Processing method of clamp plate type magnetic shielding structure and clamp plate type magnetic shielding structure

Abstract

The present invention provides a processing method of a clamp plate type magnetic shielding structure and a clamp plate type magnetic shielding structure. The processing method of the clamp plate type magnetic shielding structure comprises: step S1: determining the radial width dimension, radial length dimension and axial height dimension of a silicon steel sheet group, using a high magnetic permeability material and processing and stacking a plurality of silicon steel sheets according to the radial width dimension, radial length dimension and axial height dimension to form a silicon steel sheet group; step S2: processing a frame; step S3: surrounding the outer circumference of the silicon steel sheet group with insulating paper; step S4: sleeve the frame on the silicon steel sheet group surrounded by the insulating paper, so as to tighten and / or bond the insulating paper, the silicon steel sheet group and the frame by a binding tape, thereby forming a clamp plate type magnetic shielding structure. The present invention effectively solves the problem that the manufacturing process of the magnetic shielding structure in the prior art is complicated and easy to cause insulation quality accidents.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and in particular to a processing method of a clamping plate type magnetic shielding structure and a clamping plate type magnetic shielding structure. Background Art

[0002] At present, the leakage magnetic field of large-capacity power transformers (500MVA and above) is relatively strong. The strong leakage magnetic field will inevitably intersect with the metal structural parts of the power transformer, which will bring at least two consequences to the running products: first, the clamps inside the product will induce large eddy current losses, which are prone to local overheating and endanger the safe operation of the product; second, the eddy current losses on the clamps are an important part of the load losses. Large eddy current losses will lead to large load losses of the product, and the product operation is not energy-efficient.

[0003] In order to solve the above problems, in the prior art, a lung-lobe type magnetic shielding structure is usually used to shield leakage magnetic flux. Although this structure can reduce eddy current losses on the transformer clamps to reduce load losses, its manufacturing process is very complicated, the manufacturing cycle is long and the manufacturing cost is high, and the requirements for manufacturing and installation accuracy are very strict (the allowable deviation is usually not more than ±3mm). In addition, since the lung-lobe magnetic shielding is built into the pressure plate at the end of the coil, it is in a high field strength area, which can easily cause insulation quality accidents. Summary of the invention

[0004] The main purpose of the present invention is to provide a processing method of a clamp plate type magnetic shielding structure and a clamp plate type magnetic shielding structure to solve the problem that the manufacturing process of the magnetic shielding structure in the prior art is complicated and easily causes insulation quality accidents.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a processing method of a clamp plate type magnetic shielding structure is provided, comprising: step S1: determining the radial width dimension, radial length dimension and axial height dimension of a silicon steel sheet group, using a high magnetic permeability material and processing and stacking a plurality of silicon steel sheets according to the radial width dimension, radial length dimension and axial height dimension to form a silicon steel sheet group; step S2: processing a frame; step S3: surrounding the outer peripheral surface of the silicon steel sheet group with insulating paper; step S4: sleeve the frame on the silicon steel sheet group surrounded by the insulating paper, so as to tighten and / or bond the insulating paper, the silicon steel sheet group and the frame by means of binding tape, thereby forming a clamp plate type magnetic shielding structure.

[0006] Furthermore, in step S1, the method for determining the radial width dimension of the silicon steel sheet group includes: using simulation software and setting boundary conditions of preset parameters to obtain the leakage flux density of the clamp plate type magnetic shielding structure, so as to determine the axial height dimension of the silicon steel sheet group according to the error range between the leakage flux density and the preset leakage flux density.

[0007] Furthermore, in step S1, the method for determining the axial height dimension of the silicon steel sheet group includes: when the transformer is in maximum operating condition, calculating the maximum magnetic leakage of the transformer according to the physical positions of the high-voltage coil and the medium-voltage coil, so as to determine the radial width dimension according to the maximum magnetic leakage.

[0008] Further, in step S1, the method for determining the radial length size of the silicon steel sheet group includes: obtaining the length L1 of the radial edge of the high-voltage coil and the length L2 of the radial edge of the medium-voltage coil of the transformer; if L1≥L2, along the radial length direction of the silicon steel sheet group, both sides of the silicon steel sheet group protrude from the radial edge of the high-voltage coil and the radial length of the protruding part is greater than or equal to 0.15L1; if L2>L1, along the radial length direction of the silicon steel sheet group, both sides of the silicon steel sheet group protrude from the radial edge of the medium-voltage coil and the radial length of the protruding part is greater than or equal to 0.15L2.

[0009] Further, in step S2, the method for processing the frame includes: setting an opening on the short side of the frame, the opening penetrating the frame along the height direction of the frame; and / or, rounding the corners of the frame; and / or, opening a grounding hole on the frame.

[0010] Furthermore, in step S4, after the frame is sleeved on the silicon steel sheet group surrounded by the insulating paper, the processing method of the clip plate type magnetic shielding structure further includes: arranging an insulating structure in the opening.

[0011] According to another aspect of the present invention, there is provided a clamp plate type magnetic shielding structure, which is manufactured by the above-mentioned processing method of the clamp plate type magnetic shielding structure, and the clamp plate type magnetic shielding structure comprises: a silicon steel sheet group, comprising a plurality of silicon steel sheets stacked in sequence along the height direction of the clamp plate type magnetic shielding structure; a frame having an opening and surrounding the outside of the silicon steel sheet group; and insulating paper arranged between the frame and the silicon steel sheet group.

[0012] Furthermore, the clamp plate type magnetic shielding structure also includes: a binding strap, which is bound on the frame and the silicon steel sheet group; wherein, there are multiple binding straps, and the multiple binding straps are spaced apart along the length direction of the frame.

[0013] Furthermore, two adjacent silicon steel sheets are bonded to each other; and / or, the silicon steel sheet group and the insulating paper are bonded to each other; and / or, the insulating paper and the frame are bonded to each other.

[0014] Furthermore, the frame has two connecting sections arranged opposite to each other, an opening is formed between the two connecting sections, and each connecting section has a through hole; the clamp plate type magnetic shielding structure also includes: an insulating plate, arranged in the opening; a fastener, the fastener is passed through the through holes of the two connecting sections to connect the two connecting sections; an insulating tube, which is sleeved outside the fastener and located between the through hole and the fastener.

[0015] Applying the technical solution of the present invention, the processing method of the clamp plate type magnetic shielding structure is: first determine the radial width dimension, radial length dimension and axial height dimension of the silicon steel sheet group, use high magnetic permeability material and process and stack multiple silicon steel sheets according to the radial width dimension, radial length dimension and axial height dimension to form a silicon steel sheet group; then process the frame; then, surround the outer peripheral surface of the silicon steel sheet group with insulating paper; finally, sleeve the frame on the silicon steel sheet group surrounded by the insulating paper, so as to tighten and / or bond the insulating paper, silicon steel sheet group and the frame by binding tape, thereby forming a clamp plate type magnetic shielding structure. In this way, the clamp plate type magnetic shielding structure is obtained by the above processing method, which not only reduces the processing complexity of the magnetic shielding structure, but also has the same energy-saving effect as the lobe magnetic shielding structure, and its manufacturing process is relatively simple, and the manufacturing cycle and manufacturing cost are only about one-fourth of the lobe magnetic shielding structure in the prior art, which is highly practical and economical, thereby solving the problem that the manufacturing process of the magnetic shielding structure in the prior art is complicated and easy to cause insulation quality accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 A flow chart showing an embodiment of a method for processing a clamp plate type magnetic shielding structure according to the present invention;

[0018] Figure 2 It shows a front view of the clamp plate type magnetic shielding structure according to the present invention;

[0019] Figure 3 Shows Figure 1 An enlarged schematic diagram of the clamp plate type magnetic shielding structure at point A;

[0020] Figure 4 Shows Figure 1 Side view of the clip-on plate type magnetic shielding structure.

[0021] The above drawings include the following reference numerals:

[0022] 10. Silicon steel sheet group; 11. Silicon steel sheet;

[0023] 20. frame; 21. opening; 22. connecting section;

[0024] 30. Insulation paper;

[0025] 40. Binding straps;

[0026] 50. Insulation board;

[0027] 60. Fasteners. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0030] In the present invention, unless otherwise specified, the directional words used, such as "up" and "down", usually refer to the directions shown in the drawings, or to the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "left" and "right" usually refer to the left and right shown in the drawings; "inside" and "outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit the present invention.

[0031] In order to solve the problem in the prior art that the manufacturing process of the magnetic shielding structure is complicated and easily causes insulation quality accidents, the present application provides a processing method of a clamp plate type magnetic shielding structure and a clamp plate type magnetic shielding structure.

[0032] like Figure 1 As shown, the processing method of the clamp plate type magnetic shielding structure includes:

[0033] Step S1: determining the radial width, radial length and axial height of the silicon steel sheet group, using a high magnetic permeability material and processing and stacking a plurality of silicon steel sheets according to the radial width, radial length and axial height to form a silicon steel sheet group;

[0034] Step S2: processing the frame;

[0035] Step S3: placing insulating paper around the outer circumference of the silicon steel sheet group;

[0036] Step S4: sleeve the frame onto the silicon steel sheet group surrounded by the insulating paper, and use a binding tape to tightly bind and / or bond the insulating paper, the silicon steel sheet group and the frame, thereby forming a clip plate type magnetic shielding structure.

[0037] By applying the technical solution of this embodiment, a clamp-plate type magnetic shielding structure is produced through the above-mentioned processing method, which not only reduces the processing complexity of the magnetic shielding structure, but also has the same energy-saving effect as the lobe magnetic shielding structure. Its manufacturing process is relatively simple, and its manufacturing cycle and manufacturing cost are only about one-fourth of the lobe magnetic shielding structure in the prior art. It has strong practicality and good economy, thereby solving the problem that the manufacturing process of the magnetic shielding structure in the prior art is complicated and easy to cause insulation quality accidents.

[0038] In this embodiment, a circle of insulating paper is formed around the silicon steel sheet group to insulate the frame and the silicon steel sheet group, which can effectively prevent the frame from being short-circuited through the ends of the silicon steel sheet group to form a short-circuit ring, thereby avoiding local overheating.

[0039] In this embodiment, a plurality of silicon steel sheets are bonded together using high temperature resistant glue and tied with binding tape, which can ensure the clamping degree of the frame and the silicon steel sheet group and reduce noise.

[0040] In this embodiment, in step S1, the method for determining the radial width dimension of the silicon steel sheet group includes:

[0041] The simulation software is used and boundary conditions of preset parameters are set to obtain the leakage flux density of the clamp plate type magnetic shielding structure, so as to determine the axial height dimension of the silicon steel sheet group according to the error range between the leakage flux density and the preset leakage flux density.

[0042] Specifically, the preset parameters include the number of turns and phase current of the coil.

[0043] In this embodiment, in step S1, the method for determining the axial height dimension of the silicon steel sheet group includes:

[0044] When the transformer is in the maximum operating condition, the maximum magnetic leakage of the transformer is calculated according to the physical positions of the high-voltage coil and the medium-voltage coil, so as to determine the radial width size according to the maximum magnetic leakage.

[0045] It should be noted that the axial height dimension of the silicon steel sheet group is the stacking thickness of multiple silicon steel sheets.

[0046] In this embodiment, in step S1, the method for determining the radial length dimension of the silicon steel sheet group includes:

[0047] Obtain the length L1 of the radial edge of the high-voltage coil and the length L2 of the radial edge of the medium-voltage coil of the transformer;

[0048] If L1≥L2, along the radial length direction of the silicon steel sheet group, both sides of the silicon steel sheet group protrude from the radial edge of the high-voltage coil and the radial length of the protruding part is greater than or equal to 0.15L1;

[0049] If L2>L1, along the radial length direction of the silicon steel sheet group, both sides of the silicon steel sheet group protrude from the radial edge of the medium voltage coil and the radial length of the protruding part is greater than or equal to 0.15L2.

[0050] In this embodiment, in step S2, the method for processing the frame includes:

[0051] An opening is provided on the short side of the frame, and the opening penetrates the frame along the height direction of the frame; and / or,

[0052] Rounding the corners of the border; and / or,

[0053] A grounding hole is provided on the frame.

[0054] Specifically, the temperature of the frame is lower than the maximum temperature rise requirement of the metal structure. The frame is made of low-magnetic material. The above opening can effectively avoid the formation of circulating current, reduce eddy current loss, and avoid local overheating. Among them, the rounded corners are greater than or equal to R8mm to reduce the surface field strength of the frame and avoid insulation breakdown. At the same time, the above setting of the grounding hole achieves reliable grounding and avoids the occurrence of floating potential to ensure the insulation reliability of the product during operation.

[0055] In this embodiment, in step S4, after the frame is sleeved on the silicon steel sheet group surrounded by the insulating paper, the processing method of the clip plate type magnetic shielding structure further includes: arranging an insulating structure in the opening.

[0056] Specifically, the above-mentioned arrangement of the insulating structure can prevent the frame from being short-circuited through the end of the silicon steel sheet, thereby preventing the formation of a short-circuit ring and preventing the occurrence of local overheating.

[0057] In this embodiment, the simulation software is finite element software, and the magnetic field finite element analysis follows Maxwell's equations. The calculation adopts a three-dimensional model of the transformer. The Maxwell's equations are as follows:

[0058]

[0059]

[0060]

[0061]

[0062] Where D is the electric displacement vector, in C / m; J is the current density vector, in A / m 2 ; B is the magnetic induction intensity vector, unit is T; E is the electric field intensity vector, unit is V / m; H is the magnetic field intensity vector, unit is A / m; ρ is the charge density, unit is C / m 3 .

[0063] Specifically, the constitutive equation for electromagnetic calculation is:

[0064] D=εE (Formula 5)

[0065] B=μH (Formula 6)

[0066] J = σE (Formula 7)

[0067] Among them, ε is the dielectric constant of the medium, the unit is F / m; μ is the magnetic permeability of the medium, the unit is H / m; σ is the electrical conductivity of the medium, the unit is S / m.

[0068] The specific method is:

[0069] 1. Determine the electromagnetic design parameters of the transformer and establish the corresponding three-dimensional model;

[0070] 2. Set the material properties, excitation conditions and boundary conditions of the electromagnetic calculation module;

[0071] 3. The electromagnetic material parameters of different materials are mainly set as magnetic permeability and electrical conductivity. The core of the transformer is a nonlinear ferromagnetic material;

[0072] 4. The boundary condition is the default magnetic field calculation boundary where the magnetic field lines are parallel to the air parcel.

[0073] Specifically, after the finite element method is used to calculate the losses in the transformer, the calculation results are coupled to the temperature field calculation module according to the grid unit by unit, and a three-dimensional temperature-fluid multi-physics coupling field is established based on the finite element analysis method software with this as the heat source to accurately simulate the transformer convection heat transfer process and realize the transformer component temperature rise calculation and winding hot spot prediction. Among them, the fluid-temperature field calculation adopts the convection heat dissipation calculation model and the heat conduction model. The overall temperature inside the liquid-immersed transformer is low, and the influence of thermal radiation on heat dissipation can be ignored.

[0074] like Figures 2 to 4 As shown, the present application also provides a clamp plate type magnetic shielding structure, which is manufactured by the above-mentioned processing method of the clamp plate type magnetic shielding structure, and the clamp plate type magnetic shielding structure includes a silicon steel sheet group 10, a frame 20 and an insulating paper 30. Among them, the silicon steel sheet group 10 includes a plurality of silicon steel sheets 11 stacked in sequence along the height direction of the clamp plate type magnetic shielding structure, and the frame 20 has an opening 21 and surrounds the outside of the silicon steel sheet group 10. The insulating paper 30 is arranged between the frame 20 and the silicon steel sheet group 10. Specifically, the clamp plate type magnetic shielding structure manufactured by the above-mentioned processing method not only reduces the processing complexity of the magnetic shielding structure, but also has the same energy-saving effect as the lobe magnetic shielding structure. Its manufacturing process is relatively simple, and the manufacturing cycle and manufacturing cost are only about one-fourth of the lobe magnetic shielding structure in the prior art. It is highly practical and economical, thereby solving the problem that the manufacturing process of the magnetic shielding structure in the prior art is complicated and easy to cause insulation quality accidents.

[0075] like Figure 2 and Figure 4 As shown, the clamp plate type magnetic shielding structure further includes a binding band 40, which is bound on the frame 20 and the silicon steel sheet group 10. There are multiple binding bands 40, and the multiple binding bands 40 are spaced apart along the length direction of the frame 20. In this way, the above arrangement improves the binding stability and reliability of the binding bands 40.

[0076] Optionally, two adjacent silicon steel sheets 11 are bonded together; and / or, the silicon steel sheet group 10 and the insulating paper 30 are bonded together; and / or, the insulating paper 30 and the frame 20 are bonded together. In this way, the above arrangement further improves the overall structural stability of the clip plate type magnetic shielding structure.

[0077] like Figure 2 and Figure 3 As shown, the frame 20 has two connecting sections 22 arranged opposite to each other, an opening 21 is formed between the two connecting sections 22, and each connecting section 22 has a through hole. The clamp plate type magnetic shielding structure also includes an insulating plate 50, a fastener 60 and an insulating cylinder. Among them, the insulating plate 50 is arranged in the opening 21, and the fastener 60 is passed through the through holes of the two connecting sections 22 to connect the two connecting sections 22. The insulating cylinder is sleeved outside the fastener 60 and is located between the through hole and the fastener 60. In this way, the above-mentioned arrangement of the insulating plate 50 and the insulating cylinder

[0078] In this embodiment, grounding sheets are inserted into the silicon steel sheets before bonding, so that the silicon steel sheet group can be reliably grounded.

[0079] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0080] The processing method of the clamp plate type magnetic shielding structure is: first determine the radial width dimension, radial length dimension and axial height dimension of the silicon steel sheet group, use high magnetic permeability material and process and stack multiple silicon steel sheets according to the radial width dimension, radial length dimension and axial height dimension to form a silicon steel sheet group; then process the frame; then, surround the outer peripheral surface of the silicon steel sheet group with insulating paper; finally, sleeve the frame on the silicon steel sheet group surrounded by the insulating paper, and tighten and / or bond the insulating paper, silicon steel sheet group and the frame by binding tape, thereby forming a clamp plate type magnetic shielding structure. In this way, the clamp plate type magnetic shielding structure is obtained by the above processing method, which not only reduces the processing complexity of the magnetic shielding structure, but also has the same energy-saving effect as the lobe magnetic shielding structure. Its manufacturing process is relatively simple, and the manufacturing cycle and manufacturing cost are only about one-fourth of the lobe magnetic shielding structure in the prior art. It is highly practical and economical, thereby solving the problem that the manufacturing process of the magnetic shielding structure in the prior art is complicated and easy to cause insulation quality accidents.

[0081] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0082] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0083] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for processing a clamp plate type magnetic shielding structure, characterized in that: include: Step S1: determining the radial width dimension, radial length dimension and axial height dimension of the silicon steel sheet group, using a high magnetic permeability material and processing and stacking a plurality of silicon steel sheets according to the radial width dimension, the radial length dimension and the axial height dimension to form the silicon steel sheet group; Step S2: processing the frame; Step S3: placing insulating paper around the outer circumference of the silicon steel sheet group; Step S4: sleeve the frame onto the silicon steel sheet group surrounding the insulating paper, and bind and / or bond the insulating paper, the silicon steel sheet group and the frame by means of a binding tape, thereby forming a clip plate type magnetic shielding structure; In step S1, the method for determining the radial length dimension of the silicon steel sheet group includes: Obtain the length L1 of the radial edge of the high-voltage coil and the length L2 of the radial edge of the medium-voltage coil of the transformer; If L1≥L2, along the radial length direction of the silicon steel sheet group, both sides of the silicon steel sheet group protrude from the radial edge of the high-voltage coil and the radial length of the protruding part is greater than or equal to 0.15L1; If L2>L1, along the radial length direction of the silicon steel sheet group, both sides of the silicon steel sheet group protrude from the radial edge of the medium voltage coil and the radial length of the protruding part is greater than or equal to 0.15L2.

2. The processing method of the clamp plate type magnetic shielding structure according to claim 1, characterized in that: In step S1, the method for determining the radial width dimension of the silicon steel sheet group includes: The simulation software is used and boundary conditions of preset parameters are set to obtain the leakage flux density of the clamp plate type magnetic shielding structure, so as to determine the axial height dimension of the silicon steel sheet group according to the error range between the leakage flux density and the preset leakage flux density.

3. The processing method of the clamp plate type magnetic shielding structure according to claim 1, characterized in that: In step S1, the method for determining the axial height dimension of the silicon steel sheet group includes: When the transformer is in the maximum operating condition, the maximum magnetic leakage of the transformer is calculated according to the physical positions of the high-voltage coil and the medium-voltage coil, so as to determine the radial width size according to the maximum magnetic leakage.

4. The processing method of the clamp plate type magnetic shielding structure according to claim 1, characterized in that: In step S2, the method for processing the frame includes: An opening is provided on the short side of the frame, and the opening penetrates the frame along the height direction of the frame; and / or, Rounding the corners of the frame; and / or, A grounding hole is provided on the frame.

5. The processing method of the clamp plate type magnetic shielding structure according to claim 4, characterized in that: In the step S4, after the frame is sleeved on the silicon steel sheet group surrounding the insulating paper, the processing method of the clip plate type magnetic shielding structure further includes: An insulating structure is disposed within the opening.

6. A clamp plate type magnetic shielding structure, characterized in that: The clamp plate type magnetic shielding structure is manufactured by the processing method of any one of claims 1 to 5, and the clamp plate type magnetic shielding structure comprises: A silicon steel sheet group (10) comprising a plurality of silicon steel sheets (11) stacked in sequence along a height direction of the clamping plate type magnetic shielding structure; A frame (20) having an opening (21) and surrounding the silicon steel sheet group (10); Insulating paper (30) is arranged between the frame (20) and the silicon steel sheet group (10).

7. The clip plate type magnetic shielding structure according to claim 6, characterized in that: The clamp plate type magnetic shielding structure also includes: A binding belt (40) is bound on the frame (20) and the silicon steel sheet group (10); There are a plurality of binding straps (40), and the plurality of binding straps (40) are arranged at intervals along the length direction of the frame (20).

8. The clip plate type magnetic shielding structure according to claim 6, characterized in that: Two adjacent silicon steel sheets (11) are bonded to each other; and / or the silicon steel sheet group (10) and the insulating paper (30) are bonded to each other; and / or the insulating paper (30) and the frame (20) are bonded to each other.

9. The clip plate type magnetic shielding structure according to claim 6, characterized in that: The frame (20) has two connecting sections (22) arranged opposite to each other, the opening (21) is formed between the two connecting sections (22), and each connecting section (22) has a through hole; The clamp plate type magnetic shielding structure also includes: An insulating plate (50) disposed in the opening (21); A fastener (60), wherein the fastener (60) is passed through the through holes of the two connecting sections (22) to connect the two connecting sections (22); An insulating cylinder is sleeved outside the fastener (60) and is located between the through hole and the fastener (60).

Images