On-orbit autonomous diagnosis method and system for geostationary satellite sailboard sun angle meter

Abstract

The present invention provides an on-orbit autonomous diagnosis method and system for a sailboard sun angle meter of a geostationary orbit satellite, comprising the following steps: step S1: performing wild value elimination processing on the current data measured by the sailboard sun angle meter; step S2: performing smoothing and filtering processing on the current wild value elimination data obtained in step one; step S3: performing solar tracking angle solution using the current smoothing and filtering data obtained in step two to obtain three groups of solar tracking angles; step S4: using the three groups of solar tracking angles obtained in step three as input, calculating the difference between the two and comparing them with the sun angle meter fault threshold to determine whether the sun angle meter is faulty; step S5: autonomously calculating the satellite illumination condition on the satellite, and when the satellite is in a shadow period, the solar angle meter is not autonomously diagnosed on the satellite. The present invention can be used for autonomous diagnosis of sailboard sun angle meter faults during the on-orbit period of a geostationary orbit satellite, timely discovering sailboard sun angle meter faults, ensuring that the solar array points to the sun in real time, and ensuring satellite energy security.

Description

Technical Field

[0001] The present invention relates to the general technical field of spacecraft, and in particular to an on-orbit autonomous diagnosis method and system for a sun angle meter of a geostationary orbit satellite sailboard. Background Art

[0002] Since the sun is a very bright point light source, it is easy to sense and identify, which greatly facilitates the design of sensors and the formulation of attitude determination algorithms. Therefore, solar sensors have become the preferred attitude sensing components of various spacecraft. Solar sensors can not only be used to measure the attitude of stellar bodies, but also can be directly used for positioning solar arrays and protecting star sensors. According to the technical requirements of the project, the field of view of the solar sensor can be designed to be a small field of view of a few minutes or a large field of view of 128°×128°, and the resolution can reach the order of seconds.

[0003] There are three basic types of solar sensors. The output signal of the sun appearance sensor (0-1 type solar sensor) is constant, indicating whether the sun appears in the field of view; the output signal of the analog solar sensor is a continuous function of the solar angle; the output signal of the digital solar sensor is a discrete function of the solar angle in coded form. The sailboard sun angle meter described in the method of the present invention belongs to the analog solar sensor, which has a field of view of several tens of degrees and an accuracy of up to ±1°, and is used for satellite solar arrays to capture and track the sun. This type of solar sensor has been widely used in FY-3, FY-4, GF-5 series satellite control systems and solar array tracking systems.

[0004] Whether the solar array can stably track the sun is related to the energy security of the satellite, and the working state of the sailboard sun angle meter, as the input of the sailboard closed-loop control of the sun, directly affects the sailboard's ability to track the sun. The method of the present invention is oriented to engineering practice, and uses the working principle and signal characteristics of the sailboard sun angle meter to propose an on-orbit autonomous diagnosis method for the sun angle meter of a geostationary orbit satellite. The present invention can be applied to the research and development process of satellite control systems or solar array tracking systems.

[0005] The patent application number is: CN201610081893.6, and the name is: A reliable solar panel autonomous tracking sun control method. It introduces the calculation of the target angle of the panel rotation based on the solar model and the satellite orbit, and the adjustment of the solar tracking angle through incremental adjustment and stop-hold method, but does not explain the on-orbit autonomous diagnosis method of the geostationary satellite panel sun angle meter.

[0006] The patent number is 2015106168439, and the name is "A dual-axis miniature analog solar sensor". It introduces a dual-axis miniature analog solar sensor and describes in detail the composition structure and working principle of the sensor, but does not explain the on-orbit autonomous diagnosis method of the geostationary satellite sailboard sun angle meter.

[0007] The patent number is 2017103386430, and its name is "A two-axis nano-precision solar sensor". It introduces a two-axis nano-precision solar sensor and describes in detail the composition structure and working principle of the sensor, but does not explain the on-orbit autonomous diagnosis method of the geostationary satellite sailboard sun angle meter.

[0008] Patent document CN107014398B (application number: 201710240152.2) discloses a method and device for detecting faults of a satellite simulated solar sensor, the method comprising: obtaining telemetry data of the simulated solar sensor in the current cycle; determining whether the satellite working mode in the current cycle is a preset mode according to the telemetry data; if it is a preset mode, calculating the predicted value of the output angle of the simulated solar sensor by a joint diagnosis method; judging whether the simulated solar sensor has a fault in the current cycle according to the predicted value and the telemetry value of the output angle included in the telemetry data. The embodiment of the present invention calculates the predicted value of the output angle by a joint diagnosis method, combines the predicted value and the telemetry value included in the telemetry data, quantitatively diagnoses whether a fault has occurred, promptly and quickly discovers abnormal changes in the telemetry data, and improves the accuracy and reliability of the satellite's on-orbit autonomous diagnosis and ground test data interpretation. Summary of the invention

[0009] In view of the defects in the prior art, the object of the present invention is to provide an on-orbit autonomous diagnosis method and system for a geostationary satellite sailboard sun angle meter.

[0010] According to the present invention, an on-orbit autonomous diagnosis method for a geostationary orbit satellite sailboard sun angle meter comprises:

[0011] Step S1: performing outlier elimination processing on the current data measured by the windsurfing sun angle meter to obtain current outlier elimination data;

[0012] Step S2: Smoothing and filtering the current wild-zone data to obtain current smoothing and filtering data;

[0013] Step S3: Calculate the sun tracking angle using the current smoothing filter data to obtain three sets of sun tracking angles;

[0014] Step S4: Calculate the difference between the three groups of sun tracking angles and compare them with the sun angle meter failure threshold to determine whether the sun angle meter is faulty.

[0015] Preferably, the windsurfing sun angle meter comprises: a preset number of solar cells and a light barrier; after the sunlight passes through the light barrier, it is irradiated on a preset number of solar cells, and the irradiated photosensitive area of ​​the solar cells changes with the incident angle of the sun, so that the output current of the preset number of solar cells changes accordingly.

[0016] Preferably, the solar tracking angle is used as a characterizing quantity of the relative relationship between the solar array and the sun, and the solar tracking angle is the angle between the projection of the sun direction vector on the XpOpZp plane and the normal line of the solar cell array.

[0017] Preferably, effective information in the sun angle meter output current measurement data is extracted by using methods of outlier elimination and smoothing filtering.

[0018] Preferably, the step S3 adopts: the control computer converts the four-channel current analog signals output by the sun angle meter into digital quantities through AD sampling; according to the characteristics of the sun angle meter, the four-channel current signals are resolved into three groups of sun tracking angles.

[0019] Preferably, the satellite illumination condition is calculated autonomously on board, and when the satellite is in a shadow period, the solar angle meter does not perform autonomous diagnosis on board.

[0020] Preferably, when the satellite is in the shadow area, the output current of each solar angle meter cell is zero, the solar angle meter output current cannot be used to solve the solar tracking angle, and the solar angle meter fault diagnosis cannot be performed, so the on-orbit autonomous fault diagnosis is not performed during the shadow period.

[0021] According to the present invention, an on-orbit autonomous diagnosis system for a geostationary orbit satellite sailboard sun angle meter comprises:

[0022] Module M1: removes outliers from the current data measured by the windsurfing sun angle meter to obtain current outlier data;

[0023] Module M2: smoothing and filtering the current wild-zone data to obtain current smoothing and filtering data;

[0024] Module M3: Current smoothing filter data is used to calculate the sun tracking angle to obtain three sets of sun tracking angles;

[0025] Module M4: Calculate the difference between the three sets of sun tracking angles and compare them with the sun angle meter fault threshold to determine whether the sun angle meter is faulty.

[0026] Preferably, the windsurfing sun angle meter comprises: a preset number of solar cells and a light barrier; after the sunlight passes through the light barrier, it is irradiated on the preset number of solar cells, and the irradiated photosensitive area of ​​the solar cells changes with the incident angle of the sun, so that the output current of the preset number of solar cells changes accordingly;

[0027] The solar tracking angle is a quantity representing the relative relationship between the solar array and the sun. The solar tracking angle is the angle between the projection of the sun direction vector on the XpOpZp plane and the normal line of the solar array.

[0028] Preferably, the satellite illumination condition is calculated autonomously on board, and when the satellite is in a shadow period, the solar angle meter does not perform autonomous diagnosis on board;

[0029] When the satellite is in the shadow area, the output current of each battery cell of the sun angle meter is zero. The output current of the sun angle meter cannot be used to calculate the solar tracking angle, and the sun angle meter fault diagnosis cannot be performed. Therefore, no on-orbit autonomous fault diagnosis is performed during the shadow period.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The on-orbit autonomous diagnosis method of the geostationary orbit satellite sailboard sun angle meter provided by the present invention utilizes the working principle and signal characteristics of the sailboard sun angle meter, obtains three sets of sailboard sun tracking angles according to three calculation methods, and judges whether the sun angle meter is working normally by comparing the relative relationship between the three sets of tracking angles. According to the diagnostic method provided by the present invention, there is no need for ground personnel to intervene, and the satellite can complete the diagnosis autonomously on-orbit, so that the fault can be discovered and countermeasures can be taken in the first time, ensuring that the satellite solar array can be aligned with the sun in real time, and ensuring the energy safety of the entire satellite. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0033] Figure 1 Schematic diagram of a windsurfing sun angle meter and its working principle.

[0034] Figure 2 This is a schematic diagram of the definition and installation location of the windsurfing sun angle meter signal.

[0035] Figure 3 This is the flow chart of the sun angle meter current signal elimination.

[0036] Figure 4 This is the flow chart of the smoothing filter of the sun angle meter current signal.

[0037] Figure 5 This is a sun angle meter fault diagnosis flow chart. DETAILED DESCRIPTION

[0038] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0039] Example 1

[0040] According to the present invention, an on-orbit autonomous diagnosis method for a geostationary orbit satellite sailboard sun angle meter comprises:

[0041] Step S1: performing outlier elimination processing on the current data measured by the windsurfing sun angle meter to obtain current outlier elimination data;

[0042] Step S2: Smoothing and filtering the current wild-zone data to obtain current smoothing and filtering data;

[0043] Step S3: Calculate the sun tracking angle using the current smoothing filter data to obtain three sets of sun tracking angles;

[0044] Step S4: Calculate the difference between the three groups of sun tracking angles and compare them with the sun angle meter failure threshold to determine whether the sun angle meter is faulty.

[0045] Preferably, the windsurfing sun angle meter comprises: a preset number of solar cells and a light barrier; after the sunlight passes through the light barrier, it is irradiated on a preset number of solar cells, and the irradiated photosensitive area of ​​the solar cells changes with the incident angle of the sun, so that the output current of the preset number of solar cells changes accordingly.

[0046] Preferably, the solar tracking angle is used as a characterizing quantity of the relative relationship between the solar array and the sun, and the solar tracking angle is the angle between the projection of the sun direction vector on the XpOpZp plane and the normal line of the solar cell array.

[0047] Preferably, effective information in the sun angle meter output current measurement data is extracted by using methods of outlier elimination and smoothing filtering.

[0048] Preferably, the step S3 adopts: the control computer converts the four-channel current analog signals output by the sun angle meter into digital quantities through AD sampling; according to the characteristics of the sun angle meter, the four-channel current signals are resolved into three groups of sun tracking angles.

[0049] Preferably, the satellite illumination condition is calculated autonomously on board, and when the satellite is in a shadow period, the solar angle meter does not perform autonomous diagnosis on board.

[0050] Preferably, when the satellite is in the shadow area, the output current of each solar angle meter cell is zero, the solar angle meter output current cannot be used to solve the solar tracking angle, and the solar angle meter fault diagnosis cannot be performed, so the on-orbit autonomous fault diagnosis is not performed during the shadow period.

[0051] According to the present invention, an on-orbit autonomous diagnosis system for a geostationary orbit satellite sailboard sun angle meter comprises:

[0052] Module M1: removes outliers from the current data measured by the windsurfing sun angle meter to obtain current outlier data;

[0053] Module M2: smoothing and filtering the current wild-zone data to obtain current smoothing and filtering data;

[0054] Module M3: Current smoothing filter data is used to calculate the sun tracking angle to obtain three sets of sun tracking angles;

[0055] Module M4: Calculate the difference between the three sets of sun tracking angles and compare them with the sun angle meter fault threshold to determine whether the sun angle meter is faulty.

[0056] Preferably, the windsurfing sun angle meter comprises: a preset number of solar cells and a light barrier; after the sunlight passes through the light barrier, it is irradiated on the preset number of solar cells, and the irradiated photosensitive area of ​​the solar cells changes with the incident angle of the sun, so that the output current of the preset number of solar cells changes accordingly;

[0057] The solar tracking angle is a quantity representing the relative relationship between the solar array and the sun. The solar tracking angle is the angle between the projection of the sun direction vector on the XpOpZp plane and the normal line of the solar array.

[0058] Preferably, the satellite illumination condition is calculated autonomously on board, and when the satellite is in a shadow period, the solar angle meter does not perform autonomous diagnosis on board;

[0059] When the satellite is in the shadow area, the output current of each battery cell of the sun angle meter is zero. The output current of the sun angle meter cannot be used to calculate the solar tracking angle, and the sun angle meter fault diagnosis cannot be performed. Therefore, no on-orbit autonomous fault diagnosis is performed during the shadow period.

[0060] Example 2

[0061] Embodiment 2 is a preferred embodiment of Embodiment 1

[0062] The present invention uses the 4-way output current of the windsurfing sun angle meter as input, utilizes its working principle and signal characteristics, obtains three groups of windsurfing sun tracking angles according to three calculation methods, and judges whether the windsurfing sun angle meter works normally by comparing the relative relationship between the three groups of tracking angles.

[0063] Specifically, the on-orbit autonomous diagnosis method of the geostationary orbit satellite sailboard sun angle meter provided by the present invention comprises the following steps:

[0064] Step S1: performing outlier elimination processing on the current data measured by the windsurfing sun angle meter.

[0065] Step S2: Smoothing and filtering the current filtering data obtained in step S1.

[0066] Step S3: Calculate the sun tracking angle using the current smoothing filter data obtained in step S2 to obtain three sets of sun tracking angles.

[0067] Step S4: using the three sets of sun tracking angles obtained in step S3 as input, calculating the difference between the two sets and comparing them with the sun angle meter fault threshold to determine whether the sun angle meter is faulty.

[0068] Step S5: The satellite illumination condition is calculated autonomously on board. When the satellite is in the shadow period, the solar angle meter does not perform autonomous diagnosis on board.

[0069] Specifically, step S1 includes: the windsurfing sun angle meter is composed of 4 solar cells and a light bar, as shown in the attached Figure 1 to Figure 2 As shown in the figure, after the sunlight passes through the light barrier, it shines on four solar cells. The irradiated photosensitive area of ​​the solar cells changes with the incident angle of the sun, so the output current of the four solar cells changes accordingly. m , m=a, b, c, d are used as input signals for de-wiping respectively. If the current signal of the current calculation cycle jumps compared with the previous cycle, the jump value and the current jump threshold ΔI gate If the current jump value is greater than the threshold value for ten consecutive calculation cycles, it is considered that the current jump has actually occurred and the current signal value is true. Otherwise, it is considered that the jump is an outlier and the current signal value of the previous cycle is maintained. Figure 3 As shown in the figure, I_in_now is the current output value of the sun angle meter in the current calculation cycle, I_out_last is the result after eliminating the wild fields in the previous calculation cycle, I_out_now is the result after eliminating the wild fields in the current calculation cycle, and Counter is the counter.

[0070] Preferably, step S2 comprises: taking the sun angle meter current culling signal obtained in step S1 as input, and taking the signal data of ten calculation cycles as filtering objects for mean filtering. The filtering process is shown in the attached figure. Figure 4 As shown in the figure, I_in_now is the sun tracking angle obtained after removing the wild, I_out_last is the result of smoothing and filtering in the previous calculation cycle, I_out_now is the result of smoothing and filtering in the current calculation cycle, Thita_Array is the filter queue, and Counter is the counter. The calculation method is as follows:

[0071]

[0072] Specifically, the step S3 includes: taking the filtered signal of the sun angle meter current obtained in step S2 as input, and converting the current value into the sun tracking angle according to the physical relationship, as shown in the following formula:

[0073]

[0074]

[0075]

[0076] In the formula, i a 、i b 、i c 、i d The output current of the four solar cells is respectively gate are the cell current and threshold, K1, K2, K3 are the solar tracking angle calculation coefficients, which can be calibrated through ground testing, and the default value is 1.

[0077] Specifically, step S4 includes: taking the three sets of sun tracking angles calculated in step S3 as input, respectively calculating the difference Δθ between each pair of them 12 , Δθ 23 , Δθ 31 , and the three differences are respectively compared with the sun angle meter fault threshold Δθ gate Comparison, each difference is less than the fault threshold Δθ gate When Δθ is 0, the sun angle meter is considered to be working properly and the calculation result of the sun tracking angle is available. 12 , Δθ 23 , Δθ 31 Any item is greater than the fault threshold Δθ for ten consecutive calculation cycles gate If the sun angle meter is abnormal, the sun tracking angle calculation result is unavailable. Figure 5 As shown in the figure, Thita_out is the output value of the solar tracking angle in the current calculation cycle, Thita_out_last is the output value of the solar tracking angle in the previous calculation cycle, Thita_as1 is the solar tracking angle obtained by calculation method 1 in the current calculation cycle, and Counter1 is a counter.

[0078] Preferably, step S5 comprises: the onboard control computer calculates the star-earth-sun and star-moon-sun relationships in real time according to the satellite orbit, solar orbit and lunar orbit to determine whether the satellite is in a shadow period.

[0079] The satellite-earth-sun angle can be calculated by the following formula:

[0080]

[0081] In the formula, is the geocenter-to-satellite vector, is the vector from the center of the earth to the sun.

[0082] The ground shadow threshold can be calculated by the following formula:

[0083]

[0084] In the formula, R earthis the radius of the Earth, R sun is the radius of the sun, R sat_earth is the distance between the star and the earth, R earth_sun is the distance between the Earth and the Sun.

[0085] The satellite-moon-sun angle can be calculated using the following formula:

[0086]

[0087] In the formula, is the moon-to-satellite vector, is the moon to sun vector.

[0088] The moon shadow threshold can be calculated by the following formula:

[0089]

[0090] In the formula, R moon is the radius of the moon, R sun is the radius of the sun, R sat_moon is the distance between the moon and the star, R moon_sun is the distance between the moon and the day.

[0091] When Ang Sat_Earth_Sun >UmbraGate||Ang Sat_Moon_Sun >When EclipseGate is established, the satellite is in the shadow area. When the satellite is in the shadow period, the autonomous fault diagnosis of the sailboard solar angle meter is not performed, and the first set of calculation results θ in step S3 is used. as1 As the sun tracking angle of the sailboard in the current cycle.

[0092] Those skilled in the art know that, in addition to implementing the system, device and its various modules provided by the present invention in a purely computer-readable program code, it is entirely possible to implement the same program in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers and embedded microcontrollers by logically programming the method steps. Therefore, the system, device and its various modules provided by the present invention can be considered as a hardware component, and the modules included therein for implementing various programs can also be considered as structures within the hardware component; the modules for implementing various functions can also be considered as both software programs for implementing the method and structures within the hardware component.

[0093] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. An autonomous on-orbit diagnosis method for a geostationary satellite sailboard sun angle meter, characterized in that: include: Step S1: performing outlier elimination processing on the current data measured by the windsurfing sun angle meter to obtain current outlier elimination data; Step S2: Smoothing and filtering the current wild-zone data to obtain current smoothing and filtering data; Step S3: Calculate the sun tracking angle using the current smoothing filter data to obtain three sets of sun tracking angles; Step S4: Calculate the difference between the three groups of sun tracking angles and compare them with the sun angle meter failure threshold to determine whether the sun angle meter is faulty.

2. The method for autonomous on-orbit diagnosis of a geostationary satellite sailboard sun angle meter according to claim 1, characterized in that: The windsurfing sun angle meter comprises: a preset number of solar cells and a light barrier; after the sunlight passes through the light barrier, it is irradiated on the preset number of solar cells, and the irradiated photosensitive area of ​​the solar cells changes with the incident angle of the sun, so that the output current of the preset number of solar cells changes accordingly.

3. The on-orbit autonomous diagnosis method for a geostationary orbit satellite sailboard sun angle meter according to claim 1, characterized in that: The solar tracking angle is a quantity representing the relative relationship between the solar array and the sun. The solar tracking angle is the angle between the projection of the sun direction vector on the XpOpZp plane and the normal line of the solar array.

4. The on-orbit autonomous diagnosis method for a geostationary orbit satellite sailboard sun angle meter according to claim 1, characterized in that: The effective information in the output current measurement data of the sun angle meter is extracted by using the methods of outlier elimination and smoothing filtering.

5. The on-orbit autonomous diagnosis method for a geostationary orbit satellite sailboard sun angle meter according to claim 1, characterized in that: The step S3 adopts: the control computer converts the four-way current analog signals output by the sun angle meter into digital quantities through AD sampling; according to the characteristics of the sun angle meter, the four-way current signals are resolved into three groups of sun tracking angles.

6. The on-orbit autonomous diagnosis method for a geostationary orbit satellite sailboard sun angle meter according to claim 1, characterized in that: The satellite illumination condition is calculated autonomously on board. When the satellite is in the shadow period, the solar angle meter does not perform autonomous diagnosis on board.

7. The method for autonomous on-orbit diagnosis of a geostationary satellite sailboard sun angle meter according to claim 6, characterized in that: When the satellite is in the shadow area, the output current of each battery cell of the sun angle meter is zero. The output current of the sun angle meter cannot be used to calculate the solar tracking angle, and the sun angle meter fault diagnosis cannot be performed. Therefore, no on-orbit autonomous fault diagnosis is performed during the shadow period.

8. An on-orbit autonomous diagnosis system for a geostationary satellite sailboard sun angle meter, characterized in that: include: Module M1: removes outliers from the current data measured by the windsurfing sun angle meter to obtain current outlier data; Module M2: smoothing and filtering the current wild-zone data to obtain current smoothing and filtering data; Module M3: Current smoothing filter data is used to calculate the sun tracking angle to obtain three sets of sun tracking angles; Module M4: Calculate the difference between the three sets of sun tracking angles and compare them with the sun angle meter fault threshold to determine whether the sun angle meter is faulty.

9. The on-orbit autonomous diagnosis system for the geostationary orbit satellite sailboard sun angle meter according to claim 8, characterized in that: The windsurfing sun angle meter comprises: a preset number of solar cells and a light barrier; after the sunlight passes through the light barrier, it is irradiated on the preset number of solar cells, and the irradiated photosensitive area of ​​the solar cells changes with the change of the incident angle of the sun, so that the output current of the preset number of solar cells changes accordingly; The solar tracking angle is a quantity representing the relative relationship between the solar array and the sun. The solar tracking angle is the angle between the projection of the sun direction vector on the XpOpZp plane and the normal line of the solar array.

10. The on-orbit autonomous diagnosis system for the geostationary orbit satellite sailboard sun angle meter according to claim 8, characterized in that: The satellite illumination condition is calculated autonomously on board. When the satellite is in the shadow period, the solar angle meter does not perform autonomous diagnosis on board. When the satellite is in the shadow area, the output current of each battery cell of the sun angle meter is zero. The output current of the sun angle meter cannot be used to calculate the solar tracking angle, and the sun angle meter fault diagnosis cannot be performed. Therefore, no on-orbit autonomous fault diagnosis is performed during the shadow period.

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