航天器环境干扰力矩的闭环辨识与补偿

研究引入干扰力矩辨识的方法提高三轴稳定航天器在稳态运行期间的高精度指向控制问题.基于航天器的稳态输出数据和系统传递函数,对环境干扰力矩的完整模型进行闭环辨识.其中采用改进的特征系统实现相关算法和多元线性回归法辨识环境干扰力矩的模型参数,最后使用前馈控制对所辨识的环境干扰力矩实现在线补偿.分析和仿真结果表明,该方案能有效地克服不确定的环境干扰力矩对姿态稳定度的影响,提高在轨运行航天器的姿态稳定精度.

Closed-loop Identification and Compensation for Environmental Disturbance Torques Acting on Spacecraft

In this paper, disturbance torque identification method was proposed to improve the precise attitude control of three-axis stabilized spacecraft for steady-state operation. Based on output-only data for steady state and the system transfer function, closed-loop identification was used to obtain the complete models of environmental disturbance torque. Meanwhile , the modified eigensystem realization algorithm with data correlation ( ERA/DC) and multivariate linear regression method were used to obtain the disturbance model parameters. By choosing feedforward control method, we can achieve online compensation for the identified environmental disturbance torques. Simulation results show that the approach can compensate the uncertain environmental disturbance torques effectively, and improve the steady-state precision of spacecraft attitude control system.