磁悬浮控制力矩陀螺动框架效应的FXLMS自适应精确补偿控制方法仿真研究

在磁悬浮控制力矩陀螺（CMG）中，框架运动对磁悬浮转子支承系统的扰动可以采用角速率前馈加以补偿，但前馈系数固定时的补偿精度受磁轴承系统模型误差影响而显著下降。为了提高补偿精度，本文针对MIMO磁悬浮转子系统，提出一种基于FXLMS（filtered-X least mean square）算法的自适应前馈方法，采用梯度估计和最速下降策略推导前馈权值更新算法，并根据算法收敛性和收敛速度设计收敛因子和权初值。仿真结果表明，该方法收敛速度快，抗噪声能力强，相同模型误差情况下使转子的动框架位移降低到固定特性前馈时的20％，大幅度提高了动框架前馈补偿精度，有利于进一步提高磁悬浮CMG的力矩输出精度。

Accurate Compensation of Moving-Gimbal Effects Based on FXLMS Algorithm in Magnetically Suspended Control Moment Gyroscope

In magnetically suspended control moment gyroscope(MSCMG),disturbance to rotor supporting system resulted from gimbal revolve can be depressed by means of gimbal angular-rate feedforward,but compensation precision of feedforward with invariant characteristic is reduced by system model errors significantly.The purpose of this study is to introduce adaptaive feedforward into MIMO magnetic bearings system based on FXLMS algorithm to eliminate moving-gimbal disturbance.The algorithm of feedforward weight iteration was deduced via gradient estimation and steepest descent strategy,and convergence factor and initial feedforward weight were designed according to convergence property and convergence velocity.Simulation results showed that feedforward with FXLMS adaptation converged swiftly and rotor run-out decreased to 20% than that without adaptation corresponding to the same current stiffness errors.It is concluded that FXLMS feedforward could raise compensation precision remarkably so as to improve precision of output moment of MSCMG.