先进天基太阳天文台卫星（ASO-S）主要任务是对日观测。为实现高精度高稳定度需求，卫星采用星敏感器（STR）和光纤陀螺的扩展卡尔曼滤波算法进行姿态确定。在轨因受到地气光影响，卫星装配的3台STR交替有效。为了减弱装配测量偏差引起定姿使用星敏切换时的姿态指向控制误差，需统一3台STR的测量基准。同时，修正STR相对载荷测量基准的偏差，提高卫星对日指向控制精度。ASO-S载荷之一的白光太阳望远镜（WST）入轨后即可开机测量太阳全日面图像，经图像处理后得到太阳中心二维指向偏差角。同时，另一载荷太阳导行镜（SGT）可直接测量太阳中心二维指向偏差角。结合载荷对日观测数据和卫星对日指向控制导引律，提出一种星载STR安装矩阵在轨修正算法。通过仿真验证了STR安装矩阵修正算法的正确性，与仿真中星敏模型的安装矩阵相比，使用10幅WST全日面图像计算STR安装矩阵的精度优于3″；利用300 s SGT数据计算STR安装矩阵的精度优于0.2″。以ASO-S在轨遥测数据进行算法验证，卫星对日指向控制偏差与SGT测量太阳中心偏差角间的偏差值优于15″，将STR相对SGT的装配测量精度提高了1.5倍。

The mission of the Advanced Space-based Solar Observatory Satellite （ASO-S） is to observe the Sun activity. To satisfy the requirements for high precision and high stability， the extended Kalman filtering algorithm based on measurements of Star Tracker （STR） and fiber optic gyro is used for attitude determination. The reflected light coming from atmosphere of earth can affect the STR， so 3 on-board STRs will be available alternately. Because of assembling error of STRs， there will be a large attitude control error when the STR used for attitude determination changes. To reduce this control error， unification of the measurements obtained from the 3 STRs is necessary. Meanwhile， the assembling error of STR with respect to the measuring basis of payload should be calibrated for higher precision of attitude control. One of the main payloads on-board ASO-S named the White-light Solar Telescope （WST） can get full solar images shortly after entering the orbit. Then， the two-dimensional heliocentric deviation angle can be got by solar image processing. At the same time， another payload named Sun Guide Telescope （SGT） on ASO-S can directly measure the two-dimensional deviation angle between its detector center and the solar center. An on-orbit modification algorithm for installation matrix of STR is proposed by using solar observation data of payload and the guidance law of the satellite for sun pointing control. Mathematical simulation is used to validate the correctness of the proposed algorithm. In comparison with the simulation model of STR， the precision of installation matrix calculated by 10 full solar images of WST is less than 3″， and the result calculated by 300 s measurements data from SGT is less than 0.2″. The on-orbit telemetry data of ASO-S are used to validate this algorithm. The deviation error between the sun pointing control error and deviation angles measuring from SGT is less than 15″， so the assembling precision between STR and SGT is improved 1.5 times.