RU2273939C1 - Method and device for transferring electric energy (variants) - Google Patents

Abstract

FIELD: electric engineering, possible use for transferring electric energy.

SUBSTANCE: transferring of electric energy is performed below ground or below water in resonance mode at resonance frequency 50 Hz - 50 KHz and voltage 1-1000 kV, current density 1-500 A/mm² along one-wire electric-insulated cable, in particular, multi-wired, with length 1-20000 km with section 0,01-1000 cm², cable diameter of which exceeds wire diameter in 5-100 times. In accordance to another variant electric energy is transferred below ground or below water in resonance mode along axial-symmetric one-wire wave duct inside hermetic hollow dielectric cylinder-shaped channel in insulating gas atmosphere, in particular, electronic gas under pressure 1-10 kg/cm². In accordance to yet another variant of method electric energy is transferred along single electro-statically screened and electric-insulated wave duct of surface wave inside the hollow-bodied cylinder-shaped screen and hermetic dielectric channel in atmosphere of insulated gas. High-voltage line may be made below ground or below water in form of one-conductor wave guide with length 1-20000 km, section 0,1-1000 cm, mounted in axial-symmetric manner inside the pipeline with diameter 0,02-10 m made of dielectric material. To increase transferred voltage and power wave guide is made of electric-insulated cable with insulation thickness 3-300 mm, and space between wave guide and pipeline is filled with electric-insulating gas under pressure, for example, electronic gas. High-voltage line is made in form of one-wire wave duct with length 1-20000 km, section 0,01-1000 cm², mounted in axial-symmetric manner inside the pipeline with diameter 0,02-10 m of dielectric material, and contains electric screen, made in form of multiple electric-insulated from each other non-closed conductive cylinder-shaped covers, total length of which is equal to length of wave guide, and length of each conducting cover is 1-1000 meters.

EFFECT: improved efficiency, decreased losses and improved reliability of transferring of electric energy along underground or underwater cable.

6 cl, 5 dwg

Description

The invention relates to a method and apparatus for transmitting electrical energy.

A device for transmitting electrical energy containing a 50 Hz alternating current generator, a transformer substation at the beginning and end of a high voltage cable line is known. The presence of a metal sheath in the cable limits the propagation of electromagnetic waves in a limited space between live elements and the sheath.

The consequence of this is significantly lower values of wave impedance and an increase in capacitive conductivity in comparison with a high-voltage air line. For 35-220 kV cable lines, the charging power increases by 8-50 times compared to the overhead line, which limits the maximum length of AC cable lines to 25 km. Excessive reactive power requires the use of shunt reactors.

The presence of a protective shell worsens the conditions of heat removal from the current-carrying cable element and reduces the value of the transmitted power by 1.4-1.7 times in comparison with the air line at the same voltage and wire cross-section (Electrical Manual. T3. Ed. MEI, M., 2002 Cable power lines, p.815-818).

The closest in technical essence to the present invention is a method of powering electrical devices using an alternating voltage generator connected to a consumer, in which the voltage of the generator is supplied to the low voltage winding of the high-frequency transformer converter, and one of the terminals of the high-voltage winding is connected to one of the input terminals of the electrical device, in this case, by changing the frequency of the generator, resonance oscillations in the formed elec trotehnicheskoy chain.

A device that implements this method is an AC voltage source with an adjustable frequency, a high-frequency transformer, one output of the high-voltage section of which is isolated, and the second is designed to supply energy to the consumer (S. Avramenko. Power supply method for electrical devices and a device for its implementation. RF patent No. 2108649 dated 04/11/1995).

Instead of a Tesla step-down transformer, a diode-capacitor unit can be used, which is used in voltage doubling circuits and is made of two counterclockwise diodes connected to a capacitor, the common point of the diodes is connected to a power source (Electrical Manual. M., Energy, vol. 1, 1971, p. 871). When an alternating voltage is applied to the diode-capacitor unit, the positive wave of the alternating reactive current goes to one capacitor plate, and the negative wave goes to the other plate. The capacitor will accumulate charges until the voltage at its terminals reaches the positive and negative amplitudes of the alternating voltage at the common point of the diodes, then the diodes will be locked and the capacitor charge will stop. This is how the known rectifier circuit with voltage doubling works.

The disadvantage of all known methods and devices for transmitting electric energy is that they do not allow highly efficient transmission of electric energy over a long distance over the air line in rainy weather, as well as through an underground or underwater cable, due to the loss of high-frequency energy on the line resistance and line length in a conductive environment.

The objective of the invention is to increase efficiency, reduce losses and increase the reliability of the transmission of electrical energy through an underground or underwater cable.

This result is achieved by the fact that in a method for transmitting electric energy, including converting electric energy by voltage and frequency from an electric generator, transmitting electric energy by high voltage line and converting electric energy by voltage and frequency from a consumer, electric energy is transferred underground or under water in the resonant mode at a resonant frequency of 50 Hz - 50 kHz and a voltage of 1-1000 kV, a current density of 1-500 A / mm ² in a single-conductor electrically insulated to Abel.

To reduce losses in the device for transmitting electric energy, containing a frequency converter and a resonant circuit of a step-up transformer, a high-voltage line, a resonant circuit of a step-down transformer and a load, a high-voltage line is performed underground or under water in the form of an insulated single-conductor multicore cable with a length of 1-20000 km cross-section 0 , 01-1000 cm ² , in which the cable diameter is 5-100 times the diameter of the conductor.

In another embodiment of a method for transmitting electric energy, including converting electric energy by voltage and frequency from an electric generator, transmitting electric energy by high voltage line and converting electric energy by voltage and frequency from a consumer, transferring electric energy is carried out underground or under water in a resonant mode at a resonant frequency of 50 Hz - 50 kHz and a voltage of 1-10000 kV, a current density of 1-500 A / m along an axisymmetric single-conductor waveguide inside an airtight empty telogo dielectric cylindrical passage in the insulating gas atmosphere. To improve the efficiency of the method of transferring electric energy, the transmission of electric energy through a waveguide is carried out in an atmosphere of SF6 gas at a pressure of 1-10 kg / cm ² .

In yet another embodiment of a method for transmitting electric energy, including converting electric energy by voltage and frequency from an electric generator, transmitting electric energy by high voltage line and converting electric energy by voltage and frequency from a consumer, electric energy is transmitted at a frequency of 50 Hz to 50 kHz and voltage 1-10000 kV, current densities 1-500 A / cm ² over a single electrostatically shielded and electrically insulated axisymmetric single-conductor surface wave waveguide inside a hollow cylindrical screen and a sealed dielectric channel in an atmosphere of an isolated gas.

To increase the transmitted power, the transmission of electrical energy is carried out by a waveguide in an atmosphere of gas at a pressure of 1-10 kg / cm ² .

In a device for transmitting electric energy containing a frequency converter and a resonant circuit of a step-up transformer, a high-voltage line, a resonant circuit of a step-down transformer and a load, the high-voltage line is made underground or under water in the form of a single-conductor waveguide with a length of 1-20000 km and a cross-section of 0.01-1000 cm ² , mounted axisymmetrically inside a pipeline with a diameter of 0.02-10 m of a dielectric material, such as cross-linked polyethylene or fiberglass.

To increase the transmitted voltage and power in the device for transmitting electric energy, the waveguide is made of an electrically insulated cable with an insulation thickness of 3-300 mm, and the space between the waveguide and the pipeline is filled with electrically insulating gas under pressure, such as SF6 gas.

In an embodiment of a device for transmitting electrical energy comprising a frequency converter, a resonant circuit of a step-up transformer, a high voltage line, a resonant circuit of a step-down transformer and a load, the high-voltage line is made in the form of a single-conductor waveguide with a length of 1-20000 km, a cross-section of 0.01-1000 cm ² , installed axisymmetrically inside the pipeline with a diameter of 0.02-10 m of dielectric material, and contains an electric screen made in the form of a plurality of electrically insulated from each other conductive-closed cylindrical shell, total length equal to the length of the waveguide, and the length of each conductive sheath is 1-1000 m. To reduce the loss in the device for transmitting electrical energy each shell electrical screen is connected to ground via the inductor.

A method and apparatus for transmitting electrical energy are illustrated in the drawing, where:

figure 1 shows a block diagram of a method and device for transmitting electrical energy through a single-conductor underground waveguide;

figure 2 is a cross section of a single-conductor waveguide;

figure 3 is a cross section of an underground single-conductor waveguide with a cylindrical hollow dielectric sheath;

figure 4 is a cross section of an underground single-conductor waveguide with an electrostatic screen;

figure 5 is a connection diagram of an electrostatic screen with inductors and capacitance.

In Fig. 1, an electric high-frequency generator 1 creates resonant oscillations in a series resonant circuit 1 consisting of a capacitance 3 and a low-voltage winding 4, a Tesla high-voltage transformer 5. One of the terminals 6 of the high-voltage winding 7 adjacent to the low-voltage winding is connected to the terminal 8 of the low-voltage winding 4, and the other terminal 9 of the high-voltage winding is connected to an underground single-conductor electrically insulated waveguide 10. At a consumer of electric energy, a single-conductor waveguide 10 is connected to an internal they lead 11 of the high voltage winding 12 down high voltage Tesla transformer 13. The other terminal 14 of high voltage winding 12 is connected to ground 15. The low voltage winding 16 of the transformer 13 and the capacitance 17 form a receiving resonant circuit 18 which is connected to the load 19.

Figure 2 shows a cross section of a single-conductor waveguide 10 installed underground 15 or under water. The waveguide consists of a metal stranded conductor 20, a winding 21 of an insulating material, for example, cross-linked polyethylene. To reduce current losses through the capacitance 22 of the waveguide 10 with respect to the earth 15, the ratio of the diameter D of the outer shell of the waveguide 10 and the diameter d of the metal stranded conductor 20 is

Figure 3 shows a cross-section of a single-conductor waveguide 10, installed underground 15 or under water, axisymmetrically in a hollow cylindrical shell 23 of electrical insulating material, such as cross-linked polyethylene or fiberglass. A single-conductor waveguide 10 consists of a metal stranded conductor 20 and a sheath 21 of electrical insulating material. The space 24 between the single-conductor waveguide 10 and the hollow cylindrical shell 23 is filled with an insulating gas, such as SF6 gas, at a pressure of 1-10 kg / cm ² . The waveguide 10 is fixed in the center of the hollow cylindrical shell 23 using dielectric stops 25.

Figure 4 shows the cross section of a single-conductor waveguide 10, mounted underground 15 or under water axisymmetrically using dielectric stops 25 in a hollow cylindrical shell 23 of electrical insulating material. In the space between the waveguide 10 and the sheath 23, open, isolated from each other, electrostatic screens 26 of a metal sheet or mesh are installed. The screens are mounted on dielectric stops 25 and have a length of 1-1000 m. The total length of all screens is equal to the length of the underground part of the waveguide 10.

Figure 5 shows the connection diagram of the electrostatic shields 26 of the underground waveguide with inductors L _e , which serve to compensate for the capacitance of the screen With _e . Screens 26 are placed on the outer surface of the additional cylindrical shell 27 of electrically insulated material, such as cross-linked polyethylene or fiberglass, and are placed inside the main hollow dielectric cylindrical shell 23.

The device operates as follows.

Generator 1 generates an electric current of increased frequency 50 Hz - 50 kHz. In a series resonant circuit 2 at a resonant frequency of 50 Hz - 50 kHz, the voltage at the inductance of the low-voltage winding 4 of the Tesla transformer 5 increases. The voltage increase on the winding 4 compared to the voltage V _{o of the} generator 1 is QV _o , where Q is the quality factor of circuit 2. This the voltage increases n times in the high-voltage winding 7 of the Tesla transformer 5, where n is the transformation coefficient. Thus, the total voltage U ₂ at the inner terminal 9 of the high voltage winding 7 will be V ₂ = αQU ₀ n, where α is the coupling coefficient of the windings 4 and 7, 0 <α <1.

где

Для f=1 кГц, λ=300 км, L_Abмин=150 км. Для снижения емкости в волноводе 10 по отношению к Земле 15 уменьшают диаметр d металлического проводника 20 волновода 10 и увеличивают диаметр D изолирующей оболочки 21 волновода 10 до соотношения

Таким образом, передача электрической энергии происходит между двумя резонансными контурами по волноводной линии связи, а роль трансформаторов Тесла 5 и 13 сводится к созданию не симметрии потенциалов на выводах 9 и 11. На поверхности однопроводникового волновода в связи с наличием фазового сдвига между волнами тока и напряжения возникают поверхностные заряды, которые создают кулоновые возбуждающие электрические поля, и эти поля приводят к появлению кулоновых токов в проводнике. В проводнике возникает потенциальное электрическое поле, которое обеспечивает перенос зарядов и ток в волноводе. Описанные процессы имеют электростатическую природу и сопровождаются малыми потерями в волноводе. Поверхностные заряды в однопроводниковом волноводе изменяются во времени и создают в пространстве, окружающем проводник, ток смещения, который замыкается током в проводнике, возбуждаемым потенциальным электрическим полем. Токи смещения, в отличие от токов проводимости, не сопровождаются выделением джоулева тепла (Тамм Е.И. Основы теории электричества. - М.: Наука, 1976, с.133, 397-400. Сотников В.В. Источники кулонова поля в проводниках и их влияние на электрический ток. Известия РАН. Энергетика. 2002 г., № 7, с.104-111).At the terminal 6 of the high-voltage winding 7, a current antinode and a voltage node arise, and this terminal 6 is connected to the terminal 8 of the low-voltage winding 4. The voltage and current with a phase shift of 90 ° from terminal 9 of the high-voltage winding 7 are fed to a single-conductor waveguide 10 and transmitted through a Tesla 13 transformer into the resonant circuit 18. The total length L _{AB of the} waveguide 10 and the high voltage windings 7 and 12 of the two transformers should be an integer number of half waves:

Where

For f = 1 kHz, λ = 300 km, L _Abmin = 150 km. To reduce the capacitance in the waveguide 10 with respect to the Earth 15, reduce the diameter d of the metal conductor 20 of the waveguide 10 and increase the diameter D of the insulating shell 21 of the waveguide 10 to the ratio

Thus, the transfer of electrical energy occurs between two resonant circuits along the waveguide communication line, and the role of Tesla transformers 5 and 13 is reduced to the creation of potential symmetry at terminals 9 and 11. On the surface of a single-conductor waveguide due to the presence of a phase shift between current and voltage waves surface charges arise that create coulomb exciting electric fields, and these fields lead to the appearance of coulomb currents in the conductor. A potential electric field arises in the conductor, which provides charge transfer and current in the waveguide. The described processes are electrostatic in nature and are accompanied by small losses in the waveguide. Surface charges in a single-conductor waveguide change in time and create a bias current in the space surrounding the conductor, which is closed by the current in the conductor, excited by a potential electric field. Bias currents, unlike conduction currents, are not accompanied by the release of Joule heat (Tamm E.I. Fundamentals of the theory of electricity. - M .: Nauka, 1976, p.133, 397-400. Sotnikov VV Sources of the Coulomb field in conductors and their influence on electric current. Izvestia RAN. Energy. 2002, No. 7, pp. 104-111).

Therefore, the current density in a single-conductor waveguide 10 is 10-100 times higher than the current density in conventional cable lines and can be 10-500 A / mm ² . The minimum diameter of the conductor 20 of the waveguide is selected from the condition of mechanical strength equal to 1 mm The maximum voltage for the waveguide in Fig. 2 is 10 ⁶ V, for the waveguides in Figs. 3 and 4 - 10 ⁷ V. The resonant frequency of the underground transmission of electric energy is 50 Hz - 50 kHz at an optimal frequency of 150-1500 Hz. The maximum waveguide length is 20,000 km and is limited by radiation losses and leakage currents through the capacitance of the conductor 20 of the waveguide 10 with respect to the Earth. These losses decrease with decreasing frequency to 150-1500 Hz. The radiation loss of a line with a length of 20,000 km is determined by the formula:

where n is the number of half waves;

I _eff is the effective current in the line.

We take the effective current in the line I _eff = 3000 A, voltage U = 10 ⁶ B, power R _l = 3000 · 10 ⁶ kW, frequency f = 0.6 kHz, wavelength λ = 500 km, the number of half-waves along the line length n = 80. Calculation formula gives P _rad = 2245.4 kW or in relative units:

When using SF6 gas at a pressure of 1-10 kg / cm and the design of the waveguide 10 according to FIGS. 3 and 4, the maximum voltage on the waveguide will be 10,000 kV. Electrostatic shielding of the electric field of the waveguide 10, according to figure 4 will significantly reduce the effect of the Earth 15 or water on energy loss. To reduce the capacitance of the screens 26 and the waveguide 10 with respect to the Earth 15, the screens 26 are connected to the Earth 15 using the inductance L _e . The value of the inductance L _e choose from the conditions:

where C _e is the capacitance of the screen 26 with respect to the Earth, af _res is the resonant frequency.

The method and design of the device under consideration allow maximum terawatt flows of electric power to be transmitted between the continents of the Earth, and also reduce the dependence of power supply on weather conditions.

Claims (11)

1. A method of transmitting electric energy, including converting electric energy by voltage and frequency from an electric generator, transmitting electric energy by high voltage line and converting electric energy by voltage and frequency from a consumer, characterized in that the electric energy is transmitted underground or under water in the resonant mode at a resonant frequency of 50 Hz - 50 kHz and a voltage of 1-1000 kV, a current density of 1-500 A / mm through a single-wire electrically insulated cable. 2. A method of transmitting electric energy, including converting electric energy by voltage and frequency from an electric generator, transmitting electric energy by high voltage line and converting electric energy by voltage and frequency from a consumer, characterized in that the electric energy is transmitted underground or under water in resonant mode at a resonant frequency of 50 Hz - 50 kHz and a voltage of 1-1000 kV, a current density of 1-500 A / mm ² for a single electrically insulated axisymmetric and single-conductor a waveguide inside a sealed hollow dielectric cylindrical channel in an atmosphere of an isolated gas. 3. The method of transmitting electric energy according to claim 2, characterized in that the transmission of electric energy through the waveguide is carried out in an atmosphere of gas at a pressure of 1-10 kg / cm ² . 4. A method of transmitting electrical energy, including converting electrical energy by voltage and frequency from an electric generator, transmitting electrical energy by high voltage line and converting electrical energy by voltage and frequency to a consumer, characterized in that electric energy is transmitted at a frequency of 50 Hz to 50 kHz and a voltage of 1-10000 kV, a current density of 1-500 A / mm ² along a single electrostatically shielded and electrically insulated axisymmetric single-conductor surface wave waveguide s inside a hollow cylindrical screen and a sealed dielectric channel in an atmosphere of an isolated gas. 5. A device for transmitting electrical energy containing a frequency converter and a resonant circuit of a step-up transformer, a high voltage line, a resonant circuit of a step-down transformer and a load, characterized in that the high-voltage line is made underground or under water in the form of an insulated single-conductor multicore cable 1-20000 km long with a cross section of 0.01-1000 cm ² , in which the cable diameter is 5-100 times the diameter of the conductor. 6. A device for transmitting electrical energy according to claim 5, characterized in that the waveguide is made of an electrically insulated cable with an insulation thickness of 3-300 mm. 7. A device for transmitting electrical energy containing a frequency converter and a resonant circuit of a step-up transformer, a high voltage line, a resonant circuit of a step-down transformer and a load, characterized in that the high-voltage line is made underground or under water in the form of a single-conductor waveguide with a length of 1-20000 km, cross-section 0.01-1000 cm ² installed axisymmetrically inside the pipeline with a diameter of 0.02-10 m of a dielectric material, such as polyethylene or fiberglass. 8. The device for transmitting electrical energy according to claim 7, characterized in that the waveguide is made of an electrically insulated cable with an insulation thickness of 3-300 mm. 9. The device for transmitting electrical energy according to claim 7, characterized in that the space between the waveguide and the pipe is filled with electrically insulating gas under pressure, such as SF6 gas. 10. A device for transmitting electrical energy containing a frequency converter, a resonant circuit of a step-up transformer, a high voltage line, a resonant circuit of a step-down transformer and a load, characterized in that the high-voltage line is made in the form of a single-conductor waveguide with a length of 1-20000 km, section 0.01-1000 cm, installed axisymmetrically inside the pipeline with a diameter of 0.02-10 m of dielectric material and contains an electric screen made in the form of a plurality of electrically insulated from each other hollow conductive cylindrical shells, the total length of which is equal to the length of the waveguide, and the length of the conductive shells is 1-1000 m. 11. The device for transmitting electrical energy according to claim 10, characterized in that each shell of the electric screen is connected to the ground using an inductor.

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