Research on Variable Structure and Adaptive Control for Strap-on Rocket

固体捆绑运载火箭变结构自适应控制

陈曦,刘玉玺,汪轶俊

（上海宇航系统工程研究所）

创新点说明：

对于新型固体捆绑火箭而言,由于箭体安装固体助推器,存在推力偏差较大、推力同步性较大的问题,导致火箭的结构干扰增大。安装尾翼外干扰增大,如经过大风区时,风干扰对箭体产生较大的影响。同时考虑建立动力学模型的过程中存在的参数不确定性、参数摄动、三通道间耦合的问题,传统的控制方法难以满足新型固体捆绑火箭的要求,因此本文率先将基于模型参考的变结构自适应控制方法应用于固体捆绑运载火箭上。

研究目的：

本文针对固体捆绑运载火箭控制系统的特点,应用变结构自适应控制理论,设计适用于固体捆绑运载火箭的控制系统,保障固体捆绑运载火箭的正常飞行。

研究方法：

（1）建立固体捆绑运载火箭动力学模型,考虑模型中参数不确定性、未建模动态及通道间耦合;

（2）分析固体捆绑运载火箭存在的干扰,例如：四个固体助推带来的推力偏差、推力不同步性、推力线偏斜,质心横移、芯级、发动机及尾翼安装误差、芯级发动机液体燃料晃动、箭体弹性振动等各类结构误差及风干扰等外干扰;

（3）针对固体捆绑运载火箭设计变结构自适应控制律的设计并证明其稳定性;

（4）Simulink仿真分析验证。

结果：

本文使用变结构自适应控制理论设计的控制系统可全局渐进稳定,三通道姿态角跟踪误差较小,姿态角收敛速度较快,系统性能良好,可有效处理各类结构干扰、外干扰、气动参数不确定性及未建模动态等问题,该控制系统的动态特性及控制品质良好,具有工程应用的前景。

结论：

本文将基于模型参考的变结构自适应控制方法应用于新型固体捆绑运载火箭的控制系统的设计中。给出了仅有俯仰方向有大姿态变动的条件下的火箭动力学偏量模型,并在此基础上设计变结构自适应控制律,同时证明了该控制系统的稳定性。本文通过理论及仿真分析,证明了变结构自适应控制理论在新型固体捆绑运载火箭上的应用可行性,具有一定的工程应用前景。

关键词：运载火箭;模型参考;变结构控制;自适应控制

     

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