Method for calculating short-period output current of low-orbit satellite solar cell array in orbit
Patent Information
- Application Number
- CN202511988232.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-10-20
AI Technical Summary
[0007]本发明的目的在于克服上述现有技术的缺点，提供一种低轨卫星太阳电池阵在轨短周期输出电流的计算方法，主要用于解决现有方法因采用固定平均反照率假设而无法精确捕捉动态地球反照贡献、以及数据驱动模型依赖大量数据训练且物理机理不透明的问题，从而实现对低轨卫星在复杂空间环境下太阳电池阵输出电流精准计算的目的
本发明提供的计算方法，通过引入基于地理纬度的反照率空间分布模型和地–星–日动态几何判据筛选机制，实现了对低轨卫星所接受的地球反照辐照度随星下点位置变化的精确量化，从根本上解决了传统固定反照率假设无法捕捉地球反照动态变化的问题。经真实在轨卫星数据验证，采用本发明的计算方法后，电流计算的平均绝对误差（MAE）从传统温度修正方法的0.181A降低至0.055A，误差降低率达71.5%；均方根误差（RMSE）从0.271A降低至0.077A，误差降低率达69.3%，特别是在进出地影期间地球反照贡献显著变化的“双峰”时段，本发明方法有效抑制了传统温度修正方法出现的大幅度误差峰值，误差区间控制在[-0.15A,0.2A]内，这表明本发明不仅能显著提升计算精度，还具有更强的鲁棒性和可靠性。同时，本发明最终提供的计算模型基于物理机理构建，无需大量数据训练，适用于新卫星设计仿真、在轨实时能量管理等高可靠性应用场景。
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of satellite energy technology, specifically relating to a method for calculating the short-cycle output current of a low-orbit satellite solar cell array. Background Technology
[0002] Low-Earth orbit (LEO) satellites, with their low cost, high coverage, and rapid deployment and response capabilities, have demonstrated significant application value and broad development prospects in various fields such as Earth observation, communication, and scientific experiments. As the most important and reliable energy supply component in a satellite platform, the power generation performance of the solar array directly determines the satellite's operational lifespan and mission effectiveness. On-orbit current is one of the core parameters characterizing the power generation status of the solar array and supporting energy management and health assessment of the power system. Achieving accurate calculation of this current not only helps optimize the design and control strategies of the satellite energy system and improve energy utilization efficiency throughout its entire lifespan, but also has significant engineering implications for ensuring the long-term stable and reliable operation of the satellite.
[0003] The factors influencing the output current of satellite solar arrays are complex and diverse, primarily including ambient temperature, solar irradiance, solar illumination angle, Earth-Sun distance, Earth albedo, and space radiation. In short-period analysis (considering one orbital period), solar irradiance and Earth-Sun distance are generally considered relatively constant, and their contribution to the short-term variation characteristics of the output current is insignificant. However, for low-Earth orbit satellites that frequently cross Earth's shadow, the ambient temperature around the solar array undergoes drastic periodic changes; simultaneously, due to the rapid movement of the nadir point, the Earth albedo irradiance received by the satellite also exhibits significant dynamic fluctuations. Therefore, ambient temperature and Earth albedo become the two key dominant factors causing short-period variations in the on-orbit current of low-Earth orbit satellite solar arrays.
[0004] Currently, most related research focuses on the long-term performance degradation analysis of solar cell arrays in orbit. However, there is a lack of accurate and effective calculation methods for the output current fluctuation characteristics within short periods, especially those affected by dynamic changes in Earth's albedo. Existing methods for calculating and predicting in-orbit current can be mainly divided into two categories: First, the influencing factor fitting method. This method typically relies on empirical constants or average value assumptions (such as estimating Earth's albedo contribution using a fixed global average albedo). It cannot capture the spatial distribution differences and temporal fluctuations of Earth's albedo with variations in the geographic location of the nadir point and the type of the land surface, leading to significant systematic errors when the satellite is in different spatial positions, making it difficult to accurately reflect the short-period current variation patterns. Second, data-driven methods (such as machine learning-based models). While these methods may fit existing data, they require a large amount of high-quality telemetry data for training. Their generalization ability to new satellites, new orbits, or extreme conditions is weak, and the models lack clear physical mechanism support, requiring high computational resources and making them unsuitable for high-frequency, high-reliability real-time in-orbit calculations or rapid simulation scenarios.
[0005] In summary, establishing a method for calculating the short-cycle on-orbit current of low-Earth orbit satellite solar arrays that can accurately quantify the dynamic contribution of Earth's albedo has become a pressing technical problem to be solved in this field.
[0006] In view of this, this invention is hereby proposed. Summary of the Invention
[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for calculating the short-cycle output current of a low-Earth orbit satellite solar array. This method is mainly used to solve the problems of existing methods being unable to accurately capture the dynamic Earth albedo contribution due to the assumption of a fixed average albedo, and the data-driven model relying on a large amount of data for training and having an opaque physical mechanism. This method aims to achieve accurate calculation of the output current of a low-Earth orbit satellite solar array in a complex space environment.
[0008] The objective of this invention is achieved through the following technical solution: This invention provides a method for calculating the short-cycle output current of a low-Earth orbit satellite solar array, comprising the following steps: Step 1: Based on the working principle of the solar cell array, establish a basic expression for the output current of the solar cell array that takes into account the effect of temperature. Step 2: Based on the principle of diffuse reflection of the Lambertian body, establish an annual average model of the Earth's albedo according to latitude, and perform rasterization on a preset area of the Earth's surface to obtain the annual average of the Earth's albedo at each grid point. Step 3: Based on the Earth-satellite-sun positional relationship and the set geometric criteria, each grid point is judged, and the grid area formed by the grid points that meet all the criteria is dynamically selected as the effective Earth albedo area for the satellite solar array at the current moment. Step 4: Based on the effective spherical albedo region, derive the albedo irradiance of each grid point acting on the satellite solar cell array, and sum them as the total spherical albedo irradiance at the satellite's location; Step 5: Incorporate the total Earth albedo and solar irradiance into the basic expression, modify the basic expression, and obtain the final calculation model for the short-cycle output current of the low-orbit satellite solar cell array.
[0009] Furthermore, in step 1, the basic expression for the output current of the solar cell array is: In the formula: The base value for output current taking temperature effects into account; The total area of the solar cell array cells; The solar array is designed for the initial stage of its lifespan, with an incident angle of 0°, an operating temperature of 25°C, and a solar irradiance of 1353 W / m². 2 The on-orbit current density of the solar cell array at that time; The current temperature coefficient; This refers to the operating temperature of the battery array. The angle of incidence of the sun; The current irradiation attenuation factor; This is the current ultraviolet loss factor; This is the test error factor.
[0010] Furthermore, in step 2, the annual average model of Earth's albedo based on latitude is expressed as follows: In the formula: With the center latitude as The annual average of the Earth's albedo at the grid points; The number of days in a year; With the center latitude as The grid points in Earth's albedo at that time.
[0011] Furthermore, in step 2, the preset area on the Earth's surface is determined jointly based on the satellite orbital altitude and the latitude range of the nadir point, expressed as: In the formula: These represent the upper and lower limits of the latitude of the Earth covered by the satellite solar array's apparent location; These are the upper and lower limits of the latitude of the nadir point, respectively; The radius of the Earth; This represents the satellite's orbital altitude.
[0012] Furthermore, in step 3, the geometric criteria for judging each of the grid points include: (1) The grid points are located in the surface illumination area: ; (2) The grid points are located in the FOV region of the solar array: ; (3) The reflected light from the grid points reaches the surface of the solar cell array: ; The grid points that simultaneously satisfy conditions (1), (2), and (3) are identified as effective spherical albedo regions. In the formula: The vector pointing from the geocenter to the grid point; This is the vector pointing from the Earth's center to the Sun; The vector pointing from the satellite to the Earth's center Vector of satellite pointing to grid point The included angle; For the field of view; The vector pointing from the satellite to the grid point; This is the vector pointing from the satellite to the sun.
[0013] Furthermore, the field of view The expression is: In the formula: The radius of the Earth; This represents the satellite's orbital altitude.
[0014] Further, in step 4, the expression for the total Earth albedo irradiance is: In the formula: The number of grid points in the effective spherical albedo region at the current moment; For the first i The annual average albedo of the Earth at each grid point; This represents the current solar irradiance. The area of a single grid point; for and The angle between them; for and The angle between them; for Vector pointing from grid points to satellite The angle between them; For the first i The distance from each grid point to the satellite.
[0015] Furthermore, the area expression for a single grid region is: In the formula: The radius of the Earth; and These are the intervals for latitude and longitude, respectively. This is the center latitude of the grid point.
[0016] Furthermore, the following simplification is made when calculating the total Earth albedo: Approximating the direction of the reflected light as incident along the normal of the solar cell array, and assuming that the solar irradiance received by each surface illumination grid point is the same, the simplified expression is: .
[0017] Furthermore, in step 5, the final calculation model for the short-cycle output current of the low-orbit satellite solar array is expressed as follows: In the formula: The total Earth albedo irradiance obtained in step 4; This represents the current solar irradiance. The solar irradiance under standard test conditions is taken as 1353 W / m². 22 .
[0018] Compared with the prior art, the present invention has the following beneficial effects: The calculation method provided by this invention, by introducing a spatial distribution model of albedo based on geographic latitude and a dynamic geometric criterion screening mechanism between Earth, satellite, and sun, achieves accurate quantification of the variation of Earth's albedo irradiance received by low-Earth orbit satellites with the position of the nadir point. This fundamentally solves the problem that the traditional fixed albedo assumption cannot capture the dynamic changes in Earth's albedo. Verified with real in-orbit satellite data, the calculation method of this invention reduces the mean absolute error (MAE) of current calculation from 0.181A using the traditional temperature correction method to 0.055A, a reduction of 71.5%; the root mean square error (RMSE) decreases from 0.271A to 0.077A, a reduction of 69.3%. Particularly during the "double-peak" period when the contribution of Earth's albedo changes significantly between entering and leaving the Earth's shadow, this invention effectively suppresses the large error peaks that occur with the traditional temperature correction method, controlling the error range within [-0.15A, 0.2A]. This demonstrates that this invention not only significantly improves calculation accuracy but also possesses stronger robustness and reliability. Meanwhile, the computational model ultimately provided by this invention is built based on physical mechanisms, requiring no large amount of data for training, and is suitable for high-reliability application scenarios such as new satellite design simulation and on-orbit real-time energy management. Attached Figure Description
[0019] The accompanying drawings are incorporated in and form part of this specification, and together with the description serve to explain the principles of the invention.
[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] Figure 1 This is a flowchart illustrating the calculation method for the short-cycle output current of a low-orbit satellite solar cell array according to the present invention. Figure 2 This invention provides a comparative schematic diagram of the actual on-orbit current and the temperature-corrected current. Figure 3 The present invention provides a model for the annual average global albedo by latitude; Figure 4 A schematic diagram of the effective spherical albedo (FOV) of the solar cell array provided by the present invention; Figure 5 This invention provides a schematic diagram of the Earth-Star-Sun positional relationship and effective albedo. Figure 6 A schematic diagram comparing the results of the two calculation methods provided by this invention with actual telemetry data; Figure 7 This diagram illustrates the error comparison between the results of the two calculation methods provided by this invention and the actual telemetry data. Detailed Implementation
[0022] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples consistent with some aspects of the invention as detailed in the appended claims.
[0023] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.
[0024] The present invention provides a method for calculating the short-cycle output current of a low-Earth orbit satellite solar array. By accurately selecting the effective albedo region that affects the low-Earth orbit satellite solar array, establishing a calculation model of the Earth's albedo irradiance, and then modifying it by combining the basic expression of the solar array output current that takes into account the temperature effect, the accurate calculation of the short-cycle output current of the low-Earth orbit satellite solar array can be achieved.
[0025] This embodiment uses a low-Earth orbit satellite as an example. Its orbital parameters are: orbital inclination 41°, apogee 500km, perigee 450km. The method of this invention is used to calculate the short-cycle output current of its solar array in orbit. The specific steps are as follows: Step 1: Based on the working principle of the solar cell array, establish the following basic expression for the output current of the solar cell array, considering the effect of temperature: In the formula: The base value for output current taking temperature effects into account; The total area of the solar cell array cells; The solar array is designed for the initial stage of its lifespan, with an incident angle of 0°, an operating temperature of 25°C, and a solar irradiance of 1353 W / m².2 The on-orbit current density of the solar cell array at that time; The current temperature coefficient; This refers to the operating temperature of the battery array. The angle of incidence of the sun; The current irradiation attenuation factor; This is the current ultraviolet loss factor; This is the test error factor. Wherein, The specific values are given in the solar cell product manual, usually , , If the satellite's solar array is oriented towards the sun, then .
[0026] If only the effect of temperature on the output current of the solar cell array is considered, the calculation results are as follows: Figure 2 As shown, the result deviates significantly from the actual on-orbit current and cannot accurately reflect the "double-peak" short-period characteristics of the on-orbit current of the low-Earth orbit satellite solar array. This deviation is particularly pronounced during the satellite's entry and exit from the Earth's shadow, when the Earth's albedo changes drastically.
[0027] Step 2: Based on the principle of diffuse reflection of the Lambertian surface, establish an annual average model of the Earth's albedo according to latitude (e.g., Figure 3 As shown in the figure, the model is based on the fact that the surface albedo varies significantly with latitude and relatively gently with longitude. Therefore, by calculating the global albedo annual average by latitude, both modeling accuracy and computational efficiency can be balanced. Furthermore, the preset area of the Earth's surface is rasterized to obtain the annual average of the Earth's albedo at each grid point.
[0028] Specifically, first, establish an annual average model of Earth's albedo based on latitude, with the following expression: In the formula: With the center latitude as The annual average of the Earth's albedo at the grid points; The number of days in a year; With the center latitude as The grid points in Earth's albedo at that time.
[0029] Then, based on the satellite's orbital altitude and the latitude range of its nadir point, a predefined area on the Earth's surface is determined, expressed as: In the formula: These represent the upper and lower limits of the latitude of the Earth covered by the satellite solar array's apparent location; These are the upper and lower limits of the latitude of the nadir point, respectively; The radius of the Earth; This represents the satellite's orbital altitude.
[0030] In this embodiment, the satellite orbital inclination is 41°, therefore the upper limit of the nadir latitude is... The lower limit is Combined with Earth's radius Average track height After substituting the values into the formula, a surface area with latitude [-63°, 63°] and longitude [-180°, 180°] was selected as the analysis object. This area was then divided into 126×360 grids at 1°×1° intervals. The annual average albedo of each grid point was calculated based on its central latitude. Figure 3 Matching is obtained from the model shown.
[0031] like Figure 4 As shown, the FOV (Field of View) area is defined as the region of the Earth's surface that a solar array can receive albedo from. Its size depends on the satellite's orbital altitude. This region can be defined by the FOV angle (…). Quantitative description, , Geometrically defining the area of the Earth's surface from which the solar array can receive Earth's albedo radiation is a key parameter in the quantitative calculation of Earth's albedo irradiance. Calculations show that the average FOV angle of the satellite solar array in this embodiment is 136.78°.
[0032] Step 3: Based on the Earth-Satellite-Sun positional relationship, use the geometric criteria proposed in this invention to judge each grid point, and dynamically select the grid area formed by grid points that satisfy all criteria as the effective Earth albedo area for the satellite solar array at the current moment.
[0033] like Figure 5 As shown, for a certain moment t The satellite's orbital position and the sun's position are known. The following three geometric criteria are applied to each surface grid point: (1) The grid points are located in the surface illumination area: that is and The inner product is greater than 0, and the criterion expression is: This criterion ensures and The angle between the grid points is less than 90°, ensuring that all grid points receiving sunlight can be correctly identified. In other words, it ensures that the grid points are within the sunlight's reach, as only such grid points meet the prerequisite for generating albedo radiation.
[0034] (2) The grid points are located in the FOV region of the solar array: The criterion is that only when the surface grid points are within the FOV (Field of View) of the solar array can their albedo be received by the array. (3) The reflected light from the grid points reaches the surface of the solar cell array: that is and The inner product is greater than 0, and the criterion expression is: This criterion ensures that the direction of the reflected light from the effective grid points on the Earth's surface is within the effective receiving range of the solar array. In the formula: The vector pointing from the geocenter to the grid point; This is the vector pointing from the Earth's center to the Sun; The vector pointing from the satellite to the Earth's center Vector of satellite pointing to grid point The included angle; For the field of view; The vector pointing from the satellite to the grid point; This is the vector pointing from the satellite to the sun.
[0035] By using the above criteria to filter all surface grid points at a certain moment, the set of valid grid points that simultaneously meet all three criteria is identified as the effective Earth albedo region acting on the satellite solar array at the current moment.
[0036] Step 4: Based on Lambert's cosine law and the irradiance model of surface radiation on a micro-element surface, and combined with the effective Earth albedo area selected in Step 3, derive the Earth albedo irradiance acting on the satellite solar cell array at each grid point, and sum them as the total Earth albedo irradiance at the satellite's location.
[0037] Specifically, the expression for the Earth's total albedo irradiance is: In the formula: The number of grid points in the effective spherical albedo region at the current moment; For the first i The annual average albedo of the Earth at each grid point; This represents the current solar irradiance. The area of a single grid point; for and The angle between them; for and The angle between them; for Vector pointing from grid points to satellite The angle between them; For the first i The distance from each grid point to the satellite.
[0038] The area expression for a single grid region is: In the formula: The radius of the Earth; and These are the intervals for latitude and longitude, respectively. This is the center latitude of the grid point.
[0039] Furthermore, to balance computational complexity and modeling accuracy in engineering applications, and considering the physical characteristics of Earth's albedo and the relatively constant solar irradiance intensity over short periods, this invention makes two reasonable simplifications: first, the direction of the albedo light at the effective grid points is approximated as incident along the normal direction of the solar cell array; second, it is assumed that the solar irradiance received by each grid point on the surface of the illuminated area is the same. The simplified expression for the total Earth albedo irradiance is: .
[0040] Step 5: Incorporate the total Earth albedo and solar irradiance from Step 4 into the basic expression from Step 1, and modify the basic expression to obtain the final calculation model for the short-cycle output current of the low-orbit satellite solar cell array.
[0041] Specifically, the final calculation model expression for the short-cycle output current of the low-Earth orbit satellite solar array is as follows: In the formula: The total Earth albedo irradiance obtained in step 4; This represents the current solar irradiance. The solar irradiance under standard test conditions is taken as 1353 W / m². 2 .
[0042] Verification results Taking a complete orbital period of the satellite on March 20, 2024 (00:45-02:15) as an example, the calculation results of this invention are compared with the actual telemetry data measured by the satellite. The results are as follows: Figure 6 , Figure 7 As shown: Figure 6 The figures show a comparison curve between the calculation results of the method of this invention, the temperature-only correction method, and on-orbit telemetry data within the same orbital period. The results show that, compared to the traditional correction method that only considers temperature, the calculation results of the method of this invention significantly improve the agreement with the telemetry data throughout the entire orbital period. Especially in the AC and DF segments, where the current "double peak" is dominated by Earth's albedo contribution, the method of this invention can accurately capture the dynamic trend of current changes, fully reflecting the influence of the spatial distribution of the effective Earth albedo region on the output current of the solar array.
[0043] Figure 7The comparison shows the errors of the two calculation methods with measured data. The traditional temperature correction method exhibits significant error peaks during the current "double-peak" period, with a maximum error of 0.732A. The mean absolute error (MAE) for the entire cycle is 0.181A, and the root mean square error (RMSE) is 0.271A. In contrast, the improved model proposed in this invention maintains a consistently low calculation error throughout the entire orbital cycle, with the error range stably controlled within [-0.15A, 0.2A]. The full-cycle MAE is only 0.055A, a 71.5% reduction compared to the traditional method; the RMSE is only 0.077A, a 69.3% reduction compared to the traditional method. These comparative results fully verify the superiority of the calculation method of this invention: it not only possesses higher calculation accuracy throughout the entire orbital cycle but also effectively suppresses the large error peaks of the traditional method during periods of significant albedo contribution, significantly enhancing the robustness and reliability of the model.
[0044] In summary, the method for calculating the short-cycle output current of low-orbit satellite solar cell arrays provided by this invention has the advantages of high calculation accuracy, clear physical mechanism, and controllable calculation efficiency, which fully meets the performance simulation requirements of the new satellite design stage and the real-time energy management application scenarios during the on-orbit operation stage.
[0045] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention.
[0046] It should be understood that the present invention is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.
Claims
1. A method for calculating the short-cycle output current of a low-Earth orbit satellite solar cell array, characterized in that, Includes the following steps: Step 1: Based on the working principle of the solar cell array, establish a basic expression for the output current of the solar cell array that takes into account the effect of temperature. Step 2: Based on the principle of diffuse reflection of the Lambertian body, establish an annual average model of the Earth's albedo according to latitude, and perform rasterization on a preset area of the Earth's surface to obtain the annual average of the Earth's albedo at each grid point. Step 3: Based on the Earth-satellite-sun positional relationship and the set geometric criteria, each grid point is judged, and the grid area formed by the grid points that meet all the criteria is dynamically selected as the effective Earth albedo area for the satellite solar array at the current moment. Step 4: Based on the effective spherical albedo region, derive the albedo irradiance of each grid point acting on the satellite solar cell array, and sum them as the total spherical albedo irradiance at the satellite's location; Step 5: Incorporate the total Earth albedo and solar irradiance into the basic expression, modify the basic expression, and obtain the final calculation model for the short-cycle output current of the low-orbit satellite solar cell array.
2. The method for calculating the short-cycle output current of a low-orbit satellite solar array according to claim 1, characterized in that, In step 1, the basic expression for the output current of the solar cell array is: In the formula: The base value for output current taking temperature effects into account; The total area of the solar cell array cells; The solar array is designed for the initial stage of its lifespan, with an incident angle of 0°, an operating temperature of 25°C, and a solar irradiance of 1353 W / m². 2 The on-orbit current density of the solar cell array at that time; The current temperature coefficient; This refers to the operating temperature of the battery array. The angle of incidence of the sun; The current irradiation attenuation factor; This is the current ultraviolet loss factor; This is the test error factor.
3. The method for calculating the short-cycle output current of a low-orbit satellite solar cell array according to claim 1, characterized in that, In step 2, the annual average model of Earth's albedo based on latitude is expressed as follows: In the formula: With the center latitude as The annual average of the Earth's albedo at the grid points; The number of days in a year; With the center latitude as The grid points in Earth's albedo at that time.
4. The method for calculating the short-cycle output current of a low-orbit satellite solar array according to claim 1, characterized in that, In step 2, the preset area on the Earth's surface is determined based on the satellite orbital altitude and the latitude range of the nadir point, expressed as: In the formula: These represent the upper and lower limits of the latitude of the Earth covered by the satellite solar array's apparent location; These are the upper and lower limits of the latitude of the nadir point, respectively; The radius of the Earth; This represents the satellite's orbital altitude.
5. The method for calculating the short-cycle output current of a low-orbit satellite solar cell array according to claim 1, characterized in that, In step 3, the geometric criteria for judging each grid point include: (1) The grid points are located in the surface illumination area: ; (2) The grid points are located in the FOV region of the solar array: ; (3) The reflected light from the grid points reaches the surface of the solar cell array: ; The grid points that simultaneously satisfy conditions (1), (2), and (3) are identified as effective spherical albedo regions. In the formula: The vector pointing from the geocenter to the grid point; This is the vector pointing from the Earth's center to the Sun; The vector pointing from the satellite to the Earth's center Vector of satellite pointing to grid point The included angle; For the field of view; The vector pointing from the satellite to the grid point; This is the vector pointing from the satellite to the sun.
6. The method for calculating the short-cycle output current of a low-orbit satellite solar cell array according to claim 5, characterized in that, The field of view The expression is: In the formula: The radius of the Earth; This represents the satellite's orbital altitude.
7. The method for calculating the short-cycle output current of a low-orbit satellite solar cell array according to claim 1, characterized in that, In step 4, the expression for the total Earth albedo is: In the formula: The number of grid points in the effective spherical albedo region at the current moment; For the first i The annual average albedo of the Earth at each grid point; This represents the current solar irradiance. The area of a single grid point; for and The angle between them; for and The angle between them; for Vector pointing from grid points to satellite The angle between them; For the first i The distance from each grid point to the satellite.
8. The method for calculating the short-cycle output current of a low-orbit satellite solar cell array according to claim 7, characterized in that, The area expression for a single grid region is: In the formula: The radius of the Earth; and These are the intervals for latitude and longitude, respectively. This is the center latitude of the grid point.
9. The method for calculating the short-cycle output current of a low-orbit satellite solar cell array according to claim 7, characterized in that, The following simplifications are made when calculating the total Earth albedo: Approximating the direction of the reflected light as incident along the normal of the solar cell array, and assuming that the solar irradiance received by each surface illumination grid point is the same, the simplified expression is: 。 10. The method for calculating the short-cycle output current of a low-orbit satellite solar array according to claim 1, characterized in that, In step 5, the final calculation model for the short-cycle output current of the low-orbit satellite solar array is expressed as follows: In the formula: The total Earth albedo irradiance obtained in step 4; This represents the current solar irradiance. The solar irradiance under standard test conditions is taken as 1353 W / m². 2 .