基于偏航观测器的偏置动量卫星姿态控制

Attitude control for momentum biased satellites based on yaw observer

研究了基于偏航观测器的三轴稳定偏置动量对地定向卫星姿态控制问题.由于采用的红外地平仪无法测量卫星的偏航信息,提出了一种基于偏航观测器的姿态控制方案.针对俯仰回路,利用测量的俯仰角实现了俯仰回路姿态控制;滚动/偏航回路的设计由2部分组成:基于偏航观测器的PD控制器和飞轮解耦环节.整个系统采用动量轮和反作用飞轮作为执行机构,磁力矩器提供的磁矩与地磁场作用产生的力矩实现了飞轮的动量卸载.最后对卫星姿态控制系统进行了仿真研究,结果表明,所设计的控制方案在飞轮输出力矩工作范围内,可使卫星达到很高的姿态控制精度.

Attitude control problem of a three-axis stabilized, momentum biased, and nadir-pointing satellite is investigated based on yaw observer. Since the measurement of the yaw angle is unavailable by horizon sensor, an attitude control scheme of the satellite is proposed based on yaw observer. The pitch control is attained by the measurement of the pitch angle. The roll/yaw design is composed of two parts; a PD controller based on yaw observer and a wheel decoupling function. The satellite considered is actuated by momentum and reaction wheels. Magnetic torqrods generate magnetic dipole moments whose interaction with the Earth magnetic field can produce magnetic torques necessary to remove the excessive momentum of wheels. Numerical simulation results show that high pointing accuracy is achieved within the range of wheel torques.