The solar occultation observation or solar calibration of the payload requires the sunlight or the diffuse reflection of sunlight to enter the field of view. It’s important to consider the variation of azimuth and elevation angle from the. The article analyzes the impact of in-orbit drift angle control and LTAN drift of 8 years in-orbit towards the solar vector. On the basis on the occultation period and solar calibration period, the range of the solar driven angle, the solar observation FOV, timing of the calibration and the optimal LTAN range are analyzed. The analysis method can provide reference for similar payload design and orbital control design with solar observation requirements.