Satellite power system energy balance analysis method

Abstract

The application discloses a kind of satellite power supply system energy balance analysis methods, comprising the following steps: S1: based on Matlab establishes the model of solar cell array, battery, power regulation and control unit PCU, platform and load power equipment, realize the simulation for satellite power supply system energy flow process;S2: using Matlab GUI develops graphical user interface, provides satellite power supply system energy balance analysis tool and the interactive interface of power system designer;S3: by designer in the graphical user interface through interactive interface input current power system design scheme, and the power requirement data of power equipment;S4: according to the input data in step S3, by simulating energy flow state, the energy balance of satellite energy storage equipment in a certain period of time is analyzed and judged, and the curve and conclusion of energy balance analysis are given.The method can improve the calculation accuracy, efficiency and visualization level of power system energy balance analysis, and improve the digital level in satellite development process.

Description

Technical Field

[0001] This invention belongs to the field of satellite power supply and distribution subsystem design, and mainly relates to a method for energy balance analysis of satellite power systems applicable to complex orbits and operating conditions. Background Technology

[0002] Functionally, satellite power systems generally consist of power generation, energy storage, regulation and control, and power distribution equipment. On most satellites, these correspond to solar arrays, batteries, power regulation and control units, and platform and payload power distribution units, respectively. The electrical energy generated by the power generation equipment under sunlight is processed by the regulation and control unit to produce a stable power bus. The power bus then distributes and controls the power to the consuming equipment. When the power output from the power generation equipment is insufficient, the energy storage equipment releases electrical energy to supplement the power bus.

[0003] The energy balance of a satellite power system refers to the ability of the power system to provide electrical energy to electrical equipment that meets its power demand and characteristics at each stage, while the energy consumption and replenishment of energy storage devices are balanced within a cycle. This is a necessary condition for the continuous and stable operation of a satellite.

[0004] Analyzing the energy balance of a satellite power system under a given design scheme is crucial during the design phase. However, for satellites of certain purposes and orbits, illumination conditions, satellite attitude, payload equipment operating conditions, and power demands are interconnected, rendering traditional energy balance analysis methods based on worst-case scenarios inapplicable. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a satellite power system energy balance analysis method based on a graphical user interface, providing power system designers with a user-friendly software tool, improving the calculation accuracy, efficiency, and visualization level of power system energy balance analysis, and enhancing the digitalization level in the satellite development process.

[0006] To achieve the above objectives, the present invention adopts the following solution:

[0007] This invention provides a method for energy balance analysis of a satellite power system, comprising the following steps:

[0008] S1: Based on Matlab, models of solar cell array, battery, power regulation and control unit (PCU), platform and payload electrical equipment are established to simulate the energy flow process of the satellite power system;

[0009] S2: Develop a graphical user interface using Matlab GUI to provide an interactive interface for satellite power system energy balance analysis tools and power system designers;

[0010] S3: The designer inputs the current power system design scheme and the power demand data of the electrical equipment through the interactive interface of the graphical user interface;

[0011] S4: Based on the data input in step S3, analyze and judge the energy balance of the satellite energy storage device over a certain period of time by simulating the energy flow state, and give the energy balance analysis curve and conclusion.

[0012] Furthermore, in step S1,

[0013] The solar cell array model includes parameters such as the number of arrays, cell efficiency, size, and number of series and parallel connections;

[0014] The battery model includes parameters such as individual cell capacity, number of series and parallel connections, and capacity decay rate.

[0015] The power regulation and control unit model includes battery charging and discharging management and protection logic, as well as different bus systems, including bus regulation methods and operating efficiency parameters of the charging and discharging units;

[0016] The platform and load power equipment models include load power and power distribution loss parameters.

[0017] Furthermore, in step S3, the user inputs the design parameters of the power system, including the selection and configuration of the battery, PCU, and solar array.

[0018] Battery parameters include: number of battery packs, cell type, internal resistance of battery pack, number of cells connected in series, series-parallel connection, whether battery failure is considered, initial state of charge of the battery at the start of the simulation, nominal capacity of a single pack, factory test capacity of a single pack, capacity decay rate, self-discharge coefficient, and state of charge range during the sunlight season.

[0019] PCU parameters include: bus regulation system, BCR efficiency, BDR efficiency, constant current charging level during the solar season, and constant current charging level during the shadow season.

[0020] Solar cell array parameters include: number of cell strings, whether cell failure is considered, degradation rate, number of subarrays, number of parallel arrays per array, cell type, and cell size.

[0021] Furthermore, in step S4, the conclusion includes waveforms displaying the analysis results, including waveforms of the output power and load power of the solar cell array, waveforms of the charging and discharging current of the energy storage device, waveforms of the discharge depth of the energy storage device, and waveforms of the voltage of the energy storage device. These waveforms allow for a direct assessment of whether the energy of the energy storage device in the satellite power system is balanced.

[0022] Furthermore, the energy storage device is a battery.

[0023] Furthermore, before step S1, the following steps are also included: selecting a simulation analysis mode, which includes three modes: external import simulation, daily simulation, and annual simulation.

[0024] Furthermore, in the external import mode, both the solar cell array power data and the load power data are read from an external data file, and the simulation time depends on the time step and the data length. In the other two modes, the simulation time is 24 hours and one year, respectively, and only the load power data is read from an external data file. The time step for all three modes is determined by the designer according to the format of the data file, ranging from 1 second to 1 hour.

[0025] In single-day simulation mode, designers can choose whether to consider solar panel shading as needed. If so, the tool can set the shading coefficient and shading time. During the shading period, the solar panel output power will be reduced by the coefficient. In single-day simulation mode, the ground shadow time can be customized. During the ground shadow time, the solar panel output power will be set to 0.

[0026] In the one-year simulation mode, the tool will automatically set the ground shadow situation based on the geostationary orbit shadow situation, that is, the ground shadow is the longest on the spring and autumn equinoxes, with a length of 72 minutes, and the ground shadow length is 45 days in spring and autumn, and the length of the ground shadow is gradually increasing and then gradually decreasing within 45 days; this mode does not consider occlusion.

[0027] Furthermore, in step S1, when establishing the solar cell array model,

[0028] In external import mode, the output power data of the solar cell array is read directly from an external data file;

[0029] In single-day or year-long simulation modes, the output power data of the solar array is calculated based on the solar array selection and configuration parameters, as well as the current Earth-Sun distance and solar incidence angle. During the illumination period, the output power of the solar array equals the product of the bus voltage and the output current. The bus voltage equals the user-defined desired value. Vm, Im, Voc, and Isc represent the voltage, current, open-circuit voltage, and short-circuit current at the maximum power point, respectively. These four parameters are determined by the area and material of the solar cells and are affected by temperature, light intensity, etc. The four parameters Vm, Im, Voc, and Isc determine the shape of the solar array's VI curve. The output current of the solar array is derived from points on the VI curve; for each bus voltage, a corresponding solar array output current can be obtained.

[0030] Furthermore, in step S1, when establishing the battery model,

[0031] The method for calculating the battery charging current Ich during the sunshine period is as follows:

[0032] Ich=(Psa-Pload)*η1 / Vbat (1)

[0033] Where Psa is the output power of the solar cell array, Pload is the load power, Vbat is the battery terminal voltage, and η1 is the PCU charging efficiency.

[0034] Method for calculating the battery discharge current Idis during the shadow period:

[0035] Idis = Pload / η2 / Vbat (2)

[0036] Where η2 is the PCU discharge efficiency;

[0037] Method for calculating battery pack voltage:

[0038] SOC = 1 / C bat ·∫(Ich-Idis)dt+SOC0 (3)

[0039] Where SOC represents the state of charge of the battery, Cbat represents the rated capacity of the battery, the ampere-hours of the battery are obtained by integrating the difference between the charging and discharging currents, SOC0 is the initial value of the battery's state of charge at the start of the simulation analysis, and the functional relationship between the ampere-hours and the open-circuit voltage can be approximated by a linear function with coefficients k and b. The parameters k and b are fitted from the battery test data. The functional relationship between the ampere-hours and the open-circuit voltage is as follows:

[0040] Ebat=1 / k*(SOC-b) (4)

[0041] The battery pack terminal voltage Vbat consists of the open-circuit voltage Ebat and the voltage drop across the internal resistance Rbat;

[0042] Vbat=Ebat+(Ich-Idis)*Rbat (5)

[0043] Method for calculating the depth of discharge (DoD) of a battery:

[0044] DoD = 1 - SOC

[0045] During the constant-voltage charging process of a battery, once the battery voltage reaches the charging cutoff voltage, the charging current gradually decreases. At this point, the charging current Ich is...

[0046] Ich(N)=Ich(N-1)*e -1 / k / Rbat / Cbat / 3600*Ns*Step (6)

[0047] Where Ns is the number of battery cells in series, Step is the simulation step size, and N is the time series;

[0048] In Equations 1 to 6, Psa, Pload, η1, η2, SOC0, k, b, Rbat, Cbat, Ns, and Step are the values ​​input by the designer at the start of the simulation, and the other variables are intermediate values ​​during the simulation process.

[0049] Furthermore, in step S1, when establishing the power regulation and control unit (PCU) and the platform and load electrical equipment models,

[0050] The role of the PCU in controlling the charging and discharging current of the battery is reflected in equations (1) and (2). The load model is represented by the load power Pload in equations (1) and (2).

[0051] The beneficial effects of this invention are:

[0052] The energy balance analysis tool proposed in this invention has been practically applied in satellite power system design and has received positive feedback. Furthermore, comparison with on-orbit satellite data shows that the analysis and calculation results of the tool proposed in this invention have a high degree of matching accuracy with the on-orbit data, and the results are accurate and reliable. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the user interface of the software tool in an embodiment of the present invention;

[0054] Figure 2 This is a flowchart illustrating the method used in an embodiment of the present invention;

[0055] Figure 3 This is a typical output result of the method in the embodiments of the present invention;

[0056] Figure 4 This is a comparison chart of the method results and satellite data in the embodiments of the present invention. Detailed Implementation

[0057] To make the technical solutions and advantages of the present invention clearer, the technical solutions of the embodiments of the present invention will be fully described below with reference to the figures in the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0058] Embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the figures, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the figures are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0059] The satellite power system energy balance analysis tool proposed in this invention uses the Matlab programming language to establish electrical models of each device in the power subsystem, and accepts input data and outputs analysis and calculation results through a graphical user interface. It simulates the energy flow between devices in the power system through time-domain simulation, and calculates and analyzes the energy balance of energy storage devices over a period of time.

[0060] 1. Graphical User Interface

[0061] The user interface of the software tool proposed in this invention was drawn using the Matlab GUI tool, such as... Figure 1 As shown, this interface provides the interaction interface between the designer and the tool. The software interface is divided into four functional areas, numbered as follows: 1. Control control area, 2. Simulation mode selection and configuration input area, 3. Simulation waveform output area, and 4. Cursor value display area.

[0062] The control area contains controls for "Import External Input Data" and "Start Simulation". "Import External Input Data" imports external data required for the simulation analysis, such as power demand data of electrical equipment, into the analysis tool. "Start Simulation" initiates the tool's calculation process. Simulation can only begin after the software detects that all necessary input data is complete.

[0063] Simulation Mode Selection Area: This area allows users to set simulation conditions. These include the source of the solar array output power data (manual input or external import is possible), the simulation time step and duration, the simulation mode selection (daily simulation or yearly simulation), the start and end dates of the simulation period, and the solar array shading conditions. The definitions of simulation modes are shown in Table 1.

[0064] Table 1: Simulation Mode Selection Table

[0065]

[0066] Configuration Input Area: This area allows users to input design parameters for the power system, including the selection and configuration of the battery, PCU, and solar array. A detailed list of input parameters is shown in Table 2.

[0067] Table 2: Configuration Items Table

[0068]

[0069]

[0070] The waveform output area displays the analysis results, including waveforms of the solar array's output power and load power, the charging and discharging current waveforms of energy storage devices (taking batteries as an example), the depth of discharge waveforms of energy storage devices, and the voltage waveforms of energy storage devices. These waveforms allow for a direct assessment of whether the energy storage devices in the satellite power system are in balance.

[0071] The cursor value display area is used to display the values ​​of each variable at the specific moment selected by the cursor on the waveform.

[0072] 2. Model of solar cell array, battery, load, and PCU

[0073] 2.1 Solar Cell Array Model

[0074] Different simulation modes correspond to different sources of solar array output power data. In the "external import" mode, the solar array output power data is directly read from external data files by the analysis tool proposed in this invention.

[0075] In "single-day simulation" or "one-year simulation" modes, the power data is calculated by the analysis tool proposed in this invention using the solar array selection and configuration parameters, and based on the current Earth-Sun distance and the angle of sunlight incidence. The output power of the solar array during the sunshine period is equal to the product of the bus voltage and the output current of the solar array. The bus voltage is equal to the user-defined desired value.

[0076] Vm, Im, Voc, and Isc represent the voltage and current at the maximum power point, open-circuit voltage, and short-circuit current, respectively. These four parameters are determined by the area and material of the solar cells and are affected by factors such as temperature and light intensity. The four parameters Vm, Im, Voc, and Isc determine the shape of the VI curve of the solar array. The output current of the solar array is derived from points on the VI curve. For each bus voltage, a corresponding output current of the solar array can be obtained.

[0077] 2.2 Battery Model

[0078] Method for calculating the battery charging current Ich during the sunshine period:

[0079] Ich=(Psa-Pload)*η1 / Vbat (1)

[0080] Where Psa is the output power of the solar array, Pload is the load power, Vbat is the battery terminal voltage, and η1 is the PCU charging efficiency. The method for calculating the battery discharge current Idis during the shadow period is as follows:

[0081] Idis = Pload / η2 / Vbat (2)

[0082] Where η2 is the PCU discharge efficiency. The calculation method for battery pack voltage is as follows:

[0083] SOC = 1 / C bat ·∫(Ich-Idis)dt+SOC0 (3)

[0084] Where SOC represents the state of charge of the battery, Cbat represents the rated capacity of the battery, and the ampere-hours of the battery are obtained by integrating the difference between the charging and discharging currents. SOC0 is the initial value of the battery's state of charge at the start of the simulation analysis. The functional relationship between the ampere-hours and the open-circuit voltage (Equation 4) can be approximated by a linear function with coefficients k and b. Parameters k and b are obtained by fitting battery test data.

[0085] Ebat=1 / k*(SOC-b) (4)

[0086] The battery pack terminal voltage Vbat consists of the open-circuit voltage Ebat and the voltage drop across the internal resistance Rbat.

[0087] Vbat=Ebat+(Ich-Idis)*Rbat (5)

[0088] Method for calculating the depth of discharge (DoD) of a battery:

[0089] DoD = 1 - SOC

[0090] During the constant-voltage charging process of a battery, the charging current gradually decreases after the battery voltage reaches the charging cutoff voltage. At this point, the charging current Ich is...

[0091] Ich(N)=Ich(N-1)*e -1 / k / Rbat / Cbat / 3600*Ns*Step (6)

[0092] Where Ns is the number of battery cells in series, Step is the simulation step size (in seconds), and N is the time series.

[0093] In Equations 1 to 6, Psa, Pload, η1, η2, SOC0, k, b, Rbat, Cbat, Ns, and Step are the values ​​input by the designer at the start of the simulation, and the other variables are intermediate values ​​during the simulation process.

[0094] 2.3 PCU and Load Model

[0095] The role of the PCU in controlling the charging and discharging current of the battery is reflected in equations (1) and (2). The load model is represented by the load power Pload in equations (1) and (2).

[0096] 3. Simulation and Analysis Process of Tools

[0097] The flowchart of the energy balance analysis tool proposed in this invention is as follows: Figure 2 As shown.

[0098] First, select the desired simulation analysis mode, which includes three modes: "External Import Simulation," "Daily Simulation," and "Annual Simulation." The differences between the three modes are shown in Table 1.

[0099] In the "External Import Simulation" mode, both solar array power data and load power data are read from external data files, and the simulation duration depends on the time step and data length. In the other two modes, the simulation durations are 24 hours and one year, respectively, with only load power data read from external data files. The time step for all three modes is determined by the designer based on the data file format, ranging from 1 second to 1 hour.

[0100] In the "Single-Day Simulation" mode, designers can choose whether to consider solar panel shading as needed. If so, the tool allows setting the shading coefficient and shading time. During the shading period, the solar panel's output power will be reduced according to the coefficient. In Single-Day Simulation mode, the ground shadow time can be customized; during the ground shadow period, the solar panel's output power will be set to 0.

[0101] In the "One-Year Simulation Mode," the tool will automatically set the ground shadow based on the geostationary orbit's shadow characteristics: the longest shadow is on the spring and autumn equinoxes (72 minutes), and the shadows in spring and autumn each last 45 days, gradually increasing and then decreasing within those 45 days. This mode does not consider occlusion.

[0102] Secondly, according to the power system design scheme, input the actual hardware configuration parameters of the battery, PCU, and solar array (excluding "external import simulation") into the corresponding locations on the user interface. The parameters that need to be input are shown in Table 2.

[0103] Finally, read the external data file, including the solar array output power (only required under "External Import Simulation") and load demand power data. After successful import, the tool can begin simulation analysis.

[0104] 4. Tool Output Results

[0105] A typical output of the energy balance analysis tool proposed in this invention is as follows: Figure 3 As shown in the figure, this figure corresponds to the simulation analysis results of a certain "one-year simulation" mode.

[0106] Figure 3 The curves output by the tool correspond to the following variables: solar array output power and load demand power, battery charging and discharging current, battery depth of discharge (DoD), and voltage. The curves show how each variable changes over time. If the battery depth of discharge never exceeds the threshold, the power system design is considered to meet the energy balance requirements.

[0107] In addition, the tool can automatically count the number of times the battery has been discharged and the maximum depth of discharge.

[0108] To verify the tool's correctness and calculation accuracy, on-orbit data from a satellite was compared with the software's calculation results. Telemetry data on the satellite's on-orbit solar array output power and load power were imported into the tool via an external data file in "external import" mode. The configuration parameters for the satellite were then input into the user interface according to its actual hardware configuration. Curves for the main variables calculated by the energy balance analysis tool were compared with the curves from the on-orbit data. The results are as follows: Figure 4 As shown in the figure. Statistical calculations show that the root mean square error of each variable is less than 3%, indicating that the simulation analysis results of the tool are highly accurate and have a good agreement with the on-orbit data.

[0109] In the description of this specification, references to terms such as "an embodiment" and "example" refer to specific features, structures, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms are not necessarily intended to refer to corresponding embodiments or examples in a suitable manner.

[0110] It must be pointed out that the above description of the embodiments is not intended to limit the invention but only to help understand the core idea of ​​the invention. For those skilled in the art, any improvements to the invention and equivalent alternatives made to the invention without departing from the principle of the invention are also within the scope of protection of the claims of the invention.

Claims

1. A method for energy balance analysis of a satellite power system, characterized in that, Includes the following steps: S1: Based on Matlab, models of solar cell array, battery, power regulation and control unit (PCU), platform and payload electrical equipment are established to simulate the energy flow process of the satellite power system; In step S1, when establishing the battery model, The method for calculating the battery charging current Ich during the sunshine period is as follows: Ich = (Psa – Pload)* ŋ1 / Vbat (1) Where Psa is the output power of the solar cell array, Pload is the load power, Vbat is the battery terminal voltage, and ŋ1 is the PCU charging efficiency. Method for calculating the battery discharge current Idis during the shadow period: Idis = Pload / ŋ2 / Vbat (2) Where ŋ2 is the PCU discharge efficiency; Methods for calculating the state of charge of a battery pack: (3) Where SOC represents the state of charge of the battery, and Cbat represents the rated capacity of the battery; the ampere-hours of the battery are obtained by integrating the difference between the charging and discharging currents, and SOC0 is the initial value of the battery's state of charge at the start of the simulation analysis. The functional relationship between the ampere-hours and the open-circuit voltage can be approximated by a linear function with coefficients k and b. The parameters k and b are obtained by fitting the battery test data. The functional relationship between the ampere-hours and the open-circuit voltage is as follows: Ebat = 1 / k * (SOC – b) (4) The battery pack terminal voltage Vbat consists of the open-circuit voltage Ebat and the voltage drop across the internal resistance Rbat; Vbat = Ebat + (Ich-Idis)*Rbat (5) Method for calculating the depth of discharge (DoD) of a battery: DoD = 1-SOC During the constant-voltage charging process of a battery, once the battery voltage reaches the charging cutoff voltage, the charging current gradually decreases. At this point, the charging current Ich is... I(N) = I(N-1)*e -1 / k / Rbat / Cbat / 3600*Ns*Step (6) Where Ns is the number of battery cells in series, Step is the simulation step size, and N is the time series; In Equations 1 to 6, Psa, Pload, ŋ1, ŋ2, SOC0, k, b, Rbat, Cbat, Ns, and Step are the values ​​input by the designer at the start of the simulation, and the other variables are intermediate values ​​during the simulation process. S2: Develop a graphical user interface using Matlab GUI to provide an interactive interface for satellite power system energy balance analysis tools and power system designers; S3: The designer inputs the current power system design scheme and the power demand data of the electrical equipment through the interactive interface of the graphical user interface; S4: Based on the data input in step S3, analyze and judge the energy balance of the satellite energy storage device over a certain period of time by simulating the energy flow state, and give the energy balance analysis curve and conclusion.

2. The method according to claim 1, characterized in that, In step S1, The solar cell array model includes parameters such as the number of arrays, cell efficiency, size, and number of series and parallel connections; The battery model includes parameters such as individual cell capacity, number of series and parallel connections, and capacity decay rate. The power regulation and control unit model includes battery charging and discharging management and protection logic, as well as different bus systems, including bus regulation methods and operating efficiency parameters of the charging and discharging units; The platform and load power equipment models include load power and power distribution loss parameters.

3. The method according to claim 1, characterized in that, In step S3, the user inputs the design parameters of the power system, including the selection and configuration of the battery, PCU, and solar array. Battery parameters include: number of battery packs, cell type, internal resistance of battery pack, number of cells connected in series, series-parallel connection, whether battery failure is considered, initial state of charge of the battery at the start of the simulation, nominal capacity of a single pack, factory test capacity of a single pack, capacity decay rate, self-discharge coefficient, and state of charge range during the sunlight season. PCU parameters include: bus regulation system, BCR efficiency, BDR efficiency, constant current charging level during the solar season, and constant current charging level during the shadow season. Solar cell array parameters include: number of cell strings, whether cell failure is considered, degradation rate, number of subarrays, number of parallel arrays per array, cell type, and cell size.

4. The method according to claim 1, characterized in that, In step S4, the conclusions include waveforms that display the analysis results, including waveforms of the output power and load power of the solar cell array, waveforms of the charging and discharging current of the energy storage device, waveforms of the discharge depth of the energy storage device, and waveforms of the voltage of the energy storage device. These waveforms allow for a direct assessment of whether the energy of the energy storage device in the satellite power system is balanced.

5. The method according to claim 4, characterized in that, The energy storage device is a battery.

6. The method according to claim 1, characterized in that, Before step S1, the following steps are also included: selecting a simulation analysis mode, which includes three modes: external import simulation, daily simulation, and annual simulation.

7. The method according to claim 6, characterized in that, In external import mode, both solar array power data and load power data are read from external data files, and the simulation time depends on the time step and data length. In the other two modes, the simulation time is 24 hours and one year, respectively, and only the load power data is read from external data files. The time step for all three modes is determined by the designer according to the format of the data file, ranging from 1 second to 1 hour. In single-day simulation mode, designers can choose whether to consider solar panel shading as needed. If so, the tool can set the shading coefficient and shading time. During the shading period, the solar panel output power will be reduced by the coefficient. In single-day simulation mode, the ground shadow time can be customized. During the ground shadow time period, the output power of the solar array will be set to 0. In the one-year simulation mode, the tool will automatically set the ground shadow situation based on the geostationary orbit shadow situation, that is, the ground shadow is the longest on the spring and autumn equinoxes, with a length of 72 minutes, and the ground shadow length is 45 days in spring and autumn, and the length of the ground shadow is gradually increasing and then gradually decreasing within 45 days; this mode does not consider occlusion.

8. The method according to claim 6, characterized in that, In step S1, when establishing the solar cell array model, In external import mode, the output power data of the solar cell array is read directly from an external data file; In single-day or year-long simulation modes, the output power data of the solar array is calculated based on the solar array selection and configuration parameters, and according to the current Earth-Sun distance and solar incidence angle. During the illumination period, the output power of the solar array is equal to the product of the bus voltage and the output current. The bus voltage is equal to the user-defined desired value. Vm, Im, Voc, and Isc represent the voltage, current, open-circuit voltage, and short-circuit current at the maximum power point, respectively. These four parameters are determined by the area and material of the solar cells and are affected by temperature, light intensity, etc. The four parameters Vm, Im, Voc, and Isc determine the shape of the solar array's VI curve. The output current of the solar array is derived from points on the VI curve. For each bus voltage, a corresponding solar array output current can be obtained.

9. The method according to claim 1, characterized in that, In step S1, when establishing the power regulation and control unit (PCU) and the platform and load electrical equipment models, The role of the PCU in controlling the charging and discharging current of the battery is reflected in equations (1) and (2), and the load model is reflected by the load power Pload in equations (1) and (2).

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