Wireless transmission of electricity according to Tesla theory. Wireless electricity amazes its creators

He discovered a law (after named after the discoverer by Ampere's law), showing that an electric current produces a magnetic field.

• V 2007 year, a research group led by Professor Marina Solyachich from wirelessly transmitted energy over a distance of 2 m with a power sufficient for the glow of a 60-watt light bulb, with an efficiency of 40%, using two coils with a diameter of 60 cm.
• V 2008 Bombardier introduced a wireless power transmission system called primove for use in trams and light rail engines.
• V 2008 In 2006, Intel employees reproduced the experiments of Nikola Tesla in 1894 and the experiments of the group of John Brown in 1988 on wireless power transmission for the glow of incandescent lamps with an efficiency equal to 75%.
• V 2009 Years ago, a consortium of interested companies called the Wireless Power Consortium developed a wireless low current power standard called "". Qi has come to be used in portable technology.
• V 2009 In 2010, the Norwegian company Wireless Power & Communication presented an industrial flashlight developed by it, capable of safely operating and recharging in a non-contact way in an atmosphere saturated with flammable gas.
• V 2009 The Haier Group introduced the world's first fully wireless LCD TV based on Professor Marina Solyachich's research on wireless power transmission and wireless home digital interface (WHDI).
• V 2011 The Wireless Power Consortium began expanding the Qi standard for medium currents.
• V 2012 A private St. Petersburg museum "Grand Model Russia" began its work, in which miniature car models received power supply wirelessly through a model of the roadway.
• V 2015 year, scientists from the University of Washington found that electricity can be transmitted through Wi-Fi technology.

Technologies

Ultrasonic method

The ultrasonic method of transmitting energy was invented by students at the University of Pennsylvania and presented to the general public for the first time at The All Things Digital (D9) in 2011. As with other methods of wirelessly transmitting something, a receiver and a transmitter were used. The transmitter was emitting ultrasound; the receiver, in turn, converted the audible into electricity. At the time of the presentation, the transmission distance reached 7-10 meters, and a direct line of sight of the receiver and transmitter was required. The transmitted voltage reached 8 volts; the resulting amperage is not reported. The ultrasonic frequencies used have no effect on humans. There is also no information about the negative effects of ultrasonic frequencies on animals.

Electromagnetic induction method

Wireless transmission of energy by electromagnetic induction uses a near electromagnetic field at distances of about one-sixth of a wavelength. Near-field energy itself is not radiating, but some radiation losses do occur. Besides, as a rule, resistive losses also take place. Due to electrodynamic induction, an alternating electric current flowing through the primary winding creates an alternating magnetic field that acts on the secondary winding, inducing an electric current in it. To achieve high efficiency, the interaction must be sufficiently close. As the secondary winding moves away from the primary, more and more of the magnetic field does not reach the secondary. Even over relatively short distances, inductive coupling becomes highly inefficient, wasting much of the transmitted energy.

An electrical transformer is the simplest device for wireless power transmission. The primary and secondary windings of the transformer are not directly related. Energy transfer occurs through a process known as mutual induction. The main function of the transformer is to increase or decrease the primary voltage. Contactless chargers for mobile phones and electric toothbrushes are examples of the use of the electrodynamic induction principle. Induction hobs also use this method. The main disadvantage of the wireless transmission method is its extremely short range. The receiver must be in close proximity to the transmitter in order to communicate effectively with it.

The use of resonance slightly increases the transmission range. With resonant induction, the transmitter and receiver are tuned to the same frequency. Performance can be further improved by changing the drive current waveform from sinusoidal to non-sinusoidal transient waveforms. Pulsed energy transfer occurs over several cycles. Thus, significant power can be transferred between two mutually tuned LC circuits with a relatively low coupling coefficient. The transmitting and receiving coils, as a rule, are single-layer solenoids or a flat spiral with a set of capacitors that allow you to tune the receiving element to the transmitter frequency.

A common application of resonant electrodynamic induction is to charge the batteries of portable devices such as laptop computers and cell phones, medical implants, and electric vehicles. The localized charging technique uses the selection of an appropriate transmitter coil in the structure of an array of multilayer windings. Resonance is used in both the wireless charging panel (transmitting circuit) and the receiver module (built into the load) to maximize energy transfer efficiency. This transfer technique is suitable for universal wireless charging boards for recharging portable electronics such as mobile phones. The technique is adopted as part of the Qi wireless charging standard.

Resonant electrodynamic induction is also used to power devices that do not have batteries, such as RFID tags and contactless smart cards, and to transfer electrical energy from the primary inductor to the Tesla transformer screw resonator, which is also a wireless transmitter of electrical energy.

Electrostatic induction

Laser method

In the event that the wavelength of electromagnetic radiation approaches the visible region of the spectrum (from 10 μm to 10 nm), energy can be transferred by converting it into a laser beam, which can then be directed to the photocell of the receiver.

Laser energy transmission has a number of advantages over other wireless transmission methods:

• energy transfer over long distances (due to the small value of the angle of divergence between narrow beams of a monochromatic light wave);
• ease of use for small products (due to the small size of a solid-state laser - photoelectric semiconductor diode);
• absence of radio frequency interference for existing communication devices such as Wi-Fi and cell phones (the laser does not create such interference);
• the ability to control access (only receivers illuminated by a laser beam can receive electricity).

This method also has a number of disadvantages:

• conversion of low-frequency electromagnetic radiation into high-frequency radiation, which is light, is ineffective. Converting light back to electricity is also inefficient, as the efficiency of solar cells reaches 40-50%, although the conversion efficiency of monochromatic light is much higher than that of solar panels;
• losses in the atmosphere;
• the need for a line of sight between the transmitter and the receiver (as with microwave transmission).

Laser power transmission technology has been primarily researched in the development of new weapons systems and in the aerospace industry, and is currently being developed for commercial and consumer electronics in low-power devices. Consumer wireless power transmission systems must meet the laser safety requirements of IEC 60825. To better understand laser systems, it should be borne in mind that the propagation of a laser beam is much less dependent on diffraction constraints, as spatial and spectral matching of lasers allows increase working power and distance, how wavelength affects focusing.

NASA Dryden Flight Research Center demonstrated the flight of a light unmanned aircraft model powered by a laser beam. This proved the possibility of periodic recharging by means of a laser system without the need to land the aircraft.

Alternating current can be transmitted through layers of the atmosphere that have an atmospheric pressure of less than 135 mm Hg. Art. The current flows by means of electrostatic induction through the lower atmosphere at about 2–3 miles (3.2–4.8 kilometers) above sea level and due to the flow of ions, that is, electrical conduction, through an ionized region located at an altitude above 5 km. Intense vertical beams of ultraviolet radiation can be used to ionize atmospheric gases directly above the two elevated terminals, resulting in plasma high-voltage power lines leading directly to the conductive layers of the atmosphere. As a result, an electric current is generated between the two elevated terminals, passing to the troposphere, through it and back to the other terminal. Electrical conductivity through the layers of the atmosphere is made possible by a capacitive plasma discharge in an ionized atmosphere.

Nikola Tesla discovered that electricity can be transmitted both through the earth and through the atmosphere. In the course of his research, he achieved lamp ignition at moderate distances and recorded the transmission of electricity at long distances. The Wardencliff Tower was conceived as a commercial transatlantic wireless telephony project and became a real demonstration of the possibility of wireless power transmission on a global scale. The installation was not completed due to insufficient funding.

Earth is a natural conductor and forms one conductive circuit. The return loop is realized through the upper troposphere and lower stratosphere at an altitude of about 4.5 miles (7.2 km).

The global system for the transmission of electricity without wires, the so-called World Wireless System, based on high electrical conductivity of plasma and high electrical conductivity of the earth, was proposed by Nikola Tesla at the beginning of 1904 and could well have caused the Tunguska meteorite, which arose as a result of a “short circuit” between a charged atmosphere and earth.

Worldwide wireless system

The early experiments of the famous Serbian inventor Nikola Tesla concerned the propagation of ordinary radio waves, that is, Hertz waves, electromagnetic waves propagating in space.

In 1919, Nikola Tesla wrote: “It is believed that I started work on wireless transmission in 1893, but in fact the two previous years I had been doing research and designing equipment. It was clear to me from the outset that success can be achieved through a series of radical solutions. High frequency generators and electrical oscillators had to be created in the first place. Their energy had to be converted into efficient transmitters and received at a distance by appropriate receivers. Such a system would be effective in the case of excluding any outside interference and ensuring its complete exclusivity. Over time, however, I realized that for devices of this kind to work effectively, they must be designed taking into account the physical properties of our planet. "

One of the conditions for creating a worldwide wireless system is the construction of resonant receivers. The grounded Tesla coil resonator and elevated terminal can be used as such. Tesla personally repeatedly demonstrated the wireless transmission of electrical energy from Tesla's transmitting to receiving coil. This became part of his wireless transmission system (US Patent No. 1,119,732, dated January 18, 1902, "Apparatus for Transmitting Electrical Power"). Tesla proposed to install more than thirty transmitting and receiving stations around the world. In this system, the take-up coil acts as a step-down transformer with a high output current. The parameters of the transmitting coil are identical to the receiving one.

Tesla's global wireless system aimed to combine power transmission with radio broadcasting and directional wireless communications, eliminating the many high-voltage power lines and facilitating the interconnection of electrical generators on a global scale.

see also

• WiTricity

Notes (edit)

1. "Electricity at the Columbian Exposition," by John Patrick Barrett. 1894, pp. 168-169 (eng.)
2. Experiments with Alternating Currents of Very High Frequency and Their Application to Methods of Artificial Illumination, AIEE, Columbia College, N.Y., May 20, 1891
3. Experiments with Alternate Currents of High Potential and High Frequency, IEE Address, London, February 1892 (English)
4. On Light and Other High Frequency Phenomena, Franklin Institute, Philadelphia, February 1893 and National Electric Light Association, St. Louis, March 1893
5. The Work of Jagdish Chandra Bose: 100 years of mm-wave research
6. Jagadish Chandra Bose
7. Nikola Tesla On His Work With Alternating Currents and Their Application to Wireless Telegraphy, Telephony and Transmission of Power, pp. 26-29. (English)
8. June 5, 1899, Nikola Tesla Colorado spring notes 1899-1900, Nolit, 1978 (English)
9. Nikola Tesla: Guided Weapons & Computer Technology (eng.)
10. The electrician(London), 1904 (eng.)
11. Scanning the Past: A History of Electrical Engineering from the Past, Hidetsugu Yagi
12. Tetelbaum S.I. On wireless transmission of electricity over long distances using radio waves // Electricity. - 1945. - No. 5. - S. 43-46.
13. A. A. Kostenko Quasi-optics: historical background and modern development trends // Radiophysics and radio astronomy. - 2000. - T. 5, No. 3. - S. 231.
14. A survey of the elements of power Transmission by microwave beam, in 1961 IRE Int. Conf. Rec., Vol. 9, part 3, pp. 93-105 (English)
15. IEEE Microwave Theory and Techniques, Bill Brown's Distinguished Career
16. Power from the Sun: Its Future, Science Vol. 162, pp. 957-961 (1968)
17. Solar Power Satellite patent
18. History of RFID
19. Space Solar Energy Initiative (eng.)
20. Wireless Power Transmission for Solar Power Satellite (SPS) (Second Draft by N. Shinohara), Space Solar Power Workshop, Georgia Institute of Technology (eng.)
21. W. C. Brown: The History of Power Transmission by Radio Waves: Microwave Theory and Techniques, IEEE Transactions on September, 1984, v. 32 (9), pp. 1230-1242 (English)
22. Wireless Power Transfer via Strongly Coupled Magnetic Resonances(English). Science (7 June 2007). Retrieved September 6, 2010. Archived February 29, 2012.,
    A new way of wireless transmission of electricity has been launched (Russian)... MEMBRANA.RU (8 June 2007). Retrieved September 6, 2010. Archived February 29, 2012.
23. Bombardier PRIMOVE Technology
24. Intel imagines wireless power for your laptop
25. wireless electricity specification nearing completion
26. Global Qi Standard Powers Up Wireless Charging - HONG KONG, Sept. 2 / PRNewswire /
27. TX40 and CX40, Ex approved Torch and Charger
28. Haier’s wireless HDTV lacks wires, svelte profile (video) (English),
    Wireless electricity amazes its creators (Russian)... MEMBRANA.RU (February 16, 2010). Retrieved September 6, 2010.

We present a device for transmitting electricity without wires with an efficiency of about 100%. In the future, the efficiency value of ≈ 100% will be substantiated and, of course, we demonstrate this value with our experimental device.

The importance of the problem of wireless transmission of electricity is beyond doubt - overcoming natural barriers (rivers, mountains and valleys); backup power supply, electric transport, solution of a number of problems of wireless power supply of household and industrial devices, etc. - all these are elements of the named problem.

A bit of history

For the first time, the problem of wireless transmission of electricity was identified at the dawn of the last century by N. Tesla. His demonstration device was based on the method of radiation and reception of electromagnetic waves by an open resonant circuit, which contains an antenna - a capacitance and a coil of wire - an inductance. The characteristic indicators of Tesla's device are as follows: efficiency = 4%, transmission distance - 42 km, maximum dimension of the tower-antenna - 60 m, wavelength - 2000 m. It is essential that in Tesla's device planet Earth is considered as one of the wires in the transmission of electricity , since the emission and reception of such long waves without grounding are not effective.

After Tesla's experiments, throughout the last twentieth century, all attempts to carry out wireless transmission of electricity with an acceptable efficiency were unsuccessful.

In the current decade, reports are directly or indirectly reported at the Masachusetts University of Technology under the leadership of M. Solyachich. Their work is based on the well-known induction, with the help of a magnetic field, method of transmission of electricity, which is implemented by resonant flat inductors. This method ideally provides an efficiency of 50%, with a transmission distance commensurate with the dimensions of the antenna coils. The characteristic indicators of their demonstration device are as follows: efficiency ≈ 40%, transmission distance - 2 m, size of antenna coils - 0.6 m, wavelength - 30 m.

Energetically closed system

In our device, as in Tesla's device, the carrier of energy is electromagnetic waves, i.e. the well-known Poynting vector is in effect.

The following is theoretically substantiated and experimentally confirmed: the transmitting and receiving antennas of the wireless power transmission device form an energetically closed system, partially including the energy of the Earth's electromagnetic field; Through the excitation (activation) of the Earth's electromagnetic field in this system, electricity is transferred from the transmitting antenna to the receiving antenna with an efficiency of ≈ 100% (Fig. 1).

FIG. one

FIG. 2

Using this antenna, it is easy to formulate a problem, the solution of which will ensure the transmission of electricity without wires:

1. Transmitting and receiving antennas must excite (activate) the Earth's electromagnetic field in a local (limited) region of space;

2. The excited electromagnetic field of the Earth must also be local in space and not consume energy (must be a standing electromagnetic wave between the transmitting and receiving antennas).

The solution to this problem is unrealistic with antennas created on the basis of spatial representations of Euclid's geometry with its famous 5th postulate - the postulate of parallel lines. This postulate in school textbooks reads: through a point that does not lie on a given straight line, only one straight line parallel to the given one can be drawn.

fig. 3

The celebrity of this postulate is that, starting from the 1st Art. BC, for 2000 years the best minds in the world tried unsuccessfully to prove it as a theorem. And so in 1826 the Russian Lobachevsky outlined the foundations of his geometry, in which the 5th postulate of Euclid's geometry was formulated, in fact, by his negation: through a point that does not lie on this line, you can draw at least two straight lines parallel to the given one.

fig. 4

And although this postulate is not very consistent with our spatial concepts, Lobachevsky's geometry is consistent and regularly serves physicists lately. For example, Lobachevsky's geometry is involved in the description of a huge number of phenomena from vibrations in mechanical transmission lines to the interaction of elementary particles and processes in the membrane of a living cell.

Pseudosphere

True, until 1863, for almost 40 years, Lobachevsky's geometry was perceived as something unrelated to reality. But, in 1863, the Italian mathematician Beltrami established that all the properties of the plane of Lobachevsky's geometry are realized on the surface of a pseudosphere - a geometric body whose properties are the same or opposite to those of a sphere. FIG. 5 shows a pseudosphere, and FIG. 6 its generatrix is ​​a tractrix with an asymptote X'X. If the radii of the great circles (parallels) of the pseudosphere and the sphere are equal, the volumes and areas of their surfaces can be quantitatively compared.

fig. 5

fig. 6

It is in the form of half-pseudospheres that the antennas of our device are made; we demonstrate a device with the following characteristics: efficiency = 100%, transmission distance - 1.8 m, maximum size of antenna coils - 0.2 m, wavelength - 500 m, grounding is optional.

It should be noted here that the totality of the above characteristics of the demonstration device contradicts the foundations of classical electrodynamics - radio engineering.

What properties of semi-pseudosphere antennas provide such characteristics of our device?

Among more than a dozen extraordinary properties of the pseudosphere, the following deserves attention, first of all:

An infinitely extended body of a pseudosphere in space has a finite volume and a finite surface area.

It is this property of the pseudosphere that allows using half-pseudosphere antennas to create a finite, limited in space, energetically closed system, which is a necessary condition for the transfer of energy from efficiency = 100%.

The second fundamental problem, which is solved in our device, concerns the environment that fills the mentioned energetically closed system. The bottom line is that only in quantum electrodynamics, the fruit of which are lasers and masers, is the medium considered active. On the contrary, in classical electrodynamics, the medium refers to passive objects; it is associated with attenuation, the loss of electromagnetic energy during propagation.

It is incredible, but true, in our device there is an activation of the electric and magnetic fields of the Earth. These fields are objects of the environment in our device, since they fill the mentioned energetically closed system. The activation of this environment is also a consequence of the properties of the pseudosphere.

The bottom line is that all points on the surface of the pseudosphere are, as mathematicians say, hyperbolic, discontinuous in space. With regard to the semi-pseudosphere antennas of our device, this is equivalent to discontinuities, quantization of the electric and magnetic fields at each point of the winding wire of the coils of the semi-pseudosphere antennas. This leads to electromagnetic disturbances - waves, the length of which is commensurate with the diameter of the winding wire of the coils of half-pseudosphere antennas, i.e. in practice, the length of such waves is on the order of 1 mm or less. Such electromagnetic waves, as evidenced by theory and practice, are capable, through the polarization of air molecules or directly, to activate the Earth's electromagnetic field and thereby compensate for the loss of electromagnetic energy on the way of its transmission in our device. This is also necessary to explain the efficiency = 100%.

Not only that, we have declared a generator of excess electromagnetic energy, the energy conversion coefficient (KPI) of which is more than 400%; those. comparable to the KPIs of known heat pumps.

And about the last, third task, which is solved in our device.

It is well known that energy is carried in space only by a traveling electromagnetic wave, a wave in which the electric and magnetic fields are in phase. This condition cannot be realized at a distance of 1.8 m at a wavelength of 500 m. But it is also well known that the speed of a traveling electromagnetic wave along a straight or curved conductor slows down and decreases in comparison with the speed in free space; the wavelength also decreases. This effect is widely used in electrical radio engineering in the so-called slow-wave systems. The wavelength reduction in these systems ranges from tenths of a unit with straight wires to 30 units with curved (spiral) wires.

It is the effect of slowing down, reducing the wavelength that allows us to form a traveling wave at short distances in our device.

Indeed, the wavelength of our demonstration device is reduced to the length mentioned above , which forms a running, energy-carrying electromagnetic wave in our device. The wave reduction factor in this case is units. Such a huge decrease in wavelength also explains the experimental fact that our device works effectively even without grounding the transmitter and receiver of electricity.

Another amazing property of the pseudosphere is involved in the operation of our device:

the volume of the pseudosphere is half the volume of the sphere, while the areas of their surfaces are equal.

It follows from this property that the volume of the sphere, limited by its own surface area, contains two volumes of the pseudosphere, limited by two combined proper surface areas and the third area of ​​the said sphere. This allows us to represent the volume of the sphere around the Earth, filled with the electric and magnetic fields of the Earth, two volumes of the pseudosphere and, each of which is limited by areas and contains half of the electric and magnetic fields of the Earth (Fig. 7). Given this fact and the fact that our device is inevitable only on one side of the earth, it is argued that the antennas of our device interact only from half of the Earth's electric and magnetic fields. At the same time, one should not assume that the second half of these fields are inactive. The following is convincing of this below.

fig. 7

Let us recall that most of the laws of physics are formulated for inertial reference systems in which time is irrelevant (absolute), space is isotropic, the speed of rectilinear motion of electromagnetic waves (light) is absolute, etc. Within the framework of inertial reference systems, it is well known that in free space, when a traveling electromagnetic wave is reflected, a standing wave is formed, in which a separately standing electric wave and a separately standing magnetic wave are distinguished. When the length of the traveling wave is equal, the lengths of the standing electric and magnetic waves are equal to half the length of the traveling one, i.e. ... It is also essential that the period of these standing waves is equal to the period of the traveling wave, i.e. , since the period of the standing wave consists of the sum of two half-periods of the direct and reflected half-waves.

The fact of calculating, rather than experimentally determining, a quantity with an accuracy that depends on the accuracy of determining the length of a day on Earth allows a completely new look at a number of problems in physics.

According to history, the revolutionary technological project was frozen due to Tesla's lack of adequate financial capabilities (this problem haunted the scientist almost all the time he worked in America). Generally speaking, the main pressure on him came from another inventor - Thomas Edison and his companies, which promoted DC technology, while Tesla was engaged in AC current (the so-called "War of currents"). History has put everything in its place: now alternating current is used in urban power grids almost everywhere, although echoes of the past reach our days (for example, one of the stated reasons for the breakdowns of the notorious Hyundai trains is the use of direct current power lines on some sections of the Ukrainian railway).

The Wardenclyffe tower, in which Nikola Tesla conducted his experiments with electricity (photo 1094)

As for the Wardenclyffe Tower, according to legend, Tesla demonstrated to one of the main investors J.P. Morgan, a shareholder of the world's first Niagara hydroelectric power station and copper plants (copper, as you know, is used in wires), a working installation for wireless transmission of current, the cost of which for consumers would be (if such installations on an industrial scale) are much cheaper for consumers, after which he curtailed funding for the project. Be that as it may, they started talking seriously about wireless power transmission only 90 years later, in 2007. And although it is still far from the moment when power lines completely disappear from the cityscape, pleasant little things like wireless charging of a mobile device are available now.

Progress crept up unnoticed

If we look through the archives of IT news at least two years ago, then in such collections we will find only rare reports that certain companies are developing wireless chargers, and not a word about finished products and solutions (except for basic principles and general schemes ). Today, wireless charging is no longer something super-original or conceptual. Such devices are being sold with might and main (for example, LG demonstrated its chargers at MWC 2013), tested for electric vehicles (Qualcomm is doing this) and even used in public places (for example, at some European railway stations). Moreover, there are already several standards for such transmission of electricity and several alliances promoting and developing them.

Similar coils are responsible for wireless charging of mobile devices, one of which is in the phone, and the other in the charger itself.

The most famous such standard is the Qi standard, developed by the Wireless Power Consortium, which includes such well-known companies as HTC, Huawei, LG Electronics, Motorola Mobility, Nokia, Samsung, Sony and about a hundred other organizations. This consortium was formed in 2008 with the aim of creating a universal charger for devices of various manufacturers and brands. In its work, the standard uses the principle of magnetic induction, when the base station consists of an induction coil, which creates an electromagnetic field when an alternating current is supplied from the network. In the device being charged, there is a similar coil that reacts to this field and is able to convert the energy received through it into direct current, which is used to charge the battery (you can learn more about the principle of operation on the consortium website http://www.wirelesspowerconsortium.com/what -we-do / how-it-works /). In addition, Qi supports a 2 kb / s data transfer protocol between chargers and rechargeable devices, which is used to transfer data on the required amount of charging and perform the required operation.

Today, many smartphones support wireless charging according to the Qi standard, and chargers are universal for all devices that support this standard.

Qi also has a serious competitor - the Power Matters Alliance, which includes AT&T, Duracell, Starbucks, PowerKiss and Powermat Technologies. These names are far from being in the first roles in the world of information technology (especially the Starbucks coffee chain, which is in an alliance due to the fact that it is going to introduce this technology everywhere in its establishments) - they specialize in energy issues. This alliance was formed not so long ago, in March 2012, within the framework of one of the programs of the IEEE (Institute of Electrical and Electronics Engineers). The PMA standard promoted by them works on the principle of mutual induction - a particular example of electromagnetic induction (which should not be confused with the magnetic induction used by Qi), when when the current in one of the conductors changes or when the relative position of the conductors changes, the magnetic flux changes through the circuit of the second, created a magnetic field generated by the current in the first conductor, which causes an electromotive force in the second conductor and (if the second conductor is closed) induction current. As with Qi, this current is then converted to DC and fed to the battery.

Well, do not forget about the Alliance for Wireless Power, which includes Samsung, Qualcomm, Ever Win Industries, Gill Industries, Peiker Acustic, SK Telecom, SanDisk, etc. This organization has not yet presented ready-made solutions, but among its goals , including - the development of charges that would work through non-metallic surfaces and which would not use coils.

One of the goals of the Alliance for Wireless Power is the ability to charge without being tied to a specific location and type of surface.

From all of the above, a simple conclusion can be drawn: in a year or two, most modern devices will be able to recharge without using traditional chargers. In the meantime, the power of wireless charging is mainly enough for smartphones, but for tablets and laptops such devices will also appear soon (the same Apple recently patented wireless charging for the iPad). This means that the problem of discharging devices will be almost completely solved - you put or put the device in a certain place, and even during operation it charges (or, depending on the power, discharges much more slowly). Over time, there is no doubt that the range of their action will expand (now it is necessary to use a special rug or stand on which the device lies, or it should be very close), and they will be ubiquitously installed in cars, trains and even, possibly, airplanes.

Well, and one more conclusion - most likely, it will not be possible to avoid another war of formats between different standards and alliances that promote them.

Will we get rid of the wires?

Wireless charging is a good thing, of course. But the powers that arise with it are sufficient only for the stated purposes. With the help of these technologies, it is not yet possible even to illuminate the house, let alone the work of large household appliances. Nevertheless, experiments on high-power wireless power transmission are underway and are based, among other things, on Tesla's materials. The scientist himself proposed to establish around the world (here, most likely, the developed countries at that time, which were much less than now), more than 30 transmitting and receiving stations that would combine the transmission of energy with radio broadcasting and directional wireless communication, which would allow getting rid of numerous high-voltage transmission lines and facilitating the interconnection of electrical generators on a global scale.

Today there are several methods for solving the problem of wireless power transmission, however, all of them so far allow to achieve globally insignificant results; it's not even about kilometers. Methods such as ultrasonic, laser and electromagnetic transmission have significant limitations (short distances, the need for direct visibility of transmitting devices, their size, and in the case of electromagnetic waves, very low efficiency and harm to health from a powerful field). Therefore, the most promising developments are associated with the use of a magnetic field, or rather, resonant magnetic interaction. One of them is WiTricity, developed by the WiTricity corporation, founded by MIT professor Marina Solyachich and a number of his colleagues.

So, in 2007, they managed to transmit a current with a power of 60 W over a distance of 2 m. It was enough for the glow of a light bulb, and the efficiency was 40%. But the indisputable advantage of the technology used was that it practically does not interact either with living things (the field strength, according to the authors, is 10 thousand times weaker than that which reigns in the core of the magnetic resonance imaging machine), or with medical equipment ( pacemakers, etc.), or with other radiation, which means that it will not interfere, for example, with the operation of the same Wi-Fi.

Most interestingly, the efficiency of the WiTricity system is influenced not only by the size, geometry and tuning of the coils, as well as the distance between them, but also by the number of consumers, and in a positive way. Two receiving devices, located at a distance of 1.6 to 2.7 m on either side of the transmitting "antenna", showed 10% better efficiency than separately - this solves the problem of connecting multiple devices to the same power source.

Wireless transmission for the delivery of electricity has the ability to deliver major advances in industry and applications relying on physical connector contact. It, in turn, can be unreliable and lead to failure. The transmission of wireless electricity was first demonstrated by Nikola Tesla in the 1890s. However, it is only in the past decade that technology has been used to the point that it offers real, tangible benefits for real-world applications. In particular, the development of resonant wireless power systems for the consumer electronics market has shown that induction charging provides new levels of convenience for millions of everyday devices.

The cardinality in question is widely known in many terms. Including inductive transmission, communication, resonant wireless network and the same voltage return. Each of these conditions essentially describes the same fundamental process. Wireless transmission of electrical power or power from a power source to a load voltage without connectors through an air gap. The basis is two coils - a transmitter and a receiver. The first is excited by an alternating current to generate a magnetic field, which in turn induces a voltage in the second.

How the system under consideration works

The fundamentals of wireless power involve the distribution of energy from a transmitter to a receiver through an oscillatory magnetic field. To achieve this, the direct current supplied by the power supply is converted to high frequency alternating current. With specially designed electronics built into the transmitter. The alternating current activates a coil of copper wire in the dispenser, which generates a magnetic field. When the second (receiving) winding is placed in close proximity. The magnetic field can induce an alternating current in the receiving coil. The electronics in the first device then converts the AC back to DC, which becomes a power draw.

Wireless power transmission circuit

The “mains” voltage is converted into an AC signal, which is then sent to the transmitter coil through an electronic circuit. Flowing through the dispenser winding induces a magnetic field. It, in turn, can propagate to the receiver coil, which is in relative proximity. The magnetic field then generates a current that flows through the winding of the receiving device. The process by which energy is distributed between the transmitting and receiving coils is also referred to as magnetic or resonant coupling. And it is achieved with both windings operating at the same frequency. The current flowing in the receiver coil is converted to DC by the receiver circuit. It can then be used to power the device.

What does resonance mean

The distance over which energy (or power) can be transmitted increases if the transmitter and receiver coils resonate at the same frequency. Just like a tuning fork oscillates at a certain height and can reach its maximum amplitude. It refers to the frequency with which an object naturally vibrates.

Benefits of wireless transmission

What are the benefits? Pros:

• Reduces costs associated with maintaining straight connectors (for example, in a traditional industrial slippery ring);
• more convenient for charging conventional electronic devices;
• secure transfer to applications that must remain hermetically sealed;
• electronics can be completely hidden, which reduces the risk of corrosion from elements such as oxygen and water;
• Reliable and consistent power supply to rotating, highly mobile industrial equipment;
• Provides reliable power delivery to mission-critical systems in wet, muddy and moving environments.

Regardless of the application, eliminating the physical connection provides a number of advantages over traditional cable power connectors.

The efficiency of the considered power transmission

The overall efficiency of a wireless power system is the most important factor in determining its performance. System performance measures the amount of power transferred between the power supply (that is, the wall outlet) and the receiving device. This, in turn, determines aspects such as charging speed and range.

Wireless communication systems vary according to their level of performance based on factors such as coil configuration and design, and transmission distance. A less efficient device will generate more emissions and result in less power passing through the receiver. Typically, wireless power transmission technologies for devices such as smartphones can achieve 70% performance.

How efficiency is measured

I mean, as the amount of power (in percentage) that is transferred from the power source to the receiving device. That is, wireless transmission of electricity to a smartphone with 80% efficiency means that 20% of the input power is lost between the wall outlet and the battery for the gadget being charged. The formula for measuring performance is: performance = DC outgoing divided by incoming, result multiplied by 100%.

Wireless ways of transmitting electricity

Power can propagate through the network in question over almost all non-metallic materials, including but not limited to. These are solids such as wood, plastic, textiles, glass and brick, as well as gases and liquids. When a metallic or electrically conductive material (that is, is placed in close proximity to an electromagnetic field, the object absorbs power from it and as a result heats up. This, in turn, affects the efficiency of the system. This is how induction cooking works, for example, inefficient power transmission from the hob creates heat for cooking.

To create a system for wireless transmission of electricity, it is necessary to return to the origins of the topic in question. Or, more precisely, to the successful scientist and inventor Nikola Tesla, who created and patented a generator capable of taking power without various materialistic conductors. So, for the implementation of a wireless system, it is necessary to assemble all the important elements and parts, as a result, a small device will be implemented. This is a device that creates a high voltage electric field in the air around it. At the same time, there is a small input power, it provides wireless transmission of energy at a distance.

One of the most important ways to transfer energy is inductive coupling. It is mainly used for the near field. It is characterized by the fact that when current flows through one wire, a voltage is induced at the ends of the other. Power transmission is accomplished by reciprocity between the two materials. A common example is a transformer. Microwave power transmission, as an idea, was developed by William Brown. The whole concept involves converting AC power to RF power and transmitting it in space and reusing it to AC power at the receiver. In this system, voltage is generated using microwave power sources. Such as the klystron. And this power is transmitted through a waveguide that protects against reflected power. And also a tuner that matches the impedance of the microwave source with other elements. The receiving section consists of an antenna. It adopts microwave power and impedance and filter matching circuitry. This receiving antenna, together with the rectifying device, can be a dipole. Corresponds to the output signal with a similar audible warning of the rectifier unit. The receiver unit also consists of a similar section made up of diodes that are used to convert the signal into a DC alert. This transmission system uses frequencies ranging from 2 GHz to 6 GHz.

Wireless transmission of electricity with the help of which the generator is realized using similar magnetic vibrations. The bottom line is that this device worked thanks to three transistors.

Using a laser beam to transmit power in the form of light energy, which is converted into electrical energy at the receiving end. The material itself is powered directly from sources such as the sun or any generator of electricity. And, accordingly, realizes high intensity focused light. The size and shape of the beam is determined by the set of optics. And this transmitted laser light is received by photovoltaic cells, which convert it into electrical signals. It usually uses fiber optic cables for transmission. As with the basic solar power system, the receiver used in laser-based propagation is an array of photovoltaic cells or a solar panel. They, in turn, can convert the incoherent into electricity.

Essential features of the device

The power of the Tesla coil lies in a process called electromagnetic induction. That is, the changing field creates potential. It makes a current flow. When electricity flows through a coil of wire, it generates a magnetic field that fills the area around the winding in a specific way. Unlike some other high voltage experiments, the Tesla coil has withstood many tests and trials. The process was quite laborious and lengthy, but the result was successful, and therefore successfully patented by the scientist. You can create such a coil if certain components are present. For implementation, you will need the following materials:

1. length 30 cm PVC (the more the better);
2. copper enameled wire (secondary wire);
3. birch board for the base;
4. 2222A transistor;
5. connection (primary) wire;
6. resistor 22 kOhm;
7. switches and connecting wires;
8. 9 volt battery.

Stages of Tesla device implementation

First, you need to place a small slot on the top of the pipe to wrap one end of the wire around. Wrap the coil slowly and carefully, taking care not to block the wires or create gaps. This step is the most difficult and tedious part, but taking the time will give you a very high quality and good coil. Every 20 or so turns, rings of masking tape are placed around the winding. They act as a barrier. In case the coil starts to unravel. When finished, wrap heavy tape around the top and bottom of the winding and spray it with 2 or 3 coats of enamel.

Then you need to connect the primary and secondary battery to the battery. After - turn on the transistor and resistor. The smaller winding is the main winding and the longer winding is the secondary winding. You can optionally install an aluminum sphere on top of the pipe. Alternatively, connect the open end of the secondary with the added one, which will act as an antenna. Care must be taken to create everything with great care so as not to touch the secondary device when turning on the power.

If you implement it yourself, there is a risk of fire. Flip the switch, place an incandescent light bulb next to the wireless power transmission device, and enjoy the light show.

Wireless transmission via solar power system

Traditional wired power distribution configurations typically require wiring between distributed devices and consumer units. This poses many constraints like the cost of the system cable costs. Loss incurred in transmission. And also waste in distribution. Only the resistance of the transmission line results in a loss of about 20-30% of the generated energy.

One of the most modern wireless power transmission systems is based on the transmission of solar energy using a microwave oven or a laser beam. The satellite is located in geostationary orbit and consists of photovoltaic cells. They convert sunlight into electrical current, which is used to power a microwave generator. And, accordingly, it realizes the power of microwaves. This voltage is transmitted using radio communications and received at the base station. It is a combination of antenna and rectifier. And converted back to electricity. Requires AC or DC power. The satellite can transmit up to 10 MW of radio frequency power.

If we talk about a DC distribution system, then even this is impossible. Since this requires a connector between the power supply and the device. There is such a picture: the system is completely devoid of wires, where you can get AC power in homes without any additional devices. Where it is possible to charge your mobile phone without having to physically connect to a jack. Of course, such a system is possible. And many modern researchers are trying to create something modernized, while studying the role of developing new methods of wireless transmission of electricity over a distance. Although, from the point of view of the economic component, it will not be entirely beneficial for the states if such devices are introduced everywhere and replace standard electricity with natural electricity.

Origins and examples of wireless systems

This concept is not really new. This whole idea was developed by Nicholas Tesla in 1893. When he developed a system of illuminating vacuum tubes using wireless transmission technique. It is impossible to imagine that the world would exist without various sources of charging, which are expressed in a material form. To make possible mobile phones, home robots, MP3 players, computers, laptops and other transportable gadgets that would charge themselves without any additional connections, freeing users from constant wires. Some of these devices may not even require a lot of items. The history of wireless energy transmission is quite rich, and, mainly, thanks to the developments of Tesla, Volta, etc. But, today it remains only data in physical science.

The basic principle is to convert AC power to DC voltage using rectifiers and filters. And then - to return to the original value at high frequency using inverters. This high-voltage, low-voltage AC power is then transferred from the primary transformer to the secondary transformer. Converted to DC voltage using rectifier, filter and regulator. The AC signal becomes direct due to the sound of the current. And also the use of the bridge rectifier section. The resulting DC signal is passed through a feedback coil that acts like a generator circuit. In this case, the transistor forces it to conduct into the primary converter in the direction from left to right. When a current passes through the feedback winding, a corresponding current flows to the primary of the transformer from right to left.

This is how the ultrasonic method of energy transmission works. The signal is generated through the primary converter for both half-periods of the AC warning. The sound frequency depends on the quantitative indicators of oscillations of the generator circuits. This AC signal appears on the secondary side of the transformer. And when it is connected to the primary converter of another object, the AC voltage is 25 kHz. A reading appears across it in the step-down transformer.

This AC voltage is equalized with a bridge rectifier. And then filtered and adjusted to get 5V output to drive the LED. The 12V output voltage from the capacitor is used to power the DC fan motor to operate. So, from the point of view of physics, the transmission of electricity is a fairly developed area. However, as practice shows, wireless systems are not fully developed and improved.

The law of the interaction of electric currents discovered by André Marie Ampere in 1820 laid the foundation for the further development of the science of electricity and magnetism. 11 years later, Michael Faraday experimentally established that a changing magnetic field generated by an electric current can induce an electric current in another conductor. So it was created.

In 1864, James Clerk Maxwell finally systematized Faraday's experimental data, giving them the form of exact mathematical equations, thanks to which the basis of classical electrodynamics was created, because these equations described the relationship of the electromagnetic field with electric currents and charges, and the existence of electromagnetic waves should have been a consequence of this.

In 1888, Heinrich Hertz experimentally confirmed the existence of electromagnetic waves predicted by Maxwell. His spark transmitter with a Rumkorf coil chopper could produce electromagnetic waves up to 0.5 gigahertz, which could be received by multiple receivers tuned into resonance with the transmitter.

The receivers could be located at a distance of up to 3 meters, and when a spark appeared in the transmitter, sparks appeared in the receivers. This is how first experiments on wireless transmission of electrical energy using electromagnetic waves.

In 1891, while studying alternating currents of high voltage and high frequency, he came to the conclusion that it is extremely important for specific purposes to select both the wavelength and the operating voltage of the transmitter, and it is not at all necessary to make the frequency too high.

The scientist notes that the lower limit of frequencies and voltages at which he managed to achieve the best results at that time was from 15,000 to 20,000 vibrations per second at a potential of 20,000 volts. Tesla received high frequency and high voltage current by applying an oscillatory discharge of a capacitor (see -). He noticed that this kind of electrical transmitter is suitable for both the production of light and the transmission of electricity for the production of light.

In the period from 1891 to 1894, the scientist repeatedly demonstrates wireless transmission, and the glow of vacuum tubes in a high-frequency electrostatic field, while noting that the energy of the electrostatic field is absorbed by the lamp, converted into light, and the energy of the electromagnetic field is used for electromagnetic induction in order to obtain a similar the result is mostly reflected, and only a small fraction of it is converted into light.

Even using resonance when transmitting with the help of an electromagnetic wave, a significant amount of electrical energy cannot be transmitted, the scientist argued. His goal during this period of work was the transmission of a large amount of electrical energy wirelessly.

Until 1897, in parallel with Tesla's work, studies of electromagnetic waves were conducted by Jagdish Boche in India, Alexander Popov in Russia, and Guglielmo Marconi in Italy.

Following Tesla's public lectures, Jagdish Boche spoke in November 1894 in Calcutta with a demonstration of the wireless transmission of electricity, where he ignited gunpowder, transmitting electrical energy over a distance.

After Boche, namely on April 25, 1895, Alexander Popov, using Morse code, transmitted the first radio message, and this date (May 7, new style) is now celebrated annually in Russia as "Radio Day".

In 1896, when Marconi arrived in Great Britain, he demonstrated his apparatus by transmitting a signal using Morse code over a distance of 1.5 kilometers from the roof of the post office building in London to another building. After that, he improved his invention and was able to transmit a signal along the Salisbury Plain already at a distance of 3 kilometers.

Tesla in 1896 successfully transmits and receives signals at a distance of about 48 kilometers between transmitter and receiver. However, none of the researchers has succeeded in transmitting a significant amount of electrical energy over a long distance.

Experimenting in Colorado Springs, in 1899, Tesla wrote: "The inconsistency of the induction method is enormous in comparison with the method of exciting the charge of earth and air." This will be the beginning of the scientist's research aimed at transmitting electricity over long distances without using wires. In January 1900, Tesla will make a note in his diary about the successful transfer of energy to a coil “carried out into the field”, from which the lamp was powered.

And the most grandiose success of the scientist will be the launch on June 15, 1903, of the Wardencliffe Tower on Long Island, designed to transmit electrical energy over considerable distances in large quantities without wires. The earthed secondary winding of the resonant transformer, topped with a copper spherical dome, had to excite the earth charge and conductive layers of air to become an element of the large resonant circuit.

So the scientist managed to power 200 lamps of 50 watts at a distance of about 40 kilometers from the transmitter. However, based on economic feasibility, financing of the project was stopped by Morgan, who from the very beginning invested money in the project in order to get wireless communication, and the transfer of free energy on an industrial scale over a distance, as a businessman, was categorically not satisfied with it. In 1917, the tower, designed for the wireless transmission of electrical energy, was destroyed.

Much later, in the period from 1961 to 1964, an expert in the field of microwave electronics William Brown experimented in the United States with paths for the transmission of energy by a microwave beam.

In 1964, he first tested a device (model of a helicopter) capable of receiving and using the energy of a microwave beam in the form of direct current, thanks to an antenna array consisting of half-wave dipoles, each of which is loaded with highly efficient Schottky diodes. Already by 1976, William Brown had carried out the transmission of a microwave beam of 30 kW power over a distance of 1.6 km with an efficiency exceeding 80%.

In 2007, a research group at the Massachusetts Institute of Technology led by Professor Marina Solyachich was able to wirelessly transmit energy over a distance of 2 meters. The transmitted power was sufficient to power a 60 watt light bulb.

Their technology (named) is based on the phenomenon of electromagnetic resonance. The transmitter and receiver are two copper coils with a diameter of 60 cm each resonating at the same frequency. The transmitter is connected to an energy source and the receiver is connected to an incandescent lamp. The loops are tuned to 10 MHz. The receiver in this case receives only 40-45% of the transmitted electricity.

Around the same time, Intel demonstrated a similar wireless power transmission technology.

In 2010, the Haier Group, a Chinese home appliance manufacturer, unveiled its unique product at CES 2010, a fully wireless LCD TV based on this technology.