Autonomous yaw planning method based on yaw angle terminator optimization calculation

Abstract

The invention relates to an autonomous yaw planning method based on yaw angle terminator optimization calculation, provides a method for improving a satellite heat dissipation condition by rotating a satellite yaw angle by taking minimum heat flow integral of a south plate and a north plate in each orbit period of a satellite as a constraint condition, and designs a method for calculating a yaw rotation morning angle and a yaw rotation dusk angle according to the thought. Constraint conditions of calculation capability, period and memory capacity of a spaceborne computer are considered, links related to complex operation in the yaw terminator angle calculation method are properly simplified by adopting an approximate expression, and calculation efficiency and memory space occupation are improved. According to the invention, the requirements of small heat dissipation area and high heat dissipation power consumption of a remote satellite under the condition of an existing spaceborne computer are met.

Description

Technical Field

[0001] The invention belongs to the field of spacecraft guidance, navigation and control, and relates to a control method for autonomous satellite yaw planning. Background Art

[0002] Remote sensing satellite cameras generally require that sunlight cannot directly or indirectly enter the camera mirror. Structurally, satellites are designed with sunshades to block sunlight. The orbit of high-orbit remote sensing satellites determines that the positions of the sun and satellites will change with the revolution of the sun and the rotation of the earth. In order to achieve the sunshade to block sunlight in real time, the satellite's attitude must also change accordingly.

[0003] Existing high-orbit remote sensing satellites all fly upright (yaw angle is 0°) from 0:00 to 12:00 local time, perform yaw attitude maneuvers of 180° around 12:00 local time, and fly inverted (yaw angle 180°) from 12:00 to 24:00 local time. Since the power consumption of existing remote sensing satellites is not large, the current remote sensing satellite structure design is sufficient to meet the existing satellite heat dissipation conditions, so the existing technology does not consider the heat flux of sunlight on the satellite heat dissipation surface.

[0004] The remote sensing satellite has both remote sensing payload and communication payload, and the communication payload consumes a lot of power, so the overall power consumption of the satellite is greatly increased compared with traditional remote sensing satellites. However, the satellite structure still adopts the traditional remote sensing satellite structure design, which is smaller than the heat dissipation surface of traditional communication satellites, so the whole satellite has higher requirements for satellite heat dissipation. Therefore, under this condition, a method is needed to improve the heat dissipation of the satellite or reduce the heat accumulation on the heat dissipation surface. Summary of the invention

[0005] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art and to provide an autonomous yaw planning method based on the optimization calculation of the morning and evening values ​​of the yaw angle. The morning value and the evening value of the yaw angle of the satellite rotation can be calculated by the method. The yaw angle is controlled to be maintained at the morning value from 0:00 to 12:00 local time, and the yaw angle is controlled to be maintained at the evening value from 12:00 to 24:00 local time, thereby solving the problem of satellite heat dissipation.

[0006] The technical solution of the present invention is: an autonomous yaw planning method based on the optimization calculation of the yaw angle morning and evening values, comprising:

[0007] Define the morning and evening values ​​of the yaw angle;

[0008] According to the minimum requirement of the cumulative amount of solar radiation projection on the whole satellite heat dissipation surface, that is, the minimum integral value of the projection of the solar unit vector on the north and south plates, the solar projection integral model of the orbital period satellite heat dissipation surface is established;

[0009] According to the morning value and evening value of the yaw angle, the established orbital period satellite heat dissipation surface solar projection integral model is split to obtain the heat flow integral model A based on the morning value and the heat flow integral model B based on the evening value.

[0010] Calculate the morning value Ψ`morning and evening value Ψ`evening of the fixed yaw angle in the heat flux integral model A based on the morning value and the heat flux integral model B based on the evening value;

[0011] According to the obtained fixed yaw angle morning value Ψ`morning and evening value Ψ`evening, the autonomous yaw planning method is determined.

[0012] The definition of the morning value Ψmorning and the evening value Ψevening of the yaw angle includes:

[0013] The satellite maintains a fixed yaw angle in each orbital period, and two reference values ​​are set for the fixed yaw angle, namely:

[0014] Morning value Ψmorning: The planned yaw angle of the satellite from 0:00 to 12:00 local time, ranging from 0° to 90°;

[0015] Evening value Ψevening: The yaw angle of the satellite planned from 12:00 to 24:00 local time, ranging from 90° to 180°.

[0016] The specific steps of establishing the orbital period satellite heat dissipation surface solar projection integral model are as follows:

[0017]

[0018] Where J represents the solar projection integral of the satellite heat dissipation surface in one orbital period, β S is the angle between the sun vector and the XOZ plane of the satellite body, S x , S y , S z is the solar vector in the southeast system, R z (ψ * ), R y (θ) are based on ψ * , The direction cosine matrix of the θ rotation, ψ * , θ represents the yaw angle, pitch angle, and roll angle based on the 312 rotation sequence of the Southeast system; minJ in the model represents the reasonable selection of ψ * , The three values ​​of θ minimize the solar projection integral of the satellite's heat dissipation surface in one orbital period.

[0019] The heat flow integral model A based on the morning value is expressed by selecting ψ * , The three values ​​of θ allow the satellite to accumulate min J from 0:00 to 12:00 local time; that is:

[0020]

[0021] The heat flow integral model B based on the dim value is expressed by selecting ψ * , The three values ​​of θ allow the satellite to accumulate min J from 12:00 to 24:00 local time; that is:

[0022]

[0023] The solar vector S in the southeast system x , S y , S z Specifically:

[0024] S x =cosδ s sinα

[0025] S y = -sinδ s cosΔρ-cosδ s cosαsinΔρ

[0026] S z = -sinδ s sinΔρ+cosδ s cosαcosΔρ

[0027] where δ s is the solar declination, α is the current local hour angle of the satellite, and Δρ is the latitude drift of the satellite's sub-satellite position.

[0028] The R z (ψ * ), R y The calculation method of (θ) is as follows:

[0029] Establish θ and ψ * Relationship model;

[0030]

[0031] θ=arcsin(T x cosψ+T y sinψ)

[0032] ψ=ψ *

[0033] Where (T x ,Ty ,T z ) is the unit target pointing vector in the southeast system; according to θ and ψ * R z (ψ * ), R y (θ).

[0034] The unit target pointing vector (T x ,T y ,T z ) is calculated as follows:

[0035]

[0036]

[0037] Among them, (P x ,P y ,P z ) is the target position vector in the southeast system, (A, B) is the target longitude and latitude, λ0 is the satellite fixed point longitude, R e is the radius of the Earth, R s is the synchronous orbit radius, is the latitude drift.

[0038] The calculation of the fixed yaw angle morning value Ψ`morning and evening value Ψ`evening in the heat flow integral model A based on the morning value and the heat flow integral model B based on the evening value includes:

[0039] Given the initial yaw angle value Ψm n , determine the corresponding parameter K n ; The parameter K n Including the unit target pointing vector, sun position vector, and three-axis attitude angle in the satellite southeast system; the heat flux J is calculated according to the heat flux integral model A based on the morning value n ; n = 1.2 ... N; wherein N is a uniformly spaced fraction from 0:00 to 12:00 local time; in J n Find min J in the equation; since min J has only one minimum point within the yaw angle range of 0° to 90°, the Ψm corresponding to min J is n As the optimal morning value of the yaw angle obtained by iteration, Ψ`morning;

[0040] Given the initial yaw angle value Ψe n , determine the corresponding parameter K` n ; The parameter K` nIncluding the unit target pointing vector, sun position vector, and three-axis attitude angle in the satellite southeast system; the heat flux J is calculated based on the heat flux integral model B based on the dusk value. n ; n = 1.2 ... N; where N is a uniformly spaced fraction from 0:00 to 12:00 local time; in J` n Find min J` in the equation; since min J` has only one minimum point within the yaw angle range of 90° to 180°, the Ψe corresponding to min J` is n As the optimal yaw angle evening value Ψ`evening obtained by iteration.

[0041] According to the obtained fixed yaw angle morning value Ψ`morning and evening value Ψ`evening, the autonomous yaw planning method is determined, including:

[0042] The satellite controls the yaw angle to maintain the morning value Ψ`morning from 0:00 to 12:00 local time, and performs a yaw attitude maneuver around 12:00 local time, with the yaw angle maneuvering from the morning value Ψ`morning to the dusk value Ψ`evening. From 12:00 to 24:00 local time, the satellite controls the yaw angle to maintain the dusk value Ψ`evening; and performs a yaw attitude maneuver around 00:00 local time, with the yaw angle maneuvering from the dusk value Ψ`evening to the morning value Ψ`morning.

[0043] Compared with the prior art, the advantages of the present invention are as follows: the existing remote sensing satellite yaw control method only considers that sunlight cannot directly or indirectly enter the camera mirror during the control process, and does not consider the heat dissipation problem of the satellite. In view of the heat dissipation problem of remote sensing satellites and the current status of yaw planning and control, the present invention proposes an autonomous yaw planning method based on the optimization calculation of the yaw angle morning and evening values. This method is based on the solar cumulative minimum optimization index function, and through algorithm optimization, the optimal yaw rotation angle is recursively calculated, so as to achieve the minimum cumulative heat flux of the satellite heat dissipation surface through yaw rotation control per orbital cycle, thereby improving the satellite heat dissipation conditions. For the solar vector and target vector calculation method used in this method, the links involving complex calculations are appropriately optimized using approximate expressions to reduce the amount of calculation and simplify the process. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a flowchart of the method of the present invention. DETAILED DESCRIPTION

[0045] The present invention provides an autonomous yaw planning method based on optimization calculation of yaw angle morning and evening values, comprising:

[0046] Define the morning and evening values ​​of the yaw angle;

[0047] According to the minimum requirement of the cumulative amount of solar radiation projection on the whole satellite heat dissipation surface, that is, the minimum integral value of the projection of the solar unit vector on the north and south plates, the solar projection integral model of the orbital period satellite heat dissipation surface is established;

[0048] According to the morning value and evening value of the yaw angle, the established orbital period satellite heat dissipation surface solar projection integral model is split to obtain the heat flow integral model A based on the morning value and the heat flow integral model B based on the evening value.

[0049] Calculate the morning value Ψ`morning and evening value Ψ`evening of the fixed yaw angle in the heat flux integral model A based on the morning value and the heat flux integral model B based on the evening value;

[0050] According to the obtained fixed yaw angle morning value Ψ`morning and evening value Ψ`evening, the autonomous yaw planning method is determined.

[0051] The definition of the morning value Ψmorning and the evening value Ψevening of the yaw angle includes:

[0052] The satellite maintains a fixed yaw angle in each orbital period, and two reference values ​​are set for the fixed yaw angle, namely:

[0053] Morning value Ψmorning: The planned yaw angle of the satellite from 0:00 to 12:00 local time, ranging from 0° to 90°;

[0054] Evening value Ψevening: The yaw angle of the satellite planned from 12:00 to 24:00 local time, ranging from 90° to 180°.

[0055] The specific steps of establishing the orbital period satellite heat dissipation surface solar projection integral model are as follows:

[0056]

[0057] Where J represents the solar projection integral of the satellite heat dissipation surface in one orbital period, β S is the angle between the sun vector and the XOZ plane of the satellite body, S x , S y , S z is the solar vector in the southeast system, R z (ψ * ), R y (θ) are based on ψ * , The direction cosine matrix of the θ rotation, ψ * , θ represents the yaw angle, pitch angle, and roll angle based on the 312 rotation sequence of the Southeast system; minJ in the model represents the reasonable selection of ψ * , The three values ​​of θ minimize the solar projection integral of the satellite's heat dissipation surface in one orbital period.

[0058] The heat flow integral model A based on the morning value is expressed by selecting ψ * , The three values ​​of θ allow the satellite to accumulate min J from 0:00 to 12:00 local time; that is:

[0059]

[0060] The heat flow integral model B based on the dim value is expressed by selecting ψ * , The three values ​​of θ allow the satellite to accumulate min J from 12:00 to 24:00 local time; that is:

[0061]

[0062] The solar vector S in the southeast system x , S y , S z Specifically:

[0063] S x =cosδ s sinα

[0064] S y = -sinδ s cosΔρ-cosδ s cosαsinΔρ

[0065] S z = -sinδ s sinΔρ+cosδ s cosαcosΔρ

[0066] where δ s is the solar declination, α is the current local hour angle of the satellite, and Δρ is the latitude drift of the satellite's sub-satellite position.

[0067] The R z (ψ * ), R y The calculation method of (θ) is as follows:

[0068] Establish θ and ψ * Relationship model;

[0069]

[0070] θ=arcsin(T x cosψ+T y sinψ)

[0071] ψ=ψ *

[0072] Where (T x ,T y ,T z ) is the unit target pointing vector in the southeast system; according to θ and ψ * R z (ψ * ), R y (θ).

[0073] The unit target pointing vector (T x ,T y ,T z ) is calculated as follows:

[0074]

[0075]

[0076] Among them, (P x ,P y ,P z ) is the target position vector in the southeast system, (A, B) is the target longitude and latitude, λ0 is the satellite fixed point longitude, R e is the radius of the Earth, R s is the synchronous orbit radius, is the latitude drift.

[0077] The calculation of the fixed yaw angle morning value Ψ`morning and evening value Ψ`evening in the heat flow integral model A based on the morning value and the heat flow integral model B based on the evening value includes:

[0078] Given the initial yaw angle value Ψm n , determine the corresponding parameter K n ; The parameter K n Including the unit target pointing vector, sun position vector, and three-axis attitude angle in the satellite southeast system; the heat flux J is calculated according to the heat flux integral model A based on the morning value n ; n = 1.2 ... N; wherein N is a uniformly spaced fraction from 0:00 to 12:00 local time; in J n Find min J in the equation; since min J has only one minimum point within the yaw angle range of 0° to 90°, the Ψm corresponding to min J is n As the optimal morning value of the yaw angle obtained by iteration, Ψ`morning;

[0079] Given the initial yaw angle value Ψe n, determine the corresponding parameter K` n ; The parameter K` n Including the unit target pointing vector, sun position vector, and three-axis attitude angle in the satellite southeast system; the heat flux J is calculated based on the heat flux integral model B based on the dusk value. n ; n = 1.2 ... N; where N is a uniformly spaced fraction from 0:00 to 12:00 local time; in J` n Find min J` in the equation; since min J` has only one minimum point within the yaw angle range of 90° to 180°, the Ψe corresponding to min J` is n As the optimal yaw angle evening value Ψ`evening obtained by iteration.

[0080] According to the obtained fixed yaw angle morning value Ψ`morning and evening value Ψ`evening, the autonomous yaw planning method is determined, including:

[0081] The satellite controls the yaw angle to maintain the morning value Ψ`morning from 0:00 to 12:00 local time, and performs a yaw attitude maneuver around 12:00 local time, with the yaw angle maneuvering from the morning value Ψ`morning to the dusk value Ψ`evening. From 12:00 to 24:00 local time, the satellite controls the yaw angle to maintain the dusk value Ψ`evening; and performs a yaw attitude maneuver around 00:00 local time, with the yaw angle maneuvering from the dusk value Ψ`evening to the morning value Ψ`morning.

[0082] like Figure 1 As shown, it is a flowchart of an embodiment of the method of the present invention, and the main steps are as follows:

[0083] (1) Real-time calculation of the satellite's current local time angle and the latitude drift of the sub-satellite position

[0084] First, define the satellite local time angle: the phase of the satellite projection in the equatorial plane relative to the sun: 0:00 (0°) corresponds to a phase difference of 180° between the satellite and the sun, 6:00 corresponds to a phase difference of 90° between the satellite and the sun, 12:00 (180°) corresponds to the same phase as the satellite and the sun, and 18:00 corresponds to a phase difference of 270° between the satellite and the sun. The satellite is in a synchronous orbit, and the local time angle increases evenly over time.

[0085] The local hour angle of the satellite passing the ascending node:

[0086] α G =Ω+π-λ S (a)

[0087] Where Ω is the right ascension of the satellite ascending node, λ S It is the solar right ascension.

[0088] Due to the orbital inclination, the satellite sub-satellite position drift Δλ (longitude) and Δρ (latitude) is:

[0089]

[0090] Δρ=i sin(α-α G ) (c)

[0091] α is the current local hour angle of the satellite, and i is the inclination of the satellite orbit.

[0092] It can be seen from equations (b) and (c) that when the satellite is operating at a small inclination angle of 5°, the daily longitude drift of the satellite's sub-satellite point is much smaller than the latitude drift. Therefore, the small changes in the satellite's longitude are ignored, and it is approximately assumed that the satellite only moves in the north-south direction on the longitude line where the fixed position is located.

[0093] (2) According to the analysis in step 1, the calculation of the solar vector in the southeast system is simplified, and the calculation formula of the solar position vector in the southeast system can be obtained, where δ s is the solar declination.

[0094] S x =cosδ s sinα

[0095] S y = -sinδ s cosΔρ-cosδ s cosαsinΔρ

[0096] S z = -sinδ s sinΔρ+cosδ s cosαcosΔρ(d)

[0097] (3) Calculate the target position vector in the southeast system, where (P x ,P y ,P z ) is the target position vector in the southeast system, (A, B) is the target longitude and latitude, λ0 is the satellite fixed point longitude, R e is the radius of the Earth, R s is the synchronous orbit radius, is the latitude drift.

[0098]

[0099]

[0100] (4) Given the initial value of the yaw angle Ψ0, calculate the three-axis attitude angle (Southeast system 312 rotation sequence).

[0101]

[0102] θ=arcsin(T x cosψ+T y sinψ)

[0103] ψ=ψ * (f)

[0104] (5) Based on θ and ψ * R z (ψ * ), R y (θ).

[0105] (6) Heat flux integration model A based on morning values ​​and heat flux integration model B based on evening values ​​are used to calculate the cumulative heat flux of the satellite per orbital period.

[0106] Model A:

[0107]

[0108] Model B:

[0109]

[0110] (6) Based on steps 1 to 6, the morning and evening values ​​of the yaw angle are iteratively optimized. Since the morning value of the yaw angle has only one minimum point in the range of 0° to 90° (the evening value is in the range of 90° to 180°), the optimal morning value of the yaw angle Ψ`morning and the optimal evening value of the yaw angle Ψ`evening can be iteratively obtained.

[0111] (7) Determine an autonomous yaw planning method based on the obtained fixed yaw angle morning value Ψ`morning and evening value Ψ`evening, including:

[0112] The satellite controls the yaw angle to maintain the morning value Ψ`morning from 0:00 to 12:00, performs yaw attitude maneuvers around 12:00 local time, and the yaw angle maneuvers from the morning value Ψ`morning to the dusk value Ψ`evening. From 12:00 to 24:00 local time, the satellite controls the yaw angle to maintain the dusk value Ψ`evening; around 00:00 local time, performs yaw attitude maneuvers, and the yaw angle maneuvers from the dusk value Ψ`evening to the morning value Ψ`morning.

[0113] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. An autonomous yaw planning method based on optimization calculation of yaw angle morning and evening values, characterized in that: include: Define the morning and evening values ​​of the yaw angle; According to the minimum requirement of the cumulative amount of solar radiation projection on the whole satellite heat dissipation surface, that is, the minimum integral value of the projection of the solar unit vector on the north and south plates, the solar projection integral model of the orbital period satellite heat dissipation surface is established; According to the morning value and evening value of the yaw angle, the established orbital period satellite heat dissipation surface solar projection integral model is split to obtain the heat flow integral model A based on the morning value and the heat flow integral model B based on the evening value. Calculate the morning value Ψ`morning and evening value Ψ`evening of the fixed yaw angle in the heat flux integral model A based on the morning value and the heat flux integral model B based on the evening value; According to the obtained fixed yaw angle morning value Ψ`morning and evening value Ψ`evening, the autonomous yaw planning method is determined.

2. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 1 is characterized in that: The definition of the morning value Ψmorning and the evening value Ψevening of the yaw angle includes: The satellite maintains a fixed yaw angle in each orbital period, and two reference values ​​are set for the fixed yaw angle, namely: Morning value Ψmorning: The planned yaw angle of the satellite from 0:00 to 12:00 local time, ranging from 0° to 90°; Evening value Ψevening: The yaw angle of the satellite planned from 12:00 to 24:00 local time, ranging from 90° to 180°.

3. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 1, characterized in that: The specific steps of establishing the orbital period satellite heat dissipation surface solar projection integral model are as follows: Where J represents the solar projection integral of the satellite heat dissipation surface in one orbital period, β S is the angle between the sun vector and the XOZ plane of the satellite body, S x , S y , S z is the solar vector in the southeast system, R z (ψ * ), R y (θ) are based on ψ * , The direction cosine matrix of the θ rotation, ψ * , θ represents the yaw angle, pitch angle, and roll angle based on the 312 rotation sequence of the Southeast system; minJ in the model represents the reasonable selection of ψ * , The three values ​​of θ minimize the solar projection integral of the satellite's heat dissipation surface in one orbital period.

4. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 3 is characterized in that: The heat flow integral model A based on the morning value is expressed by selecting ψ * , The three values ​​of θ allow the satellite to accumulate minJ from 0:00 to 12:00 local time; that is:

5. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 3 is characterized in that: The heat flow integral model B based on the dim value is expressed by selecting ψ * , The three values ​​of θ allow the satellite to accumulate minJ from 12:00 to 24:00 local time; that is:

6. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 3 is characterized in that: The solar vector S in the southeast system x , S y , S z Specifically: S x =cosδ s Sinai S y =-sinδ s cosΔρ-cosδ s cosαsinΔρ S z =-sinδ s sinΔρ+cosδ s cosαcosΔρ where δ s is the solar declination, α is the current local hour angle of the satellite, and Δρ is the latitude drift of the satellite's sub-satellite position.

7. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 1, characterized in that: The R z (ψ * ), R y The calculation method of (θ) is as follows: Establish θ and ψ * Relationship model; θ=arcsin(T x cosψ+T y sinψ) ψ=ψ * Where (T x ,T y ,T z ) is the unit target pointing vector in the southeast system; according to θ and ψ * R z (ψ * ), R y (θ).

8. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 7, characterized in that: The unit target pointing vector (T x ,T y ,T z ) is calculated as follows: Among them, (P x ,P y ,P z ) is the target position vector in the southeast system, (A, B) is the target longitude and latitude, λ0 is the satellite fixed point longitude, R e is the radius of the Earth, R s is the synchronous orbit radius, is the latitude drift.

9. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 4, characterized in that: The calculation of the fixed yaw angle morning value Ψ`morning and evening value Ψ`evening in the heat flow integral model A based on the morning value and the heat flow integral model B based on the evening value includes: Given the initial yaw angle value Ψm n , determine the corresponding parameter K n ; The parameter K n Including the unit target pointing vector, sun position vector, and three-axis attitude angle in the satellite southeast system; the heat flux J is calculated according to the heat flux integral model A based on the morning value n ; n = 1.2 ... N; wherein N is a uniformly spaced fraction from 0:00 to 12:00 local time; in J n Find minJ from the equation; since minJ has only one minimum point within the yaw angle range of 0° to 90°, the Ψm corresponding to minJ is n As the optimal morning value of the yaw angle obtained by iteration, Ψ`morning; Given the initial yaw angle value Ψe n , determine the corresponding parameter K` n ; The parameter K` n Including the unit target pointing vector, sun position vector, and three-axis attitude angle in the satellite southeast system; the heat flux J is calculated based on the heat flux integral model B based on the dusk value. n ; n = 1.2 ... N; where N is a uniformly spaced fraction from 0:00 to 12:00 local time; in J` n Find minJ` in the equation; since minJ` has only one minimum point within the yaw angle range of 90° to 180°, the Ψe corresponding to minJ` is n As the optimal yaw angle evening value Ψ`evening obtained by iteration.

10. The autonomous yaw planning method based on the optimization calculation of the yaw angle dawn and dusk value according to claim 1, characterized in that: According to the obtained fixed yaw angle morning value Ψ`morning and evening value Ψ`evening, the autonomous yaw planning method is determined, including: The satellite controls the yaw angle to maintain the morning value Ψ`morning from 0:00 to 12:00 local time, and performs a yaw attitude maneuver around 12:00 local time, with the yaw angle maneuvering from the morning value Ψ`morning to the dusk value Ψ`evening. From 12:00 to 24:00 local time, the satellite controls the yaw angle to maintain the dusk value Ψ`evening; and performs a yaw attitude maneuver around 00:00 local time, with the yaw angle maneuvering from the dusk value Ψ`evening to the morning value Ψ`morning.

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