Method, device, medium and equipment for optimizing the uniformity of the integral field of a two-pole magnet

Abstract

The present invention relates to a method, device, medium and equipment for optimizing the uniformity of the integral field of a dipole magnet, including: establishing a dipole magnet model, beveling its end, and obtaining an end beveling block or a shim block model; calculating the contribution of the end beveling block or the shim block model to the integral field; calculating the contribution of the end beveling block or the shim block model to the integral field of all points in the good field area; establishing and solving a linear programming equation group to obtain the beveling thickness of the end beveling block or the shim block model at different positions; bringing the beveling depth of the end beveling block or the shim block model at different positions into finite element software for simulation verification, and obtaining the optimized integral field uniformity, which is better than the physical requirement result, that is, completing the optimization design. The method of the present invention can perform rapid magnetic field shimming by solving a linear equation group combined with an end shim in the secondary magnetic repair process after magnetic field measurement, greatly improving the work efficiency of calculation and testing.

Description

Technical Field

[0001] The invention relates to a method, a device, a medium and equipment for optimizing the uniformity of the integral field of a dipole magnet, and belongs to the technical field of optimizing the uniformity of the integral field of a dipole magnet. Background Art

[0002] The accelerator dipole magnet is the main component of the accelerator. Its main function is to provide a uniform vertical magnetic field within the uniform area required by physics, so that the motion trajectory of the beam can be deflected as required. The uniformity of the magnet's integrated field determines the quality of the beam.

[0003] The key components of the accelerator dipole magnet are the coils that generate the excitation and the iron core that binds the magnetic field shape. The optimization of the integral magnetic field uniformity is mainly achieved by beveling the end of the iron core pole head. At present, the end beveling size of the dipole magnet integral field uniformity optimization on the accelerator devices (HIRFL-CSR, HIMM, CSNS, etc.) currently in operation in China is mainly achieved through finite element software simulation calculation plus human judgment. Moreover, the magnetic field correction of the dipole magnet after magnetic field measurement still needs to be manually optimized using finite element software. Manual optimization assisted by finite element software has a large amount of calculation, is time-consuming, complex, and has a long waiting time for the magnetic correction process, resulting in low efficiency in design, secondary magnetic correction and testing.

[0004] The existing high-intensity heavy-ion accelerator facility HIAF (High Intensity Heavy-ion Accelerator Facility) involves dipole magnets of various specifications, and has high physical requirements. These dipole magnets have the characteristics of large good field range, wide magnetic field range, high field uniformity, high harmonic requirements, and fast magnetic field change rate of some magnets. The optimization process must not only ensure that the field uniformity meets the requirements, but also take into account the range of magnetic field changes, which greatly increases the difficulty and workload of the optimization design. Summary of the invention

[0005] In view of the above technical problems, the present invention provides a method, device, medium and equipment for optimizing the integral field uniformity of a dipole magnet. The method of the present invention can perform rapid magnetic field shimming by solving a set of linear equations combined with end gaskets during the secondary magnetic repair process after magnet optimization design and magnetic field measurement, thereby greatly improving the work efficiency of calculation and testing.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for optimizing the integral field uniformity of an accelerator dipole magnet, comprising:

[0008] A dipole magnet model is established, and its end is beveled to obtain an end beveled block or a shim block model;

[0009] Calculate the contribution of the end bevel block or shim block model to the integral field;

[0010] Calculate the contribution of the end bevel block or padding block model to the integral field of all points in the good field area;

[0011] Establish and solve a linear programming equation group to obtain the bevel thickness of the end bevel block or shim block model at different positions;

[0012] The bevel depths of the end bevel blocks or padding block models at different positions are brought into the finite element software for simulation and verification to obtain the optimized integral field uniformity, which is better than the physical requirement result, thus completing the optimization design.

[0013] In the method for optimizing the integral field uniformity of the accelerator dipole magnet, preferably, the end of the dipole magnet is beveled by sequentially arranging bevel blocks or shim block models of fixed width and different depths or thicknesses, the width of the bevel blocks or shim block models can be selected arbitrarily, and the number of bevel blocks or shim block models depends on the good field area width and the width of the bevel blocks or shim block models. The method for optimizing the integral field uniformity of the present invention: The optimization of the integral field uniformity (△BL / BL) of the accelerator core-dominated dipole magnet is mainly achieved by changing the magnetic length on different paths and thus changing the BL change on different paths by beveling the end.

[0014] In the method for optimizing the uniformity of the integral field of the accelerator dipole magnet, preferably, the calculation process of the contribution of the end bevel block or shim block model to the integral field is as follows: without considering the magnetic field coupling effect, the integral field change △BL of point P in the good field region is obtained by linearly superposing the magnetic field contributions of the end bevel block or shim block model at different positions, that is:

[0015] △B P =∑m jP X j (1)

[0016] Among them, △B P X is the superposition of the magnetic field contributions of all end bevel blocks or shim blocks to point P in the good field area. j is the thickness of the jth bevel block or shim block model, m jP It is the contribution of the unit thickness of the j-th beveling block or shim block model to the magnetic field at point P, that is, the contribution coefficient.

[0017] In the method for optimizing the uniformity of the integral field of the accelerator dipole magnet, preferably, the contribution of the end bevel block or shim block model to the integral field at any point in the good field region is calculated as follows: Based on formula (1), the integral magnetic field change at any point i is obtained as follows:

[0018] △B i =∑m ij X j(2)

[0019] Among them, △B i The magnetic field contribution superposition of all end bevel blocks or shim block models to any point i in the good field area; m ij is the contribution coefficient of the jth beveling block or shimming block model to any i point;

[0020] Using matrix form, formula (2) can be rewritten as:

[0021]

[0022] In short:

[0023] △B=MX (3)

[0024] Where △B is the column vector of the integrated magnetic field change, △B=(△B1,△B2,…△B n ) T The magnetic field column vector is obtained by comparing the integrated magnetic field before optimization with the ideal integrated magnetic field BL; X is the thickness of each bevel block or shim block model, X = (X1, X2, ... X n ) T , is the required solution; M is the contribution matrix, which represents the contribution of the bevel block or shim block model of unit thickness at different positions to the integral field at different positions.

[0025] In the method for optimizing the integral field uniformity of the accelerator dipole magnet, preferably, the contribution matrix of a single beveling block or shimming block model is obtained by the following formula:

[0026] Firstly, finite element software such as Opera / Anays is used to simulate and calculate a single bevel block or shim block model, and the contribution of the unit thickness bevel block or shim block model to the magnetic field at different distances from the bevel block or shim block model is obtained, and the contribution matrix of the single bevel block or shim block model is obtained. According to its symmetry, the contribution matrix is ​​expressed as follows:

[0027] L0=(m n / 2 ,…,m2,m1,m0,m1,m2,…, m n / 2 ) T (4)

[0028] where m0,m1,m2,…,m n / 2 are the contribution matrix coefficients at different distances from the bevel block or padding block model, △x is the distance between two adjacent field value points, m n / 2 is the contribution coefficient of the distance bevel block △x×n / 2; m2 is the contribution matrix coefficient of the distance bevel block △x×2; m1 is the contribution matrix coefficient of the distance bevel block △x; m0 is the contribution matrix coefficient of the distance bevel block △x×0.

[0029] Then, according to the position continuity of the bevel block or padding block model and the cyclic repeatability of the matrix coefficient, the generation of the coefficient matrix is ​​simplified to obtain the contribution matrix Li of the bevel block or padding block model at different positions; the width of the bevel block or padding block model is w, and the matrix of each bevel block or padding block model is expressed as follows:

[0030] L -m =(m n / 2-mw / n ,…,m2,m1,m0,m1,m2,…,m n / 2 ,0,…,0) T

[0031] …

[0032] L -1 =(m n / 2-w / n ,…,m2,m1,m0,m1,m2,…,m n / 2 ,0,…,0) T

[0033] L0=(m n / 2 ,…,m2,m1,m0,m1,m2,…,m n / 2 ) T

[0034] L1=(0,…,0,m n / 2 ,…,m2,m1,m0,m1,m2,…,m n / 2-w / n ) T

[0035] …

[0036] L m =(0,…,0,m n / 2 ,…,m2,m1,m0,m1,m2,…,m n / 2-mw / n ) T

[0037] Then combine all sub-matrices to get the complete contribution matrix:

[0038] M=(L -m ,…,L -1 ,L0,L1,…,L m ) (5)

[0039] Among them, L -m ,…,L -1 ,L0,L1,…,L m are the contribution matrices corresponding to the -m, ..., -1, 0, 1, ..., mth slashing blocks. m0, m1, m2, ..., m n / 2-w / n ,,…,m n / 2-mw / n ,…,m n / 2They are the contribution matrix coefficients at different distances from the beveling block or shimming block model. n / 2-mw / n m is the distance to the bevel block △x×(n / 2-mw / n) position contribution coefficient; n / 2-w / n It is the position contribution coefficient of the distance beveling block △x×(n / 2-w / n).

[0040] The method for optimizing the integral field uniformity of the accelerator dipole magnet is preferably a linear programming equation system as follows: The goal of passive shimming is to compensate for the non-uniform magnetic field components of the magnet with the least model depth (or thickness) of the bevel block or shim block. In this way, the passive shimming problem can be converted into a linear programming problem, which is mathematically described as follows:

[0041] Minimize∑Xi (6)

[0042] The matrix form is:

[0043] MX≤△Bt+∈BL0 (7)

[0044] -MX≤-△Bt+∈BL0 (8)

[0045] Xi≥0 (9)

[0046] Xi≤Xmax(i) (10)

[0047] Among them, Xi is the beveling depth; △Bt is the column vector of the integrated magnetic field change; BL0 is the integrated magnetic field at the center of the magnet; ∈BL0 is the deviation between the magnetic field generated by the beveling block or shim block model array and the magnetic field inhomogeneity component that needs to be corrected; ∈ is the deviation between the magnetic field generated by the beveling block or shim block model array and the magnetic field inhomogeneity component that needs to be corrected; Xmax(i) is the maximum thickness limit of the i-th beveling block or shim block model.

[0048] The objective function formula (6) is a simple summation of all the cutting depths (or padding thicknesses), and we need to minimize the cutting (or padding) amount.

[0049] The constraint condition formula (9) ensures the non-negativity of the truncated (or padded) shape, while formula (10) constrains the maximum size of the truncated (or padded) shape and reduces the discreteness of the truncated (or padded) shape.

[0050] By solving the linear programming problem defined by formulas (6) to (10), the result vector Xres can be obtained, which gives the thickness value of the beveling (or padding) at each position. Since the minimum thickness size of the processing or padding piece is subject to production constraints, the optimized thickness value must be approximated so that the operability of the beveling (or padding) can be achieved.

[0051] Thus, due to the combined influence of factors such as the average approximation of the coefficient matrix and the coupling effect of the beveled (or padded) blocks, the magnetic field distribution obtained after the initial uniformity often fails to meet the uniformity requirements, which requires 2 to 3 iterative calculations to correct these errors.

[0052] After the finite element simulation calculation of the magnetic field after the first shimming, the new magnetic field inhomogeneity △Bt that needs to be corrected can be obtained. The adjustment plan of the bevel (or shimming) thickness required in the next step is based on the previous shimming piece arrangement, that is, the thickness is increased or decreased based on the original bevel (or shimming). In this way, the linear programming model of the first step of the shimming problem needs to make corresponding adjustments to the thickness constraint conditions. The new linear programming mathematical model is:

[0053] Minimize∑Xi (11)

[0054] MX≤△Bt+∈BL0 (12)

[0055] -MX≤-△Bt+∈BL0 (13)

[0056] Xi≥-Xpre(i) (14)

[0057] Xi≤Xmax-Xpre(i) (15)

[0058] Where Xi is the bevel depth; Xpre(i) is the thickness of the i-th shim obtained by solving the linear programming in the previous step. The constraint formulas (14) and (15) ensure that the increase or decrease of the new bevel (or shimming) thickness will not reduce the thickness to a negative value, or increase it too much to exceed the total thickness limit.

[0059] Solve the new linear programming problem defined by formula (11) to formula (15) to obtain a new result vector Xres, which gives the adjustment scheme of the bevel (or padding) at each position. A positive value represents an increase in thickness, and a negative value represents a decrease in thickness. According to the new shimming scheme, the thickness of the bevel (or padding) array is increased or decreased accordingly. If the uniformity meets the requirements, the shimming is completed, otherwise the previous step is repeated. The entire shimming iterative process is shown in Figure 1 .

[0060] The beveling size is completed by beveling in the machining center. The shim block is usually made of cold-rolled soft magnetic metal, which is ground and cut to obtain a minimum thickness of 0.1mm. Therefore, when shimming, the arrangement of the shimming blocks at each position can only be an integer multiple of 0.1mm thickness, so there is a deviation from the theoretical calculation results. Therefore, using the thickness-based shimming method, after the magnetic field uniformity is improved to a certain extent, it is difficult to further improve the magnetic field uniformity.

[0061] Based on the above reasons, when the shimming reaches a certain degree, the present application proposes to finely shim the magnetic field by subdividing the width of the bevel (or shimming) block, using shims of different areas. The above linear programming algorithm is also used for iterative correction and iterative shimming, so as to achieve a high degree of uniformity.

[0062] A second aspect of the present invention provides an accelerator dipole magnet integral field uniformity optimization device, comprising:

[0063] The first processing unit is used to establish a dipole magnet model and bevel its end to obtain an end bevel block or a shim block model;

[0064] The second processing unit is used to calculate the contribution of the end bevel block or the shim block model to the integral field;

[0065] The third processing unit is used to calculate the contribution of the end beveling block or shimming block model to the integral field of all points in the good field area;

[0066] The fourth processing unit is used to establish and solve a linear programming equation group to obtain the bevel thickness of the end bevel block or shim block model at different positions;

[0067] The fifth processing unit is used to bring the beveling depth of the end beveling block or padding block model at different positions into the finite element software for simulation verification to obtain the optimized integral field uniformity, which is better than the physical requirement result, thus completing the optimization design.

[0068] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the steps of the above-mentioned method for optimizing the integral field uniformity of an accelerator dipole magnet are implemented.

[0069] A fourth aspect of the present invention provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned method for optimizing the integral field uniformity of the accelerator dipole magnet when executing the computer program.

[0070] The present invention adopts the above technical solution, which has the following advantages:

[0071] 1. The present invention calculates the end bevel size by solving a group of linear equations, and then verifies and confirms it through finite element software, which can effectively reduce the blindness of the calculation, improve the efficiency of the magnetic field optimization, and improve the accuracy of the optimization.

[0072] 2. The present invention can perform rapid magnetic field shimming in the secondary magnetic repair process after magnetic field measurement by solving a linear equation group combined with end gaskets, which greatly improves the working efficiency of calculation and testing.

[0073] 3. The present invention approaches the limit value infinitely through multiple solutions, and the optimization result is better than the traditional empirical calculation result.

[0074] 4. The present invention can be widely used in optimizing the integral field uniformity of a core-dominated accelerator dipole magnet. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1 A flow chart of optimizing the integral field uniformity using a linear programming algorithm provided by an embodiment of the present invention;

[0076] Figure 2 A structural diagram of a BRing two-pole magnet for the HIAF project provided in this embodiment of the present invention;

[0077] Figure 3 A cross-sectional view of a BRing two-pole magnet of the HIAF project provided for this embodiment of the present invention; DETAILED DESCRIPTION

[0078] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work are within the scope of protection of the present invention.

[0079] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second", "third", "fourth", "upper", "lower", "left and right" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0080] like Figure 1 As shown in the figure, it is a flowchart of optimizing the integral field uniformity using a linear programming algorithm. Take the optimization of the integral field uniformity of the BRing dipole magnet in the HIAF project as an example (e.g. Figure 2 , 3 Before the start of field shimming, finite element software such as Opera / Anays is used to perform field simulation calculations, and the integral field uniformity before beveling and under a single beveling block is calculated respectively. The contribution of a single beveling block to the magnetic field at different distances from the beveling block is compared, and the contribution matrix of a single beveling block is obtained.

[0081] L0=(m n / 2 ,…,m2,m1,m0,m1,m2,…,m n / 2 ) T

[0082] Then, the generation of the coefficient matrix is ​​simplified according to the position continuity of the bevel block and the cyclic repeatability of the matrix coefficients. The width of the good field area of ​​the dipole magnet is 180mm, the interval △x of the integral magnetic field points is 5mm, and the number of magnetic field vectors n = 180 / 5+1 = 37. Usually, the total width of the bevel will be greater than the good field area width required by physics. In this example, the width of the bevel block is selected as 35mm, the number is selected as 7 blocks, and the number of bevel block sub-matrices is the same as the number of bevel blocks, which is 7. The number of points between two adjacent bevel block sub-matrices is the ratio of the width of the bevel block to the interval of the integral magnetic field points in the good field area = 35 / 5 = 7 points; therefore, the contribution matrix Li of the 7 bevel blocks in different positions is obtained as follows:

[0083] L -3 =(m n / 2-21 ,…,m2,m1,m0,m1,m2,…,m n / 2 ,0,…,0) T

[0084] L -3 =(m n / 2-14 ,…,m2,m1,m0,m1,m2,…,m n / 2 ,0,…,0) T

[0085] L -1 =(m n / 2-7 ,…,m2,m1,m0,m1,m2,…,m n / 2 ,0,…,0) T

[0086] L0=(m n / 2 ,…,m2,m1,m0,m1,m2,…,m n / 2 ) T

[0087] L1=(0,…,0,m n / 2 ,…,m2,m1,m0,m1,m2,…,m n / 2-7 ) T

[0088] L2=(0,…,0,m n / 2 ,…,m2,m1,m0,m1,m2,…,m n / 2-14 ) T

[0089] L3=(0,…,0,m n / 2,…,m2,m1,m0,m1,m2,…,m n / 2-21 ) T

[0090] Combining all sub-matrices gives the complete contribution matrix:

[0091] M=(L -3 ,L -2 ,L -1 ,L0,L1,L2,L3) (4)

[0092] Calculate the product of the integral field uniformity of each point in the good field area before the first optimization and the integral field of the central arc to obtain the column vector of the integral magnetic field change of the first optimization:

[0093] △B=(△B -17 ,△B -16 ,…,△B0,…△B 16 ,△B 17 )

[0094] Solve the product of the physical requirement value of magnetic field uniformity and the size of the integral field BL, obtain the required value of the contribution of the slope to the integral field ∈BL0=BL0×(△BL / BL0), and determine the constraint conditions.

[0095] Because the bevel depth is a positive value, the bevel depth range is set to 0<Xi<Xmax. Use numerical calculation software such as Mathematica / MATLAB to solve the linear programming equation group to obtain the bevel depth of the bevel block at different positions; bring the bevel depth of the bevel block at different positions into the finite element software Opera / Anays for simulation verification to obtain the optimized integral field uniformity; multiply the integral field uniformity of each point in the good field area calculated by the finite element software Opera / Anays with the integral field of the central arc to obtain a new integral magnetic field change column vector:

[0096] △B=(△B -17 ,△B -16 ,…,△B0,…△B 16 ,△B 17 ).

[0097] According to the depth of the bevel block at different positions, the bevel depth limit range -Xpre<Xi<Xmax is re-determined. The second round of linear programming equations is solved using numerical calculation software such as Mathematica / MATLAB, and the newly obtained bevel depths of different bevel blocks are brought into finite element software such as Opera / Anays for simulation verification again.

[0098] Repeat the above operation 2 to 3 times to obtain the final integral field uniformity calculation result, which is better than the physical requirement result, and complete the optimization design.

[0099] Figure 3 Shown is the end bevel matrix after optimization of the BRing fast pulse dipole magnet in the HIAF project.

[0100] A second aspect of the present invention provides an accelerator dipole magnet integral field uniformity optimization device, comprising:

[0101] The first processing unit is used to establish a dipole magnet model and bevel its end to obtain an end bevel block or a shim block model;

[0102] The second processing unit is used to calculate the contribution of the end bevel block or the shim block model to the integral field;

[0103] The third processing unit is used to calculate the contribution of the end beveling block or shimming block model to the integral field of all points in the good field area;

[0104] The fourth processing unit is used to establish and solve a linear programming equation group to obtain the bevel thickness of the end bevel block or shim block model at different positions;

[0105] The fifth processing unit is used to bring the beveling depth of the beveling block or padding block model at different end positions into the finite element software for simulation verification to obtain the optimized integral field uniformity, which is better than the physical requirement result, thus completing the optimization design.

[0106] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-mentioned method for optimizing the integral field uniformity of an accelerator dipole magnet.

[0107] A fourth aspect of the present invention provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned method for optimizing the integral field uniformity of the accelerator dipole magnet when executing the computer program.

[0108] The present invention is described in terms of flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to specific embodiments. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0109] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0110] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for optimizing the integral field uniformity of an accelerator dipole magnet, characterized in that: include: A dipole magnet model is established, and its end is beveled to obtain an end beveled block or a shim block model; Calculate the contribution of the end bevel block or shim block model to the integral field; Calculate the contribution of the end bevel block or padding block model to the integral field of all points in the good field area; Establish and solve a linear programming equation group to obtain the bevel thickness of the end bevel block or shim block model at different positions; The bevel depths of the end bevel blocks or shim blocks at different positions are brought into the finite element software for simulation and verification, and the optimized integral field uniformity is obtained, which is better than the physical requirement result, and the optimization design is completed; The calculation process of the contribution of the end bevel block or shim block model to the integral field is as follows: Ignoring the magnetic field coupling effect, the integral field change △BL at point P in the good field area is obtained by linearly superposing the magnetic field contributions of the end bevel block or shim block model at different positions, that is: △B P =∑m jP X j (1) Among them, △B P is the superposition of the magnetic field contributions of all end bevel blocks or shim blocks to point P, X j is the thickness of the jth bevel block or shim block model, m jP is the contribution of the jth bevel block or shim block model per unit thickness to the magnetic field at point P, i.e., the contribution coefficient; The contribution of the end bevel block or shim block model to the integral field at any point in the good field area is calculated as follows: Based on formula (1), the integral magnetic field change at any point i is obtained as follows: △B i =∑m ij X j (2) Among them, △B i The magnetic field contribution superposition of all end bevel blocks or shim block models to any point i in the good field area; m ij is the contribution coefficient of the j-th beveling block or shimming block model to the i-th point; Formula (2) can be abbreviated in matrix form as: △B=MX(3) Where X is the thickness of each beveling block or shim block model, X=(X1, X2, …X n ) T , is the required solution; M is the contribution matrix, which represents the contribution of the bevel block or shim block model of unit thickness at different positions to the integral field at different positions; The linear programming equations are as follows: Minimize∑Xi(6) Among them, Xi is the cutting depth.

2. The method for optimizing the integral field uniformity of an accelerator dipole magnet according to claim 1, characterized in that: The method for beveling the ends of the dipole magnet is: using a fixed width, different depths or thicknesses of beveling blocks or shim block models arranged in sequence, the width of the beveling blocks or shim block models can be selected arbitrarily, and the number of beveling blocks or shim block models depends on the good field area width and the width of the beveling blocks or shim block models.

3. The method for optimizing the integral field uniformity of an accelerator dipole magnet according to claim 1, characterized in that: The contribution matrix of a single beveling block or shim block model is obtained by the following formula: L0=(m n / 2 ,…,m2,m1,m0,m1,m2,…, m n / 2 ) T (4) The complete contribution matrix M formula is as follows: M=(L -m ,…, L -1 , L0, L1,…, L m ) (5) Among them, L -m ,…, L -1 , L0, L1,…, L m are the contribution matrices corresponding to the -m, ..., -1, 0, 1, ..., mth slashing blocks; m0, m1, m2, ..., m n / 2 are the contribution matrix coefficients at different distances from the bevel block or padding block model, △x is the distance between two adjacent field value points, m n / 2 is the contribution coefficient of the distance bevel block △x×n / 2; m2 is the contribution matrix coefficient of the distance bevel block △x×2; m1 is the contribution matrix coefficient of the distance bevel block △x; m0 is the contribution matrix coefficient of the distance bevel block 0.

4. An accelerator dipole magnet integral field uniformity optimization device, characterized in that: include: The first processing unit is used to establish a dipole magnet model and bevel its end to obtain an end bevel block or a shim block model; The second processing unit is used to calculate the contribution of the end bevel block or the shim block model to the integral field; The calculation process of the contribution of the end bevel block or shim block model to the integral field is as follows: Ignoring the magnetic field coupling effect, the integral field change △BL at point P in the good field area is obtained by linearly superposing the magnetic field contributions of the end bevel block or shim block model at different positions, that is: △B P =∑m jP X j (1) Among them, △B P is the superposition of the magnetic field contributions of all end bevel blocks or shim blocks to point P, X j is the thickness of the jth bevel block or shim block model, m jP is the contribution of the jth bevel block or shim block model per unit thickness to the magnetic field at point P, i.e., the contribution coefficient; The third processing unit is used to calculate the contribution of the end beveling block or shimming block model to the integral field of all points in the good field area; The contribution of the end bevel block or shim block model to the integral field at any point in the good field area is calculated as follows: Based on formula (1), the integral magnetic field change at any point i is obtained as follows: △B i =∑m ij X j (2) Among them, △B i The magnetic field contribution superposition of all end bevel blocks or shim block models to any point i in the good field area; m ij is the contribution coefficient of the j-th beveling block or shimming block model to the i-th point; Formula (2) can be abbreviated in matrix form as: △B=MX(3) Where X is the thickness of each beveling block or shim block model, X=(X1, X2, …X n ) T , is the required solution; M is the contribution matrix, which represents the contribution of the bevel block or shim block model of unit thickness at different positions to the integral field at different positions; The fourth processing unit is used to establish and solve a linear programming equation group to obtain the bevel thickness of the end bevel block or shim block model at different positions; The linear programming equations are as follows: Minimize∑Xi(6) Where, Xi is the cutting depth; The fifth processing unit is used to bring the beveling depth of the beveling block or padding block model at different end positions into the finite element software for simulation verification to obtain the optimized integral field uniformity, which is better than the physical requirement result, thus completing the optimization design.

5. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for optimizing the integral field uniformity of an accelerator dipole magnet according to any one of claims 1 to 3 are implemented.

6. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method for optimizing the integral field uniformity of the accelerator dipole magnet according to any one of claims 1 to 3 are implemented.

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