Low-loss small-size three-phase magnetic integration inversion inductor applied to photovoltaic inverter

Abstract

The low-loss small-size three-phase magnetic integration inversion inductor comprises an aluminum shell, the aluminum shell is provided with an inductor, the inductor is provided with a combined magnetic core, the combined magnetic core comprises an upper jaw magnetic core, the left side and the right side of the lower end face of the upper jaw magnetic core are each connected with a first middle column magnetic core, and the left side and the right side of the lower end face of the upper jaw magnetic core are each connected with a second middle column magnetic core. The lower end faces of the pair of first center pillar magnetic cores are both connected with a first common magnetic core, the left side and the right side of the lower end face of the first common magnetic core are both connected with second center pillar magnetic cores, the lower end faces of the pair of second center pillar magnetic cores are both connected with a second common magnetic core, and the left side and the right side of the lower end face of the second common magnetic core are both connected with third center pillar magnetic cores. The common magnetic core adopts the laminated winding iron-based amorphous block, is high in saturation magnetic flux density and shares a magnetic circuit, can effectively control the height of the inductor, has no air gap in the laminated material, can achieve the minimum magnetic core loss, and adopts the magnetic integration technology, so that the cost is reduced, and the cost is reduced. And the cost is effectively controlled.

Description

Technical Field

[0001] The utility model belongs to the technical field of electronic components, and in particular relates to a low-loss, small-volume three-phase magnetic integrated inverter inductor used in a photovoltaic inverter. Background Art

[0002] Magnetic components play an important role in power electronic converters. However, magnetic components have also become a bottleneck in improving the power density of converters. In order to break through this limitation, it is urgent to miniaturize and integrate magnetic components to improve the overall power density.

[0003] In order to improve efficiency, multiple functional inductors are often used simultaneously in power modules. However, since these inductors are independent of each other, they occupy a large space and have relatively high core losses. This makes it difficult for the power module to achieve high power density, affecting overall performance.

[0004] In order to solve this problem, magnetic integration technology is generally used. This technology integrates multiple inductors together, significantly reducing the size of the inductor and reducing costs. Specifically, the existing integrated inductor design combines two inductors together through a common magnetic core. Since the magnetic fluxes of the two inductors are in opposite directions on the common magnetic core, they cancel each other out, thereby reducing the cross-sectional area of ​​the common magnetic core. However, the current solution also has some problems. For example, the common magnetic core uses a magnetic powder core, which has a low magnetic permeability and a large magnetic resistance. This leads to coupling between each phase, and actual measurement results show that this affects the current waveform.

[0005] To this end, the utility model provides a low-loss, small-volume three-phase magnetic integrated inverter inductor for use in a photovoltaic inverter. Utility Model Content

[0006] In view of the above-mentioned problems existing in the prior art, the purpose of the utility model is to provide a low-loss and small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters, wherein the common magnetic core is made of laminated iron-based amorphous blocks with high saturation flux density and shared magnetic circuit, which can effectively control the height of the inductor, and there is no air gap in the laminated material, so the core loss can be minimized, and magnetic integration technology is adopted, so the cost is effectively controlled.

[0007] The purpose of the utility model can be achieved through the following technical solutions:

[0008] A low-loss and small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters, comprising an aluminum shell, the aluminum shell being equipped with an inductor, the inductor being provided with a combined magnetic core, the combined magnetic core comprising an upper jaw magnetic core, the left and right sides of the lower end surface of the upper jaw magnetic core being connected to a first middle column magnetic core, the lower end surfaces of the first middle column magnetic core being connected to a first common magnetic core, the left and right sides of the lower end surface of the first common magnetic core being connected to a second middle column magnetic core, the lower end surfaces of the second middle column magnetic core being connected to a second common magnetic core, the left and right sides of the lower end surface of the second common magnetic core being connected to a third middle column magnetic core, the lower end surfaces of the third middle column magnetic core being connected to a lower jaw magnetic core, the combined magnetic core being a magnetic core structure of three groups of "mouth"-shaped cores connected end to end;

[0009] The first middle column magnetic core, the second middle column magnetic core and the third middle column magnetic core are all wound with coils, and the coils are vertically wound with flat wires. A first isolation plate is provided between the upper magnetic core and the coil, and a first isolation plate is also provided between the lower magnetic core and the coil. A second isolation plate is provided between the first common magnetic core and the coil, and a second isolation plate is also provided between the second common magnetic core and the coil.

[0010] The first common magnetic core and the second common magnetic core are made of laminated sheets wound around an iron-based amorphous block, and the magnetic permeability of the iron-based amorphous block is between 300 and 1000u.

[0011] As a further preferred technical solution of the utility model, the cross-sections of the upper magnetic core and the lower magnetic core are both in the shape of a racetrack or a rounded rectangle.

[0012] As a further preferred technical solution of the present invention, the cross-sections of the first middle column magnetic core, the second middle column magnetic core and the third middle column magnetic core are all circular, square or elliptical.

[0013] As a further preferred technical solution of the present invention, the cross-sections of the first common magnetic core and the second common magnetic core are both rectangular or square.

[0014] As a further preferred technical solution of the utility model, the first isolation plate is provided with a group of columns with a runway-shaped or rounded rectangular outer contour, and the columns of the first isolation plate are provided with two groups of circular, square or elliptical through holes for nesting with the first middle column magnetic core or the second middle column magnetic core, and the upper end surface of the column of the first isolation plate is provided with an extended hook along the circumferential direction, and extended rectangular blocks are provided on both sides of the lower end surface of the column of the first isolation plate.

[0015] As a further preferred technical solution of the utility model, the second isolation plate includes two groups of columns with runway-shaped or rounded rectangular outlines, and the two groups of columns of the second isolation plate are each provided with two groups of circular, square or elliptical through holes for nesting with the first middle column magnetic core, the second middle column magnetic core and the third middle column magnetic core, and the two groups of columns of the second isolation plate are connected by an extended rectangular block.

[0016] As a further preferred technical solution of the utility model, the aluminum shell is provided with a accommodating chamber with a front opening for loading the inductor, the outer contour of the accommodating chamber is similar to the outer contour of the inductor, and the bottom of the accommodating chamber is also provided with an arc-shaped protrusion similar to the outer contour of the inductor, and the arc-shaped protrusion is placed between the coils of the pair of first middle column magnetic cores, the pair of second middle column magnetic cores and the pair of third middle column magnetic cores. An annular groove is provided on the outer peripheral ring edge of the front opening of the aluminum shell, and connecting holes or connecting protrusions are provided at the four inner corners of the annular groove. An extension hole portion is provided in the middle and upper inner part of the annular groove, and the outer bottom surface, the outer left side surface and the outer right side surface of the aluminum shell are densely covered with neatly arranged fins.

[0017] As a further preferred technical solution of the utility model, the pair of coils wound outside the first middle column magnetic core form a series connection, the pair of coils wound outside the second middle column magnetic core form a series connection, and the pair of coils wound outside the third middle column magnetic core form a series connection;

[0018] The magnetic flux directions of the upper magnetic core and the second common magnetic core are the same, the magnetic flux directions of the first common magnetic core and the lower magnetic core are the same, the magnetic flux directions of the upper magnetic core and the lower magnetic core are opposite, the magnetic flux directions of the coils wound around the pair of second middle column magnetic cores and the coils wound around the pair of first middle column magnetic cores are opposite, and the magnetic flux directions of the coils wound around the pair of second middle column magnetic cores and the coils wound around the pair of third middle column magnetic cores are also opposite.

[0019] As a further preferred technical solution of the utility model, the upper magnetic core and the lower magnetic core are an integral part made of iron silicon or iron silicon aluminum, and the upper magnetic core, the first middle column magnetic core, the first common magnetic core, the second middle column magnetic core, the second common magnetic core, the third middle column magnetic core and the lower magnetic core are fixed with epoxy resin single-component glue.

[0020] As a further preferred technical solution of the present invention, the first isolation board and the second isolation board are both epoxy FR4 boards.

[0021] As described above, the utility model provides a low-loss and small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters, which has the following beneficial effects:

[0022] 1. The utility model utilizes the above-mentioned low-loss and small-volume three-phase magnetic integrated inverter inductor applied to photovoltaic inverters. Compared with the prior art, the common magnetic core adopts a laminated iron-based amorphous block, with high saturation flux density and a shared magnetic circuit, which can effectively control the height of the inductor, and there is no air gap in the laminated material, so the core loss can reach the minimum value. The use of iron-based amorphous can completely compensate for the high iron-silicon loss and large DC bias attenuation factors.

[0023] 2. The utility model utilizes the above-mentioned low-loss and small-volume three-phase magnetic integrated inverter inductor applied to photovoltaic inverters. Compared with the prior art, it adopts magnetic integration technology, a shared magnetic core, and a high-magnetic-permeability laminated winding iron-based amorphous block material to achieve decoupling. Compared with the traditional solution, it can save two upper and lower jaw magnetic cores and reduce the volume of the inductor, which can greatly reduce iron loss and copper loss, realize the weight reduction of the inductor, and reduce the production cost.

[0024] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0026] Figure 1 This is a schematic diagram of the structure of a low-loss, small-volume three-phase magnetic integrated inverter inductor applied to a photovoltaic inverter in the utility model application;

[0027] Figure 2 This is a schematic diagram of an aluminum shell structure of a three-phase magnetic integrated inverter inductor with low loss and small volume applied to a photovoltaic inverter applied for by the utility model;

[0028] Figure 3 This is a schematic diagram of the inductor structure of a low-loss, small-volume three-phase magnetic integrated inverter inductor applied to a photovoltaic inverter in the utility model application;

[0029] Figure 4 This is a schematic diagram of a combined magnetic core structure of a three-phase magnetic integrated inverter inductor with low loss and small volume applied to a photovoltaic inverter applied by the utility model;

[0030] Figure 5 This is a schematic diagram of the structure of a first isolation board of a low-loss and small-volume three-phase magnetic integrated inverter inductor applied to a photovoltaic inverter in the utility model application;

[0031] Figure 6 This is a schematic diagram of the structure of a second isolation board of a low-loss, small-volume three-phase magnetic integrated inverter inductor applied to a photovoltaic inverter in the utility model application.

[0032] Summary of Figure Numbers:

[0033] 100, aluminum shell; 110, accommodating chamber; 120, arc-shaped protrusion; 130, annular groove; 140, connecting hole; 150, connecting protrusion; 160, extended hole portion; 170, fin; 200, inductor; 300, combined magnetic core; 310, upper jaw magnetic core; 320, first middle column magnetic core; 330, first common magnetic core; 340, second middle column magnetic core; 350, second common magnetic core; 360, third middle column magnetic core; 370, lower jaw magnetic core; 400, coil; 500, first isolation plate; 510, through hole; 520, extended hook portion; 530, extended rectangular parallelepiped; 600, second isolation plate. DETAILED DESCRIPTION

[0034] The following is a description of the implementation of the present invention by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0035] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions that can be implemented in this utility model, so they have no substantial technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that can be produced by the utility model and the purposes that can be achieved, should still fall within the scope of the technical content disclosed in this utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of this utility model. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope of the implementation of this utility model. The specific structure can be described with reference to the drawings of the patent application.

[0036] The utility model provides a low-loss and small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters. Please refer to Figures 1 to 6As shown, it includes an aluminum shell 100, the aluminum shell 100 is equipped with an inductor 200, the inductor 200 is provided with a combined magnetic core 300, the combined magnetic core 300 includes an upper jaw magnetic core 310, the left and right sides of the lower end surface of the upper jaw magnetic core 310 are connected to a first middle column magnetic core 320, the lower end surfaces of the pair of first middle column magnetic cores 320 are connected to the first common magnetic core 330, the left and right sides of the lower end surface of the first common magnetic core 330 are connected to a second middle column magnetic core 340, the lower end surfaces of the pair of second middle column magnetic cores 340 are connected to the second common magnetic core 350, the left and right sides of the lower end surface of the second common magnetic core 350 are connected to a third middle column magnetic core 360, the lower end surfaces of the pair of third middle column magnetic cores 360 are connected to the lower jaw magnetic core 370, and the combined magnetic core 300 is a magnetic core structure of three groups of "mouth"-shaped cores connected end to end;

[0037] The first middle column magnetic core 320, the second middle column magnetic core 340 and the third middle column magnetic core 360 ​​are all wound with a coil 400, and the coil 400 is vertically wound with a flat wire. A first isolation plate 500 is provided between the upper magnetic core 310 and the coil 400, and a first isolation plate 500 is also provided between the lower magnetic core 370 and the coil 400. A second isolation plate 600 is provided between the first common magnetic core 330 and the coil 400, and a second isolation plate 600 is also provided between the second common magnetic core 350 and the coil 400.

[0038] The first common magnetic core 330 and the second common magnetic core 350 are made of laminated iron-based amorphous blocks wound around each other, and the magnetic permeability of the iron-based amorphous blocks is between 300 and 1000u.

[0039] It should be noted that: because the magnetic flux of the laminated wound iron-based amorphous block is relatively high, an insulating paper may be added between the first common magnetic core 330 and the first middle column magnetic core 320 as an air gap to achieve the magnetic permeability required for actual use;

[0040] The magnetic integration technology is adopted to integrate the three-phase inductor 200 into one. While reducing the volume of the inductor 200, the number of turns can be reduced to achieve the same performance as the traditional solution, which can greatly reduce the iron loss and copper loss, realize the advantages of light weight, low iron loss and low copper loss of the inductor 200, and reduce the manufacturing production cost.

[0041] Specifically, the specific structures of the upper magnetic core 310 and the lower magnetic core 370 are shown below. Figure 4 As shown, in this embodiment, the cross-sections of the upper magnetic core 310 and the lower magnetic core 370 are both in the shape of a racetrack or a rounded rectangle.

[0042] Specifically, the specific structures of the first middle column magnetic core 320, the second middle column magnetic core 340 and the third middle column magnetic core 360 ​​are as follows. Figure 4As shown, in this embodiment, the cross sections of the first center column magnetic core 320 , the second center column magnetic core 340 , and the third center column magnetic core 360 ​​are all circular, square, or elliptical.

[0043] Specifically, the specific structures of the first common magnetic core 330 and the second common magnetic core 350 are as follows. Figure 4 As shown, in this embodiment, the cross-sections of the first common magnetic core 330 and the second common magnetic core 350 are both rectangular or square.

[0044] Specifically, the specific structure of the first isolation plate 500 is as follows. Figure 5 As shown, in this embodiment, the first isolation plate 500 is provided with a group of columns with a runway-shaped or rounded rectangular outline, and two groups of circular or square or elliptical through holes 510 for nesting with the first middle column magnetic core 320 or the second middle column magnetic core 340 are opened on the column of the first isolation plate 500, and three groups of extended hooks 520 are provided on the upper end surface of the column of the first isolation plate 500 along the circumferential direction, and extended rectangular bodies 530 are provided on both sides of the lower end surface of the column of the first isolation plate 500.

[0045] Specifically, the specific structure of the second isolation plate 600 is as follows. Figure 6 As shown, in this embodiment, the second isolation plate 600 includes two groups of columns with runway-shaped or rounded rectangular outlines, and the two groups of columns of the second isolation plate 600 are each provided with two groups of circular or square or elliptical through holes 510 for nesting with the first middle column magnetic core 320, the second middle column magnetic core 340 and the third middle column magnetic core 360, and the two groups of columns of the second isolation plate 600 are connected by three groups of extended rectangular bodies 530.

[0046] Specifically, the specific structure of the aluminum shell 100 is as follows. Figure 2 As shown, in this embodiment, the aluminum shell 100 is provided with a accommodating chamber 110 with a front opening for loading the inductor 200, the outer contour of the accommodating chamber 110 is similar to the outer contour of the inductor 200, and the bottom of the accommodating chamber 110 is also provided with an arc-shaped protrusion 120 similar to the outer contour of the inductor 200, and the arc-shaped protrusion 120 is placed between the coils 400 of the pair of first middle column magnetic cores 320, the pair of second middle column magnetic cores 340 and the pair of third middle column magnetic cores 360. An annular groove 130 is provided on the outer peripheral ring edge of the front opening of the aluminum shell 100, and the inner four corners of the annular groove 130 are provided with connecting holes 140 or connecting protrusions 150, and the inner middle upper part of the annular groove 130 is provided with an extension hole portion 160, and the outer bottom surface, the outer left side surface and the outer right side surface of the aluminum shell 100 are densely covered with neatly arranged fins 170.

[0047] The pair of coils 400 wound around the first center column magnetic core 320 form a series connection, the pair of coils 400 wound around the second center column magnetic core 340 form a series connection, and the pair of coils 400 wound around the third center column magnetic core 360 ​​form a series connection;

[0048] The magnetic flux directions of the upper magnetic core 310 and the second common magnetic core 350 are the same, the magnetic flux directions of the first common magnetic core 330 and the lower magnetic core 370 are the same, the magnetic flux directions of the upper magnetic core 310 and the lower magnetic core 370 are opposite, the magnetic flux directions of the coil 400 wound around the pair of second middle column magnetic cores 340 and the coil 400 wound around the pair of first middle column magnetic cores 320 are opposite, and the magnetic flux directions of the coil 400 wound around the pair of second middle column magnetic cores 340 and the coil 400 wound around the pair of third middle column magnetic cores 360 are also opposite.

[0049] It should be noted that: the coupling effect of the magnetic flux of adjacent windings passing through the shared high magnetic permeability winding is offset, and the magnetic coupling coefficient between multiple windings is low. For example: the coupling effect of the magnetic flux of the pair of first middle column magnetic core 320 outer winding coil 400 and the pair of second middle column magnetic core 340 outer winding coil 400 passing through the first common magnetic core 330 is offset, and multiple windings can work independently, that is, the pair of first middle column magnetic core 320 outer winding coil 400, the pair of second middle column magnetic core 340 outer winding coil 400 and the pair of third middle column magnetic core 360 ​​outer winding coil 400 can all work independently.

[0050] In this embodiment, the upper core 310 and the lower core 370 are an integral part made of iron silicon or sendust. The magnetic permeability of conventional iron silicon and sendust magnetic powder cores is between 26 and 125u. The upper core 310, the first middle column core 320, the first common core 330, the second middle column core 340, the second common core 350, the third middle column core 360 ​​and the lower core 370 are fixed with epoxy resin single-component glue.

[0051] In this embodiment, the first isolation plate 500 and the second isolation plate 600 are both epoxy FR4 plates.

[0052] When assembling the low-loss and small-volume three-phase magnetic integrated inverter inductor applied to the photovoltaic inverter of the utility model application, refer to Figures 1 to 6As shown, firstly, the coil 400 is wound, and the coil 400 is wound vertically with a flat wire. After the six groups of the coil 400 are wound, they are respectively loaded into a pair of first middle column magnetic cores 320, a pair of second middle column magnetic cores 340 and a pair of third middle column magnetic cores 360. Then, a first isolation plate 500 or a second isolation plate 600 is added to the upper and lower parts of the coil 400 to isolate the coil 400 from the upper jaw magnetic core 310, the lower jaw magnetic core 370, the first common magnetic core 330 and the second common magnetic core 350. Then, the upper jaw magnetic core 310 is spliced ​​with a pair of first middle column magnetic cores 320, and the pair of first middle column magnetic cores 320 is spliced ​​with the first common magnetic core 330. The first common magnetic core 330 is spliced ​​with a pair of second middle column magnetic cores 340, the pair of second middle column magnetic cores 340 are spliced ​​with the second common magnetic core 350, the second common magnetic core 350 is spliced ​​with a pair of third middle column magnetic cores 360, the pair of third middle column magnetic cores 360 are spliced ​​with the lower jaw magnetic core 370, the upper jaw magnetic core 310, the pair of first middle column magnetic cores 320, the first common magnetic core 330, the pair of second middle column magnetic cores 340, the second common magnetic core 350, the pair of third middle column magnetic cores 360 and the lower jaw magnetic core 370 are fixed with epoxy resin single-component glue, and after the assembly is completed, the inductor 200 is installed in the aluminum shell 100 and filled with thermal conductive glue.

[0053] As described above, the utility model provides a low-loss and small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters, which has the following beneficial effects:

[0054] 1. The utility model utilizes the above-mentioned low-loss and small-volume three-phase magnetic integrated inverter inductor applied to photovoltaic inverters. Compared with the prior art, the common magnetic core adopts a laminated iron-based amorphous block, with high saturation flux density and a shared magnetic circuit, which can effectively control the height of the inductor 200, and there is no air gap in the laminated material, so the core loss can reach the minimum value. The use of iron-based amorphous can completely compensate for the high iron-silicon loss and large DC bias attenuation factors.

[0055] 2. The utility model utilizes the above-mentioned low-loss and small-volume three-phase magnetic integrated inverter inductor applied to photovoltaic inverters. Compared with the prior art, it adopts magnetic integration technology, a shared magnetic core, and a high-magnetic-permeability laminated winding iron-based amorphous block material to achieve decoupling. Compared with the traditional solution, it can save two upper and lower jaw magnetic cores 370, and reduce the volume of the inductor 200, which can greatly reduce iron loss and copper loss, realize the weight reduction of the inductor 200, and reduce the production cost.

[0056] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A low-loss, small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters, characterized in that: It comprises an aluminum shell, the aluminum shell is equipped with an inductor, the inductor is provided with a combined magnetic core, the combined magnetic core comprises an upper jaw magnetic core, the left side and the right side of the lower end surface of the upper jaw magnetic core are connected to a first middle column magnetic core, the lower end surface of the first middle column magnetic core is connected to a first common magnetic core, the left side and the right side of the lower end surface of the first common magnetic core are connected to a second middle column magnetic core, the lower end surface of the second middle column magnetic core is connected to a second common magnetic core, the left side and the right side of the lower end surface of the second common magnetic core are connected to a third middle column magnetic core, the lower end surface of the third middle column magnetic core is connected to the lower jaw magnetic core, and the combined magnetic core is a magnetic core structure of three groups of "mouth"-shaped cores connected end to end; The first middle column magnetic core, the second middle column magnetic core and the third middle column magnetic core are all wound with coils, and the coils are vertically wound with flat wires. A first isolation plate is provided between the upper magnetic core and the coil, and a first isolation plate is also provided between the lower magnetic core and the coil. A second isolation plate is provided between the first common magnetic core and the coil, and a second isolation plate is also provided between the second common magnetic core and the coil. The first common magnetic core and the second common magnetic core are made of laminated sheets wound around an iron-based amorphous block, and the magnetic permeability of the iron-based amorphous block is between 300 and 1000u.

2. According to claim 1, a low-loss, small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters, characterized in that: The cross sections of the upper magnetic core and the lower magnetic core are both in a racetrack shape or a rounded rectangle.

3. According to claim 1, a low-loss and small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters is characterized in that: The cross sections of the first middle column magnetic core, the second middle column magnetic core and the third middle column magnetic core are all circular, square or elliptical.

4. According to claim 1, a low-loss and small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters is characterized in that: The cross sections of the first common magnetic core and the second common magnetic core are both rectangular or square.

5. The low-loss, small-volume three-phase magnetic integrated inverter inductor used in photovoltaic inverters according to claim 1, characterized in that: The first isolation plate is provided with a group of columns with a runway-shaped or rounded rectangular outer contour, and two groups of circular, square or elliptical through holes are opened on the columns of the first isolation plate for nesting with the first middle column magnetic core or the second middle column magnetic core. The upper end surface of the column of the first isolation plate is provided with an extended hook along the circumferential direction, and extended rectangular blocks are provided on both sides of the lower end surface of the column of the first isolation plate.

6. The low-loss, small-volume three-phase magnetic integrated inverter inductor used in photovoltaic inverters according to claim 1, characterized in that: The second isolation plate includes two groups of columns with runway-shaped or rounded rectangular outlines. The two groups of columns of the second isolation plate are each provided with two groups of circular, square or elliptical through holes for nesting with the first middle column magnetic core, the second middle column magnetic core and the third middle column magnetic core. The two groups of columns of the second isolation plate are connected by an extended rectangular block.

7. The low-loss, small-volume three-phase magnetic integrated inverter inductor used in photovoltaic inverters according to claim 1, characterized in that: The aluminum shell is provided with a accommodating chamber with a front opening for loading the inductor, the outer contour of the accommodating chamber is similar to the outer contour of the inductor, and the bottom of the accommodating chamber is also provided with an arc-shaped protrusion similar to the outer contour of the inductor, and the arc-shaped protrusion is placed between the coils of the pair of first middle column magnetic cores, the pair of second middle column magnetic cores and the pair of third middle column magnetic cores. An annular groove is provided on the outer peripheral ring edge of the front opening of the aluminum shell, and connecting holes or connecting protrusions are provided at the four inner corners of the annular groove. An extension hole portion is provided in the middle and upper inner part of the annular groove, and the outer bottom surface, the outer left side surface and the outer right side surface of the aluminum shell are densely covered with neatly arranged fins.

8. A low-loss, small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters according to any one of claims 1 to 7, characterized in that: The pair of coils wound outside the first middle column magnetic core form a series connection, the pair of coils wound outside the second middle column magnetic core form a series connection, and the pair of coils wound outside the third middle column magnetic core form a series connection; The magnetic flux directions of the upper magnetic core and the second common magnetic core are the same, the magnetic flux directions of the first common magnetic core and the lower magnetic core are the same, the magnetic flux directions of the upper magnetic core and the lower magnetic core are opposite, the magnetic flux directions of the coils wound around the pair of second middle column magnetic cores and the coils wound around the pair of first middle column magnetic cores are opposite, and the magnetic flux directions of the coils wound around the pair of second middle column magnetic cores and the coils wound around the pair of third middle column magnetic cores are also opposite.

9. A low-loss, small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters according to any one of claims 1 to 7, characterized in that: The upper magnetic core and the lower magnetic core are an integral part made of iron silicon or iron silicon aluminum. The upper magnetic core, the first middle column magnetic core, the first common magnetic core, the second middle column magnetic core, the second common magnetic core, the third middle column magnetic core and the lower magnetic core are fixed with epoxy resin single-component glue.

10. A low-loss, small-volume three-phase magnetic integrated inverter inductor for photovoltaic inverters according to any one of claims 1 to 7, characterized in that: The first isolation board and the second isolation board are both epoxy FR4 boards.

Images