Spacecraft attitude control system and control method

Abstract

This invention relates to the field of spacecraft technology, and more particularly to a spacecraft attitude control system and control method. The spacecraft attitude control system includes momentum wheel equipment and control equipment. The momentum wheel equipment includes a first momentum wheel group, a second momentum wheel group, and a third momentum wheel group, respectively arranged on three orthogonal axes, and each group has two or more momentum wheels. The control equipment includes a power module, a control module, a data transmission module, and a data processing module. The advantages of this spacecraft attitude control system are: it can cover a wide range of satellite requirements, adapting to satellites of all weights and sizes; the number of momentum wheel models is reduced, leading to a reduction in production lines and supporting warehouses, which is beneficial for enterprise management and efficiency improvement; it achieves steady-state optimal control of the output torque of the momentum wheel group; and it adopts a parallel redundant decoupled design concept and method without single-machine backup, significantly improving system reliability without increasing system cost.

Description

Technical Field

[0001] This invention relates to the field of spacecraft technology, and in particular to a spacecraft attitude control system and control method. Background Technology

[0002] As the most crucial component for maintaining satellite attitude in orbit, traditional satellites primarily rely on momentum wheel configurations for attitude control and adjustment. Momentum wheel deployment methods include tri-orthogonal upright mounting, tri-orthogonal oblique mounting, and heterogeneous flywheel configurations. The selection of a momentum wheel is directly related to the satellite's size, weight, and configuration. The diverse needs of satellite attitude and orbit control result in a wide variety of momentum wheel models, numerous production lines, and a heavy R&D workload.

[0003] Traditional satellites have a momentum wheel configured along the axis requiring attitude control, while three-axis stabilized satellites have a momentum wheel configured along each of the three orthogonal axes, adjusting attitude by changing the speed of the momentum wheels. This control method, using a momentum wheel for each direction, has a single point of failure and low reliability; different satellite attitude and orbit control requirements result in numerous product models, hindering standardization, mass production, and low-cost manufacturing; momentum wheel selection relies on theoretical values ​​and approximate matching with existing product specifications, easily leading to resource waste; when new market demands emerge, product development is required, which is time-consuming, involves large investments, and is difficult to verify; high single-unit reliability requirements result in higher costs. Summary of the Invention

[0004] In view of this, the present invention aims to provide a spacecraft attitude control system that, based on a limited number of momentum wheels of different specifications, can adapt to satellites of different sizes, weights, and configurations through combinations of momentum wheels. This significantly reduces the number of momentum wheel models and production lines, and is of great significance for achieving standardized, mass production, and low-cost manufacturing. Employing momentum wheel assemblies to achieve on-orbit attitude stability control of spacecraft, and using momentum wheel combinations to achieve full coverage of satellite attitude and orbit control requirements, improves the reliability of the attitude and orbit control system, and facilitates the standardization, mass production, and low-cost manufacturing of momentum wheels.

[0005] To address the above problems, the present invention provides a spacecraft attitude control system, comprising: a momentum wheel device and a control device;

[0006] The momentum wheel device includes a first momentum wheel group, a second momentum wheel group, and a third momentum wheel group, which are respectively disposed on three orthogonal axes;

[0007] The first momentum wheel group, the second momentum wheel group, and the third momentum wheel group are each provided with two or more momentum wheels;

[0008] The control device includes a power module, a control module, a data transmission module, and a processing module;

[0009] The momentum wheel device is powered by the power module.

[0010] Data is transmitted between the processing module and the momentum wheel device through the data transmission module. The processing module obtains the state of the momentum wheel device after processing based on the information of the momentum wheel device and generates control commands.

[0011] The momentum wheel device is controlled by the control module according to the control commands.

[0012] Furthermore, the centers of the momentum wheels on each axis are located on the same straight line.

[0013] Furthermore, the planes containing the angular velocities of the momentum wheels on each axis are parallel to each other.

[0014] Furthermore, the vector directions of the moments of inertia of each momentum wheel on each axis are collinear.

[0015] Furthermore, the specifications of each momentum wheel are independent of each other.

[0016] Furthermore, the range of rotational inertia values ​​output by the combination of momentum wheels in each axial direction meets the attitude control requirements of the spacecraft.

[0017] Furthermore, the total moment of inertia M of the momentum wheel assembly all Compared to the moment of inertia M of a single momentum wheel i The relationship between them is determined by the following equation (1):

[0018] (1);

[0019] Among them, M all Let be the total momentum of all momentum wheels along the axis, j be the total number of momentum wheels along a single axis, and i be an integer 1 ≤ i ≤ j.

[0020] Furthermore, the typical values ​​for the moment of inertia of the momentum wheel are M, 2M, 5M, and 10M, and their angular momentum outputs cover 0~M, 0~2M, 0~5M, and 0~10M, respectively.

[0021] The maximum value of the system's angular momentum output is M max The system is configured as follows (2):

[0022] (2);

[0023] Where M true This is the actual control value of the system's angular momentum.

[0024] Furthermore, the attitude control reliability of the momentum wheel of the first momentum axis is: , where m is the total number of momentum wheels on the first momentum axis, and i is an integer 1≤i≤m;

[0025] The attitude control reliability of the momentum wheel of the second momentum axis is: , where n is the total number of momentum wheels on the first momentum axis, and j is an integer 1≤j≤n;

[0026] The attitude control reliability of the momentum wheel of the third momentum axis is: , where k is the total number of momentum wheels on the first momentum axis, and q is an integer 1≤q≤k.

[0027] A control method for a spacecraft attitude control system, wherein the spacecraft attitude control system is any one of the spacecraft attitude control systems described above, characterized in that it includes:

[0028] S100: The controller receives and parses the control command to obtain the target value and target time for the angular momentum adjustment. ;

[0029] S200, The controller reads the angular momentum value of the current momentum wheel assembly. Calculate the difference in momentum torque. Angular momentum adjustment time ;

[0030] S300, Calculate the rate of change of angular momentum. ;

[0031] S400, the controller reads the current angular momentum value of each momentum wheel. ;

[0032] S500, the controller calculates the adjustable amount of the angular momentum of each momentum wheel. ;

[0033] S600, with For the target value, the linear combination of momentum wheel adjustment amounts determined by the minimum path algorithm is as follows (3).

[0034] (3)

[0035] S700: The controller controls the momentum wheel assembly to adjust the speed, and adjusts the rate of momentum wheel adjustment through PID control.

[0036] The output of the S800 and momentum wheel assembly is stable at... .

[0037] Compared with existing technologies, the spacecraft attitude control system of the present invention has the following advantages:

[0038] The advantages of this technical solution are: it can cover a wide range of satellite needs, adapting to satellites of all weights and sizes, including large and ultra-large satellites; the number of momentum wheel models is reduced, which will correspondingly reduce production lines and supporting warehouses, thus benefiting enterprise management and improving efficiency; based on the minimum path control algorithm and momentum wheel PID control algorithm, steady-state optimal control of the output torque of the momentum wheel group is achieved; and the parallel redundant decoupled design concept and method without single-machine backup significantly improves system reliability without increasing system cost. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of a satellite attitude and orbit control system as described in an embodiment of this application;

[0040] Figure 2 This is a schematic diagram of the momentum wheel assembly system described in an embodiment of this application;

[0041] Figure 3 This is a schematic diagram of the linear combination of momentum wheels as described in an embodiment of this application;

[0042] Figure 4 This is a satellite deployment diagram of the momentum wheel assembly as described in an embodiment of this application;

[0043] Figure 5 This is a structural block diagram of the satellite attitude and orbit control system described in an embodiment of this application. Detailed Implementation

[0044] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0045] In this invention, the terms "first," "second," "upper," and "lower," etc., are used for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," "upper," or "lower" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. Where the technical solutions of the embodiments can be combined, they are all within the scope of protection claimed by this invention.

[0046] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0047] like Figure 1As shown, a spacecraft attitude control system includes a momentum wheel device and a control device. The momentum wheel device includes a first momentum wheel group, a second momentum wheel group, and a third momentum wheel group, which are respectively disposed on three orthogonal axes. Each of the first, second, and third momentum wheel groups has two or more momentum wheels. Figure 5 As shown, the control device includes a power supply module, a control module, a data transmission module, and a processing module. The power supply module supplies power to the momentum wheel device. The data transmission module transmits data between the processing module and the momentum wheel device. The processing module processes information from the momentum wheel device to obtain its state and generates control commands. The control module controls the momentum wheel device according to these control commands.

[0048] The attitude control system constructed with the above structure consists of a momentum wheel assembly composed of multiple momentum wheels. The maximum output value of the momentum wheel assembly is the sum of the maximum output values ​​of each momentum wheel. The adjustment accuracy of the momentum wheel assembly is the adjustment accuracy of the most accurate momentum wheel. If a single momentum wheel fails, the momentum wheel assembly will be degraded for use.

[0049] like Figure 5 As shown, the control device has power supply, communication, and computing functions. On the one hand, it converts the power supply from the satellite platform to the local power supply through the built-in power supply module to provide energy for the momentum wheel; on the other hand, it communicates with the satellite platform to obtain control commands, completes command parsing, controls the output adjustment of the momentum wheel, collects the status of the momentum wheel, and feeds the information back to the satellite platform.

[0050] The control equipment has the following characteristics:

[0051] 1) The communication connectors for the control equipment use serial bus communication.

[0052] 2) The control equipment communication connector communicates with the satellite platform control computer to receive control commands;

[0053] 3) The control equipment communication connector communicates with the satellite platform control computer to transmit the status parameters of the upper transmission quantity wheel;

[0054] 4) The control device communication connector can communicate with multiple momentum wheels simultaneously;

[0055] 5) The control device communication connector can simultaneously send control commands to multiple momentum wheels;

[0056] 6) The control equipment communication connector can simultaneously collect the state parameters of multiple momentum wheels;

[0057] 7) The power connector for the control equipment receives power from the satellite platform;

[0058] 8) The power connector for the control equipment supports multiple power supply systems to supply power to the momentum wheel;

[0059] 9) The control equipment processing module parses the control commands received by the interface plug-in;

[0060] 10) The control equipment processing module optimizes the configuration of state parameters for each momentum wheel according to the control instructions;

[0061] 11) The momentum wheel state parameters collected by the control equipment processing module interface plug-in are packaged together;

[0062] 12) The power module of the control equipment performs filtering, transformation, and other processing on the voltage input to the connector plug;

[0063] 13) The power module of the control equipment supplies power to each momentum wheel through connectors;

[0064] 14) The control equipment processing module collects the status parameters of the power module and packages them;

[0065] 15) The control device does not process the module control power module and controls the output of each port.

[0066] like Figure 2 As shown, the first momentum axis, the second momentum axis, and the third momentum axis are three orthogonal axes that require the satellite platform to maintain stability or perform attitude control. m, n, and k are independent of each other and represent the total number of momentum wheels installed on each axis. The momentum wheels in each momentum wheel group are coded. Momentum wheels with different codes can use the same model or different models of momentum wheels.

[0067] The attitude control system of this application features a parallel, redundant, and decoupled design for the momentum wheel assembly, with each momentum wheel operating independently. Under normal operating conditions, the maximum output capability of a single-axis system is the sum of the maximum outputs of all momentum wheels on that axis. When a single momentum wheel in the momentum wheel assembly fails, the system can still maintain operation, and it retains attitude control capability even under degraded operating conditions.

[0068] Compared to traditional cold backup and hot backup designs, the attitude control system in this application does not require a dedicated backup unit, and the system's reliability increases with the number of momentum wheels. If the reliability of a single momentum wheel unit is R, and failure is defined as a complete lack of output from the momentum axis, then the reliability of the momentum wheel assembly is... Its reliability is far superior to traditional redundant designs. It covers a wide range of satellite requirements, adapting to satellites of all weights and sizes, including large and ultra-large satellites. The reduction in momentum wheel models leads to a corresponding reduction in production lines and supporting warehouses, which is beneficial for enterprise management and efficiency improvement. Based on the minimum path control algorithm and momentum wheel PID control algorithm, steady-state optimal control of the momentum wheel output torque is achieved. Adopting a parallel redundant decoupled design concept and method without single-machine backup, system reliability is significantly improved without increasing system cost.

[0069] like Figure 3 As shown, momentum wheels are combined to form momentum wheel sets, and the technical parameters of the momentum wheel sets can cover all the momentum wheel requirements of satellites.

[0070] Furthermore, the centers of the momentum wheels on each axis are located on the same straight line.

[0071] Furthermore, the planes containing the angular velocities of the momentum wheels on each axis are parallel to each other.

[0072] Furthermore, the vector directions of the moments of inertia of each momentum wheel on each axis are collinear.

[0073] Furthermore, the specifications of each momentum wheel are independent of each other, and there are no hard constraints between them.

[0074] Furthermore, the range of rotational inertia values ​​output by the combination of momentum wheels in each axial direction meets the attitude control requirements of the spacecraft.

[0075] The maximum value j of the momentum wheel combination is in principle unconstrained. Therefore, the range Mmax of the rotational inertia value output after the momentum wheel combination in this axis direction can meet the attitude control requirements of any large spacecraft.

[0076] Furthermore, the total moment of inertia M of the momentum wheel assembly all Compared to the moment of inertia M of a single momentum wheel i The relationship between them is determined by the following equation (1):

[0077] (1);

[0078] Among them, M all Let be the total momentum of all momentum wheels along the axis, j be the total number of momentum wheels along a single axis, and i be an integer 1 ≤ i ≤ j.

[0079] Furthermore, the typical values ​​for the moment of inertia of the momentum wheel are M, 2M, 5M, and 10M, and their angular momentum outputs cover 0~M, 0~2M, 0~5M, and 0~10M, respectively.

[0080] The maximum value of the system's angular momentum output is M max The system is configured as follows (2):

[0081] (2);

[0082] Where M true This is the actual control value of the system's angular momentum.

[0083] Using a momentum wheel with typical parameters as the reference unit, the linear superposition of the reference unit according to actual control requirements can achieve full coverage of the momentum angular momentum requirement. The on-board deployment effect of the momentum wheel assembly is as follows: Figure 4 As shown.

[0084] The deployment of momentum wheel assemblies on satellites has the following characteristics:

[0085] The first momentum axis, the second momentum axis, and the third momentum axis are orthogonal. The sum of the moment of inertia vectors of the momentum wheels on the first momentum axis, the second momentum axis, and the third momentum axis coincides with the first momentum axis, the second momentum axis, and the third momentum axis, respectively.

[0086] The range of angular momentum that the momentum wheel assembly of the first momentum axis can output:

[0087] ,

[0088] The control precision is no less than that of the momentum wheel with the highest precision among the momentum wheels, where m is the total number of momentum wheels on the first momentum axis, and i is an integer 1≤i≤m.

[0089] The range of angular momentum that the momentum wheel assembly of the second momentum axis can output is:

[0090] ,

[0091] The control precision is no less than that of the momentum wheel with the highest precision among the momentum wheels, where n is the total number of momentum wheels on the first momentum axis, and j is an integer 1≤j≤n.

[0092] The range of angular momentum that the momentum wheel assembly of the second momentum axis can output is:

[0093] ,

[0094] The control precision is no less than that of the momentum wheel with the highest precision among the momentum wheels, where k is the total number of momentum wheels on the first momentum axis, and q is an integer 1≤q≤k.

[0095] Each momentum wheel is independently powered and controlled, with no coupling between them.

[0096] When a single momentum wheel fails, this axis still retains some attitude control capability and should be used in a downgraded manner.

[0097] Furthermore, the attitude control reliability of the momentum wheel of the first momentum axis is: ;

[0098] The attitude control reliability of the momentum wheel of the second momentum axis is: ;

[0099] The attitude control reliability of the momentum wheel of the third momentum axis is: .

[0100] A control method for a spacecraft attitude control system, wherein the spacecraft attitude control system is any one of the spacecraft attitude control systems described above, characterized in that it includes:

[0101] S100: The controller receives and parses the control command to obtain the target value and target time for the angular momentum adjustment. ;

[0102] S200, The controller reads the angular momentum value of the current momentum wheel assembly. Calculate the difference in momentum torque. Angular momentum adjustment time ;

[0103] S300, Calculate the rate of change of angular momentum. ;

[0104] S400, the controller reads the current angular momentum value of each momentum wheel. ;

[0105] S500, the processing module calculates the adjustable amount of angular momentum for each momentum wheel. ;

[0106] S600, with For the target value, the linear combination of momentum wheel adjustment amounts determined by the minimum path algorithm is as follows (3).

[0107] (3)

[0108] S700: The controller controls the momentum wheel assembly to adjust the speed, and adjusts the rate of momentum wheel adjustment through PID control.

[0109] The output of the S800 momentum wheel assembly is stable at M0.

[0110] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A spacecraft attitude control system, characterized in that, include: Momentum wheel equipment and control equipment; The momentum wheel device includes a first momentum wheel group, a second momentum wheel group, and a third momentum wheel group, which are respectively disposed on three orthogonal axes; The first momentum wheel group, the second momentum wheel group, and the third momentum wheel group are each provided with two or more momentum wheels; The control device includes a power module, a control module, a data transmission module, and a data processing module; The momentum wheel device is powered by the power module. Data is transmitted between the processing module and the momentum wheel device through the data transmission module. The processing module obtains the state of the momentum wheel device after processing based on the information of the momentum wheel device and generates control commands. The momentum wheel device is controlled by the control module according to the control commands.

2. The spacecraft attitude control system according to claim 1, characterized in that, The centers of the momentum wheels on each axis are located on the same straight line.

3. The spacecraft attitude control system according to claim 1, characterized in that, The planes containing the angular velocities of the momentum wheels on each axis are parallel to each other.

4. The spacecraft attitude control system according to claim 1, characterized in that, The vector directions of the moments of inertia of each momentum wheel on each axis are collinear.

5. The spacecraft attitude control system according to claim 1, characterized in that, The specifications of each momentum wheel are independent of each other.

6. The spacecraft attitude control system according to any one of claims 1-5, characterized in that, The range of rotational inertia values ​​output by the combination of momentum wheels in each axial direction meets the attitude control requirements of spacecraft.

7. The spacecraft attitude control system according to claim 6, characterized in that, The total moment of inertia M of the momentum wheel assembly all Compared to the moment of inertia M of a single momentum wheel i The relationship between them is determined by the following equation (1): （1）； Among them, M all Let be the total momentum of all momentum wheels along the axis, j be the total number of momentum wheels along a single axis, and i be an integer 1 ≤ i ≤ j.

8. The spacecraft attitude control system according to claim 7, characterized in that, The typical values ​​for the moment of inertia of the momentum wheel are M, 2M, 5M, and 10M, and its angular momentum output covers 0~M, 0~2M, 0~5M, and 0~10M, respectively. The maximum value of the system's angular momentum output is M max The system is configured as follows (2): （2）； Where M true This is the actual control value of the system's angular momentum.

9. The spacecraft attitude control system according to claim 7, characterized in that, The attitude control reliability of the momentum wheel of the first momentum axis is: , where m is the total number of momentum wheels on the first momentum axis, and i is an integer 1≤i≤m; The attitude control reliability of the momentum wheel of the second momentum axis is: , where n is the total number of momentum wheels on the first momentum axis, and j is an integer 1≤j≤n; The attitude control reliability of the momentum wheel of the third momentum axis is: , where k is the total number of momentum wheels on the first momentum axis, and q is an integer 1≤q≤k.

10. A control method for a spacecraft attitude control system, wherein the spacecraft attitude control system is the spacecraft attitude control system as described in any one of claims 1-9, characterized in that, include: S100: The controller receives and parses the control command to obtain the target value and target time for the angular momentum adjustment. ; S200, The controller reads the angular momentum value of the current momentum wheel assembly. Calculate the difference in momentum torque. Angular momentum adjustment time ; S300, Calculate the rate of change of angular momentum. ; S400, the controller reads the current angular momentum value of each momentum wheel. ; S500, the controller calculates the adjustable amount of the angular momentum of each momentum wheel. ; S600, with For the target value, the linear combination of momentum wheel adjustment amounts determined by the minimum path algorithm is as follows (3). （3） S700: The controller controls the momentum wheel assembly to adjust the speed, and adjusts the rate of momentum wheel adjustment through PID control. The output of the S800 and momentum wheel assembly is stable at... .

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