Orbital-Attitude Coupled Sensing Model for Power Optimization of Single-Axis Solar Arrays in Earth-Orbiting Satellites

Maximizing solar array power generation in Earth-orbiting satellites traditionally relies on sun sensors, which increase system complexity and cost. This article proposes an orbital-attitude coupled sensing model that eliminates dedicated sun sensors by integrating satellite orbital parameters and real-time attitude data. Through coordinate transformations and rotation matrix operations, the model establishes a direct mathematical relationship between solar incidence angles and satellite orbital/attitude states (yaw, roll, and pitch). A three-mode optimization framework is developed: 1) lock mode for stable operations, 2) single-axis sun-tracking mode for maximizing power under Earth-pointing constraints, and 3) orientation mode for emergency power recovery. The model enables real-time calculation of optimal solar array rotation angles via vector projection analysis, achieving 98% power consistency with sensor-based systems while reducing computational load. Experimental validation using in-orbit telemetry demonstrates eclipse duration prediction errors under 1 min and orientation accuracy within 5°. This approach provides a cost-effective, sensor-free solution for power optimization in the next-generation small satellites and resource-limited missions.