Electromagnetic interference prediction methods, electromagnetic interference cancellation methods, terminals and storage media

Abstract

The present invention discloses an electromagnetic interference prediction method, an electromagnetic interference elimination method, a system control module production method, a terminal and a computer-readable storage medium, the method comprising: obtaining a cavity three-dimensional model according to a structural model of a system control module; obtaining the cavity medium of the cavity, and configuring the cavity medium conditions according to the cavity medium; obtaining the interference frequency of the PCB board according to the PCB board and the components installed on the PCB board; configuring the electromagnetic boundary conditions of the cavity three-dimensional model; performing simulation analysis on the cavity three-dimensional model according to the electromagnetic boundary conditions and the cavity medium conditions to obtain simulation results; judging whether there is an eigenfrequency in the cavity that is the same as the interference frequency; if there is, determining that the cavity will generate electromagnetic interference; if not, determining that the cavity will not generate electromagnetic interference. The present invention solves the problem that existing finished products or samples are required to perform cavity electromagnetic interference detection, resulting in increased production costs and reduced production efficiency.

Description

Technical Field

[0001] The present invention relates to the field of simulation, and in particular to an electromagnetic interference prediction method, an electromagnetic interference elimination method, a system control module production method, a terminal and a computer-readable storage medium. Background Art

[0002] In the process of system integration of terminals, the application of high-speed circuits is becoming more and more widespread, and the problem of electromagnetic interference is becoming more and more prominent. A big reason for this is that the high-frequency source on the circuit board causes resonance in the cavity between the circuit board and the metal plate in the terminal, forming a radiation effect, causing electromagnetic interference and affecting the operation of the circuit board. Now, generally, after the PCB board is produced on the production line and the components are installed and assembled with the metal plate, the finished product is tested to determine whether the cavity formed by the PCB board with installed components and the metal plate will generate electromagnetic interference. Once the electromagnetic interference performance of the finished product is found to be unqualified, the finished product needs to be adjusted, which will increase the cost of the production process and reduce production efficiency.

[0003] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0004] The main purpose of the present invention is to provide an electromagnetic interference prediction method, an electromagnetic interference elimination method, an electromagnetic interference elimination method, a system control module production method terminal and a computer-readable storage medium, aiming to solve the problem that existing finished products or samples are required to perform cavity electromagnetic interference detection, resulting in increased production costs and reduced production efficiency.

[0005] To achieve the above object, the present application provides an electromagnetic interference prediction method, comprising the steps of:

[0006] According to the structural model of the system control module, a three-dimensional model of the cavity in the system control module is obtained, wherein the system control module includes at least one PCB board and at least one metal plate, and the three-dimensional model of the cavity is a three-dimensional model of the cavity formed between two relatively arranged PCB boards and / or a three-dimensional model of the cavity formed between a relatively arranged PCB board and a metal plate;

[0007] Acquire the intracavitary medium of the cavity, and configure the intracavitary medium condition according to the intracavitary medium;

[0008] Obtain the interference frequency of the PCB board according to the PCB board and the components installed on the PCB board;

[0009] Configure electromagnetic boundary conditions for the 3D model of the cavity;

[0010] According to the electromagnetic boundary conditions and the medium conditions in the cavity, a three-dimensional model of the cavity is simulated and analyzed to obtain a simulation result, wherein the simulation result includes at least one eigenfrequency of the cavity;

[0011] Determine whether there is an eigenfrequency in the cavity that is the same as the interference frequency;

[0012] If it exists, it is determined that the cavity will generate electromagnetic interference;

[0013] If not present, it is determined that the cavity will not generate electromagnetic interference.

[0014] Optionally, the step of configuring the electromagnetic boundary conditions of the cavity three-dimensional model includes:

[0015] The surface in contact with the metal plate in the three-dimensional model of the cavity is set as a magnetic wall;

[0016] The surfaces in the cavity 3D model that are not in contact with the metal plate are set as electrical walls.

[0017] Optionally, the step of obtaining the interference frequency of the PCB board according to the PCB board and the components mounted on the PCB board includes:

[0018] Construct an equivalent circuit model based on the PCB board and the components installed on the PCB board;

[0019] The equivalent circuit model is simulated and calculated to obtain the interference frequency point of the PCB board.

[0020] Optionally, before the step of configuring the electromagnetic boundary conditions of the cavity three-dimensional model, the step further includes:

[0021] According to the three-dimensional model of the cavity, the size parameters of the cavity are obtained;

[0022] According to the size parameters of the cavity, the interference frequency of the medium in the cavity and the PCB board, it is judged whether the size parameters of the cavity meet the preset size conditions;

[0023] The step of configuring the electromagnetic boundary conditions of the cavity three-dimensional model comprises:

[0024] When the size parameters of the cavity meet the preset size conditions, the electromagnetic boundary conditions of the cavity three-dimensional model are configured.

[0025] Optionally, the step of performing simulation analysis on the cavity three-dimensional model according to the electromagnetic boundary conditions and the medium in the cavity to obtain the simulation result is:

[0026] Receive the convergence condition, the number of iterations, the minimum solution frequency and the number of modes to be solved input by the user;

[0027] According to the electromagnetic boundary conditions, the medium in the cavity, the convergence conditions, the number of iterations, the minimum solution frequency and the number of solution modes, the eigenmode simulation analysis of the cavity three-dimensional model is carried out to obtain the simulation results.

[0028] In addition, to achieve the above object, the present invention also provides an electromagnetic interference elimination method, comprising the steps of:

[0029] According to the structural model of the system control module, a three-dimensional model of the cavity in the system control module is obtained, wherein the system control module includes at least one PCB board and at least one metal plate, and the three-dimensional model of the cavity is a three-dimensional model of the cavity formed between two relatively arranged PCB boards and / or a three-dimensional model of the cavity formed between a relatively arranged PCB board and a metal plate;

[0030] Acquire the intracavitary medium of the cavity, and configure the intracavitary medium condition according to the intracavitary medium;

[0031] Obtain the interference frequency of the PCB board according to the PCB board and the components installed on the PCB board;

[0032] Configure electromagnetic boundary conditions for the 3D model of the cavity;

[0033] According to the electromagnetic boundary conditions and the medium conditions in the cavity, a three-dimensional model of the cavity is simulated and analyzed to obtain a simulation result, wherein the simulation result includes at least one eigenfrequency of the cavity;

[0034] Determine whether there is an eigenfrequency in the cavity that is the same as the interference frequency;

[0035] When there is an eigenfrequency in the cavity that is the same as the interference frequency, adjust the structural model of the system control module and return to execute: the structural model of the system control module, and obtain the three-dimensional model of the cavity in the system control module until it is determined that the cavity will not generate electromagnetic interference.

[0036] Optionally, the step of adjusting the structural model of the system control module includes:

[0037] At least one of adjusting the size parameters of the PCB board in the system control module, adjusting the distance between the PCB board and the metal plate relatively set in the system control module, adjusting the distance between two PCB boards relatively set in the system control module, and adjusting the size parameters of the metal plate in the system control module.

[0038] Optionally, the simulation result also includes an electric field distribution in the cavity corresponding to the eigenfrequency, and the step of adjusting the structural model of the system control module includes:

[0039] According to the intracavity electric field distribution corresponding to the eigenfrequency which is the same as the interference frequency point, the position corresponding to the maximum electric field strength value in the intracavity electric field distribution is taken as the short-circuit point position;

[0040] A three-dimensional model corresponding to a metal connector is added at the short-circuit point, where the metal connector is used to connect an oppositely disposed PCB board and a metal plate or to connect two oppositely disposed PCB boards.

[0041] In addition, to achieve the above object, the present invention also provides a system control module production method, comprising the steps of:

[0042] According to the structural model of the system control module, a three-dimensional model of the cavity in the system control module is obtained, wherein the three-dimensional model of the cavity is a three-dimensional model of the cavity formed between two PCB boards arranged opposite to each other and / or a three-dimensional model of the cavity formed between a PCB board and a metal plate arranged opposite to each other;

[0043] Acquire the intracavitary medium of the cavity, and configure the intracavitary medium condition according to the intracavitary medium;

[0044] Obtain the interference frequency of the PCB board according to the PCB board and the components installed on the PCB board;

[0045] Configure electromagnetic boundary conditions for the 3D model of the cavity;

[0046] According to the electromagnetic boundary conditions and the medium conditions in the cavity, a three-dimensional model of the cavity is simulated and analyzed to obtain a simulation result, wherein the simulation result includes at least one eigenfrequency of the cavity;

[0047] Determine whether there is an eigenfrequency in the cavity that is the same as the interference frequency;

[0048] If it does not exist, the system control module is produced according to the structural model of the system control module;

[0049] If it exists, the structural model of the system control module is adjusted, and the step of obtaining the three-dimensional model of the cavity in the system control module according to the structural model of the system control module is returned to be executed until it is determined that the cavity in the adjusted structural model of the system control module will not generate electromagnetic interference;

[0050] A system control module is produced according to the structural model of the system control module adjusted to correspond to the cavity not generating electromagnetic interference.

[0051] In addition, to achieve the above-mentioned purpose, the present invention also provides a terminal, which includes: a communication module, a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the computer program is executed by the processor, the steps of the electromagnetic interference prediction method as described above are implemented.

[0052] In addition, to achieve the above-mentioned purpose, the present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the electromagnetic interference prediction method as described above are implemented.

[0053] The embodiments of the present invention propose an electromagnetic interference prediction method, an electromagnetic interference elimination method, a production method of a system control module, a terminal and a computer-readable storage medium. The three-dimensional model of the cavity is obtained through the structural model of the system control module; the intracavity medium of the cavity is obtained, and the intracavity medium conditions are configured according to the intracavity medium; the interference frequency of the PCB board is obtained according to the PCB board and the components installed on the PCB board; the electromagnetic boundary conditions of the three-dimensional model of the cavity are configured; according to the electromagnetic boundary conditions and the intracavity medium conditions, the three-dimensional model of the cavity is simulated and analyzed to obtain simulation results; it is determined whether there is an eigenfrequency in the eigenfrequency of the cavity that is the same as the interference frequency; if so, it is determined that the cavity will generate electromagnetic interference; if not, it is determined that the cavity will not generate electromagnetic interference. Therefore, during the design stage of the system control module, it is possible to predict whether the cavity in the designed system control module will generate electromagnetic interference. This prediction method is an ex ante prediction. Even if the prediction result is that electromagnetic interference will be generated, only the design model of the system control module needs to be adjusted, and no adjustment is required to the finished product. This reduces the number and cost of subsequent adjustments to the finished product, and also reduces the unqualified rate of electromagnetic interference performance of the finished product, thereby avoiding increased costs and reduced production efficiency during the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a schematic diagram of the structure of the hardware operating environment involved in the embodiment of the present invention;

[0055] Figure 2 It is a flow chart of the first embodiment of the electromagnetic interference prediction method of the present invention;

[0056] Figure 3 It is a flow chart of a second embodiment of the electromagnetic interference prediction method of the present invention;

[0057] Figure 4 It is a flow chart of the first embodiment of the electromagnetic interference elimination method of the present invention;

[0058] Figure 5 It is a flow chart of the first embodiment of the system control module production method of the present invention.

[0059] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0060] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0061] Please refer to Figure 1 , Figure 1 Schematic diagram of the hardware structure of the terminal provided in each embodiment of the present invention, the terminal is a processing device, such as a computer device, which can be connected to any refrigeration device or user input device, and includes components such as a communication module 10, a memory 20 and a processor 30. Those skilled in the art can understand that Figure 1 The terminal shown in the figure may also include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently. The processor 30 is connected to the memory 20 and the communication module 10 respectively, and the memory 20 stores a computer program, which is executed by the processor 30 at the same time.

[0062] The communication module 10 can be connected to an external device through a network. The communication module 10 can receive data sent by an external device, and can also send data, instructions and information to the external device. The external device can be an electronic device such as a mobile phone, a tablet computer, a laptop computer, a desktop computer, etc.

[0063] The memory 20 can be used to store software programs and various data. The memory 20 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, an application required for at least one function (according to the structural model of the system control module, the three-dimensional model of the cavity in the system control module is obtained), etc.; the data storage area can store data or information created according to the use of the terminal, etc. In addition, the memory 20 can include a high-speed random access memory, and can also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0064] The processor 30 is the control center of the terminal. It uses various interfaces and lines to connect various parts of the entire terminal. It executes various functions of the terminal and processes data by running or executing software programs and / or modules stored in the memory 20, and calling data stored in the memory 20, so as to monitor the terminal as a whole. The processor 30 may include one or more processing units; preferably, the processor 30 may integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface, and application programs, and the modem processor mainly processes wireless communications. It is understandable that the above-mentioned modem processor may not be integrated into the processor 30.

[0065] although Figure 1 Although not shown, the terminal may further include a circuit control module for connecting to the mains to implement power control and ensure the normal operation of other components.

[0066] Those skilled in the art will understand that Figure 1 The terminal structure shown in the figure does not constitute a limitation on the terminal, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0067] Based on the above hardware structure, various embodiments of the method of the present invention are proposed.

[0068] Reference Figure 2 In a first embodiment of the electromagnetic interference prediction method of the present invention, the electromagnetic interference prediction method comprises the steps of:

[0069] Step S10, acquiring a three-dimensional model of a cavity in the system control module according to the structural model of the system control module, wherein the system control module includes at least one PCB board and at least one metal plate, and the three-dimensional model of the cavity is a three-dimensional model of a cavity formed between two relatively arranged PCB boards and / or a three-dimensional model of a cavity formed between a relatively arranged PCB board and a metal plate;

[0070] In this embodiment, the system control module refers to the core control module in the terminal, including at least one PCB board that plays a control role, and at least one metal plate that is assembled with the PCB board. For example, in a smart TV, the PCB board can be a movement board, a TCON board, or a power board, etc., and the metal plate can be a metal back plate of a TV or a metal heat sink mounted on the PCB board. The cavity refers to the cavity formed between two relatively arranged PCB boards in the system control module and / or the cavity formed between the relatively arranged PCB board and the metal plate. The structural model of the system control module can be a virtual three-dimensional structural model of a system control module that has been produced, or a virtual three-dimensional structural model of a system control module that has not been produced and is still in the design stage. According to the structural model of the system control module, the three-dimensional model of the cavity in the system control module can be obtained. The three-dimensional model of the cavity can be a three-dimensional model of the cavity formed between two relatively arranged PCB boards, and / or a three-dimensional model of the cavity formed between a relatively arranged PCB board and a metal plate. The process of the cavity three-dimensional model can be to extract the three-dimensional model of the cavity formed between the two relatively arranged PCB boards and / or the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate from the structural model of the constructed system control module by using the extraction technology in professional three-dimensional modeling software (such as Pro / E, CAD, UG, SolidWorks, etc.) or professional electromagnetic simulation software (such as HFSS, MICROWAVE STUDIO, Ansys Designer, etc.). It can also be to directly construct the three-dimensional model of the cavity formed between the two relatively arranged PCB boards in the system control module and / or the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate according to the design structure or actual structure of the system control module using the three-dimensional modeling function provided in professional three-dimensional modeling software (such as Pro / E, CAD, UG, SolidWorks, etc.) or professional electromagnetic simulation software (such as HFSS, MICROWAVE STUDIO, Ansys Designer, etc.), for example, using HFSS to directly construct the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate.

[0071] It should be noted that no matter the cavity 3D model is constructed directly in 3D modeling software or simulation software or the cavity 3D model is extracted through extraction technology, the surface of the obtained cavity 3D model may have some defects, such as surface mismatch, intersection and interference between surfaces, holes and gaps on the surface, etc. Before simulation, the surface needs to be preprocessed. According to the type of surface defects, the processing methods include manual repair, surface wrapping or surface reconstruction, and the preprocessed cavity 3D model is used as the simulation object.

[0072] Step S20, obtaining the intracavity medium of the cavity, and configuring the intracavity medium conditions according to the intracavity medium;

[0073] When performing electromagnetic field simulation, it is also necessary to configure the cavity medium conditions, that is, the material properties corresponding to the cavity three-dimensional model, such as relative magnetic permeability, relative dielectric constant, conductivity, dielectric loss tangent, magnetic loss tangent, relative magnetic permeability tensor, relative dielectric constant tensor, conductivity tensor, dielectric loss tangent tensor, magnetic loss tangent tensor and other parameters. These parameters are related to the medium in the cavity. Before simulating the cavity, you must first obtain the medium in the cavity, and then configure the cavity medium adjustment according to the specific medium. The type of medium can be obtained according to the use environment of the system control module. Generally, the medium is air, but it may also be a vacuum.

[0074] Step S30, obtaining interference frequency points of the PCB board according to the PCB board and components installed on the PCB board;

[0075] Interference frequency refers to the frequency of the point where electromagnetic oscillation is generated. The point where electromagnetic oscillation is generated in the circuit is related to the components and circuit layout of the circuit. The interference frequency of the PCB can be obtained based on the circuits on the PCB and the components installed on the PCB.

[0076] Specifically, step S30 includes:

[0077] Step S31, constructing an equivalent circuit model according to the PCB board and the components mounted on the PCB board;

[0078] Step S32, performing simulation calculation on the equivalent circuit model to obtain the interference frequency point of the PCB board.

[0079] According to the wiring on the PCB board, the working parameters and the parameters of the components installed on the PCB, an equivalent circuit model can be constructed. Then, the simulation software is used to simulate the equivalent circuit model to obtain the frequency of electromagnetic oscillations generated in the equivalent circuit and the corresponding interference frequency. These interference frequencies are the interference frequencies of the PCB board.

[0080] It should be noted that step S30 may also be executed before step S10 or simultaneously with step S10, and the execution order between step S30 and step S10 is not limited here.

[0081] Step S40, configuring electromagnetic boundary conditions of the cavity three-dimensional model;

[0082] The solution of electromagnetic field problems is attributed to the solution of Maxwell's equations. The differential form of Maxwell's equations is valid only under the premise that the field vector is single-valued, bounded and continuously distributed along the space. Boundary conditions are the characteristics of the electromagnetic field that define the boundary across the discontinuous boundary. According to the relationship between the simulation model and the surrounding space in reality, different boundary conditions can be set for each outer surface of the simulation model, such as ideal conductor boundary conditions, i.e., electric wall, ideal magnetic boundary conditions, i.e., magnetic wall, finite conductor boundary conditions, radiation boundary conditions, symmetric boundary conditions, impedance boundary conditions, lumped RLC boundary conditions, infinite ground plane, master-slave boundary conditions, ideal matching layers and layered impedance boundary conditions. In this embodiment, the outer surface of the cavity model is mainly set to an electric wall or a magnetic wall.

[0083] Specifically, step S40 includes:

[0084] Step S41, setting the surface in contact with the metal plate in the cavity three-dimensional model as a magnetic wall;

[0085] Step S42, setting the surface of the cavity three-dimensional model that is not in contact with the metal plate as an electrical wall.

[0086] Determine whether any outer surface of the cavity three-dimensional model is in contact with the metal plate. If the surface in the cavity three-dimensional model is in contact with the metal plate, set the surface in the cavity three-dimensional model as a magnetic wall, and the electric field vector of the magnetic wall is tangent to the model surface, and the magnetic field vector is perpendicular to the model surface; if the surface in the cavity three-dimensional model is not in contact with the metal plate, set the surface in the cavity three-dimensional model as an electric wall, and the electric field vector of the electric wall is perpendicular to the model surface, and the magnetic field vector is tangent to the model surface. In this way, corresponding boundary conditions are set for each outer surface in the cavity three-dimensional model. The boundary conditions set for each surface in the cavity three-dimensional model constitute the electromagnetic boundary conditions of the cavity three-dimensional model.

[0087] Step S50, performing simulation analysis on the cavity three-dimensional model according to the electromagnetic boundary conditions and the cavity medium conditions to obtain simulation results, wherein the simulation results include at least one eigenfrequency of the cavity;

[0088] After the electromagnetic boundary conditions and the intracavity medium conditions are configured for the cavity three-dimensional model, the cavity three-dimensional model can be simulated and analyzed according to the configured electromagnetic boundary conditions and intracavity medium conditions to obtain at least one eigenfrequency of the cavity.

[0089] For the simulation analysis process, specifically, step S50 includes:

[0090] Step S51, receiving the convergence condition, the number of iterations, the minimum solution frequency and the number of solution modes input by the user;

[0091] Step S52, performing eigenmode simulation analysis on the cavity three-dimensional model according to the electromagnetic boundary conditions, the cavity medium, the convergence condition, the number of iterations, the minimum solution frequency and the number of solution modes to obtain the simulation results.

[0092] After configuring the boundary conditions of the cavity 3D model, you need to input the parameters of the simulation process, including the convergence conditions, number of iterations, minimum solution frequency, and number of solution modes. The convergence conditions and number of iterations refer to the stop conditions for meshing the cavity 3D model. The minimum solution frequency refers to the minimum threshold of each eigenfrequency obtained by the simulation analysis. The number of solution modes refers to the number of eigenfrequencies obtained by the simulation analysis. After configuring the convergence conditions, number of iterations, minimum solution frequency, and number of solution modes, the simulation software will first perform adaptive meshing of the cavity 3D model according to the convergence conditions and number of iterations. Specifically, each time the meshing is performed, the mesh model will be calculated to obtain the parameter S 后 , according to the parameter S calculated by the previous grid model 前 A comparison is made and the error between the two is calculated. When the error reaches the convergence condition, the mesh division will be stopped. If the convergence condition is not reached, further mesh subdivision will be performed on the current mesh model until the convergence condition is reached or the number of divisions reaches the number of iterations, then the mesh division will be stopped.

[0093] When the grid division is completed, by configuring the cavity medium, the material properties of the cavity can be obtained through the mapping relationship between each material and the corresponding material properties pre-stored in the simulation software. For example, if the material of the cavity is configured as air, the relative dielectric constant and relative magnetic permeability corresponding to the air can be directly obtained. Then, according to the electromagnetic boundary conditions, the electromagnetic properties of the medium, the minimum solution frequency and the solution model, the eigenmode simulation analysis is performed on the final cavity grid model to finally obtain the simulation results, which include at least one eigenfrequency, the electric field distribution corresponding to the eigenfrequency and the magnetic field distribution corresponding to the eigenfrequency.

[0094] Step S60, determining whether there is an eigenfrequency of the cavity that is the same as the interference frequency; if so, executing step S61; if not, executing step S62;

[0095] Step S61, determining that the cavity will generate electromagnetic interference;

[0096] Step S62, determining that the cavity does not generate electromagnetic interference.

[0097] After obtaining the eigenfrequency of the cavity, the eigenfrequency of the cavity will be compared with the interference frequency point on the PCB board obtained previously to determine whether there is an eigenfrequency that is the same as the interference frequency point. If there is at least one eigenfrequency in the cavity that is the same as any interference frequency point on the PCB board, it will be determined that the cavity will generate electromagnetic interference due to resonance. If the eigenfrequencies of the cavity are different from any interference frequency point on the PCB board, it will be determined that the cavity will not resonate and thus generate electromagnetic interference.

[0098] In this embodiment, a cavity three-dimensional model in the system control module is obtained according to a structural model of the system control module, wherein the system control module includes at least one PCB board and at least one metal plate, and the cavity three-dimensional model is a three-dimensional model of a cavity formed between two relatively arranged PCB boards and / or a three-dimensional model of a cavity formed between a relatively arranged PCB board and a metal plate; an intracavity medium of the cavity is obtained, and an intracavity medium condition is configured according to the intracavity medium; an interference frequency point of the PCB board is obtained according to the PCB board and components mounted on the PCB board; an electromagnetic boundary condition of the cavity three-dimensional model is configured; a simulation analysis is performed on the cavity three-dimensional model according to the electromagnetic boundary condition and the intracavity medium condition to obtain a simulation result, wherein the simulation result includes at least one eigenfrequency of the cavity; and it is determined whether there is an eigenfrequency identical to the interference frequency point in the eigenfrequency of the cavity; if so, it is determined that the cavity will generate electromagnetic interference; if not, it is determined that the cavity will not generate electromagnetic interference. Therefore, during the structural design stage of the system control module, it is possible to predict whether the cavity in the designed system control module will generate electromagnetic interference. This prediction method is an ex ante prediction. Even if the prediction result is that electromagnetic interference will be generated, only the design model of the system control module needs to be adjusted, and no adjustment is required to the finished product, thereby reducing the number and cost of subsequent adjustments to the finished product and also reducing the unqualified rate of the finished product's electromagnetic interference performance.

[0099] Further, refer to Figure 3 According to the first embodiment of the electromagnetic interference prediction method of the present application, a second embodiment of the electromagnetic interference prediction method of the present application is proposed. In this embodiment, before step S40, the following steps are included:

[0100] Step S70, obtaining the size parameters of the cavity according to the three-dimensional model of the cavity;

[0101] Step S80, judging whether the size parameters of the cavity meet the preset size conditions according to the size parameters of the cavity, the interference frequency of the medium in the cavity and the PCB board; if yes, executing step S40.

[0102] The step S40 comprises:

[0103] Step S43, when the size parameters of the cavity meet the preset size conditions, the electromagnetic boundary conditions of the cavity three-dimensional model are configured.

[0104] The cavity formed between two PCBs arranged opposite to each other or between a PCB and a metal plate arranged opposite to each other does not necessarily have an eigenfrequency. It is possible to have an eigenfrequency only when the size parameters of the cavity meet the preset size conditions. Specifically, according to the acquired three-dimensional model of the cavity, the size parameters of the cavity can be obtained, and the size parameters include the size in the direction perpendicular to the PCB, i.e., the height, and the size in two directions parallel to the PCB and perpendicular to each other, i.e., the length and width. It is judged whether the ratio of the height to the length is less than the first preset threshold, whether the ratio of the height to the width is less than the second preset threshold, and whether the ratio of the height to the wavelength of the electromagnetic wave at the interference frequency in the medium of the cavity is less than the third preset threshold. If the three judgment results are all less than, it is determined that the size parameters of the cavity meet the preset size conditions, and the boundary conditions and subsequent simulations will be performed on the three-dimensional model of the cavity. If the result of at least one judgment condition is greater than or equal to, it is determined that the size parameters of the cavity do not meet the preset size conditions, and the cavity is excluded, and no simulation analysis is required for it.

[0105] It should be noted that, since there may be multiple interference frequencies on a PCB board, when there are multiple interference frequencies, when the results of the comparison of the height with the length and the width meet the conditions, it only needs the ratio of the height to the wavelength of the electromagnetic wave of one of the interference frequencies in the medium of the cavity to be less than the third preset threshold value, then it will be determined that the cavity size parameters meet the preset size conditions. Only when the ratio of the height to the wavelength of the electromagnetic waves of all interference frequencies in the medium of the cavity is greater than or equal to the third preset threshold value, will it be determined that the cavity size parameters do not meet the preset size conditions.

[0106] Before simulating the cavity, this embodiment first determines whether alignment is required for simulation based on the size of the cavity, so as to exclude cavities that do not meet the simulation conditions, reduce the workload of the entire prediction process, and improve efficiency.

[0107] Furthermore, the present invention also provides a method for eliminating electromagnetic interference, referring to Figure 4 According to a first embodiment of the electromagnetic interference elimination method of the present invention, the electromagnetic interference elimination method comprises the steps of:

[0108] Step S01, acquiring a three-dimensional model of a cavity in the system control module according to a structural model of the system control module, wherein the system control module includes at least one PCB board and at least one metal plate, and the three-dimensional model of the cavity is a three-dimensional model of a cavity formed between two relatively arranged PCB boards and / or a three-dimensional model of a cavity formed between a relatively arranged PCB board and a metal plate;

[0109] In this embodiment, the system control module refers to the core control module in the terminal, including at least one PCB board that plays a control role, and at least one metal plate that is assembled with the PCB board. For example, in a smart TV, the PCB board can be a movement board, a TCON board, or a power board, etc., and the metal plate can be a metal back plate of a TV or a metal heat sink mounted on the PCB board. The cavity formed between two PCB boards that are relatively arranged in the system control module, and the cavity formed between the PCB board and the metal plate that are relatively arranged. The structural model of the system control module can be a virtual three-dimensional structural model of a system control module that has been produced, or a virtual three-dimensional structural model of a system control module that has not been produced and is still in the design stage. According to the structural model of the system control module, the three-dimensional model of the cavity in the system control module can be obtained. The three-dimensional model of the cavity can be a three-dimensional model of the cavity formed between two PCB boards that are relatively arranged, and / or a three-dimensional model of the cavity formed between a PCB board that is relatively arranged and a metal plate. The process of the cavity three-dimensional model can be to extract the three-dimensional model of the cavity formed between the two relatively arranged PCB boards and / or the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate from the structural model of the constructed system control module by using the extraction technology in professional three-dimensional modeling software (such as Pro / E, CAD, UG, SolidWorks, etc.) or professional electromagnetic simulation software (such as HFSS, MICROWAVE STUDIO, Ansys Designer, etc.). It can also be to directly construct the three-dimensional model of the cavity formed between the two relatively arranged PCB boards in the system control module and / or the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate according to the design structure or actual structure of the system control module using the three-dimensional modeling function provided in professional three-dimensional modeling software (such as Pro / E, CAD, UG, SolidWorks, etc.) or professional electromagnetic simulation software (such as HFSS, MICROWAVE STUDIO, Ansys Designer, etc.), for example, using HFSS to directly construct the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate.

[0110] It should be noted that no matter the cavity 3D model is constructed directly in 3D modeling software or simulation software or the cavity 3D model is extracted through extraction technology, the surface of the obtained cavity 3D model may have some defects, such as surface mismatch, intersection and interference between surfaces, holes and gaps on the surface, etc. Before simulation, the surface needs to be preprocessed. According to the type of surface defects, the processing methods include manual repair, surface wrapping or surface reconstruction, and the preprocessed cavity 3D model is used as the simulation object.

[0111] Step S02, obtaining the intracavity medium of the cavity, and configuring the intracavity medium conditions according to the intracavity medium;

[0112] When performing electromagnetic field simulation, it is also necessary to configure the cavity medium conditions, that is, the material properties corresponding to the cavity three-dimensional model, such as relative magnetic permeability, relative dielectric constant, conductivity, dielectric loss tangent, magnetic loss tangent, relative magnetic permeability tensor, relative dielectric constant tensor, conductivity tensor, dielectric loss tangent tensor, magnetic loss tangent tensor and other parameters. These parameters are related to the medium in the cavity. Before simulating the cavity, you must first obtain the medium in the cavity, and then configure the cavity medium adjustment according to the specific medium. The type of medium can be obtained according to the use environment of the system control module. Generally, the medium is air, but it may also be a vacuum.

[0113] Step S03, obtaining interference frequency points of the PCB board according to the PCB board and components installed on the PCB board;

[0114] The interference frequency point refers to the frequency of the point where electromagnetic oscillation is generated. The point where electromagnetic oscillation is generated in the circuit is related to the circuit arrangement of the components and circuits in the circuit. The interference frequency point of the PCB can be obtained based on the circuits on the PCB board and the components installed on the PCB board. The detailed execution process of step S03 is the same as the detailed execution process of step S30 in the first embodiment of the aforementioned electromagnetic interference prediction method, and will not be repeated here.

[0115] It should be noted that step S03 may also be executed before step S01 or simultaneously with step S01, and the execution order between step S03 and step S01 is not limited here.

[0116] Step S04, configuring the electromagnetic boundary conditions of the cavity three-dimensional model;

[0117] The solution of electromagnetic field problems is attributed to the solution of Maxwell's equations. The differential form of Maxwell's equations is valid only under the premise that the field vector is single-valued, bounded and continuously distributed along the space. Boundary conditions are the characteristics of the electromagnetic field that defines the boundary across the discontinuous boundary. According to the relationship between the simulation model and the simulation model in practice and the surrounding space, different boundary conditions can be set for each outer surface of the simulation model, such as ideal conductor boundary conditions, i.e., electric wall, ideal magnetic boundary conditions, i.e., magnetic wall, finite conductor boundary conditions, radiation boundary conditions, symmetric boundary conditions, impedance boundary conditions, lumped RLC boundary conditions, infinite ground plane, master-slave boundary conditions, ideal matching layers, and layered impedance boundary conditions. In this embodiment, the outer surface of the cavity model is mainly set to an electric wall or a magnetic wall. The detailed execution process of step S04 is the same as the detailed execution process of step S40 in the first embodiment of the aforementioned electromagnetic interference prediction method, and will not be repeated here.

[0118] It should be noted that the cavity formed between two PCBs arranged opposite to each other or between a PCB and a metal plate arranged opposite to each other does not necessarily have an eigenfrequency. It is possible to have an eigenfrequency only when the size parameters of the cavity meet the preset size conditions. Specifically, according to the obtained three-dimensional model of the cavity, the size parameters of the cavity can be obtained, and the size parameters include the size in the direction perpendicular to the PCB, i.e., the height, and the size in two directions parallel to the PCB and perpendicular to each other, i.e., the length and width. It is judged whether the ratio of the height to the length is less than the first preset threshold, whether the ratio of the height to the width is less than the second preset threshold, and whether the ratio of the height to the wavelength of the electromagnetic wave at the interference frequency in the medium of the cavity is less than the third preset threshold. If the three judgment results are all less than, it is determined that the size parameters of the cavity meet the preset size conditions, and the boundary conditions and subsequent simulations will be performed on the three-dimensional model of the cavity. If the result of at least one judgment condition is greater than or equal to, it is determined that the size parameters of the cavity do not meet the preset size conditions, and the cavity is excluded, and no simulation analysis is required for it.

[0119] Since there may be multiple interference frequencies on a PCB board, when there are multiple interference frequencies, under the condition that the results of the comparison of the height with the length and the width all meet the conditions, it is only necessary that the ratio of the height to the wavelength of the electromagnetic wave of one of the interference frequencies in the medium of the cavity is less than the third preset threshold value, then it will be determined that the cavity size parameters meet the preset size conditions. Only when the ratio of the height to the wavelength of the electromagnetic waves of all the interference frequencies in the medium of the cavity is greater than or equal to the third preset threshold value, will it be determined that the cavity size parameters do not meet the preset size conditions.

[0120] Step S05, performing simulation analysis on the cavity three-dimensional model according to the electromagnetic boundary conditions and the cavity medium conditions to obtain simulation results, wherein the simulation results include at least one eigenfrequency of the cavity;

[0121] After the electromagnetic boundary conditions and the medium conditions in the cavity are configured for the three-dimensional model of the cavity, the three-dimensional model of the cavity can be simulated and analyzed according to the configured electromagnetic boundary conditions and the medium conditions in the cavity to obtain at least one eigenfrequency of the cavity. The detailed execution process of step S05 is the same as the detailed execution process of step S50 in the first embodiment of the aforementioned electromagnetic interference prediction method, and will not be repeated here.

[0122] Step S06, determining whether there is an eigenfrequency in the cavity that is the same as the interference frequency;

[0123] After obtaining the eigenfrequency of the cavity, the eigenfrequency of the cavity will be compared with the interference frequency point on the PCB board obtained previously to determine whether there is an eigenfrequency that is the same as the interference frequency point. If there is at least one eigenfrequency in the cavity that is the same as any interference frequency point on the PCB board, it will be determined that the cavity will generate electromagnetic interference due to resonance. If the eigenfrequencies of the cavity are different from any interference frequency point on the PCB board, it will be determined that the cavity will not resonate and thus generate electromagnetic interference.

[0124] Step S07, when there is an eigenfrequency in the cavity that is the same as the interference frequency, adjust the structural model of the system control module and return to step S01 until it is determined that the cavity will not generate electromagnetic interference.

[0125] If the cavity in the structural model of the designed system control module is determined to generate electromagnetic radiation, the structural model of the system control module will be adjusted. The structural model of the system control module can be adjusted by adjusting the size parameters of the PCB board, the distance between the PCB board and the metal plate, the size parameters of the metal plate, and setting metal connectors at one or more locations in the cavity. If the cavity in the structural model of the designed system control module is determined to not generate electromagnetic radiation, the designed system control module will not be adjusted, but the design structural model of the system control module will be used as the basis for producing the finished product.

[0126] Specifically, step S07 includes:

[0127] Step S071, adjusting at least one of the size parameters of the PCB board in the system control module, adjusting the distance between the PCB board and the metal plate relatively set in the system control module, adjusting the distance between two PCB boards relatively set in the system control module, and adjusting the size parameters of the metal plate in the system control module.

[0128] Since the eigenfrequency of the cavity is related to the cavity, the dimensional parameters of the cavity can be changed by changing any one of the dimensional parameters of the PCB board forming the cavity, the distance between the relatively set PCB board and the metal plate forming the cavity, the distance between the two relatively set PCB boards forming the cavity, and the dimensional parameters of the metal plate forming the cavity in the structural model of the system control module, thereby ultimately changing the eigenfrequency of the cavity.

[0129] Specifically, step S07 further includes:

[0130] Step S072, according to the intracavity electric field distribution corresponding to the eigenfrequency that is the same as the interference frequency point, taking the position corresponding to the maximum electric field strength value in the intracavity electric field distribution as the short-circuit point position;

[0131] Step S073, adding a three-dimensional model corresponding to a metal connector at the short-circuit point position, wherein the metal connector is used to connect an oppositely disposed PCB board and a metal plate or to connect two oppositely disposed PCB boards.

[0132] Due to some reasons, the adjustment of the size of the PCB board, the size of the metal plate, the spacing between the relatively set PCB board and the metal plate, and the spacing between the relatively set PCB boards is limited. For example, for a PCB board that has already been produced, it is impossible to adjust the size of the PCB board, or adjusting the size of the PCB board will lead to an increase in the cost of the subsequently produced PCB boards. In the case where the adjustment of the size of the PCB board, the size of the metal plate, the spacing between the relatively set PCB board and the metal plate, and the spacing between the relatively set PCB boards is limited, the structural model of the adjustment system control module can also be adjusted to set a metal connector as a short-circuit point in the cavity formed by the PCB board and the metal plate or the cavity formed between the PCB board and the PCB board, connecting the PCB board and the metal plate or connecting the PCB board and the PCB board, resulting in a change in the three-dimensional model of the cavity and simultaneously changing the electromagnetic boundary conditions of the three-dimensional model of the cavity, thereby changing the eigenfrequency of the cavity. The specific process of adding a three-dimensional model of a metal connector is as follows: in addition to the eigenfrequency, the simulation results also include the electric field distribution corresponding to the eigenfrequency, obtain the intra-cavity electric field distribution corresponding to the eigenfrequency that is the same as the interference frequency, and use the position corresponding to the maximum electric field strength value in the intra-cavity electric field distribution as the short-circuit point position, and then add a three-dimensional model of the metal connector at the short-circuit point. The three-dimensional model of the metal connector can be pre-built or directly generated when it needs to be added.

[0133] It should be noted that when there are components at the position corresponding to the maximum electric field strength value or the position is not suitable for installing a metal connector, a position closest to the position where a metal connector can be installed will be selected as a short-circuit point.

[0134] Each time the structural model of the system control module is adjusted, the three-dimensional model of the cavity is re-acquired according to the adjusted structural model of the system control module, the boundary conditions of the three-dimensional model of the cavity are reconfigured, the interference frequency is re-acquired, the three-dimensional model of the cavity is simulated again to obtain the simulation result of the cavity, and it is judged again whether the cavity still generates electromagnetic radiation based on the simulation result. If it still generates, the above steps are repeated until it is determined that the cavity does not generate electromagnetic interference, that is, the cavity no longer generates electromagnetic radiation. When it is determined that the cavity no longer generates electromagnetic radiation, the PCB board and the metal plate are produced according to the current structural model of the system control module, or the system control module that has been produced is adjusted.

[0135] This embodiment obtains the simulation results of electromagnetic interference through a simulation method, determines whether adjustment is needed according to the simulation results, verifies the adjustment plan of the virtual model when adjustment is needed, determines the final adjustment plan, guides production or adjusts the finished products that have been produced according to the final adjustment plan, which can reduce the actual number of adjustments and adjustment costs, and can also reduce the electromagnetic interference unqualified rate of the finished products produced.

[0136] The present invention also proposes a system control module production method, referring to Figure 5 According to a first embodiment of the system control module production method of the present invention, the system control module production method comprises the steps of:

[0137] Step S100, acquiring a three-dimensional model of a cavity in the system control module according to an initial structural model of the system control module, wherein the three-dimensional model of the cavity is a three-dimensional model of a cavity formed between two PCB boards arranged opposite to each other and / or a three-dimensional model of a cavity formed between a PCB board and a metal plate arranged opposite to each other;

[0138] In this embodiment, the system control module refers to the core control module in the terminal, including at least one PCB board that plays a control role, and at least one metal plate that is assembled with the PCB board. For example, in a smart TV, the PCB board can be a movement board, a TCON board, or a power board, etc., and the metal plate can be a metal back plate of the TV or a metal heat sink installed on the PCB board. The cavity refers to the cavity between two adjacent PCB boards in the system control module and / or the cavity between two adjacent PCB boards and the metal plate. The structural model of the system control module in this embodiment is a virtual three-dimensional structural model of the system control module in the design stage. According to the structural model of the system control module, the three-dimensional model of the cavity in the system control module can be obtained. The three-dimensional model of the cavity can be a three-dimensional model of the cavity formed between two relatively arranged PCB boards, and / or a three-dimensional model of the cavity formed between a relatively arranged PCB board and a metal plate. The process of building the three-dimensional model of the cavity can be to use extraction technology in professional three-dimensional modeling software (such as Pro / E, CAD, UG, SolidWorks, etc.) or professional electromagnetic simulation software (such as HFSS, MICROWAVE STUDIO, Ansys Designer, etc.) to extract the three-dimensional model of the cavity formed between the two relatively arranged PCB boards and / or the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate from the structural model of the constructed system control module. It can also be to use the three-dimensional modeling function provided in professional three-dimensional modeling software (such as Pro / E, CAD, UG, SolidWorks, etc.) or professional electromagnetic simulation software (such as HFSS, MICROWAVE STUDIO, Ansys Designer, etc.) to directly build the three-dimensional model of the cavity formed between the two relatively arranged PCB boards in the system control module and / or the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate, for example, using HFSS to directly build the three-dimensional model of the cavity formed between the relatively arranged PCB board and the metal plate.

[0139] It should be noted that no matter the cavity 3D model is constructed directly in 3D modeling software or simulation software or the cavity 3D model is extracted through extraction technology, the surface of the obtained cavity 3D model may have some defects, such as surface mismatch, intersection and interference between surfaces, holes and gaps on the surface, etc. Before simulation, the surface needs to be preprocessed. According to the type of surface defects, the processing methods include manual repair, surface wrapping or surface reconstruction, and the preprocessed cavity 3D model is used as the simulation object.

[0140] Step S200, obtaining the intracavity medium of the cavity, and configuring the intracavity medium condition according to the intracavity medium;

[0141] When performing electromagnetic field simulation, it is also necessary to configure the cavity medium conditions, that is, the material properties corresponding to the cavity three-dimensional model, such as relative magnetic permeability, relative dielectric constant, conductivity, dielectric loss tangent, magnetic loss tangent, relative magnetic permeability tensor, relative dielectric constant tensor, conductivity tensor, dielectric loss tangent tensor, magnetic loss tangent tensor and other parameters. These parameters are related to the medium in the cavity. Before simulating the cavity, you must first obtain the medium in the cavity, and then configure the cavity medium adjustment according to the specific medium. The type of medium can be obtained according to the use environment of the system control module. Generally, the medium is air, but it may also be a vacuum.

[0142] Step S300, obtaining interference frequency points of the PCB board according to the PCB board and components installed on the PCB board;

[0143] The interference frequency point refers to the frequency of the point where electromagnetic oscillation is generated. The point where electromagnetic oscillation is generated in the circuit is related to the components and circuit layout of the circuit. The interference frequency point of the PCB can be obtained based on the circuits on the PCB board and the components installed on the PCB board. The detailed execution process of step S300 is the same as the detailed execution process of step S30 in the first embodiment of the aforementioned electromagnetic interference prediction method, and will not be repeated here.

[0144] It should be noted that step S300 may also be executed before step S100 or simultaneously with step S100, and the execution order between step S300 and step S100 is not limited here.

[0145] Step S400, configuring electromagnetic boundary conditions of the cavity three-dimensional model;

[0146] The solution of electromagnetic field problems is attributed to the solution of Maxwell's equations. The differential form of Maxwell's equations is valid only under the premise that the field vector is single-valued, bounded and continuously distributed along the space. Boundary conditions are the characteristics of the electromagnetic field that defines the boundary across the discontinuous boundary. According to the relationship between the simulation model and the surrounding space in reality, different boundary conditions can be set for each outer surface of the simulation model, such as ideal conductor boundary conditions, i.e., electric wall, ideal magnetic boundary conditions, i.e., magnetic wall, finite conductor boundary conditions, radiation boundary conditions, symmetric boundary conditions, impedance boundary conditions, lumped RLC boundary conditions, infinite ground plane, master-slave boundary conditions, ideal matching layer and layered impedance boundary conditions. In this embodiment, the outer surface of the cavity model is mainly set to an electric wall or a magnetic wall. The detailed execution process of step S400 is the same as the detailed execution process of step S40 in the first embodiment of the aforementioned electromagnetic interference prediction method, and will not be repeated here.

[0147] It should be noted that the cavity formed between two PCBs arranged opposite to each other or between a PCB and a metal plate arranged opposite to each other does not necessarily have an eigenfrequency. It is possible to have an eigenfrequency only when the size parameters of the cavity meet the preset size conditions. Specifically, according to the obtained three-dimensional model of the cavity, the size parameters of the cavity can be obtained, and the size parameters include the size in the direction perpendicular to the PCB, i.e., the height, and the size in two directions parallel to the PCB and perpendicular to each other, i.e., the length and width. It is judged whether the ratio of the height to the length is less than the first preset threshold, whether the ratio of the height to the width is less than the second preset threshold, and whether the ratio of the height to the wavelength of the electromagnetic wave at the interference frequency in the medium of the cavity is less than the third preset threshold. If the three judgment results are all less than, it is determined that the size parameters of the cavity meet the preset size conditions, and the boundary conditions and subsequent simulations will be performed on the three-dimensional model of the cavity. If the result of at least one judgment condition is greater than or equal to, it is determined that the size parameters of the cavity do not meet the preset size conditions, and the cavity is excluded, and no simulation analysis is required for it.

[0148] Since there may be multiple interference frequencies on a PCB board, when there are multiple interference frequencies, under the condition that the results of the comparison of the height with the length and the width all meet the conditions, it is only necessary that the ratio of the height to the wavelength of the electromagnetic wave of one of the interference frequencies in the medium of the cavity is less than the third preset threshold value, then it will be determined that the cavity size parameters meet the preset size conditions. Only when the ratio of the height to the wavelength of the electromagnetic waves of all the interference frequencies in the medium of the cavity is greater than or equal to the third preset threshold value, will it be determined that the cavity size parameters do not meet the preset size conditions.

[0149] Step S500, performing simulation analysis on the cavity three-dimensional model according to the electromagnetic boundary conditions and the cavity medium conditions to obtain simulation results, wherein the simulation results include at least one eigenfrequency of the cavity;

[0150] After the electromagnetic boundary conditions and the medium conditions in the cavity are configured for the three-dimensional model of the cavity, the three-dimensional model of the cavity can be simulated and analyzed according to the configured electromagnetic boundary conditions and the medium conditions in the cavity to obtain at least one eigenfrequency of the cavity. The detailed execution process of step S500 is the same as the detailed execution process of step S50 in the first embodiment of the aforementioned electromagnetic interference prediction method, and will not be repeated here.

[0151] Step S600, determining whether there is an eigenfrequency of the cavity that is the same as the interference frequency; if not, executing step S700; if yes, executing step S800;

[0152] After obtaining the eigenfrequency of the cavity, the eigenfrequency of the cavity will be compared with the interference frequency point on the PCB board obtained previously to determine whether there is an eigenfrequency that is the same as the interference frequency point. If there is at least one eigenfrequency in the cavity that is the same as any interference frequency point on the PCB board, it will be determined that the cavity will generate electromagnetic interference due to resonance. If the eigenfrequencies of the cavity are different from any interference frequency point on the PCB board, it will be determined that the cavity will not resonate and thus generate electromagnetic interference.

[0153] Step S700, producing a system control module according to the structural model of the system control module;

[0154] When it is determined that the cavity in the structural model of the initially designed system control module does not generate electromagnetic radiation, the PCB board and metal plate in the system control module will be produced directly according to the structural model of the initially designed system control module and assembled to form the system control module.

[0155] Step S800, adjusting the structural model of the system control module, and returning to step S100, until it is determined that the cavity in the adjusted structural model of the system control module does not generate electromagnetic interference;

[0156] Step S900 , producing a system control module according to the structure model of the system control module adjusted to correspond to the cavity not generating electromagnetic interference.

[0157] When it is determined that the cavity in the structural model of the designed system control module will generate electromagnetic radiation, the structural model of the system control module will be adjusted. The structural model of the system control module can be adjusted by at least one of adjusting the size parameters of the PCB board, adjusting the distance between the relatively arranged PCB board and the metal plate, adjusting the distance between two relatively arranged PCB boards, adjusting the size parameters of the metal plate, and setting metal connectors at one or more locations in the cavity. The specific adjustment process is the same as the specific adjustment process involved in the first embodiment of the aforementioned electromagnetic interference elimination method, and will not be repeated here.

[0158] Each time the structural model of the system control module is adjusted, the three-dimensional model of the cavity is re-acquired according to the adjusted structural model of the system control module, the boundary conditions of the three-dimensional model of the cavity are reconfigured, the interference frequency is re-acquired, the three-dimensional model of the cavity is simulated again to obtain the simulation result of the cavity, and it is judged again whether the cavity still generates electromagnetic radiation according to the simulation result. If it still generates electromagnetic radiation, the above steps are repeated until it is determined that the cavity in the structural model of the adjusted system control module does not generate electromagnetic interference, that is, the cavity no longer generates electromagnetic radiation. When it is determined that the cavity no longer generates electromagnetic radiation, the PCB board and the metal plate are produced according to the current adjusted structural model of the system control module, and assembled to form the system control module.

[0159] This embodiment obtains the simulation results of electromagnetic interference through a simulation method, determines whether adjustment is needed according to the simulation results, verifies the adjustment plan of the virtual model when adjustment is needed, determines the final adjustment plan, and produces finished products according to the final adjustment plan, which can reduce the electromagnetic interference unqualified rate of the finished products and save production costs.

[0160] The present invention also provides a computer-readable storage medium on which a computer program is stored. The computer-readable storage medium may be Figure 1 The memory 20 in the terminal may also be at least one of a ROM (Read-Only Memory) / RAM (Random Access Memory), a magnetic disk, and an optical disk. The computer-readable storage medium includes some information for enabling the intelligent terminal to execute the methods described in each embodiment of the electromagnetic interference prediction method and the electromagnetic interference elimination method in the present invention.

[0161] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0162] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0163] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method.

[0164] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for predicting electromagnetic interference, characterized in that: Includes steps: According to the structural model of the system control module, a three-dimensional model of the cavity in the system control module is obtained, wherein the system control module includes at least one PCB board and at least one metal plate, and the three-dimensional model of the cavity is a three-dimensional model of the cavity formed between two relatively arranged PCB boards and / or a three-dimensional model of the cavity formed between a relatively arranged PCB board and a metal plate; Acquire the intracavitary medium of the cavity, and configure the intracavitary medium condition according to the intracavitary medium; Obtain the interference frequency of the PCB board according to the PCB board and the components installed on the PCB board; Configure electromagnetic boundary conditions for the 3D model of the cavity; According to the electromagnetic boundary conditions and the medium conditions in the cavity, a three-dimensional model of the cavity is simulated and analyzed to obtain a simulation result, wherein the simulation result includes at least one eigenfrequency of the cavity; Determine whether there is an eigenfrequency in the cavity that is the same as the interference frequency; If it exists, it is determined that the cavity will generate electromagnetic interference; If not present, it is determined that the cavity will not generate electromagnetic interference.

2. The electromagnetic interference prediction method according to claim 1, characterized in that: The step of configuring the electromagnetic boundary conditions of the cavity three-dimensional model comprises: The surface in contact with the metal plate in the three-dimensional model of the cavity is set as a magnetic wall; The surfaces in the cavity 3D model that are not in contact with the metal plate are set as electrical walls.

3. The electromagnetic interference prediction method according to claim 2, characterized in that: The step of obtaining the interference frequency of the PCB board according to the PCB board and the components installed on the PCB board comprises: Construct an equivalent circuit model based on the PCB board and the components installed on the PCB board; The equivalent circuit model is simulated and calculated to obtain the interference frequency point of the PCB board.

4. The electromagnetic interference prediction method according to claim 3, characterized in that: The step of configuring the electromagnetic boundary conditions of the cavity three-dimensional model also includes: According to the three-dimensional model of the cavity, the size parameters of the cavity are obtained; According to the size parameters of the cavity, the interference frequency of the medium in the cavity and the PCB board, it is judged whether the size parameters of the cavity meet the preset size conditions; The step of configuring the electromagnetic boundary conditions of the cavity three-dimensional model comprises: When the size parameters of the cavity meet the preset size conditions, the electromagnetic boundary conditions of the cavity three-dimensional model are configured.

5. The electromagnetic interference prediction method according to claim 4, characterized in that: The steps of simulating and analyzing the cavity three-dimensional model according to the electromagnetic boundary conditions and the cavity medium to obtain the simulation results are as follows: Receive the convergence condition, the number of iterations, the minimum solution frequency and the number of modes to be solved input by the user; According to the electromagnetic boundary conditions, the medium in the cavity, the convergence conditions, the number of iterations, the minimum solution frequency and the number of solution modes, the eigenmode simulation analysis of the cavity three-dimensional model is carried out to obtain the simulation results.

6. A method for eliminating electromagnetic interference, characterized in that: Includes steps: According to the structural model of the system control module, a three-dimensional model of the cavity in the system control module is obtained, wherein the system control module includes at least one PCB board and at least one metal plate, and the three-dimensional model of the cavity is a three-dimensional model of the cavity formed between two relatively arranged PCB boards and / or a three-dimensional model of the cavity formed between a relatively arranged PCB board and a metal plate; Acquire the intracavitary medium of the cavity, and configure the intracavitary medium condition according to the intracavitary medium; Obtain the interference frequency of the PCB board according to the PCB board and the components installed on the PCB board; Configure electromagnetic boundary conditions for the 3D model of the cavity; According to the electromagnetic boundary conditions and the medium conditions in the cavity, a three-dimensional model of the cavity is simulated and analyzed to obtain a simulation result, wherein the simulation result includes at least one eigenfrequency of the cavity; Determine whether there is an eigenfrequency in the cavity that is the same as the interference frequency; When there is an eigenfrequency in the cavity that is the same as the interference frequency, adjust the structural model of the system control module and return to execute: the structural model of the system control module, and obtain the three-dimensional model of the cavity in the system control module until it is determined that the cavity will not generate electromagnetic interference.

7. The electromagnetic interference elimination method according to claim 6, characterized in that: The step of adjusting the structural model of the system control module comprises: At least one of adjusting the size parameters of the PCB board in the system control module, adjusting the distance between the PCB board and the metal plate relatively set in the system control module, adjusting the distance between two PCB boards relatively set in the system control module, and adjusting the size parameters of the metal plate in the system control module.

8. The electromagnetic interference elimination method according to claim 7, characterized in that: The simulation result also includes the electric field distribution in the cavity corresponding to the eigenfrequency. The step of adjusting the structural model of the system control module includes: According to the intracavity electric field distribution corresponding to the eigenfrequency which is the same as the interference frequency point, the position corresponding to the maximum electric field strength value in the intracavity electric field distribution is taken as the short-circuit point position; A three-dimensional model corresponding to a metal connector is added at the short-circuit point, where the metal connector is used to connect a PCB board and a metal plate that are relatively arranged, or to connect two PCB boards that are relatively arranged.

9. A terminal, characterized in that: The terminal includes: a communication module, a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, the steps of the electromagnetic interference prediction method according to any one of claims 1 to 5 and / or the steps of the electromagnetic interference elimination method according to any one of claims 6 to 8 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the electromagnetic interference prediction method according to any one of claims 1 to 5 and / or the steps of the electromagnetic interference elimination method according to any one of claims 6 to 8.

11. A method for producing a system control module, characterized in that: The system control module includes at least one PCB board and at least one metal plate; the system control module production method includes the steps of: According to the structural model of the system control module, a three-dimensional model of the cavity in the system control module is obtained, wherein the three-dimensional model of the cavity is a three-dimensional model of the cavity formed between two PCB boards arranged opposite to each other and / or a three-dimensional model of the cavity formed between a PCB board and a metal plate arranged opposite to each other; Acquire the intracavitary medium of the cavity, and configure the intracavitary medium condition according to the intracavitary medium; Obtain the interference frequency of the PCB board according to the PCB board and the components installed on the PCB board; Configure electromagnetic boundary conditions for the 3D model of the cavity; According to the electromagnetic boundary conditions and the medium conditions in the cavity, a three-dimensional model of the cavity is simulated and analyzed to obtain a simulation result, wherein the simulation result includes at least one eigenfrequency of the cavity; Determine whether there is an eigenfrequency in the cavity that is the same as the interference frequency; If it does not exist, the system control module is produced according to the structural model of the system control module; If it exists, the structural model of the system control module is adjusted, and the step of obtaining the three-dimensional model of the cavity in the system control module according to the structural model of the system control module is returned to be executed until it is determined that the cavity in the adjusted structural model of the system control module will not generate electromagnetic interference; A system control module is produced according to the structural model of the system control module adjusted to correspond to the cavity not generating electromagnetic interference.

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