A reverse parallel cross resonator applied to implantable wireless power transmission and an optimization design method

Abstract

This application provides a reverse-parallel cross-resonator and its optimized design method for implantable wireless power transmission, solving the technical problems of unstable energy transmission due to the human tissue environment, difficulty in balancing miniaturization and high power density, excessive electrical stress on devices caused by resonant tuning methods, and difficulty in selecting compensation capacitors for high-frequency operation in existing implantable wireless power supply systems. It includes a transmitter and a receiver, both of which are reverse-parallel cross-resonant structures. The reverse-parallel cross-resonant structure is a multi-layer spiral coil, with each layer of coil interconnected to form a parallel equivalent circuit. The inter-turn parasitic capacitance, inter-layer parasitic capacitance, and equivalent inductance of the coils constitute a self-resonant network, achieving the target resonant frequency in a predetermined megahertz band. This application can be widely applied in the field of wireless charging technology.

Description

Technical Field

[0001] This application belongs to the field of wireless charging technology, and more specifically, relates to an anti-parallel cross resonator and its optimization design method for implantable wireless power transmission. Background Technology

[0002] Real-time monitoring and remote transmission of vital signs have clinical application value in the diagnosis, treatment, and functional regulation of internal organs. Currently, some implantable medical devices rely on disposable batteries for power, requiring surgical replacement after the battery is depleted. This carries risks such as wound infection, tissue scarring, and anesthesia-related complications, increasing the burden on patients.

[0003] With the development of wireless power transfer and low-power integrated circuit technologies, implantable medical devices can obtain the energy required for long-term operation through percutaneous wireless power supply, thereby reducing medical risks and improving patient experience. However, achieving stable wireless power supply in the complex and non-uniform human tissue environment still faces multiple challenges. On the one hand, different implantation sites (e.g., intracranial, intramyocardial, subcutaneous, or gastrointestinal) and different implantation depths will change the energy transmission path and electromagnetic field distribution, making the coupling coefficient between coils susceptible to fluctuations due to factors such as tissue dielectric constant, conductivity, and positional offset. On the other hand, due to limitations such as battery and coil volume and weight, some systems struggle to achieve high power density while meeting the requirements of comfortable implantation and biocompatibility. Furthermore, the system is quite sensitive to the relative position and angle between the implanted end and the external power supply coil; when offset occurs, transmission efficiency may decrease, or even insufficient power supply may occur.

[0004] Against this backdrop, implantable devices are evolving towards higher integration, miniaturization, and lighter weight, which places higher demands on the design of magnetically coupled coils, compensation networks, and overall electromagnetic compatibility. Currently, magnetically coupled wireless power supply systems mostly employ centralized capacitor series / parallel connections to achieve resonant tuning. However, devices are susceptible to significant electrical stress under resonant conditions, limiting their reliability. For example, in series compensation, the voltage across the compensation capacitor amplifies with the quality factor Q of the resonant circuit; in parallel compensation, the increased circulating current in the branch leads to increased current stress in the compensation capacitor, resulting in parameter drift, device failure, and resonant point shift. Especially in biomedical implants and wearable applications, due to coil size limitations, self-inductance is typically low, and systems often need to achieve resonance in the MHz frequency band; simultaneously, to meet spectrum usage compliance requirements, system operating frequencies are often set in the Industrial, Scientific and Medical (ISM) bands such as 6.78 MHz, 13.56 MHz, 27.12 MHz, and 40.68 MHz. The above factors further increase the difficulty of selecting compensation capacitors in terms of withstand voltage, high-frequency voltage / current stress, device size and cost, which is not conducive to the miniaturization, high integration and long-term stable operation of implantable devices. Summary of the Invention

[0005] The purpose of this application is to provide an anti-parallel cross resonator for implantable wireless power transmission systems, in order to solve the technical problems in the prior art, such as unstable energy transmission due to the human tissue environment, difficulty in balancing miniaturization and high power density, excessive electrical stress on devices caused by resonant tuning methods, and difficulty in selecting compensation capacitors under high-frequency operation.

[0006] To achieve the above objectives, the first embodiment of this application provides an anti-parallel cross resonator for implantable wireless power transmission, comprising: a transmitter and a receiver, both of which are anti-parallel cross resonant structures; The reverse cross-parallel resonant structure is a multi-layer spiral coil, with each layer of coil interconnected to form a parallel equivalent circuit. The inter-turn parasitic capacitance, inter-layer parasitic capacitance, and equivalent inductance of the coil are used to form a self-resonant network, achieving the target resonant frequency in the predetermined megahertz frequency band.

[0007] Preferably, in a multi-layer spiral coil, the coils of adjacent layers are wound in opposite directions.

[0008] Preferably, in a multilayer spiral coil, the coils of each layer are electrically connected across layers through through holes to form parallel ports.

[0009] Preferably, the reverse cross-parallel resonant structure is a PCB-based multilayer spiral coil, in which each coil and dielectric layer are alternately stacked.

[0010] Preferably, the two ends of the reverse cross-parallel resonant structure are open circuit terminals.

[0011] Preferably, the dielectric layer uses an FR-4 dielectric substrate.

[0012] Preferably, the anti-parallel cross resonator is encapsulated with medical-grade silicone rubber and Parylene C material.

[0013] The second embodiment of this application provides an optimized design method for an anti-parallel cross resonator applied to implantable wireless power transfer, including: Based on the structural space, packaging form and processing technology limitations of implantable devices, the structural parameters of the anti-parallel cross resonator are determined, and the initial electromagnetic simulation models of the transmitter and receiver are established. Based on the scenarios and standards of implantable devices, the target resonant frequency is determined, and the transmitter and receiver are constrained to achieve resonance matching at the target resonant frequency. By fixing the number of layers and thickness of the anti-parallel cross resonator, the equivalent inductance and parasitic capacitance are changed by adjusting the geometric parameters of the multi-layer spiral coils in the anti-parallel cross resonator, so that the self-resonant frequency approaches the target resonant frequency. The parameter search of the transmitter and receiver is completed by parameter scanning to obtain the parameter combination. Select parameter combinations that meet the target resonant frequency and verify whether they meet the consistency requirements. If so, obtain the final physical parameters of the anti-parallel cross resonator; otherwise, readjust the geometric parameters of the multilayer spiral coil together with parameter combinations that do not meet the target resonant frequency.

[0014] Preferably, the anti-parallel cross resonator is divided into multiple micro-segments along the current path according to the electrical length, and a distributed parameter model is established based on the electrical parameters per unit length and the micro-segment length. The equivalent impedance of each micro-segment is obtained by solving the voltage and current relationships of each micro-segment. The total equivalent impedance of the anti-parallel cross resonator is obtained by cascading the equivalent impedances of each micro-segment, which characterizes the electromagnetic field distribution and frequency response of the anti-parallel cross resonator and is used to design the geometric parameters of the multilayer spiral coil.

[0015] Preferably, the thickness of the dielectric layer, dielectric parameters, and conductor thickness are set, and the geometric parameters of each coil in the multilayer spiral coil are combined to achieve the adjustment of the self-resonant frequency.

[0016] The beneficial effects of this application are as follows: This application provides a reverse-parallel cross-resonator and its optimized design method for implantable wireless power transmission. By adopting a unified reverse-parallel cross-resonant structure for both the transmitter and receiver, the perturbation of the coupling coefficient and resonant point by the dielectric constant, conductivity, and positional offset of human tissue is significantly reduced. This maintains stable transmission efficiency and resonant state even under tissue environment fluctuations, achieving stable power supply. Specifically, the reverse-parallel cross-resonant structure employs multi-layer spiral coils, which, through cross-interconnection, form a parallel equivalent circuit. This not only increases the equivalent coupling area and magnetic field strength within a limited implantation volume, achieving compatibility between miniaturized packaging and high power density, meeting the size constraints of implantable devices, but also effectively suppresses the electric field concentration effect under high-frequency operation by optimizing coil geometry and electric field distribution, reducing device electrical stress, avoiding the risk of dielectric breakdown and insulation failure, and improving the long-term safety of the resonator. Furthermore, this application relies on the parasitic capacitance of the coil itself to construct a self-resonant circuit, eliminating the need for external centralized compensation capacitors, weakening the impact of biological tissue environment fluctuations on the resonant point, and improving the stability and reliability of the resonance. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A front view of an anti-parallel cross resonator provided in an embodiment of this application; Figure 2 A side view of an anti-parallel cross resonator provided in an embodiment of this application; Figure 3 An equivalent circuit diagram of a segmented anti-parallel cross resonator provided in an embodiment of this application; Figure 4 A cross-sectional view of an anti-parallel cross resonator provided in an embodiment of this application; Figure 5 A flowchart illustrating the optimized design of a reverse parallel cross resonator according to an embodiment of this application. Detailed Implementation

[0019] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0020] This application provides an anti-parallel cross resonator for implantable wireless power transmission and its optimized design method. The anti-parallel cross resonator employs a consistent anti-parallel cross resonant structure at both the transmitting and receiving ends. Systematic optimization has been performed in the topology and electromagnetic parameter design, taking into account miniaturization, stability, and biocompatibility. It can maintain stable resonance performance and energy transmission efficiency even under conditions of tissue medium parameter fluctuations and device installation deviations.

[0021] Please see Figure 1 The first embodiment of this application provides an anti-parallel cross-resonator for implantable wireless power transmission, comprising a transmitter and a receiver, both of which are anti-parallel cross-resonant structures. This makes the structures of the transmitter and receiver uniform and compact, facilitating parameter co-design and meeting the size constraints of the implant.

[0022] Specifically, the reverse cross-parallel resonant structure is a multi-layered spiral coil, with each layer of coil interconnected to form a parallel equivalent circuit. The inter-turn parasitic capacitance, inter-layer parasitic capacitance, and equivalent inductance of the coils constitute a self-resonant network, achieving the target resonant frequency in a predetermined megahertz band. This application relies on the inherent parasitic capacitance of the coils to construct the self-resonant circuit, eliminating the need for external centralized compensation capacitors, reducing the impact of fluctuations in the biological tissue environment on the resonant point, and improving the stability and reliability of the resonance.

[0023] Furthermore, the reverse cross-parallel resonant structure is based on a multilayer spiral coil on a printed circuit board (PCB), with the multilayer spiral coil and dielectric layer stacked alternately. This architecture can not only rely on mature processes to precisely control parasitic parameters and ensure resonant stability, but also achieve miniaturized and insulated integration, facilitating mass production modeling.

[0024] Preferably, in the multilayer helical coil, the coils of adjacent layers are wound in opposite directions. In an optional embodiment, both the transmitting and receiving ends employ the same reverse parallel cross-four-layer helical coil structure, differing only in the specific geometric parameters of the coils. The overall structure consists of coil layers and dielectric layers from top to bottom. Figure 1 The layers are composed of alternating medium gray layers. Specifically, the first and third layers of coils (…) Figure 1 The middle blue layer is wound in the same direction (e.g., counterclockwise from the inside to the outside), and the second and fourth layers of coils ( Figure 1 The middle yellow layer is wound in the opposite direction to the first layer (e.g., clockwise from the outside to the inside). By winding adjacent coils in the opposite direction and arranging them in a spatial stack, the equivalent coupling area can be increased within a limited thickness, the longitudinal magnetic field component can be enhanced, and some leakage magnetic field and far-field radiation can be suppressed. This is beneficial for improving the system coupling coefficient and reducing electromagnetic interference to surrounding tissues.

[0025] Furthermore, in the multilayer spiral coil, the coils of each layer are electrically connected across layers through through-holes to form parallel ports. Specifically, in an optional embodiment, in the four-layer spiral coil, two electrical connection output ports are provided on the first layer, denoted as output terminal A and output terminal B, respectively. Output terminal A is electrically connected to the first and third layer coils through through-holes and then led out on the top layer as a solder pad; output terminal B is electrically connected to the second and fourth layer coils through through-holes and then led out on the top layer as a solder pad.

[0026] Please see Figure 2 , Figure 2 This is a side view of an anti-parallel cross resonator provided in one embodiment of this application. In some embodiments, the anti-parallel cross resonator structure employs an open-circuit terminal structure at both ends to form a voltage / current distribution characteristic inside the anti-parallel cross resonator, thereby providing a design margin for impedance matching of the subsequent rectifier circuit and allowing adjustment of the output voltage and efficiency according to load requirements.

[0027] In a preferred embodiment, to reduce the adverse effects that may be caused by changes in mechanical stress in the implantation environment, the overall planar shape of the anti-parallel cross resonator is preferably circular. The shape of the anti-parallel cross resonator is not limited here and can be set according to the shape of the implantation cavity.

[0028] In some embodiments, the conductor material of each layer of the multilayer spiral coil is copper, and copper foil with a thickness of 17.5–35 μm can be used; the dielectric layer preferably uses FR-4 dielectric substrate, whose relative permittivity is preferably 4.0–4.8, and whose loss tangent is preferably less than 0.02. The dielectric loading effect of the FR-4 dielectric substrate is used to adjust the matching relationship between parasitic capacitance and equivalent inductance, so that the resonant frequency is mainly determined by distributed parameters, thereby reducing the dependence on centralized compensation capacitors and reducing frequency mismatch caused by tolerance and temperature changes of discrete components.

[0029] Furthermore, the anti-parallel cross resonator can be encapsulated with medical-grade silicone rubber, Parylene C, or other biocompatible materials to isolate the metal conductor from surrounding tissue.

[0030] The second embodiment of this application provides an optimized design method for an anti-parallel cross resonator applied to implantable wireless power transfer, including: Based on the above structure and material configuration, the equivalent inductance and equivalent capacitance of the anti-parallel cross resonator exist as distributed parameters: the coil conductors form the equivalent inductance, and the inter-turn capacitance and inter-layer capacitance together form the equivalent parasitic capacitance. When using FR-4 as the dielectric substrate, its relative permittivity is higher than that of air, which can be used to increase the inter-layer parasitic capacitance, enabling the resonator to achieve self-resonance without the need for additional series or parallel centralized compensation capacitors.

[0031] Furthermore, by selecting the thickness, dielectric parameters, and conductor thickness of the FR-4 dielectric substrate in the dielectric layer, and combining it with the geometric parameters such as the line width, line spacing, number of turns, and inner and outer diameters of the coil, the self-resonant frequency (SRF) can be adjusted within a certain range, thereby adapting to implantable medical devices (such as pacemakers, nerve stimulators, drug infusion pumps, etc.) operating in different frequency bands.

[0032] In some embodiments, since the target resonant frequency of the anti-parallel cross resonator is on the order of MHz, and the electrical length of the coil layer reaches a non-negligible level due to the influence of dielectric loading and multilayer wiring, it can be modeled and analyzed as a distributed parameter structure. This application divides the resonator along the current path into multiple micro-segments according to electrical length, and uses the electrical parameters per unit length (… , , ) × Micro-segment length ( A distributed parameter model is established by solving for the voltage of each micro-segment. and Current and The relationship yields the equivalent impedance of the microsegment. The equivalent impedances of each micro-segment are cascaded to obtain the total equivalent impedance of the resonator. This modeling method can be used to characterize the electromagnetic field distribution and frequency response of the resonator, and to guide the design of parameters such as coil size, layer spacing, and number of turns.

[0033] Specifically, in one alternative embodiment, please refer to Figure 3 The diagram shows four parallel branches from top to bottom, corresponding to the first, second, third, and fourth layers of coils in a four-layer anti-parallel cross-resonator. Each of the four coil layers has a series resistor branch, and the layers are connected by distributed capacitance. or conductivity Coupling, and there is also mutual inductance coupling between layers. The bottom satisfies Kirchhoff's Current Law (KCL) and the overall current relationship is satisfied. Cascaded. Each branch of the four-layer coil contains... ,in, This indicates that the coil in this layer is within a micro-segment length. The resistance of the conductor inside. Each branch has a voltage across its left and right ends. and Current and , indicating the length of the micro-segment Internally, the electrical parameters of the transmitting and receiving ends.

[0034] Furthermore, the first and second layers are connected by interlayer parasitic capacitance. equivalent conductivity of the medium The second and third layers are connected via interlayer parasitic capacitance. equivalent conductivity of the medium The third and fourth layers are connected via interlayer parasitic capacitance. equivalent conductivity of the medium The first and fourth layers are connected via interlayer parasitic capacitance. equivalent conductivity of the medium Connections. In the diagram, , , , , , These represent the mutual inductive coupling between different layers of coils. Four current sources are connected at the bottom of the diagram, labeled as follows: This indicates that the current in the four-layer coil satisfies Kirchhoff's Current Law (KCL) within the micro-segment, meaning the algebraic sum of the total current is zero, indicating that the current in the multilayer structure is continuous.

[0035] Please see Figure 4 This is a schematic diagram of the cross-sectional structure of a resonator provided in an embodiment of this application. Figure 4 As shown, the resonator is composed of alternating layers of coil conductors and dielectric layers. The coil conductor layers have electrical conductivity. With permeability The conductor thickness is denoted as The conductor line width is denoted as The conductor winding length (i.e., the total length of the coil trace) is denoted as... The dielectric layer has a relative permittivity. Loss tangent and permeability The thickness of the dielectric layer is denoted as .

[0036] In some embodiments, the number of layers of the receiver resonator and the thickness of the dielectric layer Conductor thickness and material parameters (relative permittivity) Loss tangent The design of the receiving end resonator is determined during the structural design and process selection phase, and is not easily adjusted later due to limitations in implantation space and packaging technology. In contrast, the transmitting end resonator has greater design freedom in terms of volume, shape, and matching method, and can be adjusted through external dimensions and matching networks. Therefore, in some implementations, the optimization focus can be placed on the receiving end resonator, which has more stringent constraints, and under given layer number and thickness conditions, optimization can be mainly achieved by adjusting coil geometric parameters (number of turns, line width). Performance optimization of the transmitter and receiver is achieved through parameters such as line spacing, inner diameter, and outer diameter.

[0037] Specifically, the equivalent inductance, distributed capacitance, and quality factor of the resonator can be adjusted by changing parameters such as the number of coil turns, line width, line spacing, inner diameter, and outer diameter. For the receiver, energy transmission efficiency and resonance stability can be improved while meeting the limitations of implantation size and specific absorption rate (SAR). For the transmitter, coupling capability and energy transfer efficiency can be improved while meeting the requirements of size and system matching.

[0038] Based on the above considerations, the optimization design process for the transmitter and receiver resonators may include the following steps: Please see Figure 5 Based on the structural space, packaging form and processing technology limitations of implantable medical devices, the structural parameters of the resonator are determined, including coil geometric parameters, conductor layer thickness, dielectric layer thickness and coil outer diameter, etc., and initial electromagnetic simulation models of the transmitter and receiver are established. For the receiver, constraints such as implantation depth, available cavity size and encapsulation thickness can also be considered.

[0039] The target resonant frequency is preset, and then determined in conjunction with the target application scenario and relevant standard requirements. This is used as a constraint for geometric parameter optimization; the resonators at the transmitter and receiver resonators are at the target resonant frequency. Resonant matching is achieved in the vicinity.

[0040] Self-resonant tuning, under the condition of fixed number of layers and thickness, changes the equivalent inductance and parasitic capacitance by adjusting geometric parameters such as the number of turns, line width, line spacing, and inner diameter, so that the self-resonant frequency (SRF) approaches the target resonant frequency. Parameters can be searched on both the transmitting and receiving sides using parameter scanning or optimization algorithms. The formula is as follows: ; In the formula, It is the self-resonant frequency. The target resonant frequency, This is the relative error threshold for the resonant frequency.

[0041] A comprehensive multi-indicator screening process is employed. Among parameter combinations that meet the target resonant frequency condition, the quality factor, coupling coefficient, voltage standing wave ratio (VSWR), and SAR (specific absorptivity) under an equivalent human tissue model are evaluated. Parameter combinations that do not meet the target resonant frequency condition will undergo re-resonant frequency tuning (adjusting the geometric parameters of the multilayer spiral coils in the anti-parallel cross resonator). At the receiver end, the efficiency stability and SAR margin under different implantation postures, positional offsets, and tissue parameter variations can be specifically evaluated.

[0042] Multiple experiments were conducted for verification and finalization. Samples were prepared based on the selected parameter combinations, and indicators such as coil parameters, transmission efficiency, VSWR, temperature rise, and SAR were tested to verify whether the simulation and experiment were consistent and met the performance and safety requirements. Based on this, the final physical parameters of the transmitter and receiver resonators, including geometric dimensions and parameter configurations, were determined. The comparison of various indicators under simulation and experiment is shown in Table 1, where the transmission distance d between the transmitter and receiver is 15 mm.

[0043] Table 1 Comparison of various performance indicators in resonator optimization simulation and experiment.

[0044]

[0045] The table shows that the key indicators of the simulation and experiment are highly consistent with each other, with minimal deviation and good consistency, indicating the accuracy of the simulation model and the feasibility of the scheme. All indicators meet the performance and safety requirements. The final optimized physical parameters of the launch side are determined as follows: number of turns n=7, line width w=1.889mm, line spacing s=0.15mm, inner diameter d... in =26.749mm, t=0.035mm; the optimized physical parameters of the receiver side are determined as follows: number of turns n=22, line width w=0.205mm, line spacing s=0.195mm, inner diameter d in =2.325mm; the copper thicknesses of each layer are t1=0.035mm, t2=0.0175mm, t3=0.0175mm, and t4=0.035mm respectively; the thicknesses of each dielectric layer are h1=0.092mm, h2=0.700mm, and h3=0.092mm respectively.

[0046] After completing the above optimization process and determining the final physical parameters of the transmitter and receiver resonators, device fabrication and system integration can be carried out accordingly, so that the receiver is in a self-resonant state and matches the transmitter side in practical applications, in order to meet the size, performance and safety requirements of implantable applications.

[0047] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0048] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A reverse parallel cross resonator applied to implantable wireless power transmission, comprising a transmitting end and a receiving end, characterized in that, Both the transmitting end and the receiving end are reverse cross-parallel resonant structures; The reverse cross-parallel resonant structure is a multi-layer spiral coil, with each layer of coil interconnected to form a parallel equivalent circuit. The inter-turn parasitic capacitance, inter-layer parasitic capacitance, and equivalent inductance of the coil are used to form a self-resonant network, achieving the target resonant frequency in the predetermined megahertz frequency band.

2. The anti-parallel cross resonator for implantable wireless power transmission as described in claim 1, characterized in that, In the multi-layered spiral coil, the coils in adjacent layers are wound in opposite directions.

3. The anti-parallel cross resonator for implantable wireless power transmission as described in claim 1, characterized in that, In the multi-layer spiral coil, the coils in each layer are electrically connected across layers through through holes to form parallel ports.

4. The anti-parallel cross resonator for implantable wireless power transmission as described in claim 1, characterized in that, The reverse cross-parallel resonant structure is a PCB-based multilayer spiral coil in which each coil and dielectric layer are alternately stacked.

5. The anti-parallel cross resonator for implantable wireless power transmission as described in claim 1, characterized in that, The two ends of the reverse cross-parallel resonant structure are open circuit terminals.

6. The anti-parallel cross resonator for implantable wireless power transmission as described in claim 4, characterized in that, The dielectric layer uses an FR-4 dielectric substrate.

7. The anti-parallel cross resonator for implantable wireless power transmission as described in claim 1, characterized in that, The reverse parallel cross resonator is encapsulated with medical-grade silicone rubber and Parylene C material.

8. The optimization design method of the reverse parallel cross resonator applied to the implantable wireless power transmission, applied to the reverse parallel cross resonator applied to the implantable wireless power transmission in any one of claims 1-7, characterized in that, include: Based on the structural space, packaging form and processing technology limitations of implantable devices, the structural parameters of the anti-parallel cross resonator are determined, and the initial electromagnetic simulation models of the transmitter and receiver are established. Based on the scenario and standards of the implantable device, a target resonant frequency is determined, and the transmitting end and the receiving end are constrained to achieve resonance matching at the target resonant frequency. By fixing the number of layers and thickness of the anti-parallel cross resonator, the equivalent inductance and parasitic capacitance are changed by adjusting the geometric parameters of the multilayer spiral coils in the anti-parallel cross resonator, so that the self-resonant frequency approaches the target resonant frequency. The parameter search of the transmitter and receiver is completed by parameter scanning to obtain the parameter combination. Select parameter combinations that satisfy the target resonant frequency and verify whether they meet the consistency requirements. If so, obtain the final physical parameters of the anti-parallel cross resonator; otherwise, readjust the geometric parameters of the multilayer spiral coil together with parameter combinations that do not satisfy the target resonant frequency.

9. The optimized design method for an anti-parallel cross resonator applied to implantable wireless power transmission as described in claim 8, characterized in that, The reverse parallel cross resonator is divided into multiple micro segments along the current path according to the electrical length, and a distributed parameter model is established based on the unit length electrical parameter and the micro segment length. The equivalent impedance of each micro segment is obtained by solving the voltage and current sum relationship, and the total equivalent impedance of the reverse parallel cross resonator is obtained by cascading the equivalent impedance of each micro segment, which characterizes the electromagnetic field distribution and frequency response of the reverse parallel cross resonator, and is used for designing the geometric parameters of the multi-layer spiral coil.

10. The optimization design method of the reverse parallel cross resonator applied to the implantable wireless power transmission according to claim 9, wherein the thickness of the medium layer, the dielectric parameters and the conductor thickness are set to cooperate with the geometric parameters of each coil in the multi-layer spiral coil to adjust the self-resonant frequency. ​

Images