
Dynamic braking is the use of an electric traction motor as a generator when slowing a vehicle such as an electric or diesel-electric locomotive. It is termed " rheostatic" if the generated electrical power is dissipated as heat in brake grid resistors, and " regenerative" if the power is returned to the supply line. Dynamic braking reduces wear on friction-based braking components, and regeneration lowers net energy consumption. Dynamic braking may also be used on railcars with multiple units, light rail vehicles, electric trams, trolleybuses, and electric and hybrid electric automobiles. Principle of operation Converting electrical energy to the mechanical energy of a rotating shaft (electric motor) is the inverse of converting the mechanical energy of a rotating shaft to electrical energy (electric generator). Both are accomplished through the interactions of armature windings with a (relatively) moving external magnetic field, with the armature connected to an electrical c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Energy
Electrical energy is the energy transferred as electric charges move between points with different electric potential, that is, as they move across a voltage, potential difference. As electric potential is lost or gained, work is done changing the energy of some system. The amount of work in Joule, joules is given by the product of the charge that has moved, in Coulomb, coulombs, and the potential difference that has been crossed, in Volt, volts. Electrical energy is usually sold by the kilowatt hour (1 kW·h = 3.6 MJ) which is the product of the power in kilowatts multiplied by running time in hours. Electric utilities measure energy using an electricity meter, which keeps a running total of the electrical energy delivered to a customer. Electric heating is an example of converting electrical energy into thermal energy. The simplest and most common type of electric heater uses electrical resistance to convert the energy. There are other ways to use electrical energy. Electri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inverter (electrical)
A power inverter, inverter, or invertor is a power electronic device or circuitry that changes direct current (DC) to alternating current (AC). The resulting AC frequency obtained depends on the particular device employed. Inverters do the opposite of rectifiers which were originally large electromechanical devices converting AC to DC. The input voltage, output voltage and frequency, and overall power handling depend on the design of the specific device or circuitry. The inverter does not produce any power; the power is provided by the DC source. A power inverter can be entirely electronic or maybe a combination of mechanical effects (such as a rotary apparatus) and electronic circuitry. Static inverters do not use moving parts in the conversion process. Power inverters are primarily used in electrical power applications where high currents and voltages are present; circuits that perform the same function for electronic signals, which usually have very low currents and vol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Union Pacific Railroad
The Union Pacific Railroad is a Railroad classes, Class I freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Pacific is the second largest railroad in the United States after BNSF Railway, BNSF, with which it shares a duopoly on transcontinental freight rail lines in the Western United States, Western, Midwestern United States, Midwestern and West South Central states, West South Central United States. Founded in 1862, the original Union Pacific Rail Road was part of the first transcontinental railroad project, later known as the Overland Route (Union Pacific Railroad), Overland Route. Over the next century, UP absorbed the Missouri Pacific Railroad, the Western Pacific Railroad, the Missouri–Kansas–Texas Railroad and the Chicago, Rock Island and Pacific Railroad. In 1995, the Union Pacific merged with Chicago and North Western Transportation Company, completing its reach into the Upper Midwest. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kansas City Southern Railway
The Kansas City Southern Railway Company is an American Class I railroad. Founded in 1887, it operated in 10 Midwestern United States, Midwestern and Southeastern United States, Southeastern U.S. states: Illinois, Missouri, Kansas, Oklahoma, Arkansas, Tennessee, Alabama, Mississippi, Louisiana and Texas. KCS owned the shortest north-south rail route between Kansas City, Missouri, and several key ports along the Gulf of Mexico. The focus of the routes was the fastest way to connect Kansas City to seaports, since it was only 800 miles from Kansas City to the Gulf of Mexico compared to 1,400 miles between Kansas City and the Atlantic Ocean ports. KCS operated over a railroad system consisting of that extended south to the Mexico–United States border at which point another KCS-operated railroad, Kansas City Southern de México (KCSM), hauled freight into northeastern and central Mexico and to several Gulf of Mexico ports and the Pacific Port of Lázaro Cárdenas. Canadian Pacifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BNSF Railway
BNSF Railway is the largest freight railroad in the United States. One of six North American Class I railroads, BNSF has 36,000 employees, of track in 28 states, and over 8,000 locomotives. It has three Transcontinental railroad, transcontinental routes that provide rail connections between the western and eastern United States. BNSF trains traveled over in 2010, more than any other North American railroad. The BNSF Railway Company is the principal operating subsidiary of parent company Burlington Northern Santa Fe, LLC. Headquartered in Fort Worth, Texas, the railroad's parent company is a wholly owned subsidiary of Berkshire Hathaway Inc., of Omaha, Nebraska. The current CEO is Kathryn Farmer. According to corporate press releases, BNSF Railway is among the top transporters of intermodal freight in North America. It also hauls bulk cargo, including coal. The creation of BNSF started with the formation of a holding company on September 22, 1995. This new holding compa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian Pacific Railway
The Canadian Pacific Railway () , also known simply as CPR or Canadian Pacific and formerly as CP Rail (1968–1996), is a Canadian Class I railway incorporated in 1881. The railway is owned by Canadian Pacific Kansas City, Canadian Pacific Kansas City Limited, known until 2023 as Canadian Pacific Railway Limited, which began operations as legal owner in a corporate restructuring in 2001. The railway is headquartered in Calgary, Alberta. In 2023, the railway owned approximately of track in seven provinces of Canada and into the United States, stretching from Montreal to Vancouver, and as far north as Edmonton. Its rail network also served Minneapolis–St. Paul, Milwaukee, Detroit, Chicago, and Albany, New York, in the United States. The railway was first built between eastern Canada and British Columbia between 1875 and 1885 (connecting with Ottawa Valley and Georgian Bay area lines built earlier), fulfilling a commitment extended to British Columbia when it entered Canadia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Goat
Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 nm. In subtractive color systems, used in painting and color printing, it is created by a combination of yellow and cyan; in the RGB color model, used on television and computer screens, it is one of the additive primary colors, along with red and blue, which are mixed in different combinations to create all other colors. By far the largest contributor to green in nature is chlorophyll, the chemical by which plants photosynthesize and convert sunlight into chemical energy. Many creatures have adapted to their green environments by taking on a green hue themselves as camouflage. Several minerals have a green color, including the emerald, which is colored green by its chromium content. During post-classical and early modern Europe, green was the color commonly associated with wealth, merchants, bankers, and the gentry, while red was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regenerative Braking
Regenerative braking is an energy recovery mechanism that slows down a moving vehicle or object by converting its kinetic energy or potential energy into a form that can be either used immediately or stored until needed. Typically, regenerative brakes work by driving an electric motor in reverse to recapture energy that would otherwise be lost as heat during braking, effectively turning the traction motor into a generator. Feeding power backwards through the system like this allows the energy harvested from deceleration to resupply an energy storage solution such as a battery or a capacitor. Once stored, this power can then be later used to aid forward propulsion. Because of the electrified vehicle architecture required for such a braking system, automotive regenerative brakes are most commonly found on hybrid and electric vehicles. This method contrasts with conventional braking systems, where excess kinetic energy is converted to unwanted and wasted heat due to friction i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Electrification System
Railway electrification is the use of electric power for the propulsion of rail transport. Electric railways use either electric locomotives (hauling passengers or freight in separate cars), electric multiple units ( passenger cars with their own motors) or both. Electricity is typically generated in large and relatively efficient generating stations, transmitted to the railway network and distributed to the trains. Some electric railways have their own dedicated generating stations and transmission lines, but most purchase power from an electric utility. The railway usually provides its own distribution lines, switches, and transformers. Power is supplied to moving trains with a (nearly) continuous conductor running along the track that usually takes one of two forms: an overhead line, suspended from poles or towers along the track or from structure or tunnel ceilings and contacted by a pantograph, or a third rail mounted at track level and contacted by a sliding " pickup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brake
A brake is a machine, mechanical device that inhibits motion by absorbing energy from a moving system. It is used for Acceleration, slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. Background Most brakes commonly use friction between two surfaces pressed together to convert the kinetic energy of the moving object into heat, though other methods of energy conversion may be employed. For example, regenerative braking converts much of the energy to electrical energy, which may be stored for later use. Other methods convert kinetic energy into potential energy in such stored forms as Compressed air energy storage, pressurized air or pressurized oil. Eddy current brakes use magnetic fields to convert kinetic energy into electric current in the brake disc, fin, or rail, which is converted into heat. Still other braking methods even transform kinetic energy into different forms, for example by transferring the en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Excitation (magnetic)
In electromagnetism, excitation is the process of generating a magnetic field by means of an electric current. An electric generator or electric motor consists of a rotor spinning in a magnetic field. The magnetic field may be produced by permanent magnets or by field coils. In the case of a machine with field coils, a current must flow in the coils to generate (''excite'') the field, otherwise no power is transferred to or from the rotor. Field coils yield the most flexible form of magnetic flux regulation and de-regulation, but at the expense of a flow of electric current. Hybrid topologies exist, which incorporate both permanent magnets and field coils in the same configuration. The flexible excitation of a rotating electrical machine is employed by either brushless excitation techniques or by the injection of current by carbon brushes (static excitation). Excitation in generators For a machine using field coils, as is the case in most large generators, the fie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
