转子不平衡引起的同步振动是主动电磁轴承转子系统高速运行面临的一个主要激振源。通过对转子系统不平衡特性的分析,提出了一种基于不平衡识别的主动电磁轴承转子系统自适应自动平衡控制方法。该方法无需控制对象的传递函数,亦不影响原控制系统稳定的频率边界,通过对主动电磁轴承在线施加试探性激振信号,同时检测控制电流响应中不平衡频率成分的幅值和相位变化,直接识别出不平衡干扰的Fourier系数,产生精确的补偿信号,从而使转子绕其质心轴旋转。实验测试结果表明提出的自适应自动平衡方法对不平衡干扰有显著的抑制作用。
The synchronous vibration due to mass unbalance is the main source of disturbance while the shaft of active magnetic bearing (AMB rotates at high speed. In this paper, a novel auto balance method based on unbalance identification was proposed, which has negligible effect on stability margin of the original control system and no need for the transfer function of plant model. The proposed method can directly obtain the Fourier coefficients of unbalance vibration and generate the accurate compensation signal to spin the rotor about its inertial center by means of injecting a probing excitation at the AMB and measuring the changes in magnitude and phase of the control current. The experiments results show that the auto balance method presented can effectively reduce the unbalance vibration of a rotor system supported at AMB.