Shielding box and shielding effectiveness detection method

Abstract

The present invention relates to the field of electromagnetic shielding technology, and in particular to a shielding box and a shielding effectiveness detection method, comprising an isolation assembly, including a sealing member, a container disposed below the sealing member, and an isolation member disposed between the sealing member and the container, the sealing member including a cover plate, the container including a box body, the box body and the cover plate are detachably connected, the isolation member including an isolation plate, the end face of the box body is provided with a first movable groove, the isolation plate is fixedly connected to the cover plate, and the isolation plate is movably matched with the first movable groove. The beneficial effect of the present invention is that by arranging an isolation member between the sealing member and the container, the shielding box can significantly reduce the risk of electromagnetic radiation leaking into the interior, so that the intensity of electromagnetic interference will be greatly attenuated, and the shielding effectiveness is significantly improved.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic shielding, in particular to a shielding box and a shielding effectiveness detection method. Background Art

[0002] The electrostatic precipitator in the power plant uses a high-frequency power supply and an integrated structural design, integrating the mainframe housing, low-voltage power distribution system, full-bridge inverter, high-frequency high-voltage transformer, control circuit, and heat dissipation system. The full-bridge inverter is arranged in front of the high-frequency transformer, the low-voltage power distribution is arranged on the side of the transformer, and the control circuit is arranged on the inside of the front door panel. The control circuit is arranged in an iron shielding box, and the box and the cover are directly overlapped and fixed with screws. Although the structure is simple, the shielding efficiency is poor, and there is a risk of radiated electromagnetic interference entering the interior through the gap between the cover and the box and affecting the control circuit.

[0003] Therefore, we proposed a shielding box and a shielding effectiveness detection method. Summary of the invention

[0004] In view of the above existing technical problems, the present invention is proposed.

[0005] The present invention aims to provide a shielding box, which aims to solve the problem of insufficient shielding effectiveness of conventional shielding boxes.

[0006] To solve the above technical problems, the present invention provides the following technical solutions: a shielding box, comprising an isolation assembly, including a sealing member, a receiving member arranged below the sealing member, and an isolation member arranged between the sealing member and the receiving member.

[0007] As a preferred solution of the shielding box of the present invention, the sealing member includes a cover plate, the containing member includes a box body, the box body and the cover plate are detachably connected, and the isolating member includes an isolating plate.

[0008] As a preferred solution of the shielding box of the present invention, wherein: a first movable groove is opened on the end surface of the box body, the isolation plate is fixedly connected to the cover plate, and the isolation plate is movably matched with the first movable groove.

[0009] As a preferred solution of the shielding box of the present invention, wherein: the cover plate is provided with a second movable groove near the end surface of the box body, the isolation plate is fixedly connected to the box body, and the isolation plate is movably matched with the second movable groove.

[0010] As a preferred solution of the shielding box of the present invention, wherein: the box body is provided with a third movable groove near the end surface of the cover plate, and the isolation plate is movably matched with the second movable groove and the third movable groove.

[0011] As a preferred solution of the shielding box of the present invention, wherein: the isolation plate includes a first isolation plate and a second isolation plate, the first movable groove includes a fourth movable groove and a fifth movable groove, the first isolation plate movably cooperates with the fourth movable groove, and the second isolation plate movably cooperates with the fifth movable groove.

[0012] As a preferred solution of the shielding box of the present invention, the isolation plate includes a third isolation plate and a fourth isolation plate arranged on the end surface of the third isolation plate, and the fourth isolation plate is made of elastic material.

[0013] As a preferred solution of the shielding box of the present invention, wherein: the first movable slot includes a sixth movable slot, a reversing slot connected to the sixth movable slot, and a seventh movable slot connected to the reversing slot.

[0014] As a preferred solution of the shielding box of the present invention, the sixth movable groove is movably matched with the third isolation plate, and the fourth isolation plate is movably matched with the reversing groove and the seventh movable groove.

[0015] The beneficial effect of the shielding box of the present invention is that by arranging an isolating member between the sealing member and the containing member, the shielding box can significantly reduce the risk of electromagnetic radiation leaking into the interior, so that the intensity of electromagnetic interference will be greatly attenuated and the shielding effectiveness will be significantly improved.

[0016] Another object of the present invention is to provide a shielding effectiveness testing method, which aims to detect the shielding effectiveness of the shielding box.

[0017] To solve the above technical problems, the present invention also provides the following technical solutions: a shielding effectiveness detection method, which includes a shielding box; and arranging an experimental site; building an experimental scene with electromagnetic interference, and adjusting various performance parameters to record the current and voltage values ​​under different isolation components; recording the current and voltage values ​​under the isolation components in different time periods and organizing the data.

[0018] The shielding effectiveness detection method of the present invention has the following beneficial effects: by conducting experimental simulation on shielding boxes of different models and types in an experimental scenario with electromagnetic interference, and statistically collating the results, the results are presented more clearly in the form of curves. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0020] Figure 1It is an overall schematic diagram of the shielding box in the present invention.

[0021] Figure 2 It is a top view of the shielding box in the present invention.

[0022] Figure 3 It is a cross-sectional view of the shielding box at AA in the present invention.

[0023] Figure 4 This is an enlarged view of the shielding box B in the present invention.

[0024] Figure 5 This is a second embodiment of the spacer of the shielding box in the present invention.

[0025] Figure 6 This is the third implementation mode of the isolation member of the shielding box in the present invention.

[0026] Figure 7 This is a fourth embodiment of the spacer of the shielding box in the present invention.

[0027] Figure 8 This is a fifth embodiment of the spacer of the shielding box in the present invention.

[0028] Fig. 9 It is a schematic diagram of the electromagnetic shielding principle in the present invention.

[0029] Fig.10 This is the magnetic field cloud diagram of the old version of the shielding box in the present invention.

[0030] Fig.11 This is the magnetic field cloud diagram of the new version of the shielding box in the present invention.

[0031] Fig.12 The figure shows the comparison of magnetic field strength between the new and old versions of the shielding box in the present invention.

[0032] Fig.13 This is the sampling curve of the old version of the shielding box in the present invention.

[0033] Fig.14 This is the sampling curve of the new version of the shielding box in the present invention. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0035] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0037] Example 1, reference Figure 1 to Figure 3 , which is the first embodiment of the present invention, provides a shielding box, including an isolation assembly 100, including a sealing member 101, a containing member 102 arranged below the sealing member 101, and an isolation member 103 arranged between the sealing member 101 and the containing member 102.

[0038] Preferably, the sealing member 101 and the containing member 102 are connected in a detachable manner such as by bolts.

[0039] Furthermore, the isolating member 103 is disposed between the sealing member 101 and the containing member 102 , and the isolating member 103 and the containing member 102 are similar in shape, that is, when the sealing member 101 and the containing member 102 are assembled, the gap between the sealing member 101 and the containing member 102 is filled by the isolating member 103 .

[0040] In the existing technology used in power plants, after the sealing member 101 and the containing member 102 of the isolation assembly 100 are overlapped and installed, the sealing member 101 and the containing member 102 are usually fixed by bolts. From a structural perspective, the structure between the sealing member 101 and the containing member 102 is relatively simple, but this direct locking by bolts, no matter what the situation, there is always a certain gap between the sealing member 101 and the containing member 102, and the electromagnetic signal penetrates through the gap, which is likely to cause damage to the circuit board inside the containing member 102.

[0041] In summary, when the sealing member 101 and the containing member 102 are installed, the isolating member 103 follows the sealing member 101 or the containing member 102 and is embedded between the sealing member 101 or the containing member 102. That is to say, the isolating member 103 is installed between the containing member 102 and the sealing member 101 like a "wedge". When there is a shielding signal outside the shielding box, the shielding signal cannot directly enter the inside of the shielding box through the gap between the sealing member 101 and the containing member 102, thereby greatly reducing the damage to the circuit inside the shielding box.

[0042] Example 2, reference Figure 4 , which is the second embodiment of the present invention, provides a shielding box, including a sealing member 101 including a cover plate 101a, a receiving member 102 including a box body 102a, the box body 102a and the cover plate 101a are detachably connected, and an isolation member 103 includes an isolation plate 103a.

[0043] A first movable groove 102b is formed on the end surface of the box body 102a, and the isolation plate 103a is fixedly connected to the cover plate 101a, and the isolation plate 103a is movably matched with the first movable groove 102b.

[0044] In this embodiment, one configuration method of the isolation plate 103a is introduced.

[0045] Preferably, a first movable groove 102b is formed on an end surface of the box body 102a close to the cover plate 101a.

[0046] Furthermore, the isolation plate 103a is made of the same material as the box body 102a and the cover plate 101a. In this embodiment, the cover plate 101a and the isolation plate 103a are fixedly connected, including integral molding, welding, etc.

[0047] In summary, during use, when installing the cover 101a, align the isolation plate 103a with the first movable groove 102b, and then directly install the isolation plate 103a into the first movable groove 102b. Then, fix the box body 102a and the cover 101a by bolts to complete the installation. The shielding signal cannot directly enter the shielding box through the gap between the box body 102a and the cover 101a, which greatly reduces the damage to the circuit inside the shielding box.

[0048] Example 3, reference Figure 5 , which is the third embodiment of the present invention, provides a shielding box, including a cover plate 101a with a second movable groove 101a-1 formed near the end surface of the box body 102a, an isolation plate 103a fixedly connected to the box body 102a, and the isolation plate 103a movably cooperates with the second movable groove 101a-1.

[0049] In this embodiment, one configuration method of the isolation plate 103a is introduced.

[0050] Contrary to the arrangement in the second embodiment, in this embodiment, the box body 102a and the isolation plate 103a are fixedly connected, including integral molding, welding, etc.

[0051] Furthermore, the isolation plate 103a is made of the same material as the box body 102a and the cover plate 101a.

[0052] In summary, when installing the cover 101a, after aligning the second movable groove 101a-1 with the isolation plate 103a, the cover 101a is directly installed in the box 102a, and then the box 102a and the cover 101a are fixed by bolts to complete the installation. The shielding signal cannot directly enter the shielding box through the gap between the box 102a and the cover 101a, which greatly reduces the damage to the circuit inside the shielding box.

[0053] Example 4, reference Figure 6 , which is the fourth embodiment of the present invention, provides a shielding box, including a box body 102a having a third movable groove 102a-1 formed on the end surface close to the cover plate 101a, and an isolation plate 103a movably cooperates with the second movable groove 101a-1 and the third movable groove 102a-1.

[0054] Preferably, the isolation plate 103a includes a side close to the box body 102a and a side away from the box body 102a. The side of the isolation plate 103a close to the box body 102a cooperates with the third movable groove 102a-1, and the side of the isolation plate 103a away from the box body 102a cooperates with the third movable groove 102a-1. At this time, it is easier to install when the width of the side of the isolation plate 103a close to the box body 102a is greater than the width of the side away from the box body 102a.

[0055] Preferably, the isolation plate 103a can also be configured to have the same shape on the side close to the box body 102a and the side away from the box body 102a, that is, Figure 6 In this case, the side of the isolation plate 103a close to the box body 102a and the side away from the box body 102a can cooperate with the two grooves, making it easier to install.

[0056] What is different from the second and third embodiments is that the isolation plate 103a is a separate part, but the isolation plate 103a is made of the same material as the box body 102a and the cover plate 101a.

[0057] In summary, before installing the cover 101a, the isolation plate 103a is matched with the third movable groove 102a-1 on the side of the box body 102a, and then the third movable groove 102a-1 on the cover 101a is matched with the side of the isolation plate 103a away from the box body 102a. Then, the box body 102a and the cover 101a are fixed by bolts to complete the installation. The shielded signal cannot directly enter the shielding box through the gap between the box body 102a and the cover 101a, which greatly reduces the damage to the circuit inside the shielding box.

[0058] Example 5, reference Figure 7 , which is the fifth embodiment of the present invention, this embodiment provides a shielding box, including an isolation plate 103a including a first isolation plate 103b and a second isolation plate 103c, the first movable groove 102b including a fourth movable groove 102c and a fifth movable groove 102d, the first isolation plate 103b and the fourth movable groove 102c are movably matched, and the second isolation plate 103c and the fifth movable groove 102d are movably matched.

[0059] Preferably, refer to Figure 7In this embodiment, similar to Embodiment 2, the isolation plate 103a is made of the same material as the box body 102a and the cover plate 101a. In this embodiment, the cover plate 101a and the isolation plate 103a are fixedly connected, including integral molding, welding, etc. Conversely, the isolation plate 103a in this embodiment can also be fixedly connected to the box body 102a as in Embodiment 3, and the movable groove is opened in the cover body 101a.

[0060] Example 6, reference Figure 8 , which is the sixth embodiment of the present invention, this embodiment provides a shielding box, including an isolation plate 103a including a third isolation plate 103d and a fourth isolation plate 103e arranged on the end surface of the third isolation plate 103d, and the fourth isolation plate 103e is made of elastic material.

[0061] Preferably, the fourth isolation plate 103e is disposed on an end surface of the third isolation plate 103d away from the cover body 101a, and the fourth isolation plate 103e is connected to the third isolation plate 103d in a fixed connection manner.

[0062] The first active groove 102b includes a sixth active groove 102e, a reversing groove 102g communicating with the sixth active groove 102e, and a seventh active groove 102f communicating with the reversing groove 102g.

[0063] The sixth movable groove 102e is movably matched with the third isolation plate 103d, and the fourth isolation plate 103e is movably matched with the reversing groove 102g and the seventh movable groove 102f.

[0064] Preferably, the sixth movable groove 102e and the seventh movable groove 102f are located in two different planes. In this embodiment, the sixth movable groove 102e and the seventh movable groove 102f are parallel to each other.

[0065] Preferably, the reversing groove 102g in this embodiment is an arc-shaped groove, which is used to connect the sixth active groove 102e and the seventh active groove 102f in two different planes.

[0066] Furthermore, the fourth isolation plate 103e is made of a material having elastic deformation capability and a certain electromagnetic isolation capability.

[0067] In summary, during installation, after aligning the fourth isolation plate 103e with the sixth active groove 102e, the first isolation plate 103e is placed in the sixth active groove 102e, and the fourth isolation plate 103e makes soft contact with the cover plate 101a along the order of the sixth active groove 102e, the reversing groove 102g, and the seventh active groove 102f, and relies on its own elastic deformation ability to make up the gap between the box body 102a and the cover plate 101a as much as possible. At the same time, the third isolation plate 103d enters the sixth active groove 102e, closes the gap between the box body 102a and the cover plate 101a in the original shielding box, and under double isolation, prevents electromagnetic signals from directly entering the box body 102a and damaging the circuit board.

[0068] Example 7, reference Figure 1 to Figure 14 , which is the second embodiment of the present invention, and this embodiment further provides a shielding effectiveness detection method.

[0069] S1 Arrange the experimental site;

[0070] Select the same model of spare equipment as the high-frequency power supply of the electrostatic precipitator actually used in the power plant to ensure the authenticity of the experimental scenario. Arrange the power board, analog board, DSP board, sampling board and other boards that are susceptible to interference when the high-frequency power supply is running in the shielding box.

[0071] S2 builds an experimental scene with electromagnetic interference and adjusts various performance parameters;

[0072] The sampled data is uploaded to the computer through the transmission line. According to the actual operation requirements, the operating parameters of the high-frequency power supply are set, and the control parameters, protection parameters, and equipment parameters are all set in accordance with the operating specifications of the power plant electrostatic precipitator.

[0073] S3 records the current and voltage values ​​under different isolation components 100;

[0074] Since the voltage and current values ​​are transmitted to the computer after sampling, and the sampling and data transmission are very susceptible to electromagnetic interference, the voltage and current waveforms are selected to reflect the shielding effectiveness of the shielding box when recording data.

[0075] S4 records the current and voltage values ​​of the isolation component 100 in different time periods and organizes the data.

[0076] Reference Fig. 9 When the incident electromagnetic wave reaches the surface of the shielding layer, due to the different impedances between the air and the shielding layer, part of the electromagnetic wave is reflected, resulting in reflection loss SE R, which is proportional to the conductivity of the shielding material. After that, the electromagnetic waves that are not reflected continue to propagate in the shielding layer. As the amplitude of the electromagnetic waves continues to change, the magnetic dipoles of the shielding material continue to polarize, converting the magnetic field energy into internal energy. At the same time, the changing magnetic field induces a changing electric field, and this process also produces energy loss, which is expressed as SE A Finally, the energy loss due to defects in the shielding material or different impedances of the shielding layer interface is recorded as SE M From the transmission line theory, it can be concluded that the shielding effectiveness SE of the shielding material is T It can be expressed as the sum of the above three losses. That is, SE T =SE R +SE A +SE M .

[0077] The shielding effectiveness of the shielding box can be expressed as the magnetic field strength H0 before using the shielding box and the magnetic field strength H after using the shielding box. S The ratio of As shown in the figure, the electric field strength E0 before using the shielding box and the electric field strength E0 after using the shielding box S The ratio of As shown. The main factors affecting the shielding effectiveness are the conductive continuity of the shielding box and the conductor passing through it. In actual engineering, a completely closed shielding box is meaningless. Therefore, holes and gaps will inevitably appear in the shielding box, which leaves room for electromagnetic leakage.

[0078] Based on the above theory, the present invention extends the gap so that the interference electromagnetic wave is continuously reflected and attenuated in the gap, thereby reducing the impact on the internal circuit. The specific structure adopts the structural form of embodiment 1 and embodiment 2 to study the shielding effectiveness of the shielding box.

[0079] Reference Fig.10 , Fig.11 This plan is formulated based on on-site reality and aims to solve problems encountered in production. It is highly targeted, simple, applicable, and requires low cost.

[0080] The use of the shielding box of the structural type in Example 1 and Example 2 can significantly reduce the risk of electromagnetic radiation leaking into the interior. A model is established in the ANSYS simulation software, and the shielding effectiveness can be intuitively seen through the magnetic field cloud map. Fig.10 and Fig.11 It can be seen that the electromagnetic signal source is emitted from the left side of the old and new version shielding boxes. Among them, the new version shielding box, that is, the structural type shielding box in Example 1 and Example 2, has a magnetic field intensity cloud map that is more biased towards blue compared to the old version shielding box, while the old version shielding box is closer to the green to yellow part.

[0081] Compare the magnetic field strength table on the left and form the relationship between the magnetic field strength and time of the two versions of shielding boxes. Fig.12 The magnetic field strength curve diagram in the figure shows that the red one is the magnetic field strength curve diagram of the old version shielding box, and the black one is the curve trend of the new version shielding box, that is, the structural type shielding box in Example 1 and Example 2. Fig.12 It can be clearly seen that the shielding effectiveness of the new shielding box, i.e., the structural type shielding box in Example 1 and Example 2, has made a qualitative leap compared to the old shielding box.

[0082] like Fig.13 , Fig.14 The figure shows the comparison of voltage and current sampling curves of two shielding boxes after actual application, among which Fig.13 For the old shielding box curve, Fig.14 This is a new version of the shielding box of the structural type in Example 1 and Example 2. The red curve in the figure is the secondary current, the blue curve is the secondary voltage, and the black curve is the input voltage. In the high-frequency power supply, the data collected by the sampling board are converted by parameter verification and setting coefficients so that they can be displayed in the same coordinate system.

[0083] It can be seen from the experimental results that although the direct overlap method of the old version of the shielding box is more accurate in sampling most of the time, it will inevitably produce waveform fluctuations or even large amplitude distortion due to magnetic leakage, which can easily cause malfunction of the protection equipment. After using the new version of the shielding box of the structural type in Example 1 and Example 2, the sampling curve tends to be stable, and the shielding effectiveness is verified.

[0084] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0085] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0086] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0087] 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 preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A shielding box, characterized in that: include, An isolation component (100) comprises a sealing member (101), a containing member (102) disposed below the sealing member (101), and an isolation member (103) disposed between the sealing member (101) and the containing member (102).

2. The shielding box according to claim 1, characterized in that: The sealing member (101) comprises a cover plate (101a), the containing member (102) comprises a box body (102a), the box body (102a) and the cover plate (101a) are detachably connected, and the isolating member (103) comprises an isolating plate (103a).

3. The shielding box according to claim 2, characterized in that: The end surface of the box body (102a) is provided with a first movable groove (102b), the isolation plate (103a) is fixedly connected to the cover plate (101a), and the isolation plate (103a) is movably matched with the first movable groove (102b).

4. The shielding box according to claim 2, characterized in that: The cover plate (101a) is provided with a second movable groove (101a-1) near the end surface of the box body (102a), the isolation plate (103a) is fixedly connected to the box body (102a), and the isolation plate (103a) is movably matched with the second movable groove (101a-1).

5. The shielding box according to claim 2, characterized in that: The box body (102a) is provided with a third movable groove (102a-1) on the end surface close to the cover plate (101a), and the isolation plate (103a) is movably matched with the second movable groove (101a-1) and the third movable groove (102a-1).

6. The shielding box according to claim 2, characterized in that: The isolation plate (103a) includes a first isolation plate (103b) and a second isolation plate (103c), the first movable groove (102b) includes a fourth movable groove (102c) and a fifth movable groove (102d), the first isolation plate (103b) is movably matched with the fourth movable groove (102c), and the second isolation plate (103c) is movably matched with the fifth movable groove (102d).

7. The shielding box according to claim 2, characterized in that: The isolation plate (103a) comprises a third isolation plate (103d) and a fourth isolation plate (103e) arranged on the end surface of the third isolation plate (103d), and the fourth isolation plate (103e) is made of elastic material.

8. The shielding box according to claim 7, characterized in that: The first active groove (102b) includes a sixth active groove (102e), a reversing groove (102g) connected to the sixth active groove (102e), and a seventh active groove (102f) connected to the reversing groove (102g).

9. The shielding box according to claim 8, characterized in that: The sixth movable groove (102e) is movably matched with the third isolation plate (103d), and the fourth isolation plate (103e) is movably matched with the reversing groove (102g) and the seventh movable groove (102f).

10. A shielding effectiveness detection method, characterized in that: A shielding box comprising any one of claims 1 to 9; and S1 Arrange the experimental site; S2 builds an experimental scene with electromagnetic interference and adjusts various performance parameters; S3 records the current and voltage values ​​under different isolation components (100); S4 records the current and voltage values ​​of the isolation component (100) in different time periods and organizes the data.

Images