非同位配置主动结构的稳定性分析

Research on stability of the Active Structure with non-collocated

与同位配置的主动结构相比较,非同位配置的主动结构的开环零-极点不再是沿着虚轴方向相间分布,而是发生了零-极点跳跃现象,致使闭环系统的根轨迹延伸至右半平面,导致主动结构的不稳定。由于零-极点的跳跃,虚轴附近的将产生的相位误差,因此在这对零-极点之间及其附近频率范围内,保证闭环系统稳定性的唯一方法是,在此频率范围内使开环系统具有增益稳定性。

The non-collocated actuator and sensor pairs not longer holds to alternating poles and zeros on the imaginary as the collocated ones. And the root locus plot may experience severe alterations for small parameter changes. Therefore, a pole-zero flipping near the produces similarly a phase uncertainty of 360° in the frequency range between the pole and the zero. It appears that the only way the closed-loop stability can be guarranteed in the vicinty of a pole-zero flipping is to have the open-loop system gain-stabilized in that frequency range.