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HVDC
A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems. Most HVDC links use voltages between 100 kV and 800 kV. HVDC lines are commonly used for long-distance power transmission, since they require fewer conductors and incur less power loss than equivalent AC lines. HVDC also allows power transmission between AC transmission systems that are not Synchronization (alternating current), synchronized. Since the power flow through an HVDC link can be controlled independently of the phase angle between source and load, it can stabilize a network against disturbances due to rapid changes in power. HVDC also allows the transfer of power between grid systems running at different frequencies, such as 50 and 60 Hz. This improves the stability and economy of each grid, by allowing the exchange of power between previously inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury-arc Valve
A mercury-arc valve or mercury-vapor rectifier or (UK) mercury-arc rectifier is a type of electrical rectifier used for converting high-voltage or high- current alternating current (AC) into direct current (DC). It is a type of cold cathode gas-filled tube, but is unusual in that the cathode, instead of being solid, is made from a pool of liquid mercury and is therefore self-restoring. As a result mercury-arc valves, when used as intended, are far more robust and durable and can carry much higher currents than most other types of gas discharge tube. Some examples have been in continuous service, rectifying 50-ampere currents, for decades. Invented in 1902 by Peter Cooper Hewitt, mercury-arc rectifiers were used to provide power for industrial motors, electric railways, streetcars, and electric locomotives, as well as for radio transmitters and for high-voltage direct current (HVDC) power transmission. They were the primary method of high power rectification before the advent o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Power Transmission
Electric power transmission is the bulk movement of electrical energy from a generating site, such as a power plant, to an electrical substation. The interconnected lines that facilitate this movement form a ''transmission network''. This is distinct from the local wiring between high-voltage substations and customers, which is typically referred to as electric power distribution. The combined transmission and distribution network is part of electricity delivery, known as the electrical grid. Efficient long-distance transmission of electric power requires high voltages. This reduces the losses produced by strong currents. Transmission lines use either alternating current (AC) or direct current (DC). The voltage level is changed with transformers. The voltage is stepped up for transmission, then reduced for local distribution. A wide area synchronous grid, known as an ''interconnection'' in North America, directly connects generators delivering AC power with the same rela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyristor
A thyristor (, from a combination of Greek language ''θύρα'', meaning "door" or "valve", and ''transistor'' ) is a solid-state semiconductor device which can be thought of as being a highly robust and switchable diode, allowing the passage of current in one direction but not the other, often under control of a gate electrode, that is used in high power applications like inverters and radar generators. It usually consists of four layers of alternating P- and N-type materials. It acts as a bistable switch (or a latch). There are two designs, differing in what triggers the conducting state. In a three-lead thyristor, a small current on its gate lead controls the larger current of the anode-to-cathode path. In a two-lead thyristor, conduction begins when the potential difference between the anode and cathode themselves is sufficiently large (breakdown voltage). The thyristor continues conducting until the voltage across the device is reverse-biased or the voltage is removed (b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power Electronics
Power electronics is the application of electronics to the control and conversion of electric power. The first high-power electronic devices were made using mercury-arc valves. In modern systems, the conversion is performed with semiconductor switching devices such as diodes, thyristors, and power transistors such as the power MOSFET and IGBT. In contrast to electronic systems concerned with the transmission and processing of signals and data, substantial amounts of electrical energy are processed in power electronics. An AC/DC converter (rectifier) is the most typical power electronics device found in many consumer electronic devices, e.g. television sets, personal computers, battery chargers, etc. The power range is typically from tens of watts to several hundred watts. In industry, a common application is the Adjustable-speed drive, variable speed drive (VSD) that is used to control an induction motor. The power range of VSDs starts from a few hundred watts and ends at ten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kashira
Kashira () is a types of inhabited localities in Russia, town and the administrative center of Kashirsky District, Moscow Oblast, Kashirsky District in Moscow Oblast, located on the Oka River south of Moscow. Population: History It was first mentioned in 1356 as the village of Koshira () named after the Koshira River (today's Kashirka River). However, 1619 is considered Kashira's foundation year, when the town was transferred from the left bank of the Oka to the right bank some upstream and rebuilt after it was badly damaged by the Crimean Tatars in 1592 and 1596. The town was once home to exiled Khanate of Kazan, Kazan Khan Ghabdellatif of Kazan, Ghabdellatif. The coat of arms of Kashira contains the image of Zilant, a heraldic symbol of Kazan. Town status was granted to Kashira in 1777. Kashira's southern suburbs were entered in by Germany on 24 November to 17 December 1941 and was a massacre site of Poles and Jews relating to the Katyn massacre. It is reported that, dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct Current
Direct current (DC) is one-directional electric current, flow of electric charge. An electrochemical cell is a prime example of DC power. Direct current may flow through a conductor (material), conductor such as a wire, but can also flow through semiconductors, electrical insulation, insulators, or even through a vacuum as in electron beam, electron or ion beams. The electric current flows in a constant direction, distinguishing it from alternating current (AC). A archaism, term formerly used for this type of current was galvanic current. The abbreviations ''AC'' and ''DC'' are often used to mean simply ''alternating'' and ''direct'', as when they modify ''Electric current, current'' or ''voltage''. Direct current may be converted from an alternating current supply by use of a rectifier, which contains Electronics, electronic elements (usually) or electromechanical elements (historically) that allow current to flow only in one direction. Direct current may be converted into alt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
René Thury
René Thury (7 August 1860 – 23 April 1938) was a Switzerland, Swiss pioneer in electrical engineering. He was known for his work with high voltage direct current electricity transmission and was known in the professional world as the "King of DC." Biography René Thury's father, Marc-Antoine Thury, was a teacher of Natural History. From 1874 René became an apprentice at Société Instruments Physiques, a precision machine building firm in Geneva working for Emil Bürgin who made refinements to the gramme machine, dynamos of Zénobe Gramme. When Bürgin left SIP in 1876, Thury became his successor. He was also served as a laboratory technician of Prof. Jacques-Louis Soret at the University of Geneva. Soret had acquired a Burgin dynamo placing it in series with batteries, and Thury secretly devised a means to make the batteries superfluous. In 1877, he built a steam powered tricycle along with a medical student Jean-Jacques Nussberger who financed the project. It could re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allmänna Svenska Elektriska Aktiebolaget
''Allmänna Svenska Elektriska Aktiebolaget'' ( English translation: General Swedish Electrical Limited Company; Swedish abbreviation: ASEA) was a Swedish industrial company. History ASEA was founded in 1883 by Ludvig Fredholm in Västerås as a manufacturer of electrical light and generators. After merging with Wenström's & Granström's Electrical Power Company (''Wenströms & Granströms Elektriska Kraftbolag'') the name was changed to ''Allmänna Svenska Elektriska Aktiebolaget'', literally the "General Swedish Electrical Limited Company", or ''ASEA'' for short. In 1987, it announced a merger with the Swiss company Brown, Boveri & Cie (BBC) to form ABB. The merge took effect on 1 January 1988.ASEA-BBC merger '' Modern Railways'' issue 472 January 1988 page 34 After this merger, ABB acquired several companies, including the power transmission and distribution operations of the Westinghouse Electric Corporation and the Combustion Engineering Group. *1889 – the partner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thury HVDC System
Thury may refer to: People * Pierre de Thury ( -1410), said the cardinal Maillezais, a French cardinal of the Avignon Obedience, see Council of Pisa *György Thury (1519-1571), a Hungarian nobleman ( hu) *Louis-Pierre Thury (died in 1699), French missionary priest in Acadia * César-François Cassini de Thury (1714-1784), French geographer * Louis-Étienne Héricart de Thury (1776–1854), French scientist and politician *René Thury René Thury (7 August 1860 – 23 April 1938) was a Switzerland, Swiss pioneer in electrical engineering. He was known for his work with high voltage direct current electricity transmission and was known in the professional world as the "Kin ... (1860-1938), a Swiss engineer Toponyms France * Thury, Côte-d'Or, in the Côte-d'Or (département) * Thury, Yonne, in the Yonne (département) * Thury-en-Valois, in the Oise (département) * Thury-Harcourt, in the Calvados (département) * Thury-sous-Clermont, in the Oise (département) * La Villeneu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gotland
Gotland (; ; ''Gutland'' in Gutnish), also historically spelled Gottland or Gothland (), is Sweden's largest island. It is also a Provinces of Sweden, province/Counties of Sweden, county (Swedish län), Municipalities of Sweden, municipality, and List of dioceses, deaneries and parishes of the Church of Sweden, diocese. The province includes the islands of Fårö and Gotska Sandön to the north, as well as the Karlsö Islands (Lilla Karlsö, Lilla and Stora Karlsö, Stora) to the west. The population is 61,023 (2024) of which about 23,600 live in Visby, the main town. Outside Visby, there are minor settlements and a mainly rural population. The island of Gotland and the other areas of the province of Gotland make up less than one percent of Sweden's total land area. The county formed by the archipelago is the second smallest by area and is the least populated in Sweden. In spite of the small size due to its narrow width, the driving distance between the furthermost points of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after India, representing 17.4% of the world population. China spans the equivalent of five time zones and Borders of China, borders fourteen countries by land across an area of nearly , making it the list of countries and dependencies by area, third-largest country by land area. The country is divided into 33 Province-level divisions of China, province-level divisions: 22 provinces of China, provinces, 5 autonomous regions of China, autonomous regions, 4 direct-administered municipalities of China, municipalities, and 2 semi-autonomous special administrative regions. Beijing is the country's capital, while Shanghai is List of cities in China by population, its most populous city by urban area and largest financial center. Considered one of six ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
