An oriented silicon steel magnetic shielding device and demagnetization system

Abstract

This invention provides a magnetic shielding device and demagnetizing system for grain-oriented silicon steel. It can fully utilize the high permeability of grain-oriented silicon steel along the easy magnetization axis to achieve a low-cost, high-shielding magnetic shielding device. The silicon steel laying method is changed according to the magnetic field characteristics of the construction site environment to achieve the best shielding effect. The demagnetizing coil is wound according to the laying method of the grain-oriented silicon steel, thereby effectively demagnetizing grain-oriented silicon steel laid in different directions. Moreover, the demagnetizing coils in different circulation directions are independent of each other and do not affect the shielding layer in other laying directions, which can improve the demagnetizing efficiency and quality.

Description

Technical Field

[0001] This invention belongs to the field of magnetic field protection and shielding technology, and particularly relates to an oriented silicon steel magnetic shielding device and demagnetization system. Background Technology

[0002] Magnetic shielding devices can effectively shield external magnetic fields and create a very weak magnetic environment with very low magnetic field strength inside the space. With the development of paleomagnetism, biomagnetism, space science and basic physics and other fields, the demand for clean magnetic environments has increased. In recent years, the requirements for the shielding performance, construction cost and durability of magnetic field shielding devices have also been continuously improved.

[0003] Existing shielded rooms primarily utilize hexahedral enclosed spaces constructed from soft magnetic materials with high permeability, forming multi-layered passive shielding that blocks external magnetic fields through magnetic field diversion. Commonly used soft magnetic shielding materials are permalloy and silicon steel. Permalloy has high permeability, which is beneficial for improving shielding effectiveness, but it is expensive; ordinary silicon steel is inexpensive but has lower permeability; while high-permeability oriented silicon steel combines the advantages of price and high permeability, making it increasingly popular in the market. The characteristic of oriented silicon steel is that almost all grains have crystal planes parallel to the rolling plane and crystal orientations parallel to the rolling direction. This results in its easy magnetization axis being parallel to the rolling direction, with high permeability in the rolling direction and low permeability in the transverse and normal directions. Consequently, the shielding effectiveness in the rolling orientation direction is significantly superior compared to that in the transverse and normal directions.

[0004] The existing construction processes for permalloy and silicon steel shielding rooms cannot fully utilize the advantages of grain-oriented silicon steel, and may even produce the opposite effect. Furthermore, due to the orientation of its easily magnetized axis, the existing shielding room demagnetization system cannot effectively demagnetize grain-oriented silicon steel. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a magnetic shielding device and demagnetization system for oriented silicon steel. By utilizing the high magnetic permeability of oriented silicon steel in the rolling direction, it achieves high magnetic field shielding effectiveness and reduces the construction cost of shielding rooms.

[0006] A magnetic shielding device for oriented silicon steel, wherein the shielding device is a hexahedral enclosed space, and the hexahedral enclosed space can be divided into three mutually perpendicular circulation directions along the circumferential side. Among them, the four sides in the horizontal direction form a side ring as the horizontal circulation direction, the four sides parallel to the horizontal component of the ambient magnetic field are the vertical circulation direction, and the other is the main circulation direction. The construction site of the shielding device is divided into ideal mode and non-ideal mode.

[0007] In the ideal mode, the long side of the shielding device is perpendicular to the horizontal component of the ambient magnetic field, and the short side is parallel to the horizontal component of the ambient magnetic field. At this time, the surface of the shielding device including the long side is also covered with an oriented silicon steel shielding layer along the main circulation direction, and a demagnetizing coil is also wound on the surface covered with the oriented silicon steel shielding layer.

[0008] In the non-ideal mode, the long side of the shielding device is not perpendicular to the horizontal component of the ambient magnetic field, or the short side is not parallel to the horizontal component of the ambient magnetic field. In this case, the surface of the shielding device that is parallel to the horizontal component of the ambient magnetic field is also covered with an oriented silicon steel shielding layer along the main circulation direction, and a demagnetizing coil is also wound on the surface covered with the oriented silicon steel shielding layer.

[0009] Furthermore, for a oriented silicon steel magnetic shielding device, it is also necessary to determine how to lay the oriented silicon steel shielding layer based on the magnetic inclination angle at the latitude of the location where the shielding device is built, the magnitude of the horizontal component and the vertical component of the environmental magnetic field.

[0010] In the ideal scenario, if the shielding device is located in a low-latitude region and the horizontal component of the ambient magnetic field is greater than the vertical component, the shielding device will lay an oriented silicon steel shielding layer on the surface including the long side along the main circulation direction, and also lay oriented silicon steel shielding layers on the four sides in the horizontal circulation direction. If the shielding device is located in a high-latitude region and the horizontal component of the ambient magnetic field is less than the vertical component, the shielding device will lay an oriented silicon steel shielding layer on the surface including the long side along the main circulation direction, and also lay oriented silicon steel shielding layers on the four sides in the vertical circulation direction. Furthermore, a demagnetizing coil is wound on the surface where the oriented silicon steel shielding layer is laid, wherein the demagnetizing coil in the vertical circulation direction is parallel to the horizontal component of the ambient magnetic field.

[0011] Furthermore, for a oriented silicon steel magnetic shielding device, it is also necessary to determine how to lay the oriented silicon steel shielding layer based on the magnitude of the magnetic inclination angle at the latitude of the location where the shielding device is constructed and the magnitude of the horizontal and vertical components of the environmental magnetic field.

[0012] In a non-ideal mode, if the shielding device is located in a low-latitude region and the horizontal component of the ambient magnetic field is greater than the vertical component, in addition to the surface parallel to the horizontal component of the ambient magnetic field along the main circulation direction, the shielding device also has oriented silicon steel shielding layers laid on the four sides in the horizontal circulation direction. If the shielding device is located in a high-latitude region and the horizontal component of the ambient magnetic field is less than the vertical component, in addition to the surface parallel to the horizontal component of the ambient magnetic field along the main circulation direction, the shielding device also has oriented silicon steel shielding layers laid on the four sides in the vertical circulation direction. Furthermore, the surface with the oriented silicon steel shielding layer is also wound with a demagnetizing coil, wherein the demagnetizing coil in the horizontal circulation direction is perpendicular to the horizontal component of the ambient magnetic field.

[0013] Furthermore, the low-latitude region refers to the spatial range of the Earth's surface with a magnetic inclination of less than 45 degrees between the north and south latitudes, while the high-latitude region refers to the area of ​​the Earth's surface with a magnetic inclination of greater than 45 degrees between the North and South Poles.

[0014] A demagnetizing system for a magnetic shielding device for oriented silicon steel includes a magnetic field measurement module, a programmable demagnetizing power supply module, and a demagnetizing coil module;

[0015] The magnetic field measurement module is placed inside the shielding device to detect the deterioration of the residual magnetic field level caused by the magnetization of the shielding layer, providing a reference for whether demagnetization is needed and the effect after demagnetization.

[0016] The programmable demagnetizing power supply module is used to input the demagnetizing current required for demagnetizing into the demagnetizing coil module; wherein, the demagnetizing current is a continuously or intermittently applied sine wave, and the current amplitude gradually decreases with time, and demagnetizing ends when the current amplitude decreases to zero;

[0017] The demagnetizing coil module includes multiple demagnetizing coils uniformly wound on an oriented silicon steel shielding layer, used to convert the demagnetizing current into a magnetic field.

[0018] Furthermore, the demagnetizing coil module is divided into a main demagnetizing coil, a horizontal demagnetizing coil, and a vertical demagnetizing coil according to the different winding positions;

[0019] The main demagnetizing coil, horizontal demagnetizing coil, and vertical demagnetizing coil operate independently, demagnetizing only the easy magnetization axis direction of the oriented silicon steel shielding layer in the main circulation direction, horizontal circulation direction, and vertical circulation direction, respectively, without affecting the silicon steel shielding layer in other circulation directions.

[0020] Beneficial effects:

[0021] 1. This invention provides a magnetic shielding device for oriented silicon steel, which can fully utilize the high permeability of highly magnetically oriented silicon steel in the direction of easy magnetization axis to achieve a low-cost, high-shielding magnetic shielding device; according to the magnetic field characteristics of the construction site environment, the silicon steel laying method is changed to achieve the best shielding effect; demagnetizing coils are wound according to the laying method of oriented silicon steel, thereby effectively demagnetizing oriented silicon steel laid in different directions, and the demagnetizing coils in different circulation directions are independent of each other and do not affect the shielding layer in other laying directions, thus improving demagnetizing efficiency and quality.

[0022] 2. This invention provides a magnetic shielding device for oriented silicon steel, which sets the appropriate oriented silicon steel laying method according to different latitudes and environmental magnetic fields, thereby achieving optimal material utilization and shielding effectiveness.

[0023] 3. This invention provides a demagnetization system that utilizes the high magnetic permeability of oriented silicon steel in the rolling direction to achieve high magnetic field shielding efficiency, reduce the construction cost of the shielding room, and change the silicon steel laying method according to the magnetic field characteristics of the construction site to achieve the best shielding effect; and winds the demagnetization coil according to the laying method of oriented silicon steel to improve demagnetization efficiency and quality. Attached Figure Description

[0024] Figure 1 A schematic diagram of the shielding layer laid in the main circulation and horizontal circulation directions provided by the present invention;

[0025] Figure 2 A schematic diagram of the shielding layer laid in the main circulation and vertical circulation directions provided by the present invention;

[0026] Figure 3 Schematic diagram of the main circulation and horizontal circulation demagnetizing coils provided for this invention;

[0027] Figure 4 Schematic diagram of the main circulation and vertical circulation demagnetizing coils provided by the present invention;

[0028] Figure 5 Flowchart of the design of the oriented silicon steel magnetic shielding device provided by the present invention;

[0029] Figure 6 A schematic diagram of the demagnetization system for a magnetic shielding device for oriented silicon steel provided by the present invention;

[0030] Figure 7 The magnetic field distribution diagram provided by this invention during the operation of the main circulation coil;

[0031] Figure 8 The magnetic field distribution diagrams provided by this invention for the main circulation and horizontal circulation demagnetizing coils during operation. Detailed Implementation

[0032] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0033] like Figure 1 and Figure 2 As shown, an oriented silicon steel magnetic shielding device is a hexahedral closed space. The hexahedral closed space can be divided into three mutually perpendicular circulation directions along the circumferential side. Among them, the four sides in the horizontal direction form the side ring, which is the horizontal circulation direction. The four sides parallel to the horizontal component of the ambient magnetic field are the vertical circulation direction, and the other is the main circulation direction. The construction site of the shielding device is divided into ideal mode and non-ideal mode.

[0034] In the ideal mode, the long side of the shielding device is perpendicular to the horizontal component of the ambient magnetic field, and the short side is parallel to the horizontal component of the ambient magnetic field. At this time, the surface of the shielding device including the long side is also covered with an oriented silicon steel shielding layer along the main circulation direction, and a demagnetizing coil is also wound on the surface covered with the oriented silicon steel shielding layer.

[0035] In the non-ideal mode, the long side of the shielding device is not perpendicular to the horizontal component of the ambient magnetic field, or the short side is not parallel to the horizontal component of the ambient magnetic field. In this case, the surface of the shielding device that is parallel to the horizontal component of the ambient magnetic field is also covered with an oriented silicon steel shielding layer along the main circulation direction, and a demagnetizing coil is also wound on the surface covered with the oriented silicon steel shielding layer.

[0036] In other words, when the orientation design of the shielded room is limited by the construction environment and cannot meet the requirement that the long side of the shielding device is perpendicular to the horizontal component of the ambient magnetic field and the short side is parallel to the horizontal component of the ambient magnetic field, the main circulation oriented silicon steel shielding layer must be laid in the direction parallel to the horizontal component of the ambient magnetic field.

[0037] Furthermore, the present invention also needs to determine how to lay the oriented silicon steel shielding layer based on the magnetic inclination angle at the latitude of the location where the shielding device is constructed, the magnitude of the horizontal component and the vertical component of the environmental magnetic field;

[0038] In the ideal scenario, if the shielding device is located in a low-latitude region and the horizontal component of the ambient magnetic field is greater than the vertical component, the shielding device, in addition to laying an oriented silicon steel shielding layer on the surface including the long side along the main circulation direction, also lays oriented silicon steel shielding layers on the four sides in the horizontal circulation direction. If the shielding device is located in a high-latitude region and the horizontal component of the ambient magnetic field is less than the vertical component, the shielding device, in addition to laying an oriented silicon steel shielding layer on the surface including the long side along the main circulation direction, also lays oriented silicon steel shielding layers on the four sides in the vertical circulation direction. Furthermore, a demagnetizing coil is wound on the surface where the oriented silicon steel shielding layer is laid, wherein the demagnetizing coil in the vertical circulation direction is parallel to the horizontal component of the ambient magnetic field. Figure 3 As shown.

[0039] In a non-ideal mode, if the shielding device is located in a low-latitude region and the horizontal component of the ambient magnetic field is greater than the vertical component, the shielding device has an oriented silicon steel shielding layer laid on the surface parallel to the horizontal component of the ambient magnetic field along the main circulation direction, and also has oriented silicon steel shielding layers laid on the four sides in the horizontal circulation direction. If the shielding device is located in a high-latitude region and the horizontal component of the ambient magnetic field is less than the vertical component, the shielding device has an oriented silicon steel shielding layer laid on the surface parallel to the horizontal component of the ambient magnetic field along the main circulation direction, and also has oriented silicon steel shielding layers laid on the four sides in the vertical circulation direction. Furthermore, a demagnetizing coil is wound on the surface with the oriented silicon steel shielding layer, wherein the demagnetizing coil in the horizontal circulation direction is perpendicular to the horizontal component of the ambient magnetic field. Figure 4 As shown.

[0040] It should be noted that the low-latitude regions refer to the spatial range between the north and south latitude magnetic inclination angles of the Earth's surface of less than 45 degrees, while the high-latitude regions refer to the area between the north and south latitude magnetic inclination angles of the Earth's surface of greater than 45 degrees and the North and South Poles. Generally speaking, the horizontal component of the environmental magnetic field in low-latitude regions is greater than the vertical component, while the horizontal component is less than the vertical component in high-latitude regions. However, both low-latitude and high-latitude regions can have local geomagnetic anomalies. For example, in some local areas of low latitudes, the vertical component is greater than the horizontal component, and in some local areas of high latitudes, the vertical component is less than the horizontal component. For these local geomagnetic anomaly areas, it is necessary to compare the actual measured vertical and horizontal components of the geomagnetic field, and then determine how to lay the oriented silicon steel shielding layer based on the comparison results.

[0041] Therefore, it can be seen that, Figure 5 As shown, the oriented silicon steel magnetic shielding device provided by this invention includes the following main design steps: S1, oriented construction of the shielding device. Specifically, before construction, the ambient magnetic field of the construction site can be measured. The long side of the shielding room is designed to be perpendicular to the horizontal component of the ambient magnetic field (north-south direction), generally in the east-west direction, and the short side is parallel to the horizontal component of the ambient magnetic field (north-south direction), generally in the north-south direction; S2, oriented laying of the silicon steel shielding layer. The laying method of the shielding layer is changed according to the latitude of the construction site or the magnitude of the horizontal and vertical components of the ambient magnetic field; S3, oriented arrangement of the demagnetizing coil. The demagnetizing coil is wound according to the oriented laying method of the shielding layer. Specifically, when the silicon steel shielding layer is laid in the main circulation direction and the horizontal circulation direction, the main demagnetizing coil and the horizontal demagnetizing coil are wound accordingly for demagnetization; when the silicon steel shielding layer is laid in the main circulation direction and the vertical circulation direction, the main demagnetizing coil and the vertical demagnetizing coil are wound accordingly for demagnetization.

[0042] Furthermore, such as Figure 6As shown, the present invention also provides a demagnetization system for a magnetic shielding device for oriented silicon steel, including a magnetic field measurement module 510, a programmable demagnetization power supply module 520, and a demagnetization coil module 530.

[0043] The magnetic field measurement module 510 is placed inside the shielding device to detect the deterioration of the residual magnetic field level caused by the magnetization of the shielding layer, providing a reference for whether demagnetization is needed and the effect after demagnetization.

[0044] The programmable demagnetizing power supply module 520 is used to input the demagnetizing current required for demagnetizing into the demagnetizing coil module; wherein, the demagnetizing current is a continuously or intermittently applied sine wave, and the current amplitude gradually decreases with time, and demagnetizing ends when the current amplitude decreases to zero;

[0045] The demagnetizing coil module 530 includes a plurality of demagnetizing coils uniformly wound on an oriented silicon steel shielding layer, used to convert the demagnetizing current into a magnetic field.

[0046] Meanwhile, the demagnetizing coil module is divided into a main demagnetizing coil, a horizontal demagnetizing coil, and a vertical demagnetizing coil according to the different winding positions. The main demagnetizing coil, the horizontal demagnetizing coil, and the vertical demagnetizing coil work independently, and demagnetize only the easy magnetization axis direction of the oriented silicon steel shielding layer in the main circulation direction, the horizontal circulation direction, and the vertical circulation direction, respectively, without affecting the silicon steel shielding layer in other circulation directions.

[0047] Furthermore, this invention utilizes Ansys Electronics Desktop finite element analysis software to model and simulate the demagnetizing coil and shielding layer. The simulation results when the main circulation coil operates alone are as follows: Figure 7 As shown, the magnetic field generated on the main circulation shielding layer is uniformly distributed and has little impact on the shielding layers in other circulation directions. Simulation results of the main circulation coil and the horizontal circulation coil operating simultaneously are shown below. Figure 8 As shown, the magnetic field generated on the shielding layer in the corresponding cyclic direction is uniformly distributed and has little mutual influence.

[0048] In summary, this invention provides a magnetic shielding device for oriented silicon steel, which aims to utilize the high magnetic permeability of oriented silicon steel in the rolling direction to achieve high magnetic field shielding efficiency, reduce the construction cost of the shielding room, and achieve the best shielding effect by changing the silicon steel laying method according to the magnetic field characteristics of the construction site environment; and improve the demagnetizing efficiency and quality by winding demagnetizing coils according to the laying method of oriented silicon steel.

[0049] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A magnetic shielding device for oriented silicon steel, characterized in that, The shielding device is a hexahedral enclosed space. The hexahedral enclosed space can be divided into three mutually perpendicular circulation directions along the circumferential side. Among them, the four sides in the horizontal direction form the side ring, which is the horizontal circulation direction. The four sides parallel to the horizontal component of the ambient magnetic field are the vertical circulation direction, and the other is the main circulation direction. The construction site of the shielding device is divided into ideal mode and non-ideal mode. In the ideal mode, the long side of the shielding device is perpendicular to the horizontal component of the ambient magnetic field, and the short side is parallel to the horizontal component of the ambient magnetic field. At this time, the surface of the shielding device including the long side is also covered with an oriented silicon steel shielding layer along the main circulation direction, and a demagnetizing coil is also wound on the surface covered with the oriented silicon steel shielding layer. In the non-ideal mode, the long side of the shielding device is not perpendicular to the horizontal component of the ambient magnetic field, or the short side is not parallel to the horizontal component of the ambient magnetic field. In this case, the surface of the shielding device that is parallel to the horizontal component of the ambient magnetic field is also covered with an oriented silicon steel shielding layer along the main circulation direction, and a demagnetizing coil is also wound on the surface covered with the oriented silicon steel shielding layer.

2. The grain-oriented silicon steel magnetic shielding device as described in claim 1, characterized in that, It is also necessary to determine how to lay the oriented silicon steel shielding layer based on the magnetic inclination angle at the latitude of the location where the shielding device is built, as well as the magnitude of the horizontal and vertical components of the ambient magnetic field. In the ideal scenario, if the shielding device is located in a low-latitude region and the horizontal component of the ambient magnetic field is greater than the vertical component, the shielding device will lay an oriented silicon steel shielding layer on the surface including the long side along the main circulation direction, and also lay oriented silicon steel shielding layers on the four sides in the horizontal circulation direction. If the shielding device is located in a high-latitude region and the horizontal component of the ambient magnetic field is less than the vertical component, the shielding device will lay an oriented silicon steel shielding layer on the surface including the long side along the main circulation direction, and also lay oriented silicon steel shielding layers on the four sides in the vertical circulation direction. Furthermore, a demagnetizing coil is wound on the surface where the oriented silicon steel shielding layer is laid, wherein the demagnetizing coil in the vertical circulation direction is parallel to the horizontal component of the ambient magnetic field.

3. The grain-oriented silicon steel magnetic shielding device as described in claim 1, characterized in that, It is also necessary to determine how to lay the oriented silicon steel shielding layer based on the magnetic inclination angle at the latitude of the location where the shielding device is built and the magnitude of the horizontal and vertical components of the environmental magnetic field. In a non-ideal mode, if the shielding device is located in a low-latitude region and the horizontal component of the ambient magnetic field is greater than the vertical component, in addition to laying an oriented silicon steel shielding layer on the surface parallel to the horizontal component of the ambient magnetic field along the main circulation direction, an oriented silicon steel shielding layer is also laid on the four sides in the horizontal circulation direction. If the shielding device is located in a high-latitude region and the horizontal component of the ambient magnetic field is less than the vertical component, in addition to laying an oriented silicon steel shielding layer on the surface parallel to the horizontal component of the ambient magnetic field along the main circulation direction, an oriented silicon steel shielding layer is also laid on the four sides in the vertical circulation direction. Furthermore, a demagnetizing coil is wound on the surface where the oriented silicon steel shielding layer is laid. The demagnetizing coil in the horizontal circulation direction is perpendicular to the horizontal component of the ambient magnetic field.

4. A grain-oriented silicon steel magnetic shielding device as described in claim 2 or 3, characterized in that, The low-latitude region refers to the spatial range of the Earth's surface with a magnetic inclination of less than 45 degrees between the north and south latitudes, while the high-latitude region refers to the area of ​​the Earth's surface with a magnetic inclination of greater than 45 degrees between the North and South Poles.

5. A demagnetizing system for the oriented silicon steel magnetic shielding device according to claim 1, characterized in that, Includes a magnetic field measurement module, a programmable demagnetizing power supply module, and a demagnetizing coil module; The magnetic field measurement module is placed inside the shielding device to detect the deterioration of the residual magnetic field level caused by the magnetization of the shielding layer, providing a reference for whether demagnetization is needed and the effect after demagnetization. The programmable demagnetizing power supply module is used to input the demagnetizing current required for demagnetizing into the demagnetizing coil module; wherein, the demagnetizing current is a continuously or intermittently applied sine wave, and the current amplitude gradually decreases with time, and demagnetizing ends when the current amplitude decreases to zero; The demagnetizing coil module includes multiple demagnetizing coils uniformly wound on an oriented silicon steel shielding layer, used to convert the demagnetizing current into a magnetic field.

6. A demagnetizing system for the oriented silicon steel magnetic shielding device of claim 1 as described in claim 5, characterized in that, The demagnetizing coil module is divided into main demagnetizing coil, horizontal demagnetizing coil and vertical demagnetizing coil according to the different winding positions; The main demagnetizing coil, horizontal demagnetizing coil, and vertical demagnetizing coil operate independently, demagnetizing only the easy magnetization axis direction of the oriented silicon steel shielding layer in the main circulation direction, horizontal circulation direction, and vertical circulation direction, respectively, without affecting the silicon steel shielding layer in other circulation directions.

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