Bi-level multi-objective optimization of the structure and attitude for space solar power station

To utilize space solar energy efficiently, this study focuses on the optimization of multi-rotary joints space solar power satellite (MR-SSPS), which is designed to efficiently collect and transmit solar energy to Earth. A constraint multi-objective optimization model is proposed for the MR-SSPS, which encompasses three objectives: truss mass, structural stiffness, and attitude control energy. A bi-level optimization method is proposed, considering the characteristics of the structure and attitude control models. The first-level optimizes the structure of the solar array system and truss, while the second-level optimizes the attitude controller. The mass and certain structural parameters serve as correlation variables linking the two levels. To enhance efficiency, a database and parallel computing are employed. Compared to the traditional multi-objective optimization approach, the proposed bi-level method achieves better solutions in both accuracy and efficiency. The optimized MR-SSPS structure meets attitude control accuracy constraints while reducing mass and energy consumption. This research provides insights into the design of MR-SSPS and demonstrates the effectiveness of the bi-level optimization approach for complex engineering problems.