基于会切场推力器的无拖曳控制系统建模

Drag-Free Control System Modeling Based on Cusped Field Thruster

为了研究航天器无拖曳控制系统的建模方法、评估会切场推力器性能以及传感器测量误差对无拖曳控制系统性能的影响,基于会切场推力器的性能实验数据,采用轨道动力学理论,大气阻力模型和PID控制设计方法完成了无拖曳控制系统设计,并对推力器推力分辨率、推力器瞬态响应时间以及传感器测量误差对闭环控制系统性能的影响进行了研究。仿真结果表明控制系统工作性能良好,推力分辨率以及传感器的测量误差对系统性能影响较小,但是推力器的响应延迟对控制系统精度造成较大影响,需要在后期的推力器设计中进行进一步的优化改进。综合考虑以上因素后,闭环系统在航天器速度方向的最大位移误差为747.51nm,最大速度误差为733.36nm/s,该仿真结果说明了会切场推力器应用于无拖曳任务的可行性。

In order to study the modeling method of drag-free control system of spacecraft and assess the effects of cusped field thruster performance and sensor measurement errors on control system performance, a dragfree control system is designed based on orbit dynamic theory, atmospheric drag model, PID control method and the experimental data of the eusped field thruster. Furthermore, the effects of thrust resolution, transient response time of thruster and sensor measurement errors on closed loop system are analyzed. The simulation results show that the control system has good performance and thrust resolution and sensor errors have slight influence on the overall system. But thruster response delay has a greater impact on control system precision, which needs fur- ther optimization in later studies. Considering the above factors, the maximum displacement error of closed loop system in the spacecraft velocity direction is 747.51nm, the maximum velocity error is 733.36nm/s. The simula- tion results show the application feasibility of cusp field thruster in drag-free missions.