基于小推力的卫星轨道跟踪控制仿真研究

Simulation Research of Satellite Orbit Tracking Control with Continuous Low-thrust

卫星轨道机动和跟踪控制过程中,采用小推力推进能提高星上燃料利用率,增加航天器有效载荷的质量,从而降低卫星发射质量与成本。针对连续小推力卫星轨道机动和跟踪控制过程中,传统方法无法保证解的近优性和优化参数多的问题,提出了一种新的轨道跟踪闭环控制算法。新算法通过极大值原理,将燃料最优连续推力轨道转移问题转化为最优控制两点边值问题,然后采用无迹卡尔曼滤波(Unscented Kalman Filter, UKF)参数估计算法获得燃料最优转移轨道,并采用数据拟合的方式对最优轨道进行处理获得参考轨道。最后根据轨道要素变化量分段跟踪参考轨道,通过对半解析法理论的权重参数进行不断调整,得到连续小推力燃料最优参考轨道跟踪的最优解。仿真结果表明,新方法只需要优化少量参数,能有效实现卫星对目标轨道的高精度跟踪控制。

In order to solve the problem that traditional methods can not guarantee the near optimality of solution and have too many optimization parameters in the process of orbit maneuver and tracking control of continuous low-thrust satellite,this paper puts forward a new closed-loop control of orbital tracking algorithm.According to the maximum principle,the new algorithm was used to transformed the problem of optimal continuous thrust orbit transfer into a problem of two-point boundary value of optimal control.Then,the Untraced Kalman Filter(UKF)parameter estimation algorithm was used to calculate the optimal fuel transfer orbit.Meanwhile,a data fitting method was used to process the optimal orbit,so as to obtain a reference orbit.Finally,the reference orbit was tracked by segment based on the variation of orbit elements.By adjusting weight parameters of the semi-analytical method,the optimal solution of optimal reference trajectory tracking of continuous low-thrust fuel was obtained.Simulation results show that the new method optimizes only small amounts of parameters.Meanwhile,this method can effectively achieve high-precision tracking control of satellite for the target orbit.