小卫星动量轮非线性特性建模与仿真方法

动量轮是三轴稳定卫星姿态控制的关键执行部件。由于小卫星本身的转动惯量较小，微弱的干扰力矩有可能导致整个卫星控制系统性能下降。因此，建立一个基于动量轮实际物理特性的理论仿真模型对小卫星姿态控制系统设计至关重要。本文提出了一种多输入多输出非线性建模方法，并给出了基于SIMULINK的动量轮物理特性仿真模型。该模型可以同时输出动量轮所有特征参数的实时值。最后，通过开环和闭环控制数值仿真，对模型进行了验证。数值实验结果与实际物理部件的测试结果一致。本方法可以为小卫星姿控系统的仿真提供一个有效的、精确的、可以直接应用的部件级模型。

Non-linear modeling and simulation technique for momentum wheel of small satellites

Three-axis stabilization is the general control technology of satellites.A momentum wheel is the key actuator of attitude control system of all three-axis stabilization satellites.As the moment of inertia of small-satellite is smaller,any weak disturbance torque may make the satellite out of control.Therefore,it is important to establish an accurate physical characteristics simulation model close to the real case.In this paper,a MIMO (multi-Input and multi-Output) non-linear model was presented.In details,a design example was discussed.The model can output the real-time value of all characteristic parameters for the momentum wheel.Finally,the model was evaluated by the open-loop and close-loop control system simulation.The analysis and numerical results are consistent with the real physical characteristics.It provides a valid,precise sub-model which can be used directly in attitude control system simulation model of small satellites.