Balanced-inductance three-phase LC harmonic filter reactor

Abstract

The three-phase LC harmonic filter reactor comprises three magnetic core assemblies, the three magnetic core assemblies are annularly distributed, each magnetic core assembly comprises an upper cover magnetic core, a lower cover magnetic core and two center pillar magnetic cores, the top ends of the two center pillar magnetic cores are connected with the two ends of the upper cover magnetic core respectively, and the top ends of the two center pillar magnetic cores are connected with the two ends of the lower cover magnetic core respectively. The upper cover magnetic core and the lower cover magnetic core are arranged in the two magnetic core assemblies, the bottom ends of the two middle column magnetic cores are connected with the two ends of the lower cover magnetic core respectively, in the two magnetic core assemblies, every two adjacent middle column magnetic cores form a middle column magnetic core set, the middle column magnetic core sets are sleeved with coils, and the upper cover magnetic core, the lower cover magnetic core and the middle column magnetic cores are all metal magnetic powder cores. According to the structure, the precision of three paths of inductance values can reach the difference within 3%, meanwhile, each phase of inductance has only one coil, the processing difficulty that a traditional coil needs 8-shaped winding is avoided, the number of turns of the three-phase coils is completely the same, the process that a large amount of working hours are spent on adjusting the number of turns of the coils or padding air gaps to meet inductance balance in the production link is reduced, and the production efficiency is improved. Copper material consumption is saved, and production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical components, and in particular to a balanced inductance three-phase LV harmonic filter reactor. Background Art

[0002] Conventional three-phase LC harmonic filter reactors sometimes use a silicon steel core design. However, since the silicon steel core operates at the industrial frequency, the noise level cannot meet the design requirements when the applicable carrier frequency reaches 8 kHz or higher. Other designs use an iron silicon core design, which can solve the noise problem at carrier frequencies of 8 kHz or higher, but the accuracy of the three-way inductance difference is poor.

[0003] Currently, three-phase inductors are arranged in a row, sharing a top core. This results in the middle phase having a higher inductance than the other two groups. Although the inductance of the middle phase can be adjusted by reducing the number of turns of the middle phase inductor (or shortening the length of the middle phase core to form an air gap), it is difficult to ensure that the difference in the three inductances is less than 5%. Summary of the Invention

[0004] In response to the defects in the prior art, the present invention provides a balanced inductance three-phase LC harmonic filter reactor. This structure can ensure that the accuracy of the three-way inductance can reach a difference within 3%. At the same time, each phase inductor has only one coil, avoiding the processing difficulty of the traditional coil requiring an 8-shaped winding. The number of turns of the three-phase coils is exactly the same, which reduces the large amount of work time spent in the production process to adjust the number of coil turns or fill the air gap to meet the inductance balance process, saves copper material usage, and reduces production costs.

[0005] A balanced inductance three-phase LC harmonic filter reactor includes three magnetic core components, which are distributed in a ring shape.

[0006] The magnetic core assembly includes an upper cover magnetic core, a lower cover magnetic core and two middle column magnetic cores, the top ends of the two middle column magnetic cores are respectively connected to the two ends of the upper cover magnetic core, and the bottom ends of the two middle column magnetic cores are respectively connected to the two ends of the lower cover magnetic core.

[0007] In the two magnetic core assemblies, two adjacent middle column magnetic cores form a middle column magnetic core group, and a coil is set on the middle column magnetic core group.

[0008] The upper cover magnetic core, the lower cover magnetic core and the middle column magnetic core are all metal magnetic powder cores.

[0009] Preferably, the metal magnetic powder core is a Sendust magnetic powder core, an Iron Silicon magnetic powder core, an Iron Nickel magnetic powder core, or a magnetic powder core formed by mixing the above three types of magnetic powder cores.

[0010] Preferably, the middle column magnetic core comprises an upper column magnetic core and a lower column magnetic core, and the upper column magnetic core or the lower column magnetic core is detachably connected.

[0011] Preferably, the upper column magnetic core and the lower column magnetic core are connected by glue.

[0012] Preferably, screw holes are formed on both the upper column magnetic core and the lower column magnetic core, and screw rods enter the screw holes of the upper column magnetic core and the lower column magnetic core at the same time to connect the upper column magnetic core and the lower column magnetic core.

[0013] Preferably, the annular central hole surrounded by the three magnetic core components is an equilateral triangle hole.

[0014] The beneficial effects of the present invention are as follows: in this technical solution, by adopting a metal magnetic powder core and coordinating the core assembly structure, the three core assemblies are distributed in a ring, and the two adjacent middle column cores in the two core assemblies constitute a middle column core group, and a coil is set on the middle column core group. In this way, each phase coil shares the effective cross-sectional area of the two core assemblies, and the magnetic flux of the three-phase coils is balanced and the same when working, thereby adjusting the balance of the three-way magnetic circuit coupling mode, so that the accuracy of the three-way inductance can reach a difference within 3%. In this technical solution, there is only one coil for each phase inductance, avoiding the processing difficulty of the traditional coil requiring an 8-shaped surround, which can effectively reduce the product volume and weight, and reduce costs. In particular, in terms of three-phase inductance balance, because the core assemblies are distributed in a triangle, it is more reasonable than the traditional solution in terms of three-phase inductance balance, solving the important defect of the traditional three-phase inductance imbalance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly describes the drawings required for the specific embodiments or the description of the prior art. Similar elements or parts are generally identified by similar reference numerals throughout the drawings. Elements or parts in the drawings are not necessarily drawn to scale.

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0017] Figure 2 This is a schematic diagram of the overall structure of the present invention without the coil installed.

[0018] In the accompanying drawings, 1-upper cover magnetic core, 2-lower cover magnetic core, 3-middle column magnetic core, 4-coil. DETAILED DESCRIPTION

[0019] The following embodiments of the technical solution of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention and are therefore only examples and are not intended to limit the scope of protection of the present invention.

[0020] It should be noted that, unless otherwise specified, the technical or scientific terms used in this application should have the common meanings understood by those skilled in the art to which the present invention belongs.

[0021] Example 1

[0022] like Figure 1-Figure 2 As shown, this embodiment provides a balanced inductance three-phase LC harmonic filter reactor, including three magnetic core components, which are distributed in a ring shape.

[0023] The magnetic core assembly includes an upper cover magnetic core 1, a lower cover magnetic core 2 and two middle column magnetic cores 3. The top ends of the two middle column magnetic cores 3 are respectively connected to the two ends of the upper cover magnetic core 1, and the bottom ends of the two middle column magnetic cores 3 are respectively connected to the two ends of the lower cover magnetic core 2.

[0024] In the two magnetic core assemblies, two adjacent middle column magnetic cores 3 form a middle column magnetic core group, and a coil 4 is sleeved on the middle column magnetic core group.

[0025] The upper cover magnetic core 1 , the lower cover magnetic core 2 and the middle column magnetic core 3 are all metal magnetic powder cores.

[0026] In this embodiment, a metal magnetic powder core is used in combination with a magnetic core assembly structure, wherein the magnetic core assembly includes an upper cover magnetic core 1, a lower cover magnetic core 2 and two middle column magnetic cores 3. The three magnetic core assemblies are distributed in a ring. The two adjacent middle column magnetic cores 3 in the two magnetic core assemblies constitute a middle column magnetic core group. A coil 4 is set on the middle column magnetic core group. In this way, each phase coil 4 shares the effective cross-sectional area of the two magnetic core assemblies. The magnetic flux of the three-phase coil 4 is balanced and the same when working, thereby adjusting the balance of the three-way magnetic circuit coupling mode, so that the accuracy of the three-way inductance can reach a difference within 3%. The structure designed in this application has only one coil 4 for each phase inductance, avoiding the processing difficulty of the traditional coil requiring an 8-shaped surround, which can effectively reduce the product volume and weight, and reduce costs. In particular, in terms of three-phase inductance balance, because the magnetic core assemblies are distributed in a triangle, it is more reasonable than the traditional solution in terms of three-phase inductance balance, solving the important defect of the traditional three-phase inductance imbalance.

[0027] In this embodiment, the coil 4 is sleeved on the two middle column magnetic cores 3, and the magnetic circuit is integrated and coupled inside the coil.

[0028] In this embodiment, the number of turns of the three-phase coils can be exactly the same, which reduces the production process that requires a lot of man-hours to adjust the number of coil turns or fill the air gap to meet the inductance balance, saves copper material, reduces copper material cost, and reduces overall cost.

[0029] During the actual production process, a plastic skeleton can be added between the magnetic core and the coil for isolation to meet high voltage and safety creepage distance requirements.

[0030] The metal magnetic powder core in this embodiment is a sendust magnetic powder core, an iron silicon magnetic powder core, an iron nickel magnetic powder core, or a magnetic powder core formed by mixing the above three types of magnetic powder cores.

[0031] In this embodiment, the center magnetic core 3 includes an upper magnetic core and a lower magnetic core, each of which is detachably connected. This detachable connection between the upper and lower magnetic cores facilitates assembly. During use, the coil 4 is first placed over the lower magnetic core, and then the upper magnetic core is passed through the coil 4 and connected to the lower magnetic core. This allows the coil 4 to be placed over the center magnetic core, completing the assembly.

[0032] In this embodiment, the upper column magnetic core and the lower column magnetic core are connected by glue.

[0033] In this embodiment, screw holes are formed on both the upper column magnetic core and the lower column magnetic core, and screw rods enter the screw holes of the upper column magnetic core and the lower column magnetic core at the same time to connect the upper column magnetic core and the lower column magnetic core.

[0034] In this embodiment, the connection method of the middle column magnetic core 3 is selected according to different sizes. Small sizes are connected by glue, and large sizes are connected by screws.

[0035] In this embodiment, the annular central hole formed by the three magnetic core components is an equilateral triangle hole. The three magnetic core components are evenly distributed to achieve balanced three-phase inductance.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.

Claims

1. A balanced inductance three-phase LC harmonic filter reactor, characterized in that: It includes three magnetic core components, which are distributed in a ring shape. The magnetic core assembly comprises an upper cover magnetic core (1), a lower cover magnetic core (2) and two middle column magnetic cores (3), the top ends of the two middle column magnetic cores (3) are respectively connected to the two ends of the upper cover magnetic core (1), and the bottom ends of the two middle column magnetic cores (3) are respectively connected to the two ends of the lower cover magnetic core (2). In the two magnetic core assemblies, two adjacent middle column magnetic cores (3) form a middle column magnetic core group, and a coil (4) is sleeved on the middle column magnetic core group. The upper cover magnetic core (1), the lower cover magnetic core (2) and the middle column magnetic core (3) are all metal magnetic powder cores.

2. A balanced inductance three-phase LC harmonic filter reactor according to claim 1, characterized in that: The metal magnetic powder core is a sendust magnetic powder core, an iron silicon magnetic powder core, an iron nickel magnetic powder core or a magnetic powder core formed by mixing the above three types of magnetic powder cores.

3. The balanced inductance three-phase LC harmonic filter reactor according to claim 1, characterized in that: The middle column magnetic core (3) comprises an upper column magnetic core and a lower column magnetic core, and the upper column magnetic core or the lower column magnetic core is detachably connected.

4. A balanced inductance three-phase LC harmonic filter reactor according to claim 3, characterized in that: The upper column magnetic core and the lower column magnetic core are connected by glue.

5. The balanced inductance three-phase LC harmonic filter reactor according to claim 3, characterized in that: The upper column magnetic core and the lower column magnetic core are both provided with screw holes, and the screw rods enter the screw holes of the upper column magnetic core and the lower column magnetic core at the same time to connect the upper column magnetic core and the lower column magnetic core.

6. The balanced inductance three-phase LC harmonic filter reactor according to claim 1, characterized in that: The annular center hole surrounded by the three magnetic core components is an equilateral triangle hole.

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