Nonlinear impact magnet based on nanocrystalline magnetic material and matched power supply system

Abstract

The invention belongs to the technical field of particle accelerators, and discloses a nonlinear impact magnet based on a nanocrystalline magnetic material and a matched power supply system. The nonlinear impact magnet comprises a magnetic core and a magnet exciting coil assembly, the magnetic core comprises magnetic poles and a magnetic yoke; the magnetic pole and the magnet yoke are both of a fully-symmetrical annular structure, and the magnet yoke is arranged on the periphery of the magnetic pole. The magnetic pole comprises N same magnetic pole units, N is 4, 6 or 8, and the magnetic pole is made by laminating nanocrystalline strips; and the excitation coil assembly is wound outside each magnetic pole unit. Compared with a traditional silicon steel sheet or ferrite magnetic core, the magnet provided by the invention can improve the uniformity of a magnetic field, and the magnetic pole made of the nanocrystalline strip with ultrahigh magnetic conductivity and low coercive force has stronger magnetic field uniformity and low disturbance characteristic; and the design requirement of the STCF clash ring off-axis injection system for low disturbance of the circulating beam bunch can be better met.

Description

Technical Field

[0001] This invention belongs to the field of particle accelerator technology, and more specifically, relates to a nonlinear impact magnet based on nanocrystalline magnetic materials and a matching power supply system. Background Technology

[0002] In synchrotron radiation sources or electron-positron colliders, the layout of the injection system is crucial, directly affecting beam injection efficiency and the long-term stability of the apparatus. Furthermore, fourth-generation synchrotron radiation sources and high-energy colliders generally employ small dynamic apertures and highly focusing structures, making traditional injection methods unsuitable. Therefore, novel injection layouts and designs are necessary. To ensure high average luminosity in the collision zone and the stability of the machine itself, a top-up injection mode will be used. The beam intensity in the ring must be precisely replenished through high-frequency injection operations to ensure that the beam charge remains stable during long-term operation.

[0003] The traditional approach for impact magnets used in synchrotron radiation sources or electron-positron colliders is as follows: (1) Traditional impact magnets are mostly made of ferrite or silicon steel sheets, such as the common C-type or H-type impact magnets. The excitation coil is wound on the iron core, and a magnetic field is generated by pulsed current. (2) The injection method is mostly convex rail injection, that is, the pulsed magnetic field generated by multiple impact magnets causes the beam track to deflect in a "convex rail". This approach requires a large dynamic aperture. The disadvantages of this traditional injection approach are: the pulse response is lagging, the silicon steel core has large eddy current losses under high frequency pulses, which cannot meet the fast response requirements of narrow pulses for new generation colliders such as STCF, and the traditional convex rail injection is difficult to meet the requirements of small dynamic aperture restrictions, which causes large disturbance to the circulating beam and has low injection efficiency.

[0004] To achieve low-emittance beam injection, an injection device capable of effectively reducing beam disturbance is needed. Magnets, as key components controlling beam trajectory, are crucial for achieving low beam disturbance in off-axis injection. Traditional impact magnets often use core materials such as ordinary ferrite or partially metallic cores, which exhibit significant limitations in permeability and hysteresis characteristics when faced with rapidly changing pulsed magnetic fields. During off-axis injection, the permeability of these materials undergoes nonlinear changes during the rapid rise and fall phases of the pulsed magnetic field, leading to magnetic field waveform distortion. This makes it impossible to adequately meet the specific requirements of STCF off-axis injection for magnetic field uniformity and low disturbance. Therefore, there is an urgent need to design a novel nonlinear impact magnet to address this problem. Summary of the Invention

[0005] In view of the above-mentioned defects or improvement needs of the existing technology, the present invention provides a nonlinear impact magnet based on nanocrystalline magnetic materials, which aims to solve the design requirements of low disturbance of circulating bundles in the off-axis injection system of synchrotron radiation source or electron-positron collider.

[0006] To achieve the objectives of this invention, according to a first aspect of the invention, a nonlinear impact magnet based on nanocrystalline magnetic materials is provided, comprising: a magnetic core and an excitation coil assembly; the magnetic core includes magnetic poles and a magnetic yoke;

[0007] Both the magnetic pole and the magnetic yoke are fully symmetrical ring structures, and the magnetic yoke is located on the periphery of the magnetic pole; the magnetic pole contains N identical magnetic pole units, where N is 4, 6 or 8, and the magnetic pole is made by stacking nanocrystalline ribbon; the excitation coil assembly is wound around the magnetic pole body of each magnetic pole unit.

[0008] As a preferred embodiment of the present invention, the nanocrystalline ribbon is selected from one of iron-based nanocrystalline alloys, nickel-based nanocrystalline alloys, cobalt-based nanocrystalline alloys, aluminum-based nanocrystalline alloys, or magnesium-based nanocrystalline alloys; wherein, the iron-based nanocrystalline alloys include Finemet-type iron-based nanocrystalline alloys or Nanoperm-type iron-based nanocrystalline alloys.

[0009] The Finemet-type iron-based nanocrystalline alloy preferably contains Fe. 73.5 Si 13.5 B9Nb3Cu1, the Nanoperm-type iron-based nanocrystalline alloy preferably contains Fe. 84 Zr7B8Cu1, the nickel-based nanocrystal composite is preferably Ni 81 Fe 17 Mo2, the aluminum-based nanocrystalline alloy preferably Al 85 Ni 10 Y5, the magnesium-based nanocrystalline alloy is preferably Mg 97 Zn1Ca2.

[0010] As a preferred embodiment of the present invention, each magnetic pole unit comprises a magnetic pole head and a magnetic pole body, wherein the magnetic pole head is the portion of the magnetic pole unit located near the center of the annular structure, and the magnetic pole body is the portion located between the magnetic pole head and the magnetic yoke;

[0011] The magnetic pole head has a gradually changing arc structure; the magnetic pole body has a stepped structure with the contour gradually receding from the magnetic yoke to the magnetic pole head.

[0012] As a preferred embodiment of the present invention, the magnetic pole comprises a fully symmetrical ring structure composed of eight identical magnetic pole units.

[0013] As a preferred embodiment of the present invention, the magnetic yoke is made of pure iron or DT4.

[0014] As a preferred embodiment of the present invention, the excitation coil assembly is a copper wire wound around the outside of each magnetic pole body.

[0015] As a preferred embodiment of the present invention, the excitation coil assembly is an oxygen-free copper enameled wire winding wound along the outer contour of the magnetic pole body; or, the excitation coil assembly has insulating support units between layers and at the edges of the side coils.

[0016] As a preferred embodiment of the present invention, the excitation coil assembly further includes a cooling system unit, which is embedded along the contour of the magnetic pole body.

[0017] According to a second aspect of the present invention, a nonlinear impact magnet and a matching power supply system are provided, comprising a nonlinear impact magnet based on nanocrystalline magnetic material and an excitation power supply as described above, wherein the excitation coil lead of the nonlinear impact magnet based on nanocrystalline magnetic material is connected to the output terminal of the excitation power supply via a terminal block.

[0018] As a preferred embodiment of the present invention, the excitation power supply adopts 2 / N power supplies connected in parallel synchronously.

[0019] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages:

[0020] 1. The nonlinear impact magnet provided by this invention has magnetic poles made of nanocrystalline ribbon, and the nanocrystalline magnetic poles have ultra-high permeability (initial permeability can reach 10). 4 -10 5 With a high flux density (on the order of magnitude) and low coercivity (<1 A / m), the magnetic core exhibits extremely fast response speed (on the order of nanoseconds) under narrow pulse currents in the microsecond range, precisely tracking current changes. This rapid response characteristic allows the magnet to control the deflection of the particle beam in a timely and accurate manner during off-axis injection. Simultaneously, the fully symmetrical ring structure formed by the combination of nanocrystalline magnetic poles and the yoke utilizes the principle of magnetic field superposition to compensate for magnetic fields at different locations, significantly improving magnetic field uniformity. Furthermore, this structure enhances overall structural stability; under the electromagnetic force of high-frequency pulses, the components experience balanced stress and minimal deformation, effectively reducing magnetic field disturbances caused by structural vibrations. More importantly, compared to traditional silicon steel sheets or ferrite cores, the loss characteristics of the core based on nanocrystalline magnetic materials are significantly improved in high-frequency environments. Silicon steel sheets suffer from a sharp increase in losses due to eddy current effects at high frequencies, while ferrites have the problem of large hysteresis losses. However, nanocrystalline materials, through grain refinement and composition optimization, can reduce losses by 50%-70% at frequencies of kHz and above. This significantly reduces the temperature rise of the magnetic core, and the rate of magnetic performance degradation is much slower than that of traditional magnetic cores during long-term operation. This can stably meet the stringent design requirements of low disturbance of circulating bundles for the off-axis injection system of the next-generation synchrotron radiation source and electron-positron collider.

[0021] 2. The magnetic poles of this invention preferably comprise a fully symmetrical ring structure consisting of eight identical magnetic pole units. Firstly, the fully symmetrical ring structure ensures a highly symmetrical distribution of the magnetic field in both the radial and circumferential directions. The magnetic pole units are uniformly arranged within the ring space. According to the principle of magnetic field superposition, the magnetic fields generated by adjacent magnetic poles complement and cancel each other out within the ring region, thus forming a more uniform magnetic field in the target area. The magnetic field distribution of the octagonal structure is dominated by eighth-order symmetry terms. Through the reverse superposition of the eight magnetic poles, low-order interference components such as quadrupoles and hexapoles can be canceled out. Quadrupole and hexapole structures inevitably introduce strong higher-order components into their magnetic field distribution, while the octagonal structure exhibits stronger magnetic field uniformity. Secondly, traditional asymmetrical magnetic pole structures tend to generate strong stray magnetic fields outside the magnet during operation. These stray magnetic fields can interfere with surrounding electronic equipment and other magnetic field components, thus affecting the transmission of the particle beam. In the fully symmetrical ring structure, the magnetic fields generated by the magnetic poles are mutually constrained within the ring, and the external stray magnetic fields cancel each other out due to symmetry, significantly reducing the intensity of the stray magnetic field. Third, the eight magnetic pole units are evenly distributed on the ring frame, ensuring uniform stress distribution and effectively resisting deformation caused by electromagnetic forces during operation. Compared to the structural deformation problems that easily occur in traditional asymmetrical structures due to uneven stress distribution, this structure can maintain geometric stability over a long period, thus ensuring long-term stability of magnetic field performance. Furthermore, the symmetrical structure is easier to assemble and debug, and the parameter consistency of each magnetic pole unit is easier to control, reducing production and maintenance costs.

[0022] 3. The trapezoidal winding method employed in this invention allows the coil to closely conform to the magnetic pole contour. By designing a turn count gradient that is wider at the bottom and narrower at the top, the coil can completely fill the magnetic pole slots, avoiding the space waste caused by mismatch between the coil and the magnetic pole slots in traditional winding methods. This optimized design allows for a 15%-20% increase in the number of coil turns under the same magnetic pole volume. According to Ampere's circuital law, magnetic field strength is proportional to the number of turns, thus effectively increasing the magnetic field strength. Conversely, while meeting the same magnetic field strength requirements, the core volume can be significantly reduced, making the magnet structure more compact and saving installation space, especially suitable for off-axis injection systems with strict size limitations. Simultaneously, the close-fitting winding method also reduces the gap between the coil and the magnetic poles, lowers the leakage flux coefficient, improves the utilization efficiency of the magnetic field, and further enhances the magnet's performance. Attached Figure Description

[0023] Figure 1 This is a schematic cross-sectional view of a nonlinear impact magnet based on nanocrystalline magnetic materials, as exemplified in this invention.

[0024] Figure 2 This is a diagram illustrating the trapezoidal coil winding structure of a nonlinear impact magnet based on nanocrystalline magnetic materials, as exemplified by this invention.

[0025] Figure 3This is a diagram showing the connection of four parallel power supply coils for an octet-type nonlinear impact magnet, as exemplified by this invention.

[0026] Figure 4 This is a schematic diagram of the magnetic field distribution generated in a plane in an octet-type nonlinear impact magnet, as exemplified by this invention.

[0027] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0028] 1-Magnetic yoke; 2-Magnetic pole body; 3-Magnetic pole head; 4-Excitation coil assembly. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0030] This invention provides a nonlinear impact magnet based on nanocrystalline magnetic materials, which is used in electron-positron collision rings or off-axis injection systems of synchrotron radiation sources. It has the advantages of low disturbance and high magnetic field uniformity.

[0031] like Figure 1-2 As shown, the present invention designs a nonlinear impact magnet based on nanocrystalline magnetic material, comprising: a magnetic core and an excitation coil assembly;

[0032] The magnetic core specifically includes magnetic poles and a magnetic yoke; the magnetic poles consist of N (N is 4, 6, or 8) magnetic pole units combined into a fully symmetrical ring structure, and the magnetic yoke is a fully symmetrical ring structure located on the periphery of the magnetic poles. The magnetic poles are made by stacking nanocrystalline strips, and the nanocrystalline magnetic core can effectively suppress eddy currents.

[0033] The excitation coil assembly is located outside each magnetic pole unit.

[0034] The magnetic core is used to generate a high-gradient N-pole magnetic field and to provide mechanical support and fixation for the excitation coil, ensuring the stability and reliability of the entire magnet structure. The excitation coil assembly is supplied with excitation current, which generates a magnetic field according to the principle of electromagnetic induction and couples with the magnetic core to improve the utilization and effectiveness of the magnetic field.

[0035] In this invention, the design of the magnetic core structure is as follows:

[0036] The magnetic poles in the magnetic core are made by stacking nanocrystalline ribbons. The nanocrystalline ribbons are selected from one of iron-based nanocrystalline alloys, nickel-based nanocrystalline alloys, cobalt-based nanocrystalline alloys, aluminum-based nanocrystalline alloys, and magnesium-based nanocrystalline alloys. Among them, iron-based nanocrystalline alloys include Finemet type and Nanoperm type.

[0037] Finemet type includes Fe a Co b Si x B y Nb n Cu m Where 70≤a≤85, 0≤b≤15, 10≤x≤16, 5≤y≤12, 1≤n≤5, 0.5≤m≤3 (at%), Fe is preferred. 73.5 Si 13.5 B9Nb3Cu1; Nanoperm type: includes Fe e Zr d B e Cu f Where 80≤c≤90, 3≤d≤10, 5≤e≤12, 0.5≤f≤3 (at%), Fe is preferred. 84 Zr7B8Cu1.

[0038] Nickel-based nanocrystalline alloys include Ni p Fe x Mo γ Where 75≤p≤85, 15≤x≤25, 0≤y≤5 (at%), Ni is preferred. 81 Fe 17 Mo2; cobalt-based nanocrystalline alloys including the Vitroperm series; aluminum-based nanocrystalline alloys including Al n Ni x Y γ Where 80≤n≤90, 5≤x≤15, 2≤y≤10 (at%), Al is preferred. 85 Ni 10 Y5; Magnesium-based nanocrystalline alloys include Mg p Zn x Ca γ Where 95≤p≤99, 0.5≤x≤3, 0.5≤y≤5 (at%), Mg is preferred. 97 Zn1Ca2.

[0039] The preparation of iron-based nanocrystalline ribbons, as shown in the example below, involves a phase transformation process from amorphization to nanocrystallization. This process mainly includes vacuum melting, vacuum remelting, composition analysis and compensation, casting, and annealing. Vacuum melting primarily prepares a homogeneous master alloy ingot, removes gaseous impurities (O, H, N, etc.), and controls the content of harmful elements (C, S, P). Vacuum remelting further purifies the melt, eliminates compositional segregation, and ensures microscopic uniformity. Composition analysis ensures that the atomic percentages of elements such as Fe, Si, B, Nb, and Cu conform to the designed formula. When the analysis results deviate from the designed values, compensation operations are required to maintain compositional uniformity. The casting process transforms the melt into an amorphous ribbon precursor. Finally, the cast ingot is heated to a specific temperature, held at that temperature, and then slowly cooled.

[0040] Under the condition that the excitation power supply is a half-sinusoidal pulse width in the microsecond range, the core material of the nonlinear impact magnet needs to meet the requirements of high permeability, low loss and good high-frequency characteristics. The saturation magnetic induction intensity of the high permeability nanocrystalline core is significantly higher than that of the traditional ferrite material (1.2-1.38T), while maintaining good high-frequency characteristics. Therefore, considering the above material properties, the high permeability nanocrystalline core is selected for the core structure.

[0041] Furthermore, the part of each magnetic pole unit near the center of the ring is the magnetic pole head, and the end of the magnetic pole head has a gradually changing arc structure; the part of each magnetic pole from the yoke to the magnetic pole head is the main body of the magnetic pole, which is a stepped structure with the outline gradually shrinking.

[0042] Depend on Figure 1 As shown, the main body of each magnetic pole unit is composed of 6-8 layers of nanocrystalline ribbon stacked together in a stepped manner, starting from the bottom and gradually shrinking along the design contour. After reaching a total thickness of 20mm, it is encapsulated and cured with epoxy resin. The end of the magnetic pole head adopts "arc gradient stacking", in which the nanocrystalline ribbon is cut into an arc shape, and the stacking thickness gradually decreases from the main body of the magnetic pole to the end, ensuring a uniform magnetic field gradient on the surface of the pole head.

[0043] Specifically, the nanocrystalline ribbons are cut into trapezoidal or rectangular units with dimensional accuracy controlled within ±5μm. The edges are laser-cut to reduce burrs and are insulated. A 0.5μm thick polyimide film is laid between each layer of ribbons. During lamination, the insulating film is bonded to the ribbons through vacuum hot pressing to reduce eddy current loss.

[0044] In this invention, the magnetic poles are preferably composed of eight magnetic pole units arranged in a fully symmetrical ring structure. This fully symmetrical ring structure allows the magnetic field to exhibit a highly symmetrical distribution in both the radial and circumferential directions, improving magnetic field uniformity and enhancing mechanical stability, thus improving structural stability. Furthermore, the fully symmetrical ring structure formed by the eight magnetic pole units can effectively suppress the generation of stray magnetic fields.

[0045] In this invention, the magnetic yoke is made of pure iron or low-carbon steel (DT4), with a saturation magnetic induction intensity as high as 2T. The manufacturing process is mature, including smelting, casting, machining, and heat treatment. Furthermore, the magnetic yoke and magnetic poles are connected mechanically and with epoxy resin adhesive.

[0046] The design of the magnetic core structure of the excitation coil unit in this invention is as follows:

[0047] The excitation coil assembly is made of copper wire and is wound around the outside of each magnetic pole body.

[0048] Furthermore, the excitation coil assembly uses oxygen-free copper enameled wire windings with high conductivity, and employs layered winding to ensure the symmetry of the magnetic field distribution.

[0049] Alternatively, insulating support units may be provided between the layers of the excitation coil assembly and at the edges of the side coils for insulating isolation between the coil layers. These insulating support units may include, but are not limited to, one of polyimide film, polytetrafluoroethylene (PTFE) film, or glass fiber impregnated film.

[0050] Furthermore, the excitation coil assembly also includes a cooling system unit, embedded along the magnetic pole contour, which uses circulating coolant to remove heat generated by resistance loss, preventing the coil temperature from becoming too high and increasing resistance. For example, the cooling system includes interlayer cooling pipes, a cooling jacket, lead terminals, and a cooling circuit assembly. The interlayer cooling pipes are located between each layer of the coil, and flat stainless steel cooling pipes are embedded along the arc-shaped contour of the magnetic pole. Both ends of the cooling pipes extend to the outside of the coil, serving as inlet / outlet water interfaces. The cooling jacket covers the outer layer of the cooling pipes. The lead terminals are connected to an external water tank, and water pipes are connected from the outside of the coil. The water tank pump is placed next to the coil.

[0051] For example, design a suitable coil cross-sectional size according to the preset magnetic pole structure size parameters, and reserve space for insulation layer thickness. Select 1mm×0.5mm flat copper wire, cut the polyimide film insulation layer into a trapezoidal shape, so that its size is slightly larger than the iron core slot, and cover the edge of the wound coil to avoid short circuit.

[0052] To improve the space utilization of the magnet, a trapezoidal coil winding is used, and the wire pretreatment annealing process reduces stress. For example, the winding proceeds back and forth from the bottom of the magnetic pole to the top, ensuring a uniform 0.5mm spacing between each turn. Each layer of turns is insulated with a polyimide film. A total of six layers are wound, using a CNC winding machine programmed to reduce turns in a "5-4-3-2-1" gradient. After winding, a 0.2mm glass fiber tape is wrapped around the outside of the coil to prevent short circuits and partial discharges between adjacent coils.

[0053] It should be noted that by optimizing the magnetic pole parameter structure and the angle parameters of the magnetic pole head, the integrated field strength that meets the design requirements can be obtained, while ensuring that the magnetic field amplitude in the field-free region is less than 1%. Specifically, in magnet design, the magnetic pole head angle is a key parameter determining the spatial distribution of the magnetic field and the magnetic induction intensity. Based on the fundamental characteristic that magnetic field lines are "perpendicular to the magnetic pole surface," the initial propagation direction of the magnetic field lines will change when the magnetic pole head angle α changes. From the perspective of electromagnetic field theory, a small adjustment of the magnetic pole head angle will change the higher-order components of the magnetic field (such as hexapole and octapole components). By optimizing the angle parameters, the interference of higher-order components can be counteracted, ensuring the uniformity of the main magnetic field and weakening the stray magnetic field in the field-free region. Similarly, parameters such as the magnetic pole width will also affect the magnitude and uniformity of the generated magnetic induction intensity.

[0054] This invention designs a nonlinear impact magnet based on nanocrystalline magnetic material and its matching power supply system, which includes the nonlinear impact magnet based on nanocrystalline magnetic material and the excitation power supply as described above. The excitation coil lead of the magnet is connected to the output terminal of the excitation power supply through a terminal block.

[0055] The excitation power supply provides a bit-second-level fast pulse current to power the entire excitation system. The pulse current output by the excitation power supply generates a magnetic field through the excitation coil. The fully symmetrical structure of the magnetic core guides the magnetic field to form an octagonal distribution. The three elements work together in a closed loop of "power input - coil magnetic energy conversion - core magnetic field constraint" to achieve the low-disturbance, highly uniform magnetic field required for off-axis injection.

[0056] In this invention, the design of the excitation power supply is as follows:

[0057] The terminals are, for example, specially made high-voltage terminals M8 threaded ceramic insulated terminals. The terminals are gold-plated to reduce contact resistance, and the housing is made of polytetrafluoroethylene insulating material. The withstand voltage meets the insulation requirements during pulse operation. All power return lines converge to a single-point grounding copper plate.

[0058] The excitation power supply includes a main power module, which uses power devices such as IGBTs to form an inverter circuit. It generates the required half-sine pulse current according to the control signal and uses an energy storage capacitor to provide a stable DC voltage input to the power module; a control and drive module for generating high-precision timing control circuits and amplifying the control signals to drive the power devices; a protection and detection module for quickly cutting off the power module output when the current exceeds the rated value (such as excitation coil overload) or the voltage is abnormal; and a parameter adjustment module for finely adjusting the magnetic field strength to meet the off-axis injection requirements under different beam energies (1-3.5GeV).

[0059] Furthermore, the excitation power supply adopts a 2 / N power supply synchronous parallel power supply system. Each power supply group of the excitation power supply drives two spatially symmetrical coils, and the current directions of adjacent magnetic poles are opposite.

[0060] For example, the magnetic poles preferably consist of a fully symmetrical ring structure composed of eight identical magnetic pole units. Based on the expected model design and power supply parameter specifications, a scheme of four power supplies connected in parallel and independently powers the magnets. Figure 3 This is a schematic diagram of the current flow in an eight-pole magnet coil. L1-L8 represent the equivalent inductance of the eight magnetic pole coils, with the numbers corresponding to the pole positions, arranged in circumferential order (1-8). Power supplies U1-U4 represent the positive outputs of four independent pulse power supplies. GND represents the common ground terminal.

[0061] The power supply adopts the principle of symmetrical current distribution: each power supply drives two spatially symmetrical coils to ensure magnetic field symmetry; the current directions of adjacent magnetic poles are opposite, such as counterclockwise for pole 1 and clockwise for pole 2; and the lead lengths from the power supply output terminal to the coil are equal; the synchronous power supply of the four power supplies must ensure high synchronization accuracy and that parameters such as current distortion rate are within a certain error range to ensure that a highly uniform magnetic field strength can be generated to meet the beam injection intensity requirements, while also meeting the requirement that the central magnetic field strength in the field-free region is less than 1%. Therefore, it is necessary to ensure that the synchronization error time of the four power supplies is controlled within ±10ns, the current distortion rate THD is less than 1%, and the proportion of stray magnetic field components outside the main magnetic field is less than 1%, significantly reducing the proportion of multipole field components and improving magnetic field uniformity.

[0062] The magnetic field distribution generated by the magnet of the present invention in the mid-plane is as follows: Figure 4 As shown, the magnetic induction intensity at the injection point is 312.81 Gs, the amplitude in the field-free region is less than 1%, and the stray component accounts for less than 0.1% of the main magnetic field.

[0063] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of protection of this invention and its equivalents, this invention also intends to include these modifications and variations. The above-described embodiments are merely preferred embodiments given to fully illustrate this invention, and their scope of protection is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on this invention are all within the scope of protection of this invention.

Claims

1. A nonlinear impact magnet based on nanocrystalline magnetic materials, characterized in that, include: A magnetic core and excitation coil assembly; the magnetic core includes magnetic poles and a magnetic yoke; Both the magnetic pole and the magnetic yoke are fully symmetrical ring structures, and the magnetic yoke is located on the periphery of the magnetic pole; The magnetic pole comprises N identical magnetic pole units, where N is 4, 6, or 8, and the magnetic pole is made by laminating nanocrystalline strips; the excitation coil assembly is wound around the magnetic pole body of each magnetic pole unit.

2. The nonlinear impact magnet based on nanocrystalline magnetic materials according to claim 1, characterized in that, The nanocrystalline ribbon is selected from one of iron-based nanocrystalline alloys, nickel-based nanocrystalline alloys, cobalt-based nanocrystalline alloys, aluminum-based nanocrystalline alloys, or magnesium-based nanocrystalline alloys; wherein, the iron-based nanocrystalline alloys include Finemet-type iron-based nanocrystalline alloys or Nanoperm-type iron-based nanocrystalline alloys.

3. The nonlinear impact magnet based on nanocrystalline magnetic materials according to claim 2, characterized in that, The Finemet-type iron-based nanocrystalline alloy preferably contains Fe. 73.5 Si 13.5 B9Nb3Cu1, the Nanoperm-type iron-based nanocrystalline alloy preferably contains Fe. 84 Zr7B8Cu1, the nickel-based nanocrystal composite is preferably Ni 81 Fe 17 Mo2, the aluminum-based nanocrystalline alloy preferably Al 85 Ni 10 Y5, the magnesium-based nanocrystalline alloy is preferably Mg 97 Zn1Ca2.

4. The nonlinear impact magnet based on nanocrystalline magnetic materials according to claim 1, characterized in that, Each magnetic pole unit comprises a magnetic pole head and a magnetic pole body, wherein the magnetic pole head is the portion of the magnetic pole unit located near the center of the annular structure, and the magnetic pole body is the portion located between the magnetic pole head and the magnetic yoke; The magnetic pole head has a gradually changing arc structure; The magnetic pole body has a stepped structure with its outline gradually receding from the magnetic yoke to the magnetic pole head.

5. The nonlinear impact magnet based on nanocrystalline magnetic material according to claim 1, characterized in that, The magnetic pole comprises a fully symmetrical ring structure consisting of eight identical magnetic pole units.

6. The nonlinear impact magnet based on nanocrystalline magnetic material according to claim 1, characterized in that, The magnetic yoke is made of pure iron or DT4.

7. The nonlinear impact magnet based on nanocrystalline magnetic materials according to claim 1, characterized in that, The excitation coil assembly is made of copper wire and is wound along the outer contour of the magnetic pole body.

8. The nonlinear impact magnet based on nanocrystalline magnetic material according to claim 1, characterized in that, The excitation coil assembly is an oxygen-free copper enameled wire winding wound along the outer contour of the magnetic pole body; or, the excitation coil assembly has insulating support units between layers and at the edges of the side coils.

9. The nonlinear impact magnet based on nanocrystalline magnetic materials according to claim 1, characterized in that, The excitation coil assembly also includes a cooling system unit, which is embedded along the contour of the magnetic pole body.

10. A nonlinear impact magnet and its matching power supply system, characterized in that, The device includes a nonlinear impact magnet based on nanocrystalline magnetic material and an excitation power supply as described in any one of claims 1-9 above. The excitation coil lead of the nonlinear impact magnet based on nanocrystalline magnetic material is connected to the output terminal of the excitation power supply through a terminal block, and the excitation power supply is supplied synchronously in parallel by 2 / N power supplies.

Images