A Sinusoidal Yaw Control Mode for Inclined-Orbit Satellite

A proper yaw control mode is very important for an inclined-orbit satellite because of the complexity of the energy and thermal control, which is caused by the large range of the sun elevation angle variation. To get an accurate sun-pointing of solar panels, the ideal yaw attitude planning for sun-tracking is analyzed first. To avoid the excessive ideal yaw angular velocity, which is unavoidable for the ideal yaw attitude planning when the sun elevation angle nears to zero, a sinusoidal model for yaw attitude control is proposed without any singular value of the sun elevation angle. Then a seamless handoff strategy for the sinusoidal control mode is put forward to get a continuous and smooth attitude control effect. The solar panel sun-pointing accuracy of the sinusoidal yaw control mode is also analyzed. The mathematical simulation and in orbit flight results indicate that the methods are efficient and practicable in engineering application.