磁悬浮控制力矩陀螺的动框架效应及其角速率前馈控制方法研究

在磁悬浮控制力矩陀螺中,局限于磁悬浮轴承系统的动态响应速度,框架的转动将使转子轴的角位移和轴心跳动量显著增大(动框架效应),甚至碰撞保护轴承,严重影响磁悬浮系统的稳定性。本文建立框架转动时的磁悬浮转子相对运动模型,分析了框架转动对磁悬浮转子的单方向作用,在Simulink仿真的基础上提出一种抑制动框架效应的角速率前馈控制方法。实验结果表明,磁悬浮轴承采用角速率前馈控制后,转子跳动量被抑制到原来的18％,大大提高了控制力矩陀螺磁悬浮系统的稳定性,同时还改善了控制力矩陀螺的力矩输出特性。

Moving-gimbal Effects and Angular Rate Feedforward Control in Magnetically Suspended Rotor System of CMG

In the magnetically suspended rotor system of control moment gyroscope (CMG), limited by system dynamic response speed, axis run-out will grow significantly owing to gimbal revolve, even rotor contacting with the touchdown bearing, which reduces system stability severely. This paper firstly set up relative motion dynamics model of suspended rotor with revolving gimbal. Then the unidirectional effects of revolving gimbal to rotor motion were analyzed. According to simulation results using Simulink, a new method of gimbal angular rate feedforward control for run-out depression in magnetic bearing system was presented. Utilizing CMG developed by Beijing University of Aeronautics and Astronautics, experiments have been performed to verify the efficiency of feedfordward control. Rotor run-outs are suppressed to 18% compared to that without feedforward, which improves magnetic bearing system stability and moment-output performance of the CMG.