Three-phase electromagnetic coupling mechanism and wireless power transmission system

Abstract

The invention provides a three-phase electromagnetic coupling mechanism and a wireless power transmission system, and relates to the technical field of wireless power transmission. The three-phase electromagnetic coupling mechanism comprises a magnetic core layer, an A-phase coil, a B-phase coil and a C-phase coil, wherein the A-phase coil, the B-phase coil and the C-phase coil are arranged on the magnetic core layer in a stacked mode and form a three-layer stacked structure. The A-phase coil, the B-phase coil and the C-phase coil respectively comprise two coil sections which are electrically connected, each coil section covers a 180-degree corresponding area in the circumferential direction of the magnetic core layer, and orthographic projections of the two coil sections of each phase coil on the magnetic core layer are in central symmetry; and each layer of the three-layer laminated structure is provided with coil parts of coil sections of at least two different-phase coils. Multi-layer participation and symmetrical coverage of the three-phase coils are realized in the three-layer laminated structure, and each layer comprises different-phase coil sections, so that the problems of low space utilization rate and non-uniform magnetic field of a planar structure are effectively solved, and the magnetic coupling stability and the power transmission performance are improved.

Description

A three-phase electromagnetic coupling mechanism and a wireless power transfer system Technical Field

[0001] This invention relates to the field of wireless power transmission technology, and more specifically, to a three-phase electromagnetic coupling mechanism and a wireless power transmission system. Background Technology

[0002] Wireless Power Transfer (WPT) technology relies on magnetic field coupling between the transmitting and receiving sides to achieve the wireless and contactless transfer of electrical energy.

[0003] In current wireless power transmission applications, single-phase coils are mostly used to transmit or receive electrical energy. However, the magnetic field generated by a single-phase coil is pulsating, with limited flux coverage. The magnetic coupling capability fluctuates significantly with changes in the relative positions of the coils, resulting in limited power density, weak anti-offset capability, and insufficient transmission stability. To address this, related technologies have attempted to use three-phase coil structures to generate a rotating magnetic field, making the magnetic field distribution more uniform and enhancing anti-offset capability. However, existing three-phase coil structures often employ planar arrangements or simple stacking, limiting the spatial participation of each phase coil in the vertical direction. This makes it difficult to effectively utilize the three-dimensional space near the core layer, resulting in an uneven magnetic field distribution across different height planes for each phase coil. This easily leads to localized flux accumulation or weakening areas, thus limiting the magnetic coupling performance and power transmission capabilities of the three-phase coil structure. Summary of the Invention

[0004] The problem this invention addresses is: how to improve the power transmission performance of wireless power transmission processes.

[0005] To address the above problems, the present invention provides a three-phase electromagnetic coupling mechanism and a wireless power transmission system.

[0006] In a first aspect, the present invention provides a three-phase electromagnetic coupling mechanism, comprising a magnetic core layer and an A-phase coil, a B-phase coil, and a C-phase coil stacked on the magnetic core layer, wherein the A-phase coil, the B-phase coil, and the C-phase coil form a three-layer stacked structure; each of the A-phase coil, the B-phase coil, and the C-phase coil comprises two electrically connected coil segments, each coil segment covering a 180° corresponding area along the circumference of the magnetic core layer, and the orthographic projections of the two coil segments of each phase coil on the magnetic core layer are centrally symmetrical; each layer of the three-layer stacked structure is provided with coil portions of at least two coil segments of different phase coils.

[0007] Optionally, the A-phase coil, the B-phase coil, and the C-phase coil have the same orthographic projection shape on the magnetic core layer, and are deflected by 120° in sequence.

[0008] Optionally, the orthographic projection of each coil segment onto the magnetic core layer is semi-circular, and each coil portion is fan-shaped.

[0009] Optionally, the same coil segment is bent and transitioned between the coil portions of different layers of the three-layer stacked structure.

[0010] Optionally, the average distance from each phase coil to the core layer is equal, and the average distance is the weighted average of the distances from the coil portion of the coil segment in each layer of the three-layer stacked structure to the core layer.

[0011] Optionally, the weight of the weighted average is determined based on the proportion of the coil portion of the coil segment in each layer of the three-layer stacked structure that covers the circumferential area of ​​the magnetic core layer.

[0012] Optionally, for one of the three phases (A-phase, B-phase, and C-phase), two coil segments are respectively distributed in the first and third layers of the three-layer stacked structure; for another coil segment, one-third of its coil portion is distributed in the first layer and two-thirds of its coil portion is distributed in the second layer of the three-layer stacked structure; for yet another coil segment, one-third of its coil portion is distributed in the third layer and two-thirds of its coil portion is distributed in the second layer; for yet another coil segment, one-third of its coil portion is distributed in the first layer, one-third of its coil portion is distributed in the second layer, and one-third of its coil portion is distributed in the third layer; for yet another coil segment, one-third of its coil portion is distributed in the first layer, one-third of its coil portion is distributed in the second layer, and one-third of its coil portion is distributed in the third layer.

[0013] In a second aspect, the present invention also provides a wireless power transmission system, including a wireless power transmitting mechanism and a wireless power receiving mechanism, wherein at least one of the wireless power transmitting mechanism and the wireless power receiving mechanism includes a three-phase electromagnetic coupling mechanism as described in the first aspect.

[0014] Optionally, the wireless power transmission mechanism includes a first three-phase electromagnetic coupling mechanism, a primary-side resonant mechanism, a three-phase inverter, and a DC power supply, wherein the DC power supply, the three-phase inverter, the primary-side resonant mechanism, and the first three-phase electromagnetic coupling mechanism are electrically connected in sequence.

[0015] Optionally, the wireless power transmitting mechanism includes a second three-phase electromagnetic coupling mechanism, a secondary resonant mechanism, and a three-phase rectifier, wherein the second three-phase electromagnetic coupling mechanism, the secondary resonant mechanism, and the three-phase rectifier are electrically connected in sequence.

[0016] The beneficial effects of the three-phase electromagnetic coupling mechanism and wireless power transmission system of the present invention are as follows: The three-phase electromagnetic coupling mechanism of the present invention constructs a three-layer stacked structure with a first layer, a second layer, and a third layer along the vertical direction on the magnetic core layer, so that the A-phase coil, B-phase coil, and C-phase coil all participate in the establishment of the magnetic field in a multi-layer manner. Furthermore, by constructing a structure in which each phase consists of two coil segments covering 180° circumferentially, and the orthographic projections of the two coil segments on the magnetic core layer are centrally symmetrical, a continuous and symmetrical magnetic field distribution in the circumferential direction is achieved. Simultaneously, each layer of the three-layer stacked structure contains coil portions of at least two different phase coils, ensuring that each layer plays an effective role in the formation of magnetic flux and magnetic field coupling. With the above structural configuration, the coverage capability of the three-phase coils in three-dimensional space is significantly enhanced, overcoming the problems of insufficient space utilization, limited vertical magnetic field participation, and uneven distribution of planar magnetic fields at different heights caused by the planar or simple stacking methods of existing three-phase coils. This makes the propagation of the magnetic field between the three layers more continuous and balanced, thereby improving the overall stability and effectiveness of magnetic coupling and enhancing the magnetic coupling performance and power transmission performance in the wireless power transmission process. Attached Figure Description

[0017] Figure 1 is a structural schematic diagram of the three-phase electromagnetic coupling mechanism in an embodiment of the present invention; Figure 2 is an exploded structural schematic diagram of the three-phase electromagnetic coupling mechanism in an embodiment of the present invention; Figure 3 is a structural schematic diagram of the three-phase electromagnetic coupling mechanism from another perspective in an embodiment of the present invention; Figure 4 is a structural schematic diagram of the A-phase coil, B-phase coil, and C-phase coil in an embodiment of the present invention; Figure 5 is a structural schematic diagram of the wireless power transmission system in an embodiment of the present invention; Figure 6 is a structural schematic diagram of the wireless power transmitting mechanism and the wireless power receiving mechanism, both of which employ a three-phase electromagnetic coupling mechanism in an embodiment of the present invention.

[0018] Reference numerals in the attached diagram: 1. Phase A coil; 2. Phase B coil; 3. Phase C coil; 4. Magnetic core layer; 5. Wireless power transmitting mechanism; 51. First three-phase electromagnetic coupling mechanism; 52. Primary-side resonant mechanism; 53. Three-phase inverter; 54. DC power supply; 6. Wireless power receiving mechanism; 61. Second three-phase electromagnetic coupling mechanism; 62. Secondary-side resonant mechanism; 63. Three-phase rectifier; 7. Load. Detailed Implementation

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in sequences other than those illustrated or described herein.

[0021] Referring to Figures 1 and 2, this embodiment of the invention provides a three-phase electromagnetic coupling mechanism, including a magnetic core layer 4 and an A-phase coil 1, a B-phase coil 2, and a C-phase coil 3 stacked on the magnetic core layer 4, forming a three-layer stacked structure; each of the A-phase coil 1, B-phase coil 2, and C-phase coil 3 includes two electrically connected coil segments, each coil segment covering a corresponding area of ​​180° along the circumference of the magnetic core layer 4, and the orthographic projections of the two coil segments of each phase coil on the magnetic core layer 4 are centrally symmetrical; each layer of the three-layer stacked structure has coil portions of at least two coil segments of different phase coils.

[0022] In this embodiment, the three-phase electromagnetic coupling mechanism can be applied to the wireless power transmitting mechanism 5 and / or the wireless power receiving mechanism 6 of the wireless power transmission system to improve the efficiency and stability of wireless power transmission between the wireless power transmitting mechanism 5 and the wireless power receiving mechanism 6.

[0023] The three-phase electromagnetic coupling mechanism includes a magnetic core layer 4 and three-phase coils (i.e., phase A coil 1, phase B coil 2, and phase C coil 3) disposed on the magnetic core layer 4. The three-phase coils are stacked in multiple layers in the vertical direction relative to the magnetic core layer 4, forming an overall stacked coil structure with a first layer, a second layer, and a third layer (denoted as a three-layer stacked structure). The magnetic core layer 4 provides a magnetic flux channel for the three-phase electromagnetic coupling mechanism, and the magnetic fields generated by each phase coil during operation are coupled through the magnetic core layer 4. In order to effectively utilize the three-dimensional space of the three-layer stacked structure and improve the magnetic field coverage capability of the three-phase coils in this three-dimensional space, each phase coil has coil portions distributed in different layers. That is, the coil structure of the same phase coil occupies at least two different layers in the vertical direction simultaneously, so that each phase coil has multi-layer distribution characteristics in the three-layer stacked structure.

[0024] Specifically, phase A coil 1, phase B coil 2, and phase C coil 3 each consist of two electrically connected coil segments (or each phase coil is wound with a single excitation wire, forming two coil segments). Each coil segment extends circumferentially along the core layer 4, covering a circumferential range corresponding to a 180° region. The orthographic projections of the two coil segments of each phase coil onto the core layer 4 are centrally symmetrical, thus geometrically forming a complete loop structure that fully covers the core layer 4. In this structure, since the two coil segments of each phase coil have the same circumferential coverage and are located in opposite circumferential regions, the closed loop formed by the electrical connection can generate magnetic flux distributions in opposite directions during operation, thereby constituting a bipolar magnetic field. Simultaneously, because the orthographic projections of the two coil segments onto the core layer 4 are centrally symmetrical, the magnetic field distribution of the coils in the circumferential direction has mirror consistency, forming a stable bipolar structure without depending on the specific shape of the coil segments. In this way, each phase coil achieves spatial magnetic field balance through the orthographically symmetrical double-coil segment structure, enabling the coil to obtain a symmetrical magnetic coupling path in the circumferential direction. This is beneficial for maintaining the magnetic field symmetry and equivalent magnetic circuit consistency between phases in a three-phase electromagnetic coupling mechanism, while providing a stable basic structure for the coupling of the three-phase coils and the magnetic core layer 4. Furthermore, this centrally symmetrical double-coil segment structure is applicable to various coil shapes, including circular, elliptical, or other circumferentially extended shapes, thus providing greater flexibility for engineering design.

[0025] Furthermore, to ensure uniform magnetic coupling characteristics of the three-phase coils in a multi-layered structure, each layer of the three-layer stacked structure contains coil portions from at least two coil segments of different phase coils. This means that each layer simultaneously contains coil portions of at least two of the phase coils: A-phase coil 1, B-phase coil 2, and C-phase coil 3. This ensures that each layer of the three-layer stacked structure consistently performs the coupling function of multi-phase magnetic fields, thus avoiding a single-phase coil occupying the space of a particular layer and improving the space utilization efficiency near the core layer 4. Since each phase coil includes two coil segments, each coil segment can be placed in at least one layer according to structural layout requirements. By distributing the corresponding coil portions of different phase coil segments within the same layer, this layer can simultaneously participate in the establishment of magnetic fields for multiple phases during electromagnetic coupling, helping to create overlapping magnetic field coverage areas between different layers of the three-phase coils. By employing this multi-layered arrangement and a mixed, staggered distribution of multi-phase coils within the same layer, each layer of the three-layer stacked structure is associated with at least two phase coils. The three-phase coils achieve higher coverage in both the circumferential and vertical directions of the core layer, enabling a more structurally balanced coil distribution during operation. This enhances the overall electromagnetic coupling participation, providing a spatial basis for achieving a more balanced magnetic field distribution and more stable magnetic coupling performance. Furthermore, each layer of the three-layer stacked structure plays a role in magnetic flux distribution, magnetic flux transmission paths, and electromagnetic coupling relationships. Each layer of the three-layer stacked structure bears the magnetic field influence from different phase coils, avoiding situations where a single layer only participates in the magnetic coupling of a single phase coil. This improves the overall magnetic flux continuity of the three-phase coils in the multi-layered structure, and the superposition and transmission of magnetic fields in each layer are more balanced, facilitating a more uniform and stable magnetic coupling relationship between the three-phase coils. Simultaneously, it provides a favorable foundation for achieving self-inductance consistency, inter-phase mutual inductance coordination, and overall electromagnetic symmetry in the three-phase electromagnetic coupling mechanism.

[0026] In summary, the three-phase electromagnetic coupling mechanism of this embodiment constructs a three-layer stacked structure with a first layer, a second layer, and a third layer along the vertical direction on the magnetic core layer 4. This allows phase A coil 1, phase B coil 2, and phase C coil 3 to participate in magnetic field establishment in a multi-layer manner. Furthermore, each phase consists of two coil segments covering 180° circumferentially, and the orthographic projections of these two coil segments onto the magnetic core layer 4 are centrally symmetrical, achieving a continuous and symmetrical magnetic field distribution in the circumferential direction. Simultaneously, each layer of the three-layer stacked structure contains coil portions of at least two different phases, ensuring that each layer plays an effective role in flux formation and magnetic field coupling. With this structural configuration, the coverage capability of the three-phase coils in three-dimensional space is significantly enhanced. This overcomes the problems of insufficient space utilization, limited vertical magnetic field participation, and uneven distribution of planar magnetic fields at different heights caused by the planar or simple stacking methods of existing three-phase coils. The propagation of the magnetic field between the three layers is more continuous and balanced, thereby improving the overall stability and effectiveness of magnetic coupling and enhancing magnetic coupling performance and power transmission during wireless power transmission.

[0027] Optionally, as shown in Figures 1 and 3, the orthographic projections of phase A coil 1, phase B coil 2, and phase C coil 3 on the magnetic core layer 4 have the same shape and are deflected by 120° in sequence.

[0028] In this embodiment, the orthographic projections of phase A coil 1, phase B coil 2, and phase C coil 3 on the core layer 4 are identical. For example, when observing each phase coil from a top-down perspective, the geometric contours of the three phase coils are consistent, all having the same circumferential extension path and the same outer boundary, thus presenting the same structural shape in the planar direction. Based on this, the three phase coils can be arranged relative to each other by circumferential rotation, such that the orthographic projection of phase B coil 2 is deflected by 120° relative to the orthographic projection of phase A coil 1 in the circumferential direction, and the orthographic projection of phase C coil 3 is further deflected by 120° relative to the orthographic projection of phase B coil 2, thereby forming a 120° circumferential deflection relationship in the orthographic projections of the three phase coils on the core layer 4. The deflection can be achieved by rotating the coils as a whole, without changing the shape or configuration of the coils themselves.

[0029] Thus, through the above arrangement, the three-phase coils occupy space evenly in the circumferential direction, which helps to make the magnetic field of the three-phase coils exhibit periodic distribution characteristics in the planar direction when the three-phase electromagnetic coupling mechanism is working, improves the spatial coupling consistency, enhances the overall symmetry, and provides favorable basic conditions for achieving balanced three-phase electromagnetic coupling characteristics.

[0030] Optionally, the orthographic projection of each coil segment onto the core layer 4 is a semicircle, and each coil portion is fan-shaped.

[0031] In this embodiment, the orthographic projections of each coil segment of phase A coil 1, phase B coil 2, and phase C coil 3 onto the core layer 4 are semi-circular. For example, when observing each phase coil from a top-down perspective, the projection area of ​​each coil segment covers a continuous 180° range in the circumferential direction of the core layer 4, forming a semi-circular arc-shaped plane projection that unfolds circumferentially. This semi-circular projection is determined by the winding path of the coil segment in space. Based on this, the orthographic projections of the coil portions in different layers onto the core layer 4 are fan-shaped, meaning each coil portion covers a fan-shaped area in the projection plane. The range covered by different coil portions in the circumferential direction may differ, therefore the central angle of the fan corresponding to each coil portion may also be different. For example, the ratio of the central angle corresponding to a coil portion to 360° can be used as its proportion in the circumferential coverage of the core layer 4. That is, if the central angle covered by a coil portion in the orthographic projection plane is θ, then the circumferential coverage proportion of that coil portion is θ / 360°. Therefore, the relative coverage of different coil parts in the circumferential direction can be represented in a unified geometric quantification method, providing a clear metric basis for subsequent calculations of coil part weights, evaluation of magnetic flux contribution, or other analyses based on circumferential coverage characteristics.

[0032] This allows the coil segments and their coil portions to have a clear coverage range in the planar direction, which is beneficial for uniformly describing each coil portion in subsequent implementation methods. It also facilitates the calculation and comparison of the coverage ratio of each coil portion in the circumferential direction, providing a clear geometric expression for the construction of the three-phase electromagnetic coupling mechanism.

[0033] Optionally, the same coil segment is bent and transitioned between coil portions of different layers in a three-layer stacked structure.

[0034] In this embodiment, to facilitate the distribution of the same coil segment across different layers, the coil segments are connected by bending transitions between their coil portions located on different layers. Specifically, when the coil portions of a certain coil segment are arranged on two or more different layers in a three-layer stacked structure, the coil segment can be continuously extended at the interlayer locations through bending, corner transitions, or spatial arc transitions, allowing the coil segment to cross different layers without interruption. For example, the coil segment can extend upward or downward from the coil portion located on the first layer along a vertical or oblique path, and continue to form the coil portion of the coil segment on the target layer after reaching the target layer, thereby maintaining the electrical continuity of the entire coil segment.

[0035] For example, referring to Figures 3 and 4, each phase coil consists of two coil segments distributed circumferentially in opposite positions, corresponding to the positive and negative polarity coil segments of that phase coil, respectively. In Figure 3 or 4, A+ represents the positive polarity coil segment of phase A coil 1, located in the right half of the illustrated circular area; while A- represents the negative polarity coil segment of phase A coil 1, located in the opposite half of the area where A+ is located. The two coil segments are continuously wound with a single wire and can be connected by bending to form a closed loop, so that the current flows in opposite directions in the two coil segments. When a working current is applied to phase A coil 1, the two coil segments A+ and A- generate magnetic flux distributions in opposite directions within their respective covered circumferential areas, thus forming a bipolar magnetic flux structure. Similarly, in Figure 3 or Figure 4, B+ and B- represent the positive and negative coil segments of phase B coil 2, respectively, arranged approximately 180° apart circumferentially, and their orthographic projections are also centrally symmetrical. C+ and C- correspond to the positive and negative coil segments of phase C coil 3, respectively, also exhibiting a circumferentially opposed structural feature. Since the positive and negative coil segments of each phase coil have the same circumferential coverage area and their projections on the core layer 4 are centrally symmetrically distributed, they can form bipolar magnetic fields with opposite directions and basically symmetrical amplitudes within their respective coverage areas during operation. This results in good mirror consistency of the magnetic flux distribution of the phase coil in the direction of the core layer 4, achieving a stable bipolar magnetic field effect regardless of the specific geometry of the coil segments. Furthermore, as shown in Figure 3 or Figure 4, the positive and negative polarity coil segments of each phase coil are arranged alternately in space and distributed along different layers in the three-phase stacked structure, so that the magnetic field contribution of the three-phase coils forms a complementary coverage in the circumferential direction. Through this arrangement, while maintaining the bipolar characteristics of each phase coil, the three-phase coils form a relatively balanced magnetic coupling distribution in the magnetic core layer 4, thereby further improving the stability and three-phase consistency of the electromagnetic coupling structure in actual operation.

[0036] Referring to Figures 3 and 4, Figure 4(a) shows the direction of magnetic flux coupling of phase A coil 1, Figure 4(b) shows the direction of magnetic flux coupling of phase B coil 2, and Figure 4(c) shows the direction of magnetic flux coupling of phase C coil 3. In Figures 4(a) to 4(c), the hollow arrows indicate the direction of magnetic flux generated by the corresponding positive and negative polarity coil segments under the driving current. When current flows continuously through the two coil segments of the corresponding phase coil along the conductor, the current flows in opposite directions in the two coil segments, thus forming a pair of opposite magnetic fluxes in the core layer 4 region, giving the phase coil a bipolar magnetic field characteristic. Therefore, the bipolar magnetic flux forms a symmetrical magnetic field distribution in the circumferential direction, resulting in a stable magnetic coupling effect of the phase coil in the core layer 4 direction.

[0037] In the above structure, the two semicircular coil segments of the three-phase coil generate magnetic fluxes in opposite directions. When three-phase alternating currents with a phase difference of 120° are applied to the three-phase coils, the bipolar magnetic fluxes generated in different layers of each phase coil are spatially superimposed to form a three-phase rotating magnetic field that rotates continuously with time. Since the three-phase magnetic fluxes rotate with equal amplitude in the time domain, the total amount of positive and negative magnetic fluxes at any given moment remains constant, making the overall magnetic field amplitude more stable, thereby enhancing the magnetic field strength and increasing the magnetic flux density and magnetic energy transfer density. The magnetic flux distribution in the circumferential direction of this rotating magnetic field is more balanced, effectively avoiding the problem of pulsating changes in magnetic flux over time in traditional single-phase structures, thus significantly improving the stability of magnetic coupling. Furthermore, under the action of the three-layer coil structure, the magnetic flux superposition effect in the longitudinal direction of the three-phase rotating magnetic field is more significant, making the longitudinal magnetic flux more concentrated and improving the energy coupling efficiency and power density between the transmitting and receiving coils.

[0038] Optionally, the average distance from each phase coil to the core layer 4 is equal, and the average distance is the weighted average of the distances from the coil portion of the coil segment in each layer of the three-layer stacked structure to the core layer 4.

[0039] In this embodiment, since each phase coil has coil portions located in different layers, each phase coil forms a different local distance distribution relative to the core layer 4. Based on this, by geometrically designing the positions of each phase coil in the coil stack structure, the average distance of the three phase coils relative to the core layer 4 can be made equal. The average distance is the weighted average of the distances from the coil portions of the corresponding phase coil located in each layer of the three-layer stack structure to the core layer 4. For example, different weights can be assigned to these distances based on the distance between the coil portions of the corresponding phase coil in each layer and the core layer 4 (the weights can be determined based on the proportion of each coil portion in the circumference or space of the corresponding phase coil) and weighted calculations can be performed to obtain the average distance of the phase coil as a whole. By making the average distance of the three phase coils to the core layer 4 equal, the three phase coils can form a consistent equivalent magnetic circuit length electromagnetically, thus making the self-inductance characteristics of the three phase coils basically consistent. Moreover, since the average distance of the three phase coils relative to the core layer 4 is equal, the coupling conditions between each phase coil in the core layer 4 are also consistent, making the equivalent mutual inductance characteristics between the three phases relatively balanced. Specifically, when the three-phase coils are in the same magnetic flux channel of the core layer 4, their magnetic flux coupling strength with the core layer 4 jointly determines the degree of coupling of the magnetic flux between phases. By keeping the average distance between the three-phase coils consistent, the magnetic flux generated by each phase can have a similar distribution range and penetration depth in the core layer 4, thereby achieving a relatively balanced state of equivalent mutual inductance between the three phases. This is beneficial for the three-phase electromagnetic coupling mechanism to form a stable three-phase current relationship and a symmetrical magnetic coupling path during operation.

[0040] Thus, the three-phase electromagnetic coupling mechanism of this embodiment, by setting A-phase coil 1, B-phase coil 2, and C-phase coil 3 with multi-layer distribution characteristics on the magnetic core layer 4, and ensuring that the average distance between the three-phase coils and the magnetic core layer 4 is equal, enables the three-phase coils to obtain a consistent equivalent magnetic circuit length on the electromagnetic coupling path. This effectively overcomes the problems of pulsating magnetic field distribution, limited magnetic flux coverage, and significant fluctuations in coupling capability with position in related technologies. Furthermore, compared to the defects in related technologies where the three-phase coil structure suffers from unbalanced self-inductance and asymmetrical inter-phase mutual inductance due to inconsistent distances between the coils and the magnetic core, leading to unbalanced three-phase current and magnetic field distribution, the three-phase electromagnetic coupling mechanism of this embodiment, through multi-layer arrangement and maintaining consistent average distances, ensures a high degree of consistency in the self-inductance and mutual inductance of the three-phase coils, enabling a more stable three-phase electromagnetic coupling relationship during wireless power transmission. Therefore, the three-phase electromagnetic coupling mechanism in this embodiment can effectively improve the coupling efficiency and transmission stability between the transmitting and receiving sides of wireless power transmission, providing a general and scalable three-phase electromagnetic coupling structure solution for building a high-efficiency and high-stability wireless power transmission system.

[0041] Optionally, the weight of the weighted average is determined based on the proportion of the coil portion of each phase coil located in the coil segment of each layer of the three-layer stacked structure on the 4-dimensional coverage of the core layer.

[0042] In this embodiment, to facilitate the quantitative analysis of the average distance from the three-phase coils to the core layer 4, the average distance is determined based on the distance between the two coil segments of each phase coil and the corresponding coil portion in each layer of the three-layer stacked structure, and the coverage ratio of each coil portion in the circumferential direction of the core layer 4. Specifically, the three-phase coils each include multiple coil portions distributed in different layers, with different vertical distances from each layer to the core layer 4, and different circumferential coverage of each coil portion in its layer. Therefore, the overall distance of the same phase coil relative to the core layer 4 can be obtained by weighting the distances of each coil segment to the coil portions in each layer of the three-layer stacked structure. In this calculation method, for a certain phase coil, there are certain proportions of coil portions in the first, second, and third layers, and each coil portion has a different vertical distance relative to the core layer 4. By using the coverage ratio of each coil portion in the circumferential direction of the core layer 4 as a weighting factor for its corresponding distance, the equivalent magnetic distance of the entire phase coil relative to the core layer 4 can be more accurately reflected.

[0043] Thus, the average distance obtained by the above method can truly reflect the distribution characteristics of the three-phase coils in the four directions of the core layer, so that the effective distance between the three-phase coils on the magnetic circuit remains consistent, providing a basic condition for the three-phase coils to form balanced self-inductance characteristics and stable interphase coupling relationship.

[0044] Optionally, to ensure that the average distance can effectively determine and reflect the true electromagnetic coupling relationship of each phase coil relative to the core layer 4, it is preferable that each phase coil adopts a relatively uniform circumferential coverage layout, so that the coil parts do not exhibit excessive concentration or excessive sparse distribution in the circumferential direction. By making the coil parts have a more balanced coverage ratio in the circumferential direction, the weight of each coil part in the average distance calculation can be more consistent with its contribution to the actual magnetic flux generated in the magnetic circuit, thereby enabling the final average distance to more accurately reflect the overall position of each phase coil in the stacked structure. In addition, the relative uniformity of circumferential coverage can also reduce the coupling deviation caused by excessively high local magnetic flux density to a certain extent, making the equivalent distance of the three-phase coils in the direction of the core layer 4 more consistent, providing a basic guarantee for the three-phase electromagnetic coupling mechanism to obtain balanced electromagnetic performance.

[0045] Optionally, referring to Figures 1-4, for one of the three phase coils 1, 2 phase B, and 3 phase C, two coil segments are distributed in the first and third layers of the three-layer stacked structure, respectively; for another coil segment, one-third of its coil portion is distributed in the first layer and two-thirds of its coil portion is distributed in the second layer of the three-layer stacked structure; for yet another coil segment, one-third of its coil portion is distributed in the third layer and two-thirds of its coil portion is distributed in the second layer; for yet another coil segment, one-third of its coil portion is distributed in the first layer, one-third of its coil portion is distributed in the second layer, and one-third of its coil portion is distributed in the third layer; for yet another coil segment, one-third of its coil portion is distributed in the first layer, one-third of its coil portion is distributed in the second layer, and one-third of its coil portion is distributed in the third layer.

[0046] In this embodiment, to ensure consistent coupling conditions between the phase coils in the core layer 4 and to achieve a relatively balanced equivalent mutual inductance among the three phases, the preferred distribution of the two semicircular coil segments of each phase coil in the three-layer stacked structure is as follows: One of the three phase coils (A-phase coil 1, B-phase coil 2, and C-phase coil 3) has two coil segments distributed in the first and third layers of the three-layer stacked structure, respectively; another of the three has one-third of its coil segment distributed in the first layer and two-thirds in the second layer; another of the three has one-third of its coil segment distributed in the third layer and two-thirds in the second layer; yet another of the three has one-third of its coil segment distributed in the first layer, one-third in the second layer, and one-third in the third layer; and yet another of the three has one-third of its coil segment distributed in the first layer, one-third in the second layer, and one-third in the third layer.

[0047] For example, the orthographic projection of each coil segment of phase A coil 1, phase B coil 2, and phase C coil 3 onto the core layer 4 is a semicircle covering a continuous 180° range in the circumferential direction of the core layer 4. To achieve the same average distance between the three-phase coils and the core layer 4, assuming equal interlayer distances in the three-layer stacked structure (e.g., equal intervals between the first, second, third, and core layers 4), the distribution of the two semicircular coil segments of each phase coil in the three-layer stacked structure can be designed as follows: the two semicircular coil segments of phase A are distributed in the first and third layers respectively; of the two semicircular coil segments of phase B, 1 / 3 of the positive polarity coil segment B+ is distributed in the first layer (i.e., the coil portion of B+ in the first layer corresponds to a central angle of 60°), and the other 2 / 3 of B+ is distributed in the second layer (i.e., the coil portion of B+ in the second layer corresponds to a central angle of 120°). One-third of the negative polarity coil segment B- is distributed in the third layer (i.e., the coil portion of B- in the third layer corresponds to a central angle of 60°), and the other two-thirds of B- is distributed in the second layer (i.e., the coil portion of B- in the second layer corresponds to a central angle of 120°). For the two semicircular coils of phase C, one-third of the positive polarity coil segment C+ is distributed in the first layer, the other one-third in the second layer, and the other one-third in the third layer; one-third of the negative polarity coil segment C- is distributed in the first layer, the other one-third in the second layer, and the other one-third in the third layer (i.e., the coil portions of C+ and C- in each layer correspond to a central angle of 60°), and the interlayer distribution of the positive and negative polarity coil segments is symmetrical.

[0048] Since the coverage ratio of each phase coil in different layers is clearly controllable, the average distance of the three-phase coils relative to the core layer 4 can be calculated using a weighted average method. Let the vertical distances from the first, second, and third layers to the core layer 4 be d1, d2, and d3, respectively, and the coverage weights of each phase coil in its corresponding layer be A-phase coil 1 (WA1, WA2, WA3), B-phase coil 2 (WB1, WB2, WB3), and C-phase coil 3 (WC1, WC2, WC3), respectively. Then, the average distance of each phase coil can be obtained (where the average distance from A-phase coil 1 to the core layer 4 is denoted as DA, and the average distance from B-phase coil 2 to the core layer 4 is denoted as DB). The average distance from phase C coil 3 to core layer 4 (denoted as DC) is as follows: DA = WA1*d1 + WA2*d2 + WA3*d3, DB = WB1*d1 + WB2*d2 + WB3*d3, DC = WC1*d1 + WC2*d2 + WC3*d3D. Substituting the corresponding coil weights of each phase in the above design, WA1 = WA3 = 180° / 360° = 1 / 2, WA2 = 0, WB1 = WB3 = 60° / 360° = 1 / 6, WB 2 = (120° + 120°) / 360° = 2 / 3, WC1 = WC2 = WC3 = 120° / 360° = 1 / 3; Given that the interlayer distances of the three-layer stacked structure are equal (d1 = 3d3, d2 = 2d3), then: DA = WA1 * d1 + WA2 * d2 + WA3 * d3 = 2d3, DB = WB1 * d1 + WB2 * d2 + WB3 * d3 = 2d3, DC = WC1 * d1 + WC2 * d2 + WC3 * d3 3D = 2d³. Therefore, under the above interlayer distribution, although the coverage of the three-phase coils varies in different layers, by precisely controlling the coverage ratio of each coil segment in each layer and the symmetrical distribution of the positive and negative polarities, the average distance between the three-phase coils and the core layer 4 can be made the same. This ensures that the three-phase coils have a consistent equivalent magnetic circuit length when coupled to the core layer 4, thus achieving consistent self-inductance, balanced interphase mutual inductance, and stable three-phase electromagnetic coupling characteristics in actual operation. Furthermore, based on the above interlayer distribution, the orthogonal projections of phase A coil 1, phase B coil 2, and phase C coil 3 on the core layer 4 are successively deflected by 120°, allowing the three-phase coils to be arranged closely together, further increasing space utilization. This also ensures that the magnetic circuit conditions of the three-phase coils when coupled to the core layer 4 are basically consistent, maintaining a balance in the self-inductance of the three-phase coils and contributing to the symmetry of the three-phase electromagnetic characteristics.

[0049] It is worth noting that the specific interlayer distribution ratio of phase A coil 1, phase B coil 2, and phase C coil 3 is an exemplary interlayer distribution method used to illustrate that by appropriately setting the circumferential coverage ratio of each coil segment in different layers, the average distance of each phase coil relative to the magnetic core layer 4 can reach the same value. This is not the only implementation of the present invention. As long as each phase coil is distributed in different layers of the coil stack structure according to a preset ratio, and the circumferential coverage ratio of each layer is weighted and calculated so that the average distance of the three phase coils is equal, the three-phase electromagnetic coupling consistency effect of the present invention can be achieved.

[0050] For example, each phase coil segment can be formed by continuously winding a single conductor (excitation wire) along a preset circumferential path. The conductor is unfolded in a multi-turn manner in the circumferential direction, so that the coil segment has a semi-circular shape when viewed from above. Since the distribution of each turn of the conductor in the circumferential direction of the coil segment is uniformly extended, and the spacing between each turn remains basically consistent, the coil segment forms a relatively uniform magnetic field contribution within the covered circumferential range. When the coil segment is arranged across layers, the coil parts in different layers can be bent to transition, still maintaining the overall uniformity of the coil segment in the circumferential direction, thereby ensuring that the coverage ratio of each coil part in the circumferential direction has good consistency. In this way, when calculating the weighted average distance, the weight of each layer of coil parts can be determined based on a clearly defined circumferential coverage ratio, so that the obtained average distance can accurately characterize the equivalent overall coupling position of the corresponding phase coil relative to the magnetic core layer 4, and the electromagnetic position of the phase coil in the three-layer stacked structure can be reasonably quantified.

[0051] Referring to Figure 5, another embodiment of the present invention provides a wireless power transmission system, including a wireless power transmitting mechanism 5 and a wireless power receiving mechanism 6, wherein at least one of the wireless power transmitting mechanism 5 and the wireless power receiving mechanism 6 includes the three-phase electromagnetic coupling mechanism described above.

[0052] In this embodiment, the wireless power transmission system includes a wireless power transmitting mechanism 5 and a wireless power receiving mechanism 6. At least one of the wireless power transmitting mechanism 5 and the wireless power receiving mechanism 6 adopts the aforementioned three-phase electromagnetic coupling mechanism as an electromagnetic energy conversion unit.

[0053] The wireless power transmitting mechanism 5 and the wireless power receiving mechanism 6 can both employ a three-phase electromagnetic coupling mechanism, or they can be employed only on the transmitting side or the receiving side. For example, when the wireless power transmitting mechanism 5 employs a three-phase electromagnetic coupling mechanism while the wireless power receiving mechanism 6 employs a conventional receiving coil, the wireless power transmission system can still improve the magnetic flux coverage and the system's anti-offset capability through the three-phase magnetic field formed on the transmitting side. Conversely, when the wireless power receiving mechanism 6 employs a three-phase electromagnetic coupling mechanism, it can also enhance the receiver's adaptability to different spatial magnetic field distributions and improve energy capture efficiency. If the wireless power transmitting mechanism 5 includes a drive circuit for generating AC excitation signals and a three-phase electromagnetic coupling mechanism electrically connected to the drive circuit, when the wireless power transmission system is working, the drive circuit provides three-phase AC signals to the A-phase coil 1, B-phase coil 2 and C-phase coil 3 of the three-phase electromagnetic coupling mechanism, so that it establishes a rotating or periodic magnetic field distribution around the magnetic core layer 4, and radiates electrical energy into space in a magnetic coupling manner; if the wireless power receiving mechanism 6 includes a three-phase electromagnetic coupling mechanism for receiving electromagnetic energy and a rectifier circuit or energy storage device electrically connected to it, when the wireless power transmission system is working, the three-phase electromagnetic coupling mechanism on the receiving side generates an induced voltage in response to the change of the magnetic field on the transmitting side, and provides electrical energy to the load 7 after rectification or conversion.

[0054] Thus, by employing a three-phase electromagnetic coupling mechanism in the wireless power transmitting mechanism 5 and / or the wireless power receiving mechanism 6, the wireless power transmission system can fully utilize the advantages of the three-phase electromagnetic structure in terms of magnetic field distribution continuity, coupling stability, and anti-offset performance, enabling the wireless power transmission system to maintain high coupling efficiency and strong transmission stability under conditions of different position offsets, attitude changes, or working distance changes.

[0055] Optionally, as shown in Figures 5 and 6, the wireless power transmitting mechanism 5 includes a first three-phase electromagnetic coupling mechanism 51, a primary-side resonant mechanism 52, a three-phase inverter 53, and a DC power supply 54, wherein the DC power supply 54, the three-phase inverter 53, the primary-side resonant mechanism 52, and the first three-phase electromagnetic coupling mechanism 51 are electrically connected in sequence.

[0056] In this embodiment, the wireless power transmitting mechanism 5 includes a first three-phase electromagnetic coupling mechanism 51. Based on this, the wireless power transmission system also includes a DC power supply 54, a three-phase inverter 53, and a primary-side resonant mechanism 52. The DC power supply 54, the three-phase inverter 53, the primary-side resonant mechanism 52, and the first three-phase electromagnetic coupling mechanism 51 are connected in sequence to convert the DC power output by the DC power supply 54 into a high-frequency AC magnetic field suitable for electromagnetic coupling transmission.

[0057] Specifically, the DC power supply 54 provides stable DC power for wireless power transmission and can be a battery pack, rectifier, or other DC power supply device. The three-phase inverter 53 (such as a three-phase high-frequency inverter) is electrically connected to the DC power supply 54. Its internal switching transistors, through high-speed turn-on and turn-off operations, can invert the DC voltage from the DC power supply 54 into a three-phase high-frequency AC signal. The frequency of this three-phase high-frequency signal can be set according to the operating requirements of the wireless power transmission system to match the resonant frequency of the primary-side resonant mechanism 52. The primary-side resonant mechanism 52 is electrically connected to the three-phase inverter 53, and its structure may include three-phase resonant capacitors, three-phase resonant inductors, or other electrical components capable of forming a resonant circuit. Through the resonance effect of the primary-side resonant mechanism 52, the three-phase high-frequency AC signal output by the three-phase inverter 53 can be adjusted to suitable voltage, current, or phase conditions, providing stable excitation for subsequent magnetic coupling. The first three-phase electromagnetic coupling mechanism 51 is electrically connected to the primary-side resonant mechanism 52 and is used to establish a corresponding high-frequency magnetic field around the magnetic core layer 4 according to the three-phase high-frequency AC signal output by the primary-side resonant mechanism 52. When the wireless power transmission system is in operation, the first three-phase electromagnetic coupling mechanism 51 forms a periodic or rotating magnetic field distribution in space, so that magnetic energy is transmitted to the receiving side through spatial coupling, thereby realizing non-contact transmission of wireless power.

[0058] Thus, through the aforementioned electrical connections, the wireless power transmission system can realize a complete energy conversion link from DC input to high-frequency magnetic field excitation, enabling the wireless power transmitting mechanism 5 to establish the required electromagnetic energy transmission environment under conditions of high efficiency and high stability, and providing a stable magnetic coupling input for the wireless power receiving mechanism 6.

[0059] For example, the three-phase inverter 53 includes six (or 6n, where n is a positive integer) power switching devices, such as MOSFETs, IGBTs, or other power semiconductor devices suitable for high-frequency operation. The three-phase inverter 53 controls the switching sequence of each power switching device in a preset manner, causing the output of the DC power supply 54 to be inverted into a high-frequency three-phase alternating current (e.g., 85kHz) to drive the energy exchange process of the primary-side resonant mechanism 52 and excite the first three-phase electromagnetic coupling mechanism 51 to operate.

[0060] Optionally, as shown in Figures 5 and 6, the wireless power transmitting mechanism 5 includes a second three-phase electromagnetic coupling mechanism 61, a secondary resonant mechanism 62, and a three-phase rectifier 63, which are electrically connected in sequence.

[0061] In this embodiment, the wireless power transmitting mechanism 5 includes a second three-phase electromagnetic coupling mechanism 61. Based on this, the wireless power transmission system also includes a secondary resonant mechanism 62 and a three-phase rectifier 63. The second three-phase electromagnetic coupling mechanism 61, the secondary resonant mechanism 62 and the three-phase rectifier 63 are electrically connected in sequence to convert the AC signal obtained by electromagnetic coupling on the receiving side into DC power that can be used by the corresponding load 7.

[0062] Specifically, the second three-phase electromagnetic coupling mechanism 61 is used to induce a three-phase AC signal under the magnetic field established by the wireless power transmitting mechanism 5. When the wireless power transmission system is working, the magnetic field generated on the transmitting side passes through the air gap to the receiving side. The second three-phase electromagnetic coupling mechanism 61 induces a voltage in its three-phase coils according to the change of the spatial magnetic field, thereby obtaining AC input. The secondary resonant mechanism 62 is electrically connected to the second three-phase electromagnetic coupling mechanism 61. Its structure may include a three-phase resonant capacitor, a three-phase resonant inductor, or other electrical components that can form a resonant network. This resonant mechanism is used to adjust the three-phase AC signal induced on the receiving side to the target frequency or amplitude range, so as to improve the utilization rate of magnetic field energy on the receiving side, reduce resonance loss, and improve the overall energy transfer efficiency. The three-phase signal output from the secondary resonant mechanism 62 is further input to the three-phase rectifier 63. The three-phase rectifier 63 can be a three-phase diode bridge, a three-phase synchronous rectifier module, or other rectifier circuits suitable for three-phase AC power conversion. This rectifier is responsible for rectifying the high-frequency three-phase AC signal output from the secondary resonant mechanism 62 into DC power, and can be connected to the downstream filter, energy storage device, or load 7 power supply circuit at its output terminal to achieve stable power supply to the load 7.

[0063] Thus, through the aforementioned electrical connection, the receiving side of the wireless power transmission system can convert the energy transmitted by magnetic coupling into directly usable DC power, providing a complete receiving link for the wireless power transmission system; and the receiving side has functions such as resonant matching and rectification conversion, which can improve the energy receiving efficiency and transmission stability during the overall operation of the wireless power transmission system.

[0064] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A three-phase electromagnetic coupling mechanism, characterized in that, The structure includes a magnetic core layer (4) and an A-phase coil, a B-phase coil, and a C-phase coil stacked on the magnetic core layer (4). The A-phase coil, the B-phase coil, and the C-phase coil form a three-layer stacked structure. The A-phase coil, the B-phase coil, and the C-phase coil each include two electrically connected coil segments. Each coil segment covers a 180° corresponding area along the circumference of the magnetic core layer (4). The two coil segments of each phase coil have centrally symmetrical orthographic projections on the magnetic core layer (4). Each layer of the three-layer stacked structure has coil portions of at least two coil segments of different phase coils.

2. The three-phase electromagnetic coupling mechanism as described in claim 1, characterized in that, The A-phase coil, the B-phase coil, and the C-phase coil have the same orthographic projection shape on the magnetic core layer (4), and are deflected by 120° in sequence.

3. The three-phase electromagnetic coupling mechanism as described in claim 1, characterized in that, Each of the coil segments has a semi-circular orthographic projection on the magnetic core layer (4), and each of the coil portions has a fan shape.

4. The three-phase electromagnetic coupling mechanism as described in any one of claims 1-3, characterized in that, The same coil segment is bent and transitioned between the coil portions of different layers in the three-layer stacked structure.

5. The three-phase electromagnetic coupling mechanism as described in any one of claims 1-3, characterized in that, The average distance from each phase coil to the magnetic core layer (4) is equal, and the average distance is the weighted average of the distances from the coil portion of the coil segment of the corresponding phase coil located in each layer of the three-layer stacked structure to the magnetic core layer (4).

6. The three-phase electromagnetic coupling mechanism as described in claim 5, characterized in that, The weight of the weighted average is determined based on the proportion of the coil portion of the coil segment in each layer of the three-layer stacked structure on the circumferential coverage of the magnetic core layer (4).

7. The three-phase electromagnetic coupling mechanism as described in claim 5, characterized in that, Of the three phases of coil A, coil B, and coil C, two coil segments of one are respectively distributed in the first and third layers of the three-layer stacked structure; one-third of the coil portion of one coil segment of another is distributed in the first layer, two-thirds of the coil portion is distributed in the second layer of the three-layer stacked structure, and one-third of the coil portion of the other coil segment of the other is distributed in the third layer, and two-thirds of the coil portion is distributed in the second layer; one-third of the coil portion of one coil segment of yet another is distributed in the first layer, one-third of the coil portion is distributed in the second layer, and one-third of the coil portion is distributed in the third layer, and one-third of the coil portion of the other coil segment of yet another is distributed in the first layer, one-third of the coil portion is distributed in the second layer, and one-third of the coil portion is distributed in the third layer.

8. A wireless power transmission system, characterized in that, It includes a wireless power transmitting mechanism (5) and a wireless power receiving mechanism (6), at least one of the wireless power transmitting mechanism (5) and the wireless power receiving mechanism (6) including a three-phase electromagnetic coupling mechanism as described in any one of claims 1-7.

9. The wireless power transmission system as described in claim 8, characterized in that, The wireless power transmitting mechanism (5) includes a first three-phase electromagnetic coupling mechanism (51), a primary-side resonant mechanism (52), a three-phase inverter (53), and a DC power supply (54), wherein the DC power supply (54), the three-phase inverter (53), the primary-side resonant mechanism (52), and the first three-phase electromagnetic coupling mechanism (51) are electrically connected in sequence.

10. The wireless power transmission system as described in claim 8, characterized in that, The wireless power transmitting mechanism (5) includes a second three-phase electromagnetic coupling mechanism (61), a secondary resonant mechanism (62), and a three-phase rectifier (63), which are electrically connected in sequence.

Images