Robust stabilization of an E-sail spacecraft in heliocentric displaced orbits under strong solar wind disturbances

The electric solar wind sail (E-sail) is a novel propellantless propulsion technology that generates thrust by harnessing the momentum of solar wind plasma. By leveraging this characteristic, E-sail spacecraft can perform non-Keplerian orbital missions, such as stable Earth observation, solar wind early warning, and deep-space communication relay. Traditional electric sail control methods typically rely on static assumptions regarding characteristic acceleration and employ only voltage regulation for feedback control, failing to fully account for fluctuations in the solar wind dynamic pressure. This limitation makes it difficult to maintain stability in heliocentric displaced orbits under strong disturbances. To address these challenges, this study develops an E-sail thrust model that incorporates solar wind dynamic pressure disturbances and nonlinear input characteristics, and further establishes a robust model predictive control framework for station-keeping in heliocentric displaced orbits. The proposed approach explicitly handles solar wind dynamic pressure disturbances and control constraints, thereby enhancing the station-keeping performance and control robustness of the E-sail spacecraft in complex disturbed environments. Numerical simulations demonstrate that, compared with the conventional LQR method, the proposed strategy effectively suppresses orbital deviations induced by severe fluctuations in solar wind dynamic pressure, and can maintain the target heliocentric displaced orbit even under strong disturbance conditions. The results confirm improved adaptability and control robustness. These findings provide a reliable control solution for practical applications of electric sails in complex space environments.