An underwater wireless power transmission system parameter optimization method based on high-precision eddy current loss modeling

Abstract

The application discloses a kind of underwater wireless power transmission system parameter optimization methods based on high-precision eddy current loss modeling, and it relates to wireless power transmission technical field.The application establishes the full-dimensional eddy current loss analytical electromagnetic field model, can quantify the self-eddy current loss of transmitting and receiving coils, while deducing the calculation method of mutual eddy current loss, solve the problem of big error in eddy current loss calculation under high-frequency working condition in the prior art, provide high-precision loss model support for system design.

Description

Technical Field

[0001] This invention discloses a parameter optimization method for an underwater wireless power transfer system based on high-precision eddy current loss modeling, which relates to the field of wireless power transfer technology. Background Technology

[0002] With the rapid development of marine resource development and underwater exploration technology, the application scale of marine equipment such as autonomous underwater vehicles and electric ships continues to expand, and their energy replenishment and charging needs are becoming increasingly prominent. Existing underwater equipment mainly uses direct contact charging systems. While this method can achieve high power transmission efficiency, it suffers from many drawbacks in humid, high-salt underwater environments, including contact corrosion, biofouling, complex plugging and unplugging operations, and safety accidents caused by insulation failure. Therefore, it cannot meet the long-term, safe, and reliable charging needs of underwater equipment.

[0003] Wireless power transfer technology, with its advantages of being contactless, plug-free, and electrically isolated, has become an ideal solution for charging underwater equipment, effectively addressing the safety and reliability concerns of direct contact charging. However, seawater, as a conductive medium, induces eddy currents when high-frequency alternating electromagnetic fields propagate through it, generating significant eddy current losses. These losses directly lead to a decrease in system transmission efficiency and a reduction in output power, representing a core bottleneck restricting the performance improvement of underwater wireless power transfer systems. In existing technologies, system designs often suffer from the following defects: First, most design schemes ignore the impact of seawater eddy current losses or only make simplified estimates of eddy current losses without establishing accurate analytical models. This makes it impossible to quantify the correlation between eddy current losses and coil design parameters and operating frequency, resulting in significant deviations between the system's performance and design expectations in actual underwater environments. Second, traditional equivalent circuit modeling does not fully integrate eddy current losses into circuit parameters, especially ignoring the mutual eddy current losses generated by the coupling between the transmitting and receiving coils, making it impossible to accurately characterize the impact of the underwater environment on the system's electrical characteristics. Third, existing parameter optimization methods often focus on maximizing efficiency alone, without considering engineering requirements such as rated output power, coil material costs, and inverter soft-switching implementation. Furthermore, they do not deeply couple the eddy current loss model with the optimization process, making it difficult to achieve global optimum results. Summary of the Invention

[0004] This invention addresses the problems of existing technologies by providing a parameter optimization method for underwater wireless power transfer systems based on high-precision eddy current loss modeling. The technical solution adopted is as follows: Firstly, a parameter optimization method for an underwater wireless power transfer system based on high-precision eddy current loss modeling includes: S1. Based on Maxwell's equations, establish an electromagnetic field distribution model for the transmitting and receiving coils in an underwater conductive medium environment. By solving for the additional self-resistance and additional mutual resistance introduced by eddy current loss and the total eddy current loss, complete the eddy current loss modeling. S2, determine the independent design parameters affecting eddy current loss based on the eddy current loss modeling, and complete the basic electrical parameter modeling of the planar helical coil based on the independent design parameters; S3, the underwater conductive medium is equivalent to an independent electrical port, an equivalent circuit model is established, and the calculation expressions for the system input impedance, output power and transmission efficiency are derived; wherein, the equivalent circuit model includes the additional resistance and additional inductance introduced by the eddy current loss; S4. Based on the optimization objective, a multi-objective optimization function is constructed by establishing inequality constraints that include the inverter's zero-voltage soft-switching condition, the maximum outer diameter limit of the coil, and the current density limit of the coil conductor. S5. After satisfying the inequality constraints, the global optimal solution for the independent design parameters is obtained by iteratively solving the problem using a metaheuristic optimization algorithm based on the multi-objective optimization function.

[0005] In some implementations, the conditions for establishing the electromagnetic field distribution model in S1 include: S101, obtain linear, isotropic, and data on conductivity, dielectric constant, and magnetic permeability of seawater medium; S102, Based on the linear data of the seawater medium, when the electromagnetic field distribution model is infinitely extended in the XY plane and limited to the region between the transmitting coil and the receiving coil in the Z-axis direction; S103, Based on the isotropic conductivity and dielectric constant data, when the transmitting coil and the receiving coil are coaxially aligned along the Z-axis and without offset, the electromagnetic field distribution model is established; S104. Based on the permeability data, when a sinusoidal alternating current is applied to the coil, the electromagnetic field distribution model is established.

[0006] In some implementations, in S1, based on the electromagnetic field distribution model, analytical expressions for the electric field intensity in different regions are derived and solved, specifically including: S111, Based on the Helmholtz equation in cylindrical coordinates, the analytical expression of the electric field intensity is solved by combining the method of separation of variables with the Bessel function; S112, determine the solution coefficients based on the region boundary conditions and the Bessel function expression of the δ function; S113, based on the analytical expression of the electric field strength and the solution coefficients, the azimuth electric field strength generated by the transmitting coil and the receiving coil in the water medium region is obtained.

[0007] In some implementations, in S2, the independent design parameters include the number of turns of the transmitting coil, the number of turns of the receiving coil, the turn spacing of the transmitting coil, the turn spacing of the receiving coil, the inner diameter of the transmitting coil, the inner diameter of the receiving coil, and the system resonant frequency.

[0008] In some implementations, in S4, the expression for the multi-objective optimization function is: ; in, This represents the actual output power of the system. The rated output power of the system, For the system's DC-DC transmission efficiency, The total copper mass of the transmitting and receiving coils, , , These are the output power weighting coefficient, efficiency weighting coefficient, and copper material quality weighting coefficient, respectively.

[0009] In some implementations, in S5, the metaheuristic optimization algorithm is implemented using a particle swarm optimization algorithm, and the iterative solution of the particle swarm optimization algorithm includes: S51, apply a penalty function to particles that violate the inequality constraints; S52, the penalty function is incorporated into the multi-objective optimization function to form the final cost function; S53, by iteratively updating the particle's velocity and position, solve for the globally optimal parameters corresponding to minimizing the cost function.

[0010] In some implementations, in S1, the total eddy current loss is calculated by volume integration over the water medium region. The total eddy current loss is divided into three parts: self-eddy current loss generated by the separate excitation of the transmitting coil, self-eddy current loss generated by the separate excitation of the receiving coil, and mutual eddy current loss generated by the joint excitation of the transmitting and receiving coils. The three parts of loss correspond to the power dissipation of the additional self resistance and the additional mutual resistance, respectively.

[0011] Secondly, embodiments of the present invention provide a parameter optimization device for an underwater wireless power transfer system based on high-precision eddy current loss modeling, comprising: The loss modeling module is used to establish an electromagnetic field distribution model of the transmitting and receiving coils in an underwater conductive medium environment based on Maxwell's equations. It completes the eddy current loss modeling by solving for the additional self-resistance and additional mutual resistance introduced by eddy current loss and the total eddy current loss. The parameter modeling module is used to determine the independent design parameters affecting eddy current loss based on the eddy current loss modeling, and to complete the basic electrical parameter modeling of the planar helical coil based on the independent design parameters. The circuit model module is used to treat the underwater conductive medium as an independent electrical port, establish an equivalent circuit model, and derive the calculation expressions for the system input impedance, output power, and transmission efficiency; wherein, the equivalent circuit model includes additional resistance and additional inductance introduced by the eddy current loss; The optimization function module is used to construct a multi-objective optimization function based on the optimization objective by establishing inequality constraints that include the inverter's zero-voltage soft-switching condition, the maximum outer diameter limit of the coil, and the current density limit of the coil conductor. The global optimization module is used to obtain the global optimal solution of the independent design parameters by iteratively solving the multi-objective optimization function through a metaheuristic optimization algorithm after satisfying the inequality constraints.

[0012] Thirdly, embodiments of the present invention provide an electronic device, including a memory and a processor, wherein the memory is used to store one or more computer instructions, wherein when the one or more computer instructions are executed by the processor, they implement the method described in the first aspect above.

[0013] Fourthly, embodiments of the present invention provide a computer storage medium storing a computer program, which, when executed by a processor, implements the method described in the first aspect.

[0014] One or more embodiments of the present invention can bring at least the following beneficial effects: This invention establishes a full-dimensional analytical electromagnetic field model of eddy current loss, which can quantify the self-eddy current loss of the transmitting and receiving coils. At the same time, it derives the calculation method of mutual eddy current loss, solves the problem of large calculation error of eddy current loss under high-frequency conditions in the prior art, and provides high-precision loss model support for system design. The method of this invention is based on the eddy current loss model. By quantitatively correlating the core independent design parameters such as the number of coil turns, the turn spacing, the inner diameter, and the resonant frequency with the eddy current loss, the loss characteristics are directly integrated into the design process of the coil parameters, thereby suppressing the eddy current loss from the root. The method of this invention constructs a multi-objective optimization function that takes into account rated output power, system transmission efficiency, and the amount of copper material used in the coil. It also incorporates engineering constraints such as inverter ZVS soft switching, coil size, and current density. The global optimal solution is achieved through particle swarm optimization algorithm. Under the premise of ensuring the reliable operation of the rated output power and soft switching of the system, it can achieve synergistic optimization of maximizing efficiency and minimizing copper material usage. The design method of this invention is highly versatile, applicable not only to planar helical coil structures but also to helical coil structures and media environments with different conductivity levels, from freshwater to seawater. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the transmission space division structure of the underwater wireless power transmission system provided in an embodiment of the present invention; Figure 2 This is a circuit diagram of an underwater wireless power transfer system that treats eddy current loss as an external object, provided in an embodiment of the present invention. Figure 3 This is an equivalent circuit diagram of an underwater wireless power transmission system considering eddy current losses provided in an embodiment of the present invention; Figure 4 This is a flowchart of the underwater wireless power transfer system parameter optimization method based on high-precision eddy current loss modeling provided in the embodiments of the present invention; Figure 5 This is a schematic diagram of the underwater environment provided in an embodiment of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0018] Example 1: This embodiment provides a parameter optimization method for an underwater wireless power transfer system based on high-precision eddy current loss modeling, including: S1. Based on Maxwell's equations, establish an electromagnetic field distribution model for the transmitting and receiving coils in an underwater conductive medium environment. By solving for the additional self-resistance and additional mutual resistance introduced by eddy current loss and the total eddy current loss, complete the eddy current loss modeling. S2, determine the independent design parameters affecting eddy current loss based on the eddy current loss modeling, and complete the basic electrical parameter modeling of the planar helical coil based on the independent design parameters; S3, the underwater conductive medium is equivalent to an independent electrical port, an equivalent circuit model is established, and the calculation expressions for the system input impedance, output power and transmission efficiency are derived; wherein, the equivalent circuit model includes the additional resistance and additional inductance introduced by the eddy current loss; S4. Based on the optimization objective, a multi-objective optimization function is constructed by establishing inequality constraints that include the inverter's zero-voltage soft-switching condition, the maximum outer diameter limit of the coil, and the current density limit of the coil conductor. S5. After satisfying the inequality constraints, the global optimal solution for the independent design parameters is obtained by iteratively solving the problem using a metaheuristic optimization algorithm based on the multi-objective optimization function.

[0019] First, according to S1, an electromagnetic field distribution model for an underwater conductive medium environment is established based on Maxwell's equations. The system transmission space is divided into three sub-regions: Region 1 is the air region below the transmitting coil, Region 2 is the seawater region between the transmitting and receiving coils, and Region 3 is the air region above the receiving coil. Figure 1 As shown.

[0020] The modeling process uses the following assumptions: Seawater is a linear, isotropic medium with uniform electromagnetic properties in space; The seawater extends infinitely in the XY plane, but is confined between the transmitting and receiving coils in the Z-axis direction; The transmitting and receiving coils are planar spiral structures, coaxially aligned along the Z-axis, with no radial or angular offset; A sinusoidal alternating current is passed through the coil, and the effect of wire diameter on the electromagnetic field distribution is ignored.

[0021] Deriving the electric field intensity in space using Maxwell's equations: ; Where i = t and r refer to the transmitter and receiver, respectively, and j represents the sub-region. and These represent the magnetic field strength and magnetic induction intensity of coil i in region j, respectively. and Let represent the electric field strength and conduction current density of coil i in region j, respectively. This represents the electric displacement vector. , and Let be the electrical conductivity, dielectric constant, and magnetic permeability of region j, respectively. Through mathematical operations on Maxwell's equations, we can obtain the following expression, which is the Helmholtz equation for electric field intensity: ; in In cylindrical coordinates, the geometry of a planar helical coil is symmetrical, therefore The components in the radial and axial directions can be neglected. Therefore, the Helmholtz equation for the electric field intensity in cylindrical coordinates can be expressed as: ; By using the method of separation of variables Transform the Helmholtz equation into a partial differential equation: ; Further processing decomposes the partial differential equation into two ordinary differential equations: ; The electric field strength generated by the m-th turn of the transmitting coil in the seawater region is obtained by solving the above equations. The electric field strength generated by the nth turn of the receiving coil : ; ; The total electric field strength in the seawater region can be obtained by superimposing the electromagnetic intensities. : ; In the transmitting and receiving coils, the induced open-circuit voltages of the m-th and n-th turns with lengths of lm and ln, respectively, are: ; The sum of the induced voltages of all adjacent turns in the coil represents the total value of the induced voltage. Therefore, the induced open-circuit voltage of the coil is: ; Because the electrical conductivity of seawater is not zero, eddy current losses are generated under the action of an alternating magnetic field, thus... and It can be represented as: ; in , and This is the additional resistance caused by eddy current losses. Furthermore, since each turn of the coil is connected in series, the line current is equal, therefore the additional resistance of the coil is: The transmitting coil has added self-resistance : ; Additional self-resistance of the receiving coil : ; Additional mutual resistance : ; We perform a volume integral solution in cylindrical coordinates over the seawater region to calculate the additional losses caused by eddy current losses: ; Further expansion reveals that, ; in, and These are the additional losses generated by the transmitting coil and the receiving coil, respectively. It is the mutual eddy current loss generated between coils.

[0022] Furthermore, in S1, the conditions for establishing the electromagnetic field distribution model include: S101, obtain linear, isotropic, and data on conductivity, dielectric constant, and magnetic permeability of seawater medium; S102, Based on the linear data of the seawater medium, when the electromagnetic field distribution model is infinitely extended in the XY plane and limited to the region between the transmitting coil and the receiving coil in the Z-axis direction; S103, Based on the isotropic conductivity and dielectric constant data, when the transmitting coil and the receiving coil are coaxially aligned along the Z-axis and without offset, the electromagnetic field distribution model is established; S104. Based on the permeability data, when a sinusoidal alternating current is applied to the coil, the electromagnetic field distribution model is established.

[0023] Furthermore, in S1, based on the electromagnetic field distribution model, analytical expressions for the electric field intensity in different regions are derived and solved, specifically including: S111, Based on the Helmholtz equation in cylindrical coordinates, the analytical expression of the electric field intensity is solved by combining the method of separation of variables with the Bessel function; S112, determine the solution coefficients based on the region boundary conditions and the Bessel function expression of the δ function; S113, Based on the analytical expression for electric field strength and the solution coefficients, the azimuth electric field strength generated jointly by the transmitting and receiving coils within the water medium region is obtained. Next, based on the eddy current loss model established in S1, the independent design parameters affecting eddy current loss are determined as follows: number of turns of the transmitting coil. Number of turns of the receiving coil Transmitting coil turn spacing Receiver coil turn spacing Inner diameter of transmitting coil Inner diameter of the receiving coil System resonant frequency .

[0024] Based on the above independent design parameters, and following S2, complete the modeling of the coil's basic electrical parameters: The self-inductance parameters of the transmitting and receiving coils are: ; Where N is the number of turns of the coil, Do and Di are the outer and inner diameters of the coil in inches, respectively, and Lt and Lr are the self-inductance of the coil in μH.

[0025] The mutual inductance parameters between the transmitting and receiving coils are: ; in The permeability of free space, and These are the infinitesimal tangential vectors on the transmitting and receiving coils, respectively. The direct distance between them. The unit of mutual inductance between the transmitting and receiving coils is μH.

[0026] The AC resistance of the coil is: ; Where G is a dimensionless correction factor. The total length of the conductor. Let be the conductivity of the copper wire. The effective cross-sectional area of ​​the conductor. , , and These are dimensionless correction factors for the number of turns, skin effect, turn spacing, and frequency, respectively.

[0027] Zero-voltage switching (ZVS) conditions for inverters: To ensure efficient and stable inverter operation, it is necessary to maintain a minimum phase lag between the voltage and current of the transmitting coil. This enables zero-voltage turn-on of power devices, eliminates switching losses, and suppresses electromagnetic interference. The minimum phase lag angle is: ; in: For system efficiency, The output capacitor of the MOSFET. This is a parallel buffer capacitor for the MOSFET. Input voltage, For the switch dead time, This is the system's rated output power.

[0028] Next, following S3, the derivation of the analytical expression for the electric field intensity is based on the Helmholtz equation in cylindrical coordinates. Utilizing the axisymmetric properties of the planar helical coil, the radial and axial components of the electric field are ignored, retaining only the azimuth component. The partial differential equation is decomposed into two ordinary differential equations using the method of separation of variables. The general solution is solved using the exponential function and the first-order Bessel function, respectively. The general solution coefficients are determined by combining the boundary conditions of the region and the Bessel function integral form of the δ function, finally obtaining the total electric field intensity in the water medium region.

[0029] Furthermore, in step S1, the total eddy current loss is calculated by integrating the ohmic loss over the volume of the water medium, and the expression is: ; in, The conductivity of the water medium, V represents the total azimuth electric field intensity within the seawater medium region, and V represents the volume of the water medium. The total eddy current loss is decomposed into three parts: the self-eddy current loss of the transmitting coil, the self-eddy current loss of the receiving coil, and the mutual eddy current loss, which correspond to the power dissipation of the additional self-resistance on the transmitting side, the additional self-resistance on the receiving side, and the additional mutual resistance, respectively.

[0030] Next, according to S3, in the lumped equivalent circuit model, the influence of the water medium on the transmitting coil and the receiving coil is equivalent to the reflection impedance. The equivalent self-impedance of the transmitting side, the equivalent self-impedance of the receiving side, and the equivalent mutual impedance all include the inherent impedance when there is no underwater medium and the reflection impedance of the water medium. Among them, the real part of the reflection impedance is the additional resistance introduced by eddy current loss, and the imaginary part is the additional inductance introduced by eddy current loss. The additional inductance slightly reduces the equivalent self-inductance and mutual inductance of the coil.

[0031] Next, according to S4, the expression for the multi-objective optimization function is: ; in It is the total copper mass. , , These are the weighting coefficients, and Set the value to 1 to ensure that the system output power meets the rated value requirement; the specific inequality constraint conditions are as follows: ZVS constraint: The phase lag angle of the inverter arm output voltage and current satisfies the soft-switching start condition; Size constraints: The maximum outer diameter of the transmitting coil and the receiving coil shall not exceed 250 mm; Current density constraint: The peak current density of the coil conductor shall not exceed 6 × 10⁻⁶. 6 A / m 2 .

[0032] Furthermore, the expression for the multi-objective optimization function is: ; in, This represents the actual output power of the system. The rated output power of the system, For the system's DC-DC transmission efficiency, The total copper mass of the transmitting and receiving coils, , , These are the output power weighting coefficient, efficiency weighting coefficient, and copper material quality weighting coefficient, respectively.

[0033] Next, according to S5, the metaheuristic optimization algorithm is implemented using the particle swarm optimization algorithm, and the iterative solution of the particle swarm optimization algorithm includes: S51, apply a penalty function to particles that violate the inequality constraints; S52, the penalty function is incorporated into the multi-objective optimization function to form the final cost function; S53, by iteratively updating the particle's velocity and position, solve for the globally optimal parameters corresponding to minimizing the cost function.

[0034] The particle swarm optimization algorithm is used for iterative solution. The optimization process is as follows: Figure 4 As shown, the specific steps are as follows: S531, Initialization and Requirements Definition; Define the design constraints and objectives of the system and optimization algorithm: Electrical specifications: Input voltage Load voltage Load current Target output power Minimum phase lag required to achieve ZVS Physical constraints: characteristics of the coupling medium and range of values ​​for coil geometric parameters.

[0035] Generate the initial particle swarm: Randomly assign a set of independent design parameters to each particle. and its increment ,in For the number of coil turns, For coil spacing, For coil radius, It is the resonant frequency.

[0036] S532, Electromagnetic parameter calculation; Based on the current geometric and electrical parameters of the particles, calculate the self-inductance, mutual inductance, self-impedance, mutual impedance, and compensation capacitance of the coil, and establish the electromagnetic model of the system.

[0037] S533, System Performance Evaluation Based on the electromagnetic model, the system's output power, transmission efficiency, and input / output impedance characteristics are calculated under current parameters. An objective function is constructed to quantify the deviation between the current particle solution and the design objective; simultaneously, the actual phase lag of the transmitting coil current and voltage is verified to ensure that the ZVS constraint is met.

[0038] S534, Constraint Handling and Cost Function Construction A penalty function is introduced to penalize parameter solutions that violate physical constraints, performance boundaries, or ZVS phase conditions. Combining the objective function and the penalty function, a final cost function is defined as the evaluation criterion for parameter quality.

[0039] S535, Parameter Update and Iteration Judgment Update the design parameters of each particle according to the velocity-position update rule of the particle swarm optimization algorithm. Determine the current iteration number. Is it less than the maximum number of iterations? : If the conditions are met: return to the electromagnetic parameter calculation step and proceed to the next iteration.

[0040] If the conditions are not met: terminate the iteration and output the optimal parameters of the system.

[0041] Based on the optimal solution of the obtained independent design parameters, the self-inductance of the transmitting coil is calculated according to the basic parameter formula of S2. The receiving coil's self-inductance According to the condition of series resonance Calculate the series compensation capacitors at the transmitter and receiver. , .

[0042] Example 2: This invention provides a parameter optimization device for an underwater wireless power transfer system based on high-precision eddy current loss modeling, comprising: The loss modeling module is used to establish an electromagnetic field distribution model of the transmitting and receiving coils in an underwater conductive medium environment based on Maxwell's equations. It completes the eddy current loss modeling by solving for the additional self-resistance and additional mutual resistance introduced by eddy current loss and the total eddy current loss. The parameter modeling module is used to determine the independent design parameters affecting eddy current loss based on the eddy current loss modeling, and to complete the basic electrical parameter modeling of the planar helical coil based on the independent design parameters. The circuit model module is used to treat the underwater conductive medium as an independent electrical port, establish an equivalent circuit model, and derive the calculation expressions for the system input impedance, output power, and transmission efficiency; wherein, the equivalent circuit model includes additional resistance and additional inductance introduced by the eddy current loss; The optimization function module is used to construct a multi-objective optimization function based on the optimization objective by establishing inequality constraints that include the inverter's zero-voltage soft-switching condition, the maximum outer diameter limit of the coil, and the current density limit of the coil conductor. The global optimization module is used to obtain the global optimal solution of the independent design parameters by iteratively solving the multi-objective optimization function through a metaheuristic optimization algorithm after satisfying the inequality constraints.

[0043] Example 3: This embodiment also provides an electronic device, including a memory and a processor, wherein the memory is used to store one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the method of Embodiment 1; In practical applications, the processor can be implemented as an Application Specific Integrated Circuit (ASIC), Digital Signal Processor (DSP), Digital Signal Processing Device (DSPD), Programmable Logic Device (PLD), Field Programmable Gate Array (FPGA), controller, microcontroller unit (MCU), microprocessor, or other electronic components to execute the methods described in the above embodiments.

[0044] The method implemented in this embodiment is as described in Embodiment 1.

[0045] Example 4: This embodiment also provides a computer storage medium storing a computer program, which, when executed by one or more processors, implements the method of Embodiment 1. The computer-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0046] The method implemented in this embodiment is as described in Embodiment 1.

[0047] In the several embodiments provided in this invention, it should be understood that the disclosed systems and methods can also be implemented in other ways. The system and method embodiments described above are merely illustrative.

[0048] It should be noted that, in this document, the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0049] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and variations in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection for this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A parameter optimization method for an underwater wireless power transfer system based on high-precision eddy current loss modeling, characterized in that, include: S1. Based on Maxwell's equations, establish an electromagnetic field distribution model for the transmitting and receiving coils in an underwater conductive medium environment. By solving for the additional self-resistance and additional mutual resistance introduced by eddy current loss and the total eddy current loss, complete the eddy current loss modeling. S2, determine the independent design parameters affecting eddy current loss based on the eddy current loss modeling, and complete the basic electrical parameter modeling of the planar helical coil based on the independent design parameters; S3, the underwater conductive medium is equivalent to an independent electrical port, an equivalent circuit model is established, and the calculation expressions for the system input impedance, output power and transmission efficiency are derived; wherein, the equivalent circuit model includes the additional resistance and additional inductance introduced by the eddy current loss; S4. Based on the optimization objective, a multi-objective optimization function is constructed by establishing inequality constraints that include the inverter's zero-voltage soft-switching condition, the maximum outer diameter limit of the coil, and the current density limit of the coil conductor. S5. After satisfying the inequality constraints, the global optimal solution for the independent design parameters is obtained by iteratively solving the problem using a metaheuristic optimization algorithm based on the multi-objective optimization function.

2. The method according to claim 1, characterized in that, In S1, the conditions for establishing the electromagnetic field distribution model include: S101, obtain linear, isotropic, and conductivity, dielectric constant, and magnetic permeability data of seawater medium; S102, Based on the linear data of the seawater medium, when the electromagnetic field distribution model is infinitely extended in the XY plane and limited to the region between the transmitting coil and the receiving coil in the Z-axis direction; S103, Based on the isotropic conductivity and dielectric constant data, when the transmitting coil and the receiving coil are coaxially aligned along the Z-axis and without offset, the electromagnetic field distribution model is established; S104. Based on the permeability data, when a sinusoidal alternating current is applied to the coil, the electromagnetic field distribution model is established.

3. The method according to claim 1, characterized in that, In S1, based on the electromagnetic field distribution model, analytical expressions for the electric field intensity in different regions are derived and solved, specifically including: S111, Based on the Helmholtz equation in cylindrical coordinates, the analytical expression of the electric field intensity is solved by combining the method of separation of variables with the Bessel function; S112, determine the solution coefficients based on the region boundary conditions and the Bessel function expression of the δ function; S113, based on the analytical expression of the electric field strength and the solution coefficients, the azimuth electric field strength generated by the transmitting coil and the receiving coil in the water medium region is obtained.

4. The method according to claim 1, characterized in that, In S2, the independent design parameters include the number of turns of the transmitting coil, the number of turns of the receiving coil, the turn spacing of the transmitting coil, the turn spacing of the receiving coil, the inner diameter of the transmitting coil, the inner diameter of the receiving coil, and the system resonant frequency.

5. The method according to claim 1, characterized in that, In S4, the expression for the multi-objective optimization function is: ； in, This represents the actual output power of the system. The rated output power of the system, For the system's DC-DC transmission efficiency, The total copper mass of the transmitting and receiving coils, , , These are the output power weighting coefficient, efficiency weighting coefficient, and copper material quality weighting coefficient, respectively.

6. The method according to claim 1, characterized in that, In S5, the metaheuristic optimization algorithm is implemented through a particle swarm optimization algorithm, and the iterative solution of the particle swarm optimization algorithm includes: S51, apply a penalty function to particles that violate the inequality constraints; S52, the penalty function is incorporated into the multi-objective optimization function to form the final cost function; S53, by iteratively updating the particle's velocity and position, solve for the globally optimal parameters corresponding to minimizing the cost function.

7. The method according to claim 1, characterized in that, In S1, the total eddy current loss is calculated by volume integration over the water medium region. The total eddy current loss is divided into three parts: self-eddy current loss generated by the separate excitation of the transmitting coil, self-eddy current loss generated by the separate excitation of the receiving coil, and mutual eddy current loss generated by the joint excitation of the transmitting and receiving coils. The three parts of loss correspond to the power dissipation of the additional self resistance and the additional mutual resistance, respectively.

8. A parameter optimization device for an underwater wireless power transfer system based on high-precision eddy current loss modeling, characterized in that, include: The loss modeling module is used to establish an electromagnetic field distribution model of the transmitting and receiving coils in an underwater conductive medium environment based on Maxwell's equations. It completes the eddy current loss modeling by solving for the additional self-resistance and additional mutual resistance introduced by eddy current loss and the total eddy current loss. The parameter modeling module is used to determine the independent design parameters affecting eddy current loss based on the eddy current loss modeling, and to complete the basic electrical parameter modeling of the planar helical coil based on the independent design parameters. The circuit model module is used to treat the underwater conductive medium as an independent electrical port, establish an equivalent circuit model, and derive the calculation expressions for the system input impedance, output power, and transmission efficiency; wherein, the equivalent circuit model includes additional resistance and additional inductance introduced by the eddy current loss; The optimization function module is used to construct a multi-objective optimization function based on the optimization objective by establishing inequality constraints that include the inverter's zero-voltage soft-switching condition, the maximum outer diameter limit of the coil, and the current density limit of the coil conductor. The global optimization module is used to obtain the global optimal solution of the independent design parameters by iteratively solving the multi-objective optimization function through a metaheuristic optimization algorithm after satisfying the inequality constraints.

9. An electronic device, characterized in that, The device includes a memory and a processor, the memory being used to store one or more computer instructions, wherein the one or more computer instructions, when executed by the processor, implement the method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, is used to implement the method as described in any one of claims 1-7.

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