关键词: 电磁驱动, 微驱动器, 动态, 吸合

Abstract:

The analysis of the pull-in of magnetostatic micro-devices (MMD) has been done using quasi-static assumptions traditionally. The models established are not exact enough because of the dynamic characteristics of the devices. So it is necessary to establish the dynamic models, which will be more suitable to the normal and could help the design and control of the micro-devices. Based on the energy balance equations, the dynamic pull-in characteristics of two MMD with the step input magneto motive force are analyzed, with the reluctance of the magnetic core m considered and the effect of system damping neglected. The results indicate that as to the parallel-plate device, the critical dynamic pull-in displacement of the mobile part is 1.5 times that when quasi-static pull-in occurs; as to the torsional device, the critical dynamic pull-in angle increases with the decrease of m, and changes from 1.29 to 1.46 times that when quasi-static pull-in occurs. The critical step inputs MMF of the two MMD are about 91.9％ and 91.2％ the quasi-statically predicted pull-in MMF of each MMD respectively.

Key words: magnetostatic actuated, micro-actuator, dynamic, pull-in