Compact composite energy transfer communication coil for omnidirectional anti-offset

Abstract

The invention discloses an omnidirectional anti-offset compact composite energy transfer communication coil, and belongs to the technical field of communication coils. The coil adopts an integrated design, and a power coil and a four-orthogonal signal coil are coaxially stacked on a planar magnetic core. Through orthogonal magnetic field layout and frequency planning, interference of higher harmonics generated by power transmission on a communication channel is effectively isolated. The communication coil adopts a unique omnidirectional symmetrical structure, has excellent anti-offset capability, and ensures that a communication link can still be kept stable when a transmitting end and a receiving end are offset in any direction in a plane. The structure is highly integrated, the space is remarkably saved, high-speed and real-time two-way data communication can be established while high-power electric energy is efficiently transmitted, and the power transmission device is particularly suitable for occasions such as implantable medical equipment and underwater devices which have strict requirements for the size and reliability.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of communication coils, and particularly relates to a compact composite energy transmission communication coil with omnidirectional anti-offset. BACKGROUND

[0002] With the rapid development of wireless charging technology, its application has been extended from consumer electronics to industrial and special scenarios with high requirements for synchronous transmission of energy and information. For example, implantable medical devices need to transmit real-time image data to the outside of the body during in-vivo examination; smart home devices need to feed back battery status during charging to realize precise management; underwater devices need to transmit collected data and images to the sea surface platform while charging. These scenarios generally face common challenges such as space limitation, complex environment, and high real-time requirement.

[0003] Traditional schemes usually use independent coils for energy transmission and communication, which has the following outstanding problems: 1. Energy coil and communication coil are arranged separately, occupying a large space, which is difficult to meet the needs of device miniaturization and integration; 2. High-order harmonics generated during energy transmission will seriously interfere with communication signals, especially when the position is offset, the interference is intensified, resulting in unstable or even interrupted communication link; 3. The reliability of conventional wireless communication (such as Wi-Fi, 5G) is reduced in multi-path attenuation environments such as underwater and in-vivo; 4. The data processing mode of storing first and then transmitting cannot meet the real-time interaction requirement, affecting the system response speed and control accuracy.

[0004] Therefore, how to realize the synchronization and stable performance of high-power wireless charging and high-speed real-time communication in a limited space, and have good anti-offset and anti-interference ability, has become a key bottleneck restricting the landing of this technology in high-demand scenarios. The existing technology still lacks a compact, energy and communication integrated, omnidirectional anti-offset comprehensive solution. SUMMARY

[0005] To solve the above technical problems, the application provides a compact composite energy transmission communication coil with omnidirectional anti-offset, which adopts integrated design and coaxially stacks power coil and four orthogonal communication coils on a planar magnetic core. Through orthogonal magnetic field layout and frequency planning, the interference of high-order harmonics generated by power transmission on the communication channel is effectively isolated. The communication coil adopts a unique omnidirectional symmetric structure, which has excellent anti-offset ability, ensuring that the communication link remains stable when the transmitting and receiving ends are offset in any direction in the plane.

[0006] To achieve the above purpose, the application adopts the following technical scheme:

[0007] A compact composite energy transmission communication coil with omnidirectional anti-offset, comprising a communication coil, an insulating material, a power coil, and a magnetic core which are sequentially stacked from top to bottom, wherein,

[0008] The communication coil is coaxially arranged with the power coil;

[0009] The communication coil is a four-phase communication coil, which is composed of four sub-coils in a series connection to form an omnidirectional symmetric structure, which ensures that the communication link remains stable when the transmission end and the receiving end are offset in any direction in the plane.

[0010] Further, the four sub-coils are orthogonally symmetrically arranged at azimuth angles of 0°, 90°, 180° and 270°, and the specific series connection mode is that the outgoing end of the first sub-coil is connected to the incoming end of the second sub-coil, the outgoing end of the second sub-coil is connected to the incoming end of the third sub-coil, and the outgoing end of the third sub-coil is connected to the incoming end of the fourth sub-coil, thereby forming a complete series loop.

[0011] Further, the magnetic field directions generated by adjacent sub-coils in the four sub-coils are opposite.

[0012] Further, by designing the communication coil as an orthogonal magnetic field layout and combining independent communication frequency planning, the interference of high-order harmonics generated by the power coil during operation on the communication channel is effectively isolated.

[0013] Further, the power coil is a multi-turn circular coil wound with Litz wire; the communication coil is a single-turn structure, and the wire thereof is also Litz wire and is embedded in a preset groove of the substrate.

[0014] Further, the magnetic core is a planar manganese-zinc ferrite core arranged at the back of the power coil to enhance the magnetic field.

[0015] Further, the four sub-coils have the same structure and size, and when the communication coil is not offset relative to the power coil, the center of the communication coil is aligned with the center of the power coil.

[0016] Further, the omnidirectional anti-offset characteristic of the communication coil is that when the communication coil is offset in any direction in the plane relative to the power coil, the electromotive forces induced in each sub-coil by the alternating magnetic field of the power coil cancel each other out, so that the total induced electromotive force of the communication coil is zero, thereby realizing decoupling from the power magnetic field.

[0017] Further, it further includes a substrate and packaging material for fixing and packaging the communication coil, insulating material, power coil and magnetic core, forming an integrated compact structure.

[0018] Further, the communication coil and the power coil are respectively connected to independent communication ports and power ports to support the simultaneous performance of energy transmission and data communication.

[0019] The beneficial effects of the present application are that:

[0020] High integration, compact structure: through the integration of composite architecture design, the power coil and the communication coil are coaxially stacked and integrated in a single magnetic core substrate, replacing the traditional split layout, significantly reducing the overall volume and occupied space of the coil module, meeting the strict requirements of space-limited devices such as implantable and underwater devices.

[0021] Real-time and reliable synchronization: while achieving kilowatt-level efficient wireless energy transmission, an independent and high-speed real-time communication link based on near-field coupling is established. Avoiding the lag of data storage post-processing, it supports the instant interaction of energy state, control instructions and image data, improving the overall intelligent level and response speed of the system.

[0022] Strong anti-interference, omnidirectional anti-offset: innovative four-orthogonal communication coil layout and magnetic field orthogonal design, combined with targeted frequency planning, effectively isolates the electromagnetic interference of power transmission high-order harmonics on the communication frequency band. The unique omnidirectional symmetric structure ensures that the communication signal remains stable when the transmitting end and receiving end are offset in any plane direction (X / Y axis), greatly improving the position fault tolerance and robustness of the system.

[0023] Superior performance, wide applicability: this design takes into account high power transmission efficiency and high communication quality (low bit error rate), solving the problem of energy and communication transmission in complex electromagnetic environments. Its modular design is easy to integrate with existing systems and can be widely used in medical devices, underwater exploration, industrial robots, smart homes and other fields. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Figure 1 is a schematic diagram of a compact composite energy transmission and communication coil structure with omnidirectional anti-offset;

[0025] Figure 2 Figure 2 is a schematic diagram of the communication coil structure;

[0026] Figure 3 Figure 3 is a schematic diagram of the magnetic lines of force between the power coil and the communication coil;

[0027] Figure 4 (a) is a schematic diagram of the power coil support substrate;

[0028] Figure 4 (b) is a schematic diagram of the communication coil isolation substrate;

[0029] Figure 5 Figure 5 is a schematic diagram of the power coil wire;

[0030] Figure 6 Figure 6 is a schematic diagram of the communication coil wire;

[0031] Figure 7 Figure 7 is a schematic diagram of the manganese-zinc ferrite core;

[0032] Figure 8 Exploded view of a composite energy transmission and communication coil;

[0033] Figure 9 This is an installation diagram of a composite energy transmission and communication coil.

[0034] Figure label:

[0035] Magnetic core 1, power coil 2, insulating material 3, communication coil 4;

[0036] First sub-coil 41, second sub-coil 42, third sub-coil 43, fourth sub-coil 44;

[0037] First sideline 11, second sideline 12, third sideline 13, fourth sideline 14, fifth sideline 15, sixth sideline 16, seventh sideline 17, eighth sideline 18. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0039] like Figure 1 As shown, the omnidirectional anti-offset compact composite power transmission and communication coil of the present invention includes a planar magnetic core 1, a power coil 2, an insulating material 3, and a communication coil 4 stacked sequentially. The planar magnetic core 1 can enhance the magnetic field of the coil, and due to its special shape, it can be arbitrarily combined and laid out according to the form of the power coil 2. The power coil 2 serves as the carrier of power transmission in the wireless charging system, and its shape is not limited, and it can be circular, square, or rectangular. The insulating material 3 isolates the electrical contact between the power coil 2 and the communication coil 4 to prevent short circuits and arcing. The communication coil 4 serves as the carrier of wireless information transmission.

[0040] In wireless charging systems, these composite power transfer and communication coils are used in pairs: one set at the charging end and one set at the receiving end. Each set has a unique structure. Figure 1 The structure shown has the following configuration: at the charging end, power coil 2 and communication coil 4 are concentrically distributed in the xy-plane, 1mm apart on the z-axis, with no offset between them. At the receiving end, power coil 2 and communication coil 4 are concentrically distributed in the xy-plane, 1mm apart on the z-axis, with no offset between them. However, during wireless charging, the corresponding composite power transmission and communication coils at the charging and receiving ends may experience relative offset. The following analysis will focus on the offset between the power coil 2 at the charging end and the communication coil 4 at the receiving end.

[0041] According to Faraday's law of electromagnetic induction, when power coil 2 and communication coil 4 are used in combination, the higher harmonic components in power coil 2 will interfere with the electrical signal in communication coil 4. To reduce the interference of power coil 2 on communication coil 4, a four-orthogonal communication coil 4 with omnidirectional symmetry and orthogonal arrangement is designed, as shown in the schematic diagram below.Figure 2 As shown.

[0042] In order to show intuitive, clear, Figure 2 The first edge line 11 and the second edge line 12, the third edge line 13 and the fourth edge line 14, the fifth edge line 15 and the sixth edge line 16, the seventh edge line 17 and the eighth edge line 18 of the communication coil 4 shown in the middle have a certain distance, and in actual application, the first edge line 11 and the second edge line 12, the third edge line 13 and the fourth edge line 14, the fifth edge line 15 and the sixth edge line 16, the seventh edge line 17 and the eighth edge line 18 line overlap effect is best. The incoming line of the communication coil 4 is the first edge line 11 of the first coil 41, and the outgoing line of the communication coil 4 is the seventh edge line 17 of the fourth sub-coil 44. For the sake of clarity, the four sub-coils of the communication coil 4 are regarded as independent coils, and each independent sub-coil is connected in series, that is, the outgoing line eighth edge line 18 of the first sub-coil 41 is connected to the incoming line second edge line 12 of the second sub-coil 42, the outgoing line third edge line 13 of the second sub-coil 42 is connected to the incoming line fifth edge line 15 of the third sub-coil 43, and the outgoing line fourth edge line 14 of the third sub-coil 43 is connected to the incoming line sixth edge line 16 of the fourth sub-coil 44. When the alternating current flows into the communication coil 4 from the incoming line port and flows out from the outgoing line port, a magnetic field will be generated on the communication coil 4. According to Ampere's law, the magnetic field generated by the first sub-coil 41 and the second sub-coil 42 is opposite in direction, the magnetic field generated by the second sub-coil 42 and the fourth sub-coil 44 is opposite in direction, the magnetic field generated by the third sub-coil 43 and the fourth sub-coil 44 is opposite in direction, and the magnetic field generated by the first sub-coil 41 and the third sub-coil 43 is opposite in direction.

[0043] According to Faraday's law of electromagnetic induction, when the magnetic flux through the communication coil 4 changes, the induced electromotive force at both ends of the first sub-coil 41 and the induced electromotive force at both ends of the second sub-coil 42 are opposite in polarity, the induced electromotive force at both ends of the second sub-coil 42 and the induced electromotive force at both ends of the fourth sub-coil 44 are opposite in polarity, the induced electromotive force at both ends of the fourth sub-coil 44 and the induced electromotive force at both ends of the third sub-coil 43 are opposite in polarity, and the induced electromotive force at both ends of the third sub-coil 43 and the induced electromotive force at both ends of the first sub-coil 41 are opposite in polarity.

[0044] As Figure 3 shown, loop C a is the power coil 2 loop, C b1 is the first loop of the communication coil 4, that is, the first sub-coil 41, C b2 is the second loop of the communication coil 4, that is, the first sub-coil 42, C b3 is the third loop of the communication coil 4, that is, the first sub-coil 43, C b4The fourth loop of the communication coil 4 is the first sub-coil 44. A coordinate system is established with the loop of the power coil 2 as the XY plane, the direction perpendicular to the power coil 2 as the Z axis, and the center point of the power coil 2 as the origin of the XYZ coordinate system.

[0045] Assuming that the current passing through the loop C a is I a , according to the Biot-Savart law, it is known that:

[0046] (1)

[0047] Let the intermediate variable:

[0048] (2)

[0049] Then:

[0050] (3)

[0051] where V is the current distribution area, is the source point position vector, r is the field point position vector, is the vacuum permeability, is the Hamiltonian operator. B is the magnetic flux density, also known as the magnetic induction intensity, and the vector A is called the magnetic potential, and J represents the current density vector.

[0052] From the above formula, it is known that the magnetic flux density B is equal to the curl of the magnetic potential A.

[0053] Assuming that the current passing through the loop C a is I a , according to the Lenz law, the induced electromotive force E is:

[0054] (4)

[0055] According to formula (3), the expression of the magnetic flux is obtained:

[0056] (5)

[0057] That is, the magnetic flux generated by the current-carrying loop C1 on the surface enclosed by the closed loop C2 is:

[0058] (6)

[0059] where C1 is the first current-carrying loop, the current in C1 is I1, r1 is the point position vector on the first current-carrying loop C1, C2 is the second current-carrying loop, and r2 is the point position vector on the second current-carrying loop C2.

[0060] Based on the above theory, assuming that the current on the loop of the power coil 2 is I aThen the power coil 2 current in the communication coil 4 first loop C b1 The magnetic flux generated above is:

[0061] (7)

[0062] In the formula, each letter content is similar to the previous text, and the subscript corresponds to the corresponding coil, and will not be repeated.

[0063] Let the height of the communication coil 4 from the power coil 2 be h, C b1 , C b2 , C b3 , C b4 The side length of each is b, and the closed curve C b1 The direction of the closed curve C b1 The line integral of the magnetic vector potential A along the closed curve C b1 The magnetic flux through the open surface S b1 The size of the magnetic flux is related to the closed curve C b1 And the shape and size of the open surface S b1 .

[0064] Let the radius of the loop C a The mathematical expression of the curve C a is:

[0065] (8)

[0066] C b1 The side length is b, and the center is (t0, t1), t0, t1 are constants, then the mathematical expression of the curve C b1 is:

[0067] (9)

[0068] In the arc segment, let Simplify to get the mathematical expression of the curve C b1 :

[0069] (10)

[0070] Let Substitute formula (9) to get:

[0071] (11)

[0072] Similarly, the magnetic flux of the other loops of the communication coil 4 can be obtained:

[0073] (12)

[0074] (13)

[0075] (14)

[0076] In combination with the four-coil structure, it can be known that:

[0077] (15)

[0078] (16)

[0079] E ab is the total induced electromotive force in the communication coil 4, E ab1 is the induced electromotive force in the first sub-coil 41, E ab2 is the induced electromotive force in the second sub-coil 42, E ab3 is the induced electromotive force in the third sub-coil 43, E ab4 is the induced electromotive force in the fourth sub-coil 44.

[0080] Substituting formulas (11)-(14) into formula (16), when the communication coil has a deviation in the x-axis, i.e. ;

[0081] (17)

[0082] It can be known through substitution method and partial integration method that, i.e. the communication coil 4 and the power coil 2 are decoupled in the x-axis. Similarly, when the communication coil 4 has a deviation in the y-axis, i.e. , i.e. the communication coil 4 and the power coil 2 are decoupled in the y-axis. That is, the composite power transmission and communication coil has the characteristic of omnidirectional anti-deviation.

[0083] Embodiment

[0084] The preparation and implementation process of the power transmission and communication coil are described as follows.

[0085] As shown in FIGS. 4(a)-4(b), first, material preparation and pretreatment are performed: a circular double-layer substrate is prepared from FR4 material, the lower layer is a support substrate with a thickness of 1.0 mm, and the upper layer is an isolation substrate with a thickness of 1.5 mm; a groove with a depth of 8 mm is carved on the lower layer substrate by using laser precision engraving technology for embedding the power coil, and a groove with a depth of 0.5 mm is carved on the upper layer substrate for embedding the communication coil.

[0086] As Figure 5As shown, the power coil conductor is made of Litz wire, which is made of more than 1,000 strands of 0.1mm diameter enameled copper wire, which effectively suppresses the skin effect and proximity effect under high frequency operation and reduces AC resistance; the equivalent cross-sectional area is not less than 2.5mm² based on the target power (10kW) and operating frequency (100kHz).

[0087] like Figure 6 As shown, the communication coil conductor is made of Litz wire, which consists of 100 strands of 0.1mm diameter enameled copper wire. The diameter of each strand is 0.1mm to meet the requirements of low ohmic loss and high Q value in high-frequency communication of 3-15MHz.

[0088] like Figure 7 As shown, the power coil and the communication coil share a magnetic core. The magnetic core material is manganese-zinc power ferrite with an initial permeability μi≥2300 and a saturation magnetic flux density Bs≥450mT (25℃). It is processed into a square sheet with a side length of 50mm and a thickness of 3mm and placed on the back of the power coil. The arrangement is made to make it coincide with the power coil as much as possible.

[0089] Subsequently, coil manufacturing and assembly are carried out: the communication coil wires are precisely embedded into the pre-set grooves of the upper isolation substrate, and wound into four single-turn fan-shaped coils with a radius of 50mm (each semi-circular coil has a radius of 50mm, which is approximately 0.33 times the radius of 150mm, with 1 turn), and arranged orthogonally symmetrically at azimuth angles of 0°, 90°, 180°, and 270°, fixed with high-temperature resistant epoxy resin, and a terminal is led out at the center of the coil; the power coil Litz wire is wound into the grooves of the lower support substrate to form a circular coil with an outer diameter of 150mm and a total of 10 turns, with a turn spacing of 9mm to maintain a gap to prevent short circuits, and is also fixed with epoxy resin and soldered with high-current connectors. Next, lamination integration is performed: such as... Figure 8-9 As shown, the upper substrate with the communication coil assembled and the lower substrate with the power coil assembled are concentrically aligned. After applying thermally conductive silicone in the middle, pressure and temperature are applied to laminate and solidify the components to form an integrated coil assembly. Finally, manganese zinc ferrite magnetic chips are arranged and installed on the back of the power coil.

[0090] After physical assembly, circuit connections and system integration are performed: the two leads of the power coil are connected to the power terminals (P+, P-), and then connected to a high-frequency inverter power supply or rectifier filter circuit; the input and output terminals of the communication coil are connected to the communication port, and then connected to a communication modulation and demodulation circuit based on DSP or MCU. This system can realize full-bridge / half-bridge inverter drive, power regulation, and real-time data transmission and reception based on ASK or BPSK modulation during the charging process.

[0091] Finally, the finished product is tested, calibrated and packaged: using LCR table to measure the inductance and quality factor of the power coil, and test the transmission efficiency and temperature rise under rated power; measure the self-inductance and mutual inductance of each communication coil, verify the orthogonal decoupling effect. In the shielding room, the system is debugged, the synchronous working ability of 10kW level wireless charging and high-speed communication is verified, and the communication bit error rate is less than 10 -6 After the test, the coil assembly is filled with heat-conducting epoxy resin to provide mechanical protection and enhance heat dissipation, and water-tight connectors are selected for power and communication interfaces to ensure their reliability and durability in complex environments.

[0092] The above specific embodiments further illustrate the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A compact, omnidirectional, offset-resistant composite power transmission and communication coil, characterized in that, It includes, from top to bottom, a communication coil, insulating material, a power coil, and a magnetic core, stacked sequentially. The communication coil and the power coil are arranged coaxially; The communication coil is a four-orthogonal communication coil, which consists of four sub-coils connected in series to form an omnidirectional symmetrical structure. The omnidirectional symmetrical structure is used to ensure that the communication link remains stable when the transmitter and receiver are offset in any direction in the plane.

2. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 1, characterized in that, The four sub-coils are arranged orthogonally and symmetrically with azimuth angles of 0°, 90°, 180°, and 270°. The specific way they are connected in series is as follows: the output end of the first sub-coil is connected to the input end of the second sub-coil, the output end of the second sub-coil is connected to the input end of the third sub-coil, and the output end of the third sub-coil is connected to the input end of the fourth sub-coil, thus forming a complete series circuit.

3. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 2, characterized in that, Among the four sub-coils, the magnetic fields generated by adjacent sub-coils are in opposite directions.

4. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 1, characterized in that, By designing the communication coil with an orthogonal magnetic field layout and combining it with independent communication frequency planning, the interference of high-order harmonics generated by the power coil during operation on the communication channel is effectively isolated.

5. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 1, characterized in that, The power coil is a multi-turn circular coil wound with Litz wire; the communication coil is a single-turn structure, and its conductor is also Litz wire, which is embedded in a pre-set groove in the substrate.

6. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 1, characterized in that, The magnetic core is a planar manganese-zinc ferrite core, which is placed on the back of the power coil to enhance the magnetic field.

7. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 1, characterized in that, The four sub-coils have the same structure and size, and when there is no relative offset between the communication coil and the power coil, the center of the communication coil is aligned with the center of the power coil.

8. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 1, characterized in that, The omnidirectional anti-offset characteristic of the communication coil is that when the communication coil is offset relative to the power coil in any direction in the plane, the electromotive force induced in each sub-coil by the alternating magnetic field of the power coil cancels each other out, so that the total induced electromotive force of the communication coil is zero, thereby achieving decoupling from the power magnetic field.

9. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 1, characterized in that, It also includes a substrate and encapsulation material for fixing and encapsulating the communication coil, insulating material, power coil and magnetic core, forming an integrated compact structure.

10. The omnidirectional anti-offset compact composite power transmission and communication coil according to claim 1, characterized in that, The communication coil and the power coil are respectively connected to independent communication ports and power ports to support the synchronous transmission of energy and data communication.

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