Simulation method for coupling of magnetic field and residual magnetic moment in inertial sensor

Abstract

The invention relates to the technical field of inertial sensors, in particular to a simulation method for coupling of a magnetic field and a residual magnetic moment in an inertial sensor, and solves the defect that the influence of magnetic disturbance cannot be accurately estimated on the ground by building a finite element simulation system to quantitatively analyze the influence caused by coupling of the magnetic field and the residual magnetic moment in the inertial sensor. The coupling effect of the magnetic field and the residual magnetic moment is accurately simulated, and the precision of the inertial sensor is improved.

Description

Technical Field

[0001] The present application relates to the technical field of inertial sensors, and in particular to a simulation method for coupling a magnetic field and a residual magnetic moment in an inertial sensor. Background Art

[0002] In space-based gravitational wave detection, the magnetic field couples the magnetic susceptibility and remanent magnetic moment of the inertial reference of an inertial sensor. Changes in the magnetic field induce magnetic forces at the inertial reference's location. These forces are difficult to distinguish from the forces caused by gravitational waves, thus interfering with the geodesic motion of the inertial reference. Furthermore, the magnetic field acting on the inertial reference is susceptible to interference from the Earth's magnetic field when measured on the ground, making direct measurement difficult. Therefore, accurate magnetic simulation is essential when designing inertial sensors.

[0003] This application focuses on the coupling effect between the magnetic field and the magnetic moment of the inertial reference. Through precise model simulation, it deeply studies the magnetic noise to which the inertial reference in the inertial sensor is subjected, solves the defect that cannot be directly measured on the ground, and provides a simulation method that can accurately estimate the ground. Summary of the Invention

[0004] This application provides a simulation method for the coupling of magnetic field and residual magnetic moment in an inertial sensor, which solves the defect that the impact of magnetic disturbance on the ground cannot be accurately estimated, and accurately simulates the coupling effect of magnetic field and residual magnetic moment.

[0005] To achieve the above objectives, the present application provides a simulation method for the coupling of magnetic field and residual magnetic moment in an inertial sensor, comprising the following steps: Step 1: Constructing a finite element geometric model based on the mechanism analysis of the coupling effect between magnetic field and residual magnetic moment; Step 2: Designing a simulation model, analyzing the input parameters required for the simulation, and determining the physical field interface and boundary conditions; Step 3: Finite element meshing, dividing the finite element mesh by comprehensively weighing the computational time and computational accuracy required for the simulation model; Step 4: Executing simulation calculations to simulate the coupling of magnetic field and residual magnetic moment; Step 5: Processing the simulation results, analyzing the simulation results, evaluating the impact of the coupling of magnetic field and residual magnetic moment on the performance of the inertial sensor, and proposing improvement solutions.

[0006] Furthermore, the finite element geometric model includes a test mass, a capacitor plate and a thermistor with a negative temperature coefficient characteristic, wherein: the test mass is a cubic configuration, made of a gold-platinum alloy material, and the surface is gold-plated; the capacitor plate is a cubic configuration, made of a molybdenum material, and the surface is gold-plated; the capacitor plate includes 12 sensing electrodes and 6 injection electrodes, the sensing electrodes and the injection electrodes are symmetrically distributed about the center, the sensing electrodes are distributed on both sides, and the injection electrodes are set in the center; the thermistor with a negative temperature coefficient characteristic is a cylindrical configuration, 8 of which are set, and are evenly symmetrically distributed along the x-axis direction of the outer side of the capacitor plate, and the distance between each side and the test mass is 13 mm.

[0007] Furthermore, in step 2, the magnetic field and no current physical field interfaces of COMSOL are used to establish the simulation model.

[0008] Furthermore, in step 2, the boundary conditions include the total magnetic field constant, the interplanetary field fluctuation, the residual magnetic moment of the thermistor with negative temperature coefficient characteristics, the total magnetic field gradient fluctuation, and the magnetic susceptibility and residual magnetic moment of the test mass.

[0009] Furthermore, in step 3, the computational time and computational accuracy required for the simulation model are comprehensively weighed, the mesh element quality is set, the mesh refinement level is selected, and the analysis step of the transient solver is created.

[0010] Furthermore, in step 4, COMSOL finite element simulation software is used to perform simulation calculations and simulate the coupling disturbance of the magnetic field and the residual magnetic moment.

[0011] Furthermore, in step 5, the simulation results are analyzed and processed to obtain a magnetic noise spectral density curve of the proof mass, and to evaluate the noise impact caused by the coupling of the magnetic field and the residual magnetic moment on the proof mass of the inertial sensor.

[0012] The present application provides a simulation method for coupling magnetic field and residual magnetic moment in an inertial sensor, which has the following beneficial effects:

[0013] This application builds a finite element simulation system to quantitatively analyze the effects of the coupling between the magnetic field and the residual magnetic moment in the inertial sensor, thereby solving the problem of the inability to accurately predict the effects of magnetic disturbances on the ground, accurately simulating the coupling effect between the magnetic field and the residual magnetic moment, and improving the accuracy of the inertial sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings that constitute part of this application are used to provide a further understanding of this application and make other features, objects and advantages of this application more apparent. The illustrative embodiment drawings of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application. In the drawings:

[0015] Figure 1Schematic diagram of the geometric configuration of the coupling between the magnetic field and the residual magnetic moment provided in an embodiment of the present application;

[0016] Figure 2 Schematic diagram of a simulation system for coupling magnetic field and residual magnetic moment according to an embodiment of the present application;

[0017] Figure 3 is a schematic diagram of the magnetic field environment around the test mass provided in accordance with an embodiment of the present application;

[0018] Figure 4 Schematic diagram of a magnetic noise spectral density curve of the inspection mass provided in an embodiment of the present application. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0020] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] In this application, terms such as "upper," "lower," "left," "right," "front," "back," "top," "bottom," "inner," "outer," "center," "vertical," "horizontal," "transverse," and "longitudinal" indicate positions or locations based on the positions or locations shown in the accompanying drawings. These terms are primarily intended to better describe this application and its embodiments and are not intended to limit the devices, elements, or components indicated to having a specific orientation, or to being constructed or operated in a specific orientation.

[0022] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to indicate a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0023] Additionally, the term "plurality" shall mean two or more.

[0024] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] This application provides a simulation method for the coupling between the magnetic field and the residual magnetic moment in an inertial sensor. A geometric model is constructed based on the basic structure of a magnetic diagnostic subsystem. A finite element simulation system is built to quantitatively analyze the effects of the coupling between the magnetic field and the residual magnetic moment in the inertial sensor. This method addresses the inability to accurately estimate the effects of magnetic disturbances on the ground and accurately simulates the coupling effect between the magnetic field and the residual magnetic moment. The method specifically includes the following steps:

[0026] Step 1: Construct a finite element geometric model based on the mechanism analysis of the coupling effect between the magnetic field and the residual magnetic moment;

[0027] Specifically, magnetic noise is the result of the coupling between the residual magnetic moment and the surrounding magnetic field. Therefore, this application mainly studies and analyzes the source and effect of the wave force; this application is based on the mechanism analysis of the coupling effect of the magnetic field and the residual magnetic moment, and refers to the basic structure of the magnetic diagnostic subsystem to realize the construction of a finite element geometric model of the coupling effect of the magnetic field and the residual magnetic moment.

[0028] More specifically, Figure 1 As shown, in the embodiment of the present application, when constructing the finite element geometric model, the finite element geometric model includes a test mass (TM), a capacitor plate (EH) and a thermistor with a negative temperature coefficient characteristic. The test mass is preferably a 46 mm cubic configuration, made of an alloy ratio of 73% gold and 27% platinum, and the magnetic susceptibility satisfies |χ|≤10 -5, weighing 1.73kg, with a gold-plated surface to provide high reflectivity for intersatellite links; the capacitor plate is a cubic configuration, made of molybdenum material, and gold-plated on the surface; the capacitor plate includes 12 sensing electrodes and 6 injection electrodes, the sensing electrodes and injection electrodes are symmetrically distributed around the center, the sensing electrodes are distributed on both sides, and the injection electrodes are set in the center; the thermistor with negative temperature coefficient characteristics is a cylindrical configuration, 8 of which are set, evenly and symmetrically distributed along the x-axis direction of the outer side of the capacitor plate, and the distance from the test mass on each side is 13mm. In addition, in the design process of the inertial sensor, the use of permanent magnets should be avoided as much as possible, and non-magnetic processing materials should be used first. At the same time, the introduction of residual magnetism should be avoided or reduced during the processing process, and the residual magnetism around the inertial sensor should be monitored without introducing magnetic interference.

[0029] Step 2: Design a simulation model, such as Figure 2 As shown, analyze the input parameters required for simulation and determine the physical field interface and boundary conditions;

[0030] Specifically, in the coupling effect between magnetic field and residual magnetic moment, since the magnetic field problem of current flow is not involved, the "Magnetic Field, No Current" physics interface of COMSOL is used to simulate this coupling effect; and the relevant finite element boundary conditions are set in the "Magnetic Field, No Current" physics interface. Among them, the magnetic field mainly includes the interplanetary magnetic field and the spacecraft magnetic field. The interplanetary magnetic field is set through the input module, and the test mass is in a uniformly distributed interplanetary magnetic field. The spacecraft magnetic field constant mainly comes from the cold gas inside the spacecraft, which is the permanent magnet in the propulsion system. Its value is about 2×10 -6 T, the constant amount of the spacecraft magnetic field gradient, is mainly determined by the residual magnetic moment of the thermistor itself with the negative temperature coefficient characteristic.

[0031] More specifically, Figure 3 As shown in the figure, the distribution of the total magnetic field around the test mass is mainly affected by its own magnetic properties and the externally applied magnetic field or magnetic moment carrier. In this case, parameters such as the magnetic permeability of the material are set to describe the magnetic properties of the material. At the same time, the test mass is in a uniformly distributed interplanetary magnetic field. With reference to the measured data, the average interplanetary magnetic field and its fluctuations are set. In addition, the thermistor material characteristics with negative temperature coefficient characteristics in the thermal diagnostic subsystem have residual magnetic moments, and their own magnetic properties will produce a constant average local magnetic field gradient around the test mass. By setting the above boundary conditions, the average local magnetic field gradient generated by the magnetic moment carrier around the test mass and its distribution state after coupling with the residual magnetic moment of the test mass are constructed, and the influence of the mutual coupling between the total magnetic field environment and the residual magnetic moment of the test mass is analyzed. The specific boundary condition parameters are shown in Table 1:

[0032]

[0033]

[0034] Table 1 Boundary condition parameter settings of the simulation model

[0035] Step 3: Finite element mesh division: comprehensively weigh the computational time and computational accuracy required for the simulation model and divide the finite element mesh;

[0036] Specifically, the computational accuracy and computational time required for the magnetic field and current-free physics interfaces are weighed against each other. The finite element mesh quality is set, the "fine" meshing level is used, and the analysis step of the transient solver is created.

[0037] Step 4: Execute simulation calculations to simulate the coupling of the magnetic field and the residual magnetic moment; use COMSOL finite element simulation software to perform simulation calculations to simulate the coupling perturbation of the magnetic field and the residual magnetic moment.

[0038] Step 5: Process the simulation results, analyze the simulation results, evaluate the impact of the coupling between the magnetic field and the residual magnetic moment on the performance of the inertial sensor, and propose improvement plans.

[0039] Specifically, by analyzing and processing the simulation data results, the magnetic noise spectrum density curve of the test mass is obtained, such as Figure 4 As shown, the noise impact caused by the coupling of magnetic field and residual magnetic moment on the proof quality of inertial sensor is evaluated, and improvement measures are proposed for the design of schemes affecting this coupling effect in inertial sensors.

[0040] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A simulation method for coupling magnetic field and residual magnetic moment in an inertial sensor, characterized in that: The steps include: Step 1: Construct a finite element geometric model based on the mechanism analysis of the coupling effect between the magnetic field and the residual magnetic moment; Step 2: Design the simulation model, analyze the input parameters required for simulation, and determine the physical field interface and boundary conditions; Step 3: Finite element mesh division: comprehensively weigh the computational time and computational accuracy required for the simulation model and divide the finite element mesh; Step 4: Execute simulation calculations to simulate the coupling between the magnetic field and the residual magnetic moment; Step 5: Process the simulation results, analyze the simulation results, evaluate the impact of the coupling between the magnetic field and the residual magnetic moment on the performance of the inertial sensor, and propose improvement plans.

2. The method for simulating the coupling of magnetic field and residual magnetic moment in an inertial sensor according to claim 1, characterized in that: The finite element geometry includes the test mass, capacitor plates, and a thermistor with a negative temperature coefficient characteristic, where: The test mass is in a cubic configuration, made of a gold-platinum alloy material, and the surface is gold-plated; The capacitor plate is in a cubic configuration, made of molybdenum material, and the surface is gold-plated; The capacitor plate includes 12 sensing electrodes and 6 injection electrodes, and the sensing electrodes and the injection electrodes are symmetrically distributed around the center, with the sensing electrodes distributed on both sides and the injection electrodes arranged in the center; The negative temperature coefficient thermistor is cylindrical in configuration, 8 of which are arranged evenly and symmetrically distributed along the x-axis direction outside the capacitor plate, with each side being 13 mm away from the test mass.

3. The method for simulating the coupling of magnetic field and residual magnetic moment in an inertial sensor according to claim 2, characterized in that: In step 2, the magnetic field and no current physical field interfaces of COMSOL are used to establish the simulation model.

4. The method for simulating the coupling of magnetic field and residual magnetic moment in an inertial sensor according to claim 3, characterized in that: In step 2, the boundary conditions include the constant of the total magnetic field, the fluctuation of the interplanetary field, the residual magnetic moment of the thermistor with negative temperature coefficient characteristics, the fluctuation of the total magnetic field gradient, and the magnetic susceptibility and residual magnetic moment of the test mass.

5. The method for simulating the coupling of magnetic field and residual magnetic moment in an inertial sensor according to claim 4, characterized in that: In step 3, the computational time and accuracy required for the simulation model are comprehensively weighed, the mesh element quality is set, the mesh refinement level is selected, and the analysis step of the transient solver is created.

6. The method for simulating the coupling of magnetic field and residual magnetic moment in an inertial sensor according to claim 5, characterized in that: In step 4, COMSOL finite element simulation software is used to perform simulation calculations and simulate the coupling disturbance of the magnetic field and the residual magnetic moment.

7. The method for simulating the coupling of magnetic field and residual magnetic moment in an inertial sensor according to claim 6, characterized in that: In step 5, the simulation results are analyzed and processed to obtain a magnetic noise spectral density curve of the proof mass, and the noise impact caused by the coupling of the magnetic field and the residual magnetic moment on the inertial sensor proof mass is evaluated.

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