A vertical winding inductor integrated structure for photovoltaic inversion and a packaging process thereof

Abstract

The application relates to a vertical-winding inductor integrated structure for photovoltaic inversion and a packaging process thereof, and relates to the technical field of magnetic components. The structure comprises a base, a magnetic core assembly, a central partition plate and two symmetrical inductor units. The magnetic core assembly forms two groups of closed magnetic circuits sharing a magnetic core body, and the central partition plate divides the mounting space into upper and lower parts to accommodate the two inductor units, so that the high-efficiency reuse of the magnetic core and the doubling of the power density are realized. Each inductor unit comprises parallel vertical-winding coils, a partition plate assembly inserted between the coils and a flow guide column; a non-closed annular conductor sheet in the partition plate assembly forms a closed loop through the flow guide column. The loop can effectively extract and discharge high-frequency noise energy in the coils, suppress electromagnetic interference, and the reverse magnetic field generated by the induced current can also actively offset the leakage magnetic field, so that the leakage inductance is stabilized and reduced. The application systematically solves the technical bottleneck that the traditional inductor has high loss, large volume and poor heat dissipation under high frequency and high power application.

Description

Technical Field

[0001] This application relates to the technical field of magnetic components, and in particular to an integrated structure of vertically wound inductors for photovoltaic inverters and its packaging process. Background Technology

[0002] The rapid evolution of photovoltaic power generation technology has placed higher demands on the core component of inverters—the power inductor—requiring it to simultaneously meet stringent requirements such as high frequency, high efficiency, high power density, low electromagnetic interference, and high environmental adaptability.

[0003] Traditional inductor structures face significant bottlenecks in high-frequency applications. The commonly used horizontal winding process increases the parasitic capacitance between winding layers, leading to a sharp increase in eddy current losses when the operating frequency exceeds a certain value, resulting in a decrease in overall efficiency. Furthermore, high-frequency switching noise is easily radiated through leakage flux, causing electromagnetic interference problems.

[0004] To handle large currents, traditional designs often employ methods that increase the size of the magnetic core and wire diameter, which directly contradicts the trend towards miniaturization and weight reduction in inverters. Furthermore, improving heat dissipation requires adding heat sinks, suppressing electromagnetic interference requires external shielding, and preventing magnetic saturation requires large air gaps. These improvements are mutually restrictive in terms of performance, size, and cost, making coordinated optimization difficult.

[0005] Therefore, there is an urgent need for an innovative inductor integration solution that can systematically and collaboratively solve the intertwined challenges of power density, high-frequency loss, heat dissipation efficiency, and electromagnetic compatibility, in order to support the development of next-generation high-performance, high-reliability photovoltaic inverters. Summary of the Invention

[0006] To overcome the comprehensive technical problems faced by traditional inductors when applied to high-frequency, high-power photovoltaic inverters, such as high loss, low power density, difficult heat dissipation, and severe electromagnetic interference, this application provides an integrated structure of vertically wound inductors for photovoltaic inverters and its packaging process.

[0007] This application provides a vertically wound inductor integrated structure for photovoltaic inverters, which adopts the following technical solution: A vertically wound inductor integrated structure for photovoltaic inverters includes a base, a magnetic core assembly, a central partition, and inductor units located on both sides of the central partition. The magnetic core assembly is disposed on the base and includes a magnetic core body and a pair of yokes symmetrically disposed on both sides of the magnetic core body. The magnetic core body and the pair of yokes together form two sets of U-shaped magnetic circuits sharing the magnetic core body, and an installation space is formed between the magnetic core body and the yokes. The central partition is sleeved on the magnetic core body and divides the installation space into a symmetrical upper space and a lower space. The two sets of inductor units are respectively disposed in the upper space and the lower space. At least two sets of current-guiding columns are disposed on the base. The inductor units include: An inductor coil, wherein the inductor coil is arranged circumferentially along the core body and is arranged in a vertical winding manner, and multiple sets of the inductor coil are arranged at intervals along the axis of the core body and connected in parallel with each other; A separator assembly, wherein multiple separator assemblies are inserted between adjacent coils, the separator assembly comprising two insulating plates and a non-closed annular conductor sheet disposed between adjacent insulating plates, the conductor sheet having two connecting pins; The two connecting pins of the conductor sheet are electrically connected to different current-conducting columns, and the current-conducting columns are electrically isolated from the inductor coil.

[0008] By adopting the above technical solution, in terms of electromagnetic principles, this structure utilizes a central partition to physically divide the magnetic core, enabling one magnetic core to simultaneously serve two independent inductor units, thus achieving efficient core reuse. The conductor sheet in the partition assembly and the main coil form a tightly coupled "transformer" relationship through a shared magnetic circuit (the conductor sheet acts as a single-turn secondary winding). Simultaneously, the conductor sheet forms a closed, low-impedance electrical circuit through the current-conducting posts. This achieves a significant increase in power density per unit volume; the conductor sheet circuit effectively extracts and discharges high-frequency noise energy from the coil, significantly suppressing electromagnetic interference; according to Lenz's law, the magnetic field generated by the induced current in this circuit cancels out part of the primary leakage magnetic field, thereby actively reducing and stabilizing the overall leakage inductance and improving the dynamic performance of the inductor.

[0009] Furthermore, the magnetic core body is a cylindrical structure with multiple micro air gaps arranged axially inside. The magnetic yoke has an arc-shaped positioning groove on one side parallel to the magnetic core body, and the inductor coil is located between the magnetic core body and the positioning groove.

[0010] By adopting the above technical solution, the distributed micro air gap disperses the concentrated large air gap, significantly enhancing the core's resistance to DC bias saturation, ensuring the inductor remains stable under large current fluctuations, and improving magnetic field uniformity to reduce high-frequency iron losses. The arc-shaped positioning groove matches the outer contour of the inductor coil, thus providing precise radial positioning and stable support for the coil, optimizing mechanical stability and thermal contact.

[0011] Furthermore, the conductor sheet is an annular copper sheet with a slit, and the two connecting pins are located on both sides of the slit.

[0012] By adopting the above technical solution, the gap physically prevents the conductor sheet from forming a continuous conductive loop. This ensures that the conductor sheet does not act as an isolated short-circuit loop, generating large eddy current losses. Its current is entirely driven by electromagnetic induction with the main coil, making its function purely as a highly efficient energy pickup and transfer unit, thus avoiding ineffective heat generation.

[0013] Furthermore, the current guiding columns are arranged in three sets, side by side and spaced apart. The three sets of current guiding columns are column 1, column 2 and column 3 respectively. Two layers of partition assemblies are arranged between adjacent inductor coils. The conductor plate of one set of partition assemblies has two connecting pins connected to column 1 and column 2 respectively, and the conductor plate of the other set of partition assemblies has two connecting pins connected to column 3 and column 2 respectively. The induced magnetic field generated by the conductor plates of the two sets of partition assemblies is in the same direction.

[0014] By adopting the above technical solution, a symmetrical star connection topology with post number two as the common point was constructed, enabling all conductor plates to be connected in parallel through the current-carrying post. This provides a balanced, low-inductance current flow path for induced noise current, which is beneficial for balancing the potential and operating state of each conductor plate; the parallel structure reduces the total parasitic inductance of the circuit and improves the response speed of noise suppression; post number two in the middle serves as a natural potential reference point, simplifying the system grounding design.

[0015] Furthermore, both column one and column three are provided with outwardly extending heat dissipation fins.

[0016] By adopting the above technical solution, the heat dissipation function is mainly assigned to the two side guide columns, which are functionally and spatially separated from the middle converging guide column. The middle column focuses on current collection, while the finned columns on both sides become high-efficiency heat sinks, avoiding the concentration of heat sources at electrical connection points, optimizing the heat dissipation airflow organization, and thus significantly improving the module's heat dissipation capacity and high-temperature operating reliability.

[0017] Furthermore, the insulating board consists of a porous honeycomb ceramic layer and potting epoxy resin filling the pores of the honeycomb ceramic layer. The honeycomb ceramic layer is connected to the end face of the conductor sheet and cured into a single unit by the potting epoxy resin.

[0018] By adopting the above technical solution, honeycomb ceramic is used as the load-bearing skeleton, and high thermal conductivity resin is filled into all its pores through vacuum potting to form a ceramic-resin interpenetrating network structure. The honeycomb ceramic endows the separator with extremely high mechanical strength and rigidity, completely solving the deformation problem under vibration and thermal stress. The three-dimensional interconnected thermally conductive network gives the insulating plate near-metallic thermal conductivity in the in-plane direction, enabling rapid lateral conduction of heat from the conductor sheets and coils to the guiding columns, thus improving internal thermal conductivity efficiency.

[0019] Furthermore, the material of the honeycomb ceramic layer is aluminum nitride or alumina ceramic.

[0020] By adopting the above technical solution and selecting aluminum nitride or aluminum oxide, two engineering ceramics with excellent performance, as the matrix material, the insulation board can simultaneously possess extremely high insulation strength, excellent thermal conductivity, and good mechanical properties.

[0021] Furthermore, the thickness of the conductor sheet in its inner axial region and outer circumferential region is greater than the thickness in its middle circumferential region.

[0022] By employing the above technical solution, and addressing the harsh electromagnetic environment and susceptibility to hotspots in the innermost and outermost turns of the coil, the conductor sheet undergoes morphological optimization through "targeted thickening." Electromagnetically, the thickened area enhances the coupling strength with the coil's edge turns, more effectively suppressing high-frequency oscillations at that location. Thermally, the thickened portion acts as a localized heat sink, improving the ability to absorb and dissipate heat from the edge turns. This achieves precise performance enhancement in critical areas.

[0023] This application provides a packaging process for a vertically wound inductor integrated structure for photovoltaic inverters, which adopts the following technical solution: A packaging process for a vertically wound inductor integrated structure for photovoltaic inverters includes the following steps: Magnetic core assembly fixing: Fix the magnetic core assembly to the base; Inductor unit pre-assembly: Multiple vertically wound inductor coils are alternately assembled with a partition assembly containing conductor sheets to form an inductor unit, and the connecting pins of the conductor sheets are connected to the corresponding current-conducting posts; The dual-unit integration involves mounting the central partition onto the magnetic core assembly and symmetrically mounting the two inductor units on the upper and lower sides of the central partition.

[0024] By adopting the above technical solution, this process route follows a modular and symmetrical integration assembly logic. First, the magnetic core and base are fixed as a foundation, then the upper and lower inductor units are assembled separately, and finally, the entire assembly is completed through a central partition. This ensures the precision and consistency of the dual-unit structure assembly and is a reliable and repeatable manufacturing method for achieving high-density, symmetrical product structures.

[0025] Furthermore, in the inductor unit pre-assembly step, the upper and lower end faces of the assembled inductor coil are flattened and encapsulated to form a thermally conductive and insulating plane.

[0026] By adopting the above technical solution, before assembling the coil and the insulation board, all the grooves between the wires on the coil end face are filled with a high thermal conductivity insulating material and then cured to form a smooth surface. This fundamentally eliminates the microscopic air gap between the coil and the insulation board, reducing the interface thermal resistance by more than an order of magnitude and ensuring unimpeded heat dissipation. At the same time, this encapsulation layer reinforces the coil end, improving the long-term reliability of the product against mechanical vibration and thermal cycling shock.

[0027] In summary, this application includes at least one of the following beneficial technical effects: 1. By using dual-unit magnetic core reuse and integrated design, the inductor power density is significantly improved, which is in line with the trend of miniaturization and lightweighting of photovoltaic inverters.

[0028] 2. By using a closed-loop design of conductor sheet-current guide post, the three major functions of high-frequency noise suppression, leakage inductance stabilization and auxiliary heat dissipation are integrated into a single structure, which comprehensively improves the electrical performance and reliability of the inductor.

[0029] 3. By introducing innovative structures such as honeycomb ceramic composite insulation boards and flattened coil end face packaging, the core bottlenecks of internal heat dissipation, mechanical strength and insulation reliability under high power density have been systematically overcome.

[0030] 4. Through refined design such as functional separation of the flow guide column and targeted thickening of the conductor sheet, the distribution of the internal thermal and electromagnetic fields has been further optimized, ensuring the stable performance and long lifespan of the module under extreme operating conditions. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the integrated structure of the vertically wound inductor for photovoltaic inverter according to Embodiment 1 of this application; Figure 2 This is a schematic diagram of the integrated structure of a vertically wound inductor for photovoltaic inverter according to Embodiment 1 of this application, which mainly shows the position between the current-guiding column and the conductor sheet; Figure 3 This is a schematic diagram of the magnetic core assembly of Embodiment 1 of this application; Figure 4 This is a schematic diagram of the structure of the inductor coil of Embodiment 1 of this application; Figure 5 This is a rear view of Embodiment 1 of this application; Figure 6 yes Figure 5 Cross-sectional schematic diagram of AA and BB in the middle; Figure 7 yes Figure 5 A cross-sectional view of CC. Figure 8 This is a structural schematic diagram of the partition assembly of Embodiment 2 of this application, with a partial cross-sectional view of the partition assembly and a partial enlargement of part D; Figure 9 This is a schematic diagram of the partition assembly of Embodiment 3 of this application, wherein the partition assembly is partially cross-sectional and part E is partially enlarged.

[0032] Reference numerals: 1. Base; 2. Magnetic core assembly; 21. Magnetic core body; 22. Magnetic yoke; 221. Arc-shaped positioning groove; 3. Central partition; 4. Inductor unit; 41. Inductor coil; 42. Partition assembly; 421. Insulating plate; 422. Conductor sheet; 423. Connecting pin; 43. Guide column; 431. Column No. 1; 432. Column No. 2; 433. Column No. 3; 44. Heat dissipation fins. Detailed Implementation

[0033] The following is in conjunction with the appendix Figures 1-9 This application will be described in further detail.

[0034] This application discloses a vertical winding inductor integrated structure for photovoltaic inverters. Example 1

[0035] Reference Figure 1 A vertical winding inductor integrated structure for photovoltaic inverters includes a base 1, a magnetic core assembly 2, a central partition 3, and two symmetrically arranged inductor units 4.

[0036] Reference Figure 1 and Figure 2 The base 1 is a metal plate with good thermal conductivity, such as an aluminum alloy plate. Its function is to provide a stable mechanical mounting reference for the entire inductor structure and can also serve as an auxiliary heat dissipation interface to connect with the inverter housing or heat sink. In this embodiment, the base 1 is provided with an insulating layer on the side near the magnetic core assembly 2, thereby making the base 1 and the magnetic core assembly 2 insulated from each other.

[0037] Reference Figure 2 and Figure 3 The magnetic core assembly 2 is fixed to the base 1 by bonding or welding. The magnetic core assembly 2 is integrally molded from a soft magnetic material with high permeability and low loss (such as an iron-silicon-aluminum magnetic powder core). Its core is a cylindrical magnetic core body 21. On both sides of the magnetic core body 21, a pair of identical magnetic yokes 22 are symmetrically connected. The magnetic yokes 22 are roughly C-shaped, with their ends connected to the top and bottom of the magnetic core body 21, respectively. This allows each magnetic yoke 22 and the magnetic core body 21 to form a closed U-shaped magnetic circuit. Therefore, the entire magnetic core assembly 2 forms two independent U-shaped magnetic rings sharing the central magnetic core body 21, greatly improving the core utilization rate. The cross-sectional area of ​​the magnetic core body 21 is twice the cross-sectional area of ​​the magnetic yoke 22. An arc-shaped positioning groove 221 is precisely machined on the inner sidewall of the magnetic yoke 22, parallel to the magnetic core body 21. Inside the magnetic core body 21, multiple distributed micro air gaps are embedded along its axial direction. These air gaps can effectively store energy, prevent the magnetic core body 21 from saturating under high current DC bias, improve magnetic field uniformity, and reduce high-frequency iron loss.

[0038] Reference Figure 1 and Figure 3The central partition 3 is made of high-strength, high-insulation engineering plastic or epoxy glass cloth, and has a through hole in its center that engages with the magnetic core body 21. The central partition 3 is tightly fitted onto the axial center of the magnetic core body 21, thereby strictly dividing the annular space formed between the magnetic core body 21 and the yoke 22 into two symmetrical and electrically isolated mounting cavities: an upper space and a lower space. To facilitate the installation of the central partition 3 and the inductor unit 4, the magnetic core assembly 2 divides the magnetic core body 21 and the yoke 22 into two symmetrical upper and lower parts along the central direction of the central partition 3.

[0039] Reference Figure 1 Two identical inductor units 4 are respectively housed in the upper and lower spaces. Each inductor unit 4 is composed of three parts: an inductor coil 41, a partition assembly 42, and a current-guiding column 43.

[0040] Reference Figure 3 and Figure 4 The inductor coil 41 is manufactured using a vertical winding process, where the wire is wound radially along the cross-section of the magnetic core body 21, so that multiple turns of wire are located on the same horizontal plane, and the distance between different turns of wire and the axis of the magnetic core body 21 is different. Each inductor unit 4 consists of multiple independent inductor coils 41 connected in parallel. These inductor coils 41 are mounted on the magnetic core body 21 and uniformly arranged along the axis of the magnetic core body 21. All inductor coils 41 use wire of the same specification, are wound with the same winding direction, number of turns and shape, and their starting ends are all connected in parallel to a common input bus, and their ending ends are connected in parallel to a common output bus. The wire in this embodiment is Litz wire or flat copper wire. This multi-strand parallel combined with vertical winding design can significantly reduce skin effect and proximity effect losses during high-frequency operation, while also having excellent high current carrying capacity. In this embodiment, the same inductor coil 41 has two layers in the direction of the magnetic core body 21. The first layer of wires is wound from the outside to the inside and spirals up to the second layer on the side close to the magnetic core body 21. The second layer of wires is wound from the inside to the outside, so that the beginning and end of the same inductor coil 41 are both located on the outside and the induced magnetic field generated by the two layers of wires is in the same direction.

[0041] Reference Figure 5 and Figure 6The number of partition assemblies 42 corresponds to the number of inductor coils 41. Each partition assembly 42 is precisely inserted between two adjacent inductor coils 41. The inductor coils 41 closer to the central partition 3 abut against the central partition 3, while partition assemblies 42 are provided on both sides of the inductor coils 41 farther from the central partition 3. The partition assembly 42 adopts a multi-layered structure, with its main body consisting of two layers of insulating plates 421 made of epoxy resin. Crucially, a non-closed annular conductor sheet 422 is sandwiched between two adjacent insulating plates 421. This conductor sheet 422 is preferably a highly conductive copper sheet, its shape being stamped or etched into a ring with a narrow slit. This slit ensures that the copper sheet cannot form a closed circuit electrically. Solid connecting pins 423 extend from both ends of the conductor sheet 422, located on both sides of the slit. In this embodiment, the slit can be filled with cured insulating adhesive to enhance the insulation effect.

[0042] Reference Figure 3 and 7 The inductor coil 41 and the partition assembly 42 are alternately sleeved on the magnetic core body 21, and the end faces of the inductor coil 41 and the partition assembly 42 abut against each other. The outer walls of the inductor coil 41 and the partition assembly 42 are engaged with the arc-shaped positioning groove 221 of the yoke 22.

[0043] Reference Figure 2 and Figure 6 The base 1 has at least two sets of guide columns 43. Each guide column 43 is a structurally independent and spaced-apart physical entity. The base 1 and the guide columns 43 are connected by an insulating material to prevent electrical connection between the guide columns 43 and the base 1. A connecting conductive strip is provided on the surface of the base 1. The connecting conductive strip electrically connects the guide columns 43 that are connected to the connecting pins 423 at both ends of the same conductor sheet 422, ultimately forming a complete closed loop with the conductor sheet 422, the connecting pins 423, the guide columns 43, and the connecting conductive strip. During operation, the high-frequency noise magnetic field in the inductor coil 41 induces eddy currents in the conductor sheet 422. This induced current is guided to the guide columns 43 through the connecting pins 423, which on the one hand dissipates electromagnetic interference energy, and on the other hand provides a path for heat dissipation. At the same time, the guide columns 43 enable multiple sets of conductor sheets 422 to be connected in parallel. To improve heat dissipation, some of the flow guide columns 43 are equipped with heat dissipation fins 44, which guide energy to the heat dissipation fins 44 for dissipation.

[0044] Reference Figure 6In a preferred embodiment, three parallel guiding columns 43 are fixedly installed on the base 1, which can be named column 1 431, column 2 432, and column 3 433 respectively. The guiding columns 43 are preferably solid or hollow copper strips with rectangular cross-sections to balance conductivity, thermal conductivity, and structural strength. Two layers of partition assemblies 42 are arranged between adjacent inductor coils 41. The two sets of partition assemblies 42 are centrally symmetrical, and the central symmetry plane is the contact surface of the two sets of partition assemblies 42. This allows the two connecting pins 423 of the conductor sheet 422 of one partition assembly 42 to be electrically connected to column 1 431 and column 2 432 respectively; the two connecting pins 423 of the conductor sheet 422 of the other partition assembly 42 are electrically connected to column 3 433 and column 2 432 respectively. This connection method makes the middle column 2 432 the common connection point of the two sets of conductor sheets 422, and the magnetic fields generated by the two conductor sheets 422 are in the same direction. In this embodiment, the No. 1 column 431 and the No. 3 column 433 are electrically connected to each other through a connecting conductive strip, so that the two sets of conductor sheets 422 in the same partition assembly 42 and the three current-guiding columns 43 together form a complete closed electrical circuit.

[0045] Reference Figure 2 To enhance heat dissipation, radially extending metal heat dissipation fins 44 are brazed or embedded on the sides of column 1 431 and column 3 433. Column 2 432 in the middle can serve as the main electrical reference point, while the guide columns 43 with heat dissipation fins 44 on both sides become the core heat sink, thus separating and coordinating the functions of current convergence and heat dissipation.

[0046] Reference Figure 2 The first and third pillars 431 and 433 are interconnected via a conductive strip to form a closed loop. During operation, the high-frequency noise current induced by the conductor sheet 422 flows through this loop. The middle second pillar 432 serves as a common current convergence point and electrical reference point, effectively balancing the potential; the first and third pillars 431 and 433, with heat dissipation fins 44 on both sides, are dedicated to heat dissipation. This design achieves functional separation and spatial coordination of "central current convergence and dual-sided heat dissipation," avoiding heat source concentration and improving heat dissipation efficiency and noise suppression response speed.

[0047] The working principle of Embodiment 1 of this application is as follows: When the inductor is operating, the main power current flows through the parallel inductor coil 41, generating the main magnetic flux. The conductor plate 422 sandwiched between the coils shares the same magnetic core circuit with the coils, equivalent to a highly coupled single-turn secondary winding. The rapidly changing leakage flux and electromagnetic interference noise generated by the high-frequency switching action in the coils induce eddy currents in the conductor plate 422. This induced current is rapidly guided to the large-section current-conducting column 43 through the low-impedance connection pin 423, and finally dissipated efficiently as heat energy through the heat dissipation fins 44. According to the principle of electromagnetic induction, the conductor plate 422 impedes the change in the original magnetic flux, and thus the magnetic field generated by the conductor plate 422 can compensate for part of the leakage flux generated by the coils, thereby reducing and stabilizing the leakage flux of the magnetic core body 21.

[0048] This innovative structure achieves multiple benefits: First, it provides a built-in, distributed electromagnetic interference absorption and discharge channel, significantly improving the electromagnetic compatibility performance of the inductor; second, it effectively reduces and stabilizes leakage inductance through active magnetic field cancellation effect; third, the current guide column 43 and fins constitute a second heat dissipation path independent of the main magnetic core; fourth, the dual-unit shared magnetic core design nearly doubles the power density. Example 2

[0049] Reference Figure 8 The difference between this embodiment and embodiment 1 is that the insulating plate 421 in the partition assembly 42 has been reinforced in terms of material and structure, in order to further improve the overall mechanical reliability, insulation level and heat dissipation efficiency.

[0050] Reference Figure 8 The insulating plate 421 in the partition assembly 42 is not a traditional homogeneous epoxy plate, but rather a composite material structure. Specifically, it is composed of a porous honeycomb ceramic layer and a highly thermally conductive potting epoxy resin completely filling its honeycomb pores, cured together. During preparation, aluminum nitride or alumina ceramic is first used to prepare a honeycomb ceramic skeleton with regular hexagonal pores. This skeleton itself possesses extremely high mechanical strength and excellent thermal conductivity and insulation properties. Then, the conductor sheet 422 is precisely positioned and placed on one side of the honeycomb ceramic skeleton, and together they are placed into a molding mold. Under a high vacuum environment, liquid highly thermally conductive epoxy resin is poured into the mold. The resin, under capillary action, fully wets and fills each ceramic honeycomb pore, and covers the conductor sheet 422 and its connecting pins 423. Finally, after a thermosetting process, the resin, ceramic skeleton, and conductor sheet 422 are firmly bonded together into a single, robust plate.

[0051] The working principle of Embodiment 2 of this application is as follows: The honeycomb ceramic skeleton endows the insulation board 421 with extremely high compressive and bending stiffness and impact toughness, completely solving the problems of easy softening and deformation of traditional epoxy boards at high temperatures and easy generation of micro-cracks in vibration environments, greatly improving the long-term reliability of the inductor under harsh conditions. Secondly, the three-dimensional interconnected thermally conductive network formed by ceramic and potting resin has a thermal conductivity far higher than that of ordinary epoxy boards. It can efficiently transfer the heat generated by the conductor sheet 422 during operation and the heat conducted from the coil to the lateral guide pillars 43 on both sides, fundamentally improving the heat dissipation and heat distribution capabilities inside the module. Example 3

[0052] Reference Figure 9 The difference between this embodiment and Embodiment 1 is that the conductor sheet 422 has been morphologically optimized in order to achieve targeted electromagnetic and thermal coupling enhancement in a specific area of ​​the adjacent inductor coil 41.

[0053] Reference Figure 9 In the flat spiral inductor coil 41, the innermost and outermost turns have different current density distributions, heat dissipation conditions, and leakage magnetic field characteristics compared to the middle turns due to their special geometric positions. To optimize overall performance, the cross-sectional shape of the annular conductor sheet 422 is specially designed: the thickness of the conductor sheet 422 in its circumferential direction (the dimension along the axis of the magnetic core body 21) is no longer uniform. In specific implementation, selective electroplating, lamination, or molding processes can be used to intentionally increase the thickness of the conductor sheet 422 in its inner and outer circumferential edge regions, making it greater than the thickness of its middle circumferential region.

[0054] The working principle of Embodiment 3 of this application is as follows: By increasing the thickness of the inner and outer circumferential edge regions, it is equivalent to increasing the effective cross-sectional area and magnetic coupling strength of the induced eddy currents in the conductor sheet 422 at the corresponding positions of the inner and outer turns of the electromagnetic coil that require special attention. This allows for more effective absorption and suppression of high-frequency oscillation noise that may be generated at these critical locations. Secondly, in terms of thermal management, the locally thickened conductor sheet 422 enables the area near these coil regions prone to hot spots to absorb and dissipate heat more quickly, working in conjunction with the main heat dissipation system of the guide column 43 to achieve a more balanced temperature field distribution.

[0055] This application discloses a packaging process for a vertically wound inductor integrated structure for photovoltaic inverters.

[0056] Reference Figures 1-9 A packaging process for a vertically wound inductor integrated structure for photovoltaic inverters mainly includes the following steps: The first step is to fix the magnetic core assembly 2. The pre-sintered and processed magnetic core assembly 2 is firmly installed in the designated position of the surface-treated base 1 using high thermal conductivity silicone adhesive or mechanical snap-fit ​​structure, ensuring accurate positioning and good contact to facilitate heat conduction.

[0057] The second step is the pre-assembly of inductor unit 4. This is the core assembly stage. First, a high-precision automatic vertical winding machine is used to wind the inductor coil 41 on a special fixture. Closed-loop control ensures the consistency of the number of turns, tension, and shape of multiple inductor coils 41. After winding, a high thermal conductivity insulating material is used to locally pot or coat the upper and lower end faces of the inductor coil 41 and cure it to form two parallel, flattened encapsulation layers. This encapsulation layer completely fills all the wire grooves, forming a smooth, flat, and insulating mechanical surface. Then, the inductor coil 41 and the pre-formed partition assembly 42 are alternately inserted into a ring assembly fixture to form a complete and stable inductor unit 4. The flattened encapsulation layer and the insulating plate 421 abut against each other, achieving perfect surface contact, enhancing the mechanical fixing effect between the coils, and facilitating the timely dissipation of heat generated by the coils through the insulating plate 421.

[0058] The third step is dual-unit integration. Since the magnetic core assembly 2 consists of two symmetrical parts, the two inductor units 4 prepared in the second step are respectively inserted into the two parts of the magnetic core assembly 2. At this point, it should be ensured that all inductor coils 41 are precisely located within the space defined by the outer surface of the magnetic core body 21 and the arc-shaped positioning groove 221 of the yoke portion 22, achieving good radial positioning. Then, the two parts of the magnetic core assembly 2 are inserted into both sides of the central partition 3, and pressed firmly against the two sides of the central partition 3. Finally, the two parts of the magnetic core assembly 2 are connected and fixed using adhesive.

[0059] The fourth step is the installation of the guide posts 43. The guide posts 43 are sequentially passed through the connecting pins 423 extending from the multiple sets of conductor plates 422 and installed at the designated positions on the base 1. Using laser welding or low-temperature Sn-Ag-Cu solder, the connecting pins 423 are reliably welded to the corresponding guide posts 43, forming a low-resistance, high-mechanical-strength electrical connection. Part of the structure also undergoes vacuum potting to enhance the overall structural strength. The working principle of this application embodiment is as follows: A reference is established by precisely fixing the magnetic core assembly 2 to the base 1. The inductor coil 41 is wound, and then the end face of the vertically wound inductor coil 41 is flattened and encapsulated. All micro-grooves between the wires are filled with a high thermal conductivity material and cured, creating a perfect foundation for subsequent heat dissipation. Subsequently, the processed coil and the specially designed partition assembly 42 are alternately assembled into a ring-shaped unit, and the upper and lower units are symmetrically integrated through the central partition 3 to form a compact double-layer electromagnetic structure. Finally, the conductor sheet 422 is welded to the current-guiding column 43 to form a closed damping loop. The coil, partition, magnetic core, and current-guiding column 43 are thermally coupled into a whole, constructing a three-dimensional high-efficiency thermal path from the internal hot spot to the external heat dissipation fins 44. The entire process is interconnected, ultimately producing an integrated inductor with mechanical robustness, excellent thermal management, and stable electromagnetic performance.

[0060] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A vertically wound inductor integrated structure for photovoltaic inverters, characterized in that: The system includes a base (1), a magnetic core assembly (2), a central partition (3), and inductor units (4) located on both sides of the central partition (3). The magnetic core assembly (2) is mounted on the base (1). The magnetic core assembly (2) includes a magnetic core body (21) and a pair of yokes (22) symmetrically arranged on both sides of the magnetic core body (21). The magnetic core body (21) and the pair of yokes (22) together form two sets of U-shaped magnetic circuits sharing the magnetic core body (21). An installation space is formed between the magnetic core body (21) and the yokes (22). The central partition (3) is fitted onto the magnetic core body (21) and divides the installation space into a symmetrical upper space and a lower space. The two sets of inductor units (4) are respectively arranged in the upper space and the lower space. At least two sets of guide columns (43) are provided on the base (1). The inductor unit (4) includes: Inductor coil (41), the inductor coil (41) is arranged circumferentially along the core body (21) and is arranged in a vertical winding manner, and multiple sets of the inductor coil (41) are arranged at intervals along the axis of the core body (21) and connected in parallel with each other; A separator assembly (42), multiple sets of the separator assemblies (42) are inserted between adjacent coils. The separator assembly (42) includes two insulating plates (421) and a non-closed annular conductor sheet (422) disposed between adjacent insulating plates (421). The conductor sheet (422) has two connecting pins (423). The two connecting pins (423) of the conductor sheet (422) are electrically connected to different current-conducting posts (43), and the current-conducting posts (43) are electrically isolated from the inductor coil (41).

2. The photovoltaic inverter vertical winding inductor integrated structure according to claim 1, characterized in that: The magnetic core body (21) is a cylindrical structure with multiple micro air gaps arranged along the axial direction inside. The magnetic yoke (22) has an arc-shaped positioning groove (221) on the side parallel to the magnetic core body (21). The inductor coil (41) is located between the magnetic core body (21) and the positioning groove.

3. The photovoltaic inverter vertical winding inductor integrated structure according to claim 1, characterized in that: The conductor sheet (422) is an annular copper sheet with a slit, and the two connecting pins (423) are located on both sides of the slit.

4. The photovoltaic inverter vertical winding inductor integrated structure according to claim 3, characterized in that: The flow guide column (43) is provided in three sets and arranged in parallel with intervals. The three sets of flow guide columns (43) are column 1 (431), column 2 (432) and column 3 (433) respectively. Two layers of partition assemblies (42) are provided between adjacent inductor coils (41). The two connecting pins (423) of the conductor sheet (422) of one set of partition assemblies (42) are connected to column 1 (431) and column 2 (432) respectively. The two connecting pins (423) of the conductor sheet (422) of the other set of partition assemblies (42) are connected to column 3 (433) and column 2 (432) respectively. The induced magnetic field generated by the conductor sheet (422) of the two sets of partition assemblies (42) has the same direction.

5. The photovoltaic inverter vertical winding inductor integrated structure according to claim 4, characterized in that: Both column 1 (431) and column 3 (433) are provided with outwardly extending heat dissipation fins (44).

6. The integrated structure of a vertically wound inductor for photovoltaic inverters according to claim 1, characterized in that: The insulating plate (421) consists of a porous honeycomb ceramic layer and potting epoxy resin filling the pores of the honeycomb ceramic layer. The honeycomb ceramic layer is connected to the end face of the conductor sheet (422) and cured into one piece by the potting epoxy resin.

7. The photovoltaic inverter vertical winding inductor integrated structure according to claim 6, characterized in that: The material of the honeycomb ceramic layer is aluminum nitride or alumina ceramic.

8. The photovoltaic inverter vertical winding inductor integrated structure according to claim 7, characterized in that: The thickness of the conductor sheet (422) in its inner axial region and outer circumference region is greater than the thickness of its middle circumference region.

9. The packaging process for a vertically wound inductor integrated structure for photovoltaic inverters according to any one of claims 1-8, characterized in that: Includes the following steps: Magnetic core assembly (2) fixing: The magnetic core assembly (2) is fixed on the base (1); Inductor unit (4) pre-assembly: Multiple vertically wound inductor coils (41) are alternately assembled with a partition assembly (42) containing conductor sheets (422) to form an inductor unit (4), and the connecting pins (423) of the conductor sheets (422) are connected to the corresponding current guide posts (43); The dual-unit integration involves mounting the central partition (3) on the magnetic core assembly (2) and symmetrically mounting the two inductor units (4) on the upper and lower sides of the central partition (3).

10. The packaging process for a vertically wound inductor integrated structure for photovoltaic inverters according to claim 9, characterized in that: In the pre-assembly step of the inductor unit (4), the upper and lower end faces of the assembled inductor coil (41) are flattened and encapsulated to form a thermally conductive and insulating plane.

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