WO2021053502A1

WO2021053502A1 - Method and apparatus for transmission of electrical energy (embodiments)

Info

Publication number: WO2021053502A1
Application number: PCT/IB2020/058552
Authority: WO
Inventors: Oleg Vladimirovich Trubnikov; Vladimir Zakharovich Trubnikov
Original assignee: Folquer Holdings Limited
Priority date: 2019-09-17
Filing date: 2020-09-15
Publication date: 2021-03-25
Also published as: RU2718779C1

Abstract

The invention relates to electrical engineering, specifically to methods and apparatuses for wireless transmission of electrical energy using resonant half-wave techniques between stationary objects, and between fixed power sources and mobile devices that receive electrical energy. The technical result of the invention is to develop wireless methods and apparatuses for charging electrical energy accumulators in stationary or mobile electrical consumers, which have uniform magnetic flux intensity over the active area of a transmitting module, high efficiency of transmission of energy, and low radiation levels. The technical result is achieved by way of including into transmission of electrical energy from a source to an accumulator, controlled by frequency of the converter of source current, of transmitting and receiving modules connected to each other by magnetic resonance coupling, and a current converter that converts a higher-frequency current format to the current required for the operation of the accumulator in the receiving module, wherein the magnetic resonance winding of the transmitting module is made in the form of a flat spiral of two wires wound from center to periphery, the magnetic resonance winding of the receiving module is made in the form of flat single- or double-wire spiral, standing waves of current and potential with a current antinode at the periphery of the winding are excited in the magnetic resonance winding of the transmitting module, energy is transmitted between the transmitting and the receiving modules. The terminals at the core of the double-wire spiral winding of the transmitting module are mutually isolated. Provided are 6 embodiments of charging apparatuses and 6 embodiments of charging methods.

Description

METHOD AND APPARATUS FOR TRANSMISSION OF ELECTRICAL ENERGY

(EMBODIMENTS)

FIELD OF INVENTION

The present invention relates to electrical engineering, specifically to apparatuses and methods for transmission of electrical energy using resonant techniques between stationary objects, and between stationary power sources and movable devices that receive electrical energy.

BACKGROUND OF INVENTION

The prior art provides a method and an apparatus for conversion and transmission of electrical energy via a single-wire line over long distances, which were developed by N. Tesla in 1897. (N. Tesla. US patent No. 593138). Electrical Transformer. Filed: March 20, 1897. Granted: November 2, 1897. N. Tesla. Patent No. 645576. System of transmission of electrical energy. Filed: September, 1897. Granted: March 20, 1900.

According to the inventions of N. Tesla, the system consists of two (transmitting and receiving) resonant transformers with resonant step-up windings which are single-layer spiral quarter-wave segments of long lines wound on cylindrical formers, and a wire connecting high- potential terminals of the resonant step-up windings. The low-potential terminals of the resonant quarter-wave windings of the both transformers are grounded immediately near the transformer structures. The low-voltage winding of the transmitting transformer is connected to the output of a elevated-frequency generator, which is a converter of energy of the source of electrical energy into alternating current electrical energy with a frequency that is equal to the resonant frequency of the resonant single-wire system for transmission of electrical energy. The low-voltage winding of the receiving transformer is connected to the energy-consuming load.

By connecting one of the terminals of single-layer high-voltage spiral windings to ground and the other terminals of these windings to the wire connecting the high-voltage terminals of the spiral windings, one enables the generation of standing waves of electromagnetic oscillations along the high-voltage windings with half-wave length determined by the components of the transmission system, which are included between the grounded terminals of the transmitting and receiving transformers.

The energy supplied to the transmission system from the source flows along the system to the load, and if it is only partly consumed or not consumed by the load, it is reflected back from the load into the transmission system. Electromagnetic oscillations shifted by one-half of the wave length and traveling towards each other interfere each other and produce a standing wave with current antinodes at the grounded terminals and a current node at the wire connecting the high- voltage terminals of the resonant quarter-wave transformers. The voltage half-wave is shifted in space and time domains relative to the current half-wave, and, therefore, the potential antinode is disposed at the high-voltage terminals of the transformers and the transmission line, and, respectively, the potential nodes are disposed at the grounded terminals of the transformers.

A disadvantage of the known method and apparatus for transmission of electrical energy is high energy losses in the ground connections of the low-potential terminals of the resonant spiral windings of the resonant transformers. Moreover, grounding a displacement current from the conductor of the transmission line results in losses in ground under the conductor of the line. Another disadvantage is a low-voltage winding due to losses therein and the requirement to arrange a serial resonant circuit between the generator and the resonant quarter-wave winding of the transmitting transformer.

Known are a method and apparatus for transmission of electrical energy by way of generating elevated-frequency resonant oscillations in a circuit consisting of a high-frequency generator and two (step-up and step-down) high-frequency resonant transformers, increasing the potentials at both terminals of the high-voltage resonant winding of the step-up high-frequency resonant transformer, transmitting the high-voltage potential and electrical energy via a single- wire line to the step-down high-frequency resonant transformer, reducing the potential and transmitting electrical energy to the load by connecting a low-voltage winding of the transformer to the two terminals of the load, wherein the electromagnetic energy resonant oscillations with a wavelength l = L_AB/2n, where n is an integer, L_AB is the circuit length between the unconnected terminals A and B of the high-voltage windings, made in the form single-layer spirals, of the high- frequency resonant transformers, transmit electrical energy from the generator, tuned to the frequency of the resonant transformers, from the step-up transformer to the step-down transformer via a single-wire line, independent of ground, by way of disposing the low-voltage windings of the step-up and the step-down high-frequency resonant transformers at the middle of the high- voltage resonant windings and converting current in the single-wire line into an active current at the load (Method and apparatus for transmission of electrical energy (embodiments). Patent No. 2572360.RU C2. H02J3/00. Trubnikov V.Z.(RU), Strebkov D.S. (RU), Nekrasov A.I. (RU). Filed: 18.10.2013 Granted: 08.12.2015.)

A disadvantage of the known method and apparatus for transmission of electrical energy is the presence of low-voltage windings and a high-potential single-line transmission line that require poles with high insulating strength against ground.

Another disadvantage of the known method and apparatus is a high capital investment that can be returned only when the known method is implemented globally, whereas the application of the method is problematic for transmission of electrical energy in close distances, e.g. 5-30 km. The most close solution to the proposed one is a known resonant method and apparatus for transmission of electrical energy from the source of electrical energy to the receiver of electrical energy using a frequency converter, transmitting and receiving Tesla transformers, and a single- wire line, wherein the single-wire line is included between the low-potential terminals of the transmitting and receiving Tesla transformers. An excitation winding is used to excite resonant oscillations, in the resonant winding of the transmitting Tesla transformer, with a current antinode at the low-potential terminal; the current antinode supplies the single-wire line, electrical energy is transmitted along the single-wire line to the receiving Tesla transformer, resonant oscillations with a current antinode at the low-potential terminal are excited in the receiving transformer, energy is transmitted to the load using the step-down winding, wherein the high-potential terminals of the Tesla transformers are remained unconnected. Method and apparatus for transmission of electrical energy. Patent No. 2577522.RU.C2. Trubnikov V.Z.(RU) Strebkov D.S. (RU) Nekrasov A.I. (RU) Rutskoy A.S. (RU) Moiseev M.V. (RU) Filed: May 19, 2014. Granted: March 20, 2016.

A disadvantage of the known method and apparatus is the presence of low-voltage windings in the transmitting and receiving Tesla transformers, as a result of which fact four resonant devices line up in series along the electrical energy transmission channel from the energy source to the load: a serial resonant circuit of the transmitting low-voltage winding connected using mutual induction to a quarter-wave resonant high-potential winding of the transmitting Tesla transformer, the low-potential terminal of which is connected using the electrical energy transmission lines to the low-potential terminal of a quarter-wave high-potential resonant winding of the receiving Tesla transformer, in the region of the current antinode of which there is disposed a low-potential step-down winding inductively connected to the high-potential winding, the low- potential winding supplies the load via an electrical capacitor that together with the step-down winding forms a low-voltage serial resonant circuit.

There is a certain technical difficulty in the procedure of resonance tuning of four resonant apparatuses. Sufficient efficiency can be achieved only through accurate resonance tuning of all four resonant systems and ensuring optimal mutual inductive connection between the low- and high-voltage windings of the transmitting and receiving Tesla transformers.

The objective of the present invention is to improve the efficiency of resonant electrical energy transmission, reduce copper consumption by removing step-down windings in the resonant quarter-wave Tesla transformers, simplify the design of the Tesla transformers, optimize resonance tuning of the transmitting and receiving Tesla transformers.

DISCLOSURE OF INVENTION The present invention improves the efficiency of resonant transmission of electrical energy and, primarily, over short and medium distances through application of a wave energy transmission mechanism by elevated-frequency currents via the low-potential terminals of quarter-wave windings. Thereby, the high-potential terminals of the quarter-wave windings remain unconnected. As a result of excluding low-voltage windings in the Tesla transformers, the copper consumption and, subsequently, the transformers' manufacturing cost are reduced. Since low-potential circuits are excluded, the expensive, high-power, high-frequency capacitors are not anymore required to manufacture the transmission system. As a result of halving the number of resonating objects, the procedure of resonance tuning of the transmission system is greatly simplified. Moreover, fewer resonating components allow more reliable and efficient transmission.

The above technical result is achieved by the fact that electrical energy is transmitted from the source of electrical energy to the receiver of electrical energy using a frequency converter, transmitting and receiving Tesla transformers, and a single-wire transmission line that is included between the low-potential terminals of the transmitting and receiving Tesla transformers, the source of electrical energy is used to excite resonant oscillations in the quarter-wave resonant winding of the transmitting Tesla transformer with a current antinode at the low-potential terminal, the current antinode supplies the single-wire line, electromagnetic energy is transmitted along the single-wire line to the receiving Tesla transformer, resonant oscillations are excited in the receiving Tesla transformer with a potential antinode at the high-potential terminal, wherein the source of electrical energy and receiver of electrical energy are included immediately into the transmission line in series, the source is in immediate proximity to the transmitting transformer, the receiver is in immediate proximity to the receiving transformer, wherein the high-potential terminals of the Tesla transformers are remained unconnected.

In another embodiment of the method and apparatus for transmission of electrical energy, the high-voltage terminals of the Tesla transformer are connected to solitary electrical capacitors, e.g. isolated conductive spheres or toroids. Long conductors can also be used as solitary electrical capacitors.

The essence of the proposed invention is explained by Fig. 1 and Fig. 2.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 shows an electrical diagram of a method and apparatus for transmission of electrical energy from the source of electrical energy to the receiver of electrical energy using a frequency converter, transmitting and receiving Tesla transformers, and a single-wire line that is included between the low-potential terminals of the resonant single-layer spiral windings of the Tesla transformers, wherein the source of electrical energy and receiver of electrical energy are included immediately into the transmission line.

Fig. 2 shows an electrical diagram of a method and apparatus for transmission of electrical energy from the source of electrical energy to the receiver of electrical energy using a frequency converter, transmitting and receiving Tesla transformers, and a single-wire line that is included between the low-potential terminals of the resonant single-layer spiral Tesla transformers, wherein the source of electrical energy and the receiver of electrical energy are included immediately into the transmission line, and the high-voltage terminals are connected using connecting conductors to spherical or toroid capacitors disposed above the ground, and the length of connecting conductors is at least 5 times longer than the diameter of spheres or toroids.

EMBODIMENT OF INVENTION

Fig. 1 is a diagram of electrical connections of components. A source 1 of electrical energy (in the attached diagram, industrial-grade 3-phase 380 V, 50-60 Hz mains supply is used as the source 1) is connected to the input of a frequency converter 2. The frequency converter 2 converts electrical energy from a 3-phase, 380 V, 50-60 Hz format into elevated-frequency (0.5-200 kHz) alternating current energy. The output of the frequency converter 2 is included into a transmitting single-wire line 4. An inverter module 16 and load 17 are included in series with the frequency converter 2 into the transmitting line 4. The transmitting line 4 with the beginning thereof is connected to the low-potential terminal 6 of the spiral winding 5 of the quarter-wave transformer 3. The single-wire line 4 with the end thereof is connected to the low-voltage terminal 15 of the single-layer spiral winding 13 of the resonant receiving Tesla transformer 14. The high-voltage terminals 7, 12 of the transmitting and receiving Tesla transformers 3 and 14 are remained unconnected. The spiral quarter-wave resonant windings 5 and 13 of the Tesla transformers 3 and 14 are single-layer induction coils with distributed electrical parameters.

Fig. 2 shows a diagram of electrical connections of the components of a resonant electrical energy transmission system using resonant Tesla transformers, the low-potential terminals of which are connected via a single-wire electrical energy transmission line, and the high-voltage terminals are connected via connecting conductors to solitary electrical capacitors. The source 1 of electrical energy is connected to the input of the frequency converter 2. The frequency converter 2 converts electrical energy from the format of the source 1 to an elevated-frequency (0.5...200 kHz) alternating current format. The output of the frequency converter 2 is included into a single-wire line 4. An inverter module 16 and load 17 are included in series with the frequency converter 2 into the transmitting line 4. The transmitting line 4 with the beginning thereof is connected to the low-potential terminal 6 of the spiral winding 5 of the quarter-wave transformer 3. The single-wire line 4 with the end thereof is connected to the low-voltage terminal 15 of the single-layer spiral winding 13 of the resonant receiving Tesla transformer 14. The high-voltage terminals 7 and 12 of the transmitting and receiving Tesla transformers 3 and 14 are connected to spherical or toroidal capacitors 9 and 10. The spiral quarter-wave resonant windings 5 and 13 of the Tesla transformers 3 and 14 are single-layer induction coils with distributed electrical parameters. The solitary electrical capacitors 9, 10 are connected using connecting conductors 8, 11 to the high-voltage terminals 7, 12 of the transmitting and receiving Tesla transformers 3 and

14.

The apparatus for transmission of electrical energy operates as follows. Electrical energy from the source 1 (Fig. 1) is supplied to the frequency converter 2 that functions as an elevated- frequency current generator with controllable current frequency and a "squarewave" voltage shape at the converter output. Generation of "squarewave"-shaped voltage allows the converter 2 to operate with minimum number of current switch operations. Since the resonant system is connected to the output terminals of the converter 2, the current at the output of the converter 2 is sine-shaped.

The frequency of converted current is equal to the individual resonance frequency of the quarter-wave resonant transformers 5, 13. As a result, the current excited in the electrical energy transmission line 4 builds up electric oscillations in the high-voltage resonant windings 5, 13 at their own frequency f₀. Since the windings 5, 13 are made as quarter-wave segments of a single- layer solenoid winding, the resonant frequency of the windings 5, 13 equals:

where f₀₁, f₀₂ are the individual resonance frequencies of the windings 5, 13, Hz;

L₀ is the inductance per unit length of the single-layer winding, H/m;

C₀ is the capacitance per unit length of the single-layer winding, F/m b is the length of the windings 5, 13, m.

The physical sense of Equation 1 is as follows. A single-layer solenoid winding having distributed (per unit length) inductance ( L₀) and capacitance ( C₀) enable the generation and transmission therealong of electromagnetic energy waves. The wave propagation velocity along an infinitely long solenoid winding equals:

where V₀ is the wave velocity, m/sec. A specific winding has a certain length (b). Therefore, the time of wave travel through a winding having length b is:

Since it takes a quarter-period for the wave to travel the length of the high-voltage quarter- wave windings, the full oscillation period (quadruple travel) is:

The frequency that corresponds with the resulting period is:

Electric current excited by the converter 2 in the transmitting line 4 excites the resonant windings 5, 13 and flows via the inverter module 16 and the load 17 included into the transmission line 4. The transmitting 3 and the receiving 14 Tesla transformers function as electric reflectors on the both ends of the line 4. A sine alternating current at the frequency f₀ filtered from the squarewave by the resonant quarter-wave windings 5, 13, thus, passes through the inverter module 16. The frequency converter 2 that functions as the source 2 of energy, and the inverter module 16 that consumes energy and passes the same to the load 17 such that the converter 2 supplies energy to the line 4, the load 16-17 consumes by taking energy from the line 4.

The principle of operation of the energy transmission system shown in Fig. 2 is similar to that of the system shown in Fig. 1. The difference is that the high-voltage terminals 7, 12 of the quarter-wave resonant Tesla transformers 5, 13 are loaded to the ungrounded solitary electrical capacitors 9, 10 using the conductors 8, 11. The capacitors can be spheres, toroids, long conductors, and the like.

In case of spheres, the capacitance is determined by the following equations:

C_sphere = 4pe₀ · a, where C_sphere is the natural capacitance of a solitary conductive sphere, F; a is the conductive sphere radius, m; e₀ is the vacuum permittivity, e₀ = 8.85·10^-12 F/m.

Application of load to the capacitors 9, 10 of the quarter-wave resonators 5, 13 leads to reduced resonant frequency (1) and wave resistance Z_C of the transformers. Reducing the wave resistance Z_C can be useful when the energy capacity of the transmission system is required to be increased.

Example 1 of an embodiment of the method for transmission of electrical energy. A quarter- wave winding is made of a PEV-2 wire in the form of a single-layer spiral. The wire diameter is 0.63 mm, the diameter of a winding former is 145 mm, the winding length is 900 mm. The former is made of fiberglass laminate and has a length of 1000 mm. The number of turns is 1300. The resonant frequency is 175 kHz.

The both transformers are identical to each other. The transformers are connected by a single-wire cable of 100 m long. A 96 W, 220 V incandescent bulb is applied as a load. The output current frequency is 175 kHz with a ±50% deviation. The voltage shape is squarewave. During the operation, the high-voltage terminals of the both resonant transformers were isolated and remained unconnected.

The potential of the transmitting single-wire line was 0.1 kV. The current in the transmission line was 0.4 A. The potentials at the high-voltage terminals of the resonant transformers were 3.5 kV.

Example 2 of an embodiment of the method for transmission of electrical energy. A resonant quarter-wave transformer with a high-voltage terminal connected to a sphere was used as a transmitting transformer. The sphere was made of an aluminum sheet by cold moulding. The sphere diameter is 0.4 m, the distance to the high-voltage end of the quarter-wave transformer is 2.0 m. The quarter-wave winding is made ofPEV-2 wire of 0.63 mm in diameter, in the form of a single-layer spiral. The former diameter is 145 mm, the winding length is 900 mm. The former is made of fiberglass laminate. The former length is 1000 mm. The number of turns is 1300. The resonant frequency is 95 kHz. A transformer having identical design parameters was used as a receiving transformer. The transformers are connected by a single-wire, low-potential electrical energy transmission line connected to the low-potential terminals of the quarter-wave windings of the resonant Tesla transformers. The single-wire line is made of a single-wire unshielded cable. The length of the transmitting cable is 100 m. A 96 W (220 V) incandescent bulb is used as a load. The output current frequency can deviate in the ±50% range. The output voltage shape is squarewave. The potential of the transmitting line is 0.15 kV. The current in the transmission line was 0.45 A. The potentials at the high-voltage terminals of the resonant transformers were 2.0 kV.

The proposed invention improves the efficiency of resonant transmission of electrical energy and, primarily, over short and medium distances through application of a wave energy transmission mechanism by elevated-frequency currents via the low-potential terminal of quarter- wave windings. Thereby, the high-potential terminals of the quarter-wave windings remain unconnected. As a result of excluding the low-voltage windings in the Tesla transformer, the copper consumption and, subsequently, the transformers' manufacturing cost are reduced. As a result of excluding low-potential circuits, there is no need in the expensive, high-power, high- frequency capacitors. As a result of halving the number of resonating objects, the procedure of resonance tuning of the transmission system is greatly simplified. Moreover, fewer resonating components allow more reliable and efficient transmission. Absence of high potential in the transmitting line results in reduced requirements for electrical strength. The capacitance of the single-wire cable to ground does not significantly affect the resonant windings because of low potential at the energy-conducting cable wire. Absence of grounding devices significantly reduces capital investments during the system commissioning.

The proposed method improves environmental situation along the electrical energy transmission line due to reduced strength of electrical fields.

Claims

WHAT IS CLAIMED IS:

1. A method for transmission of electrical energy comprising: transmitting electrical energy from the source of electrical energy to the receiver of electrical energy using a frequency converter, transmitting and receiving Tesla transformers, and a single-wire line; wherein the frequency converter and the receiver of electrical energy are connected in series by means of a single-wire line, one of the ends of the single-wire line is connected to the low-potential terminal of the transmitting Tesla transformer, and the other end is connected to the low-potential terminal of the receiving Tesla transformer, said method also comprising: excitating, by means of the frequency converter, resonance oscillations in the quarter-wave winding of the transmitting Tesla transformer with a current antinode at the low-potential terminal with the provision of supply of the single-wire line by the current antinode, transmitting electromagnetic energy along the single-wire line to the receiving Tesla transformer with the provision of exciting therein resonant oscillations with a potential antinode at the high-potential terminal, wherein the frequency converter is included into said line in immediate proximity to the transmitting Tesla transformer, the receiver of electrical energy is included into said line in immediate proximity to the receiving Tesla transformer, and the high-potential terminals of the both Tesla transformers are remained unconnected.

2. A method for transmission of electrical energy comprising: transmitting electrical energy from the source of electrical energy to the receiver of electrical energy using a frequency converter, transmitting and receiving Tesla transformers, and a single-wire line; wherein the frequency converter and the receiver of electrical energy are included in series into a single-wire line, one of the ends of the single-wire line is connected to the low-potential terminal of the transmitting Tesla transformer, and the other end is connected to the low-potential terminal of the receiving Tesla transformer, said method also comprising: excitating, by means of the frequency converter, resonance oscillations in the quarter-wave winding of the transmitting Tesla transformer with a current antinode at the low-potential terminal with the provision of supply of the single-wire line by the current antinode, transmitting electromagnetic energy along the single-wire line to the receiving Tesla transformer with the provision of exciting therein resonant oscillations with a potential antinode at the high-potential terminal, wherein the frequency converter is included into said line in immediate proximity to the transmitting Tesla transformer, the receiver of electrical energy is included into said line in immediate proximity to the receiving Tesla transformer, and the high-potential terminals of the both Tesla transformers are connected, by means of connecting conductors, to isolated solitary electrical capacitors.

3. The method for transmission of electrical energy according to Claim 2, wherein the length of connecting conductors is at least 5 times longer than the diameter of spheres or toroids.

4. An apparatus for transmission of electrical energy comprising: a source and a receiver of electrical energy, a frequency converter, transmitting and receiving Tesla transformers, and a single-wire line; wherein the frequency converter and the receiver of electrical energy are connected in series by means of a single-wire line, one of the ends of the single-wire line is connected to the low-potential terminal of the transmitting Tesla transformer, and the other end is connected to the low-potential terminal of the receiving Tesla transformer, the frequency converter is included into said line in immediate proximity to the transmitting Tesla transformer, the receiver of electrical energy is included into said line in immediate proximity to the receiving Tesla transformer, the high-potential terminals of the both Tesla transformers are remained unconnected, wherein when exciting by the frequency converter the resonance oscillations in the quarter- wave winding of the transmitting Tesla transformer with a current antinode at the low-potential terminal, the current antinode supplies the single-wire line, thereby resulting in transmission of electromagnetic energy along the single-wire line to the receiving Tesla transformer with the provision of exciting therein resonance oscillations with a potential antinode at the high-potential terminal.

5. An apparatus for transmission of electrical energy comprising: a source and a receiver of electrical energy, a frequency converter, transmitting and receiving Tesla transformers, and a single-wire line; wherein the frequency converter and the receiver of electrical energy are connected in series by means of a single-wire line, one of the ends of the single-wire line is connected to the low-potential terminal of the transmitting Tesla transformer, and the other end is connected to the low-potential terminal of the receiving Tesla transformer, the frequency converter is included into said line in immediate proximity to the transmitting Tesla transformer, the receiver of electrical energy is included into said line in immediate proximity to the receiving Tesla transformer, and the high-potential terminals of the both Tesla transformers are connected, by means of connecting conductors, to isolated solitary electrical capacitors.

6. The apparatus for transmission of electrical energy according to Claim 5, wherein the length of connecting conductors is at least 5 times longer than the diameter of spheres or toroids.