Sun-pointing control system for satellite and control method of sun-pointing control system

The invention provides a sun-pointing control system for a satellite and a control method of the sun-pointing control system. The sun-pointing control system comprises a framework, a top, a star sensor, a sun sensor, a circuit, a data circuit and a satellite-borne control assembly. The sun vector under the system is worked out by adopting different attitude sensors through different methods according to the operating mode of the system, the sun sailboard normal vector under the system is calculated according to satellite structure design information, the error quaternion is defined and derived according to vector rotation, the error angular speed is calculated and substituted into the PIC control law, and a calculated control command is transmitted to a counteraction flywheel, so that sun-pointing control is completed. By the adoption of the control device, sun-pointing control of the satellite under two operating modes can be achieved, on-board control algorithms and parameter setting are unified, and a sun-pointing maneuvering path of the satellite is made shortest; and the sun-pointing control system and the control method of the sun-pointing control system can be widely applied to various satellites needing sun-pointing control.