Preparation method of charging pile circuit board and charging pile circuit board

Abstract

The invention provides a preparation method of a charging pile circuit board and the charging pile circuit board. The method comprises the following steps: obtaining a to-be-embedded copper block required by a charging pile circuit board; embedding the copper block to be embedded into a core plate to obtain the core plate with the copper block; laminating the copper foil, the cured sheet and the core plate with the copper block to obtain a laminated plate; performing circuit manufacturing on the laminated plate to obtain a first charging pile circuit board; obtaining a heat parameter of the first charging pile circuit board under a heat simulation model; inputting the heat parameter into a preset heat dissipation evaluation model for evaluating the heat dissipation effect of the circuit board to obtain an evaluation result; according to the evaluation result, manufacturing parameters of a target charging pile circuit board are determined; and obtaining the target charging pile circuit board according to the manufacturing parameters of the target charging pile circuit board, the target to-be-embedded copper block, the target core board, the target copper foil and the target cured sheet. The heat dissipation performance of the charging pile circuit board can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit boards, and also to a method for preparing a charging pile circuit board and a charging pile circuit board. Background Art

[0002] In recent years, with many advantages such as environmental protection, energy saving, and high efficiency, new energy electric vehicles have become the first choice when purchasing vehicles. Charging piles are an important logistical part to ensure the convenience and smooth travel of new energy vehicles. The main control board is the core component of the new energy vehicle charging pile. As the electronic carrier of the core component, the circuit board requires high insulation, high current resistance, heat dissipation, and high wear resistance. Therefore, the circuit board for charging piles is generally buried / embedded heat dissipation copper blocks and ultra-thick copper to meet performance requirements, but this will cause the circuit board manufacturing process to be difficult, the process to be long, and the heat dissipation performance to be unstable. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for preparing a charging pile circuit board and a charging pile circuit board, so as to improve the heat dissipation performance and production efficiency of the charging pile circuit board.

[0004] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0005] A first aspect of the present invention provides a method for preparing a charging pile circuit board, comprising:

[0006] Obtain the copper blocks to be embedded in the charging pile circuit board;

[0007] Embedding the copper block to be embedded into the core board to obtain a core board with the copper block;

[0008] Pressing the copper foil, the cured sheet and the core board with the copper block to obtain a pressed board;

[0009] Performing circuit fabrication on the pressed plate to obtain a first charging pile circuit board;

[0010] Obtaining thermal parameters of the first charging pile circuit board under a thermal simulation model;

[0011] Inputting the thermal parameters into a preset heat dissipation evaluation model to evaluate the heat dissipation effect of the circuit board to obtain an evaluation result;

[0012] Determine the manufacturing parameters of the target charging pile circuit board according to the evaluation results;

[0013] The target charging pile circuit board is obtained according to the manufacturing parameters of the target charging pile circuit board and the target copper block to be embedded, the target core board, the target copper foil and the target cured sheet.

[0014] Optionally, embedding the copper block to be embedded into the core board to obtain the core board with the copper block comprises:

[0015] Embedding the copper block to be embedded into the core board according to preset embedding parameters to obtain a core board with the copper block;

[0016] The copper foil, the cured sheet and the core board with the copper block are pressed together to obtain a pressed board, comprising:

[0017] The copper foil, the curing sheet and the core board with the copper block are pressed together according to a preset stacking sequence to obtain a pressed board.

[0018] Optionally, obtaining thermal parameters of the first charging pile circuit board under a thermal simulation model includes:

[0019] Obtaining preset simulation parameters of the first charging pile circuit board under a thermal simulation model;

[0020] The first charging pile circuit board is subjected to heat dissipation simulation processing according to the preset simulation parameters to obtain heat parameters.

[0021] Optionally, the preset simulation parameters include:

[0022] Temperature parameter: the temperature parameter is 20 to 30°C;

[0023] Convective heat transfer coefficient; the convection heat transfer coefficient is 5 to 10 ;

[0024] Radiation heat transfer parameters; the radiation heat transfer parameters are We get: where Q is the radiation heat transfer parameter, is the emissivity of the first charging pile circuit board, is a constant, A is the surface area of ​​the first charging pile circuit board, is the total energy density radiated to the environment by the first charging pile circuit board, is the total energy density radiated from the environment to the first charging pile circuit board;

[0025] Thermal conductivity of copper block;

[0026] Specifications of copper blocks;

[0027] Position parameters of the copper block;

[0028] Thermal conductivity of the first charging pile circuit board;

[0029] Power supply input power; the power supply input power is obtained by P=VI, where P is the power supply input power, V is the voltage, and I is the current.

[0030] Optionally, the heat parameters are input into a preset heat dissipation evaluation model to evaluate the heat dissipation effect of the circuit board to obtain an evaluation result, including:

[0031] Inputting the thermal parameters into a first sub-model of a preset heat dissipation evaluation model to obtain thermal resistance;

[0032] Inputting the heat parameter into a second sub-model of a preset heat dissipation evaluation model to obtain heat dissipation efficiency;

[0033] Inputting the thermal resistance and the heat dissipation efficiency into a third sub-model of a preset heat dissipation evaluation model to obtain a heat dissipation performance index;

[0034] An evaluation result is obtained according to the heat dissipation performance index and a preset evaluation level.

[0035] Optionally, according to the evaluation result, determining the manufacturing parameters of the target charging pile circuit board includes:

[0036] Obtain preset parameter adjustment standards;

[0037] According to the evaluation result and the preset parameter adjustment standard, the manufacturing parameters of the target charging pile circuit board are determined.

[0038] Optionally, determining the manufacturing parameters of the target charging pile circuit board according to the evaluation result and the preset parameter adjustment standard includes:

[0039] When the evaluation result is lower than a preset expected level, adjusting the first production parameter according to the preset parameter adjustment standard to obtain a second production parameter;

[0040] According to the second production parameters, the manufacturing parameters of the target charging pile circuit board are determined.

[0041] Optionally, the method further includes:

[0042] Testing the target charging pile circuit board to obtain a target test result;

[0043] The target charging pile circuit board is screened according to the test results and preset qualification conditions to obtain a qualified charging pile circuit board.

[0044] Optionally, testing the target charging pile circuit board to obtain a target test result includes:

[0045] Performing a thermal shock test on the target charging pile circuit board to obtain a first test result;

[0046] Performing a high temperature placement test on the target charging pile circuit board to obtain a second test result;

[0047] Performing a moisture placement test on the target charging pile circuit board to obtain a third test result;

[0048] Performing a thermal shock test on the target charging pile circuit board to obtain a fourth test result;

[0049] Performing a heat dissipation performance test on the target charging pile circuit board to obtain a fifth test result;

[0050] A target test result is obtained according to the first test result, the second test result, the third test result, the fourth test result and the fifth test result.

[0051] A second aspect of the present invention provides a charging pile circuit board, wherein the charging pile circuit board is prepared by the method for preparing the charging pile circuit board as described in the first aspect.

[0052] The above solution of the present invention includes at least the following beneficial effects:

[0053] The above scheme of the present invention embeds the copper blocks to be embedded required for the charging pile circuit board into the core board to obtain a core board with copper blocks, and then presses the copper foil, the curing sheet and the core board with the copper blocks to obtain a pressed board, and then performs circuit manufacturing on the pressed board to obtain a first charging pile circuit board as a sample for heat dissipation simulation processing and circuit board heat dissipation effect evaluation, determines the manufacturing parameters of the target charging pile circuit board according to the evaluation results, and finally manufactures the target charging pile circuit board according to the manufacturing parameters of the target charging pile circuit board and the target copper blocks to be embedded, the target core board, the target copper foil and the target curing sheet, which is not only beneficial to improving the heat dissipation performance of the charging pile circuit board, but also can improve the production efficiency and qualified rate of the charging pile circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a schematic diagram of the process of the method for preparing the charging pile circuit board in an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0056] like Figure 1 As shown, an embodiment of the present invention provides a method for preparing a charging pile circuit board, comprising the following steps:

[0057] Step 101, obtaining the copper blocks to be embedded in the charging pile circuit board;

[0058] Step 102, embedding the copper block to be embedded into the core board to obtain a core board with the copper block;

[0059] Step 103, pressing the copper foil, the cured sheet and the core board with the copper block to obtain a pressed board;

[0060] Step 104, performing circuit fabrication on the pressed plate to obtain a first charging pile circuit board;

[0061] Step 105, obtaining thermal parameters of the first charging pile circuit board under a thermal simulation model;

[0062] Step 106, inputting the heat parameters into a preset heat dissipation evaluation model to evaluate the heat dissipation effect of the circuit board to obtain an evaluation result;

[0063] Step 107, determining the manufacturing parameters of the target charging pile circuit board according to the evaluation result;

[0064] Step 108, obtaining the target charging pile circuit board according to the manufacturing parameters of the target charging pile circuit board and the target copper block to be embedded, the target core board, the target copper foil and the target cured sheet.

[0065] The preparation method of the charging pile circuit board proposed in the embodiment of the present invention embeds the copper block to be embedded required for the charging pile circuit board into a core board to obtain a core board with a copper block, and then presses the copper foil, a curing sheet and the core board with the copper block to obtain a pressed board, and then performs circuit manufacturing on the pressed board to obtain a first charging pile circuit board as a sample for heat dissipation simulation processing and circuit board heat dissipation effect evaluation, and determines the manufacturing parameters of the target charging pile circuit board according to the evaluation results, and finally manufactures the target charging pile circuit board according to the manufacturing parameters of the target charging pile circuit board and the target copper block to be embedded, the target core board, the target copper foil and the target curing sheet, which is not only beneficial to improving the heat dissipation performance of the charging pile circuit board, but also can improve the production efficiency and qualified rate of the charging pile circuit board.

[0066] In an optional embodiment of the present invention, step 101 includes:

[0067] Step 1011, obtaining the copper blocks to be embedded required for the charging pile circuit board;

[0068] Specifically, the copper block has a thickness of at least 2.0 mm.

[0069] Step 1012, obtaining the core board required for the charging pile circuit board;

[0070] Specifically, there may be multiple core plates, and the thickness of the core plates is 2.0 mm or 3.5 mm, and the material is a glass fiber reinforced epoxy resin matrix or a ceramic matrix.

[0071] Step 1013, obtaining the copper foil required for the charging pile circuit board;

[0072] Specifically, the number of copper foils may be multiple, and the weight of the copper foil may be 9.0 OZ (ounces).

[0073] Step 1014, obtaining the cured sheet required for the charging pile circuit board;

[0074] Specifically, the number of the cured sheets may be multiple, and the cured sheet is 7628PP (a semi-cured sheet, the ingredients of which include epoxy resin, curing agent and glass fiber cloth, and the specifications include a weight of 208±5 grams per square meter).

[0075] Step 1015, obtaining the first production parameter.

[0076] Specifically, the first production parameters include copper block production parameters and circuit board production parameters, wherein the copper block production parameters may include the length, width, position, shape, etc. of the copper block, and the circuit board production parameters may include the embedding position of the copper block, line width, line spacing, number of layers, surface treatment methods (such as tin spraying, gold plating, organic solderability film or copper protection agent, etc.). It should be noted that the first production parameters may also include various parameters or data required to prepare the first charging pile circuit board, such as preset embedding parameters and preset stacking sequence. The purpose of obtaining the first production parameters is to facilitate the subsequent production of the first charging pile circuit board according to the parameters as a sample for heat dissipation performance evaluation, so as to improve the production parameters and improve the heat dissipation performance of the final prepared charging pile circuit board.

[0077] In actual application, specific first production parameters can be set according to the actual application scenario, and copper blocks, core boards, copper foils, cured sheets, etc. of suitable materials or specifications can be obtained, so as to facilitate the subsequent preparation of the first charging pile circuit board according to the first production parameters and related materials.

[0078] In an optional embodiment of the present invention, step 102 includes:

[0079] The copper block to be embedded is embedded into the core board according to preset embedding parameters to obtain a core board with the copper block.

[0080] Specifically, the embedding process may include: cutting the copper block to be embedded to obtain a cut copper block, wherein the length, width and shape of the cut copper block are consistent with the length, width and shape of the copper block in the first production parameter; pre-treating the cut copper block (such as micro-etching and browning) to obtain a pre-treated copper block, wherein the purpose of the pre-treatment is to improve the corrosion resistance and oxidation resistance of the copper block, remove scratches and stains on the surface of the copper block, improve the flatness of the surface of the copper block, and increase the firmness of the connection between the copper block and the core board; milling a copper embedding groove in the copper embedding area of ​​the core board to obtain a core board with a groove, wherein the length, width, depth, shape and height of the copper embedding groove need to be adapted to the length, width, thickness and shape of the pre-treated copper block to ensure that the copper block can be tightly embedded therein; browning the core board to improve the bonding force between the core board and the copper block; placing the pre-treated copper block in the core board with a groove to obtain a core board with a copper block. Here, the preset embedding parameters may include:

[0081] The micro-etching processing parameters for micro-etching the copper block include: the micro-etching liquid composition is pure water or distilled water, dilute ammonia water and hydrogen peroxide, wherein the volume ratio of ammonia water is generally 3% to 10% (about 300cc), and the amount of hydrogen peroxide added is 2 to 3 drops; the micro-etching processing time is 1 to 3 seconds.

[0082] The parameters for the browning treatment of the copper block include: the composition of the browning liquid contains sulfuric acid, hydrogen peroxide and a specific browning agent (such as a mixture of sulfuric acid and nitric acid); the temperature of the browning tank is 35±2°C; the mass fraction of sulfuric acid is 4% to 6%, and the mass fraction of hydrogen peroxide is 4% to 6%; the treatment rate (micro-etching rate) is 50 to 80 micro-inches / second (u″ / s).

[0083] In an optional embodiment of the present invention, step 103 includes:

[0084] The copper foil, the curing sheet and the core board with the copper block are pressed together according to a preset stacking sequence to obtain a pressed board.

[0085] Specifically, a specific preset lamination sequence (need to meet the number of layers in the first production parameter) can be: copper foil, 2 cured sheets, core board with copper block, 2 cured sheets, copper foil; according to the preset lamination sequence, the core board with copper block, copper foil and cured sheet are stacked together, and then riveted, and then pressed according to the pressing parameters of pressing temperature of 100 to 175°C, pressure of 400 to 750PSI (pounds per square inch), time including heating time of 30 minutes to 2 hours, heat preservation time of 20 minutes to 1 hour, and cooling time of 1 hour to 4 hours, to obtain a pressed board. In actual production, the above preset lamination sequence and pressing parameters can be adjusted according to actual conditions. The above is only a specific description of one embodiment.

[0086] Before lamination, the copper foil can be treated as follows:

[0087] The top and bottom layers of the copper foil are both 9.0OZ. A CNC drilling machine and a 2.0mm drill are used to drill positioning holes at the preset positions of the copper foil to obtain copper foil with positioning holes for subsequent stacking alignment and fixation to ensure that the layers will not be misaligned during the lamination process; according to the preset graphics, the top and bottom layer graphic transfer negatives are made, and the negatives are used to block the parts that do not need to be etched during the exposure process to ensure the accuracy and clarity of the graphic transfer negatives to avoid unnecessary defects during the etching process; the prepared graphic transfer negatives are attached to the copper foil with positioning holes and exposed using an exposure device. After exposure, the parts not blocked by the negatives will be exposed to ultraviolet rays. The exposed copper foil is placed in an acid etching solution for etching. The etching solution will selectively remove the parts of the copper foil that are not exposed to ultraviolet rays to form the desired graphic circuit; after the acid etching is completed, the positive side of the top layer and the negative side of the bottom layer are back-etched. Back etching is a process of removing excess metal layers on the surface of the copper foil by chemical or physical methods, which can improve the accuracy and flatness of the circuit and obtain a copper foil with graphic circuits.

[0088] Here, a specific embodiment of obtaining a pressed board by pressing process includes:

[0089] Use cutting equipment to cut the copper block to be embedded to obtain the cut copper block, and the cut copper block meets the length, width, thickness (such as 2.0mm) and shape of the copper block in the first production parameter; use a CNC drilling machine and a 2.0mm drill bit to drill a positioning hole at the preset drilling position of the copper block; brown the copper block with the positioning hole drilled to form a dense oxide film on the copper surface to enhance the bonding force between the copper and the core board; clean the copper block after browning to remove debris, oil and other impurities to ensure that the surface of the copper block is clean and free of defects; use cutting equipment to cut the FR-4 board into the required size (meeting the length, width, thickness and shape of the core board in the first production parameter) to obtain the core board, wherein the thickness of the core board is 2.0mm, and FR-4 is a glass fiber reinforced epoxy resin laminate with good electrical properties and mechanical properties. Strength; Use a CNC drilling machine to drill 3.2mm diameter positioning holes at the first preset position of the core. These positioning holes are used for subsequent stacking alignment and fixation to ensure that the layers will not be misaligned during the lamination process; Use a gong machine or milling machine to gong the required slots at the second preset position of the core board (in line with the copper block embedding position in the first production parameter). The slots are used to embed copper blocks to improve the heat dissipation performance of the circuit board; Use an ultrasonic cleaner or other cleaning equipment to remove debris and stains generated during drilling and gong grooving to ensure that the surface of the board is clean and free of oil, dust and other impurities. After cleaning, use compressed air or dust-free cloth to further clean the surface; Stack the core board, prepreg and copper block in the preset stacking order to ensure that the layers are accurately aligned and the positioning holes and slots correspond correctly; Put the stacked boards into the laminating machine for heating and pressurization to obtain a pressed board.

[0090] In specific implementation, the thickness of the core board can also be 3.5 mm, using 3 curing sheets, which can be set according to user needs.

[0091] In an optional embodiment of the present invention, step 104 includes:

[0092] The circuit of the pressed plate is fabricated according to the first production parameters to obtain a first charging pile circuit board.

[0093] Specifically, a circuit pattern is produced on a laminated board according to the line width and spacing in the first production parameter, a layer of photosensitive film is affixed to the copper foil surface of the laminated board so that an expected circuit pattern can be formed through subsequent exposure and development steps, a conductive circuit pattern is made through exposure and development, a copper layer is plated on the conductive circuit pattern to increase the thickness of the copper layer, and the copper layer in the non-retained area of ​​the semi-finished board after the additional plating is etched away using an alkaline solution to retain a conductive circuit pattern that meets the expected requirements, thereby obtaining the first charging pile circuit board.

[0094] After the lamination process, the edge of the lamination plate is trimmed to remove uneven parts such as burrs and overflowed glue. An ultrasonic cleaner or other cleaning equipment is used to thoroughly remove oil, dust and other impurities on the surface of the lamination plate to ensure that the surface is clean and provide a good working environment for subsequent circuit production; a positive or negative film with a circuit pattern is attached to the lamination plate and exposed, and a developer is used to remove the part of the pattern transfer material that is not exposed to ultraviolet rays, and then an etching process is performed to remove the remaining pattern transfer material, clean the surface of the lamination plate, remove the residues generated during the etching and film stripping process, and apply solder mask ink on the surface of the circuit to protect the circuit from environmental corrosion and mechanical damage to obtain the first charging pile circuit board.

[0095] It should be noted that the above step numbers are only for exemplary purposes. In the actual production process, the above steps can be adjusted, such as first making circuits on the core board, then embedding copper blocks and pressing them together, or first making circuits on the inner layer of the core board and the copper foil, then embedding copper blocks and pressing them together.

[0096] In an optional embodiment of the present invention, step 105 includes:

[0097] Step 1051, obtaining preset simulation parameters of the first charging pile circuit board under the thermal simulation model;

[0098] Specifically, the preset simulation parameters may include set boundary conditions and related parameters, which may be determined based on the actual working environment of the charging pile circuit board and the specifications of the charging pile.

[0099] Step 1052: Perform heat dissipation simulation processing on the first charging pile circuit board according to the preset simulation parameters to obtain heat parameters.

[0100] Specifically, the first charging pile circuit board can be modeled and simulated using circuit simulation software or thermal simulation software, preset simulation parameters can be input, and thermal parameters can be output through simulation. Thermal parameters can include temperature difference (difference between heat source temperature and ambient temperature), heat dissipation power, heat dissipated by the heat dissipation system, and heat generated by the first charging pile circuit board.

[0101] In an optional embodiment of the present invention, the preset simulation parameters in step 1051 include:

[0102] Temperature parameter; the temperature parameter is 20 to 30°C; specifically, the temperature parameter can be determined according to the working environment of the charging pile. If the charging pile is installed indoors, the ambient temperature can be set between 20°C and 30°C; if the charging pile is installed outdoors, the appropriate temperature range can be set according to the actual geographical location and historical temperature.

[0103] Convective heat transfer coefficient; the convection heat transfer coefficient is 5 to 10 Here, the convective heat transfer coefficient can be calculated by h=f(flow rate, fluid properties, object shape, etc.), where h is the convective heat transfer coefficient, which reflects the heat transfer capacity between the fluid and the solid surface. The fluid properties (such as air or water or oil or other coolants) include the density, viscosity, specific heat capacity and thermal conductivity of the fluid, etc. The object shape refers to the shape of the charging pile circuit board, including its length, width, thickness, and surface geometric features (such as fins, grooves, etc.).

[0104] Radiation heat transfer parameters; the radiation heat transfer parameters are We get: where Q is the radiation heat transfer parameter, is the emissivity of the first charging pile circuit board, is a constant, A is the surface area of ​​the first charging pile circuit board, T is the absolute temperature of the surface of the first charging pile circuit board, It is the fourth power of T, representing the total energy density radiated by the first charging pile circuit board to the environment. is the absolute temperature of the environment The fourth power represents the total energy density radiated from the environment to the first charging pile circuit board;

[0105] Thermal conductivity of copper block; generally between 380 and 400 W / (m·K);

[0106] Specifications of the copper block; such as length, width, thickness and shape;

[0107] Copper block location parameters; the location of the copper block in the circuit board, such as near the heat source or the area where heat is concentrated.

[0108] The thermal conductivity of the first charging pile circuit board is generally between 0.1 and 2 W / (m·K);

[0109] Power input power: The power input power is obtained by P=VI, where P is the power input power, V is the voltage, and I is the current. The power input power depends on the specifications of the charging pile and the load requirements. For example, a charging pile may have multiple charging modules, and the input power of each module may be different.

[0110] Specifically, the preset simulation parameters mentioned above can be selected according to specific needs, so as to simulate the first charging pile circuit board according to the preset simulation parameters to obtain thermal parameters. The thermal parameters may include the temperature difference between the first charging pile circuit board and the ambient temperature when the first charging pile circuit board works normally in the charging pile system, the heat dissipation power, the heat dissipated by the heat dissipation system, and the heat generated by the first charging pile circuit board, wherein the heat dissipated by the heat dissipation system is usually equal to the heat dissipation power, but if there are multiple heat dissipation paths on the first charging pile circuit board (such as natural heat dissipation, fan heat dissipation, liquid cooling, etc.), it is necessary to calculate the heat dissipated by each heat dissipation path separately, and sum them up to obtain the total heat dissipation; the heat generated by the first charging pile circuit board is the total heat generated by the first charging pile circuit board, which can be obtained by multiplying the heat generation rate of the first charging pile circuit board by the simulation time, wherein the heat generation rate of the entire first charging pile circuit board can be obtained by the power consumption of each component on the first charging pile circuit board and the corresponding heat generation rate.

[0111] In an optional embodiment of the present invention, step 106 includes:

[0112] Step 1061, inputting the thermal parameters into a first sub-model of a preset heat dissipation evaluation model to obtain thermal resistance;

[0113] Specifically, the first sub-model includes , where R is the thermal resistance, is the temperature difference (the difference between the heat source temperature and the ambient temperature), and P is the heat dissipation power.

[0114] Step 1062, inputting the heat parameter into a second sub-model of a preset heat dissipation evaluation model to obtain heat dissipation efficiency;

[0115] Specifically, the second sub-model includes , where n is the heat dissipation efficiency, To dissipate the heat of the cooling system, The heat generated by the first charging pile circuit board.

[0116] Step 1063, inputting the thermal resistance and the heat dissipation efficiency into a third sub-model of a preset heat dissipation evaluation model to obtain a heat dissipation performance index;

[0117] Specifically, the third sub-model includes , where S is the heat dissipation performance index, R is the thermal resistance, and n is the heat dissipation efficiency.

[0118] Step 1064, obtaining an evaluation result according to the heat dissipation performance index and a preset evaluation level.

[0119] Specifically, the smaller the heat dissipation performance index is, the better the heat dissipation performance is. The preset evaluation level may include the value of the heat dissipation performance index and its corresponding level, such as S is 1, the corresponding level is excellent, S is 5, the corresponding level is good, S is 10, the corresponding level is poor. The evaluation result may include the value of the heat dissipation performance index and the corresponding evaluation level.

[0120] In an optional embodiment of the present invention, step 107 includes:

[0121] Step 1071, obtaining a preset parameter adjustment standard;

[0122] Specifically, the preset parameter adjustment standards include:

[0123] Minimize thermal resistance by reducing the thermal resistance of the circuit board and its components to promote more efficient heat transfer from the heat source to the heat dissipation medium. This can be achieved by at least one of the following methods: increasing the volume of the copper block, placing it close to the heat source, increasing the contact area between the copper block and the core board, selecting a copper block or heat sink with a high thermal conductivity, or increasing the heat dissipation area.

[0124] Maximize heat dissipation efficiency to increase the ratio of heat dissipated by the heat dissipation system to the heat generated by the circuit board. This can be achieved by any of the following methods: optimize the heat dissipation structure, such as using heat dissipation pipes or heat dissipation covers; improve convection heat transfer conditions, such as adding fans or increasing coolant flow; use radiation heat transfer, such as increasing thermal radiation by coating high-emissivity materials; increase the surface area of ​​the copper block (such as adding fins), increase the line width / spacing, reduce local hot spots, and force convection to enhance heat dissipation capabilities.

[0125] Step 1072, determining the manufacturing parameters of the target charging pile circuit board according to the evaluation result and the preset parameter adjustment standard.

[0126] In an optional embodiment of the present invention, step 1072 includes:

[0127] Step 10721, when the evaluation result is lower than the preset expected level, adjusting the first production parameter according to the preset parameter adjustment standard to obtain the second production parameter;

[0128] Specifically, if the evaluation result does not meet the preset expected level (such as good or excellent), the copper block production parameters and circuit board production parameters in the first production parameters need to be adjusted according to the preset parameter adjustment standards to obtain the copper block production parameters and circuit board production parameters that minimize thermal resistance and maximize heat dissipation efficiency as the second production parameters for the production of the target charging pile circuit board.

[0129] In a specific embodiment, the first production parameter and the second production parameter are shown in Table 1:

[0130] Table 1 The first production parameters and the second production parameters

[0131] parameter First production parameter Second production parameter Adjustment purpose Copper block volume 20 30 Expand heat dissipation area Copper block location 5mm from heat dissipation components (such as transistors) Fits to the bottom of heat dissipation components (such as transistors) Shorten the heat conduction path and reduce contact thermal resistance Line width 1.5mm 2.5mm Increase current carrying capacity and reduce Joule heating Line spacing 0.5mm 1mm Reduce electromagnetic interference and thermal coupling with adjacent lines, and reduce local temperature rise Cooling method Natural convection Forced convection Improve the convection heat transfer coefficient

[0132] By adjusting the first production parameter in the above manner to obtain the second production parameter, the temperature difference between the target charging pile circuit board and the surrounding environment can be reduced, the thermal resistance of the target charging pile circuit board can be reduced, the temperature of the copper block surface can be reduced, and the heat dissipation efficiency of the target charging pile circuit board can be improved.

[0133] Step 10722: Determine the manufacturing parameters of the target charging pile circuit board based on the second production parameters.

[0134] Specifically, the manufacturing parameters of the target charging pile circuit board include second production parameters.

[0135] In an optional embodiment of the present invention, step 108 includes:

[0136] Step 1081, obtaining a target copper block to be embedded, a target core board, a target copper foil and a target cured sheet according to the manufacturing parameters of the target charging pile circuit board;

[0137] Specifically, the provided raw materials can be cut and manufactured according to the manufacturing parameters of the target charging pile circuit board to obtain the target copper block to be embedded, the target core board, the target copper foil and the target cured sheet that meet the manufacturing parameters.

[0138] Step 1082, obtaining the target charging pile circuit board according to the manufacturing parameters of the target charging pile circuit board and the target copper block to be embedded, the target core board, the target copper foil and the target cured sheet.

[0139] Specifically, according to the preparation process or process of the charging pile circuit board, according to the production parameters of the target charging pile circuit board and the target copper block to be embedded, the target core board, the target copper foil and the target cured sheet, the target charging pile circuit board can be prepared.

[0140] In a specific embodiment, the process of preparing the target charging pile circuit board includes:

[0141] Embed a 2.0 mm thick copper block into a preset slot of a 2.0 mm thick core board;

[0142] Stack the materials in the following preset stacking order starting from the top layer: TL side (top layer): 9.0OZ (about 0.3mm) copper foil; 7628PP (prepreg): 2 sheets; 2.0mm FR-4 core board with embedded copper blocks; 7628 PP: 2 sheets; BL side (bottom layer): 9.0OZ copper foil;

[0143] Use riveting equipment or technology to ensure that each layer of material is accurately aligned and fixed at the alignment holes; put the stacked materials into a press, heat and pressurize them to obtain a pressed board;

[0144] Target holes are punched into the press plate for subsequent alignment and positioning; these target holes help ensure accuracy and consistency during subsequent processing.

[0145] A photosensitive resist layer is coated on the surface of the copper foil on the laminate; during the exposure process, the resist layer will form the required circuit pattern according to the selective shielding of the pattern transfer material.

[0146] Use an etching process to remove the copper foil portion that is not blocked by the photosensitive resist layer to form the required circuit pattern and obtain an initial charging pile circuit board;

[0147] Performing a gold treatment on the initial charging pile circuit board to obtain a second charging pile circuit board; to improve the welding performance and corrosion resistance of the circuit; the gold treatment layer may include a thin layer of nickel and a thin layer of gold;

[0148] Countersunk holes are drilled on the second charging pile circuit board to obtain a third charging pile circuit board; these holes can be used to install components or make other mechanical connections. Among them, the countersunk holes can include through holes, plug-in holes (for inserting electronic components), and binding holes (for fixing or binding circuit boards). In addition, the hole walls of these openings can be copper-plated to form a copper layer on the hole walls through chemical reactions, or copper ions can be reduced to copper on the hole walls under the action of an external current by electroplating copper, which can enhance the connection strength between the hole walls and subsequent conductive circuits and ensure good electrical conductivity.

[0149] The third charging pile circuit board is formed using mechanical or laser cutting equipment to meet the length, width and shape requirements in the production parameters.

[0150] In an optional embodiment of the present invention, the method further comprises:

[0151] Step 109, testing the target charging pile circuit board to obtain a target test result;

[0152] Specifically, according to actual needs, multiple types of tests can be performed on the target charging pile circuit board, and each test result constitutes a target test result, so that qualified charging pile circuit boards can be screened out according to the target test result to improve product quality.

[0153] Step 1010, screening the target charging pile circuit board according to the test result and preset qualification conditions to obtain a qualified charging pile circuit board.

[0154] Specifically, the target charging pile circuit boards whose test results meet the preset qualified conditions are packaged and sent to customers as qualified charging pile circuit boards to improve product quality and customer satisfaction. Here, the preset qualified conditions may include: no bubbles, delamination; no cracks, bursting, falling off, etc.

[0155] In an optional embodiment of the present invention, step 109 includes:

[0156] Step 1091, performing a thermal shock test on the target charging pile circuit board to obtain a first test result;

[0157] Specifically, when performing a hot and cold shock test, the target charging pile circuit board can be placed in a -40°C cold temperature tank, shock for 30 minutes, then at room temperature for 5 minutes, then at 125°C for 30 minutes, then at room temperature for 5 minutes, one cycle in sequence, for a total of 100 cycles. The first test result can include the process of the hot and cold shock test and the appearance and performance (such as changes in resistance, capacitance, inductance and other parameters) of the target charging pile circuit board after the hot and cold shock test.

[0158] Step 1092, performing a high temperature placement test on the target charging pile circuit board to obtain a second test result;

[0159] Specifically, when performing the high temperature placement test, the target charging pile circuit board can be placed in an oven at 100 to 110°C for 120 hours. The second test result can include the process of the high temperature placement test and the appearance and performance (such as changes in resistance, capacitance, inductance and other parameters) of the target charging pile circuit board after the high temperature placement test.

[0160] Step 1093, performing a moisture placement test on the target charging pile circuit board to obtain a third test result;

[0161] Specifically, when performing the moisture placement test, the target charging pile circuit board can be placed in a constant temperature humidity oven at a temperature of 60 to 65°C and a humidity of 90 to 95°C for 120 hours. The third test result may include the process of the moisture placement test and the appearance and performance (such as changes in parameters such as resistance, capacitance, and inductance) of the target charging pile circuit board after the moisture placement test.

[0162] Step 1094, performing a thermal shock test on the target charging pile circuit board to obtain a fourth test result;

[0163] Specifically, when performing a thermal shock test, the target charging pile circuit board can be placed in a thermal shock test box and subjected to a thermal shock of 288°C, 10 seconds each time, and 3 times. The fourth test result may include the process of the thermal shock test and the appearance and performance (such as changes in parameters such as resistance, capacitance, and inductance) of the target charging pile circuit board after the thermal shock test.

[0164] Step 1095, performing a heat dissipation performance test on the target charging pile circuit board to obtain a fifth test result;

[0165] Specifically, when conducting a heat dissipation performance test, the target charging pile circuit board can be placed in a heat dissipation performance test system and the temperature sensor can be connected. After turning on the heat dissipation performance test system, the load condition of the target charging pile circuit board in actual use can be simulated, and its temperature changes can be monitored. The temperature distribution, heat dissipation efficiency and possible overheating of the target charging pile circuit board under different load conditions are recorded as the fifth test result.

[0166] Specifically, an insulation resistance test can also be performed on the target charging pile circuit board to obtain a sixth test result; a preset test voltage, usually a DC voltage, is applied to the target charging pile circuit board through an insulation resistance tester, and the insulation resistance tester measures the insulation resistance value on the target charging pile circuit board. The insulation resistance value reflects the insulation performance of the target charging pile circuit board surface and internal insulation layer. The measured insulation resistance value is recorded as the sixth test result.

[0167] Step 1096, obtaining a target test result according to the first test result, the second test result, the third test result, the fourth test result and the fifth test result.

[0168] Specifically, the target test result may include all contents of the first test result, the second test result, the third test result, the fourth test result, the fifth test result, and the sixth test result.

[0169] A specific embodiment of the method for preparing the charging pile circuit board of the embodiment of the present invention includes:

[0170] Step 111, obtaining the copper block, core board, copper foil, curing sheet and first production parameters required for preparing the first charging pile circuit board;

[0171] Step 112, cutting the copper block and embedding it into the slot of the core board to obtain a core board with the copper block;

[0172] Step 113, stacking the copper foil, the cured sheet and the core board with the copper block together according to a preset stacking sequence, and then riveting and pressing them to obtain a pressed board;

[0173] Step 114, performing circuit fabrication on the laminate by exposure, development and etching to obtain a first charging pile circuit board, and the first charging pile circuit board is used as a sample for subsequent heat dissipation performance evaluation, and then for subsequent batch production, which can save production costs and improve the heat dissipation efficiency of the circuit board;

[0174] Step 115, using circuit board simulation software, performing heat dissipation simulation processing on the first charging pile circuit board according to preset simulation parameters to obtain thermal parameters, the thermal parameters including temperature difference, heat dissipation power, heat dissipated by the heat dissipation system and heat generated by the first charging pile circuit board, etc. These thermal parameters are used for subsequent evaluation of the heat dissipation effect of the circuit board;

[0175] Step 116, inputting the heat parameters into a plurality of sub-models in a preset heat dissipation evaluation model, calculating a heat dissipation performance index, and obtaining an evaluation result of the first charging pile circuit board according to the heat dissipation performance index and a preset evaluation level;

[0176] Step 117, if the evaluation result does not reach the preset expected level, the copper block production parameter and the circuit board production parameter in the first production parameter need to be adjusted according to the preset parameter adjustment standard to obtain the second production parameter (i.e., manufacturing parameter) so as to minimize the thermal resistance of the circuit board and maximize the heat dissipation efficiency;

[0177] Step 118, cutting and manufacturing the provided raw materials (such as copper blocks, copper foils, core boards, etc.) according to the manufacturing parameters of the target charging pile circuit board, obtaining the target copper blocks to be embedded, the target core boards, the target copper foils and the target cured sheets that meet the manufacturing parameters, and preparing the target charging pile circuit board based on these materials.

[0178] The preparation method of the charging pile circuit board proposed in the embodiment of the present invention evaluates the heat dissipation performance of the first charging pile circuit board, and then adjusts the relevant production parameters so that the heat dissipation performance of the charging pile circuit board finally obtained meets the expected requirements, which is beneficial to improving the heat dissipation performance and product quality of the charging pile circuit board.

[0179] An embodiment of the present invention further provides a charging pile circuit board, and the charging pile circuit board is prepared by using the charging pile circuit board preparation method as described in any one of the above embodiments.

[0180] The charging pile circuit board of the embodiment of the present invention is prepared using the charging pile circuit board preparation method as described in any one of the above embodiments, has higher heat dissipation performance, and is more adaptable to the use scenarios of the charging pile.

[0181] It should be noted that in the apparatus and method of the present invention, it is obvious that each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent solutions of the present invention. In addition, the steps of performing the above series of processes can naturally be performed in chronological order according to the order of description, but do not necessarily need to be performed in chronological order. Some steps can be performed in parallel, crosswise or independently of each other.

[0182] It should be noted that, in the above-mentioned embodiments, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "include one..." do not exclude the existence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the implementation of the above-mentioned embodiments is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0183] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a charging pile circuit board, characterized in that: include: Obtain the copper blocks to be embedded in the charging pile circuit board; Embedding the copper block to be embedded into the core board to obtain a core board with the copper block; Pressing the copper foil, the cured sheet and the core board with the copper block to obtain a pressed board; Performing circuit fabrication on the pressed plate to obtain a first charging pile circuit board; Obtaining thermal parameters of the first charging pile circuit board under a thermal simulation model; Inputting the thermal parameters into a preset heat dissipation evaluation model to evaluate the heat dissipation effect of the circuit board to obtain an evaluation result; Determine the manufacturing parameters of the target charging pile circuit board according to the evaluation results; The target charging pile circuit board is obtained according to the manufacturing parameters of the target charging pile circuit board and the target copper block to be embedded, the target core board, the target copper foil and the target cured sheet.

2. The method for preparing a charging pile circuit board according to claim 1, characterized in that: Embedding the copper block to be embedded into the core board to obtain the core board with the copper block comprises: Embedding the copper block to be embedded into the core board according to preset embedding parameters to obtain a core board with the copper block; The copper foil, the cured sheet and the core board with the copper block are pressed together to obtain a pressed board, comprising: The copper foil, the curing sheet and the core board with the copper block are pressed together according to a preset stacking sequence to obtain a pressed board.

3. The method for preparing a charging pile circuit board according to claim 1, characterized in that: Obtaining thermal parameters of the first charging pile circuit board under a thermal simulation model includes: Obtaining preset simulation parameters of the first charging pile circuit board under a thermal simulation model; The first charging pile circuit board is subjected to heat dissipation simulation processing according to the preset simulation parameters to obtain heat parameters.

4. The method for preparing a charging pile circuit board according to claim 3, characterized in that: The preset simulation parameters include: Temperature parameter: the temperature parameter is 20 to 30°C; Convective heat transfer coefficient; the convection heat transfer coefficient is 5 to 10 ; Radiation heat transfer parameters; the radiation heat transfer parameters are We get: where Q is the radiation heat transfer parameter, is the emissivity of the first charging pile circuit board, is a constant, A is the surface area of ​​the first charging pile circuit board, is the total energy density radiated to the environment by the first charging pile circuit board, is the total energy density radiated from the environment to the first charging pile circuit board; Thermal conductivity of copper block; Specifications of copper blocks; Position parameters of the copper block; Thermal conductivity of the first charging pile circuit board; Power supply input power; the power supply input power is obtained by P=VI, where P is the power supply input power, V is the voltage, and I is the current.

5. The method for preparing a charging pile circuit board according to claim 1, characterized in that: The heat parameters are input into a preset heat dissipation evaluation model to evaluate the heat dissipation effect of the circuit board, and an evaluation result is obtained, including: Inputting the thermal parameters into a first sub-model of a preset heat dissipation evaluation model to obtain thermal resistance; Inputting the heat parameter into a second sub-model of a preset heat dissipation evaluation model to obtain heat dissipation efficiency; Inputting the thermal resistance and the heat dissipation efficiency into a third sub-model of a preset heat dissipation evaluation model to obtain a heat dissipation performance index; An evaluation result is obtained according to the heat dissipation performance index and a preset evaluation level.

6. The method for preparing a charging pile circuit board according to claim 1, characterized in that: According to the evaluation results, the manufacturing parameters of the target charging pile circuit board are determined, including: Obtain preset parameter adjustment standards; According to the evaluation result and the preset parameter adjustment standard, the manufacturing parameters of the target charging pile circuit board are determined.

7. The method for preparing a charging pile circuit board according to claim 6, characterized in that: According to the evaluation result and the preset parameter adjustment standard, the manufacturing parameters of the target charging pile circuit board are determined, including: When the evaluation result is lower than a preset expected level, adjusting the first production parameter according to the preset parameter adjustment standard to obtain a second production parameter; According to the second production parameters, the manufacturing parameters of the target charging pile circuit board are determined.

8. The method for preparing a charging pile circuit board according to claim 1, characterized in that: Also includes: Testing the target charging pile circuit board to obtain a target test result; The target charging pile circuit board is screened according to the test results and preset qualification conditions to obtain a qualified charging pile circuit board.

9. The method for preparing a charging pile circuit board according to claim 8, characterized in that: The target charging pile circuit board is tested to obtain a target test result, including: Performing a thermal shock test on the target charging pile circuit board to obtain a first test result; Performing a high temperature placement test on the target charging pile circuit board to obtain a second test result; Performing a moisture placement test on the target charging pile circuit board to obtain a third test result; Performing a thermal shock test on the target charging pile circuit board to obtain a fourth test result; Performing a heat dissipation performance test on the target charging pile circuit board to obtain a fifth test result; A target test result is obtained according to the first test result, the second test result, the third test result, the fourth test result and the fifth test result.

10. A charging pile circuit board, characterized in that: The charging pile circuit board is prepared by the method for preparing a charging pile circuit board according to any one of claims 1 to 9.

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