CN210984490U

CN210984490U - Charging coil for high-power medium-long distance wireless transmission

Info

Publication number: CN210984490U
Application number: CN202020019403.1U
Authority: CN
Inventors: 李谦
Original assignee: Xi'an Dianche Fengyun Intelligent Technology Co ltd
Current assignee: Xi'an Dianche Fengyun Intelligent Technology Co ltd
Priority date: 2020-01-06
Filing date: 2020-01-06
Publication date: 2020-07-10
Anticipated expiration: 2030-01-06

Abstract

The utility model discloses a charging coil for high-power medium-distance wireless transmission, which comprises a circuit board, wherein the upper surface of the circuit board is provided with an upper layer circuit wiring A, the lower surface is provided with a lower layer circuit wiring B, and the upper layer circuit wiring A is formed by winding a surface-mounted copper wire which is sequentially and outwards wound to the edge of the circuit board from the center of the circuit board along the reverse/clockwise direction; the starting ends of the two wires penetrate through the circuit board to reach the lower surface of the circuit board, the starting end of one path of the surface-mounted copper wire is connected with the energy port through a surface-mounted copper wire with the same specification as the starting end of the other path of the surface-mounted copper wire after penetrating through the circuit board, and the tail end of the path of the surface-mounted copper wire is connected with the starting end of the other path of the surface-mounted copper wire through the surface-mounted copper wire to form a; the tail end of the other path of patch copper wire extends to the grounding port and is connected with the grounding port, and metal strips/pipes are fixed on the patch copper wires of the upper layer circuit wiring A and the lower layer circuit wiring B along the wires. The problem of charging coil heat dissipation capacity is high is solved.

Description

Charging coil for high-power medium-long distance wireless transmission

Technical Field

The utility model belongs to the technical field of wireless electromagnetism and energy, a remote wireless transmission's charging coil in high-power is related to.

Background

The wireless power transmission technology is derived from experiments performed by tesla in 1891: a wireless electromagnetic energy transmission path is formed by an electromagnetic emission source and an electromagnetic wave receiving end. This technology was improved and released by the institute of technology and technology of the Massachusetts in 2007 and received widespread attention. The electromagnetic technology most similar to the electromagnetic technology is the wireless data communication transmission technology (such as 3G, 4G, WiFi) which is well known and used by the public. The principle of wireless data transmission is similar to the principle of wireless power transmission, except that data transmission mainly uses far-field plane waves (far field), and wireless power transmission uses near-field electromagnetic waves (near field). With the prosperity and widespread use of mobile data terminals, wireless power delivery was renewed interest in the industry after 2000. In the technical research field, wireless power transmission is mainly divided into two development directions: the technology exploration in the advanced field based on laboratories; practical technology research and development focused on the consumer field.

At present, the technologies in the market application field are mainly divided into: 1. in theory, this is based on the principle of a conventional transformer, and the transmitter at both ends of the electromagnetic field is tuned to the resonant frequency band, so as to realize wireless inductive resonance transmission of electrical energy (System of transmission of electrical energy, US 645576A). 2. Transmission of longer-range wireless power by means of electromagnetic wave transmission. This technology mainly utilizes the array gain realized by the high-frequency antenna array, in the specific direction, improves the transmission efficiency between the antenna transmitting array and the receiving antenna, such as Wattup of PowerCast corporation; compared with the existing mature wireless data transmission technology, the wireless power transmission technology is still in the initial stage, the effective transmission distance is short (several centimeters), the circuit structure is complex, and the cost is high.

At present, the current wireless charging of cell-phone mainly uses QI technical standard: the mobile phone is composed of a winding coil and a magnetic core, so that the mobile phone is large in size, the transmission efficiency is 50-70%, and heat is easily generated in the mobile phone; the penetrability is low, resulting in a transmission distance of 3-5 mm, a charging power of 5-10 watts, and in addition, the transmitting coil and the receiving coil need to be strictly aligned. The application prospect of wireless charging in mobile phone panels, wearable equipment and the like is severely restricted by various defects of the technology.

Due to the working principle, the electromagnetic induction mode used by the QI technology must use the combined action of the copper wire coil and the magnetic core to improve the transmission efficiency, so that the QI charging module inside the mobile phone is large in volume and high in heat dissipation. To the narrow and small equipment in spaces such as cell-phone, flat board, wearable equipment, it must be enough little to be located the inside wireless receiving module volume that charges of equipment, guarantees high transmission efficiency. With the increasingly powerful functions of mobile phone tablet wearable devices, the transmission power also needs to be increased to meet the demand of quick charging. In order to improve the user experience of the product, the requirements of long transmission distance, low heat dissipation capacity and the like also need to be comprehensively considered. These all need to be designed using entirely new concepts.

Disclosure of Invention

An object of the embodiment of the utility model is to provide a remote wireless transmission's charging coil in high-power to solve current charging coil module bulky, transmission efficiency and transmission power low, transmission distance is short, the higher scheduling problem of heat dissipation capacity.

The embodiment of the utility model adopts the technical proposal that the charging coil for high-power medium-distance wireless transmission comprises a circuit board, wherein the upper surface of the circuit board is provided with an upper layer circuit wiring A, and the lower surface of the circuit board is provided with a lower layer circuit wiring B; the upper layer circuit wiring A is formed by winding a patch copper wire which is wound from the center of the upper surface of the circuit board along the anticlockwise direction or the clockwise direction and is wound to the edge of one side of the surface of the circuit board from two wires in sequence; the starting ends of the two wires of the upper layer circuit wiring A penetrate through the circuit board to reach the lower surface of the circuit board, the starting end of one path of patch copper wire is connected with the energy port through a patch copper wire with the same specification and a capacitor module, and the tail end of the path of patch copper wire penetrates through the circuit board and then is connected with the starting end of the other path of patch copper wire through a patch copper wire with the same specification, so that a lower layer circuit wiring B is formed; the tail end of the other path of patch copper wire extends to the grounding port and is connected with the grounding port; and metal strips or metal tubes are fixed on the patch copper wires of the upper layer circuit wiring A and the lower layer circuit wiring B along the lines.

Further, the width of the metal strip or the outer diameter of the metal tube is equal to the width of the patch copper wires of the upper-layer circuit wiring A and the lower-layer circuit wiring B;

The wire spacing of the metal strips or the metal tubes is equal to the wire spacing of the upper-layer circuit wiring A and the lower-layer circuit wiring B;

The metal pipe adopts a copper pipe, and the metal strip adopts a copper strip.

Furthermore, the line width of the upper layer circuit wiring A and the lower layer circuit wiring B are both 2 +/-1.5 mm, the line spacing is both 3.25 +/-2 mm, and the line corners are arranged in an arc shape.

Furthermore, the circuit board is a hard or flexible plate with a dielectric constant less than 5 and a thickness less than 5mm, and the length and the width of the circuit board are both less than 15 cm.

Furthermore, the metal tubes welded to the upper layer circuit wiring a and the lower layer circuit wiring B are filled with a cooling liquid having a poor conductivity and a high impedance, and the metal tubes welded to the upper layer circuit wiring a are connected to the metal tubes welded to the lower layer circuit wiring B through the circuit board.

Further, the coolant with the low conductivity and the high impedance is supplied by an external heat sink connected to the transmission coil to form a closed loop;

The external heat dissipation device is composed of a water pump, a heat radiator, a water inlet pipe, a first water outlet pipe and a second water outlet pipe, a cooling liquid outlet of the water pump is connected with a cooling liquid inlet of the coil through the water inlet pipe, a cooling liquid outlet of the coil is connected with the cooling liquid inlet of the heat radiator through the first water outlet pipe for heat dissipation, and a cooling liquid outlet of the heat radiator is connected with the cooling liquid inlet of the water pump through the second water outlet pipe.

Furthermore, a cooling liquid inlet of the coil is a metal pipe orifice at the joint of the upper-layer circuit wiring A and the grounding port, and a cooling liquid outlet of the coil is a metal pipe orifice at the joint of a pin of the capacitor module, which is not connected with the energy port, and the lower-layer circuit wiring B; or the cooling liquid inlet of the coil is a metal pipe orifice at the joint of the pin of the capacitor module, which is not connected with the energy port, and the lower-layer circuit wiring B, and the cooling liquid outlet of the coil is a metal pipe orifice at the joint of the upper-layer circuit wiring A and the grounding port;

The water pump adopts a micro pump;

The cooling liquid with poor conductivity and high impedance adopts liquid nitrogen;

The water inlet pipe, the first water outlet pipe and the second water outlet pipe are all rubber hoses, and the inner diameter of each rubber hose is smaller than or equal to the inner diameter of the metal pipe on the transmission coil.

The embodiment of the utility model has the advantages that, in order to reduce the heating problem of high transmission power and obtain higher transmission efficiency, the metal strip or the metal tube is arranged on the surface-mounted copper wire, and the thickness of the metal strip or the metal tube meets the skin depth, the outer layer of the metal strip or the metal tube transmits energy or data, the inner part radiates heat, the heating speed is effectively reduced, the temperature saturation critical value is reduced, and the charging is rapidly completed before the over-temperature value; simultaneously, the increment of metal can produce stronger magnetic field, the heat conductivity of charging coil has both been increased, the transmission efficiency of coil has been promoted again, can carry out power more than or equal to 500W, transmission distance is at 1mm ~10 cm's energy transmission, and the length and the width of circuit board are less than 15cm, transmission efficiency reaches 90~95%, effectively solved current charging coil module bulky, transmission efficiency and transmission power are low, transmission distance is short, the heat dissipation capacity is higher scheduling problem. And for the energy transmission with the power of more than 500W, a metal tube is arranged on the surface-mounted copper wire, cooling liquid with poor conductivity and high impedance flows in the metal tube, and under the action of an external heat circulating device, the cooling liquid guides the heat energy on the metal tube to the outside to effectively dissipate the heat of the high-power charging coil. Just the utility model discloses the coil is when improving coupling transmission's efficiency, and does not influence circuit design parameter.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is the utility model discloses charging coil's structure schematic diagram.

Fig. 2 is the utility model discloses upper circuit wiring A schematic diagram of charging coil.

Fig. 3 is the utility model discloses simulation effect picture of charging coil.

Fig. 4 is a diagram of the relationship between indexes of the transmission coil.

Fig. 5 is a graph comparing transmission efficiency of a coil according to an embodiment of the present invention with a coil without a metal strip or a metal tube.

Fig. 6(a) is a schematic diagram of the magnetic field distribution of a coil that is not wired with metal strips or tubes.

Fig. 6(b) is a schematic diagram of the magnetic field distribution of the coil according to the embodiment of the present invention.

Fig. 7 is a block diagram of an external heat sink according to an embodiment of the present invention.

In the figure, 1 is a circuit board, 2 is an upper layer circuit wiring A, 3 is a through hole, 4 is a lower layer circuit wiring B, 5 is an energy port, 6 is a grounding port, 7 is a capacitor module, 11 is an upper layer first through hole, 12 is an upper layer second through hole, 13 is an upper layer third through hole, 21 is a lower layer first through hole, 22 is a lower layer second through hole, 23 is a lower layer third through hole, 8 is a water pump, 9 is a radiator, 10 is a water inlet pipe, 14 is a first water outlet pipe, and 15 is a second water outlet pipe.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

The charging coil structure for high-power medium and long-distance transmission is shown in figures 1-2 and comprises a circuit board 1, wherein an upper layer circuit wiring A2 is arranged on the upper surface of the circuit board 1, and a lower layer circuit wiring B4 is arranged on the lower surface of the circuit board 1; the upper layer circuit wiring A2 is formed by winding a patch copper wire which is sequentially wound from the center of the upper surface of the circuit board 1 to the edge of one side of the surface of the circuit board 1 outwards along a counterclockwise direction; the starting ends of the two wires of the upper-layer circuit wiring A2 penetrate through the circuit board 1 and reach the lower surface of the circuit board 1, the starting end of one path of patch copper wire is connected with the energy port 5 through a patch copper wire with the same specification as the starting end of the other path of patch copper wire through a capacitor module 7, and the tail end of the one path of patch copper wire penetrates through the circuit board 1 and is connected with the starting end of the other path of patch copper wire through a patch copper wire with the same specification as the starting end of the other path of patch copper wire, so that a; the end of the other patch copper wire extends to the ground port 6 and is connected with the ground port 6. Specifically, the tail end of one copper wire in the double wires reaches the lower surface of the circuit board 1 through a through hole 3 penetrating through the upper surface and the lower surface of the circuit board 1, one end, located on the upper surface of the circuit board 1, of the through hole 3 is an upper-layer first through hole 11, one end, located on the lower surface of the circuit board 1, of the through hole is a lower-layer first through hole 21, and one copper wire passes through the through hole 3 and reaches the lower-layer first through hole 21 on the lower surface of the. The upper surface center of circuit board 1 is equipped with upper second through-hole 12 and upper third through-hole 13, and the lower surface center of circuit board 1 is equipped with lower floor's second through-hole 22 and lower floor's third through-hole 23, and upper second through-hole 12 is link up with lower floor's second through-hole 22 perpendicularly, and upper third through-hole 13 is link up with lower floor's third through-hole 23 perpendicularly. The starting end of one path of patch copper wire in the double lines of the upper layer circuit wiring A2 sequentially passes through the upper layer second through hole 12 and the lower layer second through hole 22, and is connected with the starting end of one path of patch copper wire positioned on the lower surface of the circuit board 1 through the through hole 3 through the patch copper wire with the same specification. The initiating terminal of another way paster copper line is in proper order through upper third through-hole 13 and lower floor's third through-hole 23 in the double-line to be connected with the one end of capacitor module 7 through the paster copper line of the same specification, the other end of capacitor module 7 is through the paster copper line connection energy port 5 of the same specification, and energy port 5 connects outside cable. And metal strips or metal tubes are fixed to the patch copper wires of the upper layer circuit wiring a2 and the lower layer circuit wiring B4 along the wires.

In this embodiment, the widths and the line pitches of the patch copper lines of the upper circuit wiring a2 and the lower circuit wiring B4 are equal, and the widths and the line pitches are 2 ± 1.5mm and 3.25 ± 2mm, respectively. The outer diameter/width of the copper strip and the line spacing of the copper pipe are equal to those of the surface-mounted copper wire. Additionally, the embodiment of the utility model provides an all turnings of charging coil all adopt the setting of arc shape, and the angle that the bent angle was bent promptly is 30~85, guarantees transmission efficiency. This is because the transmission efficiency is reduced by 10-15% when the right angle is adopted at the corner of the copper pipe/copper bar. The circuit board 1 is a hard or flexible plate with a dielectric constant less than 5 and a thickness less than 5mm, and the length and the width of the plate are both less than 15 cm. The capacitor module 7 can mount various capacitor banks packaged as 0402, 0603, 0805, 1206, 1812, 2010, 2225, 2512 according to the capacitor bank size.

This embodiment dispels the heat when improving transmission efficiency for the time of arriving the excess temperature value lengthens, guarantees to accomplish fast before the excess temperature value and charges. Copper pipes with the diameter of 3mm and the thickness of 0.8mm (namely the inner diameter of 2.2 mm) are welded on patch copper wires of an upper layer circuit wiring A2 and a lower layer circuit wiring B4 of a circuit board 1, the obtained coil completes the charging of a 48V battery with the capacity of 10Ah within 2 hours under the energy transmission power of 250W, the temperature of the coil does not exceed the standard temperature index of products in the general consumer market by 80 ℃, and the energy transmission power of the coil, namely the thickness of the copper pipe or the thickness of a copper bar, can reach 500W when the thickness of the coil is 2.5-3 mm.

When energy transmission power more than or equal to 500W, the system must have the excess temperature problem, for solving this problem, the embodiment of the utility model provides an on adopting the copper pipe to carry out the radiating basis of energy transmission, when increasing copper pipe external diameter and thickness, the coolant liquid (like the liquid nitrogen) that the interior circulation conductivity is poor, the impedance is high of welded copper pipe on upper circuit wiring A2 and lower floor circuit wiring B4, just welded copper pipe passes welded copper union coupling on circuit board 1 and lower floor circuit wiring B4 on the upper circuit wiring A2. The cooling liquid with poor conductivity and high impedance is supplied by an external heat sink connected with the charging coil to form a closed loop. As shown in fig. 7, the external heat dissipation device is composed of a water pump 8, a heat sink 9, a water inlet pipe 10, a first water outlet pipe 14 and a second water outlet pipe 15, a coolant outlet of the water pump 8 is connected with a coolant inlet of the coil through the water inlet pipe 10, a coolant outlet of the coil is connected with a coolant inlet of the heat sink 9 through the first water outlet pipe 14 for heat dissipation, and a coolant outlet of the heat sink 9 is connected with a coolant inlet of the water pump 8 through the second water outlet pipe 15. A cooling liquid inlet of the coil is a copper pipe orifice at the joint of the upper-layer circuit wiring A2 and the grounding port 6, and a cooling liquid outlet of the coil is a copper pipe orifice at the joint of a pin of the capacitor module 7, which is not connected with the energy port 5, and the lower-layer circuit wiring B4; or the cooling liquid inlet of the coil is a copper pipe orifice at the joint of the pin of the capacitor module 7, which is not connected with the energy port 5, and the lower-layer circuit wiring B4, and the cooling liquid outlet of the coil is a copper pipe orifice at the joint of the upper-layer circuit wiring A2 and the grounding port 6. The water pump 8 adopts a micro pump, the water inlet pipe 10, the first water outlet pipe 14 and the second water outlet pipe 15 all adopt rubber hoses, and the inner diameter of each rubber hose is smaller than or equal to the inner diameter of the metal pipe on the transmission coil. Through the water pump 8, the radiator 9, the cooling liquid with poor conductivity or high impedance and the formed closed loop, the heat exchange and the heat dissipation of the copper pipe are realized, and the cyclic utilization of the cooling liquid is realized.

The embodiment of the utility model provides a can shorten the paster copper line between capacitor module 7 and the energy port 5 to capacitor module 7 closes on energy port 5, begins to form coolant liquid circulation circuit promptly to the copper pipe end of 6 departments of ground connection port by the copper pipe of capacitor module 7 top so, and the temperature influence of the paster copper line (being close to energy port 5) that has shortened is by infinitely holding down, consequently can neglected.

The embodiment of the utility model provides an utilize the water delivery function of copper pipe ingeniously, let the copper pipe coil of small-size big wattage can use general water-cooled equipment. The water cooling device uses a soft rubber water pipe to fill cooling liquid into the copper pipe on the hot point, and the cooling liquid circulates for a circle to pass through the soft rubber water pipe to reach the radiator 9 at the outer head so as to take away heat energy. In this case, the high-frequency current is passed through the skin surface while selecting a physical surface having a low impedance, and therefore does not adversely affect the performance of the high-frequency coil. Therefore, the heat dissipation method of the welded copper pipe and the cooling liquid can effectively solve the over-temperature problem of a system with the working power of 500 watts or more and several ten thousand watts, such as the over-temperature problem of a charging system of an electric bus (with the power of 100-150 kW), an electric automobile (with the power of 20-50 kW) and the like.

The coil wiring of the present embodiment is performed according to the following steps:

Step S1, simulating, adjusting and optimizing physical parameters such as line width and line spacing of the upper layer circuit wiring a2 and the lower layer circuit wiring B4, and corner angles set by arc shapes at corners, and determining the optimal physical parameters of the upper layer circuit wiring a2 and the lower layer circuit wiring B4. The method comprises the steps of etching an upper-layer circuit wiring A2 and a lower-layer circuit wiring B4 on a circuit board 1 according to certain physical parameters to form a patch copper wire coil, measuring the transmission efficiency of the patch copper wire coil, then performing simulation, adjustment and optimization on the physical parameters of the upper-layer circuit wiring A2 and the lower-layer circuit wiring B4 by adopting simulation software, preparing and forming the optimized patch copper wire coil according to the optimized physical parameters of the upper-layer circuit wiring A2 and the lower-layer circuit wiring B4, measuring the transmission efficiency, and circularly performing simulation optimization, etching and measurement on the transmission efficiency until the physical parameters of an upper-layer circuit wiring A2 and a lower-layer circuit wiring B4 which enable the transmission efficiency of the patch copper wire coil to be the maximum are obtained and used as the optimal physical parameters of the upper-layer circuit wiring A2 and the lower-layer circuit wiring.

Step S2, etching the upper layer circuit wiring a2 and the lower layer circuit wiring B4 on the circuit board 1 according to the optimum physical parameters of the upper layer circuit wiring a2 and the lower layer circuit wiring B4, and then soldering a metal bar or a metal tube along its route on the etched patch copper wires of the upper layer circuit wiring a2 and the lower layer circuit wiring B4. Specifically, a metal strip or a metal tube is directly welded on a patch copper wire along the circuit according to the wires of an upper-layer circuit wiring A2 and a lower-layer circuit wiring B4 etched on the circuit board 1 by adopting the auxiliary fixation of a mold.

Adopt the mould to assist fixedly, according to the wiring of paster copper line coil directly welding copper pipe or copper bar on paster copper line coil, needn't fine setting again, just can possess the good, efficient and the far away characteristic of transmission distance of heat dissipation, coil inductance value must can reach the degree of resonance coupling, through optimizing the range of this coil inductance value of timing at 1-1500pf for at interval 1mm ~10cm Within a certain distance, the coil only needs electric capacity module 7 can be in effective design distance in 6.78MHz production high efficiency electromagnetic resonance coupling, and the coupling effect is as shown in fig. 3, is the utility model discloses the simulation result picture of charging coil, wherein about the transmission coefficient who has 0.8MHz bandwidth is 97.4%, and transmission efficiency is 97.4% ²= 95%; the transmission coefficient of the 1.3MHz bandwidth is 94.8%, and the transmission efficiency is 94.8% ²= 90%; the transmission coefficient of the 1.5MHz bandwidth is 92.2 percent, and the transmission efficiency is 92.2 percent ²=85%, no other design currently achieves such a wide frequency high efficiency energy transfer. In fig. 3, a curve S1,1 is a variation curve of the reflection coefficient of the transmitting coil port with frequency, a curve S2,2 is a variation curve of the reflection coefficient of the receiving coil port with frequency, a curve S1,2 is a variation curve of the reverse transmission coefficient with frequency, and a curve S2,1 is a variation curve of the forward transmission coefficient with frequency.

The outer diameter of the metal tube or the width of the metal strip is equal to the width of the patch copper wire on the circuit board 1, the thickness of the metal strip needs to be guaranteed to be outside the skin depth range, namely the thickness of the metal strip is larger than the skin depth, and the system can be quickly charged before the over-temperature value through proper thickness design and adjustment.

The transmission distance is related to the size of the coil and the strength of the magnetic field, and under the same frequency, area and transmission power, the electromagnetic field is strong, so that the coupling conversion can be effectively carried out, and the transmission efficiency is high; meanwhile, the coil with a large area has a large magnetic field and a corresponding distance is long, so that the coil with a small area and a long transmission distance is difficult. This application coil length, wide all are less than 15cm, and in the distance of interval 1mm ~10cm, the coil only needs capacitor module 7 can produce high efficiency electromagnetic resonance coupling in 6.78MHz in effective design distance, and the effect is seen in figure 3, and present battery charging outfit's transmission efficiency generally 70%, the best can reach 85%, and the charge coil transmission efficiency of this embodiment reaches 90~ 95%.

Fig. 4 depicts the relationship between the transmission coil and its electromagnetic and transmission characteristics, where a represents power VS temperature, b represents multilayer design VS temperature, c represents dimension VS efficiency, d represents distance VS efficiency, e represents frequency VS dimension, f represents frequency VS efficiency, and g represents all index VS cost. As can be seen from fig. 4, the higher the transmission power, the higher the coil temperature; the more the number of coil layers is, the lower the surface temperature is; the larger the coil size, the higher the transmission efficiency; the farther the distance between the coils is, the lower the transmission efficiency is, the higher the working frequency is, the smaller the coil size is, and the working frequency and the transmission efficiency are not directly related; the higher each index is, the higher the cost is. Therefore, it can be seen that many indexes (cost, efficiency, difficulty, size, distance, etc.) are contradictory, and are mutually restricted, and it is very difficult to achieve better balance between each index, but the embodiment of the utility model provides an adopt simple and easy processing to just obtain ideal effect, and low cost.

Fig. 5 is a transmission efficiency contrast diagram of the coil of the embodiment of the present invention and the coil that does not adopt metal strip or metal tube wiring, and as can be seen from fig. 5, between 6-7.1 MHz (containing 6.78 MHz), the utility model discloses the coil transmission efficiency of the embodiment is greater than the coil that does not adopt metal strip or metal tube wiring. Fig. 6(a) is a schematic view of the magnetic field distribution of the coil without the metal strip or the metal tube, and fig. 6(b) is a schematic view of the magnetic field distribution of the coil according to the embodiment of the present invention, which can be seen from fig. 6(a) - (b), the magnetic field distribution of the coil according to the embodiment of the present invention is more dense, stable and uniform. And the utility model discloses the electromagnetic energy is restricted in near the coil strictly, especially between the coil, especially the core region, and this is also the utility model discloses a special point, through measuring, under 15cm distance, the electromagnetic energy is restricted strictly.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

Claims

1. The charging coil for high-power medium-and-long-distance wireless transmission is characterized by comprising a circuit board (1), wherein an upper layer circuit wiring A (2) is arranged on the upper surface of the circuit board (1), and a lower layer circuit wiring B (4) is arranged on the lower surface of the circuit board (1); the upper layer circuit wiring A (2) is formed by winding a patch copper wire which sequentially surrounds from the center of the upper surface of the circuit board (1) to the edge of one side of the surface of the circuit board (1) outwards along a counter-clockwise or clockwise direction; the starting ends of the double wires of the upper layer circuit wiring A (2) penetrate through the circuit board (1) to reach the lower surface of the circuit board (1), the starting end of one path of patch copper wire is connected with the energy port (5) through a patch copper wire with the same specification as the circuit board, and the tail end of the path of patch copper wire penetrates through the circuit board (1) and is connected with the starting end of the other path of patch copper wire through a patch copper wire with the same specification as the circuit board to form a lower layer circuit wiring B (4); the tail end of the other path of patch copper wire extends to the grounding port (6) and is connected with the grounding port (6); and metal strips or metal tubes are fixed on the patch copper wires of the upper layer circuit wiring A (2) and the lower layer circuit wiring B (4) along the circuits.

2. The charging coil for high-power medium-and-long-distance wireless transmission according to claim 1, wherein the width of the metal strip or the outer diameter of the metal tube is equal to the width of the patch copper wires of the upper-layer circuit wiring A (2) and the lower-layer circuit wiring B (4);

The wire spacing of the metal strips or the metal tubes is equal to the wire spacing of the upper layer circuit wiring A (2) and the lower layer circuit wiring B (4);

The metal pipe adopts a copper pipe, and the metal strip adopts a copper strip.

3. The high-power medium-and-long-distance wireless transmission charging coil according to claim 1, wherein the line width and the line distance of the upper layer circuit wiring A (2) and the lower layer circuit wiring B (4) are both 2 ± 1.5mm and 3.25 ± 2mm, and the line turns are arranged in an arc shape.

4. High power medium-long distance wireless transmission charging coil according to claim 1, characterized in that the circuit board (1) is a hard or flexible sheet material with a dielectric constant less than 5 and a thickness less than 5mm, and its length and width are both less than 15 cm.

5. The charging coil for high-power medium-and long-distance wireless transmission according to claim 1, wherein a cooling liquid with poor conductivity and high impedance flows through the metal tubes welded to the upper circuit wiring A (2) and the lower circuit wiring B (4), and the metal tubes welded to the upper circuit wiring A (2) are connected to the metal tubes welded to the lower circuit wiring B (4) through the circuit board (1).

6. The high power medium-long distance wireless transmission charging coil according to claim 5, wherein the cooling liquid with low conductivity and high impedance is supplied by an external heat sink connected with the transmission coil to form a closed loop;

The external heat dissipation device is composed of a water pump (8), a radiator (9), a water inlet pipe (10), a first water outlet pipe (14) and a second water outlet pipe (15), a coolant outlet of the water pump (8) is connected with a coolant inlet of the coil through the water inlet pipe (10), a coolant outlet of the coil is connected with a coolant inlet of the radiator (9) through the first water outlet pipe (14) for heat dissipation, and a coolant outlet of the radiator (9) is connected with a coolant inlet of the water pump (8) through the second water outlet pipe (15).

7. The charging coil for high-power medium-and-long-distance wireless transmission according to claim 6, wherein the cooling liquid inlet of the coil is a metal pipe orifice at the joint of the upper-layer circuit wiring A (2) and the grounding port (6), and the cooling liquid outlet of the coil is a metal pipe orifice at the joint of the pin of the capacitor module (7) which is not connected with the energy source port (5) and the lower-layer circuit wiring B (4);

Or the cooling liquid inlet of the coil is a metal pipe orifice at the joint of a pin of the capacitor module (7) which is not connected with the energy port (5) and the lower-layer circuit wiring B (4), and the cooling liquid outlet of the coil is a metal pipe orifice at the joint of the upper-layer circuit wiring A (2) and the grounding port (6); the water pump (8) adopts a micro pump; the cooling liquid with poor conductivity and high impedance adopts liquid nitrogen;

The water inlet pipe (10), the first water outlet pipe (14) and the second water outlet pipe (15) are all rubber hoses, and the inner diameter of each rubber hose is smaller than or equal to the inner diameter of the metal pipe on the transmission coil.