中文摘要：

利用电动绳系实现空间碎片自主离轨有广阔的应用前景。受洛伦兹力矩和重力梯度力矩作用，绳系姿态将在当地垂线附近振荡。首先采用拉格朗日法建立电动绳系面内外姿态动力学模型；随后结合国际地磁场模型，给出洛伦兹力和洛伦兹力矩的计算方法；最后结合姿态动力学模型和高斯摄动方程，建立了电动绳系离轨数值仿真模型，在考虑无摆角、仅有面内摆角、有面内外摆角的条件下，对电动绳系离轨过程进行仿真对比。仿真结果说明，电动绳系姿态振荡对离轨有明显影响，只有考虑绳系姿态，才能精确预测轨道参数的变化。

英文摘要：

Using the electro-dynamic tether system for space debris deorbit has a broad application pros- pect. Under the torque generated by Lorentz force and gravity gradient, the electro-dynamic tether librates a- long the local vertical. Base on Lagrange principles, the attitude dynamic associated with in and out-of-plan li- bration is established at first. The international earth＇s magnetic model, the Lorentz force and torque are calcu- lated. Finally, by combining the attitude dynamics model and Gauss perturbation equation, the numerical model for electro-dynamic tether deorbit is established, and both the libration and non-libration deorbit mission are simulated, respectively. Simulation results show that the in and out-of-plan libration exist and have an obvious effect on the deorbit system. Only considering the attitude of the electro-dynamic tether system, orbital ele- ments change can be convinced.