A new approach to suppress spillover instability in structural vibration control

In this paper, a new approach aiming at suppressing spillover in structural vibration control is presented. By using the null space of a modal sub‐matrix for selected modes, the higher modes neighboring the cut‐off frequency of a reduced‐order controller can be blocked from entering the feedback loop and, therefore, the control and observation spillover instability associated with these modes can be eliminated. The approach is illustrated for a cantilever plate. The performance of closed‐loop control systems using the proposed methodology and a standard ℋ 2 controller are compared. The simulation results have shown effectiveness and potentials of the proposed approach in suppressing the spillover in vibration control of large‐scale flexible systems. Copyright © 2004 John Wiley & Sons, Ltd.