A method for predicting conductive chip motion based on microgravity and multi-field coupling

Abstract

A conductive abrasive movement prediction method based on microgravity and multi-field coupling belongs to the technical field of spacecraft conductive ring abrasive dynamics, and the implementation method is as follows: the physical description of the conductive ring is established, and the 1 / 2 disc type slip ring is selected as the research object; the spatial physical field modeling of the conductive ring is carried out based on the differential form of Maxwell equation group, and the electric field and the magnetic field of the conductive ring system are solved; the force analysis of the abrasive is carried out in the body coordinate system, the force includes the earth gravity, the electric field force, the Lorentz force, and the Coriolis force, the centrifugal force and the Euler force which need to be considered because the body coordinate system is a non-inertial system, wherein the magnetic flux density in the Lorentz force includes the earth magnetic field and the magnetic field generated by the conductive ring electrification; based on Newton's second law, the position vector conversion relationship between the body coordinate system and the inertial coordinate system is combined, and the abrasive dynamics equation in the body coordinate system is derived; the motion trajectory of the single abrasive is obtained by solving the dynamics equation.

Description

Technical Field

[0001] This invention belongs to the field of spacecraft conductive ring wear debris dynamics technology, and relates to a method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling. Background Technology

[0002] Conductive rings are widely used in core spacecraft components such as solar panel drive mechanisms (SADA) and control moment gyroscopes (CMG). They are crucial functional components in spacecraft power and distribution systems, but also among the high-risk components. The wear debris generated by conductive rings during long-term operation can accumulate due to directional movement, increasing the risk of internal arcing and causing multiple spacecraft malfunctions and losses exceeding hundreds of millions of yuan. On October 31, 2022, a conductive ring wear debris test device for the space station's aerospace technology experiment, launched into orbit along with the aerospace basic test cabinet aboard the Mengtian experimental module of the space station, successfully conducted on-orbit observation experiments on conductive ring wear debris, achieving my country's first on-orbit observation of the generation process and clustering phenomenon of conductive ring wear debris.

[0003] In terrestrial environments, current research on the kinematic characteristics of conductive ring wear debris primarily relies on COMSOL simulation software. However, existing simulations depend on experiments under constant gravity, which cannot extrapolate the on-orbit migration path and aggregation behavior of wear debris under real-world microgravity conditions, nor can they accurately assess the risk of arcing within the device. Summary of the Invention

[0004] To address the safety hazards to spacecraft caused by debris accumulation, this invention provides a method for predicting the motion of conductive debris based on microgravity and multi-field coupling. It establishes a physical description of a conductive ring, selecting a 1 / 2 disc slip ring as the research object. Based on the differential form of Maxwell's equations, it models the space physical field of the conductive ring, solving for the electric and magnetic fields of the system. Considering the coupling effects of microgravity, electric force, Lorentz force, and inertial force, it models and analyzes the motion of debris within the conductive ring structure, establishing the on-orbit dynamic equations of conductive debris under microgravity and complex electromagnetic field coupling. This further reveals the law governing the migration of debris to the outer wall of the slip ring and the formation of an accumulation layer driven by the electric field, thus solving the problem of predicting debris accumulation risks.

[0005] The objective of this invention is achieved through the following technical solutions.

[0006] This invention discloses a method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling, comprising the following steps:

[0007] Step 1: Taking the conductive ring as the object, conductive rings are divided into disc-type conductive rings and cylindrical conductive rings. The channels of a disc-type conductive ring are arranged parallel to each other on a disc-shaped plane, and the overall shape is a flattened cylinder. The channels of a cylindrical conductive ring are arranged side-by-side on the outer surface of a cylinder, and the overall shape is a long, narrow cylinder. Based on the axial symmetry of the conductive ring, a 1 / 2 conductive ring is selected as the analysis object; the average mass m and charge q of the wear debris particles are determined.

[0008] Step 2: Establish a cylindrical coordinate system for one ring of the conducting loop; in the cylindrical coordinate system, use the differential form of Maxwell's equations as the electromagnetic field model; under steady voltage, transform Maxwell's equations into a quasi-static form, and based on the characteristic that the electric field is the potential gradient, obtain the divergence of the electric field and the curl of the magnetic field; solve for the divergence of the electric field and the curl of the magnetic field using the parameters from Step 1 to obtain the electric field and magnetic field of the conducting loop.

[0009] Establish a cylindrical coordinate system for one ring of the conductive ring, with the origin at the center of the bottom surface of the conductive ring. The z-axis is along the axis of the slip ring, r represents the radial distance of the point (i.e., the distance to the z-axis), and θ represents the rotation angle around the z-axis, describing the point's position in the ring direction. The coordinate point is represented as P:(r,θ,z). In the cylindrical coordinate system, Maxwell's equations in differential form are used as the mathematical model of the electromagnetic field.

[0010]

[0011] Where: H is the magnetic field strength; J is the current density; D is the electric displacement vector; E is the electric field strength; B m ρ is the magnetic induction intensity generated by the conductive ring; ρ is the charge density; t is the independent variable time.

[0012] Under steady voltage, Maxwell's equations simplify to a quasi-static form, where the electric and magnetic fields are independent, and the divergence of the electric field and the curl of the magnetic field are respectively:

[0013]

[0014] Where E r and E z ε is the component of the electric field intensity in cylindrical coordinates; ε is the dielectric constant; and E is the electric potential. The gradient of is then:

[0015]

[0016] Since the electric potential is axially symmetric, then Then there is

[0017]

[0018] Solving equation (5) yields the electric potential. The electric field E can be further obtained through equation (4);

[0019] The current density distribution J is obtained by solving equation (6):

[0020] J=σE (6)

[0021] Under steady-state conditions, Ampere's law is:

[0022]

[0023] Where σ is the electrical conductivity; μ0 is the free magnetic permeability; integrating equation (7) yields the magnetic field B. m .

[0024] Step 3: Perform force analysis on the wear debris in the body coordinate system. The forces include Earth's gravity, electric field force, Lorentz force, and, since the body coordinate system is a non-inertial frame, Coriolis force, centrifugal force, and Euler force. The magnetic flux density in the Lorentz force includes the Earth's magnetic field and the magnetic field generated by the conductive ring. Based on Newton's second law and the position vector transformation relationship between the body coordinate system and the inertial coordinate system, derive the wear debris dynamics equation in the body coordinate system. By solving the dynamics equation, obtain the trajectory of a single wear debris, thus realizing the prediction of conductive wear debris motion based on microgravity and multi-field coupling.

[0025] The method for force analysis of wear debris in the body coordinate system is as follows: when the wear debris does not contact the wall and moves in space, it is subject to the gravitational force G of the Earth and the electric force F of the charged wear debris in the electric field environment. e The Lorentz force F in the magnetic field environment generated by the electric field m .

[0026] The first-order gravitational force in the body coordinate system is expressed as:

[0027]

[0028] The superscript (c) indicates that the vector is located in the body coordinate system of the conductive ring; the superscript (i) indicates that the vector is located in the geocentric inertial frame; μ is the standard gravity parameter; R is the distance of the wear debris from the Earth's center of mass; r O This represents the position vector of the wear debris relative to the Earth's center of mass; the transformation matrix from the geocentric inertial coordinate system to the orbital coordinate system is denoted as... The transformation matrix for converting the orbital coordinate system to the body coordinate system is denoted as:

[0029] The electric force F experienced by charged grinding debris in an electric field e for:

[0030] F e =Eq (9)

[0031] The Lorentz force F experienced by charged grinding debris in a magnetic field m for

[0032] F m =qv q ×B (10)

[0033] Among them, v q B is the velocity of the grinding debris; B is the magnetic flux density; the magnetic flux density comes from two parts, one of which is the Earth's magnetic field, denoted as B. e The other part is the magnetic field generated by the current flowing through the conductive ring, denoted as B. m ;

[0034] B = B e +B m (11)

[0035] Accurate dynamic simulation analysis was performed using the 13th-order geomagnetic field model from the IGRF model, with geomagnetic field B... e In the geocentric inertial coordinate system, it is represented as:

[0036]

[0037] Where: r0 is the Earth's radius, r0 = 6371.2 km; θ B Latitude Coordinate latitude; φ B Longitude; These are Gaussian coefficients; For n B m B The first-order Schmitt function;

[0038] The forces and motions of the wear debris are coupled, and Newton's second law is applied in an inertial coordinate system:

[0039] G+F e +F m =ma (13) a is the acceleration of the grinding debris motion; the body coordinate system is a non-inertial coordinate system, and the position vector in the body coordinate system and the position vector in the inertial coordinate system have a transformation relationship:

[0040]

[0041] Where, r C Let F be the position vector of the wear debris relative to the center of the conductive ring; C represents the vector pointing from the Earth's center of mass to the center of the conductive ring; in the body coordinate system, the Coriolis force, centrifugal force, and Euler force also need to be considered; the Coriolis force, centrifugal force, and Euler force are written as F. i (c) :

[0042]

[0043] Where, ω (c) Let be the angular velocity of this system relative to the inertial frame; The velocity of the wear debris relative to the system; The location of the wear debris within this system;

[0044] angular velocity ω (c) It consists of two parts: the orbital angular velocity caused by the satellite's orbital motion. and attitude angular velocity caused by changes in satellite attitude Therefore, angular velocity is expressed as:

[0045]

[0046] orbital angular velocity The component in the orbital system is:

[0047]

[0048] In the formula

[0049]

[0050] Where 'a' is the semi-major axis of the orbit;

[0051] Attitude angular velocity Obtained from the rotation matrix

[0052]

[0053] Where vec(·) represents extracting the angular velocity component from the oblique symmetric matrix Ω, which satisfies:

[0054]

[0055] but

[0056]

[0057] The dynamic equations in the body coordinate system are:

[0058]

[0059] Beneficial effects:

[0060] 1. This invention discloses a method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling. It establishes a multi-physics coupling model and dynamic equations for conductive wear debris under the coupling environment of microgravity and complex electromagnetic fields. By constructing a dynamic model that includes the transformation relationship between the geocentric inertial frame, orbital frame, and body coordinate system, and combining Maxwell's equations to derive the distribution of electric and magnetic fields, it characterizes the motion characteristics of wear debris under the coupling of multiple forces such as microgravity, electric field force, Lorentz force, and inertial force, thereby improving the theoretical depth of the motion analysis of conductive wear debris.

[0061] 2. The present invention discloses a method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling. It clarifies that the electric field force is the dominant factor affecting the motion of wear debris, while the Lorentz force generated by the magnetic field of the conductive ring and the geomagnetic field can be ignored in short-term analysis. This simplifies the control equation of wear debris motion, which is helpful for carrying out wear debris motion simulation and analysis in engineering practice and reduces the complexity of wear debris motion simulation and analysis calculation.

[0062] 3. The present invention discloses a method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling. According to the on-orbit dynamic equation, the method obtains the law of wear debris migrating to the outer wall of the slip ring and forming an aggregate layer under the drive of electric field force. It clarifies the risk that the aggregate layer may cause circuit short circuit, partial discharge and wear failure of moving parts, which helps to optimize the structural design of the conductive ring of the spacecraft and further improves the long-term operational reliability of the conductive ring.

[0063] 4. The present invention discloses a method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling. It constructs a multi-physics coupling model under microgravity environment, establishes a method flow for predicting the motion of wear debris on spacecraft conductive rings, and realizes accurate prediction of the motion trajectory of conductive wear debris, effectively improving the accuracy and reliability of space mechanism wear risk prediction. Attached Figure Description

[0064] Figure 1 Schematic diagram of a disc slip ring model.

[0065] Figure 2 Schematic diagram of a conductive ring-cylindrical coordinate system.

[0066] Figure 3 Schematic diagram of a geocentric inertial coordinate system.

[0067] Figure 4 Schematic diagram of the orbital coordinate system.

[0068] Figure 5 Schematic diagram of the body coordinate system.

[0069] Figure 6 Schematic diagram of stress analysis on grinding debris.

[0070] Figure 7 Schematic diagram of the geometric model of a disc slip ring.

[0071] Figure 8 Potential distribution in the conductive ring.

[0072] Figure 9 Magnetic field distribution of the conductive ring.

[0073] Figure 10 Schematic diagram of the trajectory of a single grinding chip on a conductive ring.

[0074] Figure 11 Schematic diagram of the motion trajectory of the conductive ring in multiple models.

[0075] Figure 12 A flowchart of a method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling according to the present invention. Detailed Implementation

[0076] To better illustrate the purpose and advantages of the present invention, the specific embodiments and effects of the present invention will be further described in detail below with reference to examples and accompanying drawings.

[0077] This embodiment discloses a method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling. The specific implementation steps are as follows:

[0078] Step 1: Taking the conductive ring as the research object, conductive rings are divided into disc-type conductive rings and cylindrical conductive rings. The channels of a disc-type conductive ring are arranged parallel to each other on a disc-shaped plane, and the overall shape is a flat cylinder. The channels of a cylindrical conductive ring are arranged side-by-side on the outer surface of a cylinder, and the overall shape is a long, narrow cylinder. Based on the axial symmetry of the conductive ring, a 1 / 2 conductive ring is selected as the research object; the average mass m and charge q of the wear debris particles are determined; such as... Figure 7 As shown, the model structure is modeled at a 1:1 scale with the disc-type slip ring structure. The thickness of the conductive ring is determined to be 1.75 mm, the width to be 3.5 mm, and the mass of the charged particles is taken as the average mass of the grinding debris particles, 4.7 × 10⁻⁶. -11 kg, with an average charge number of 220e for charged particles. The slip ring operating voltage is 42V, the SADA bus transmission voltage in a geostationary satellite, with a negative terminal voltage of 0V. The slip ring operating current is set to 10A. A restitution coefficient e = 0.5 is applied on the axial planar boundary, and e = 0.6 is applied on the cylindrical surface.

[0079] Step 2: Establish a cylindrical coordinate system for one ring of the conductive ring, with the origin at the center of the bottom surface of the conductive ring. The z-axis is along the axis of the slip ring, r represents the radial distance of the point (i.e., the distance to the z-axis), and θ represents the rotation angle around the z-axis, describing the point's position in the ring direction. The coordinate point is represented as P:(r,θ,z). In the cylindrical coordinate system, Maxwell's equations in differential form are used as the mathematical model of the electromagnetic field.

[0080]

[0081] Where: H is the magnetic field strength; J is the current density; D is the electric displacement vector; E is the electric field strength; B m ρ is the magnetic induction intensity generated by the conductive ring; ρ is the charge density; t is the independent variable time.

[0082] Under steady voltage, Maxwell's equations simplify to a quasi-static form, where the electric and magnetic fields are independent, and the divergence of the electric field and the curl of the magnetic field are respectively:

[0083]

[0084]

[0085] Where E r and E z ε is the component of the electric field intensity in cylindrical coordinates; ε is the dielectric constant; and E is the electric potential. The gradient of is then:

[0086]

[0087] Since the electric potential is axially symmetric, then Then there is

[0088]

[0089] Given a conducting circular ring with a potential of 42V, solve the potential equation. Due to symmetry, the potential Φ(r,z) depends only on r and z, and therefore can be decoupled as a function of R(r) and Z(z):

[0090] Φ(r,z)=R(r)Z(z) (28)

[0091] The boundary conditions for the electric field problem can be described as follows:

[0092]

[0093] Electric potential can be expressed as the general solution Φ0 and the particular solution Φ * Superposition:

[0094] Φ=Φ0+Φ * (30)

[0095] The general solution is obtained by using the method of separation of variables.

[0096]

[0097] Where k n For eigenvalues; J n A is a Bessel function of the first kind; n The constants are obtained by substituting the expansion coefficients into the boundary conditions.

[0098]

[0099] The calculated potential distribution results are as follows: Figure 8 As shown, the electric field E is further obtained;

[0100] The current density distribution J is obtained by solving equation (6):

[0101] J=σE (33)

[0102] Under steady-state conditions, Ampere's law is:

[0103]

[0104] Where σ is the electrical conductivity; μ0 is the permeability of free space; the magnetic field can be obtained by integration.

[0105]

[0106] The magnetic field distribution results are as follows Figure 9 As shown.

[0107] Step 3: The method for force analysis of the wear debris in the body coordinate system is as follows: when the wear debris does not contact the wall and moves in space, it is subject to the gravitational force G of the Earth and the electric force F of the charged wear debris in the electric field environment. e The Lorentz force F in the magnetic field environment generated by the electric field m .

[0108] The expression for first-order gravity in body coordinates is:

[0109]

[0110] The superscript (c) indicates that the vector is located in the body coordinate system of the conductive ring; the superscript (i) indicates that the vector is located in the geocentric inertial frame; μ is the standard gravity parameter; R is the distance of the wear debris from the Earth's center of mass; r O This represents the position vector of the wear debris relative to the Earth's center of mass; the transformation matrix from the geocentric inertial coordinate system to the orbital coordinate system is denoted as... The transformation matrix for converting the orbital coordinate system to the body coordinate system is denoted as:

[0111] The electric force F experienced by charged grinding debris in an electric field e for:

[0112] F e =Eq (37)

[0113] The Lorentz force F experienced by charged grinding debris in a magnetic field m for

[0114] Fm =qv q ×B (38)

[0115] Among them, v q B is the velocity of the grinding debris; B is the magnetic flux density; the magnetic flux density comes from two parts, one of which is the Earth's magnetic field, denoted as B. e The other part is the magnetic field generated by the current flowing through the conductive ring, denoted as B. m ;

[0116] B = B e +B m (39)

[0117] Accurate dynamic simulation analysis was performed using the 13th-order geomagnetic field model from the IGRF model, with geomagnetic field B... e In the geocentric inertial coordinate system, it is represented as:

[0118]

[0119] Where: r0 is the Earth's radius, r0 = 6371.2 km; θ B Latitude Coordinate latitude; φ B Longitude; These are Gaussian coefficients; For n B m B The first-order Schmitt function;

[0120] The forces and motions of the wear debris are coupled, and Newton's second law is applied in an inertial coordinate system:

[0121] G+F e +F m =ma (41)a is the acceleration of the grinding debris motion; the body coordinate system is a non-inertial coordinate system, and the position vector in the body coordinate system and the position vector in the inertial coordinate system have a transformation relationship:

[0122]

[0123] Where, r C Let F be the position vector of the wear debris relative to the center of the conductive ring; C represents the vector pointing from the Earth's center of mass to the center of the conductive ring; in the body coordinate system, the Coriolis force, centrifugal force, and Euler force also need to be considered; the Coriolis force, centrifugal force, and Euler force are written as F. i (c) :

[0124]

[0125] Where, ω (c) Let be the angular velocity of this system relative to the inertial frame; The velocity of the wear debris relative to the system; The location of the wear debris within this system;

[0126] angular velocity ω (c) It consists of two parts: the orbital angular velocity caused by the satellite's orbital motion. and attitude angular velocity caused by changes in satellite attitude Therefore, angular velocity is expressed as:

[0127]

[0128] orbital angular velocity The component in the orbital system is:

[0129]

[0130] In the formula

[0131]

[0132] Where 'a' is the semi-major axis of the orbit;

[0133] Attitude angular velocity Obtained from the rotation matrix

[0134]

[0135] Where vec(·) represents extracting the angular velocity component from the oblique symmetric matrix Ω, which satisfies:

[0136]

[0137] but

[0138]

[0139] The dynamic equations in the body coordinate system are:

[0140]

[0141] The dynamic characteristics and motion laws of a single grinding debris are studied. The initial orbit of the spacecraft is (a,e,i,Ω,ω,ν)=(7000km,0,0,0,0,0), and the spacecraft attitude parameters are... The initial position of the grinding debris is at the center of the outermost ring, track number 12, of the conductive ring, with an initial velocity of v. x =0.001m / s, the trajectory of the grinding debris is obtained as follows Figure 7 As shown.

[0142] To record the collision process of metal particles, an RZ image is plotted, such as... Figure 10As shown in the figure, the right side represents the outer wall of the SADA housing. The magnitudes of the forces during the motion are shown in Table 1.

[0143] Table 1. Order of magnitude of forces during motion.

[0144]

[0145] During the motion, gravity provides the centripetal force, causing the spacecraft to orbit the Earth. This force is thus canceled out by centrifugal force and therefore does not affect the movement of the grinding debris. Among the remaining forces, the electric field force plays a dominant role in the motion of the metal particles. Its magnitude is 1–3 orders of magnitude larger than the Coriolis force and 7–10 orders of magnitude larger than the magnetic field force. The electric field force is the main driving force for the movement of the grinding debris. Unless extreme precision control scenarios or long-term cumulative effects are considered, the magnetic field force can be ignored.

[0146] Step 4: Investigate the motion patterns of multiple wear debris pieces. After the wear debris from the outermost slip ring is released with an initial velocity of 0.001-0.009 m / s, the trajectory of the wear debris is as follows: Figure 11 As shown, the debris continuously moves towards the outer wall under the drive of the electric field. The outer wall acts as a rigid constraint boundary, preventing further outward movement of the debris upon arrival. After multiple collisions, the momentum of the debris gradually decreases, causing it to accumulate and eventually gather on the outer wall. The momentum dissipation process from these multiple collisions leads to a debris aggregation effect near the outer wall. During long-term operation, this region forms an aggregate layer composed of metal particles, which may further trigger short circuits or partial discharges. Excessively high metal particle density in the aggregate layer may also accelerate the wear and failure of moving parts such as bearings, posing a potential threat to the long-term reliable operation of the spacecraft's conductive ring system.

[0147] The above detailed description further illustrates the purpose, technical solution, and beneficial effects of the invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for predicting the motion of conductive wear debris based on microgravity and multi-field coupling, characterized in that: Includes the following steps, Step 1: Taking the conductive ring as the object, based on the axial symmetry of the conductive ring, select a 1 / 2 conductive ring as the analysis object; determine the average mass m and charge q of the wear debris particles; Step 2: Establish a cylindrical coordinate system for one ring of the conducting loop; in the cylindrical coordinate system, use the differential form of Maxwell's equations as the electromagnetic field model; under steady voltage, transform Maxwell's equations into a quasi-static form, and based on the characteristic that the electric field is the potential gradient, obtain the divergence of the electric field and the curl of the magnetic field; solve for the divergence of the electric field and the curl of the magnetic field using the parameters from Step 1 to obtain the electric field and magnetic field of the conducting loop. Step 3: Perform force analysis on the wear debris in the body coordinate system. The forces include Earth's gravity, electric field force, Lorentz force, and, since the body coordinate system is a non-inertial frame, Coriolis force, centrifugal force, and Euler force. The magnetic flux density in the Lorentz force includes the Earth's magnetic field and the magnetic field generated by the conductive ring. Based on Newton's second law and the position vector transformation relationship between the body coordinate system and the inertial coordinate system, derive the wear debris dynamics equation in the body coordinate system. By solving the dynamics equation, obtain the trajectory of a single wear debris, thus realizing the prediction of conductive wear debris motion based on microgravity and multi-field coupling.

2. The method as described in claim 1, characterized in that: The cylindrical coordinate system described in step two is fixedly connected to the conductive ring body. The origin is the center point of the bottom surface of the conductive ring, the z-axis is along the axis of the slip ring, r represents the distance of the point in the radial direction, that is, the distance to the z-axis, and θ represents the rotation angle variable around the z-axis, describing the position of the point in the circumferential direction; the coordinate point is represented as P:(r,θ,z).

3. The method as described in claim 2, characterized in that: The electromagnetic field mathematical model described in step two, using the differential form of Maxwell's equations to describe any point, is as follows: Where: H is the magnetic field strength; J is the current density; D is the electric displacement vector; E is the electric field strength; B m ρ is the magnetic induction intensity generated by the conductive ring; ρ is the charge density; t is the independent variable time.

4. The method as described in claim 3, characterized in that: Step two yields the divergence of the electric field and the curl of the magnetic field. Under steady voltage, Maxwell's equations simplify to a quasi-static form, where the electric and magnetic fields are independent. The divergence of the electric field and the curl of the magnetic field are respectively: Where E r and E z ε is the component of the electric field intensity in cylindrical coordinates; ε is the dielectric constant; and E is the electric potential. The gradient of is then: Since the electric potential is axially symmetric, then Then there is 。 5. The method as described in claim 4, characterized in that: The method for obtaining the electric and magnetic fields of the conductive ring described in step two is as follows: Solving equation (5) yields the electric potential. The electric field E can be further obtained through equation (4); The current density distribution J is obtained by solving equation (6): J=σE (6) Under steady-state conditions, Ampere's law is: Where σ is the electrical conductivity; μ0 is the free magnetic permeability; integrating equation (7) yields the magnetic field B. m .

6. The method as described in claim 5, characterized in that: Step three describes the method for force analysis of the wear debris in the body coordinate system. When the wear debris does not contact the wall and moves in space, it is subject to the gravitational force G of the Earth and the electric force F experienced by the charged wear debris in the electric field environment. e The Lorentz force F in the magnetic field environment generated by the electric field m .

7. The method as described in claim 6, characterized in that: Based on Newton's second law and combining the position vector transformation relationship between the body coordinate system and the inertial coordinate system, the method for obtaining the grinding debris dynamics equation in the body coordinate system is as follows: The first-order gravitational force in the body coordinate system is expressed as: The superscript (c) indicates that the vector is located in the body coordinate system of the conductive ring; the superscript (i) indicates that the vector is located in the geocentric inertial frame; μ is the standard gravity parameter; R is the distance of the wear debris from the Earth's center of mass; r O This represents the position vector of the wear debris relative to the Earth's center of mass; the transformation matrix from the geocentric inertial coordinate system to the orbital coordinate system is denoted as... The transformation matrix for converting the orbital coordinate system to the body coordinate system is denoted as: The electric force F experienced by charged grinding debris in an electric field e for: F e =Eq (9) The Lorentz force F experienced by charged grinding debris in a magnetic field m for: F m =qv q ×B (10) where, v q B is the velocity of the grinding debris; B is the magnetic flux density; the magnetic flux density comes from two parts, one of which is the Earth's magnetic field, denoted as B. e The other part is the magnetic field generated by the current flowing through the conductive ring, denoted as B. m ; B=B e +B m (11) Accurate dynamic simulation analysis was performed using the 13th-order geomagnetic field model from the IGRF model, with geomagnetic field B... e In the geocentric inertial coordinate system, it is represented as: Where: r0 is the Earth's radius, r0 = 6371.2 km; θ B Latitude Coordinate latitude; φ B Longitude; These are Gaussian coefficients; For n B m B The first-order Schmitt function; The forces and motions of the wear debris are coupled, and Newton's second law is applied in an inertial coordinate system: G+F e +F m =in (13) 'a' represents the acceleration of the grinding debris; the body coordinate system is a non-inertial coordinate system, and the position vector in the body coordinate system and the position vector in the inertial coordinate system have a transformation relationship: Where, r C Let F be the position vector of the wear debris relative to the center of the conductive ring; C represents the vector pointing from the Earth's center of mass to the center of the conductive ring; in the body coordinate system, the Coriolis force, centrifugal force, and Euler force also need to be considered; the Coriolis force, centrifugal force, and Euler force are written as F. i (c) : Where, ω (c) Let be the angular velocity of this system relative to the inertial frame; The velocity of the wear debris relative to the system; The location of the wear debris within this system; angular velocity ω (c) It consists of two parts: the orbital angular velocity caused by the satellite's orbital motion. and attitude angular velocity caused by changes in satellite attitude Angular velocity is expressed as: orbital angular velocity The component in the orbital system is: In the formula Where 'a' is the semi-major axis of the orbit; Attitude angular velocity Obtained from the rotation matrix Where vec(·) represents extracting the angular velocity component from the oblique symmetric matrix Ω, which satisfies: but The dynamic equations in the body coordinate system are: 。 8. The method as described in claim 7, characterized in that: The conductive rings mentioned in step one are divided into disc-type conductive rings and column-type conductive rings. The channels of the disc-type conductive ring are arranged in parallel on a disc-shaped plane, and the overall shape is a flat cylinder. The channels of the column-type conductive ring are arranged side by side on the outer surface of a cylinder, and the overall shape is a long cylinder.

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