Satellite control system fault detection method based on energy and angular momentum cooperative monitoring

Abstract

A satellite control system fault detection method based on cooperative monitoring of energy and angular momentum comprises the following steps: firstly, setting a detection statistical period value, calculating a satellite average energy value, a theoretical angular momentum change value and a measurement angular momentum change value of each statistical period, then comparing the satellite average energy value, the theoretical angular momentum change value and the measurement angular momentum change value with a satellite average energy value of a previous statistical period, and scoring; comparing and grading the consistency of the theoretical angular momentum change value and the measured angular momentum change value, comprehensively judging the grading value, giving a satellite attitude control abnormity mark, and when the satellite attitude control abnormity is confirmed, performing subsequent processing to enable the satellite to autonomously switch into an attitude control safety capture mode.

Description

Technical Field

[0001] This invention relates to the field of spacecraft attitude control, and in particular to a fault detection method for satellite control systems based on the coordinated monitoring of energy and angular momentum, applicable to all spacecraft employing three-axis attitude stabilization control. Background Technology

[0002] With the development of satellite technology, the requirements for satellite autonomy and security are increasing. Current fault detection methods for satellite control systems typically monitor thresholds for important parameters such as attitude and angular velocity, determining an anomaly in the control system when either exceeds the threshold. However, this approach is overly mechanical, failing to fully utilize the dynamic nature of abnormal states. Furthermore, to avoid false positives, the thresholds are usually set too wide, leading to problems such as delayed anomaly detection and excessive jet propulsion consumption. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a fault detection method for satellite control systems based on the coordinated monitoring of energy and angular momentum. By comprehensively judging the abnormal state of satellite attitude control through the monitoring of the abnormality of the average energy value of the satellite and the consistency monitoring of the theoretical angular momentum change value and the measured angular momentum change value, the method can promptly detect abnormal states of satellite attitude control and improve the autonomous safety and survivability of the satellite.

[0004] The technical solution of this invention is: a fault detection method for a satellite control system based on coordinated monitoring of energy and angular momentum, comprising:

[0005] Set the detection and statistical cycle value, calculate the satellite average energy value, theoretical angular momentum change value, and measured angular momentum change value for each statistical cycle;

[0006] The calculated average satellite energy value for the current statistical period is compared and scored with the average satellite energy value for the previous statistical period. The consistency between the theoretical angular momentum change value and the measured angular momentum change value for the current statistical period is also compared and scored.

[0007] A comprehensive judgment is made based on the two scores. If a fault is found in the comprehensive judgment, an abnormal satellite attitude control flag is issued.

[0008] The preferred method for comparing and scoring satellite average energy values ​​is as follows:

[0009] If the average energy value E of the current statistical period <E norm Then let the average energy score ScoreE = 0;

[0010] If E≥E norm And EE last >E err If yes, then increment the average energy score ScoreE by 1; otherwise:

[0011] If E≥E norm And EE last ≤E err If the average energy score ScoreE is reduced by 1, and if ScoreE is less than 0 after the reduction, then ScoreE = 0.

[0012] Where E norm E represents the normal threshold for average energy values. last E represents the average energy value of the previous statistical period. err This is the threshold for the periodic change in the average energy value.

[0013] Preferably, the normal threshold value E for average energy is... norm The value of the average energy value E is determined based on a reasonable range and with a certain margin. For example, the 3σ value of the average energy value E under normal operating conditions is statistically analyzed, and 2 to 3 times it is taken as the normal threshold value E of the average energy value. norm The threshold for the periodic change of average energy value E err The value is determined based on a reasonable range of the change in the average energy value E before and after the beat, taking into account a certain margin. For example, the 3σ value of the change in the average energy value E before and after the beat under normal operating conditions is statistically analyzed, and 2 to 3 times it is taken as the threshold E of the periodic change in the average energy value before and after the beat. err In practice, adjustments may be required based on the actual situation.

[0014] Preferably, the consistency between the theoretical angular momentum change value and the measured angular momentum change value for the current statistical period is compared and scored as follows:

[0015] Let ΔH con,i i = 1, 2, 3 are the theoretical changes in angular momentum ΔH con The three components, ΔH meas,i i = 1, 2, 3 represents the measured change in angular momentum ΔH meas For the three components of i = 1, 2, 3, if |ΔH con,i |>ΔH thres,i And |ΔH meas,i -ΔH con,i |>K ΔH |ΔH con,i If |, then increment the consistency score ScoreH(i) by 1; otherwise, decrement the consistency score ScoreH(i) by 1. If ScoreH(i) is less than 0 after decrementing, then set ScoreH(i) = 0.

[0016] Where |·| represents taking the absolute value, ΔH thres,i i = 1, 2, 3 is the consistency threshold ΔH thres The three components, ΔH thres Given a 3*1 dimensional array, K ΔHScoreH(i), i = 1, 2, 3 are the three components of the consistency score ScoreH. ScoreH is a 3*1 dimensional array with an initial value of {0, 0, 0}.

[0017] Preferably, the consistency threshold ΔH thres,i According to |ΔH con,i The value of | is taken within a reasonable range and with a certain margin, for example, under normal operating conditions, |ΔH is statistically analyzed. con,i The 3σ value of | is taken as the consistency threshold ΔH, and 2 to 3 times it is used. thres,i Consistency coefficient K ΔH According to |ΔH meas,i -ΔH con,i | / |ΔH con,i The value of | is taken within a reasonable range and with a certain margin, for example, under normal operating conditions, |ΔH is statistically analyzed. meas,i -ΔH con,i | / |ΔH con,i The 3σ value of | is taken as the consistency coefficient K, and 2 to 3 times it is taken as the consistency coefficient K. ΔH In practice, adjustments may be required based on the actual situation.

[0018] Preferably, the comprehensive judgment is as follows:

[0019] like Then, reset ScoreE and ScoreH(i), i = 1, 2, 3 to zero, and give a satellite attitude control anomaly flag; K E K is the weighting coefficient for the energy score. H The two values ​​are weighting coefficients for angular momentum scores. Both are generally set to 1. If you do not want to introduce average energy value monitoring or angular momentum monitoring, one of them can be set to 0. Alternatively, you can adjust the relative weights of average energy value monitoring or angular momentum monitoring to other positive values ​​according to the actual situation. ScoreMax is the anomaly monitoring threshold, which can generally be a reasonable value between 3 and 10.

[0020] Preferably, the detection statistical period value T stat The setting needs to comprehensively consider the trade-off between eliminating measurement noise and timely monitoring of anomalies. If the setting value is too small, it is easily affected by measurement noise and will falsely trigger changes in the score. If the setting value is too large, the satellite will deviate too much from its stable state, resulting in increased nonlinear characteristics of the system and making it difficult to achieve timely monitoring. The statistical periodic value T for satellite detection in steady-state operation is... stat A reasonable value is generally between 10 and 50 seconds.

[0021] A fault detection system for a satellite control system based on coordinated monitoring of energy and angular momentum, comprising:

[0022] The variable calculation module sets the detection statistical cycle value, calculates the satellite's average energy value, theoretical angular momentum change value, and measured angular momentum change value in real time for each statistical cycle, and inputs them into the scoring module;

[0023] The scoring module compares and scores the average satellite energy value received in the current statistical period with the average satellite energy value in the previous statistical period, and compares and scores the consistency between the theoretical angular momentum change value and the measured angular momentum change value in the current statistical period. Finally, it inputs the two scores of the current statistical period into the comprehensive judgment module.

[0024] The comprehensive judgment module makes a comprehensive judgment based on the two scores. If the comprehensive judgment system malfunctions, it will give a satellite attitude control anomaly flag.

[0025] A computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of a fault detection method for a satellite control system based on coordinated monitoring of energy and angular momentum.

[0026] A computer software product includes: a processor and a storage device;

[0027] Storage device for storing one or more programs.

[0028] When the one or more programs are executed by one or more processors, the one or more processors implement the aforementioned fault detection method for a satellite control system based on coordinated monitoring of energy and angular momentum.

[0029] The advantages of this invention compared to the prior art are:

[0030] (1) This invention makes a comprehensive judgment by monitoring the anomalies in the average energy value of the satellite and the consistency between the theoretical angular momentum change value and the measured angular momentum change value, so as to detect abnormal states in the satellite attitude control in a timely manner and improve the satellite's autonomous safety and survivability.

[0031] (2) This invention provides a novel and practical method for detecting faults in a satellite control system by monitoring the rationality of the satellite's energy state and angular momentum state to determine the abnormal state of the satellite. Attached Figure Description

[0032] Figure 1 This is a flowchart of a fault detection method for a satellite control system based on the coordinated monitoring of energy and angular momentum, according to the present invention. Detailed Implementation

[0033] Example 1:

[0034] To enhance the autonomous safety detection capabilities of satellites, this invention presents a fault detection method for satellite control systems based on the coordinated monitoring of energy and angular momentum. By monitoring the rationality of changes in satellite energy values ​​and the consistency between changes in angular momentum and control expectations, abnormal states in satellite attitude control can be detected in a timely manner, allowing the satellite to switch to a safe acquisition mode, thereby improving its autonomous safety and survivability. Taking a low-Earth orbit satellite with an orbital inclination of approximately 90 degrees as an example... Figure 1 As shown, the specific steps of the present invention are as follows:

[0035] (1) First, set the detection statistical period value, calculate the satellite average energy value, theoretical angular momentum change value, and measured angular momentum change value for each statistical period; in this example, the detection statistical period value T is set. stat The duration is 20 seconds. Each statistical period is recorded from the start time T0 to the end time T0+T. stat The number of control cycles experienced during this period is N stat The average energy value E for this statistical period is calculated as follows:

[0036]

[0037] Where ω k For each control cycle, the angular velocity component of the satellite relative to the inertial coordinate system in the satellite's own system is represented by a 3*1 dimensional array, obtained from satellite attitude measurements. J0 represents the satellite's moment of inertia, a 3*3 dimensional matrix, based on satellite inertia measurement results. Δt is the control cycle length. Based on the control system configuration, Δt is set to 0.5 seconds, therefore N stat It is 40;

[0038] Calculate the theoretical change in angular momentum ΔH con The following is a 3*1 dimensional array:

[0039]

[0040] Where T c,k The theoretical control torque value for the satellite for each control cycle is a 3*1 dimensional array, calculated by the satellite control system. T d,k The estimated satellite interference moment for each control cycle is a 3*1 dimensional array, given by the satellite interference estimation calculation. × indicates cross product calculation.

[0041] Calculate the change in angular momentum ΔH meas The following is a 3*1 dimensional array:

[0042]

[0043] in ω0 represents the angular velocity component of the satellite relative to the inertial coordinate system in the satellite's own system during the last control period of this statistical cycle. It is a 3*1 dimensional array. ω0 represents the angular velocity component of the satellite relative to the inertial coordinate system in the satellite's own system during the last control period of the previous statistical cycle. It is also a 3*1 dimensional array. Both are given by satellite attitude measurement.

[0044] (2) Compare and score the average satellite energy value of the current statistical period with the average satellite energy value of the previous statistical period; if the average energy value of the current statistical period E <E norm If the average energy score is 0, then set the scoreE = 0; otherwise:

[0045] If E≥E norm And EE last >E err If yes, then increment the average energy score ScoreE by 1; otherwise:

[0046] If E≥E norm And EE last ≤E err If the average energy score ScoreE is reduced by 1, and if ScoreE is less than 0 after the reduction, then ScoreE = 0.

[0047] Here, E is taken as the normal range for satellite inertia and angular velocity. norm The value is 0.02, and E is taken as the normal range of the change in average energy value E before and after the beat. err It is 0.005.

[0048] (3) Compare and score the consistency between the theoretical and measured changes in angular momentum; record ΔH. con,i ,i=1,2,3 is ΔH con The three components, For ΔH meas For the three components of i = 1, 2, 3, if |ΔH con,i |>ΔH thres,i And |ΔH meas,i -ΔH con,i |>K ΔH |ΔH con,i If the consistency score is positive, then increment the consistency score ScoreH(i) by 1; otherwise, decrement the consistency score ScoreH(i) by 1. If the score after decrementing is less than 0, then set ScoreH(i) = 0.

[0049] Where |·| represents taking the absolute value, ΔH thres,i i = 1, 2, 3 is the consistency threshold ΔH thres The three components, ΔH thres This is a 3*1 dimensional array, and ΔH is set here according to the normal range of theoretical angular momentum change.thres =[0.03 0.15 0.15] T K ΔH The consistency coefficient is determined here based on |ΔH meas,i -ΔH con,i | / |ΔH con,i | Set K within a reasonable range ΔH =0.7, ScoreH(i), i=1,2,3 are the three components of the consistency score ScoreH. ScoreH is a 3*1 dimensional array with an initial value of {0,0,0}.

[0050] (4) Make a comprehensive judgment on the scores given in steps (2) and (3), and give a satellite attitude control anomaly flag. When the satellite attitude control anomaly is confirmed, the satellite is instructed to autonomously switch to attitude control safety acquisition mode; if K E *ScoreE+K H If ∑ScoreH(i)>ScoreMax, then:

[0051] i = 1, 2, 3

[0052] Set ScoreE and ScoreH(i), i = 1, 2, 3 to zero, give a satellite attitude control anomaly flag, and the satellite autonomously switches to attitude control safety acquisition mode.

[0053] Here, the average energy monitoring and angular momentum monitoring are given the same weight, i.e., K. E and K H All values ​​are set to 1, and the anomaly detection threshold, ScoreMax, is set to 5.

[0054] The above description is only the best specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the protection scope of the present invention.

[0055] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A fault detection method for a satellite control system based on coordinated monitoring of energy and angular momentum, characterized in that... include: Set the detection and statistical cycle value, calculate the satellite average energy value, theoretical angular momentum change value, and measured angular momentum change value for each statistical cycle; The calculated average satellite energy value for the current statistical period is compared and scored with the average satellite energy value for the previous statistical period. The consistency between the theoretical angular momentum change value and the measured angular momentum change value for the current statistical period is also compared and scored. A comprehensive judgment is made based on the two scores. If a fault is found in the comprehensive judgment, an abnormal satellite attitude control flag is issued.

2. The method according to claim 1, characterized in that: The average energy values ​​of the satellites are compared and scored as follows: If the average energy value E of the current statistical period <E norm Then let the average energy score ScoreE = 0; If E≥E norm And EE last >E err If yes, then increment the average energy score ScoreE by 1; otherwise: If E≥E norm And EE last ≤E err If the average energy score ScoreE is reduced by 1, and if ScoreE is less than 0 after the reduction, then ScoreE = 0. Where E norm E represents the normal threshold for average energy values. last E represents the average energy value of the previous statistical period. err This is the threshold for the periodic change in the average energy value.

3. The method according to claim 2, characterized in that: Normal threshold for average energy value E norm The average energy value E is selected based on a reasonable range and a certain margin. The 3σ value of the average energy value E under normal operating conditions is statistically analyzed, and 2 to 3 times it is taken as the normal threshold value E of the average energy value. norm The threshold for the periodic change of average energy value E err Based on the reasonable range of the change in average energy value E before and after the beat, and considering a certain margin, the value of 3σ of the change in average energy value E before and after the beat under normal operating conditions is statistically analyzed, and 2 to 3 times it is taken as the threshold E of the periodic change in average energy value before and after the beat. err In practice, adjustments may be required based on the actual situation.

4. The method according to claim 2, characterized in that: The consistency between the theoretical and measured angular momentum changes for the current statistical period is compared and scored as follows: Let ΔH con,i i = 1, 2, 3 are the theoretical changes in angular momentum ΔH con The three components, ΔH meas,i i = 1, 2, 3 represents the measured change in angular momentum ΔH meas For the three components of i = 1, 2, 3, if |ΔH con,i |>ΔH thres,i And |ΔH meas,i -ΔH con,i |>K ΔH |ΔH con,i If |, then increment the consistency score ScoreH(i) by 1; otherwise, decrement the consistency score ScoreH(i) by 1. If ScoreH(i) is less than 0 after decrementing, then set ScoreH(i) = 0. Where |·| represents taking the absolute value, ΔH thres,i i = 1, 2, 3 is the consistency threshold ΔH thres The three components, ΔH thres Given a 3*1 dimensional array, K ΔH ScoreH(i), i = 1, 2, 3 are the three components of the consistency score ScoreH. ScoreH is a 3*1 dimensional array with an initial value of {0, 0, 0}.

5. The method according to claim 4, characterized in that: Consistency threshold ΔH thres,i According to |ΔH con,i The value of |ΔH is taken within a reasonable range and with a certain margin, and the statistical results are obtained under normal operating conditions. con,i The 3σ value of | is taken as the consistency threshold ΔH, and 2 to 3 times it is used. thres,i Consistency coefficient K ΔH According to |ΔH meas,i -ΔH con,i | / |ΔH con,i The value of | is taken within a reasonable range and with a certain margin, for example, under normal operating conditions, |ΔH is statistically analyzed. meas,i -ΔH con,i | / |ΔH con,i The 3σ value of | is taken as the consistency coefficient K, and 2 to 3 times it is taken as the consistency coefficient K. ΔH In practice, adjustments may be required based on the actual situation.

6. The method according to claim 4, characterized in that: The comprehensive judgment is as follows: like Then, reset ScoreE and ScoreH(i), i = 1, 2, 3 to zero, and give a satellite attitude control anomaly flag; K E K is the weighting coefficient for the energy score. H is the weighting coefficient for the angular momentum score; ScoreMax is the anomaly detection threshold.

7. The method according to claim 1, characterized in that: The statistical periodic value T for satellite detection in steady-state operation stat Choose a reasonable value between 10 and 50 seconds.

8. A fault detection system for a satellite control system based on coordinated monitoring of energy and angular momentum, characterized in that... include: The variable calculation module sets the detection statistical cycle value, calculates the satellite's average energy value, theoretical angular momentum change value, and measured angular momentum change value in real time for each statistical cycle, and inputs them into the scoring module; The scoring module compares and scores the average satellite energy value received in the current statistical period with the average satellite energy value in the previous statistical period, and compares and scores the consistency between the theoretical angular momentum change value and the measured angular momentum change value in the current statistical period. Finally, it inputs the two scores of the current statistical period into the comprehensive judgment module. The comprehensive judgment module makes a comprehensive judgment based on the two scores. If the comprehensive judgment system malfunctions, it will give a satellite attitude control anomaly flag.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 7.

10. A computer software product, characterized in that... include: Processors and storage devices; Storage device for storing one or more programs. When the one or more programs are executed by one or more processors, the one or more processors implement the fault detection method for a satellite control system based on the coordinated monitoring of energy and angular momentum as described in any one of claims 1 to 7.

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