No-gyroscope sun capture control method of high orbit satellite large initial angular rate condition

Abstract

Disclosed is a no-gyroscope sun capture control method of a high orbit satellite large initial angular rate condition. After a satellite separates from a rocket, or before a normal control process enters the sun capture, a satellite independently enters a no-gyroscope sun capture mode if conditions are met. The method includes that firstly, rate damping is conducted; during the visible time of the sun in the sun sensor field, negative feedback satellite attitude control is conducted, accordingly, the X axis attitude and the Y axis attitude output and measured by the sun sensor are controlled towards the 0 degree direction, and -Z axis of the satellite is controlled to point to the sun direction; during the invisible time of the sun in the sun sensor field, corresponding thruster pulse width delta t i is utilized for compensating the angular rate of a control satellite. After the rate damping completes or achieves 360 s, if the sun is not in the sun sensor field of the -Z side, sun searching is begun; once the sun appears in two sun sensors on the -Z side and after signals are output for 2.048 s, the sensors switch into a cruising mode. After the cruising, X axis and Y axis attitude feedback signals maintain to be 0 during the earth shadow.

Description

technical field [0001] The invention relates to a control method under the condition of multiple faults of satellite gyroscopes. Background technique [0002] The sun acquisition modes of high-orbit satellites are divided into four modes: rate damping, pitching search, rolling search and cruise. The sun capture mode is used as a safety mode. Under normal circumstances, it is activated by the program-controlled command of the satellite attitude and orbit control system (AOCE) after the separation of the satellite and the rocket. After the transfer orbit satellite changes its orbit and is about to leave the country, it can enter the cruise by remote control on the ground. When a hardware failure alarm occurs in the transfer orbit control system, or when the synchronous orbit hardware failure alarm enters the hardware failure alarm and the earth pointing safety mode (ESM) is found within 40 minutes After reaching the earth, the on-board computer (OBC) of the control system can...

AI Technical Summary

Problems solved by technology

[0004] When one or more of the four gyroscopes fails and none of the gyroscopes on the star is marked with a health word, the balance equation of the angular rate measurement values ​​of the four gyroscopes cannot be satisfied. Gyro control mode

When the star and arrow separate, ω X , ω Y , ω Z , ω S When one or more actual values ​​exceed the saturation value (eg ±1° / s), ω X , ω Y , ω Z , ω S If one or more of the output values ​​are saturation values, the four gyro angular rate measurement values ​​cannot satisfy the balance equation. Because there is no process data for on-board independent identification, it is difficult to determine whether it is a gyro failure or a separation of the satellite and rocket caused by the launch. The three-axis angular velocity is greatly out of tolerance, so it is impossible to continue to use the gyro control mode

At this time, it is not possible to simply set the angular rate offset value to establish or eliminate the pitch search and roll search angular rates, and the rate damping closed-loop control cannot be performed, which may lead to loss of satellite attitude control. If the sun capture cannot be achieved for a long time, the The time is powered by the battery on the star. Once the power supply capacity of the battery is exceeded, the battery will be damaged, and the energy system on the star will not be able to supply power, which will cause the satellite to fail.

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