A frequency converter structure design method based on thermal simulation and frequency converter structure

Abstract

The disclosed embodiment relates to the field of frequency converters, and provides a frequency converter structure design method and frequency converter structure based on thermal simulation, wherein the frequency converter structure design method based on thermal simulation includes: establishing a frequency converter model, the frequency converter model includes a shell model, a capacitor model and a reactance model, the shell model includes a receiving cavity; the shell model also includes a boss; the shell model also includes a heat sink; the capacitor model and the reactance model are located in the receiving cavity; the shell model also includes a heat sink, and the heat sink extends from the top surface of the frequency converter model toward the receiving cavity; wherein the capacitor model includes: an internal winding core, a shell, a sealing layer, a pole and a top cover; performing thermal simulation processing on the frequency converter model, and adjusting at least one heat dissipation parameter of the frequency converter based on the result of the thermal simulation processing, the heat dissipation parameter includes: at least one of the size of the heat sink, the model of the heat dissipation device or the extension depth of the boss toward the receiving cavity. The accuracy of thermal simulation can be improved.

Description

Technical Field

[0001] The disclosed embodiments relate to the field of frequency converters, and in particular to a frequency converter structure design method based on thermal simulation and a frequency converter structure. Background Art

[0002] The inverter relies on the internal insulated gate bipolar transistor to open and close, adjust the voltage and frequency of the output power supply, and provide the required power supply voltage according to the actual needs of the motor, thereby achieving the purpose of energy saving and speed regulation. With the continuous improvement of industrial automation, inverters have been more and more widely used.

[0003] As the degree of systematization and integration of automation applications in various industries increases, customers' experience requirements are also getting higher and higher. The simple use, bulky size and appearance of inverters in the past can no longer meet customer needs. Inverters are rapidly moving towards integration, miniaturization and aesthetics. However, integration and miniaturization have brought challenges to the heat dissipation control of inverters, especially the heat dissipation of heat-sensitive devices such as capacitors. How to balance miniaturization and heat dissipation performance has become a topic that needs to be studied urgently. Summary of the invention

[0004] The disclosed embodiments provide a frequency converter structure design method and frequency converter structure based on thermal simulation, which can at least improve the accuracy of thermal simulation, thereby facilitating the design of a frequency converter structure that takes both miniaturization and heat dissipation performance into consideration.

[0005] According to some embodiments of the present disclosure, on the one hand, an inverter structure design method based on thermal simulation is provided in the embodiments of the present disclosure, including establishing an inverter model, wherein the inverter model includes a shell model, a capacitor model and a reactance model, wherein the shell model includes a housing cavity; the shell model also includes a boss, and the boss extends from the bottom surface of the shell model toward the housing cavity; the shell model also includes a heat sink, and the heat sink faces the housing cavity; the capacitor model and the reactance model are located in the housing cavity, the capacitor model is located above the reactance model, and the reactance model is directly opposite to the boss; the shell model also includes a heat sink, The heat sink extends from the top surface of the inverter model toward the accommodating cavity; wherein the capacitor model includes: an internal winding core, an outer shell, a sealing layer, a pole and a top cover, the outer shell surrounds the internal winding core, the sealing layer is located on the top surface of the internal winding core, the pole penetrates the sealing layer and contacts the internal winding core, and the top cover is located on the top surface of the sealing layer; the inverter model is thermally simulated, and based on the result of the thermal simulation, at least one heat dissipation parameter of the inverter is adjusted, and the heat dissipation parameter includes: at least one of the size of the heat sink, the model of the heat dissipation device, or the extension depth of the boss toward the accommodating cavity.

[0006] In some embodiments, before obtaining the result of the thermal simulation processing, it also includes: obtaining the temperature of the capacitor model and the resistance of the capacitor model, and drawing a curve corresponding to the temperature of the capacitor model and the resistance of the capacitor model. During the thermal simulation processing, the current resistance is obtained according to the current temperature of the capacitor model.

[0007] In some embodiments, the step of obtaining the temperature of the capacitor model includes: selecting several test points on the shell, and taking the average value of the temperatures of the several test points as the current temperature of the capacitor model, and drawing a curve corresponding to the temperature of the capacitor model and the resistance value of the capacitor model according to the current temperature of the capacitor model.

[0008] In some embodiments, the test points are grouped into three, and the test points in each group are arranged on the outer shell along a direction from the sealing layer toward the inner winding core.

[0009] In some embodiments, the reactance model includes: an inner core, a bus, an insulating layer and a coil, the bus is located on the side wall of the inner core, and the bus includes at least two bus pins, the insulating layer surrounds part of the bus pins and part of the inner core, and the coil is at least arranged on the outer wall of part of the insulating layer; the step of forming the reactance model includes: obtaining actual physical parameters of the inner core, the bus, the insulating layer and the coil, and establishing the reactance model based on the actual physical parameters.

[0010] In some embodiments, the side wall of the boss facing the heat dissipation device and the side wall of the boss facing the reactance model have a plurality of through holes.

[0011] In some embodiments, the boss is formed integrally with the housing model by die casting.

[0012] In some embodiments, after forming the capacitance model and before forming the reactance model, the method further includes: forming a heat insulation board on the bottom surface of the capacitance model, and separating the capacitance model and the reactance model by the heat insulation board.

[0013] In some embodiments, after forming the thermal insulation board, the method further includes: forming a thermal insulation layer on the surface of the thermal insulation board.

[0014] According to some embodiments of the present disclosure, on the other hand, an inverter structure is provided, which is formed by using the above-mentioned inverter structure design method based on thermal simulation.

[0015] The technical solution provided by the embodiments of the present disclosure has at least the following advantages: by dividing the capacitor model into five parts: an internal winding core, an outer shell, a sealing layer, a pole and a top cover, the accuracy of the capacitor model in the inverter and the actual capacitor can be improved, thereby improving the accuracy of the thermal simulation model; by improving the accuracy of the capacitor model, the authenticity and practicality of the thermal simulation results can be improved during the thermal simulation process of the established inverter model; the structure of the inverter model can be adjusted according to the more practical thermal simulation results, thereby making the heat dissipation performance of the established inverter model better. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings, and these exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise specified, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the traditional technology, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians with inadequate skills, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 A flow chart of a method for designing a frequency converter structure based on thermal simulation according to an embodiment of the present disclosure;

[0018] Figure 2 A schematic diagram of the structure of a frequency converter model provided by an embodiment of the present disclosure;

[0019] Figure 3 A schematic diagram of the structure of another inverter model provided by an embodiment of the present disclosure;

[0020] Figure 4 A schematic diagram of the structure of another inverter model provided by an embodiment of the present disclosure;

[0021] Figure 5 A schematic diagram of a capacitor model provided in one embodiment of the present disclosure;

[0022] Figure 6 A schematic diagram of the structure of a reactance model provided by an embodiment of the present disclosure;

[0023] Figure 7 A schematic diagram of the structure of another reactance model provided in one embodiment of the present disclosure. DETAILED DESCRIPTION

[0024] As can be seen from the background technology, capacitors are heat-sensitive devices. In order to ensure the life requirements, their allowable temperature rise is generally low, mostly controlled below 15°C, while the temperature rise tolerance of reactance is higher, up to 100°C. Therefore, in previous designs, capacitors and reactances are often placed separately, usually in two cavities, which makes the inverter larger.

[0025] In the prior art, regarding the heat dissipation simulation evaluation of capacitors and reactances, the capacitor is usually directly equivalent to a cylinder, and the thermal conductivity (axial and radial), specific heat capacity, density and other physical parameters of the entire capacitor are measured as input conditions for the simulation; the reactance is simplified into a solid block. However, this equivalent method often causes a large deviation in the results of the thermal simulation processing. Therefore, in order to ensure that the inverter has sufficient heat dissipation capacity, a large heat dissipation margin is usually reserved. The large heat dissipation margin will also increase the cost.

[0026] The present disclosure implements a method for designing a frequency converter structure based on thermal simulation. By placing a capacitor model and a reactance model in the same accommodation cavity, the volume of the frequency converter can be reduced. The present disclosure implements divide the capacitor model into an internal winding core, an outer shell, a sealing layer, a pole and a top cover, thereby improving the simulation accuracy of the capacitor model. Therefore, in the process of thermal simulation evaluation, the capacitor model provided by the present disclosure implement is closer to the actual capacitor model, thereby reducing the deviation between the results of the thermal simulation processing and the actual application, and correspondingly reducing the reserved heat dissipation margin and reducing the cost accordingly.

[0027] The following will describe the various embodiments of the present disclosure in detail with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that in the various embodiments of the present disclosure, many technical details are provided in order to enable the reader to better understand the present disclosure. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present disclosure can be implemented.

[0028] refer to Figure 1 , Figure 1 A flow chart of a method for designing a frequency converter structure based on thermal simulation is provided in an embodiment of the present disclosure.

[0029] In some embodiments, a method for designing a frequency converter structure based on thermal simulation may include the following steps:

[0030] Step S11: Establish an inverter model, which includes a shell model, a capacitor model and a reactance model. The shell model includes a accommodating cavity; the shell model also includes a boss, which extends from the bottom surface of the shell model toward the accommodating cavity; the shell model also includes a heat sink, and the heat sink faces the accommodating cavity; the capacitor model and the reactance model are located in the accommodating cavity, the capacitor model is located above the reactance model, and the reactance model is directly opposite to the boss; the shell model also includes a radiator, which extends from the top surface of the inverter model toward the accommodating cavity; wherein the capacitor model includes: an internal winding core, an outer shell, a sealing layer, a pole and a top cover, the outer shell surrounds the internal winding core, the sealing layer is located on the top surface of the internal winding core, the pole penetrates the sealing layer and contacts with the internal winding core, and the top cover is located on the top surface of the sealing layer.

[0031] An inverter model is established in the thermal simulation model, and the actual physical parameters are input into the thermal simulation model according to the physical parameters corresponding to the actual production conditions. Taking the establishment of the capacitor model as an example, the actual physical parameters of the internal winding core, shell, sealing layer, pole and top cover are tested respectively, such as thermal conductivity, size and density, and the physical parameters corresponding to each test part are input into the thermal simulation model to establish the capacitor model. The capacitor model established by this method is closer to the actual capacitor.

[0032] Step S12: Perform thermal simulation on the inverter model, and adjust at least one heat dissipation parameter of the inverter based on the result of the thermal simulation, the heat dissipation parameter including: at least one of the size of the radiator, the model of the heat dissipation device, or the extension depth of the boss toward the accommodating cavity.

[0033] It should be noted that the results of thermal simulation processing need to be combined with the selection characteristics of the capacitor model and the reactance model, the actual product life requirements of the inverter and the safety derating standards to determine the allowable temperature rise of the capacitor model and the reactance model, and make a judgment by obtaining the temperature of the capacitor model and the reactance model after the thermal simulation processing. When the results of thermal simulation processing do not meet the allowable temperature rise of the capacitor model and the reactance model, the heat dissipation capacity of the inverter model is improved by adjusting at least one of the size of the radiator, the model of the heat dissipation device, or the extension depth of the boss toward the accommodating cavity, until the results of thermal simulation processing meet the allowable temperature rise of the capacitor model and the reactance model.

[0034] It can be understood that the larger the size of the radiator, the stronger the thermal conductivity of the radiator, and the thermal conductivity of the radiator can be improved by increasing the size of the radiator; taking the heat dissipation device as a cooling fan as an example, the model of the cooling fan is related to the maximum airflow it can provide, and accordingly, the larger the maximum airflow that can be provided, the stronger the heat dissipation capacity of the cooling fan; the deeper the depth of the boss extending toward the accommodating cavity, the greater the airflow provided by the heat dissipation device obtained by the corresponding reactance model, and the shallower the depth of the boss extending toward the accommodating cavity, the greater the airflow provided by the heat dissipation device obtained by the corresponding capacitance model, and the airflow distribution of the heat dissipation device can be adjusted by adjusting the depth of the boss extending toward the accommodating cavity.

[0035] refer to Figures 2 to 4 , Figure 2 A perspective of the inverter model provided by the embodiment of the present disclosure, Figure 3 Another perspective of the frequency converter model provided by the embodiment of the present disclosure is as follows: Figure 4 A schematic diagram of the internal structure of the inverter model improved according to the embodiment of the present disclosure.

[0036] Specifically, the inverter model includes a shell model 100, a capacitor model 110 and a reactance model 120, and the shell model 100 includes a accommodating cavity 130; the shell model 100 also includes a boss 103, and the boss 103 extends from the bottom surface of the shell model 100 toward the accommodating cavity 130; the shell model 100 also includes a heat sink 140, and the heat sink 140 faces the accommodating cavity 130; the capacitor model 110 and the reactance model 120 are located in the accommodating cavity 130, the capacitor model 110 is located above the reactance model 120, and the reactance model 120 is opposite to the boss 103; the shell model 100 also includes a radiator 104, and the radiator 104 extends from the top surface of the inverter model toward the accommodating cavity 130.

[0037] In some embodiments, the housing model 100 may include an upper housing model 101 and a lower housing model 102 , and the upper housing model 101 and the lower housing model 102 are detachably assembled.

[0038] In some embodiments, the lower shell model 102 is also provided with a heat dissipation device filter cover 105, and the heat dissipation device filter cover 105 is directly opposite to the heat dissipation device 140. The heat dissipation device filter cover 105 can block external dust, thereby preventing dust outside the inverter model from entering the inverter, thereby improving the reliability of the inverter model, and then improving the service life of the inverter model. The lower shell model 102 is also provided with an air hole 106, and the air hole 106 is arranged opposite to the heat dissipation device 140. The heat dissipation device 140 and the air hole 106 cooperate with each other, so that external cold air enters the inverter model, thereby reducing the internal temperature of the inverter model and improving the heat dissipation capacity of the inverter model.

[0039] In some embodiments, a circuit board is also provided on the upper shell model 101, and the heat sink 104 is adjacent to the circuit board. The heat on the circuit board can be dissipated through the heat sink 104, thereby ensuring the normal operation of the chip on the circuit board, and improving the operating stability of the inverter model, thereby improving the reliability of the inverter model.

[0040] In some embodiments, the side wall of the boss 103 facing the heat sink 140 and the side wall of the boss 103 facing the reactance model 120 may have a plurality of through holes (not shown in the figure). By providing a plurality of through holes on the side walls on both sides of the boss 103, it is convenient for the heat sink 140 to provide airflow to the reactance model 120, thereby cooling the reactance model 120, so that the reactance model 120 is within the temperature rise range.

[0041] It is understandable that the higher the height of the boss 103, the greater the airflow provided by the heat sink 140 to the reactance model 120, and the lower the height of the boss 103, the greater the airflow provided by the heat sink 140 to the capacitance model 110. The greater the airflow, the greater the heat dissipation capacity. By adjusting the height of the boss, the size of the airflow distributed by the heat sink 140 can be adjusted, thereby adjusting the influence of the heat sink 140 on the temperature of the reactance model 120 and the capacitance model 110.

[0042] In some embodiments, the width of the boss 103 in a direction perpendicular to the boss 103 toward the heat sink 140 can also be changed. By changing the width of the boss 103, the flow resistance in the air duct can be changed, thereby achieving air volume distribution of the capacitor model 110 and the reactance model 120, thereby achieving refined thermal control of the capacitor model 110 and the reactance model 120.

[0043] In some embodiments, the boss 103 and the housing model 100 may be integrally die-casted. The mechanical strength of the lower housing model 102 may be improved by integrally die-casting the boss 103 and the housing model 100.

[0044] In some embodiments, after forming the capacitance model 110 and before forming the reactance model 120, the method further includes: forming a heat insulation board 150 on the bottom surface of the capacitance model 110, and separating the capacitance model 110 and the reactance model 120 by the heat insulation board 150. By forming the heat insulation board 150, the influence of the reactance model 120 on the heat radiation of the capacitance model 110 can be reduced.

[0045] In some examples, the reactance model 120 may be formed first, then the heat insulation board 150 may be formed, and finally the capacitance model 110 may be formed. The present application does not limit the order of establishing the components in the inverter model.

[0046] In some embodiments, after forming the heat insulation board 150 , the method further includes: forming a heat insulation layer on the surface of the heat insulation board 150 .

[0047] In some embodiments, the heat insulation layer can be formed by coating the surface of the heat insulation board 150 with radiation-proof heat insulation paint; in other embodiments, a layer of asbestos can be wrapped on the surface of the heat insulation board 150 to form the heat insulation layer. The heat insulation layer can enhance the effect of heat radiation protection.

[0048] In some embodiments, the heat dissipation device 140 may be a heat dissipation fan or an exhaust device, etc., which reduces the temperature inside the inverter by driving airflow.

[0049] refer to Figure 5 , Figure 5 A schematic diagram of the structure of a capacitance model provided in an embodiment of the present disclosure.

[0050] Specifically, the capacitor model 110 includes: an internal winding core 111, an outer shell 112, a sealing layer 113, a pole 114 and a top cover 115. The outer shell 112 surrounds the internal winding core 111, the sealing layer 113 is located on the top surface of the internal winding core 111, the pole 114 penetrates the sealing layer 113 and contacts the internal winding core 111, and the top cover 115 is located on the top surface of the sealing layer 113.

[0051] In some embodiments, the internal core 111 is formed by winding the cathode foil, the separator paper and the anode foil in multiple layers. In the thermal simulation process, the thickness of each layer of the internal core 111 is only tens of microns, and it is impossible to model and calculate according to the actual multi-layer winding. Otherwise, the number of grids is huge and the calculation may not be completed. Therefore, the cathode foil, the separator paper and the anode foil are regarded as a whole, namely the internal core 111.

[0052] In some embodiments, the material of the housing 112 and the top cover 115 may be aluminum, which has a high thermal conductivity and is convenient for conducting the heat of the internal winding core 111. The material of the sealing layer 113 may be rubber, which can prevent the poles 114 from conducting electricity, and the rubber can protect the poles 114. When the capacitor model 110 is impacted, the rubber can absorb part of the stress, thereby protecting the poles 114. The poles 114 can realize electrical connection between the capacitor model and other electronic components or circuits in other inverter models.

[0053] In some embodiments, before obtaining the results of thermal simulation processing, it can also include: obtaining the temperature of the capacitor model 110 and the resistance of the capacitor model 110, and drawing a curve corresponding to the temperature of the capacitor model 110 and the resistance of the capacitor model 110. During the thermal simulation processing, the current resistance is obtained based on the current temperature of the capacitor model 110.

[0054] It can be understood that the heat generated by the actual capacitor is related to the resistance of the actual capacitor, and the resistance of the actual capacitor is greatly affected by its own temperature. The embodiment of the present disclosure draws a curve corresponding to the temperature of the capacitor model 110 and the resistance of the capacitor model 110, obtains the current resistance of the capacitor model 110 by testing the temperature of the capacitor model 110, and then calculates the heat generated by the current capacitor model 110. By improving the accuracy of the thermal simulation processing of the capacitor model 110, the accuracy of the thermal simulation processing results can be improved, thereby improving the reliability of the thermal simulation processing results.

[0055] In some embodiments, the step of obtaining the temperature of the capacitor model 110 may include: selecting several test points on the outer shell 112, and taking the average value of the temperatures of the several test points as the current temperature of the capacitor model 110, and drawing a curve corresponding to the temperature of the capacitor model 110 and the resistance value of the capacitor model 110 according to the current temperature of the capacitor model 110.

[0056] The number of test points can be 2, 3 or 4, etc., and the corresponding number of test points can be selected according to the needs. Taking 4 test points as an example, the 4 test points can be divided into two groups, and the first group of test points and the second group of test points can be relatively set, and the internal core 111 can be divided into three equal parts along the direction of the sealing layer 113 toward the internal core 111, and the test points can be set at the 1 / 3 position and the 2 / 3 position of the internal core. By selecting several test points and taking the average value of the temperature of several test points as the current temperature of the capacitor model 110, the reliability of the current temperature of the capacitor model 110 can be improved, the representativeness of the current temperature can be improved, and the results of the thermal simulation processing can be more accurate.

[0057] In some embodiments, the selected test points may be subjected to repeatability testing, and the average value of the repeated test data may be used as the current test point temperature. The reliability of the temperature and resistance curve of the capacitor model 110 may be improved through the repeatability testing method.

[0058] In some embodiments, the test points are grouped into three, and the test points in each group are arranged on the outer shell 112 along the direction from the sealing layer 113 toward the inner winding core 111 .

[0059] It can be understood that, theoretically, on a horizontal plane perpendicular to the direction from the sealing layer 113 toward the internal winding core 111 , the temperature of each point of the outer shell 112 on the same horizontal plane is the same, so the test points are selected along the direction from the sealing layer 113 toward the internal winding core 111 .

[0060] Taking the number of test points as 3 as an example, the test points are divided into a first test point, a second test point and a third test point, the first test point is closest to the sealing layer 113, and the third test point is farthest from the sealing layer 113. By selecting 3 test points, the temperature of different positions of the capacitor model 110 can be tested, and then by taking the average value of the test temperatures of different test points as the current temperature of the capacitor model 110, the reliability of testing the temperature of the capacitor model 110 can be improved.

[0061] In some embodiments, the distance between the first test point and the second test point can be equal to the distance between the second test point and the third test point. By setting equidistant test points, the temperature difference caused by distance problems can be avoided, and the reliability of the temperature of the test capacitor model 110 can be improved by controlling variables.

[0062] In some other embodiments, the distance between the first test point and the second test point may not be equal to the distance between the second test point and the third test point. The embodiment of the present disclosure does not limit the distance between the test points.

[0063] In some embodiments, the line between the test points is parallel to the direction of the sealing layer 113 toward the inner core 111 ; in other embodiments, the line between the test points intersects with the direction of the sealing layer 113 toward the inner core 111 .

[0064] refer to Figure 6 and Figure 7 , Figure 6 A schematic diagram of a reactance model provided in an embodiment of the present disclosure is shown in FIG. Figure 7 An exploded diagram of a reactance model is provided for an embodiment of the present disclosure.

[0065] Specifically, the reactance model 120 includes: an inner core 121, a bus 122, an insulating layer 123 and a coil 124, the bus 122 is located on the side wall of the inner core 121, and the bus 122 includes at least two bus pins 125, the insulating layer 123 surrounds part of the bus pins 125 and part of the inner core 121, and the coil 124 is at least arranged on the outer wall of part of the insulating layer 123; the steps of forming the reactance model 120 include: obtaining the actual physical parameters of the inner core 121, the bus 122, the insulating layer 123 and the coil 124, and establishing the reactance model 120 based on the actual physical parameters.

[0066] In some embodiments, taking the case where the material of the inner core 121 is silicon steel sheet as an example, the physical parameters of the inner core 121 that need to be input include: the electrical conductivity of the silicon steel sheet, the length of the inner core 121, the height of the inner core 121 and the width of the inner core 121, etc.; taking the material of the bus 122 is copper as an example, the physical parameters of the bus 122 that need to be input include: the electrical conductivity of copper, the number of bus pins 125, the length of the bus 122, the width of the bus 122 and the height of the bus 122, etc.; the physical parameters of the insulating layer 123 that need to be input include: the gap between the insulating layers 123, the dielectric constant of the insulating layer 123, the length of the insulating layer 123, the height of the insulating layer 123, the thickness of the insulating layer 123, etc.; the physical parameters of the coil 124 that need to be input include: the number of coils 124, the total number of turns of the coil 124, the cross-sectional area of ​​the winding, etc. By establishing the reactance model 120 according to the actual physical parameters, the accuracy of the thermal simulation processing can be improved.

[0067] In some embodiments, electrical parameters such as rated voltage, rated reactance, and rated current of the reactance model 120 also need to be input.

[0068] By simplifying the reactance model 120 into four parts consisting of an inner core 121, a bus 122, an insulating layer 123 and a coil 124, wherein gaps are designed for the inner core 121 and the coil 124 according to the actual reactance structure, and by making the reactance model 120 equivalent to the actual reactance structure, the accuracy of the entire thermal simulation process can be improved.

[0069] The embodiment of the present disclosure establishes an inverter model, and simulates the shell model 100, the capacitor model 110 and the reactance model 120 of the inverter model in detail. By placing the capacitor model 110 and the reactance model 120 in the same accommodating cavity 130, the volume of the inverter can be reduced. By dividing the capacitor model 110 into an internal winding core 111, an outer shell 112, a sealing layer 113, a pole 114 and a top cover 115, the simulation accuracy of the capacitor model 110 can be improved. Therefore, in the process of thermal simulation evaluation, the embodiment of the present disclosure provides a capacitor model 110 that is closer to the actual capacitor, thereby reducing the deviation between the results of the thermal simulation processing and the actual application, and correspondingly reducing the reserved heat dissipation margin and the cost. The inverter structure design method based on thermal simulation provided by the embodiment of the present disclosure can provide a direction for designing an inverter that takes into account both miniaturization and heat dissipation performance.

[0070] Another embodiment of the present disclosure further provides a frequency converter structure, which can be formed by using some or all of the above steps.

[0071] Those skilled in the art can understand that the above-mentioned embodiments are specific examples for implementing the present disclosure, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of the embodiments of the present disclosure. Any person skilled in the art can make their own changes and modifications without departing from the spirit and scope of the embodiments of the present disclosure, so the protection scope of the embodiments of the present disclosure shall be based on the scope defined in the claims.

Claims

1. A method for designing a frequency converter structure based on thermal simulation, characterized in that: include: A frequency converter model is established, wherein the frequency converter model includes a shell model, a capacitor model and a reactance model, wherein the shell model includes a receiving cavity; the shell model also includes a boss, wherein the boss extends from the bottom surface of the shell model toward the receiving cavity; the shell model also includes a heat sink, wherein the heat sink faces the receiving cavity; the capacitor model and the reactance model are located in the receiving cavity, wherein the capacitor model is located above the reactance model, and the reactance model is directly opposite to the boss; The housing model further includes a heat sink, and the heat sink extends from the top surface of the inverter model toward the accommodating cavity; The capacitor model includes: an internal winding core, an outer shell, a sealing layer, a pole and a top cover, wherein the outer shell surrounds the internal winding core, the sealing layer is located on the top surface of the internal winding core, the pole penetrates the sealing layer and contacts the internal winding core, and the top cover is located on the top surface of the sealing layer; The inverter model is thermally simulated, and based on the result of the thermal simulation, at least one heat dissipation parameter of the inverter is adjusted, the heat dissipation parameter including: the size of the radiator, the model of the heat dissipation device, the extension depth of the boss toward the accommodating cavity, the height of the boss, or at least one of the width of the boss in a direction perpendicular to the boss toward the heat dissipation device.

2. The inverter structure design method based on thermal simulation according to claim 1, characterized in that: Before obtaining the result of the thermal simulation processing, it also includes: obtaining the temperature of the capacitor model and the resistance of the capacitor model, and drawing a curve corresponding to the temperature of the capacitor model and the resistance of the capacitor model. During the thermal simulation processing, the current resistance is obtained according to the current temperature of the capacitor model.

3. The inverter structure design method based on thermal simulation according to claim 2 is characterized in that: The step of obtaining the temperature of the capacitor model includes: selecting several test points on the shell, and taking the average value of the temperatures of the several test points as the current temperature of the capacitor model, and drawing a curve corresponding to the temperature of the capacitor model and the resistance value of the capacitor model according to the current temperature of the capacitor model.

4. The inverter structure design method based on thermal simulation according to claim 3 is characterized in that: The test points are grouped into three, and the test points in each group are arranged on the outer shell along a direction from the sealing layer toward the inner winding core.

5. The inverter structure design method based on thermal simulation according to claim 1, characterized in that: The reactance model includes: an inner core, a bus, an insulating layer and a coil, the bus is located on the side wall of the inner core, and the bus includes at least two bus pins, the insulating layer surrounds part of the bus pins and part of the inner core, and the coil is at least arranged on the outer wall of part of the insulating layer; the step of forming the reactance model includes: obtaining actual physical parameters of the inner core, the bus, the insulating layer and the coil, and establishing the reactance model based on the actual physical parameters.

6. The inverter structure design method based on thermal simulation according to claim 1, characterized in that: The side wall of the boss facing the heat dissipation device and the side wall of the boss facing the reactance model are provided with a plurality of through holes.

7. The inverter structure design method based on thermal simulation according to claim 1, characterized in that: The boss and the housing model are integrally die-cast.

8. The inverter structure design method based on thermal simulation according to claim 1, characterized in that: After forming the capacitance model and before forming the reactance model, the method further includes: forming a heat insulation board on the bottom surface of the capacitance model, and separating the capacitance model from the reactance model by the heat insulation board.

9. The inverter structure design method based on thermal simulation according to claim 8, characterized in that: After forming the heat insulation board, the method further includes: forming a heat insulation layer on the surface of the heat insulation board.

10. A frequency converter structure, characterized in that: The method for designing a frequency converter structure based on thermal simulation is formed by any one of claims 1 to 9.

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