Wireless energy transmission device

Abstract

The invention relates to the technical field of energy transmission, and discloses a wireless energy transmission device. The device comprises a transmitting device and a receiving circuit, the transmitting device comprises a transmitting circuit and a decoupling circuit, and the transmitting circuit and the decoupling circuit are arranged in parallel and are both connected with an alternating current power supply. Before wireless energy transmission between a transmitting coil and a receiving coil, decoupling is carried out through a cross-shaped decoupling coil, a uniform magnetic field is established, and the size parameter of the receiving coil is consistent with that of the transmitting coil, so that the size parameter of the receiving coil is far smaller than that of a plurality of coils for decoupling the uniform magnetic field; even if the receiving coil deviates from the central point of a certain transmitting coil, the energy which can be received cannot be greatly attenuated, so that the scheme of the invention can be suitable for various application scenes, and can still keep relatively high energy transmission efficiency under a certain deviation distance.

Description

Technical Field

[0001] The present application relates to the technical field of energy transmission, and in particular, to a wireless energy transmission device. Background Art

[0002] Several existing schemes for wireless energy transmission using electromagnetic waves all use the near field of the electromagnetic field to achieve the effect of radiating electromagnetic waves, but they all have their own problems. Although electromagnetic induction and electric coupling wireless energy transmission have the advantages of fast frequency conversion speed and high efficiency, the transmission distance between the transmitting coil and the receiving coil is very short. The transmission distance d is relatively small relative to the coil size a. For magnetically coupled resonant wireless energy transmission, the distance d≈a, that is, the transmission distance is approximately equal to the coil size.

[0003] For laser coupling and microwave radiation wireless energy transmission, they use the far field of the electromagnetic field for radiation. Although they both have the advantages of strong directionality and long enough radiation distance. However, the electromagnetic wave frequencies they use are generally high (the microwave radiation frequency is 300MHz-300GHz, and the laser radiation frequency is 3.9×10^14Hz-7.7×10^14Hz). Since high-frequency lines have extremely strict requirements on signals and the construction of the environment, the systems built by these two solutions have extremely high requirements on the accuracy of internal device use and circuit application. The design difficulty of the system is also exponentially higher than that of the systems of several solutions using near-field radiation, and the cost also increases exponentially. Therefore, the wireless energy transmission system realized by magnetic coupling resonant technology has the advantages of simple system and low device design requirements compared with laser coupling and microwave radiation, and can also increase the distance of energy transmission to a certain extent.

[0004] The general magnetic coupling resonance technology also has corresponding disadvantages. The biggest disadvantage is the extremely high requirement for the alignment between the transmitting coil and the receiving coil. Usually, the maximum efficiency of energy transmission between the transmitting coil and the receiving coil is when the centers of the two coils are completely aligned. Once the deviation occurs, the energy transmission efficiency will be drastically attenuated. Summary of the invention

[0005] The present application provides a wireless energy transmission device to solve one or more technical problems existing in the prior art, and at least provide a beneficial choice or create conditions.

[0006] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0007] According to one aspect of an embodiment of the present application, a wireless energy transmission device is provided, comprising a transmitting device and a receiving circuit; the transmitting device comprises a transmitting circuit and a decoupling circuit, the transmitting circuit and the decoupling circuit are arranged in parallel, and both are connected to an AC power supply;

[0008] The transmitting circuit includes four transmitting coils, the decoupling circuit includes a cross-shaped decoupling coil, and the four transmitting coils and the cross-shaped decoupling coil form a decoupled uniform magnetic field multi-coil;

[0009] The receiving circuit comprises a receiving coil, wherein the receiving coil is coupled to each of the transmitting coils, and the size parameters of the receiving coil are consistent with the size parameters of the transmitting coil;

[0010] The design of the decoupled uniform magnetic field multi-coil can be specifically as follows: the four transmitting coils are arranged in a square matrix; the cross-shaped decoupling coil includes a base and four extensions, the base is connected to the four extensions, and the base is arranged at the center of the matrix array; the four extensions are respectively arranged between each two adjacent transmitting coils;

[0011] The coil winding direction of the four transmitting coils is a first preset direction, the coil winding direction of the cross-shaped decoupling coil is a second preset direction, and the first preset direction is opposite to the second preset direction.

[0012] In one embodiment of the present application, based on the aforementioned scheme, the transmitting coil is obtained by winding a first preset antenna in a square with a first preset number of turns, the distance between each adjacent turn is 2 mm, the thickness of the first preset antenna is 2 mm, the side length of the transmitting coil is 82 mm, and the distance between the transmitting circuit and the receiving circuit is 80 mm to 82 mm.

[0013] In one embodiment of the present application, based on the above solution, the distance between the extension portion and two adjacent transmitting coils is 4 mm, the length of the extension portion is 30 mm, and the width of the extension portion is 86 mm.

[0014] In one embodiment of the present application, based on the aforementioned scheme, the cross-shaped decoupling coil is obtained by cross-winding a second preset number of turns of a second preset antenna, the distance between each adjacent turns is 2 mm, and the thickness of the second preset antenna is 2 mm.

[0015] In one embodiment of the present application, based on the aforementioned scheme, the transmitting circuit further includes a first inductor, a first capacitor, a second capacitor and a first resistor, and the output end of the AC power supply, the first inductor, the first capacitor, the first resistor, the transmitting coil and the input end of the AC power supply are connected in sequence; the second capacitor is connected in parallel with the transmitting coil and is connected to the first inductor, the first capacitor and the input end of the AC power supply.

[0016] In one embodiment of the present application, based on the above solution, the resonance equation of the transmitting coil is specifically:

[0017]

[0018] In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R Tn For the first resistor, C Tn is the first capacitor, C Tn_2 is the second capacitor, L Tn is the first inductor, L Tn1

[0019] is the self-inductance of the transmitting coil.

[0020] In one embodiment of the present application, based on the above-mentioned scheme, the decoupling circuit further includes a second inductor, a third capacitor, a fourth capacitor and a second resistor, and the output end of the AC power supply, the second inductor, the third capacitor, the second resistor, the cross decoupling coil and the input end of the AC power supply are connected in sequence; the fourth capacitor is connected in parallel with the transmitting coil and is connected to the second inductor, the third capacitor and the input end of the AC power supply.

[0021] In one embodiment of the present application, based on the above solution, the resonance equation of the cross-shaped decoupling coil is specifically:

[0022]

[0023] In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R Tre For the second resistor, C Tre is the third capacitor, C Tre_2 is the fourth capacitor, L Tre For the second inductor, L Tre1 is the self-inductance of the cross-shaped decoupling coil.

[0024] In one embodiment of the present application, based on the aforementioned scheme, the receiving circuit also includes a third resistor, a fourth resistor, a third inductor, a fifth capacitor and a sixth capacitor; the receiving coil, the third resistor, the fifth capacitor, the third inductor, and the fourth resistor are connected in sequence to form a loop, and the sixth capacitor is connected in parallel with the fourth resistor and is connected to the fifth capacitor, the third inductor, the fourth resistor and the receiving coil.

[0025] In one embodiment of the present application, based on the above solution, the resonance equation of the receiving coil is specifically:

[0026]

[0027] In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R R is the third resistor, R L is the fourth resistor, C R is the fifth capacitor, C R_2 is the sixth capacitor, L R is the receiving coil self-inductance, L R1 is the third inductor.

[0028] Beneficial effects of the present application: The present application designs a decoupled uniform magnetic field multi-coil, wherein the four transmitting coils are arranged in a square matrix; the cross-shaped decoupling coil includes a base and four extensions, the base is connected to the four extensions, and the base is arranged at the center of the matrix array; the four extensions are respectively arranged between each two adjacent transmitting coils; the coil winding direction of the four transmitting coils is a first preset direction, and the coil winding direction of the cross-shaped decoupling coil is a second preset direction, and the first preset direction is opposite to the second preset direction. Then, before the transmitting coil performs wireless energy transmission with the receiving coil, it is first decoupled by the cross-shaped decoupling coil to build a uniform magnetic field. Since the size parameters of the receiving coil are consistent with the size parameters of the transmitting coil, it means that the receiving coil is much smaller than the size parameters of the decoupled uniform magnetic field multi-coil. Even if the receiving coil is offset from the center point of a transmitting coil, the energy that can be received will not be greatly attenuated. Therefore, the solution of the present application can be applied to a variety of application scenarios and can still maintain a relatively high energy transmission efficiency at a certain deviation distance.

[0029] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0031] Figure 1 is an overall block diagram of a wireless energy transmission device according to an embodiment of the present application;

[0032] Figure 2 is an overall circuit diagram of a wireless energy transmission device according to an embodiment of the present application;

[0033] Figure 3 is a specific circuit diagram of a wireless energy transmission device according to an embodiment of the present application;

[0034] Figure 4 Schematic diagram of a top view of a decoupled uniform magnetic field multi-coil according to an embodiment of the present application;

[0035] Figure 5 Schematic diagram of parameters of a decoupled uniform magnetic field multi-coil according to an embodiment of the present application;

[0036] Figure 6 is a schematic diagram of S11 parameters according to an embodiment of the present application;

[0037] Figure 7 is a magnetic field distribution diagram of the entire transmitting device according to an embodiment of the present application;

[0038] Figure 8 It is a schematic diagram of a base portion 100 and an extension portion 200 according to an embodiment of the present application.

[0039] Reference numerals

[0040] Transmitting circuit 1 , decoupling circuit 2 , receiving circuit 3 , base 100 , extension 200 , transmitting coil 300 , cross-shaped decoupling coil 400 . DETAILED DESCRIPTION

[0041] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be more comprehensive and complete and fully convey the concept of the example embodiments to those skilled in the art.

[0042] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, known methods, devices, realizations or operations are not shown or described in detail to avoid blurring the various aspects of the present application.

[0043] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or micro-control node devices.

[0044] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0045] It should be noted that the "multiple" mentioned in this article refers to two or more. "And / or" describes the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0046] The following is a detailed introduction to the background technology of the embodiments of the present application:

[0047] In the field of energy transmission, due to the shortcomings of the current mature wired transmission in some special areas, such as high maintenance cost, inflexible use, and easy damage, the use of electromagnetic fields for wireless energy transmission technology has become a focus of increasing attention from enterprises and scientific research institutions. In wireless energy transmission technology, there are many media that can be used to transfer energy, and currently more researched are sound waves (mechanical waves), electromagnetic waves, etc. Due to the excellent physical properties of electromagnetic waves themselves, such as extremely wide available frequency band, less influence of the medium than mechanical waves, small attenuation and long transmission distance, the present invention focuses on electromagnetic waves (fields) as the medium for energy transmission. From the perspective of wireless energy transmission technology, in the field of electromagnetic waves, from the form of electromagnetic waves used and the technical means, it can be divided into several forms of wireless energy transmission, such as electromagnetic induction, electric coupling, magnetic coupling, laser coupling, microwave radiation, etc. The technical form used in this application is magnetic coupling resonant wireless energy transmission technology.

[0048] Magnetic coupling resonant wireless energy transmission mainly uses transmitting and receiving coils made of magnetic coils, which receive the electromagnetic field radiated by alternating current through a feed source. Although the electric field also exists, it is not responsible for the realization of wireless energy transmission. The coupled energy is mainly transmitted through the magnetic field between the transmitting coil 300 and the receiving coil.

[0049] Due to the main technical characteristics of using only magnetic field for coupling and near-field radiation of electromagnetic waves, the electromagnetic wave frequency used in this technology is relatively low (usually less than the minimum frequency of 300MHz of microwave radiation, but there are also research applications in the medical field that use 433MHz frequency to power extremely small devices such as robots for medical purposes in the human body), and the coupling effect is mainly achieved in the near-field area (that is, the distance l≤0.1λ, where λ is the wavelength of the resonant electromagnetic wave).

[0050] Several existing schemes for wireless energy transmission using electromagnetic waves all use the near field of the electromagnetic field to achieve the effect of radiating electromagnetic waves, but they all have their own problems. Although electromagnetic induction and electric coupling wireless energy transmission have the advantages of fast frequency conversion speed and high efficiency, the transmission distance between the transmitting coil 300 and the receiving coil is very short. The transmission distance d is relatively small relative to the coil size a. For magnetically coupled resonant wireless energy transmission, the distance d≈a, that is, the transmission distance is approximately equal to the coil size.

[0051] For laser coupling and microwave radiation wireless energy transmission, they use the far field of the electromagnetic field for radiation. Although they both have the advantages of strong directionality and long enough radiation distance. However, the electromagnetic wave frequencies they use are generally high (the microwave radiation frequency is 300MHz-300GHz, and the laser radiation frequency is 3.9×10^14Hz-7.7×10^14Hz). Since high-frequency lines have extremely strict requirements on signals and the construction of the environment, the systems built by these two solutions have extremely high requirements on the accuracy of internal device use and circuit application. The design difficulty of the system is also exponentially higher than that of the systems of several solutions using near-field radiation, and the cost is also rising accordingly. Therefore, the wireless energy transmission system realized by magnetic coupling resonant technology has the advantages of simple system and low device design requirements compared with laser coupling and microwave radiation, and can also increase the distance of energy transmission to a certain extent.

[0052] The general magnetic coupling resonance technology also has corresponding disadvantages. The biggest disadvantage is the extremely high requirement for the alignment between the transmitting coil 300 and the receiving coil. Usually, the maximum efficiency of energy transmission between the transmitting coil 300 and the receiving coil is when the centers of the two coils are completely aligned. Once an offset occurs, the energy transmission efficiency will be drastically attenuated. In practical applications, the overly stringent requirements on users have greatly limited the promotion and use of this technology.

[0053] As for the above shortcomings, the root cause is that the radiated magnetic field generated by a single magnetic coil under the excitation of alternating current is only the largest at its central axis, and will decay exponentially once it deviates. The present application proposes a method for realizing a uniform magnetic field (i.e., the decoupled uniform magnetic field multi-coil in the wireless energy transmission device proposed in the present application), that is, adding a corresponding decoupling coil at the transmitting end of the system so that the "peak" magnetic field emitted by the coil produces an effect of being "flattened". By constructing a uniform magnetic field by this method, the requirements of the magnetic coupling resonance technology for alignment are reduced, and the relatively high energy transmission efficiency can be maintained at a certain deviation distance.

[0054] The implementation details of the technical solution of the embodiment of the present application are described in detail below:

[0055] According to one aspect of the present application, a wireless energy transmission device is provided. Figure 1 is an overall block diagram of a wireless energy transmission device according to an embodiment of the present application. Figure 2 This is the overall circuit diagram of the wireless energy transmission device. Figure 3 This is a specific circuit diagram of the wireless energy transmission device. The detailed introduction is as follows:

[0056] The wireless energy transmission device includes a transmitting device and a receiving circuit; the transmitting device includes a transmitting circuit and a decoupling circuit, the transmitting circuit and the decoupling circuit are arranged in parallel and are both connected to an AC power supply;

[0057] The transmitting circuit includes four transmitting coils 300, and the decoupling circuit includes a cross-shaped decoupling coil 400. The four transmitting coils 300 and the cross-shaped decoupling coil 400 form a decoupled uniform magnetic field multi-coil;

[0058] The receiving circuit includes a receiving coil, and a coupling relationship exists between the receiving coil and each of the transmitting coils 300, and the size parameters of the receiving coil are consistent with the size parameters of the transmitting coil 300;

[0059] The design of the decoupled uniform magnetic field multi-coil can be specifically as follows: the four transmitting coils 300 are arranged in a square matrix; the cross-shaped decoupling coil 400 includes a base 100 and four extensions 200, the base 100 is connected to the four extensions 200, and the base 100 is arranged at the center of the matrix array; the four extensions 200 are respectively arranged between each two adjacent transmitting coils 300;

[0060] The coil winding direction of the four transmitting coils 300 is a first preset direction, and the coil winding direction of the cross-shaped decoupling coil 400 is a second preset direction. The first preset direction is opposite to the second preset direction.

[0061] Specifically, the schematic diagram of the decoupled uniform magnetic field multi-coil can be as follows: Figure 4 As shown, Figure 4 The top view of the decoupled uniform magnetic field multi-coil is shown, in which four transmitting coils 300 and a cross-shaped decoupling coil 400 form the entire decoupled uniform magnetic field multi-coil, so that the transmitting circuit can decouple each transmitting coil 300 through the cross-shaped decoupling coil 400 before wireless energy transmission with the receiving circuit, so that the energy effect of transmission is better. Figure 4 In the embodiment, the cross-shaped decoupling coil 400 is wound in a clockwise direction (i.e., the second preset direction described in the present application), and the four transmitting coils 300 are wound in a counterclockwise direction (i.e., the first preset direction described in the present application). However, it should be noted that in other embodiments, the first preset direction may be set to be clockwise, and the second preset direction may be set to be counterclockwise, as long as the first preset direction can be opposite to the second preset direction.

[0062] like Figure 8 As shown, Figure 8 is a schematic diagram of a base 100 and four extensions 200. It should be noted that the base 100 is Figure 8 The green square area shown, but in fact, the four sides of the green square of the base 100 are not connected. Figure 8 The diagram is only for the purpose of illustrating the base 100 and the extension 200. The actual schematic diagram of the decoupled uniform magnetic field multi-coil is as follows: Figure 4 shown.

[0063] At the 13.56MHz international standard RFID communication protocol frequency band, for a traditional rectangular planar spiral coil, the magnetic field it radiates appears "peaked" from the side, and at a distance with a comparable coil size, even a slight offset of the receiving coil will cause a sharp attenuation of the magnetic field that can be received. The coil matrix implemented in the present application can achieve a "flattened" effect of the originally "peaked" magnetic field at the same distance by adding the cross-shaped decoupling coil 400 when the distance is comparable.

[0064] Since the size parameters of the receiving coil are consistent with the size parameters of the transmitting coil 300, and the coil winding direction of the transmitting coil 300 is consistent with the coil winding direction of the receiving coil, the technical effect brought about by this is that even if the receiving coil is slightly offset, a high wireless energy transmission efficiency can be maintained.

[0065] This application not only designs such a set of coils to achieve such effects, but also proposes such a coil design idea based on the design of the wireless energy transmission device, that is, an uneven DD coil design, that is, the idea that the size parameters of the cross-shaped decoupling coil 400 are inconsistent with the transmitting coil 300. Because the existing decoupling coils are usually designed with the same size parameters as the transmitting coil 300 and the opposite winding direction, taking the four transmitting coils 300 of the square matrix array of this application as an example, if the existing design ideas are followed, then it will undoubtedly increase the material cost of the antenna, and at the same time, it will not be possible to achieve an effect of reducing the volume, which greatly limits its application scenarios.

[0066] The uneven DD coil design concept proposed in the present application can maintain a close distance between the cross-shaped decoupling coil 400 and each transmitting coil 300, thereby reducing material costs and saving space while maintaining a good decoupling effect.

[0067] For a traditional DD coil, its design usually uses two coils with the same structure and opposite winding directions to achieve mutual decoupling, thereby achieving a certain degree of uniformity of the magnetic field. The present application creatively proposes such an uneven design method, aiming to maximize the maintenance of the transmitting function of the transmitting coil 300 without being cut off and to maximize the radiation area, while adding an appropriate decoupling coil that is different from the transmitting coil 300, that is, an uneven decoupling coil, to achieve a decoupling effect for one or more transmitting coils 300.

[0068] This design idea makes the coil design simple and easy to combine, which complies with the working frequency band specified by international standards. In practical applications, it can meet various needs of wireless energy transmission. In addition, the flexible and changeable coil combination also enables this application to meet more complex and changeable environments and various special wireless energy transmission requirements in various practical application scenarios in the future.

[0069] The present application designs a decoupled uniform magnetic field multi-coil, wherein the four transmitting coils 300 are arranged in a square matrix; the cross-shaped decoupling coil 400 includes a base 100 and four extensions 200, the base 100 is connected to the four extensions 200, and the base 100 is arranged at the center of the matrix array; the four extensions 200 are respectively arranged between each adjacent two transmitting coils 300; the coil winding direction of the four transmitting coils 300 is a first preset direction, and the coil winding direction of the cross-shaped decoupling coil 400 is a second preset direction, and the first preset direction is opposite to the second preset direction. Then, before the transmitting coil 300 performs wireless energy transmission with the receiving coil, it is first decoupled by the cross-shaped decoupling coil 400 to build a uniform magnetic field. Since the size parameters of the receiving coil are consistent with the size parameters of the transmitting coil 300, it means that the receiving coil is much smaller than the size parameters of the decoupling uniform magnetic field multi-coil. Even if the receiving coil is offset from the center point of a certain transmitting coil 300, the energy that can be received will not be greatly attenuated. Therefore, the solution of the present application can be applicable to a variety of application scenarios and can still maintain a relatively high energy transmission efficiency at a certain deviation distance.

[0070] In one embodiment of the present application, the transmitting coil 300 is obtained by winding the first preset number of turns in a square shape by the first preset antenna, the distance between each adjacent number of turns is 2 mm, the thickness of the first preset antenna is 2 mm, the side length of the transmitting coil 300 is 82 mm, and the distance between the transmitting circuit and the receiving circuit is 80 mm to 82 mm. The distance between the extension 200 and two adjacent transmitting coils 300 is 4 mm, the length of the extension 200 is 30 mm, and the width of the extension 200 is 86 mm. The cross-shaped decoupling coil 400 is obtained by winding the second preset number of turns in a cross shape by the second preset antenna, the distance between each adjacent number of turns is 2 mm, and the thickness of the second preset antenna is 2 mm.

[0071] Specifically, if Figure 5 As shown, Gap_between in the figure is the distance between the extension part 200 and the transmitting coil 300, Width_out is the thickness of the first preset antenna, Gap_out is the distance between adjacent turns in the transmitting coil 300, Width_in is the thickness of the second preset antenna, Gap_in is the distance between adjacent turns in the cross-shaped decoupling coil 400, a1 is the side length of the transmitting coil 300, because the transmitting coil 300 is wound in a square, b1 is the length of the extension part 200, and the width of the extension part 200 is a1+Gap_between, that is, 82 mm+4 mm=86 mm. The values ​​of the parameters can be shown in the following Table 1:

[0072] Parameter name a1 b1 Width_out Gap_out Width_in Gap_in Gap_between Value(mm) 82 30 2 2 2 2 4

[0073] Table 1

[0074] Furthermore, the transmitting circuit also includes a first inductor, a first capacitor, a second capacitor and a first resistor, and the output end of the AC power supply, the first inductor, the first capacitor, the first resistor, the transmitting coil 300 and the input end of the AC power supply are connected in sequence; the second capacitor is connected in parallel with the transmitting coil 300 and is connected to the first inductor, the first capacitor and the input end of the AC power supply.

[0075] In one embodiment of the present application, based on the above solution, the resonance equation of the transmitting coil 300 is specifically:

[0076]

[0077] In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R Tn For the first resistor, C Tn is the first capacitor, C Tn_2 is the second capacitor, L Tn is the first inductor, L Tn1

[0078] is the self-inductance of the transmitting coil.

[0079] Specifically, if Figure 2 As shown, this application integrates Figure 3 In the four identical transmitting circuits, we get Figure 2 The transmitting circuit shown (i.e., powered by AC power) Tn , the first inductor L Tn , the first resistor R Tn , the first capacitor C Tn , the second capacitor C Tn_2 And the transmitting coil L Tn1 The impedance matching network used in the transmitting circuit is an LCC resonant circuit. R , the coils are tuned using a symmetrical impedance matching network of LCC resonance so that the coils can all operate at 13.56 MHz. Figure 2 As shown, L Tn1 With L R There is coupling M TR , which is mainly responsible for the coupling of wireless energy transmission, so L Tn1 With L R have the same winding direction. Tn1 With L Tre1 Between, due to LTre1 The function of the coil is to release multiple L Tn1 The coupling between the coils, thus L Tn1 With L Tre1 The coupling between re It should be reverse coupling, which is from L Tn1 With L Tre1 The opposite winding directions of the coils can be seen.

[0080] The decoupling circuit further includes a second inductor, a third capacitor, a fourth capacitor and a second resistor. The output end of the AC power supply, the second inductor, the third capacitor, the second resistor, the cross-shaped decoupling coil and the input end of the AC power supply are connected in sequence; the fourth capacitor is connected in parallel with the transmitting coil and is connected to the second inductor, the third capacitor and the input end of the AC power supply. The resonance equation of the cross-shaped decoupling coil is specifically:

[0081]

[0082] In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R Tre For the second resistor, C Tre is the third capacitor, C Tre_2 is the fourth capacitor, L Tre For the second inductor, L Tre1 is the self-inductance of the cross-shaped decoupling coil.

[0083] Similarly, the impedance matching network used in the decoupling circuit is also an LCC resonant circuit, such as Figure 2 As shown, the decoupling circuit consists of an AC power supply AC Tre , cross-shaped decoupling coil L Tre1 , the second resistor R Tre , the third capacitor C Tre , the fourth capacitor C Tre_2 And the second inductor L Tre composition.

[0084] The receiving circuit further includes a third resistor, a fourth resistor, a third inductor, a fifth capacitor and a sixth capacitor; the receiving coil, the third resistor, the fifth capacitor, the third inductor and the fourth resistor are sequentially connected to form a loop, and the sixth capacitor is connected in parallel with the fourth resistor and is connected to the fifth capacitor, the third inductor, the fourth resistor and the receiving coil. The resonance equation of the receiving coil is specifically:

[0085]

[0086] In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R R is the third resistor, RL

[0087] is the fourth resistor, C R is the fifth capacitor, C R_2 is the sixth capacitor, L R

[0088] is the receiving coil self-inductance, L R1 is the third inductor.

[0089] Specifically, if Figure 2 As shown, the receiving circuit consists of a third resistor R R , the fourth resistor R L , the third inductor L R1 , the fifth capacitor C R , the sixth capacitor C R_2 And the receiving coil L R composition.

[0090] Continue as Figure 4 and Figure 5 As shown, the cross-shaped decoupling coil in the middle is L Tre1 Decoupling coil, and the four square planar spiral coils around it are L Tn1 , these four L Tn1 The length and width, line width and turn spacing of the transmitting coil are exactly the same. The coupling circuits of the five coils in the figure are connected to the coils on the front through vias on the back using chip capacitors, inductors and resistors through welding, and the power is also supplied to the front coil through the impedance matching circuit on the back.

[0091] for Figure 4 or Figure 5 The coil shown in the figure is simulated and calculated in the Ansys HFSS high-frequency simulation software. Tn1 The line width and turn spacing are both 2mm, and the internal decoupling coil L Tre When the line width and turn spacing are also 2mm, by adjusting and changing the inductance and capacitance of the back impedance matching network, the five coils can resonate at the predetermined frequency of 13.56MHz. The parameters are represented by S11. The results are as follows Figure 6 As shown (LT1, LT2, LT3, LT4 represent 4 transmitting coils respectively).

[0092] Figure 6 The purple S11 parameter graph is Figure 4 or Figure 5 The cross L in the middle TreThe S11 parameter of the decoupling coil. It can be seen that the S11 parameter of this coil does not show a single trough around 13.56MHz like other coils, but fluctuates around 15MHz, and another very small fluctuation occurs. This can be explained by the fact that there are too many coils that need to be decoupled, resulting in a weak resonance in other similar frequency bands, but it does not affect the performance of the main coil. As for L T1 To L T4 For the four transmitting coils, there is an obvious S11 parameter depression effect of impedance matching at the central frequency band of 13.56MHz, and their S11 parameters all reach a level of about -20dB at 13.56MHz.

[0093] Figure 7 for Figure 4 or Figure 5 After the decoupled uniform magnetic field multi-coil settings are completed, the magnetic field distribution diagram of the entire coil is simulated in Ansys HFSS software.

[0094] from Figure 7 It can be clearly seen that after adding the decoupling coil, the distribution of the magnetic field tends to be more uniform, rather than just a "spike" magnetic field in the very small range of the center of the coil. In this way, after adding the central decoupling coil, not only can the mutual influence between multiple coils be reduced, but the tolerance of the wireless energy transmission system to the degree of misalignment during use can also be effectively improved - even if a certain degree of large deviation occurs, it can be prevented by Figure 7 The construction of the uniform magnetic field shown (i.e. Figure 7 There is a large red magnetic field in the middle, which represents a uniform magnetic field), thereby ensuring that the coupling degree between the transmitting coil and the receiving coil will not drop drastically, ensuring the stable operation of the wireless energy transmission function.

[0095] In summary, compared with the wireless power transmission system based on the traditional planar rectangular spiral coil, the coil designed in the present application can radiate a more uniform magnetic field without sacrificing too much transmission distance, making the wireless energy transmission device more stable.

[0096] Compared with the coil of the traditional symmetrical DD structure, the coil designed in the present application adopts a more flexible asymmetric DD coil design, which makes full use of the plane space, so that more main transmitting coils can be added within a certain range, effectively increasing the radiation area of ​​the main transmitting coil and improving the coverage range of wireless energy transmission.

[0097] The wireless energy transmission device designed in this application is a coil implementation under this design method. In existing practical application scenarios, the operating frequency of the system can be flexibly controlled by adjusting the value of the added compensation capacitor or inductor according to actual needs, without remaking the entire transmitting coil or receiving coil, so it has the advantages of high flexibility, wide application range, easy use and cost saving.

[0098] The present application proposes a coil combination method, which can be used in a group of coils (i.e., 4 L Tn Coil with an L Tre1 Decoupling coil) for L Tn1 The number of coils can be reduced or increased as needed to meet the different needs of different scenarios. Without the need for a new structure design, the coverage of the magnetic field can be further expanded to achieve better anti-deviation effects and more effectively improve the stability of system energy transmission.

[0099] In addition, the above-mentioned figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present application, and are not intended to be limiting. It is easy to understand that the processes shown in the above-mentioned figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0100] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be performed without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A wireless energy transmission device, characterized in that: It comprises a transmitting device and a receiving circuit; the transmitting device comprises a transmitting circuit and a decoupling circuit, the transmitting circuit and the decoupling circuit are arranged in parallel and are both connected to an AC power supply; The transmitting circuit includes four transmitting coils, the decoupling circuit includes a cross-shaped decoupling coil, and the four transmitting coils and the cross-shaped decoupling coil form a decoupled uniform magnetic field multi-coil; The receiving circuit comprises a receiving coil, wherein the receiving coil is coupled to each of the transmitting coils, and the size parameters of the receiving coil are consistent with the size parameters of the transmitting coil; The design of the decoupled uniform magnetic field multi-coil can be specifically as follows: the four transmitting coils are arranged in a square matrix; the cross-shaped decoupling coil includes a base and four extensions, the base is connected to the four extensions, and the base is arranged at the center of the matrix array; the four extensions are respectively arranged between each two adjacent transmitting coils; The coil winding direction of the four transmitting coils is a first preset direction, the coil winding direction of the cross-shaped decoupling coil is a second preset direction, and the first preset direction is opposite to the second preset direction.

2. The wireless energy transmission device according to claim 1, characterized in that: The transmitting coil is obtained by winding a first preset antenna in a square shape with a first preset number of turns, the distance between each adjacent turn is 2 mm, the thickness of the first preset antenna is 2 mm, the side length of the transmitting coil is 82 mm, and the distance between the transmitting circuit and the receiving circuit is 80 mm to 82 mm.

3. The wireless energy transmission device according to claim 2, characterized in that: The distance between the extension part and two adjacent transmitting coils is 4 mm, the length of the extension part is 30 mm, and the width of the extension part is 86 mm.

4. The wireless energy transmission device according to claim 3, characterized in that: The cross-shaped decoupling coil is obtained by cross-winding the second preset antenna with a second preset number of turns, the distance between each adjacent number of turns is 2 mm, and the thickness of the second preset antenna is 2 mm.

5. The wireless energy transmission device according to claim 4, characterized in that: The transmitting circuit also includes a first inductor, a first capacitor, a second capacitor and a first resistor. The output end of the AC power supply, the first inductor, the first capacitor, the first resistor, the transmitting coil and the input end of the AC power supply are connected in sequence; the second capacitor is connected in parallel with the transmitting coil and is connected to the first inductor, the first capacitor and the input end of the AC power supply.

6. The wireless energy transmission device according to claim 5, characterized in that: The resonance equation of the transmitting coil is specifically: In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R Tn For the first resistor, C Tn is the first capacitor, C Tn_2 is the second capacitor, L Tn is the first inductor, L Tn1 is the self-inductance of the transmitting coil.

7. The wireless energy transmission device according to claim 4, characterized in that: The decoupling circuit further includes a second inductor, a third capacitor, a fourth capacitor and a second resistor. The output end of the AC power supply, the second inductor, the third capacitor, the second resistor, the cross decoupling coil and the input end of the AC power supply are connected in sequence; the fourth capacitor is connected in parallel with the transmitting coil and is connected to the second inductor, the third capacitor and the input end of the AC power supply.

8. The wireless energy transmission device according to claim 7, characterized in that: The resonance equation of the cross-shaped decoupling coil is specifically: In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R Tre For the second resistor, C Tre is the third capacitor, C Tre_2 is the fourth capacitor, L Tre For the second inductor, L Tre1 is the self-inductance of the cross-shaped decoupling coil.

9. The wireless energy transmission device according to claim 4, characterized in that: The receiving circuit also includes a third resistor, a fourth resistor, a third inductor, a fifth capacitor and a sixth capacitor; the receiving coil, the third resistor, the fifth capacitor, the third inductor and the fourth resistor are connected in sequence to form a loop, and the sixth capacitor is connected in parallel with the fourth resistor and is connected to the fifth capacitor, the third inductor, the fourth resistor and the receiving coil.

10. The wireless energy transmission device according to claim 9, characterized in that: The resonance equation of the receiving coil is specifically: In the formula, j is an imaginary unit, ω is the angular velocity of the electromagnetic wave, R R is the third resistor, R L is the fourth resistor, C R is the fifth capacitor, C R_2 is the sixth capacitor, L R is the receiving coil self-inductance, L R1 is the third inductor.

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