Magnetic saturation compensation magnet yoke optimization method, device, equipment, medium and program

Abstract

The invention relates to the technical field of electromagnetic equipment, in particular to a magnet yoke optimization method and device for magnetic saturation compensation, equipment, a medium and a program, and the method comprises the steps: recognizing a potential magnetic saturation region, so as to configure at least one compensation magnet in the potential magnetic saturation region; calculating the internal magnetic induction intensity of a magnet yoke near the compensation magnet, judging whether the plurality of characteristic parameters and the compensation effect of the compensation magnet meet preset related conditions or not, and if yes, obtaining key parameters related to the compensation effect; and determining a preliminary magnetic saturation compensation scheme, and performing iterative optimization on the preliminary magnetic saturation compensation scheme until a preset iteration stop condition is met, thereby obtaining an optimized magnetic saturation scheme. Therefore, the problems that the integration level and portability of the system are reduced, the maintenance cost is increased, the measurement precision and repeatability are affected, the detection reliability is reduced and the like possibly caused by the fact that the permanent magnet system is large in size, high in system assembly and disassembly difficulty and limited in magnetic field uniformity in the prior art are solved.

Description

Technical Field

[0001] The present application relates to the technical field of electromagnetic equipment, and in particular to a yoke optimization method, device, equipment, medium and program for magnetic saturation compensation. Background Art

[0002] The design of the magnet system has always been a hot spot and difficulty in the development of power balances. In related technologies, the magnet system in the power balance can be divided into an electromagnet system and a permanent magnet system. The electromagnet system mainly generates a magnetic field through a coil, which has the advantage of adjustable magnetic field direction, but the magnetic field it generates is weak and generates severe heat during operation. The permanent magnet system generates a strong magnetic field, does not generate heat during operation, and has a small magnetic field coupling of the coil. Therefore, most power balances developed by institutions currently mainly use permanent magnet systems.

[0003] However, in the related art, due to the large size of the permanent magnet system, the integration and portability of the system may be affected. Due to the difficulty in assembling and disassembling the system, the complexity of daily maintenance and future upgrades increases, which increases maintenance costs and affects the normal operation of the system. In addition, due to the small uniform magnetic field area, it cannot meet the strict requirements for magnetic field uniformity, which may affect the accuracy and repeatability of the measurement, resulting in increased data errors and affecting the reliability of the detection results. Improvement is urgently needed. Summary of the invention

[0004] The present application provides a yoke optimization method for magnetic saturation compensation to solve the problems in the related art that, due to the large size of the permanent magnet system, the difficulty in assembling and disassembling the system and the limitation of magnetic field uniformity, the integration and portability of the system may be reduced, the maintenance cost may increase, the measurement accuracy and repeatability may be affected, and the detection reliability may be reduced.

[0005] The first aspect of the present application provides a yoke optimization method for magnetic saturation compensation, comprising the following steps: identifying a potential magnetic saturation area according to the magnetic flux distribution in the original magnet system, so as to configure at least one compensating magnet in the potential magnetic saturation area; calculating the internal magnetic induction intensity of the yoke near the compensating magnet based on a pre-established magnetic circuit model after magnetic saturation compensation, and judging whether multiple characteristic parameters of the compensating magnet and the compensation effect meet preset related conditions in combination with the internal magnetic induction intensity, and if the preset related conditions are met, obtaining key parameters related to the compensation effect; determining a preliminary magnetic saturation compensation scheme according to the magnetic circuit model and the key parameters, and iteratively optimizing the preliminary magnetic saturation compensation scheme using finite element simulation technology until a preset iteration stop condition is met, thereby obtaining an optimized magnetic saturation scheme.

[0006] Optionally, in one embodiment of the present application, the calculating the internal magnetic induction intensity of the yoke near the compensating magnet includes: calculating the magnetic induction intensity generated by the main magnet in the yoke and the compensating magnetic induction intensity generated by the compensating magnet in the yoke; calculating the difference between the magnetic induction intensity and the compensating magnetic induction intensity to obtain the internal magnetic induction intensity of the yoke near the compensating magnet.

[0007] Optionally, in one embodiment of the present application, the expression of the internal magnetic induction intensity of the magnetic yoke is:

[0008]

[0009] Among them, B is the internal magnetic induction intensity of the yoke, B1 is the magnetic induction intensity generated by the main magnet in the yoke, B2 is the compensation magnetic induction intensity generated by the compensation magnet in the yoke, μ0 is the magnetic permeability of vacuum, H C is the residual coercive force of the samarium cobalt material, S is the cross-sectional area of ​​the yoke perpendicular to the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, h is the cross-sectional area of ​​the air gap perpendicular to the direction of the magnetic flux, l1 is the thickness of the main magnet along the polarization direction, α is the leakage coefficient, δ1 is the length of the air gap along the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, and A2 is the cross-sectional area of ​​the compensation magnet perpendicular to the polarization direction.

[0010] Optionally, in one embodiment of the present application, before determining a preliminary magnetic saturation compensation scheme based on the magnetic circuit model and the key parameters, it also includes: verifying the effectiveness of the magnetic circuit model based on a pre-established finite element simulation model to obtain a verification result; based on the verification result, analyzing the regulatory effect of the key parameters on the compensation effect.

[0011] The second aspect of the present application provides a yoke optimization device for magnetic saturation compensation, including: a configuration module, used to identify potential magnetic saturation areas according to the magnetic flux distribution in the original magnet system, so as to configure at least one compensating magnet in the potential magnetic saturation area; an acquisition module, used to calculate the internal magnetic induction intensity of the yoke near the compensating magnet based on a pre-established magnetic circuit model after magnetic saturation compensation, and judge whether multiple characteristic parameters of the compensating magnet and the compensation effect meet preset related conditions in combination with the internal magnetic induction intensity, and when the preset related conditions are met, obtain key parameters related to the compensation effect; an optimization module, used to determine a preliminary magnetic saturation compensation scheme according to the magnetic circuit model and the key parameters, and iteratively optimize the preliminary magnetic saturation compensation scheme using finite element simulation technology until the preset iteration stop condition is met, thereby obtaining an optimized magnetic saturation scheme.

[0012] Optionally, in one embodiment of the present application, the acquisition module includes: a first calculation unit, used to calculate the magnetic induction intensity generated by the main magnet in the magnetic yoke and the compensation magnetic induction intensity generated by the compensation magnet in the magnetic yoke; a second calculation unit, used to calculate the difference between the magnetic induction intensity and the compensation magnetic induction intensity, and obtain the internal magnetic induction intensity of the magnetic yoke near the compensation magnet.

[0013] Optionally, in one embodiment of the present application, the expression of the internal magnetic induction intensity of the magnetic yoke is:

[0014]

[0015] Among them, B is the internal magnetic induction intensity of the yoke, B1 is the magnetic induction intensity generated by the main magnet in the yoke, B2 is the compensation magnetic induction intensity generated by the compensation magnet in the yoke, μ0 is the magnetic permeability of vacuum, H C is the residual coercive force of the samarium cobalt material, S is the cross-sectional area of ​​the yoke perpendicular to the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, h is the cross-sectional area of ​​the air gap perpendicular to the direction of the magnetic flux, l1 is the thickness of the main magnet along the polarization direction, α is the leakage coefficient, δ1 is the length of the air gap along the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, and A2 is the cross-sectional area of ​​the compensation magnet perpendicular to the polarization direction.

[0016] Optionally, in one embodiment of the present application, it also includes: a first verification module, used to verify the validity of the magnetic circuit model based on a pre-established finite element simulation model to obtain a verification result before determining a preliminary magnetic saturation compensation scheme based on the magnetic circuit model and the key parameters; a second verification module, used to analyze the regulatory effect of the key parameters on the compensation effect based on the verification result.

[0017] A third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the yoke optimization method for magnetic saturation compensation as described in the above embodiment.

[0018] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned yoke optimization method for magnetic saturation compensation.

[0019] A fifth aspect of the present application provides a computer program product, which, when executed, is used to implement the above-mentioned yoke optimization method for magnetic saturation compensation.

[0020] The embodiment of the present application can identify potential magnetic saturation areas by analyzing the magnetic flux distribution in the original magnet system, and configure the compensating magnet to calculate the internal magnetic induction intensity of the magnetic yoke near the compensating magnet based on the established magnetic circuit model, evaluate whether the characteristic parameters and compensation effect of the compensating magnet meet the preset conditions, and if the conditions are met, extract the key parameters related to the compensation effect, formulate a preliminary magnetic saturation compensation scheme, and use finite element simulation technology to iteratively optimize the scheme until the preset iteration stop condition is reached, thereby obtaining an optimized magnetic saturation compensation scheme, which can greatly reduce the magnetic flux and magnetic induction intensity in the magnetic yoke of the magnet system, avoid the situation of large-area saturation in the magnetic yoke, and effectively improve the performance and efficiency of the magnet system. Thus, the problems in the related art that the integration and portability of the system may be reduced, the maintenance cost may increase, and the measurement accuracy and repeatability may be affected, and the detection reliability may be reduced due to the large volume of the permanent magnet system, the difficulty of system assembly and disassembly, and the limitation of magnetic field uniformity may be solved.

[0021] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0023] Figure 1 A flowchart of a yoke optimization method for magnetic saturation compensation provided according to an embodiment of the present application;

[0024] Figure 2 A schematic diagram of the magnetic induction intensity distribution of a BIPM magnet according to an embodiment of the present application;

[0025] Figure 3 A schematic diagram of a magnetic saturation compensation principle for a quarter section of a magnet system according to an embodiment of the present application;

[0026] Figure 4 is a schematic diagram of a main magnet magnetic circuit model according to an embodiment of the present application;

[0027] Figure 5 is a schematic diagram of a magnetic circuit model of a compensation magnet according to an embodiment of the present application;

[0028] Figure 6 A schematic diagram of a curve of the magnetic induction intensity of the air gap magnetic field under the condition of compensating magnets with different cross-sectional widths according to an embodiment of the present application;

[0029] Figure 7 It is a schematic diagram of magnetic induction intensity cloud map simulation results of different compensation magnet setting schemes according to one embodiment of the present application;

[0030] Figure 8 Schematic diagram of distribution curve of magnetic induction intensity in outer magnetic yokes of different thicknesses according to one embodiment of the present application;

[0031] Fig. 9 Schematic diagram of distribution curve of magnetic induction intensity in upper magnetic yokes of different thicknesses according to one embodiment of the present application;

[0032] Fig.10 A block diagram of a yoke optimization device for magnetic saturation compensation provided according to an embodiment of the present application;

[0033] Fig.11 It is a schematic diagram of the structure of an electronic device provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0034] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0035] The following describes the yoke optimization method, device, equipment, medium and program for magnetic saturation compensation in embodiments of the present application with reference to the accompanying drawings.

[0036] Before introducing the yoke optimization method for magnetic saturation compensation in the embodiment of the present application, the relevant technology is first introduced in detail below. Among them, various types of production and economic activities in modern society are inseparable from a unified, stable and reliable measurement system. At the 26th International Conference on Weights and Measures, the International Bureau of Weights and Measures announced that 7 basic physical quantities will be defined by physical constants, thereby fully realizing the quantization of the international system of units. According to the latest definition of the International Bureau of Weights and Measures, the unit of mass kilogram is defined by Planck's constant h, and the current mainstream kilogram reproduction schemes include the silicon sphere method and the power balance method. Due to the great difficulty in processing the silicon spheres used in the silicon sphere method, the standard measurement units of various countries, such as the US NIST and the UK NPL, have successively carried out research on power balances.

[0037] In addition, the power balance can realize the association between mass units and electromagnetic energy, and is a key instrument for realizing the quantization of mass standards. Its working modes include force-weighing mode and motion mode. In force-weighing mode, current is passed through the coil in a uniform magnetic field. According to Ampere's law, the coil will be acted upon by a force in the magnetic field. When the Ampere force on the coil is balanced with the gravity of the weight being measured, we can obtain:

[0038] mg=BLI

[0039] Where m is the mass of the weight, g is the acceleration of gravity, B represents the magnetic flux density, I is the coil current, and L is the coil width. In the motion mode, the coil cuts the magnetic flux lines and generates an induced voltage. According to the law of electromagnetic induction:

[0040] U=BLv

[0041] Among them, U is the voltage across the coil, and v is the speed of the coil relative to the magnetic field. If the product BL of the magnetic field and the coil is exactly the same in the two modes, it can be eliminated and the mathematical model expression of the power balance is as follows:

[0042] mgv=UI

[0043] It is not difficult to find from the derivation process that the key condition to ensure the accuracy and reliability of the power balance measurement results is that BL remains unchanged in the two modes. Therefore, the design of the magnet system has always been a hot spot and difficulty in the development of power balances.

[0044] With regard to the above-mentioned related technologies, due to the large volume of the permanent magnet system, the difficulty of system assembly and disassembly, and the limitation of magnetic field uniformity, the system integration and portability may be reduced, the maintenance cost may increase, and the measurement accuracy and repeatability may be affected, and the detection reliability may be reduced. The present application provides a yoke optimization method for magnetic saturation compensation. In this method, the potential magnetic saturation area can be identified by analyzing the magnetic flux distribution in the original magnet system, and the compensating magnet can be configured to calculate the internal magnetic induction intensity of the yoke near the compensating magnet based on the established magnetic circuit model, and evaluate whether the characteristic parameters and compensation effect of the compensating magnet meet the preset conditions. If the conditions are met, the key parameters related to the compensation effect are extracted, and a preliminary magnetic saturation compensation scheme is formulated. The finite element simulation technology is used to iteratively optimize the scheme until the preset iteration stop condition is reached, thereby obtaining an optimized magnetic saturation compensation scheme, which can greatly reduce the magnetic flux and magnetic induction intensity in the yoke of the magnet system, avoid large-area saturation in the yoke, and effectively improve the performance and efficiency of the magnet system. Thereby, the problems in the related technology that the large size of the permanent magnet system, the difficulty in assembling and disassembling the system and the limitation of magnetic field uniformity may lead to reduced system integration and portability, increased maintenance costs, affected measurement accuracy and repeatability, and reduced detection reliability are solved.

[0045] Specifically, Figure 1 A schematic flow chart of a yoke optimization method for magnetic saturation compensation provided in an embodiment of the present application.

[0046] like Figure 1 As shown, the magnetic yoke optimization method for magnetic saturation compensation includes the following steps:

[0047] In step S101 , a potential magnetic saturation region is identified according to the magnetic flux distribution in the original magnet system, so as to configure at least one compensating magnet in the potential magnetic saturation region.

[0048] In the actual implementation process, the embodiment of the present application can analyze the position where magnetic saturation is likely to occur in the original magnet system, and configure the compensating magnet at this position. Specifically, the embodiment of the present application can use the finite element simulation software Ansoft Maxwell to analyze the position that is likely to occur in the original magnet system, and the simulation can obtain the following: Figure 2 The magnetic induction intensity distribution cloud diagram shown in FIG. Figure 2 It can be seen that magnetic saturation is likely to occur in places where the cross-sectional area of ​​the yoke is small (such as the parts of the outer yoke near the bottom and top), and local saturation points are also likely to occur at each corner.

[0049] It is worth noting that in the embodiment of the present application, the compensating magnet is placed where the cross-sectional area of ​​the outer yoke is smaller. In order to minimize the influence of the compensating magnet on the air gap magnetic field and obtain the maximum compensating magnetic flux, both ends of the compensating magnet can be selected to contact the yoke.

[0050] Optionally, the volume V of the magnet system is calculated as

[0051]

[0052] Where H is the height of the entire magnet system, r out is the radius of the magnet system.

[0053] In summary, the radius of the magnet system has a square relationship with the volume and a linear relationship with the height. Therefore, compared with reducing the height of the magnet system, reducing the radius of the magnet system can reduce the volume of the magnet system more. Therefore, it is possible to give priority to compensating the magnetic saturation of the outer yoke, that is, to place the compensation magnet on the outer yoke side first.

[0054] The embodiments of the present application help to improve the uniformity of the magnetic field through the reasonable arrangement of the compensation magnets, and the compensation magnets can specifically enhance the local magnetic field without increasing the burden on the main magnets, thereby improving the overall magnetic field strength of the system.

[0055] In step S102, based on the pre-established magnetic circuit model after magnetic saturation compensation, the internal magnetic induction intensity of the magnetic yoke near the compensating magnet is calculated, and combined with the internal magnetic induction intensity, it is judged whether multiple characteristic parameters of the compensating magnet and the compensation effect meet the preset related conditions. If the preset related conditions are met, the key parameters related to the compensation effect are obtained.

[0056] In some embodiments, the embodiments of the present application can calculate the internal magnetic induction intensity of the magnetic yoke near the compensation magnet based on the magnetic circuit theory, combined with Figure 3As shown, the magnetic circuit analysis modeling can be performed on a quarter section of a BIPM magnet. The specific steps are as follows:

[0057] First, the magnetic flux generated by the main magnet in the yoke is calculated.

[0058] Combination Figure 4 As shown in the figure, the magnetic flux generated by the main magnet returns to the S pole of the main magnet after passing through the yoke and air gap from its N pole. According to the flux continuity theorem and Ohm's law of magnetic circuit, we can get

[0059] H C1 l1=φ1(R yoke +R air +R m1 )

[0060] Among them, H C1 is the residual coercive force of the main magnet, l1 is the thickness of the main magnet along the polarization direction, φ1 is the main magnetic flux generated by the main magnet, R yoke , R air , R m1 They are the yoke reluctance, air gap reluctance and main magnet internal resistance respectively.

[0061] Since the yoke is made of ferromagnetic material with high magnetic permeability, the magnetic resistance of the yoke is much smaller than the internal resistance of the main magnet and the magnetic resistance of the air gap, so it can be ignored. The internal resistance of the main magnet and the magnetic resistance of the air gap can be calculated by the following formula:

[0062]

[0063] Among them, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, h is the cross-sectional area of ​​the air gap perpendicular to the magnetic flux direction, δ1 is the length of the air gap along the magnetic flux direction, μ r1 and μ0 are the magnetic permeabilities of the samarium cobalt magnet and vacuum respectively, and α is the leakage coefficient, which is related to the air gap shape, yoke material and structure.

[0064] Combining the above analysis, we can get the magnetic induction intensity b1 generated by the main magnet in the magnetic yoke as:

[0065]

[0066] Where S is the cross-sectional area of ​​the yoke perpendicular to the direction of magnetic flux.

[0067] Furthermore, combined with Figure 5 As shown, according to the same steps, the compensation magnetic induction intensity generated by the compensation magnet in the magnetic yoke can be calculated as:

[0068]

[0069] Among them, H C2is the residual coercive force of the compensation magnet, φ2 is the main magnetic flux generated by the compensation magnet, R m2 is the internal resistance of the compensation magnet, A2 is the cross-sectional area of ​​the compensation magnet perpendicular to the polarization direction, l2 is the thickness of the compensation magnet along the polarization direction, μ r2 To compensate for the magnetic permeability of the magnet.

[0070] In addition, the magnetic induction intensity B in the yoke can be obtained as:

[0071]

[0072] It is worth noting that the compensation magnet and the main magnet are both made of samarium cobalt material, so the residual coercive force and magnetic permeability of the two are the same; since the magnetic permeability of samarium cobalt material is very close to the magnetic permeability of vacuum, the two can be considered equal. Based on the above analysis, the magnetic induction intensity B of the yoke can be simplified.

[0073] Optionally, in one embodiment of the present application, the expression of the internal magnetic induction intensity of the magnetic yoke is:

[0074]

[0075] Among them, B is the internal magnetic induction intensity of the yoke, B1 is the magnetic induction intensity generated by the main magnet in the yoke, B2 is the compensation magnetic induction intensity generated by the compensation magnet in the yoke, μ0 is the magnetic permeability of vacuum, H C is the residual coercive force of the samarium cobalt material, S is the cross-sectional area of ​​the yoke perpendicular to the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, h is the cross-sectional area of ​​the air gap perpendicular to the direction of the magnetic flux, l1 is the thickness of the main magnet along the polarization direction, δ1 is the length of the air gap along the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, A2 is the cross-sectional area of ​​the compensation magnet perpendicular to the polarization direction, α is the leakage coefficient, and the leakage coefficient α can be calculated according to the relevant empirical formula, and can also be determined by comparing with the finite element simulation results. The embodiment of the present application can take α=1.3 by comparing the calculation results of the magnetic circuit model and the finite element model.

[0076] Of course, in some other embodiments, the embodiments of the present application can analyze the influence of the shape of the compensation magnet, material properties, etc. on the compensation effect based on the magnetic circuit model, and judge whether multiple characteristic parameters of the compensation magnet and the compensation effect meet the preset related conditions in combination with the internal magnetic induction intensity. According to the magnetic circuit model, it can be known that the compensation effect of the compensation magnet is only related to its cross-sectional area A2 perpendicular to the polarization direction. When When , the magnetic induction intensity in the yoke decreases as A2 increases; in particular, when When the magnetic induction intensity is 0, the yoke can be infinitely thin in theory; when When A2 increases, the magnetic induction intensity increases. The preset related conditions include but are not limited to the magnetic field intensity and distribution, magnetic field direction and size, etc.

[0077] The embodiment of the present application can accurately evaluate the compensation effect by precisely calculating the internal magnetic induction intensity of the yoke near the compensation magnet, thereby improving the efficiency of design and tuning. By combining the analysis results of the internal magnetic induction intensity, the key parameters that affect the compensation effect can be quickly identified, thereby effectively improving the performance of the magnetic circuit system and reducing resource waste and production costs.

[0078] Optionally, in one embodiment of the present application, the internal magnetic induction intensity of the yoke near the compensating magnet is calculated, including: calculating the magnetic induction intensity generated by the main magnet in the yoke and the compensating magnetic induction intensity generated by the compensating magnet in the yoke; calculating the difference between the magnetic induction intensity and the compensating magnetic induction intensity to obtain the internal magnetic induction intensity of the yoke near the compensating magnet.

[0079] The embodiment of the present application calculates the magnetic induction intensity generated by the main magnet and the compensation magnet in the yoke respectively, and further obtains the difference between the two to determine the actual magnetic induction intensity inside the yoke after compensation, which is conducive to precise control of the magnetic field distribution. The difference calculation directly reflects the effect of the compensation magnet, helps to quickly adjust the compensation strategy, achieve more accurate magnetic field compensation, effectively reduce unnecessary magnetic field fluctuations or unevenness, and enhance the adaptability and flexibility of the system.

[0080] In step S103, a preliminary magnetic saturation compensation scheme is determined according to the magnetic circuit model and key parameters, and the preliminary magnetic saturation compensation scheme is iteratively optimized using finite element simulation technology until a preset iteration stop condition is met to obtain an optimized magnetic saturation scheme.

[0081] Specifically, the embodiment of the present application can preliminarily determine the magnetic saturation compensation scheme based on the magnetic circuit model, and further optimize it based on finite element simulation to obtain the optimal magnetic saturation scheme. In particular, in order to reduce the volume of the magnet system as much as possible, the embodiment of the present application gives priority to magnetic saturation compensation for the outer yoke, followed by the upper and lower yokes, thereby combining Figure 6 and Figure 7 As shown, the embodiment of the present application compares 4 different configuration schemes of compensation magnets, and finally can select Figure 7 The solution shown on the far right can minimize the magnetic induction intensity of the outer yoke.

[0082] Furthermore, the embodiment of the present application can optimize the yoke size of the magnet system, reduce the volume and mass of the magnet system, and combine Figure 8 As shown in Table 1, the magnetic induction intensity inside the outer yoke is compared when the outer yoke has different thicknesses. Table 1 is a simulation result table of the magnetic induction intensity of the outer yoke.

[0083] Table 1

[0084] Thickness of the thinnest part of the outer yoke / mm Average magnetic induction intensity (uncompensated) / T Average magnetic induction intensity (after compensation) / T 17.5 0.705 0.424 12.5 1.009 0.607 7.5 1.724 1.036 5 2.617 1.572

[0085] In one embodiment of the present application, the yoke material is electrical pure iron, and its saturation magnetic induction intensity is generally about 1.5 to 2 T, so the thinnest thickness of the outer yoke after optimization is 7.5 mm. Fig. 9 As shown in Table 2, the magnetic induction intensity inside the upper and lower magnetic yokes at different thicknesses is obtained. Table 2 is a simulation result table of the magnetic induction intensity of the upper magnetic yoke.

[0086] Table 2

[0087] Upper yoke thickness / mm Average magnetic induction intensity (uncompensated) / T Average magnetic induction intensity (after compensation) / T 30 0.685 0.506 25 0.822 0.607 20 1.024 0.758 15 1.365 1.011

[0088] In addition, based on finite element simulation analysis, the embodiment of the present application can obtain the optimized size of the yoke, as shown in Table 3, which is a comparison table of key geometric parameters of related technologies and the present application.

[0089] Table 3

[0090] Geometric parameters Related technologies This application Thinnest outer yoke thickness (mm) 17.5 7.5 Upper and lower yoke thickness (mm) 30 15 Overall outer diameter (mm) 220 200 Overall height (mm) 180 150

[0091] Compared with related technologies, the overall volume of the optimized magnet system is reduced by 31.13% and the mass is reduced by 14.16kg.

[0092] In summary, from the simulation results and the final optimization scheme, it can be seen that the yoke optimization method of the BIPM type magnet system based on the magnetic saturation compensation principle proposed in this application can reduce the size of the external yoke and reduce the mass of the magnet system without changing the internal structure of the magnet system, and the yoke is still in an unsaturated state after reduction. In addition, under the condition that the cross-sectional width of the compensation magnet is appropriate, the use of this method has little effect on the properties of the air gap magnetic field, and can effectively reduce the volume and mass of the BIPM type magnet system in the power balance, which has important guiding significance for the miniaturization and lightweight of the power balance.

[0093] Optionally, in one embodiment of the present application, before determining a preliminary magnetic saturation compensation scheme based on the magnetic circuit model and key parameters, it also includes: verifying the validity of the magnetic circuit model based on a pre-established finite element simulation model to obtain a verification result; based on the verification result, analyzing the regulatory effect of the key parameters on the compensation effect.

[0094] Specifically, the embodiments of the present application can verify the validity of the magnetic circuit model through finite element simulation, and verify and analyze the influence of key parameters. By building a BIPM-type magnet system simulation model with a compensating magnet added in Ansoft Maxwell software, changing the cross-sectional area of ​​the compensating magnet, and recording the data of the magnetic induction intensity in the yoke, the change of the air gap magnetic field can be observed. As shown in Table 4, by analyzing the calculation results of the magnetic circuit model and the finite element model, it can be seen that the results obtained by the two are similar and the change trends are the same, which verifies the validity of the obtained magnetic circuit model. Among them, Table 4 is a comparison table of the calculation results of the magnetic circuit model and the finite element model.

[0095] Table 4

[0096] Thickness of the thinnest part of the outer yoke / mm Calculate magnetic induction intensity / T Simulated magnetic induction intensity / T 17.5 0.425 0.424 12.5 0.595 0.607 7.5 0.992 1.036 5 1.489 1.572

[0097] Therefore, the finite element simulation results show that when the cross-sectional area of ​​the compensation magnet is large and exceeds the inner surface of the yoke, it will have a greater impact on the uniform area of ​​the air gap magnetic field and reduce the magnetic induction intensity in the air gap; when the cross-sectional area is small, a new saturation point will be generated where the compensation magnet contacts the inner surface of the yoke. Therefore, it should be ensured that the inside of the yoke remains flat after the compensation magnet is configured. That is, if the thickness difference between the thicker area and the thinner area of ​​the outer yoke is recorded as Δx, the cross-sectional width of the compensation magnet should be:

[0098]

[0099] The embodiment of the present application verifies the validity of the magnetic circuit model based on a pre-established finite element simulation model, and analyzes the regulatory effect of key parameters on the compensation effect, which is conducive to reducing the risk and cost of failure, and can systematically optimize the compensation scheme to ensure the optimization of the compensation effect, achieve the required magnetic field uniformity and strength, and effectively enhance the reliability and accuracy of the design.

[0100] According to the magnetic saturation compensation yoke optimization method proposed in the embodiment of the present application, the potential magnetic saturation area can be identified by analyzing the magnetic flux distribution in the original magnet system, and the compensating magnet is configured to calculate the internal magnetic induction intensity of the magnetic yoke near the compensating magnet based on the established magnetic circuit model, and evaluate whether the characteristic parameters and compensation effect of the compensating magnet meet the preset conditions. If the conditions are met, the key parameters related to the compensation effect are extracted, a preliminary magnetic saturation compensation scheme is formulated, and the scheme is iteratively optimized using finite element simulation technology until the preset iteration stop condition is reached, thereby obtaining an optimized magnetic saturation compensation scheme, which can greatly reduce the magnetic flux and magnetic induction intensity in the magnetic yoke of the magnet system, avoid the situation of large-area saturation in the magnetic yoke, and effectively improve the performance and efficiency of the magnet system. Thus, the problems in the related art that the integration and portability of the system may be reduced, the maintenance cost may increase, the measurement accuracy and repeatability may be affected, and the detection reliability may be reduced due to the large volume of the permanent magnet system, the difficulty of system assembly and disassembly, and the limitation of magnetic field uniformity may be solved.

[0101] Next, the yoke optimization device for magnetic saturation compensation proposed in accordance with an embodiment of the present application will be described with reference to the accompanying drawings.

[0102] Fig.10 It is a block diagram of a yoke optimization device for magnetic saturation compensation according to an embodiment of the present application.

[0103] like Fig.10 As shown, the magnetic yoke optimization device 10 for magnetic saturation compensation includes: a configuration module 100, an acquisition module 200 and an optimization module 300.

[0104] Specifically, the configuration module 100 is used to identify a potential magnetic saturation region according to the magnetic flux distribution in the original magnet system, so as to configure at least one compensating magnet in the potential magnetic saturation region.

[0105] The acquisition module 200 is used to calculate the internal magnetic induction intensity of the magnetic yoke near the compensation magnet based on the pre-established magnetic circuit model after magnetic saturation compensation, and to judge whether multiple characteristic parameters of the compensation magnet and the compensation effect meet preset related conditions in combination with the internal magnetic induction intensity. When the preset related conditions are met, key parameters related to the compensation effect are obtained.

[0106] The optimization module 300 is used to determine a preliminary magnetic saturation compensation scheme according to the magnetic circuit model and key parameters, and iteratively optimize the preliminary magnetic saturation compensation scheme using finite element simulation technology until a preset iteration stop condition is met to obtain an optimized magnetic saturation scheme.

[0107] Optionally, in one embodiment of the present application, the acquisition module 200 includes: a first calculation unit and a second calculation unit.

[0108] The first calculation unit is used to calculate the magnetic induction intensity generated by the main magnet in the magnetic yoke and the compensation magnetic induction intensity generated by the compensation magnet in the magnetic yoke;

[0109] The second calculation unit is used to calculate the difference between the magnetic induction intensity and the compensation magnetic induction intensity to obtain the internal magnetic induction intensity of the magnetic yoke near the compensation magnet.

[0110] Optionally, in one embodiment of the present application, the expression of the internal magnetic induction intensity of the magnetic yoke is:

[0111]

[0112] Among them, B is the internal magnetic induction intensity of the yoke, B1 is the magnetic induction intensity generated by the main magnet in the yoke, B2 is the compensation magnetic induction intensity generated by the compensation magnet in the yoke, μ0 is the magnetic permeability of vacuum, H C is the residual coercive force of the samarium cobalt material, S is the cross-sectional area of ​​the yoke perpendicular to the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, h is the cross-sectional area of ​​the air gap perpendicular to the direction of the magnetic flux, l1 is the thickness of the main magnet along the polarization direction, α is the leakage coefficient, δ1 is the length of the air gap along the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, and A2 is the cross-sectional area of ​​the compensation magnet perpendicular to the polarization direction.

[0113] Optionally, in one embodiment of the present application, it also includes: a first verification module and a second verification module.

[0114] The first verification module is used to verify the effectiveness of the magnetic circuit model based on a pre-established finite element simulation model to obtain a verification result before determining a preliminary magnetic saturation compensation scheme according to the magnetic circuit model and key parameters;

[0115] The second verification module is used to analyze the regulatory effect of the key parameters on the compensation effect based on the verification results.

[0116] It should be noted that the aforementioned explanation of the embodiment of the yoke optimization method for magnetic saturation compensation is also applicable to the yoke optimization device for magnetic saturation compensation of this embodiment, and will not be repeated here.

[0117] According to the yoke optimization device for magnetic saturation compensation proposed in the embodiment of the present application, the potential magnetic saturation area can be identified by analyzing the magnetic flux distribution in the original magnet system, and the compensating magnet is configured to calculate the internal magnetic induction intensity of the yoke near the compensating magnet based on the established magnetic circuit model, and evaluate whether the characteristic parameters and compensation effect of the compensating magnet meet the preset conditions. If the conditions are met, the key parameters related to the compensation effect are extracted, a preliminary magnetic saturation compensation scheme is formulated, and the scheme is iteratively optimized using finite element simulation technology until the preset iteration stop condition is reached, thereby obtaining an optimized magnetic saturation compensation scheme, which can greatly reduce the magnetic flux and magnetic induction intensity in the yoke of the magnet system, avoid the situation of large-area saturation in the yoke, and effectively improve the performance and efficiency of the magnet system. Thus, the problems in the related art that the integration and portability of the system may be reduced, the maintenance cost may increase, the measurement accuracy and repeatability may be affected, and the detection reliability may be reduced due to the large volume of the permanent magnet system, the difficulty of system assembly and disassembly, and the limitation of magnetic field uniformity may be solved.

[0118] Fig.11 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0119] A memory 1101 , a processor 1102 , and a computer program stored in the memory 1101 and executable on the processor 1102 .

[0120] When the processor 1102 executes the program, the yoke optimization method for magnetic saturation compensation provided in the above embodiment is implemented.

[0121] Furthermore, the electronic device further comprises:

[0122] The communication interface 1103 is used for communication between the memory 1101 and the processor 1102 .

[0123] The memory 1101 is used to store computer programs that can be executed on the processor 1102 .

[0124] The memory 1101 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0125] If the memory 1101, the processor 1102 and the communication interface 1103 are implemented independently, the communication interface 1103, the memory 1101 and the processor 1102 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig.11 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0126] Optionally, in a specific implementation, if the memory 1101, the processor 1102 and the communication interface 1103 are integrated on a chip, the memory 1101, the processor 1102 and the communication interface 1103 can communicate with each other through an internal interface.

[0127] The processor 1102 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0128] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned yoke optimization method for magnetic saturation compensation.

[0129] An embodiment of the present application also provides a computer program product, which can run computer instructions. When the computer instructions are executed by a processor, the yoke optimization method for magnetic saturation compensation as described above is implemented.

[0130] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0131] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0132] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0133] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0134] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of multiple of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0135] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0136] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0137] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A yoke optimization method for magnetic saturation compensation, characterized in that: The following steps are involved: identifying a potential magnetic saturation region according to the magnetic flux distribution in the original magnet system, so as to configure at least one compensating magnet in the potential magnetic saturation region; Based on the pre-established magnetic circuit model after magnetic saturation compensation, the internal magnetic induction intensity of the magnetic yoke near the compensation magnet is calculated, and combined with the internal magnetic induction intensity, a plurality of characteristic parameters of the compensation magnet and the compensation effect are judged to determine whether they meet the preset related conditions. If the preset related conditions are met, the key parameters related to the compensation effect are obtained; A preliminary magnetic saturation compensation scheme is determined according to the magnetic circuit model and the key parameters, and the preliminary magnetic saturation compensation scheme is iteratively optimized using finite element simulation technology until a preset iteration stop condition is met to obtain an optimized magnetic saturation scheme.

2. The method according to claim 1, characterized in that: The calculating the internal magnetic induction intensity of the magnetic yoke near the compensating magnet comprises: Calculating the magnetic induction intensity generated by the main magnet in the magnetic yoke and the compensation magnetic induction intensity generated by the compensation magnet in the magnetic yoke; The difference between the magnetic induction intensity and the compensation magnetic induction intensity is calculated to obtain the internal magnetic induction intensity of the magnetic yoke near the compensation magnet.

3. The method according to claim 2, characterized in that The expression of the internal magnetic induction intensity of the yoke is: Among them, B is the internal magnetic induction intensity of the yoke, B1 is the magnetic induction intensity generated by the main magnet in the yoke, B2 is the compensation magnetic induction intensity generated by the compensation magnet in the yoke, μ0 is the magnetic permeability of vacuum, H C is the residual coercive force of the samarium cobalt material, S is the cross-sectional area of ​​the yoke perpendicular to the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, h is the cross-sectional area of ​​the air gap perpendicular to the direction of the magnetic flux, l1 is the thickness of the main magnet along the polarization direction, α is the leakage coefficient, δ1 is the length of the air gap along the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, and A2 is the cross-sectional area of ​​the compensation magnet perpendicular to the polarization direction.

4. The method according to claim 1, characterized in that Before determining a preliminary magnetic saturation compensation scheme according to the magnetic circuit model and the key parameters, the method further includes: Verifying the effectiveness of the magnetic circuit model based on a pre-established finite element simulation model to obtain a verification result; Based on the verification results, the regulatory effect of the key parameters on the compensation effect is analyzed.

5. A yoke optimization device for magnetic saturation compensation, characterized in that: include: A configuration module, for identifying a potential magnetic saturation region according to the magnetic flux distribution in the original magnet system, so as to configure at least one compensation magnet in the potential magnetic saturation region; An acquisition module, for calculating the internal magnetic induction intensity of the magnetic yoke near the compensation magnet based on a pre-established magnetic circuit model after magnetic saturation compensation, and judging whether multiple characteristic parameters of the compensation magnet and the compensation effect meet preset related conditions in combination with the internal magnetic induction intensity, and acquiring key parameters related to the compensation effect when the preset related conditions are met; The optimization module is used to determine a preliminary magnetic saturation compensation scheme according to the magnetic circuit model and the key parameters, and iteratively optimize the preliminary magnetic saturation compensation scheme using finite element simulation technology until a preset iteration stop condition is met to obtain an optimized magnetic saturation scheme.

6. The device according to claim 5, characterized in that The acquisition module comprises: A first calculation unit, used for calculating the magnetic induction intensity generated by the main magnet in the magnetic yoke and the compensation magnetic induction intensity generated by the compensation magnet in the magnetic yoke; The second calculation unit is used to calculate the difference between the magnetic induction intensity and the compensation magnetic induction intensity to obtain the internal magnetic induction intensity of the magnetic yoke near the compensation magnet.

7. The device according to claim 6, characterized in that The expression of the internal magnetic induction intensity of the yoke is: Among them, B is the internal magnetic induction intensity of the yoke, B1 is the magnetic induction intensity generated by the main magnet in the yoke, B2 is the compensation magnetic induction intensity generated by the compensation magnet in the yoke, μ0 is the magnetic permeability of vacuum, H C is the residual coercive force of the samarium cobalt material, S is the cross-sectional area of ​​the yoke perpendicular to the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, h is the cross-sectional area of ​​the air gap perpendicular to the direction of the magnetic flux, l1 is the thickness of the main magnet along the polarization direction, α is the leakage coefficient, δ1 is the length of the air gap along the direction of the magnetic flux, A1 is the cross-sectional area of ​​the main magnet perpendicular to the polarization direction, and A2 is the cross-sectional area of ​​the compensation magnet perpendicular to the polarization direction.

8. The device according to claim 5, characterized in that Also includes: A first verification module is used to verify the effectiveness of the magnetic circuit model based on a pre-established finite element simulation model to obtain a verification result before determining a preliminary magnetic saturation compensation scheme according to the magnetic circuit model and the key parameters; The second verification module is used to analyze the regulating effect of the key parameter on the compensation effect based on the verification result.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the magnetic yoke optimization method for magnetic saturation compensation as described in any one of claims 1 to 4.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the yoke optimization method for magnetic saturation compensation as described in any one of claims 1 to 4.

11. A computer program product, comprising a computer program, characterized in that The computer program is executed to implement the yoke optimization method for magnetic saturation compensation according to any one of claims 1 to 4.

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