SU788181A1

SU788181A1 - Ac lead

Info

Publication number: SU788181A1
Application number: SU792726852A
Authority: SU
Inventors: Александр Владимирович Карпачев; Владимир Степанович Околотин
Original assignee: Государственный Научно-Исследовательский Энергетический Институт Им. Г.М. Кржижановского
Priority date: 1979-02-19
Filing date: 1979-02-19
Publication date: 1980-12-15

Description

Изобретение относится к электротехнике и может быть использовано в токопроводах переменного тока с произвольным числом фазных проводников для снижения реактивных потерь тока ’ и напряжения.The invention relates to electrical engineering and can be used in AC current conductors with an arbitrary number of phase conductors to reduce reactive current losses ’and voltage.

Известен токопровод, в котором для снижения электрических потерь каждый фазный проводник выполняется из 2-х коаксиальных проводников, обтекаемых рабочими токами в противофазе [1] .Known conductors, in which to reduce electrical losses, each phase conductor is made of 2 coaxial conductors, streamlined by operating currents in antiphase [1].

Недостатком этого токопровода является повышенный расход проводникового материала из расчета передачи 15 полного тока, а также усложнение, электрической схемы и коммутации цепи из-за наличия 4-х концов каждой фазы.The disadvantage of this conductor is the increased consumption of conductive material from the calculation of the transfer of 15 full current, as well as the complication of the electrical circuit and switching circuits due to the presence of 4 ends of each phase.

Наиболее близким к изобретению является токопровод, содержащий фаз- 20 ные проводники с электромагнитными экранами, которые связаны по концам перемычками в короткозамкнутый контур, а на перемычках размещены трансформаторы для регулирования тока в 25 экране pQ .Closest to the invention is a current conductor comprising phase 20 conductors with electromagnetic shields, which are connected at the ends by jumpers into a short-circuited circuit, and transformers for controlling current in the 25th pQ screen are placed on the jumpers.

Недостатком этого устройства является неравенство токов в проводнике и экране по фазе и напряжению изза конечного импеданса для токов эк- 30 • 2 рана, что ограничивает снижение индуктивности основного контура и потерь реактивной мощности. Кроме того, величина тока контролируется в двух из трех межфазных экранных перемычках, что затрудняет определение токов в каждом фазном экране.The disadvantage of this device is the inequality of the currents in the conductor and the shield in phase and voltage due to the final impedance for currents of 30–2 wounds, which limits the decrease in the inductance of the main circuit and the loss of reactive power. In addition, the current value is controlled in two of the three interphase screen jumpers, which makes it difficult to determine the currents in each phase screen.

Цель изобретения - повышение экономичности путем снижения потерь реактивной мощности.The purpose of the invention is to increase efficiency by reducing reactive power losses.

Поставленная цель достигается тем, что трансформаторы размещены на электромагнитных экранах каждой фазы, которые являются первичной обмоткой, а вторичные обмотки трансформаторов присоединены к источнику с регулируемым выходным напряжением.This goal is achieved in that the transformers are placed on the electromagnetic screens of each phase, which are the primary winding, and the secondary windings of the transformers are connected to a source with an adjustable output voltage.

На фиг. 1 изображена в трехфазном исполнении электрическая схема токопровода; на фиг. 2 - в однофазном исполнении схема замещения; на фиг. 3векторная диаграмма токов и напряжений .In FIG. 1 shows a three-phase design of an electrical circuit of a current lead; in FIG. 2 - in a single-phase execution equivalent circuit; in FIG. 3-vector diagram of currents and voltages.

Токопровод содержит фазные проводники 1, экраны 2, перемычки 3, связывающие экраны 2 в короткозамкнутый контур, трансформаторы 4, расположенные на экранах, которые служат одной обмоткой трансформаторов, регулируемый источник 5, присоединенный к другой обмотке трансформаторов. Экраны 2 могут иметь различное конструктивное выполнение (трубчатые шины, плоские шины, пакет правильных проводников), однако они должны быть вы-’ полнены из металла и расположены с наименьшим зазором от фазных проводников по требованиям электрической прочности изоляции, технологическим ограничениям, условия охлаждения И Т. Π .The current lead contains phase conductors 1, shields 2, jumpers 3, connecting shields 2 into a short-circuited circuit, transformers 4 located on the shields that serve as one winding of transformers, an adjustable source 5 connected to another winding of transformers. Screens 2 can have various designs (tubular tires, flat tires, a package of straight conductors), however, they must be made of metal and located with the smallest gap from the phase conductors according to the requirements of electrical insulation strength, technological limitations, cooling conditions, and T . Π.

Токопровод работает следующим об, разом.The conductor operates as follows.

Протекание фазного тока 1<р имеет следствием потери напряжения Αϋψ на активном сопротивлении R<p и сопротивлении самоиндукции L<p. Потери напряжения в экране ди_я складываются из потерь на сопротивлениях экрана R₃и· L₃. Протекание в экране тока 1₃обеспечивается за счет ЭДС взаимоиндукции ΙφωΜ и ЭДС источника U. Наличие короткозамкнутого контура с током обеспечивает электромагнитное наведение в фазовом проводнике 1 ЭДС взаимоиндукции , с учетом которой итоговые потери напряжения в проводнике 1 изменяются отди^ до SU<p.The flow of phase current 1 <p results in a voltage loss Αϋψ on the active resistance R <p and self-induction resistance L <p. Voltage losses in the di _I consist of losses ₃ and R · L ₃ screen resistances. The flow of current 1 ₃ in the screen is ensured by the mutual induction EMF Ιφω Э and the EMF of the source U. The presence of a short-circuited circuit with the current provides electromagnetic guidance in the phase conductor 1 of the mutual induction EMF, taking into account which the total voltage loss in conductor 1 changes from ^ to SU <p.

На фиг. 3 представлена векторная диаграмма токов и напряжений в схеме на фиг. 2 для частного случая, когда токи Ιφ и 1_э равны по величине и направлены встречно. При этом потребление реактивной мощности в проводнике 1 определяется магнитным потоком между проводниками 1 и 2, а источник U выбирается из условия компенсации этой реактивной мощности и потерь активной мощности в короткозамкнутом контуре. В общем случае можно изменять вектор тока и напряжения источника 5 таким образом, чтобы вырабатываемая им реактивная мощность имела по отношению к фазному проводнику 1 как емкостной, так и индуктивный Характер. По этой причине предлагаемый токопровод переменного то. ка выполняет функции управляемого ’ источника реактивной мощности в линии.In FIG. 3 is a vector diagram of currents and voltages in the circuit of FIG. 2 for the special case when the currents Ιφ and 1 _ee are equal in magnitude and are directed counter-to. In this case, the reactive power consumption in conductor 1 is determined by the magnetic flux between conductors 1 and 2, and the source U is selected from the condition for compensation of this reactive power and active power losses in the short-circuited circuit. In the general case, the current and voltage vector of source 5 can be changed so that the reactive power generated by it has both capacitive and inductive Character with respect to phase conductor 1. For this reason, the proposed alternating current conductor is then. It acts as a controlled 'source of reactive power in the line.

Предложенный токопровод обеспечивает разгрузку основной цепи от реактивных токов, разгрузку источников основной цепи от выработки реактивной мощности, соответствующий рост передаваемых по линии активных токов и мощности.The proposed current lead provides unloading of the main circuit from reactive currents, unloading the sources of the main circuit from the generation of reactive power, a corresponding increase in the active currents and power transmitted through the line.

Claims

(54) AC CURRENT CURRENT The invention relates to electrical engineering and can be used in AC conductors with an arbitrary number of phase conductors to reduce reactive current losses and voltages. A conductor is known in which, in order to reduce electrical losses, each phase conductor is made of 2 coaxial conductors flowing around the working currents in antiphase i. The disadvantage of this conductor is the increased consumption of conductor material based on the transfer of total current, as well as the complication of the electrical circuit and circuit switching due to the presence of 4 ends of each phase. The conductor containing phase conductors with electromagnetic shields is closest to the invention. which are connected at the ends by jumpers to a short-circuited circuit, and on the jumpers are placed transformers for regulating the current in screen 2. The disadvantage of this device is the inequality of the currents in the conductor and the screen in phase and voltage due to the final impedance for the screen currents, which limits the decrease in inductance of the main circuit and the loss of reactive power. In addition, the magnitude of the current is controlled in two of the three interphase screen bridges, which makes it difficult to determine the currents in each phase screen. The purpose of the invention is to increase efficiency by reducing reactive power losses. The goal is achieved by the fact that the transformers are placed on the electromagnetic screens of each phase, which are the primary winding, and the secondary windings of the transformers are connected to a source with an adjustable output voltage. FIG. 1 shows a three-phase electrical conductor diagram; in fig. 2 - in the single-phase version; in fig. 3 vector diagram of currents and voltages. The conductor contains phase conductors 1, screens 2, jumpers 3, connecting screens 2 in a short-circuited circuit, transformers 4 located on screens that serve as one winding of transformers, adjustable source 5, is connected1. to another winding of transformers. Screens 2 may have different constructive design (tubular tires, (; glossy tires, package of correct conductors), however, they must be made of metal and located with the smallest gap from the phase conductors as required by electrical insulation strength, technological limitations , cooling conditions, etc. The conductor operates as follows: Immediately, the flow of the phase current Im results from the loss of voltage AUqj on the active resistance Rqj and the resistance of self-induction 1. Phase voltage losses in the screen uU are added from loss on the screen resistances Kz I-. Lg. The current flow in the screen l is provided by the emf of mutual inductance 1фО |) M and the emf of source U. The presence of a short-circuited circuit with current provides electromagnetic guidance in the phase conductor 1 of the emf of mutual induction 1fslm, which takes into account voltage losses in conductor 1 change from drift to. FIG. 3 is a vector diagram of currents and voltages in the circuit of FIG. 2 for the particular case when currents 1f and Ig are equal in magnitude and directed oppositely. In this case, the consumption of reactive power in conductor 1 is determined by the magnetic flux between conductors 1 and 2, and the source U is selected from the condition of compensation of this reactive power and loss of active power in a short-circuited loop. In the general case, it is possible to vary the current vector and the voltage of source 5 so that the reactive power generated by it has, in relation to phase conductor 1, both capacitive and inductive jtapaKTep. For this reason, the proposed AC conductor performs the functions of a controlled source of reactive power in a line. The proposed conductors provide unloading of the main circuit from reactive currents, unloading of the sources of the main circuit from the generation of reactive power, the corresponding growth of active currents and power transmitted along the line. Claims of alternating current, containing phase conductors with electromagnetic shields, closed interphase bridges, and transformers associated with the aforementioned shields, characterized in that, in order to improve efficiency by reducing reactive power losses, the current lead is supplied with an adjustable voltage source, transformers are placed on electromagnetic screens of each phase, with one of the transformer windings surrounded by a section of the screen, while others are connected to the output of the regulator voltage, Sources of information taken into account during the examination. 1. USSR author's certificate No. 140833, cl. H 01 B 5/00, 1961.

2. USSR Author's Certificate No. 510765, cl. H 01 B 5/00, 1970.

i

2