基于PCH模型的航天器姿态无源控制

Spacecraft attitude passivity control based on PCH model

针对存在干扰力矩的航天器姿态控制问题,从能量角度提出一种基于端口受控哈密顿(PCH)系统模型的无源控制方法。通过将姿态控制系统表示为PCH形式,并增加与姿态误差积分有关的状态,利用互联和阻尼分配无源控制(IDA-PBC)方法进行控制器设计,使得闭环系统具有期望的内部互连结构关系和能量耗散特性,所提出的控制方案能保证系统的输入-状态稳定性。进一步,考虑执行器的动态特性,利用反步法对控制指令进行补偿设计,结合指令滤波技术避免对虚拟控制量高阶导数的计算,并从理论上证明了闭环系统一致最终有界。仿真结果验证了本文所提控制方法相比于单独基于无源性控制方法的性能优势。

For the spacecraft attitude control problem in the presence of disturbance torques, a passivity control scheme based on port-controlled Hamiltonian （PCH） system model was proposed from the perspective of energy. By writing the attitude control system in a PCH form and adding the state related to integral of atti- tude error, the interconnection and damping assignment passivity-based control （IDA-PBC） method was then utilized to design the controller and provide the closed-loop system with desired internal interconnection struc- ture and energy dissipativity properties. The proposed control scheme can guarantee input-to-state stability of closed-loop system. The actuator dynamics was then considered and backstepping control scheme was utilized to compensate for control command. Combined with command filtering technique, the computation of higher order derivatives of virtual control was avoided and uniform ultimate boundedness of the closed-loop system was proved theoretically. Simulation results validate the performance advantage of the proposed control scheme over that based on passivity alone.