CN111554467A - Vector magnet structure - Google Patents

Abstract

The present invention relates to a vector magnet structure comprising a first coil, a second coil and/or a third coil; the first coil adopts a DCT dipolar coil with a pair of pole heads arranged along the X-axis direction and is used for generating a Bx vector magnetic field distributed along the X-axis direction; the second coil adopts DCT two-pole coils with a pair of pole heads arranged along the Y-axis direction and is used for generating a By vector magnetic field distributed along the Y-axis direction, wherein the second coil is arranged outside the first coil, so that the second coil has a structure that the first coil is coated By the second coil in space; and the third coil is used for generating a Bz vector magnetic field distributed along the Z-axis direction. The method is suitable for the scientific research field with high-precision large sample vector field requirements.

Description

A vector magnet structure

technical field

The present invention relates to a magnet structure, in particular to a vector field magnet structure.

Background technique

In materials science research, multi-physics coupling analysis of material properties is a popular direction for multi-disciplinary research. With the development of science and technology, in addition to the analysis of the intrinsic mechanical and structural characteristics of materials, electromagnetic coupling analysis is an important branch. It provides a background electromagnetic field for the sample to be tested. For some materials with magnetic anisotropy, usually It is also necessary to change the angle between the sample and the direction of the magnetic field during the research process. The process is realized in the following ways: fixed-direction magnetic field + sample rotation or fixed sample + magnetic field direction rotation.

A vector magnet is a type of magnet that produces a directional rotatable magnetic field. The vector magnet realizes the rotation of the magnetic field direction by means of static ground current control rather than mechanical structure rotation, which provides many possibilities for experiments. The vector field magnet is composed of two or three pairs of dipole magnets that are not in the same direction in a three-dimensional coordinate system. As shown in Figure 1 to Figure 4, the current vector magnets on the market use dipole magnet structures. A two-pole magnet composed of a line tube pair, a racetrack coil pair, and a saddle coil pair.

圆柱样品通道的螺管型二极磁体，场质量好于±3.5％的区域球半径只有21mm，拥有相同规格样品通道的跑道型二极磁体好场区范围更小。In the combination process of the above-mentioned different types of dipole magnets, it is necessary to design a more complex skeleton to support the position distribution and assembly between the coils. The advantages are that it is easy to implement and the technology is mature. The good field area is small and the accuracy is poor, if required to have

The solenoid-type dipole magnet with the cylindrical sample channel has a spherical radius of only 21mm in the area where the field quality is better than ±3.5%, and the track-type dipole magnet with the same sample channel has a smaller field area.

SUMMARY OF THE INVENTION

In view of the above problems, the purpose of the present invention is to provide a vector field magnet structure with compact structure, large sample space, large good field area and high resolution.

In order to solve the above problems, the technical solution adopted in the present invention is: a vector magnet structure, the magnet structure includes a first coil, a second coil and/or a third coil;

The first coil adopts a pair of DCT diode coils with pole heads placed along the X-axis direction to generate a Bx vector magnetic field distributed along the X-axis direction;

The second coil adopts a pair of DCT diode coils whose pole heads are placed along the Y-axis direction to generate a By vector magnetic field distributed along the Y-axis direction, wherein the second coil is arranged outside the first coil, making it spatially present a structure in which the second coil wraps the first coil;

the third coil is used to generate a Bz vector magnetic field distributed along the Z-axis direction;

Wherein, XYZ is a Cartesian coordinate system, the Z axis is the direction of the central axis of the DCT two-pole coil, the direction of the pole head of the DCT two-pole coil is the Y-axis, and the symmetry plane between the poles of the DCT two-pole coil is perpendicular to Z The direction of the axis is the X axis.

In the above-mentioned vector magnet structure, further, the third coil is placed outside the second coil to form a vector magnet, and the spatial structure presents a coil combination sleeved on the first coil and the second coil;

Or the third coil has the same skeleton as the first coil and the second coil, and the third coil supports the first coil and the second coil in the axial direction to form a vector magnet;

Or the third coil is embedded in the first coil to form a vector magnet.

In the above-mentioned vector magnet structure, further, the third coil adopts a solenoid type magnet, a racetrack type magnet or a saddle type magnet.

The above-mentioned vector magnet structure, further, the DCT two-pole coil includes a cylindrical magnet wire surrounded by two monopole coils, and the cylindrical magnet wire is solidified on the skeleton to form a cylindrical magnet structure, and the single-pole magnet wire is formed. The pole coils are connected in series; wherein each of the monopole coils includes N turns of electromagnetic coils arranged around at intervals, wherein N is an integer, which is the total number of electromagnetic turns of the set monopole coils.

In the above-mentioned vector magnet structure, further, the current density J of the cylindrical magnet wire is approximately distributed in the circular direction with a regular distribution of cos(θ), that is, j _z =j ₀ cos(θ), where j ₀ is the pass through The current density in the cross section of the electromagnetic wire, j _z is the Z component of the equivalent current density distributed in the ring direction, and θ refers to the counterclockwise rotation angle around the Z axis with the X axis as the starting axis.

The above-mentioned vector magnet structure, further, the position distribution of the cylindrical electromagnetic wire in the circumferential direction satisfies the flow function sin(θ)=(i-1/2)/N, wherein, i is the serial number of the electromagnetic wire, which is {1 , any integer between N}.

In the above-mentioned vector magnet structure, further, the current line angle distribution θ _i =Arcsin((i-1/2)/N).

In the above-mentioned vector magnet structure, further, the coordinates of the straight side segments of each turn of the cylindrical magnet wire are (Rcos(θ _i ), Rsin(θ _i ), z), where R is the magnet wire in the polar coordinate system The radius of the distribution, the arc segment required for each turn of the cylindrical magnet wire to be continuous, and its coordinate z satisfies the flow function:

cos(π·(z-hl)/(2·he))·sin(θ)=(i-1/2)/N,

Among them, hl refers to half the length of the straight side segment, and he refers to the maximum length of the coil arc segment in the z direction.

In the above-mentioned vector magnet structure, further, the DCT diode coils can be combined in multiple layers to achieve functional enhancement requirements, that is, a plurality of coaxial DCT diode coils with different Rs are used to form a magnet with set magnetic field requirements. The layer-combined DCT diode coils can be connected in series or in parallel to be energized, or they can be energized independently, where R is the radius of the electromagnetic wire distributed in the polar coordinate system.

In the above-mentioned vector magnet structure, further, the first coil, the second coil and the third coil are all made of superconducting cables; or, the first coil, the second coil and the third coil are all made of low electrical conductivity conventional cable production.

The present invention has the following advantages due to taking the above technical solutions:

1. The present invention adopts a vector field magnet composed of Discrete Cosine Theta (DCT: discrete current cosine distribution) type coils and solenoids. The DCT two-pole coil structure can be generated in the hole area due to the spatial arrangement of the current density distributed by a trigonometric function. High-quality diode field, like the DCT-type diode coil required for the 200mm temperature hole area, the radius of the area where the field quality is better than ±3.5% can be as high as 50mm, the cylindrical structure of this type of magnet is easy to achieve multi-layer nesting To enhance the demand, it is also easy to integrate with other types of magnets, so that the vector magnet structure has the characteristics of compact structure, large sample space, large good field area and high resolution;

2. The present invention adopts superconducting technology to realize high magnetic field and three-dimensional full-space rotating magnetic field, and is applicable to the technical field requiring high-precision large sample vector field.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are for the purpose of illustrating preferred embodiments only and are not to be considered limiting of the invention. The same reference numerals are used to refer to the same parts throughout the drawings. In the attached image:

1 is a schematic diagram of a common structure of an existing vector magnet;

Fig. 2 is a schematic diagram of a ring-shaped (coil) structure magnet;

3 is a schematic diagram of a racetrack-type structure magnet;

Figures 4(a) and (b) are schematic diagrams of saddle-type magnets;

Fig. 5 is the schematic diagram that the present invention realizes the required vector magnetic field by the superposition of three sets of vector magnetic fields whose directions are perpendicular to each other;

FIG. 6 is a structure of a two-dimensional space vector magnet that can realize a plane rotating vector magnetic field, which is formed by combining the first coil and the second coil of the present invention.

FIG. 7 is a three-dimensional space vector magnet structure that can realize a three-dimensional space vector magnetic field, which is formed by combining the first coil, the second coil and the third coil of the present invention.

8 is a schematic diagram of a DCT-type structure dipole magnet of the present invention; wherein,

The reference numbers are:

1. First coil, 11. Monopolar coil, 2. Second coil, 3. Third coil.

Detailed ways

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present invention will be more thoroughly understood, and will fully convey the scope of the present invention to those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a," "an," and "the" can also be intended to include the plural forms unless the context clearly dictates otherwise. The terms "comprising", "comprising" and "having" are inclusive and thus indicate the presence of stated features, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features , steps, operations, elements, components, and/or combinations thereof. Method steps, procedures, and operations described herein are not to be construed as requiring that they be performed in the particular order described or illustrated, unless an order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be restricted by these terms. These terms may only be used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of example embodiments.

For ease of description, spatially relative terms such as "inboard", "outboard", "below" may be used herein to describe the relationship of one element or feature to another element or feature as shown in the figures ", "above", etc. This spatially relative term is intended to include different orientations of the device in use or operation other than the orientation depicted in the figures.

In this embodiment, the XYZ coordinate system can be a Cartesian right-handed coordinate system or a Cartesian left-handed coordinate system. In this embodiment, Fig. 8 is used as an example. In this embodiment, the Z-axis is defined as the direction of the central axis of the cylindrical skeleton of the DCT coil. is the direction in which the sample is placed along the length position, the direction of the pole head of the DCT diode coil is the Y axis, and the direction perpendicular to the Z axis on the symmetry plane between the DCT diode coils is the X axis. Of course, for the convenience of description, the X axis in this embodiment is , Y-axis, and Z-axis are only used as a distinguishing description of the three coordinate axes, and should not be limited by the above names in actual use, and the names of each coordinate axis can be defined according to actual needs.

As shown in FIGS. 5 to 7 , the vector magnet structure provided in this embodiment includes a first coil 1 , a second coil 2 and/or a third coil 3 .

The first coil 1 adopts a pair of DCT two-pole coils with pole heads placed along the X-axis direction, which are located at the innermost side of the vector magnet structure to generate a Bx vector magnetic field distributed along the X-axis direction, wherein the pole heads are multi-pole magnet magnetic lines of force For a certain spatial position of the gathering, for example, the pole heads of a solenoid-type two-pole magnet are the geometric center areas of the two solenoids, and the pole heads of a DCT diode coil are the area surrounded by the innermost current loop.

The second coil 2 adopts a pair of DCT diode coils with pole heads placed along the Y-axis direction, and is arranged outside the first coil 1. The second coil 2 is in the form of wrapping the first coil 1, and is used to generate a distribution along the Y-axis direction. By vector magnetic field.

The third coil 3 adopts one or more conventional coils to generate a vector magnetic field distributed along the Z-axis direction in the aperture area of the magnet; following the principle of compact structure, it can be arranged outside the second coil 2 (the space structure is set on the first coil). 1 and the coil combination of the second coil 2), or the same skeleton with the first coil 1 and the second coil 2 (the two coil structures of the third coil in the Z direction support the first coil 1 and the second coil 2), Or embedded in the first coil Bx to generate a Bz vector magnetic field distributed along the Z-axis direction; preferably, the third coil 3 can be a ring-type (solenoid), racetrack-type, saddle-type magnet or other types of magnets , as long as a constant-direction magnetic field with a certain spatial distribution and field quality can be generated in the temperature hole region, the above three groups of coils together form a three-dimensional vector magnet structure.

In some embodiments of the present invention, the first coil 1 , the second coil 2 and the third coil 3 can be combined in pairs to realize a two-dimensional plane vector field magnet. For example, the combination of the first coil 1 and the second coil 2 can be obtained in XY In addition, the first coil 1, the second coil 2 and the third coil 3 can also be composed of a vector magnet that is a three-dimensional three-dimensional vector magnet, and a three-dimensional vector magnetic field distribution similar to a cuboid distribution can be obtained in the inner hole space. .

In some embodiments of the present invention, both the first coil 1 and the second coil 2 adopt a DCT diode coil structure, and generally, the magnetic field directions of the two coils are perpendicular to each other.

As shown in FIG. 8 , the DCT two-pole coil structure includes two monopole coils 11 surrounded by a cylindrical magnet wire, wherein the cylindrical magnet wire is solidified on a cylindrical skeleton to form a cylindrical magnet structure, and the monopole coils 11 are connected in series with each other connected, each monopole coil 11 includes N turns of electromagnetic coils arranged around at intervals, wherein, N is a positive integer, which refers to the total number of electromagnetic wire turns of the set monopole coil 11, and the distribution of the cylindrical electromagnetic wire is easy to realize different DCTs. The nesting of the diode coils is easy to achieve performance enhancement or combined function design, that is, multiple coaxial DCT diode coils with different R can be used to combine to form a magnet with set magnetic field requirements, and the multi-layer combined DCT diode coil can be It can be connected in series or parallel to power on, and can also be powered on independently, where R is the radius of the electromagnetic wire distributed in the polar coordinate system.

The DCT coil structure approximately realizes the cos( _mθ ) distribution requirement of the current density in the form of discrete current line positions. _z = j ₀ cos(θ), where j ₀ is the current density passing through the cross-section of the magnet wire, j _z is the Z component of the equivalent current density distributed in the hoop direction, and is the actual current required by a pure 2m-pole magnetic field. m means that the coil is composed of 2m monopoles. When m=1, a dipole magnetic field can be designed with a high uniformity distribution in the space surrounded by the electromagnetic line (gap), that is, the DCT dipole coil is obtained, and θ means X The axis is the starting axis, the angle of counterclockwise rotation around the Z axis. The position distribution of the cylindrical magnet wire in the circumferential direction (referring to the direction of θ growth) satisfies the flow function sin(mθ)=(i-1/2)/N, where i is the serial number of the magnet wire, which is between {1, N} Any integer of ; θ is the position angle corresponding to the ith turn of the electromagnetic wire. The current line angle distribution θ _i =Arcsin((i-1/2)/N)/m required for the 2m-pole magnetic field can be obtained through the flow function.

Therefore, the coordinates of the straight side segment of each turn of the cylindrical magnet wire are (Rcos(mθ _i ), Rsin(mθ _i ), z), and R is the distribution radius of the magnet wire in polar coordinates; each turn of the cylindrical magnet wire is continuous The required arc segment whose coordinate z satisfies the flow function: cos(π·(z-hl)/(2·he))·sin(mθ)=(i-1/2)/N, to correct the non-infinite coil Therefore, the overall integral field quality of the magnet is the best. Among them, hl refers to half the length of the straight side segment; he refers to the maximum length of the coil arc segment in the z direction; the position of the arc segment electromagnetic line can be set differently according to requirements. Flow functions, such as the uniform spacing distribution of adjacent turns (the spacing between adjacent turns is always consistent) or the equal spacing distribution at the farthest end of the arc, etc. (only the turn spacing at the farthest end of the arc is controlled to ensure the best turn density without inter-turn space interference). Of course, parameters such as layer turns, operating current, maximum magnetic field, and coil length of the coil of the DCT diode coil structure are specifically designed according to the physical requirements of the user. As shown in Figure 6, the layer turns of the DCT diode coil N=40, the current density J ₀ =594A/mm ² , skeleton radius R=100mm, good field magnetic field By=0.5T, magnet length L=500.

In some embodiments of the present invention, the first coil 1, the second coil 2 and the third coil 3 are separately powered, and the user can control the power supply to obtain the vector magnetic field of the required size and direction according to the manual data of the test calibration, or use the sensor The required magnetic field is obtained by closed-loop feedback adjustment. As shown in Figure 6, it is a two-dimensional XY plane vector magnet composed of the first coil 1 and the second coil 2 arranged perpendicular to each other. = 150A current, the central area of the temperature hole can generate a vector magnetic field of (0.5T, 0T, 0T). 0T) vector magnetic field, then when the vector magnetic field of (0.5T, 0.5T, 0T) needs to be generated in the central area of the thermowell, it is only necessary to pass the current of I=150A to the first coil 1 and the second coil 2 at the same time. This is an example, you can choose according to your needs.

In some embodiments of the present invention, the magnet wires of the first coil 1, the second coil 2 and the third coil 3 can be made of conventional conductive wires with low electrical conductivity such as copper and aluminum, or can also be made of NbTi, Nb ₃ Sn, etc. Made of superconducting cables.

In some embodiments of the present invention, the first coil 1 , the second coil 2 and the third coil 3 may share the same support frame, or they may be independent of each other, and finally assembled into a vector magnet. The specific structure of the support frame is not limited. The corresponding structure is adopted according to the actual situation.

In some embodiments of the present invention, the included angles of the magnetic field directions of the three groups of coils may also be non-vertical, so as to adapt to magnets with special magnetic field requirements, which can be determined according to actual requirements.

The above-mentioned embodiments are only used to illustrate the present invention, and the structure, connection method and manufacturing process of each component can be changed to some extent. Any equivalent transformation and improvement based on the technical solution of the present invention should not be used. Excluded from the scope of protection of the present invention.

Claims (10)

1. A vector magnet arrangement, characterized in that the magnet arrangement comprises a first coil, a second coil and/or a third coil;

the first coil adopts a DCT dipolar coil with a pair of pole heads arranged along the X-axis direction and is used for generating a Bx vector magnetic field distributed along the X-axis direction;

the second coil adopts DCT two-pole coils with a pair of pole heads arranged along the Y-axis direction and is used for generating a By vector magnetic field distributed along the Y-axis direction, wherein the second coil is arranged outside the first coil, so that the second coil has a structure that the first coil is coated By the second coil in space;

the third coil is used for generating a Bz vector magnetic field distributed along the Z-axis direction;

the X-axis and the Y-axis are respectively a first axis and a second axis, wherein XYZ is a Cartesian coordinate system, the Z axis is the central axis direction of the DCT dipolar coil, the polar head direction of the DCT dipolar coil is the Y axis, and the direction perpendicular to the Z axis on the inter-polar symmetric plane of the DCT dipolar coil is the X axis.

2. The vector magnet structure according to claim 1, wherein the third coil is placed outside the second coil to constitute a vector magnet, and the spatial structure presents a combination of coils nested in the first and second coils;

or the third coil, the first coil and the second coil are in the same framework, and the third coil axially holds the first coil and the second coil to form a vector magnet;

or the third coil is embedded in the first coil to form a vector magnet.

3. The vector magnet structure of claim 2, wherein the third coil is a solenoid type magnet, a racetrack type magnet, or a saddle type magnet.

4. The vector magnet structure of claim 1, wherein said DCT dipole coils comprise cylinder-shaped magnet wires surrounded by two monopole coils, said cylinder-shaped magnet wires being consolidated on a former to form a cylinder-shaped magnet structure, said monopole coils being connected in series; each unipolar coil comprises N circles of electromagnetic coils which are arranged in a surrounding mode at intervals, wherein N is an integer and is the set total number of electromagnetic wire turns of the unipolar coil.

5. The vector magnet structure of claim 4, wherein the current density J of the cylindrical magnet wires is approximately in a regular cos (θ) distribution in the circumferential direction, i.e., J_z＝j₀cos (θ), wherein j₀For passing the current density in the cross-section of the magnet wire, j_zIs an equivalent current density Z component distributed annularlyThe quantity θ refers to the angle of counterclockwise rotation about the Z axis starting from the X axis.

6. The vector magnet structure according to claim 5, wherein the circumferential position distribution of the cylinder-type magnet wires satisfies a flow function sin (θ) ═ i-1/2)/N, where i is a magnet wire number and is any integer between {1, N }.

7. The vector magnet structure according to claim 6, wherein the current line angular distribution θ_i＝Arcsin((i-1/2)/N)。

8. The vector magnet structure of claim 7, wherein the barrel magnet wire turns have straight segment coordinates of (Rcos (θ))_i)，Rsin(θ_i) Z), wherein R is the radius of the magnet wire distributed in the polar coordinate system, and the coordinate z of the arc segment required by each turn of the cylindrical magnet wire satisfies the flow function:

cos(π·(z-hl)/(2·he))·sin(θ)＝(i-1/2)/N，

where hl refers to half the length of the straight segment and he refers to the maximum length of the coil arc segment in the z-direction.

9. The vector magnet structure according to claim 1, wherein the DCT dipolar coil can be combined in a multi-layer nested manner to meet the requirement of function enhancement, that is, a plurality of coaxial DCT dipolar coils with different R are combined to form a magnet with the requirement of a set magnetic field, and the multi-layer DCT dipolar coil can be powered in series or in parallel or independently, wherein R is the radius of the electromagnetic wire distributed in the polar coordinate system.

10. The vector magnet structure according to any of claims 1 to 9, wherein the first, second and third coils are all made of superconducting cables;

alternatively, the first coil, the second coil and the third coil are all made of conventional cables with low electric conductivity.

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