基于自抗扰的运载火箭主动减载控制技术

针对运载火箭穿越大风区的减载控制技术进行研究,首先对攻角反馈和加表反馈2种减载技术进行理论研究和仿真分析,得出2种方案对火箭减载都存在一定的局限性。因此引入自抗扰控制器(ADRC)技术并针对飞行减载控制对其进行改进,一方面通过状态观测器将误差补偿引入自抗扰回路;另一方面改进了自抗扰控制器中的控制律,并推导证明了新的控制律下自抗扰控制器抑制风载干扰的能力,给出了控制方程中增益的选择方法。最后以某型液体运载火箭为例在考虑其弹性振动和液体晃动条件下对比了几种方案的减载效果,仿真结果表明改进后的自抗扰控制器使飞控系统抗干扰能力增强,增大了控制律中增益选择范围,有效提高了运载火箭的减载效果,具有很强的工程应用价值。

Active disturbance rejection control method on load relief system for launch vehicles

Load relief control technology is studied for launch vehicles flying across the strong wind area. First, load relief controllers based on angle of attack feedback and accelerometer feedback were calculated, and limits of these methods were analyzed, thus an improved active disturbance rejection controller (ADRC) based on informed research was introduced into the flight control system. On the one hand, the error which was observed by status observation was introduced into the ADRC loop. On the other hand, by calculating the wind load impact on the control system, it improves the control law in ADRC and proves that aerodynamic load can be restrained by ADRC, and the method to select the gains in governing equation in the improved control law was given. At last, taking a liquid launch vehicle as an example and considering the elastic vibration and sloshing, load relief effect was analyzed with different methods. The simulation results show that after the improved ADRC method is introduced, the flight control system enhances the ability to reject disturbance, and expands the boundary when choosing a gains in the control law. With the disturbance compensation and proposed control law, the effect of the load relief system on the launch vehicle was greatly improved. This method has a great value in engineering application.