Flywheel magnetic unloading method, device and storage medium for satellite

Abstract

The present application discloses a flywheel magnetic unloading method, device and storage medium for satellites. It relates to the field of satellite attitude control technology. The method includes: determining the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum; determining the unloading magnetic moment for flywheel unloading according to the angular momentum difference and the magnetic field strength of the earth's magnetic field; determining the mapping relationship between the magnetic moment mapping of the magnetic moment and the magnetic moment component corresponding to the unloading magnetic moment according to the angle between the magnetic moment magnetic moment of multiple magnetic torquers arranged on the satellite and the unloading magnetic moment; and optimizing the magnetic moment magnetic moment of multiple magnetic torquers according to the mapping relationship and the energy consumption characteristics of multiple magnetic torquers. The technical problem of minimizing the energy consumption of magnetic torquers during flywheel magnetic unloading is solved.

Description

Technical Field

[0001] The present application relates to the technical field of satellite attitude control, and in particular to a flywheel magnetic unloading method, device and storage medium for a satellite. Background Art

[0002] The flywheel magnetic unloading system is an important component of the satellite attitude control system, which is mainly used to manage the momentum accumulated in the flywheel. During the operation of the satellite, the flywheel generates torque by changing its rotation speed to adjust the satellite's attitude. However, as the flywheel continues to work, the momentum accumulated inside it will gradually increase, and when it reaches a certain level, it may affect the stability and control accuracy of the satellite. In order to prevent this from happening, the flywheel magnetic unloading system is designed to periodically "unload" excess momentum from the flywheel. This process is achieved through magnetic torquers. Magnetic torquers are deployed on the three axes of the satellite passing through the center of mass. They can generate torque that interacts with the Earth's magnetic field, thereby transferring the excess momentum in the flywheel to the Earth's magnetic field without consuming propellant, thereby achieving momentum "unloading".

[0003] With the widespread use of low-orbit satellites, the size of satellites has been continuously reduced, and higher requirements have been put forward for the optimization of energy consumption. Therefore, it has become a technical problem that needs to be solved urgently to reduce the energy consumption of each magnetic torquer as much as possible during the flywheel magnetic unloading process.

[0004] The publication number is CN109625329A, and the name is a method for autonomous unloading of flywheel angular momentum based on discrete jets, which includes the following steps: calculating the angular momentum of the satellite body; determining the unloading threshold of the flywheel angular momentum; calculating the duration of each jet of the unloading thruster; calculating the interval time between each unloading jet of the thruster; and calculating the number of unloading jets of the thruster. The satellite angular momentum is calculated according to the rotation speed of the flywheel, and the unloading thruster, the time width of the thruster jet, the jet interval time, and the number of jets are selected according to the installation layout of the thruster and the requirements of the satellite attitude control accuracy and stability. The present invention is based on the use of the autonomous angular momentum unloading technology of the thruster discrete "point jet", which can ensure that the angular momentum unloading is autonomously realized under the premise of meeting the attitude control accuracy, thereby improving the satellite's autonomous operation capability in orbit.

[0005] The publication number is CN109649691A, and the name is a biased momentum satellite single flywheel and magnetic joint control method and system. The method includes: calculating the magnetic unloading instruction magnetic moment according to the pitch attitude angle; calculating the magnetic precession instruction magnetic moment according to the roll attitude angle, the yaw attitude angle, the roll attitude angular velocity and the yaw attitude angular velocity; superimposing the magnetic unloading instruction magnetic moment with the magnetic precession instruction magnetic moment to obtain the total instruction magnetic moment.

[0006] With respect to the above-mentioned technical problem of how to reduce the energy consumption of the magnetic torquer as much as possible during the process of flywheel magnetic unloading, no effective solution has been proposed yet. Summary of the invention

[0007] The embodiments of the present application provide a flywheel magnetic unloading method, device and storage medium for a satellite, so as to at least solve the technical problem of minimizing the energy consumption of the magnetic torquer during the flywheel magnetic unloading process.

[0008] According to one aspect of an embodiment of the present application, a flywheel magnetic unloading method for a satellite is provided, comprising: determining the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum; determining the unloading magnetic moment for flywheel unloading based on the angular momentum difference and the magnetic field strength of the earth's magnetic field; determining a mapping relationship between the magnetic moment mapping of the magnetic moment and the magnetic moment component corresponding to the unloading magnetic moment based on the angle between the magnetic moment magnetic moment of multiple magnetic torquers arranged on the satellite and the unloading magnetic moment; and optimizing the magnetic moment magnetic moment of multiple magnetic torquers based on the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers.

[0009] According to another aspect of an embodiment of the present application, a storage medium is further provided, the storage medium including a stored program, wherein the above-described method is executed by a processor when the program is running.

[0010] According to another aspect of an embodiment of the present application, a flywheel magnetic unloading device for a satellite is also provided, including: an angular momentum difference determination module, used to determine the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum; an unloading magnetic moment determination module, used to determine the unloading magnetic moment for flywheel unloading based on the angular momentum difference and the magnetic field strength of the earth's magnetic field; a mapping determination module, used to determine the mapping relationship between the magnetic moment mapping and the magnetic moment component corresponding to the unloading magnetic moment based on the angle between the magnetic moment magnetic moment of multiple magnetic torquers arranged on the satellite and the unloading magnetic moment; and an optimization module, used to optimize the magnetic moment magnetic moment of multiple magnetic torquers based on the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers.

[0011] According to another aspect of an embodiment of the present application, a flywheel magnetic unloading device for a satellite is also provided, comprising: a processor; and a memory connected to the processor, for providing the processor with instructions for processing the following processing steps: determining the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum; determining the unloading magnetic moment for flywheel unloading based on the angular momentum difference and the magnetic field strength of the earth's magnetic field; determining a mapping relationship between the magnetic moment mapping of the magnetic moment to the magnetic moment component corresponding to the unloading magnetic moment based on the angle between the magnetic moment magnetic moment of multiple magnetic torquers arranged on the satellite and the unloading magnetic moment; and optimizing the magnetic moment magnetic moment of multiple magnetic torquers based on the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers.

[0012] In an embodiment of the present application, the unloading magnetic moment for flywheel unloading is determined based on the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum and the magnetic field strength of the earth's magnetic field. Then, based on the angle between the magnetic moment of the magnetic torque of multiple magnetic torquers arranged on the satellite and the unloading magnetic moment, the mapping relationship between the magnetic moment of the magnetic torque and the magnetic moment component corresponding to the unloading magnetic moment is determined, and the magnetic moment of the magnetic torque of multiple magnetic torquers is further optimized based on the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers. In this way, the magnetic moment of each magnetic torquer can be optimized through an optimization algorithm, so that while realizing the flywheel unloading process, the overall energy consumption of multiple magnetic torquers is controlled to the lowest level, and the energy consumption of each magnetic torquer is reduced as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0014] Figure 1 is a schematic diagram of the hardware architecture of a satellite system for implementing the method described in Example 1 of the present application;

[0015] Figure 2 is a system schematic diagram of attitude control of the satellite system according to Example 1 of the present application;

[0016] Figure 3 is a schematic flow chart of a flywheel magnetic unloading method for a satellite according to Embodiment 1 of the present application;

[0017] Figure 4 It is a schematic diagram of a process for optimizing the magnitude of the magnetic moment according to the constraint conditions and the objective function described in Example 1 of the present application;

[0018] Figure 5 is a schematic diagram of a flywheel magnetic unloading device for a satellite according to Embodiment 2 of the present application; and

[0019] Figure 6 This is a schematic diagram of a flywheel magnetic unloading device for a satellite according to Example 3 of the present application. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the technical solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only embodiments of a part of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application.

[0021] 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 sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. 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 comprising 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.

[0022] Example 1

[0023] According to this embodiment, a method embodiment of a flywheel magnetic unloading method for a satellite is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0024] Figure 1 The schematic diagram further shows the hardware architecture of the satellite system 10 according to this embodiment. Figure 1 As shown, the satellite system 10 includes an integrated electronic system, which includes: a processor, a memory, a bus management module and a communication interface. The memory is connected to the processor, so that the processor can access the memory, read the program instructions stored in the memory, read data from the memory or write data to the memory. The bus management module is connected to the processor and is also connected to a bus such as a CAN bus. Therefore, the processor can communicate with the satellite-borne peripherals connected to the bus through the bus managed by the bus management module. In addition, the processor is also connected to communication devices such as cameras, star sensors, measurement and control transponders, and data transmission equipment via the communication interface. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the above electronic device. Figure 1More or fewer components as shown, or with Figure 1 Different configurations shown.

[0025] exist Figure 1 On the basis of Figure 2 A schematic diagram of a system for attitude control of the satellite system 10 is further shown. Figure 2 As shown, the system includes a processor 110, a first magnetic torquer 121, a second magnetic torquer 122, a third magnetic torquer 123 and a flywheel 130. The processor 110 may be, for example, Figure 1 The magnetic torquers 121-123 and the flywheel 130 can communicate with the processor 110 via a CAN bus, for example.

[0026] Under the above operating environment, according to the first aspect of this embodiment, a flywheel magnetic unloading method for a satellite is provided, the method comprising: Figure 2 The processor 110 shown in FIG. Figure 3 A schematic diagram showing the process of the method is shown in FIG. Figure 3 As shown, the method includes:

[0027] S302: Determine the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum;

[0028] S304: determining an unloading magnetic moment for unloading the flywheel according to the angular momentum difference and the magnetic field strength of the earth's magnetic field;

[0029] S306: determining a mapping relationship between the magnetic moment and the magnetic moment component corresponding to the unloading magnetic moment according to the angle between the magnetic moment and the unloading magnetic moment of a plurality of magnetic torquers disposed on the satellite; and

[0030] S308: Optimizing the magnetic torques of the multiple magnetic torquers according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers.

[0031] Specifically, when the flywheel 130 needs to be unloaded, the processor 110 receives the actual current angular momentum of the flywheel 130 measured by the sensor, and the processor 110 can obtain the target angular momentum of the flywheel 130 from the memory.

[0032] When the processor 110 determines that the actual angular momentum of the current flywheel 130 is greater than the target angular momentum, the angular momentum difference between the actual angular momentum and the target angular momentum is determined. (S302).

[0033] Then, the processor 110 further determines the magnetic field strength of the current earth's magnetic field based on the data measured by the sensor. And, the processor 110 calculates the angular momentum difference and magnetic field strength , according to the following formula, determine the unloading magnetic moment used to unload the flywheel (S304):

[0034] (1).

[0035] in, α To control the gain.

[0036] Further, the processor 110 determines the magnetic torque generated by the first magnetic torque device 121, the second magnetic torque device 122 and the third magnetic torque device 123 and the unloading magnetic torque For example, the first magnetic torque generated by the first magnetic torquer 121 is Unloading moment The angle between ψ 1; The second magnetic torque generated by the second magnetic torquer 122 Unloading moment The angle between ψ 2; and the third magnetic torque generated by the third magnetic torque device 123 Unloading moment The angle between ψ 3.

[0037] Thus, further, the processor 110 can determine the magnetic moment component corresponding to the unloading magnetic moment mapped from the magnetic moment according to the following formula: The mapping relationship between (S306):

[0038] (2);

[0039] (3);

[0040] (4).

[0041] in is the magnetic moment component The size of is the magnetic moment size.

[0042] In addition, the energy consumption characteristics of the magnetic torquers 121-123 can be described, for example, according to the following formulas (5)-(7):

[0043] (5);

[0044] (6);

[0045] (7).

[0046] in, P 1~ P 3 are the powers of the magnetic torquers 121 to 123, m 1~ m 3 is the magnitude of the magnetic moment of each magnetic torquer 121-123, ρ is the resistivity of the coil wire of the magnetic torquer 121-123, μ e is the effective magnetic permeability of the magnetic bars of the magnetic torquers 121 to 123, N is the number of coil turns of the magnetic torquers 121 to 123, d is the diameter of the magnetic rods of the magnetic torquers 121 to 123, d w is the diameter of the coil wire of the magnetic torquer 121~123.

[0047] In this embodiment, the magnetic torquers 121-123 are of the same model, so the parameters related to the magnetic torquers are of the same value. When different models of magnetic torquers are used, the parameters of each magnetic torquer are also different.

[0048] Then, further, the processor 110 calculates the magnetic torque of each magnetic torquer 121-123 according to the mapping relationship described in the above formulas (2)-(4) and the energy consumption characteristics of each magnetic torquer 121-123 shown in formulas (5)-(7). Optimization is performed (S308). The specific optimization method will be described in detail below.

[0049] As described in the background technology, magnetic torquers are deployed on the three axes of the satellite passing through the center of mass. They can generate torque that interacts with the earth's magnetic field, thereby transferring the excess momentum in the flywheel to the earth's magnetic field without consuming propellant, thereby achieving momentum "unloading". However, with the widespread use of low-orbit satellites, the size of satellites continues to shrink, and higher requirements are also placed on the optimization of energy consumption. Therefore, if the energy consumption of each magnetic torquer is reduced as much as possible during the flywheel magnetic unloading process, it has become a technical problem that urgently needs to be solved.

[0050] In view of this, according to the technical solution of this embodiment, the unloading magnetic moment for flywheel unloading is determined according to the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum and the magnetic field strength of the earth's magnetic field. Then, according to the angle between the magnetic moment of the magnetic moment of the multiple magnetic torquers set on the satellite and the unloading magnetic moment, the mapping relationship between the magnetic moment of the magnetic moment and the magnetic moment component corresponding to the unloading magnetic moment is determined, and the magnetic moment of the multiple magnetic moments is further optimized according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers. In this way, the magnetic moment of each magnetic torquer can be optimized through an optimization algorithm, so that while realizing the flywheel unloading process, the overall energy consumption of the multiple magnetic torquers is controlled to the lowest level, and the energy consumption of each magnetic torquer is reduced as much as possible.

[0051] Optionally, the operation of optimizing the magnetic torque of multiple magnetic torquers according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers includes: determining the constraints on the magnetic torque according to the mapping relationship and the unloading magnetic moment; determining the optimization objective function according to the energy consumption characteristics of the multiple magnetic torquers; and optimizing the size of the magnetic torque according to the constraints and the objective function.

[0052] Specifically, the processor 110 may determine the following constraints:

[0053] m 1, m 2, m 3≤ m r (8), where m r is the rated magnetic moment of the magnetic torquers 121-123;

[0054] ,Right now, (9), where m u To unload the magnetic moment size.

[0055] In addition, the processor 110 determines the total power consumption of the three magnetic torquers 121-123 as the objective function F :

[0056] (10).

[0057] Then, the processor 110 determines the constraints according to formulas (8) to (9) and the objective function according to formula (10): F , and the magnitude of the magnetic moment of the multiple magnetic moments is determined according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers. m 1~ m3. The optimization result is to make the objective function F The value of is the smallest.

[0058] Therefore, by optimizing in this way, the total power consumption of the three magnetic torquers can be minimized while satisfying the constraints (that is, ensuring that the magnetic torque of the three magnetic torquers can unload the flywheel).

[0059] Optionally, the operation of optimizing the size of the magnetic moment according to the constraints and the objective function includes: randomly generating multiple solution vectors corresponding to the size of the magnetic moment according to the constraints; substituting the multiple solution vectors into the objective function respectively, and determining the function values ​​corresponding to each solution vector; determining the minimum value corresponding to the objective function according to the function values ​​corresponding to each solution vector; and iterating the multiple solution vectors according to the iterative algorithm corresponding to the minimum value of the objective function until the multiple solution vectors converge.

[0060] Specifically, Figure 4 The figure shows a schematic diagram of the process of optimizing the magnitude of the magnetic moment according to the constraint conditions and the objective function. Figure 4 As shown, the processor 110 optimizes the magnitude of the magnetic moment based on the particle swarm optimization algorithm by performing the following operations:

[0061] S402: According to the constraints shown in formulas (8) and (9), randomly generate n Solution vector M j , where 1≤ j ≤ n . Among them, the solution vector M j It is expressed in the following way:

[0062] M j =[ m 1,j , m 2,j , m 3,j ] T (11), where m 1,j Indicates j The magnitude of the magnetic moment of the first magnetic torquer in the solution vector; m 2,j Indicates j The magnitude of the magnetic moment of the second magnetic torquer in the solution vector; and m 3,j Indicates j The magnitude of the magnetic torque of the third magnetic torquer in the solution vector.

[0063] S404: Based on the randomly generated solution vectors M j =[ m 1,j , m 2,j , m 3,j ] T , perform initialization operations, including:

[0064] 1) For each solution vector M j The corresponding historical optimal solution Mbest j To initialize:

[0065] Mbest j = M j (12);

[0066] 2) For all historical optimal solutions Mbest j The optimal solution in Mbest To initialize:

[0067] Each solution vector M j =[ m 1,j , m 2,j , m 3,j ] T Substitute them into the objective function shown in formula (10) to obtain the solution vectors M j The corresponding objective function value F j :

[0068] (13),

[0069] According to each solution vector M j The corresponding objective function value F j , for each solution vector M j The corresponding optimal function value Fbest j And the optimal function value of all solution vectors Fbest To initialize:

[0070] Fbest j = Fj (14);

[0071] (15),

[0072] will be the optimal function value Fbest The corresponding solution vector is the optimal solution of all history Mbest j The optimal solution in Mbest ;as well as

[0073] 3) For each solution vector M j Corresponding speed coefficient V j Initialize, where V j =[ v 1,j , v 2,j , v 3,j ] T , v 1,j ~ v 3,j Respectively represent the magnitude of the magnetic moment and the magnetic moment m 1,j ~ m 3,j The corresponding speed factor.

[0074] S406: Based on each solution vector M j The corresponding historical optimal solution Mbest j And all historical optimal solutions Mbest j The optimal solution in Mbest , for each solution vector M j and the speed factor V j To update:

[0075] Specifically, the solution vectors are calculated according to the following formula: M j and the corresponding speed coefficient V j To update:

[0076] (16); and

[0077] M j k+1 = M j k+ V j k+1 (17).

[0078] in M j k and V j k Respectively expressed in k The solution vector determined by the iteration M j and the speed factor V j ; M j k+1 and V j k+1 Respectively expressed in k +1 solution vector determined by iteration M j and the speed factor V j . w is the inertia factor and can take non-negative values. c 1 and c 2 are learning factors, which are used to adjust the convergence speed of the algorithm. r 1 and r 2 is a random number between 0 and 1.

[0079] S408: Based on the updated solution vector M j , for each solution vector M j The corresponding optimal function value Fbest j And the optimal function value of all solution vectors Fbest To update:

[0080] First, the updated solution vectors M j k+1 Substitute into the objective function described in formula (10) to obtain the updated values ​​of each objective function F j k+1 Then, according to the updated objective function value F j k+1 , for each solution vector M j The corresponding optimal function value Fbest j And the optimal function value of all solution vectors Fbest To update:

[0081] Fbest j k+1 = min ( Fbest j k , F j k+1 );as well as

[0082] Fbest k+1 = min ( Fbest j k+1 ), j =1~ n .

[0083] S410: Determine whether a condition for iteration termination is met, where the iteration termination condition may be any one of the following conditions:

[0084] 1) Number of iterations k Reaching a preset threshold;

[0085] 2) After a predetermined number of consecutive iterations, the optimal function value of all solution vectors Fbest No longer changes.

[0086] If the conditions for iteration termination are met, the updated optimal function value Fbest The corresponding solution vector Mbest , as the optimized magnetic moment (S412). Otherwise, return to step S406 to perform a new round of iteration.

[0087] Therefore, the present invention uses the above solution to optimize the magnetic moment of each magnetic torquer 121-123 by setting an objective function for reducing energy consumption during the process of unloading the flywheel 130 using the magnetic torquers 121-123, thereby minimizing the energy consumption during the unloading process of the flywheel.

[0088] In addition, reference Figure 1 As shown, according to the second aspect of this embodiment, a storage medium is provided, wherein the storage medium includes a stored program, wherein when the program is run, a processor executes any one of the above methods.

[0089] Thus, according to this embodiment, the unloading magnetic moment for flywheel unloading is determined according to the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum and the magnetic field strength of the earth's magnetic field. Then, according to the angle between the magnetic moment of the magnetic moment of the multiple magnetic torquers set on the satellite and the unloading magnetic moment, the mapping relationship between the magnetic moment of the magnetic moment and the magnetic moment component corresponding to the unloading magnetic moment is determined, and the magnetic moment of the multiple magnetic moments is further optimized according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers. Thus, in this way, the magnetic moment of each magnetic torquer can be optimized through the optimization algorithm, so that while realizing the flywheel unloading process, the overall energy consumption of the multiple magnetic torquers is controlled to the lowest level, and the energy consumption of each magnetic torquer is reduced as much as possible.

[0090] It should be noted that, for the above-mentioned method embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the described action sequence, because according to the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

[0091] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0092] Example 2

[0093] Figure 5 A flywheel magnetic unloading device 500 for a satellite according to the first aspect of this embodiment is shown, and the device 500 corresponds to the method according to the first aspect of embodiment 1. Figure 5As shown, the device 500 includes: an angular momentum difference determination module 510, which is used to determine the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum; an unloading magnetic moment determination module 520, which is used to determine the unloading magnetic moment for unloading the flywheel according to the angular momentum difference and the magnetic field strength of the earth's magnetic field; a mapping determination module 530, which is used to determine the mapping relationship between the magnetic moment mapping and the magnetic moment component corresponding to the unloading magnetic moment according to the angle between the magnetic moment magnetic moment of multiple magnetic torquers set on the satellite and the unloading magnetic moment; and an optimization module 540, which is used to optimize the magnetic moment magnetic moment of multiple magnetic torquers according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers.

[0094] Optionally, the optimization module 540 includes: a constraint determination submodule, which is used to determine the constraint conditions for the magnetic torque based on the mapping relationship and the unloading magnetic moment; an objective function determination submodule, which is used to determine the objective function for optimization based on the energy consumption characteristics of multiple magnetic torquers; and an optimization submodule, which is used to optimize the size of the magnetic torque based on the constraint conditions and the objective function.

[0095] Optionally, the optimization submodule includes: a solution vector generation unit, which is used to randomly generate multiple solution vectors corresponding to the size of the magnetic moment according to the constraint conditions; an objective function calculation unit, which is used to substitute the multiple solution vectors into the objective function respectively, and determine the objective function value corresponding to each solution vector; an extreme value determination unit, which is used to determine the minimum value corresponding to the objective function according to the objective function value corresponding to each solution vector; and an iteration unit, which is used to iterate the multiple solution vectors according to an iterative algorithm related to the minimum value of the objective function, and when the conditions for iteration termination are met, determine the size of the magnetic moment according to the optimal solution of the multiple solution vectors.

[0096] Optionally, the plurality of magnetic torquers are three magnetic torquers respectively arranged on three axes of the satellite, and the constraint condition is:

[0097] m 1, m 2, m 3≤ m r ;as well as

[0098] .

[0099] in, m 1. m 2 and m 3 are the magnitudes of the magnetic moments of the three magnetic torquers during the flywheel unloading process; m r is the rated magnetic moment of the three magnetic torquers; m u is an unloading magnetic moment for unloading the flywheel; and ψ i For the i The magnetic torque generated by the magnetic torquer m i Unloading moment m u The angle between.

[0100] Optionally, the objective function is:

[0101] .

[0102] in, ρ is the resistivity of the coil wire of the magnetic torquer, μ e is the effective magnetic permeability of the magnetic bar of the magnetic torquer, N is the number of coil turns of the magnetic torquer, d is the diameter of the magnetic bar of the magnetic torquer, d w is the diameter of the coil wire of the magnetic torquer.

[0103] Optionally, the iteration unit includes an iteration subunit, configured to perform an iterative operation on the plurality of solution vectors according to the following formula:

[0104] ;as well as

[0105] M j k+1 = M j k + V j k+1 .

[0106] in M j k and V j k Respectively expressed in k The solution vector determined by the iteration M j and the speed factor V j ; M j k+1 and V j k+1 Respectively expressed in k +1 solution vector determined by iteration M j and the speed factor V j ;w is the inertia factor, which takes a non-negative value; c 1 and c 2 are learning factors, which are used to adjust the convergence speed of the algorithm; and r 1 and r 2 is a random number between 0 and 1.

[0107] Optionally, the conditions for terminating the iteration include: the number of iterations reaches a preset threshold; or after a predetermined number of consecutive iterations, the optimal function values ​​corresponding to the multiple solution vectors no longer change.

[0108] In an embodiment of the present application, the unloading magnetic moment for flywheel unloading is determined based on the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum and the magnetic field strength of the earth's magnetic field. Then, based on the angle between the magnetic moment of the magnetic torque of multiple magnetic torquers arranged on the satellite and the unloading magnetic moment, the mapping relationship between the magnetic moment of the magnetic torque and the magnetic moment component corresponding to the unloading magnetic moment is determined, and the magnetic moment of the magnetic torque of multiple magnetic torquers is further optimized based on the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers. In this way, the magnetic moment of each magnetic torquer can be optimized through an optimization algorithm, so that while realizing the flywheel unloading process, the overall energy consumption of multiple magnetic torquers is controlled to the lowest level, and the energy consumption of each magnetic torquer is reduced as much as possible.

[0109] Example 3

[0110] Figure 6 A flywheel magnetic unloading device 600 for a satellite according to the first aspect of this embodiment is shown, and the device 600 corresponds to the method according to the first aspect of embodiment 1. Figure 6 As shown, the device 600 includes: a processor 610; and a memory 620, which is connected to the processor 610 and is used to provide the processor 610 with instructions for processing the following processing steps: determining the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum; determining the unloading magnetic moment for unloading the flywheel based on the angular momentum difference and the magnetic field strength of the earth's magnetic field; determining the mapping relationship between the magnetic moment mapping and the magnetic moment component corresponding to the unloading magnetic moment based on the angle between the magnetic moment magnetic moment of multiple magnetic torquers set on the satellite; and optimizing the magnetic moment magnetic moment of multiple magnetic torquers based on the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers.

[0111] Optionally, the operation of optimizing the magnetic torque of multiple magnetic torquers according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers includes: determining the constraints on the magnetic torque according to the mapping relationship and the unloading magnetic moment; determining the objective function for optimization according to the energy consumption characteristics of the multiple magnetic torquers; and optimizing the size of the magnetic torque according to the constraints and the objective function.

[0112] Optionally, the operation of optimizing the size of the magnetic moment according to the constraints and the objective function includes: randomly generating multiple solution vectors corresponding to the size of the magnetic moment according to the constraints; substituting the multiple solution vectors into the objective function respectively, and determining the objective function values ​​corresponding to each solution vector; determining the minimum value corresponding to the objective function according to the objective function values ​​corresponding to each solution vector; and iterating the multiple solution vectors according to an iterative algorithm related to the minimum value of the objective function, and when the conditions for iteration termination are met, determining the size of the magnetic moment according to the optimal solution of the multiple solution vectors.

[0113] Optionally, the plurality of magnetic torquers are three magnetic torquers respectively arranged on three axes of the satellite, and the constraint condition is:

[0114] m 1, m 2, m 3≤ m r ;as well as

[0115] .

[0116] in, m 1. m 2 and m 3 are the magnitudes of the magnetic moments of the three magnetic torquers during the flywheel unloading process; m r is the rated magnetic moment of the three magnetic torquers; m u is an unloading magnetic moment for unloading the flywheel; and ψ i For the i The magnetic torque generated by the magnetic torquer m i Unloading moment m u The angle between.

[0117] Optionally, the objective function is:

[0118] .

[0119] in, ρ is the resistivity of the coil wire of the magnetic torquer, μ e is the effective magnetic permeability of the magnetic bar of the magnetic torquer, N is the number of coil turns of the magnetic torquer, d is the diameter of the magnetic bar of the magnetic torquer, d w is the diameter of the coil wire of the magnetic torquer.

[0120] Optionally, performing an iterative operation on the multiple solution vectors according to an iterative algorithm corresponding to the minimum value of the objective function includes performing an iterative operation on the multiple solution vectors according to the following formula:

[0121] ;as well as

[0122] M j k+1 = M j k + V j k+1 .

[0123] in M j k and V j k Respectively expressed in k The solution vector determined by the iteration M j and the speed factor V j ; M j k+1 and V j k+1 Respectively expressed in k +1 solution vector determined by iteration M j and the speed factor V j ; w is the inertia factor, which takes a non-negative value; c 1 and c 2 are learning factors, which are used to adjust the convergence speed of the algorithm; and r 1 and r 2 is a random number between 0 and 1.

[0124] Optionally, the conditions for terminating the iteration include: the number of iterations reaches a preset threshold; or after a predetermined number of consecutive iterations, the optimal function values ​​corresponding to the multiple solution vectors no longer change.

[0125] In an embodiment of the present application, the unloading magnetic moment for flywheel unloading is determined based on the angular momentum difference between the actual angular momentum of the flywheel and the target angular momentum and the magnetic field strength of the earth's magnetic field. Then, based on the angle between the magnetic moment of the magnetic torque of multiple magnetic torquers arranged on the satellite and the unloading magnetic moment, the mapping relationship between the magnetic moment of the magnetic torque and the magnetic moment component corresponding to the unloading magnetic moment is determined, and the magnetic moment of the magnetic torque of multiple magnetic torquers is further optimized based on the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers. In this way, the magnetic moment of each magnetic torquer can be optimized through an optimization algorithm, so that while realizing the flywheel unloading process, the overall energy consumption of multiple magnetic torquers is controlled to the lowest level, and the energy consumption of each magnetic torquer is reduced as much as possible.

[0126] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0127] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0128] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0129] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0130] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0131] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk, etc. Various media that can store program codes.

[0132] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A flywheel magnetic unloading method for a satellite, characterized in that: include: determining an angular momentum difference between an actual angular momentum of the flywheel and a target angular momentum; determining an unloading magnetic moment for unloading the flywheel according to the angular momentum difference and the magnetic field strength of the earth's magnetic field; Determine a mapping relationship between the magnetic moment of a plurality of magnetic torquers disposed on the satellite and the magnetic moment of the unloading magnetic moment and a magnetic moment component corresponding to the magnetic moment of the unloading magnetic moment; as well as The magnetic torques of the multiple magnetic torquers are optimized according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers, wherein The operation of optimizing the magnetic torque of the multiple magnetic torquers according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers includes: determining the constraint conditions for the magnetic torque according to the mapping relationship and the unloading magnetic moment; determining the objective function for optimization according to the energy consumption characteristics of the multiple magnetic torquers; and optimizing the size of the magnetic torque according to the constraint conditions and the objective function, wherein The operation of optimizing the size of the magnetic moment according to the constraint conditions and the objective function includes: randomly generating a plurality of solution vectors corresponding to the size of the magnetic moment according to the constraint conditions; substituting the plurality of solution vectors into the objective function respectively, and determining the objective function values ​​corresponding to the respective solution vectors; determining the minimum value corresponding to the objective function according to the objective function values ​​corresponding to the respective solution vectors; and iterating the plurality of solution vectors according to an iterative algorithm related to the minimum value of the objective function, and determining the size of the magnetic moment according to the optimal solution of the plurality of solution vectors when the conditions for iteration termination are met, wherein The plurality of magnetic torquers are three magnetic torquers respectively arranged on three axes of the satellite, and the constraint condition is: m 1, m 2, m 3≤ m r ;as well as ,in m 1. m 2 and m 3 are the magnitudes of the magnetic moments of the three magnetic torquers during the flywheel unloading process; m r is the rated magnetic moment of the three magnetic torquers; m u is an unloading magnetic moment for unloading the flywheel; and ψ i For the i The magnetic torque generated by the magnetic torquer m i Unloading moment m u The angle between The objective function is: ,in ρ is the resistivity of the coil wire of the magnetic torquer, μ e is the effective magnetic permeability of the magnetic bar of the magnetic torquer, N is the number of coil turns of the magnetic torquer, d is the diameter of the magnetic bar of the magnetic torquer, d w is the diameter of the coil wire of the magnetic torquer, where The iterative operation is performed on the multiple solution vectors according to an iterative algorithm corresponding to the minimum value of the objective function, including performing an iterative operation on the multiple solution vectors according to the following formula: V j k+1 = w j k + c 1* r 1*( Mbest j k - M j k )+ c 2* r 2*( Mbest k - M j k );as well as M j k+1 = M j k + V j k+1 ， in M j k and V j k Respectively expressed in k The solution vector determined by the iteration M j and the speed factor V j ; M j k+1 and V j k+1 Respectively expressed in k+ Solution vector determined by 1 iteration M j and the speed factor V j ; w is the inertia factor, which takes a non-negative value; c 1 and c 2 are learning factors, which are used to adjust the convergence speed of the algorithm; and r 1 and r 2 is a random number between 0 and 1, Mbest j k Indicated in k The historical optimal solution determined by the iteration, Mbest k Indicated in k Iteration Mbest j k The optimal solution in .

2. The method according to claim 1, characterized in that: The conditions for the iteration to terminate include: The number of iterations reaches a preset threshold; or After a predetermined number of consecutive iterations, the optimal function values ​​corresponding to the multiple solution vectors no longer change.

3. A storage medium, characterized in that: The storage medium includes a stored program, wherein when the program is run, the processor executes the method according to any one of claims 1 to 2.

4. A flywheel magnetic unloading device for a satellite, used to implement the method of claim 1, characterized in that: include: an angular momentum difference determination module, for determining an angular momentum difference between an actual angular momentum of the flywheel and a target angular momentum; An unloading magnetic moment determination module, used to determine an unloading magnetic moment for unloading the flywheel according to the angular momentum difference and the magnetic field strength of the earth's magnetic field; A mapping determination module, for determining a mapping relationship between the magnetic moment mapping of the magnetic moment to the magnetic moment component corresponding to the unloading magnetic moment according to the angle between the magnetic moment magnetic moment of a plurality of magnetic torquers provided on the satellite and the unloading magnetic moment; as well as An optimization module is used to optimize the magnetic torque of the multiple magnetic torquers according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers.

5. A flywheel magnetic unloading device for a satellite, used to implement the method of claim 1, characterized in that: include: processor; as well as A memory, connected to the processor, configured to provide the processor with instructions for processing the following processing steps: determining an angular momentum difference between an actual angular momentum of the flywheel and a target angular momentum; determining an unloading magnetic moment for unloading the flywheel according to the angular momentum difference and the magnetic field strength of the earth's magnetic field; Determine a mapping relationship between the magnetic moment of a plurality of magnetic torquers disposed on the satellite and the magnetic moment of the unloading magnetic moment and a magnetic moment component corresponding to the magnetic moment of the unloading magnetic moment; as well as The magnetic torques of the multiple magnetic torquers are optimized according to the mapping relationship and the energy consumption characteristics of the multiple magnetic torquers.

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