Magnetic coupling mechanism for wireless power transfer system and its anti-offset design method

Abstract

The present invention discloses a magnetic coupling mechanism for a wireless power transmission system and an anti-deviation design method thereof, wherein the magnetic coupling mechanism includes a transmitting end and a receiving end magnetic coupling mechanism, the transmitting end is a double-layer planar structure, the lower layer is a circular ring coil, the upper layer is a plurality of identically designed fan-ring coil units spliced ​​and arranged to form a fan-ring coil array with the same outer diameter as the lower ring, all fan-ring coil units are connected in series, and the receiving end is a single circular ring coil. The anti-deviation design method of the magnetic coupling mechanism establishes a mutual inductance calculation model of the magnetic coupling mechanism of the transmitting end multi-coil combination, optimizes multiple key parameters of the fan-ring coil unit, and constructs a transmitting end magnetic coupling mechanism with stable magnetic field distribution characteristics, thereby improving the anti-deviation capability of the magnetic coupling resonant wireless power transmission system. The anti-deviation design method increases the effective area of ​​the wireless power transmission area while ensuring the power stability during the system's wireless power transmission process, so that the system has better anti-deviation capability.

Description

Technical Field

[0001] This invention relates to a magnetic coupling mechanism for wireless power transmission systems and its anti-offset design method, belonging to the field of magnetic coupling wireless power transmission technology. Background Art

[0002] Wireless power transfer (WPT) is a technology that uses electromagnetic fields to transmit electrical energy over long distances. This technology has wide applications in charging devices, drones, electric vehicles, and robotics. The rapid development of WPT has not only driven innovation in new electronic devices but also made possible the widespread adoption of smart cities, automated systems, and electric transportation in the future.

[0003] In wireless power transfer systems, the design of the magnetic coupling mechanism plays a crucial role in transmission efficiency and stability. As a key component, the magnetic coupling mechanism directly affects the efficiency of the entire wireless power transfer process. However, due to factors such as receiver position offset, physical obstacles, and load variations in real-world applications, wireless power transfer systems may face problems such as reduced efficiency and unstable energy transmission. To ensure efficient system operation, designing anti-offset mechanisms to mitigate the negative impact of relative positional changes between devices has become an important topic in wireless power transfer technology. Therefore, optimizing the design and anti-offset capabilities of the magnetic coupling mechanism not only helps improve the system's transmission efficiency but also enhances its adaptability and reliability in complex environments. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a magnetic coupling mechanism for wireless power transmission systems and a method for its anti-offset design. The magnetic coupling mechanism with anti-offset design can enhance the tolerance of receiver position offset and expand the application scenarios of wireless power transmission systems.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A magnetic coupling mechanism for a wireless power transmission system, comprising: a transmitting magnetic coupling mechanism and a receiving magnetic coupling mechanism for realizing wireless power transmission; the transmitting magnetic coupling mechanism comprising upper and lower coils, the lower coil being a circular ring coil and the upper coil being a fan-ring coil array, the upper coil being disposed on the upper surface of the lower coil, the fan-ring coil array comprising multiple fan-ring coil units disposed on the same plane, the multiple fan-ring coil units being uniformly arranged circumferentially around the same common central axis, the outer diameter of the fan-ring coil array being equal to the outer diameter of the lower circular ring coil, all fan-ring coil units being connected in series, and the fan-ring coil array being connected in series with the lower circular ring coil;

[0007] The receiving end magnetic coupling mechanism includes a receiving end circular coil, which is arranged parallel to and directly opposite the fan-ring coil array.

[0008] As a preferred embodiment of the magnetic coupling mechanism, the fan-ring coil unit employs a planar helical structure for coil winding.

[0009] As a preferred embodiment of the magnetic coupling mechanism, in the sector ring coil array, the included angles between the axes of symmetry of adjacent sector ring coil units are equal. When the number of sector ring coil units is... At that time, the included angle between the axes of symmetry of adjacent sector coil units is , It is a positive integer.

[0010] A wireless power transmission system includes a magnetic coupling mechanism, a transmitter, and a receiver. The transmitter includes a transmitter DC power supply, a transmitter full-bridge inverter, and a transmitter resonant network connected in sequence, with the transmitter resonant network connected to the transmitter magnetic coupling mechanism. The receiver includes a receiver resonant network, a receiver full-bridge rectifier module, and a receiver battery load connected in sequence, with the receiver resonant network connected to the receiver magnetic coupling mechanism.

[0011] Based on the aforementioned anti-offset design method for magnetic coupling mechanisms in wireless power transmission systems, the anti-offset design method includes the following steps:

[0012] Step 1: Given the outermost turn radius of the lower-level circular coil at the transmitter. and number of turns The outermost turn radius of the receiving end circular coil and number of turns And the vertical height between the transmitting end magnetic coupling mechanism and the receiving end magnetic coupling mechanism. ;

[0013] Step 2, preset mutual inductance volatility limit axial offset distance Step size of change and the radius of the receiving end circular coil and the spatial rectangular coordinate system Axis angle Step size of change The spatial rectangular coordinate system has its origin at the center of the lower-layer annular coil of the transmitter. The plane is the plane where the lower ring coil of the transmitter is located. The axis is oriented in the direction of the receiving end's circular coil; initially, the axial offset distance... The value is 0, and the radius of the receiving end circular coil is relative to the spatial rectangular coordinate system. Axis angle =0;

[0014] Step 3: Determine the value range of the parameters to be optimized in the anti-offset design, and number each parameter starting from 1. The parameters to be optimized include the small arc radius of the fan-ring coil unit. Number of turns per fan-ring coil unit and the corresponding central angle of the fan-ring coil unit ,in, , and All represent serial numbers. , , , , and These are the small arc radius of the fan-ring coil unit, the number of turns of the fan-ring coil unit, and the number of all numbers corresponding to the central angle of the fan-ring coil unit;

[0015] Step 4: Iterate through all combinations of parameters to be optimized. In each combination, starting from 0, proceed according to the step size. Change the axial offset distance between the receiver's ring coil and the transmitter's lower ring coil. And at the same axial offset distance, starting from 0 according to the step size Changing the radius of the receiving end's circular coil relative to the spatial rectangular coordinate system Axis angle , The maximum value is , The maximum value is ;

[0016] Step 5, at the current axial offset distance corresponding to the current combination. Down, included angle Each time a change is made, the mutual inductance between the corresponding transmitting and receiving magnetic coupling mechanisms is calculated. Find the maximum and minimum values ​​of all mutual inductances at the current axial offset distance, and calculate the mutual inductance fluctuation. ;

[0017] Step 6: Determine whether the mutual inductance fluctuation corresponding to the current axial offset distance is greater than the mutual inductance fluctuation rate limit. If so, then the previous axial offset distance is taken as the maximum axial offset distance of the current combination; otherwise, the current axial offset distance is increased by one step. , as the new current axial offset distance and return to step 5;

[0018] Step 7: Based on Steps 4-6, find the maximum axial offset distance for each combination. Find the maximum value among all the maximum axial offset distances. If there is only one maximum value, take the combination corresponding to the maximum value as the optimal parameter combination; otherwise, proceed to Step 8.

[0019] Step 8: If there are at least two maximum values, calculate the amount of wire required for the winding of the transmitter magnetic coupling mechanism under the combination corresponding to each maximum value, and select the combination with the minimum amount of wire required as the optimal parameter combination.

[0020] As a preferred embodiment of the anti-offset design method, the calculation formula for the mutual inductance fluctuation is as follows:

[0021] ,

[0022] in, The included angles are the current axial offset distances. From 0 to The maximum and minimum values ​​among all mutual inductances;

[0023] Mutual inductance between the transmitting and receiving magnetic coupling mechanisms The calculation formula is as follows:

[0024] ,

[0025] in, This refers to the number of fan-ring coil units. Let be the mutual inductance of the k-th sector loop coil unit to the magnetic coupling mechanism at the receiving end. This represents the mutual inductance between the lower-level annular coil at the transmitting end and the magnetic coupling mechanism at the receiving end. The number of turns of the fan-ring coil unit. For the k-th sector coil unit The first turn of the receiving end circular coil Mutual inductance of turns, The lower ring coil of the transmitting end The first turn of the receiving end circular coil Mutual inductance of turns.

[0026] As a preferred embodiment of the anti-offset design method, the calculation formula for the amount of wire used in the coil winding of the transmitter magnetic coupling mechanism is as follows:

[0027] ,

[0028] in, This refers to the amount of wire used for winding the coil of the magnetic coupling mechanism at the transmitting end. This refers to the number of fan-ring coil units. The number of turns of the fan-ring coil unit. For the central angle corresponding to the fan-ring coil unit, and These are the two straight sides of the fan-shaped coil unit and the coordinate system, respectively. The included angle of the axis, , These are the fan-ring coil units. Larger and smaller arc radii , Let be the length of the straight side of the sector loop coil unit. , The lower ring coil of the transmitting end The radius of the circle corresponding to the turn. This refers to the turn-to-turn distance of the lower-layer annular coil at the transmitting end.

[0029] A computer device includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor executes the computer program to implement the steps of the anti-offset design method.

[0030] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the offset-resistant design method.

[0031] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects:

[0032] 1. This invention proposes a wireless power transmission system with a multi-coil combination at the transmitting end. The transmitting end magnetic coupling mechanism comprises a double-layer structure: a lower circular coil and an upper sector-ring coil array. The lower circular coil provides the main power source for the center of the power supply area where the coil is located. The upper sector-ring coil has mutual inductance compensation characteristics, which can effectively increase the effective mutual inductance area of ​​the power supply area, resulting in a more uniform magnetic field distribution. The transmitting end magnetic coupling mechanism, composed of the upper sector-ring coil array and the lower circular coil, can effectively improve the positional offset tolerance of the receiving end during wireless power transmission. There is partial overlap between the sector-ring coil units in the sector-ring coil array. This design reduces the mutual inductance between two adjacent sector-ring coil units, which plays a significant role in reducing overall system losses and optimizing the magnetic field distribution between power supply areas.

[0033] 2. This invention proposes an anti-offset design method, including mutual inductance calculation of the magnetic coupling mechanism of the multi-coil combination at the transmitter and optimization of the size of the sector coil unit at the transmitter. The mutual inductance calculation of the magnetic coupling mechanism of the multi-coil combination at the transmitter is performed by decomposing the sector coil into radial infinitesimal elements, calculating the local mutual inductance separately, and then summing and combining them to calculate the overall mutual inductance of the transmitter's magnetic coupling mechanism to the receiver's magnetic coupling mechanism. The optimization of the coil unit size at the transmitter is based on the constraint of the basic geometric dimensions. The parameters and value range of the sector coil to be optimized are specified, and the mutual inductance values ​​under different axial offset distances are calculated through parametric scanning. Parameter combinations that satisfy the mutual inductance fluctuation rate constraint are selected, and the scheme with the minimum amount of wire is chosen as the final design.

[0034] 3. The anti-offset design method proposed in this invention increases the effective area of ​​the wireless power transmission region while ensuring power stability during the wireless power transmission process, thereby giving the system better anti-offset capability. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the magnetic coupling mechanism based on a combination of multi-sector loop coils and circular coils provided by the present invention;

[0036] Figure 2 This is a top view of the magnetic coupling mechanism based on a combination of multi-sector loop coils and circular coils provided by the present invention;

[0037] Figure 3 This is a schematic diagram of the actual winding of the planar spiral structure of the fan-ring coil unit provided by the present invention;

[0038] Figure 4 This is a distribution characteristic diagram of the normalized mutual inductance of a single circular coil and a circular receiving coil as a function of the receiving end position offset, provided in an embodiment of the present invention.

[0039] Figure 5 This is an approximate calculation schematic diagram of the closed fan-ring combination structure of the fan-ring coil unit provided by the present invention;

[0040] Figure 6 This is a schematic diagram illustrating the mutual inductance calculation between the transmitting end fan-ring coil unit and the receiving end planar spiral coil provided by the present invention;

[0041] Figure 7 This is a flowchart of the multi-parameter optimization process for the anti-offset design transmitter provided by the present invention;

[0042] Figure 8 This is a diagram showing the distribution characteristics of the normalized mutual inductance of the magnetic coupling mechanism based on the combination of multi-sector loop coils and circular coils and the circular receiving coil as a function of the receiving end position offset, provided in an embodiment of the present invention.

[0043] Figure 9This is a simulation characteristic diagram of the normalized mutual inductance of a magnetic coupling mechanism based on a combination of multi-sector loop coils and circular coils and a single circular transmitting coil as a function of receiver position offset, provided in an embodiment of the present invention.

[0044] Figure 10 This is a graph showing the characteristic of the inductance measurement value of a single circular transmitting coil as a function of the position offset of the receiving end, provided in an embodiment of the present invention.

[0045] Figure 11 This is a graph showing the characteristic of the inductance measurement value of a transmitter based on a combination of multi-sector loop coils and circular coils as a function of the receiver position offset, provided by an embodiment of the present invention.

[0046] Figure 12 This is a graph showing the characteristics of mutual inductance measurements between a magnetic coupling mechanism based on a combination of multi-sector loop coils and circular coils and a single circular transmitting coil and the same circular receiving coil, provided in an embodiment of the present invention, as a function of position offset. Detailed Implementation

[0047] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0048] This invention proposes a magnetic coupling mechanism for a wireless power transmission system, comprising a transmitting magnetic coupling mechanism and a receiving magnetic coupling mechanism. The transmitting magnetic coupling mechanism includes a multi-coil combination at the transmitting end, and the receiving magnetic coupling mechanism includes a circular ring coil at the receiving end.

[0049] like Figure 1 , Figure 2 As shown, the transmitter multi-coil combination consists of two layers of coils: a lower ring coil and an upper sector ring coil array. Several identical sector ring coil units are arranged on a plane at specified intervals. The outer diameter of the sector ring coil array is the same as that of the lower ring coil. All coils of the transmitter are connected in series.

[0050] The receiving coil adopts a circular ring coil structure. The circular ring coil is a commonly used coil structure in the receiving end of wireless power transmission systems. It has the characteristics of simple design, the largest area enclosed with the same amount of wire, and light weight.

[0051] like Figure 3 As shown, the transmitting end fan-loop coil unit adopts a planar spiral structure, and the outermost large circular arc radius of the fan-loop coil unit is... The radius of the small arc is Number of turns The central angle corresponding to the fan-ring coil unit is The interval between each sector coil unit corresponds to an angle of , It can be a negative value, meaning adjacent sector coil units overlap, or it can be a positive value. The radius of the outermost turn of the lower-layer circular ring coil at the transmitter is... Number of turns The inter-turn distance of the sector ring coil unit and the lower ring coil of the transmitter is... The radius of the outermost turn of the receiving end circular coil is... Number of turns The distance between turns is The vertical height between the transmitting coil assembly and the receiving end circular coil is... .

[0052] This invention also proposes a wireless power transfer system based on a multi-coil combination at the transmitter. The system includes the aforementioned magnetic coupling mechanism, transmitter, and receiver. The transmitter includes a transmitter DC power supply, a transmitter full-bridge inverter, and a transmitter resonant network connected in sequence, with the transmitter resonant network connected to the transmitter magnetic coupling mechanism. The receiver includes a receiver resonant network, a receiver full-bridge rectifier module, and a receiver battery load connected in sequence, with the receiver resonant network connected to the receiver magnetic coupling mechanism.

[0053] When a traditional single circular coil operates as the transmitter in a wireless power transmission system, there is good magnetic field coupling between the transmitter and receiver in the central region of the coil. However, as the position of the receiver coil changes, the magnetic field coupling between the transmitting and receiving coils fluctuates significantly, thus substantially affecting the system's transmission power and efficiency. Although increasing the size of the transmitter coil can increase the mutual inductance stability region, simply increasing the transmitter size is not only space-consuming but also uneconomical. Therefore, when the size of the transmitter coil is limited, optimizing its design to improve the system's anti-migration performance is of great importance.

[0054] Sector-ring coils can generate good magnetic field coupling with the receiving coil in the middle region of the sector ring. When multiple sector-ring coil units are arranged in a plane at certain intervals to form a planar ring, the mutual inductance between the sector-ring coil array and the receiving coil is relatively high in the area covered by the sector-ring coil array. Each sector-ring coil unit has The mutual inductance peak is high; however, the mutual inductance level between the fan-ring coil array and the receiving coil is low in the central hollow region of the fan-ring coil array.

[0055] Therefore, this invention employs a transmitting-end magnetic coupling mechanism that combines a fan-ring coil array with a circular coil. The circular coil array provides the main mutual inductance at the center of the wireless power transmission area, while the fan-ring coil array provides the mutual inductance outside the center of the wireless power transmission area. Due to the low mutual inductance level at the hollow area at the center of the fan-ring coil array, the magnetic coupling mechanism combining the circular coil and the fan-ring coil array can achieve a large area of ​​power stability in the wireless power transmission area. The fan-ring coil array can compensate for the reduced mutual inductance caused by the positional shift of the circular coil portion. The overall combined magnetic coupling mechanism has continuous mutual inductance compensation characteristics.

[0056] To quantify the fluctuation of the mutual inductance between the transmitting and receiving coils with changes in the receiver's position, the following method was used: Indicates the radial offset of the receiver at the point of contact. The fluctuation rate of mutual inductance within the range. The radial displacement of the receiving coil center within... During the variation within the range, the maximum and minimum values ​​of mutual inductance are respectively expressed as: and , Represented as:

[0057] ,

[0058] To ensure stable system output when the receiving coil experiences a positional shift, Smaller values ​​are more conducive to reducing the difficulty of stable control of the system at the transmitting or receiving end. At a certain time, The larger the value, the better the anti-offset performance of the magnetic coupling mechanism.

[0059] With the outer radius of a single circular transmitting coil Number of turns outer radius of the circular receiving coil , Transmission distance mutual inductance volatility Taking parameter design as an example, the mutual inductance characteristics between a single circular ring transmitting coil and a circular ring receiving coil are calculated. The results are as follows: Figure 4 As shown, the maximum offset corresponds to the mutual inductance transformation characteristic in this calculation example. It is 0.08m.

[0060] With identical receiver parameters, the mutual inductance between the transmitter and receiver is closely related to the transmitter parameters. In the case of commonly used circular planar helical transmitting coils, load movement leads to significant fluctuations in system transmission performance. Given the same maximum outer radius limitation at the transmitter, optimizing the changes in key parameters of the fan-loop coil array improves overall offset resistance and increases tolerance to receiver position offset.

[0061] The anti-offset design method proposed in this invention includes mutual inductance calculation of the magnetic coupling mechanism of the multi-sector coil combination at the transmitter end and multi-parameter optimization of the sector coil unit at the transmitter end.

[0062] Figure 3 The actual winding diagram of the sector-ring coil unit is shown below. To analyze the mutual inductance variation characteristics of the magnetic coupling mechanism based on the sector-ring coil array, the actual coil unit winding can be approximately simplified as follows: Figure 5 The diagram shows a closed sector loop assembly; the receiving end adopts a planar spiral coil structure, which can be approximately equivalent to... Figure 6 The closed circular coil clusters with decreasing radii shown are approximated using reasonable equivalence to reduce the complexity of subsequent mutual inductance calculations. A schematic diagram illustrating the mutual inductance calculation between the transmitting-end fan-loop coil unit and the receiving-end planar spiral coil is shown below. Figure 6 As shown. Figure 6 middle, Indicates the fan-ring coil unit number vertex of the turn , and Represents vertices of Axis coordinates and The coordinates of the axes are the same for the other vertices. This indicates the center of the circular receiving coil. and express of Axis coordinates and Axis coordinates. Indicates the first The first sector coil unit Line segment infinitesimal element on the turn, Indicates the receiving coil number The line segment element on the turn.

[0063] like Figure 6 As shown, the first The first sector coil unit Turn circuit and receiving coil Turn circuit The mutual induction between them is:

[0064] ,

[0065] Sector-ring coil unit A turn can be decomposed into arc segments. and and straight line segments and Four-segment radial segmented micro-element.

[0066] according to Figure 5 and Figure 6 As shown, the first outer arc segment of the turn loop radius:

[0067] ,

[0068] No. inner arc segment of the turn loop radius:

[0069] ,

[0070] point of Directional coordinates are represented as:

[0071] ,

[0072] and The included angle along the axial direction is expressed as:

[0073] .

[0074] Similarly, the calculation yields... Figure 6 Key points Connect the origin and Axis angle The calculation expression:

[0075] ,

[0076] The coordinates of each key point are then obtained:

[0077] .

[0078] The first ring receiving coil Radius of the turn loop:

[0079] ,

[0080] arc segment With the receiving coil The mutual inductance of a circular loop is represented as:

[0081] ,

[0082] straight segment With the receiving end Mutual inductance of circular loops:

[0083] ,

[0084] arc segment With the receiving end Mutual inductance of circular loops:

[0085] ,

[0086] straight segment With the receiving end Mutual inductance of circular loops:

[0087] ,

[0088] therefore, This can be represented as each line segment and the receiving end... Superposition of mutual inductance in circular loops:

[0089] .

[0090] according to Figure 6 The diagram showing mutual inductance calculation is shown in the figure. The mutual inductance between the sector loop coil unit and the receiving coil is represented as follows:

[0091] .

[0092] like Figure 1 As shown, Each sector-ring coil unit is connected in series. Using the mutual inductance calculation formula between the circular transmitting and receiving coils, the mutual inductance at the transmitting and receiving ends of the proposed magnetic coupling mechanism can be expressed as:

[0093] .

[0094] The mutual inductance between the sector loop coil array and the receiving coil varies with position, exhibiting a curved surface characteristic. A hump. As the number of sector-ring coils increases, the upper part of the mutual inductance surface between the sector-ring coil array and the receiving coil becomes smoother, which is more conducive to improving the overall mutual inductance stability of the transmitting coil assembly and the receiving coil. As the number of sector-ring coils increases, the amount of wire used in the transmitting coil array also increases. This invention selects a sector-ring coil number of [number missing]. Further research is needed on optimization schemes for the sector loop coil parameters.

[0095] The amount of wire used for winding the transmitting coil provided by this invention can be expressed as:

[0096] ,

[0097] in, and Represents the two straight sides of the sector loop coil element and the coordinate system The included angle of the axis, This indicates the length of the straight side of the sector loop coil unit. , , The radii of each circle are calculated based on known parameters by establishing a rectangular coordinate system.

[0098] Optimizing a sector ring coil array involves parameters such as the maximum outer radius, minimum inner radius, number of coil turns, and coil apex angle.

[0099] As the outer radius of the sector loop coil increases, the peak point of the sector loop coil array becomes higher and farther from the center. Under the same mutual inductance fluctuation limit, a larger outer radius of the sector loop coil allows for greater lateral offset. The maximum radius of the sector loop coil does not exceed the finite maximum size of the overall transmitter.

[0100] As the inner radius of the sector loop coil increases, the mutual inductance between the sector loop coil array and the receiving coil gradually decreases when the receiving coil is in the aligned position, thus gradually reducing the total mutual inductance at the transmitting and receiving ends. As the inner radius of the sector loop coil increases, the peak point of the mutual inductance curve of the sector loop coil array shifts outwards, but the value gradually decreases.

[0101] As the number of turns in the sector loop coil increases, the mutual inductance between the sector loop coil array and the receiving coil gradually increases when the receiving coil is in the aligned position, and consequently, the total mutual inductance at the transmitting and receiving ends also gradually increases. As the number of turns in the sector loop coil increases, the peak values ​​of the mutual inductance between the sector loop coil array and the receiving coil appear at almost the same positions, and the maximum values ​​gradually increase.

[0102] The total mutual inductance characteristic curve of the transmitting and receiving ends is also affected by the size of the apex angle of the fan-ring coil, corresponding to different maximum offset distances and mutual inductance levels at the facing positions.

[0103] Based on the above analysis, the fan-ring coil array has a certain effect on improving the stability of the mutual inductance and anti-offset performance of the transceiver coils. Under the premise that the receiver parameters and vertical distance remain unchanged, the improvement in the stability of the mutual inductance and anti-offset performance of the transceiver coils is affected by factors such as the large arc radius, small arc radius, number of coil turns, and apex angle of the fan-ring coil array. In the aforementioned analysis, the larger the large arc radius of the fan-ring coil array, the better the anti-offset performance. Therefore, without exceeding the maximum transmitter size limit, the large arc radius of the fan-ring coil array is selected to be the same as that of the bottom circular coil. For the optimization of other parameters, the multi-parameter optimization method flow of the transmitter fan-ring coil in the anti-offset design provided in this invention example is as follows: Figure 7 As shown.

[0104] The multi-parameter optimization method for the transmitter fan-loop coil provided by this invention has the following steps:

[0105] (a) Determine the outermost turn radius of the bottom circular coil of the transmitter. Number of turns and the outer radius of the circular coil at the receiving end Number of turns and transmission height ;

[0106] (ii) Determining the mutual inductance volatility limit axial offset distance step size The radius of the receiving end circular coil is... Axis angle Change step size ;

[0107] (III) Determine the range of the multiple parameters to be optimized, where the parameter to be optimized is the small arc radius of the fan-loop coil unit. Number of turns per fan-ring coil unit Corresponding vertex of the fan-ring coil unit ;

[0108] (iv) Determine the current calculation parameters , and ,in, , , ;

[0109] (v) Based on the mutual inductance calculation method in anti-offset design, change the axial offset distance between the receiving coil and the transmitting coil. And changing the radius of the receiving coil at the same axial offset distance Angle between axes And calculate the mutual inductance value. , This indicates the mutual inductance between the transmitting and receiving magnetic coupling mechanisms;

[0110] (vi) Calculation of mutual inductance fluctuations If mutual inductance fluctuations satisfy Then record The maximum axial offset distance is recorded. , and If the above conditions are not met, return to step (v) and recalculate;

[0111] (vii) If satisfied Then select the maximum axial offset distance. The maximum value, and based on the corresponding multiple parameters. , and Value calculation of the amount of wiring used for transmitting end processing , Indicates parameters , and The amount of wire used at that time;

[0112] (viii) Further select the minimum value of the amount of thread used. ;

[0113] (ix) Output the corresponding , and The fan-ring coil unit designed based on the optimized parameters has the advantages of using less wire and smaller mutual inductance fluctuation amplitude, which is beneficial to the overall wireless power transmission performance of the magnetic coupling mechanism.

[0114] Taking the following parameter design as an example, perform multi-parameter optimization calculations for the transmitter fan-loop coil:

[0115] transmitter outer radius size limit Mutual inductance volatility limit Axial offset step size The radius of the transmitting coil and The step size of the axis angle variation .

[0116] inner diameter of fan-ring coil unit scope Number of turns per fan-ring coil unit scope The apex of the fan-ring coil unit scope axial offset scope The radius of the transmitting coil and Axis angle scope .

[0117] Based on the above-described multi-parameter optimization process for the transmitter fan-loop coil and the aforementioned calculations, the optimized parameters are obtained. , Turns, .

[0118] The surface plots of mutual inductance change characteristics corresponding to different position angle changes under the optimized parameters are as follows: Figure 8 As shown.

[0119] Comparison of the mutual inductance characteristic curves of the multi-coil combination of the transmitter after multi-parameter optimization and that of a single circular transmitter coil. Figure 9 As shown, when the mutual inductance fluctuation rate does not exceed 5%, the maximum offset distance of the circular transmitting coil is 0.08m, and the maximum offset distance of the proposed transmitting coil is 0.12m, which effectively improves the anti-offset performance of the system.

[0120] Taking the following parameters as an example: the outer radius of the circular transmitting coil is 0.2m, and the number of turns is 20. The outer radius of the fan-shaped coil unit is 0.2m, the inner radius is 0.10m, and the number of turns is 10. The outer radius of the receiving coil is 0.1m, and the number of turns is 20. All coils are tightly wound with a wire diameter of 0.003m. The vertical distance between the transmitting and receiving ends is 0.08m.

[0121] The mutual inductance between the transmitting and receiving coils is calculated by measuring the forward and reverse series inductances of the transmitting and receiving coils using an LCR meter. Regardless of whether it is a single circular transmitting coil or the proposed optimized transmitting coil structure, the mutual inductance remains constant at different angles within a 360° range in the plane when the offset distance is the same. Figure 10 The inductance measurement of a single circular transmitting coil as a function of position offset. Figure 11 The inductance measurement value of the proposed transmitting coil assembly is given by the characteristic of position offset. Figure 12 The mutual inductance characteristics of a single circular transmitter and the proposed transmitter coil combination with the same receiver coil as a function of position offset were calculated. For a single circular transmitter coil at the transmitter, with a mutual inductance fluctuation limit of 5%, the corresponding maximum offset distance is 8 cm. For the proposed coil structure at the transmitter, under the same mutual inductance fluctuation limit, the corresponding maximum offset distance is 12 cm. The proposed magnetic coupling mechanism with a multi-coil combination at the transmitter, optimized for anti-offset design, shows a 50% improvement in maximum offset distance compared to a single circular transmitter magnetic coupling mechanism with the same external dimensions, under the same receiver conditions.

[0122] Based on the same inventive concept, embodiments of this application provide a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the aforementioned anti-offset design method.

[0123] Based on the same inventive concept, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the aforementioned anti-offset design method.

[0124] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0125] This invention is described with reference to flowchart illustrations of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each step in the flowchart, and combinations of steps in the flowchart, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing device, generate instructions for implementing the steps in the flowchart. Figure 1 A device for a function specified in one or more processes.

[0126] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 The function specified in one or more processes.

[0127] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 Steps of a specified function in one or more processes.

[0128] The above embodiments are merely illustrative of the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solutions based on the technical concept proposed in this invention shall fall within the scope of protection of this invention.

Claims

1. A method for anti-offset design of magnetic coupling mechanisms in wireless power transmission systems, characterized in that, The magnetic coupling mechanism includes a transmitting magnetic coupling mechanism and a receiving magnetic coupling mechanism for realizing wireless power transmission. The transmitting magnetic coupling mechanism includes upper and lower coils. The lower coil is a circular ring coil, and the upper coil is a fan-ring coil array. The upper coil is disposed on the upper surface of the lower coil. The fan-ring coil array includes multiple fan-ring coil units disposed on the same plane. The multiple fan-ring coil units are evenly arranged circumferentially around the same common central axis. The outer diameter of the fan-ring coil array is equal to the outer diameter of the lower circular ring coil. All fan-ring coil units are connected in series, and the fan-ring coil array is connected in series with the lower circular ring coil. The receiving end magnetic coupling mechanism includes a receiving end circular coil, which is arranged parallel to and directly opposite the fan-ring coil array. The anti-offset design method includes the following steps: Step 1: Given the outermost turn radius of the lower-level circular coil at the transmitter. and number of turns The outermost turn radius of the receiving end circular coil and number of turns And the vertical height between the transmitting end magnetic coupling mechanism and the receiving end magnetic coupling mechanism. ; Step 2, preset mutual inductance volatility limit axial offset distance Step size of change and the radius of the receiving end circular coil and the spatial rectangular coordinate system Axis angle Step size of change The spatial rectangular coordinate system has its origin at the center of the lower-layer annular coil of the transmitter. The plane is the plane where the lower ring coil of the transmitter is located. The axis is oriented in the direction of the receiving end's circular coil; initially, the axial offset distance... The value is 0, and the radius of the receiving end circular coil is relative to the spatial rectangular coordinate system. Axis angle =0; Step 3: Determine the value range of the parameters to be optimized in the anti-offset design, and number each parameter starting from 1. The parameters to be optimized include the small arc radius of the fan-ring coil unit. Number of turns in a fan-shaped coil unit and the corresponding central angle of the fan-ring coil unit ,in, , and All represent numbers. , , , , and These are the small arc radius of the fan-ring coil unit, the number of turns of the fan-ring coil unit, and the number of all numbers corresponding to the central angle of the fan-ring coil unit; Step 4: Iterate through all combinations of parameters to be optimized. In each combination, starting from 0, proceed according to the step size. Change the axial offset distance between the receiver's ring coil and the transmitter's lower ring coil. And at the same axial offset distance, starting from 0 according to the step size Changing the radius of the receiving end's circular coil relative to the spatial rectangular coordinate system Axis angle , The maximum value is , The maximum value is ; Step 5, at the current axial offset distance corresponding to the current combination. Down, included angle Each time a change is made, the mutual inductance between the corresponding transmitting and receiving magnetic coupling mechanisms is calculated. Find the maximum and minimum values ​​of all mutual inductances at the current axial offset distance, and calculate the mutual inductance fluctuation. ; Step 6: Determine whether the mutual inductance fluctuation corresponding to the current axial offset distance is greater than the mutual inductance fluctuation rate limit. If so, then the previous axial offset distance is taken as the maximum axial offset distance of the current combination; otherwise, the current axial offset distance is increased by one step. , as the new current axial offset distance and return to step 5; Step 7: Based on Steps 4-6, find the maximum axial offset distance for each combination. Find the maximum value among all the maximum axial offset distances. If there is only one maximum value, take the combination corresponding to the maximum value as the optimal parameter combination; otherwise, proceed to Step 8. Step 8: If there are at least two maximum values, calculate the amount of wire used for winding the transmitter magnetic coupling mechanism under the combination corresponding to each maximum value, and select the combination with the minimum amount of wire used as the optimal parameter combination.

2. The anti-offset design method for a magnetic coupling mechanism in a wireless power transmission system according to claim 1, characterized in that, The fan-shaped coil unit uses a planar helical structure to wind the coil.

3. The anti-offset design method for a magnetic coupling mechanism in a wireless power transmission system according to claim 1, characterized in that, In the sector ring coil array, the included angles between the axes of symmetry of adjacent sector ring coil units are equal. When the number of sector ring coil units is... At that time, the included angle between the axes of symmetry of adjacent sector coil units is , Is a positive integer.

4. The anti-offset design method for the magnetic coupling mechanism of a wireless power transmission system according to claim 1, characterized in that, The formula for calculating the mutual inductance fluctuation is as follows: in, , The included angles are the current axial offset distances. From 0 to The maximum and minimum values ​​among all mutual inductances; Mutual inductance between the transmitting and receiving magnetic coupling mechanisms The calculation formula is as follows: in, This refers to the number of fan-ring coil units. For the first k The mutual inductance of each sector-ring coil unit to the magnetic coupling mechanism at the receiving end. This represents the mutual inductance between the lower-level annular coil at the transmitting end and the magnetic coupling mechanism at the receiving end. The number of turns of the fan-ring coil unit. For the first k The first sector coil unit The first turn of the receiving end circular coil Mutual inductance of turns, The lower ring coil of the transmitting end The first turn of the receiving end circular coil Mutual inductance of turns.

5. The anti-offset design method for a magnetic coupling mechanism in a wireless power transmission system according to claim 1, characterized in that, The formula for calculating the amount of wire used in the coil winding of the transmitting end magnetic coupling mechanism is as follows: in, This refers to the amount of wire used for winding the coil of the magnetic coupling mechanism at the transmitting end. This refers to the number of fan-ring coil units. The number of turns of the fan-ring coil unit. For the central angle corresponding to the fan-ring coil unit, and These are the two straight sides of the fan-shaped coil unit and the coordinate system, respectively. The included angle of the axis, , These are the fan-ring coil units. Larger and smaller arc radii , Let be the length of the straight side of the sector loop coil unit. , The lower ring coil of the transmitting end The radius of the circle corresponding to the turn. This refers to the turn-to-turn distance of the lower-layer annular coil at the transmitting end.

6. A wireless power transmission system based on the anti-offset design method for the magnetic coupling mechanism of a wireless power transmission system according to any one of claims 1-5, characterized in that, The wireless power transmission system includes a magnetic coupling mechanism for the wireless power transmission system, as well as a transmitter and a receiver. The transmitter includes a transmitter DC power supply, a transmitter full-bridge inverter, and a transmitter resonant network connected in sequence. The transmitter resonant network is connected to the transmitter magnetic coupling mechanism. The receiver includes a receiver resonant network, a receiver full-bridge rectifier module, and a receiver battery load connected in sequence. The receiver resonant network is connected to the receiver magnetic coupling mechanism.

7. A computer device comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the anti-offset design method for a magnetic coupling mechanism for a wireless power transmission system as described in any one of claims 1 to 5.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the anti-offset design method for the magnetic coupling mechanism of a wireless power transmission system as described in any one of claims 1 to 5.

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