Method and system for calculating inter-coil transmission efficiency of a wireless charging coupling mechanism

Abstract

The application provides a kind of wireless charging coupling mechanism's inter-coil transmission efficiency calculation method and system, can accurately calculate the inter-coil transmission efficiency of coupling mechanism, provide guarantee for evaluating the transmission efficiency of wireless charging system, method includes the following steps: simulating modeling to wireless charging coupling mechanism, the device included in coupling mechanism simulation model includes: the coil of transmitting end and receiving end, ferrite core and aluminum shielding plate;Obtain the device parameters of coupling mechanism simulation model;Based on the obtained device parameters, the quality factor of transmitting end and receiving end is calculated from the energy of wireless charging resonant circuit, the inter-coil transmission efficiency is obtained based on quality factor calculation, and the inter-coil transmission efficiency is used to measure the efficiency of wireless charging system.

Description

Technical Field

[0001] This invention relates to the field of wireless charging efficiency calculation and evaluation, and specifically to a method and system for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism. Background Technology

[0002] Due to the increasing severity of environmental problems and the energy crisis, electric vehicles are gaining popularity. The rapid development and widespread application of electric vehicles globally are accelerating the commercial application of Wireless Power Transfer (WPT) technology in wireless charging. Wireless charging offers high reliability, safety, and convenience, making it particularly suitable for future autonomous driving technologies.

[0003] Magnetic coupling WPT (MC-WPT), or inductive power transfer (IPT), transmits power through a magnetic field, offering a combination of high power, high efficiency, and long distance. This method is currently the most popular and widely used WPT technology, especially suitable for wireless charging of electric vehicles.

[0004] Car wireless charging system such as Figure 1 As shown, it is mainly divided into a transmitter and a receiver. The transmitter consists of a power supply, an inverter, a compensation network, and a transmitting coil; the receiver consists of a receiving coil, a compensation network, an inverter, and a load. The transmitting coil, receiving coil, ferrite, and aluminum plate constitute the wireless charging coupling mechanism.

[0005] System transmission efficiency is a crucial metric for wireless charging systems. It is influenced by numerous factors, among which the inter-coil transmission efficiency of the coupling mechanism is paramount. η It can be calculated from equation (1):

[0006] (1);

[0007] In the formula, k The coupling coefficient is the coupling factor of the coupling mechanism. Q 1 represents the transmitter quality factor. Q 2 represents the receiver quality factor. Of the parameters mentioned above, k The quality factor can be obtained from finite element simulation of the coupling mechanism. Q 1 and Q The simulation calculation for 2 is quite difficult.

[0008] It can be seen that the quality factor Q The calculation of the efficiency is the basis for determining the transmission efficiency between the coils of the coupling mechanism, and it is also an important prerequisite for evaluating the efficiency of the entire wireless charging system. In the series resonant circuit, the parameter definition of the quality factor of the series circuit is as follows: The ratio of the characteristic impedance of the resonant circuit to the circuit resistance is called the quality factor of the circuit, as shown in equation (2):

[0009] (2);

[0010] In the formula, the angular frequency ω = 2π f , f (Hz) represents frequency; L (H) represents inductance; R (Ω) represents the equivalent resistance of the coil.

[0011] In the coupling mechanism, the angular frequency ω and the coil inductance L The equivalent resistance of the coil is known, but calculating it is difficult. (Equivalent resistance of the coil) R It consists of 3 parts: a) the DC resistance of the coil R dc Coil proximity effect loss equivalent resistance R j Coil skin effect loss equivalent resistance R f b) Ferrite loss R C c) Eddy current loss of aluminum shielding plate R e.

[0012] Due to the complex structure of the coupling mechanism and the strong nonlinearity of ferrite losses, it is very difficult to accurately calculate the equivalent resistance of each part. Ultimately, the equivalent resistance of the entire coupling mechanism system cannot be calculated using the definition method of equation (2).

[0013] Previous literature has employed two methods for calculating the Q factor of the coupling mechanism: a) ignoring the influence of ferrite, i.e., not adding ferrite in the experiment; b) adding ferrite in the experiment, but only providing the trend of Q change, ignoring or avoiding the specific calculation of Q. The accuracy of the system transmission efficiency obtained using these methods for wireless charging systems is poor. Therefore, a method is urgently needed to effectively calculate the quality factor of the coupling mechanism, providing assurance for evaluating the efficiency of wireless charging systems. Summary of the Invention

[0014] To address the aforementioned problems, this invention provides a method and system for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism. This method can accurately calculate the inter-coil transmission efficiency of the coupling mechanism, providing assurance for evaluating the transmission efficiency of a wireless charging system.

[0015] The technical solution is as follows: A method for calculating the transmission efficiency between coils of a wireless charging coupling mechanism, characterized by the following steps:

[0016] A simulation model of the wireless charging coupling mechanism is performed. The components included in the simulation model of the coupling mechanism are: coils at the transmitting end and the receiving end, ferrite cores and aluminum shielding plates.

[0017] Obtain the device parameters of the simulation model of the coupling mechanism;

[0018] Based on the obtained device parameters, the quality factors of the transmitter and receiver are calculated from the energy of the wireless charging resonant circuit. The quality factor is calculated using the following formula:

[0019] ;

[0020] in, For frequency;

[0021] The inter-coil transmission efficiency is calculated based on the quality factor and is used to measure the efficiency of the wireless charging system.

[0022] Furthermore, when calculating the quality factor, the energy storage of the wireless charging resonant circuit includes the electrical and magnetic energy stored in the coil.

[0023] Furthermore, the electrical energy stored in the coil is calculated using the following formula:

[0024] ;

[0025] In the formula, Re means taking the real part of the complex number. E Here, * represents the electric field strength, and * represents the complex conjugate matrix. D Let d be the electric flux density, and d be the differential sign. V This represents the volume of the coil.

[0026] Furthermore, the magnetic energy stored in the coil is calculated using the following formula:

[0027] ;

[0028] In the formula, Re means taking the real part of the complex number. H ρ represents the magnetic field strength, and * represents the complex conjugate matrix. B Let d be the magnetic flux density and d be the differential sign. V This represents the volume of the coil.

[0029] Furthermore, when calculating the quality factor, the losses of the wireless charging resonant circuit considered in one cycle include coil losses, core losses, and aluminum shielding plate losses.

[0030] Furthermore, the coil loss is calculated using the following formula:

[0031] ;

[0032] In the formula, Re means taking the real part of the complex number. E Here, * represents the electric field strength, and * represents the complex conjugate matrix. J For current density, V This represents the volume of the coil.

[0033] Furthermore, the core loss is calculated using the following formula:

[0034] ;

[0035] In the formula, C m x and y are loss coefficients, determined by the properties of the ferrite material. f For frequency, B m denoted as the magnetic flux density amplitude, and n represents the number of grids into which the core is divided using the finite element method.

[0036] Furthermore, the loss of the aluminum shielding plate is calculated using the following formula:

[0037] ;

[0038] In the formula, Re means taking the real part of the complex number, and E Al The electric field strength on the aluminum shielding plate, * is the complex conjugate matrix, J AL This represents the current density on the aluminum shielding plate. V AL This refers to the volume of the aluminum shielding plate.

[0039] Inter-coil transmission efficiency η The following calculations were performed:

[0040] ;

[0041] In the formula, k The coupling coefficient is the coupling factor of the coupling mechanism. Q 1 represents the quality factor of the transmitter. Q 2 represents the quality factor of the receiving end.

[0042] A system for estimating the inter-coil transmission efficiency of a wireless charging coupling mechanism, characterized in that it comprises:

[0043] The simulation module is used to simulate and model the wireless charging coupling mechanism. The components included in the simulation model of the coupling mechanism are: coils at the transmitting end and the receiving end, ferrite core and aluminum shielding plate.

[0044] The parameter acquisition module is used to acquire the device parameters of the simulation model of the coupling mechanism;

[0045] The quality factor calculation module calculates the quality factor of the transmitter and receiver based on the device parameters obtained by the parameter acquisition module. The quality factor is calculated using the following formula:

[0046] ;

[0047] in, For frequency;

[0048] The inter-coil transmission efficiency calculation module calculates the inter-coil transmission efficiency based on the quality factor, and the inter-coil transmission efficiency is used to measure the performance of the wireless charging system.

[0049] A computer device, characterized in that it comprises: a processor, a memory, and a program;

[0050] The program is stored in the memory, and the processor calls the program stored in the memory to execute the above-described method for calculating the inter-coil transmission efficiency of the wireless charging coupling mechanism.

[0051] A computer-readable storage medium, characterized in that: the computer-readable storage medium is used to store a program for executing the above-described method for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism.

[0052] This invention provides a method for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism. It employs an energy definition method, dividing the maximum energy stored in the resonant circuit during wireless charging by the circuit's losses over one cycle. Based on finite element analysis, this invention incorporates the electrical and magnetic energy stored in the coils as the energy storage of the wireless charging resonant circuit. Furthermore, it calculates coil losses, core losses, and aluminum shielding plate losses using finite element analysis, thereby effectively calculating the quality factor of the coupling mechanism. This provides a basis for further evaluating the efficiency of the wireless charging system. Obtaining accurate inter-coil transmission efficiency allows for accurate assessment of the wireless charging system's efficiency, helping to accurately reflect the true energy transmission situation and providing a theoretical basis for the design and manufacturing of wireless charging systems. It also helps in accurately evaluating the mutual interference between the wireless charging system and the power grid. The accurate inter-coil transmission efficiency provides valuable reference and theoretical guidance for optimizing system parameters and improving the transmission performance of the wireless charging coupling mechanism, thus promoting the further development of wireless power transmission technology. Attached Figure Description

[0053] Figure 1 A schematic diagram of a wireless charging system for automobiles;

[0054] Figure 2 A schematic diagram of a simulation model of a wireless charging coupling mechanism;

[0055] Figure 3 A schematic diagram confirming the simulation model of the wireless charging coupling mechanism;

[0056] Figure 4 This is a schematic diagram illustrating the steps of a method for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism in an embodiment.

[0057] Figure 5 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0058] As described in the background section, the commonly used definitional method for calculating the quality factor is not suitable for systems with complex equivalent impedances, such as wireless charging coupling mechanisms. The definitional method, a common approach for calculating Q, is only applicable to systems with constant or linearly changing equivalent resistance. Wireless charging coupling systems contain ferrites, which exhibit characteristics such as magnetic saturation and hysteresis loss. The equivalent resistance of ferrites is non-linear and difficult to express using a fixed analytical formula. Ultimately, this means the equivalent resistance of the entire coupling mechanism system cannot be calculated using the definitional method.

[0059] In view of this, see Figure 4 This invention provides a method for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism, comprising the following steps:

[0060] Step 1: Simulate and model the wireless charging coupling mechanism. The components included in the simulation model of the coupling mechanism are: coils, ferrite cores and aluminum shielding plates of the transmitter and receiver.

[0061] Step 2: Obtain the device parameters of the coupling mechanism simulation model;

[0062] Step 3: Based on the obtained device parameters, calculate the quality factor of the transmitter and receiver from the energy of the wireless charging resonant circuit. The quality factor is calculated using the following formula:

[0063] ;

[0064] in, For frequency;

[0065] Step 4: Calculate the inter-coil transmission efficiency based on the quality factor. The inter-coil transmission efficiency is used to measure the efficiency of the wireless charging system.

[0066] In one embodiment of the present invention, in step 1, a simulation model of the wireless charging coupling mechanism is performed. Based on the actual structure, a finite element simulation model of the coupling mechanism is established after reasonable simplification. (See...) Figure 2 , Figure 3 The simulation model of the coupling mechanism includes the following components: transmitting coil 101, receiving coil 201, ferrite core 102, 202 and aluminum shielding plate 103, 203 at the transmitting and receiving ends, and a given coil current value.

[0067] In step 2, the device parameters of the coupling mechanism simulation model are obtained, including the electric field strength, current flux density, coil volume, magnetic field strength, magnetic flux density, current density, loss coefficient of the ferrite material, magnetic flux density amplitude of the iron core, field strength on the aluminum shield, current density on the aluminum shield, and volume of the aluminum shield. These device parameters can be directly read after the simulation is completed. The method of this invention is based on the finite element method, so these physical quantities of the coupling mechanism can be easily obtained in any finite element software capable of electromagnetic simulation.

[0068] In step 3, based on the obtained device parameters, the quality factors of the transmitter and receiver are calculated from the energy of the wireless charging resonant circuit. The quality factor is calculated using the following formula:

[0069] ;

[0070] When two resonant circuits with the same vibration frequency are placed together, and one circuit begins to oscillate when energized, the other circuit will also oscillate, automatically generating current, and electrical energy is thus transferred from a distance. This phenomenon is called magnetic resonance and is used in wireless charging.

[0071] The energy storage of a wireless charging resonant circuit includes both electrical and magnetic energy stored in the coil. Therefore, the calculation of the maximum energy storage of the wireless charging resonant circuit is divided into two parts.

[0072] Firstly, the electrical energy stored in the coil is calculated using the following formula:

[0073] ;

[0074] In the formula, Re means taking the real part of the complex number. E Here, * represents the electric field strength, and * represents the complex conjugate matrix. D Let d be the electric flux density, and d be the differential sign. V This represents the volume of the coil.

[0075] Secondly, the magnetic energy stored in the coil is calculated using the following formula:

[0076] ;

[0077] In the formula, Re means taking the real part of the complex number. H ρ represents the magnetic field strength, and * represents the complex conjugate matrix. B Let d be the magnetic flux density and d be the differential sign. V This represents the volume of the coil.

[0078] In this embodiment, when calculating the quality factor, the losses of the wireless charging resonant circuit considered in one cycle include coil losses, core losses, and aluminum shielding plate losses.

[0079] The coupling mechanism uses Litz wire, so skin effect losses can be ignored. Choosing Litz wire allows for an electric field distribution that considers proximity effects. The DC loss and proximity effect loss of the coil can then be calculated using the following formula:

[0080] ;

[0081] In the formula, Re means taking the real part of the complex number. E Here, * represents the electric field strength, and * represents the complex conjugate matrix. J For current density, V This represents the volume of the coil.

[0082] Core loss is calculated using the following formula:

[0083] ;

[0084] In the formula, C m x and y are loss coefficients, determined by the properties of the ferrite material. f For frequency, B m denoted as the magnetic flux density amplitude, and n represents the number of grids into which the core is divided using the finite element method.

[0085] The loss of the aluminum shielding plate is calculated using the following formula:

[0086] ;

[0087] In the formula, Re means taking the real part of the complex number, and E Al The electric field strength on the aluminum shielding plate, * is the complex conjugate matrix, J AL This represents the current density on the aluminum shielding plate. V AL This refers to the volume of the aluminum shielding plate.

[0088] Quality factor calculation: The magnetic energy and electrical energy stored in the coil, coil losses, core losses, and aluminum shielding losses are incorporated into the calculation of the quality factor Q.

[0089] ;

[0090] In the formula for Q, the numerator is energy in J, and the denominator is the calculated loss in W (watts). W = Pt (energy = loss * time = loss / unit time = loss * frequency), that is, W = P / f.

[0091] Thus, the quality factor of the coupling mechanism is obtained. Q Calculation formulas are used to calculate the transmitter quality factor. Q 1 and receiver quality factor Q 2.

[0092] Step 4: Calculate the inter-coil transmission efficiency based on the quality factor. The inter-coil transmission efficiency is used to measure the efficiency of the wireless charging system. η The following calculations were performed:

[0093] ;

[0094] In the formula, k The coupling coefficient is the coupling factor of the coupling mechanism. Q 1 represents the quality factor of the transmitter. Q 2 represents the quality factor at the receiver, and the quality factor at the transmitter is... Q 1 and receiver quality factor Q Substituting the values ​​into the formula, the transmission efficiency between coils can be calculated. η Inter-coil transmission efficiency η The inter-coil transmission efficiency (η) is a crucial metric for calculating the system transmission efficiency of a wireless charging system. By obtaining the accurate η, the overall efficiency of the wireless charging system can be accurately determined, helping to reconstruct the true state of power transmission and providing a theoretical basis for the design and manufacturing of wireless charging systems. It also helps to accurately assess the mutual interference between the wireless charging system and the power grid. The accurate inter-coil transmission efficiency provides valuable reference and theoretical guidance for optimizing system parameters in wireless charging coupling mechanisms and improving system transmission performance, thus further promoting the development of wireless power transfer technology.

[0095] The efficiency formula for the entire wireless transmission system can be defined as: , For the efficiency of each component in the system, it can be seen that when When the efficiency remains constant, design a larger inter-coil transmission efficiency. This can improve the overall system transmission efficiency. (Transmission efficiency between coils) It is one of the important evaluation indicators of wireless charging systems. The larger the value, the higher the energy transmission efficiency and the better the product performance.

[0096] Furthermore, a larger quality factor Q and inter-coil transmission efficiency Design is the prerequisite and foundation for the high-efficiency design of the entire wireless charging system. Using the method for calculating the inter-coil transmission efficiency of the wireless charging coupling mechanism of this invention, the quality factor Q and the inter-coil transmission efficiency can be calculated. In the early stages of designing the transmitter and receiver of a wireless charging coupling mechanism, Q can serve as a key indicator for evaluating the rationality of the design. For example, setting Q=500 as the design threshold, a transmitter-receiver design with Q≥500 is considered reasonable; otherwise, it is considered unreasonable.

[0097] Applying the method proposed in this invention to Figure 2The wireless charging coupling mechanism shown in the figure has coil energy storage and loss calculated through simulation, as shown in Table 1.

[0098] Table 1 shows the coil energy storage and losses calculated using the method of this invention.

[0099]

[0100] Since the Q value of any coupling mechanism is affected by various factors, the Q value of the same model coupling mechanism is not unique and will fluctuate within a certain range. Table 1 shows the fluctuation range of the actual measured Q values. Values ​​calculated using the method of this invention that fall within this range can be considered correct and reliable. This is indeed how it is done in the actual product design stage and has important reference value.

[0101] The result calculated using the method proposed in this invention Q The values ​​and the transmission efficiency between coils are consistent with the actual situation.

[0102] In an embodiment of the present invention, a system for estimating the inter-coil transmission efficiency of a wireless charging coupling mechanism is also provided, comprising:

[0103] Simulation module 1 is used to simulate and model the wireless charging coupling mechanism. The components included in the simulation model of the coupling mechanism are: coils at the transmitting end and the receiving end, ferrite core and aluminum shielding plate.

[0104] Parameter acquisition module 2 is used to acquire the device parameters of the coupling mechanism simulation model;

[0105] Quality factor calculation module 3 calculates the quality factor of the transmitter and receiver based on the device parameters obtained by the parameter acquisition module. The quality factor is calculated using the following formula:

[0106] ;

[0107] in, For frequency;

[0108] The coil-to-coil transmission efficiency calculation module 4 calculates the coil-to-coil transmission efficiency based on the quality factor. The coil-to-coil transmission efficiency is used to measure the performance of the wireless charging system.

[0109] In an embodiment of the present invention, a computer device is also provided, comprising: a processor, a memory, and a program;

[0110] The program is stored in memory, and the processor calls the program stored in memory to execute the above-mentioned method for calculating the transmission efficiency between coils of the wireless charging coupling mechanism.

[0111] The computer device can be a terminal, and its internal structure diagram can be as follows: Figure 5 As shown, the computer device includes a processor, memory, network interface, display screen, and input devices connected via a bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used for communication with external terminals via a network connection. When executed by the processor, the computer program calculates the inter-coil transmission efficiency of the wireless charging coupling mechanism. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the computer device casing, or an external keyboard, touchpad, or mouse.

[0112] Memory can be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), and Electrically Erasable Programmable Read-Only Memory (EEPROM). Memory stores programs, and the processor executes these programs after receiving execution instructions.

[0113] A processor can be an integrated circuit chip with signal processing capabilities. The aforementioned processor can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc. The processor can also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. A general-purpose processor can be a microprocessor or any conventional processor.

[0114] Those skilled in the art will understand that Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. A specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0115] In an embodiment of the present invention, a computer-readable storage medium is also provided for storing a program for executing the above-described method for calculating the inter-coil transmission efficiency of the wireless charging coupling mechanism.

[0116] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, computer devices, or computer program products. Therefore, embodiments of the present invention can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of the present invention can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0117] Embodiments of the present invention are described with reference to flowchart illustrations of methods, computer apparatuses, or computer program products according to embodiments of the invention. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, create means for implementing the functions specified in the flowchart.

[0118] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that implement the functions specified in the flowchart.

[0119] The above provides a detailed description of the calculation method, system, computer device, and computer-readable storage medium application of the wireless charging coupling mechanism provided by this invention. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A method for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism, characterized in that, Includes the following steps: A simulation model of the wireless charging coupling mechanism is performed. The components included in the simulation model of the coupling mechanism are: coils at the transmitting end and the receiving end, ferrite cores and aluminum shielding plates. Obtain the device parameters of the simulation model of the coupling mechanism; Based on the obtained device parameters, the quality factors of the transmitter and receiver are calculated from the energy of the wireless charging resonant circuit. The quality factor is calculated using the following formula: ； in, For frequency; The inter-coil transmission efficiency is calculated based on the quality factor, and the inter-coil transmission efficiency is used to measure the efficiency of the wireless charging system. When calculating the quality factor, the energy stored in a wireless charging resonant circuit includes both electrical and magnetic energy stored in the coil. The electrical energy stored in the coil is calculated using the following formula: ； In the formula, Re means taking the real part of the complex number. E Here, * represents the electric field strength, and * represents the complex conjugate matrix. D Let d be the electric flux density, and d be the differential sign. V The volume of the coil; The magnetic energy stored in the coil is calculated using the following formula: ； In the formula, Re means taking the real part of the complex number. H ρ represents the magnetic field strength, and * represents the complex conjugate matrix. B Let d be the magnetic flux density and d be the differential sign. V The volume of the coil; Inter-coil transmission efficiency η The following calculations were performed: ； In the formula, k The coupling coefficient is the coupling factor of the coupling mechanism. Q 1 represents the quality factor of the transmitter. Q 2 represents the quality factor of the receiving end.

2. The method for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism according to claim 1, characterized in that: When calculating the quality factor, the losses of the wireless charging resonant circuit considered in one cycle include coil losses, core losses, and aluminum shielding plate losses.

3. The method for calculating the inter-coil transmission efficiency of a wireless charging coupling mechanism according to claim 2, characterized in that: Coil losses are calculated using the following formula: ； In the formula, Re means taking the real part of the complex number. E Here, * represents the electric field strength, and * represents the complex conjugate matrix. J For current density, V Let d be the volume of the coil, and d be the differential sign. Core loss is calculated using the following formula: ； In the formula, C m x and y are loss coefficients, determined by the properties of the ferrite material. f For frequency, B m The magnetic flux density amplitude is represented by n, where n represents the number of grids into which the core is divided using the finite element method. The loss of the aluminum shielding plate is calculated using the following formula: ； In the formula, Re means taking the real part of the complex number, and E Al The electric field strength on the aluminum shielding plate, * is the complex conjugate matrix, J AL This represents the current density on the aluminum shielding plate. V AL Let d be the volume of the aluminum shielding plate, and d be the differential symbol.

4. A system for estimating the inter-coil transmission efficiency of a wireless charging coupling mechanism, characterized in that, include: The simulation module is used to simulate and model the wireless charging coupling mechanism. The components included in the simulation model of the coupling mechanism are: coils at the transmitting end and the receiving end, ferrite core and aluminum shielding plate. The parameter acquisition module is used to acquire the device parameters of the simulation model of the coupling mechanism; The quality factor calculation module calculates the quality factor of the transmitter and receiver based on the device parameters obtained by the parameter acquisition module. The quality factor is calculated using the following formula: ； in, For frequency; The inter-coil transmission efficiency calculation module calculates the inter-coil transmission efficiency based on the quality factor. This inter-coil transmission efficiency is used to measure the performance of the wireless charging system. When calculating the quality factor, the energy stored in a wireless charging resonant circuit includes both electrical and magnetic energy stored in the coil. The electrical energy stored in the coil is calculated using the following formula: ； In the formula, Re means taking the real part of the complex number. E Here, * represents the electric field strength, and * represents the complex conjugate matrix. D Let d be the electric flux density, and d be the differential sign. V The volume of the coil; The magnetic energy stored in the coil is calculated using the following formula: ； In the formula, Re means taking the real part of the complex number. H ρ represents the magnetic field strength, and * represents the complex conjugate matrix. B Let d be the magnetic flux density and d be the differential sign. V The volume of the coil; Inter-coil transmission efficiency η The following calculations were performed: ； In the formula, k The coupling coefficient is the coupling factor of the coupling mechanism. Q 1 represents the quality factor of the transmitter. Q 2 represents the quality factor of the receiving end.

5. A computer device, characterized in that, It includes: a processor, memory, and programs; The program is stored in the memory, and the processor calls the program stored in the memory to execute the method for calculating the inter-coil transmission efficiency of the wireless charging coupling mechanism according to claim 1.

6. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a program for executing the method for calculating the inter-coil transmission efficiency of the wireless charging coupling mechanism according to claim 1.

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