Abstract: In view of the least sun avoidance angle of the camera，and the large baffle beyond the fairing cap，the algorithm of the least sun avoidance angle based on non-imaging duration was studied when the satellite avoids the sun by yaw attitude maneuver.Then，the outer baffle′s modeling equations based on three panels and the cylinder were proposed.It also offered optimization method of the panels′ upper edge.Kinds of scarfed outer baffle were designed in typical condition with the same effect of sun avoidance.After the outer baffles′ 3D modeling in Pro/ E and shadow analysis，the results show that the shadow ratio is 100% when solar elevation angle is at various degrees.It means that the bottom of inner baffle will not be shined.This verified the correctness of outer baffle′s modeling equations and the optimization method of the panels′ upper edge.The article achieved the effect of sun avoidance with 1/3 area of traditional cylinder outer baffle.

Key words: sun avoidance, non-imaging duration, yaw attitude, scarfed outer baffle, shadow analysis