空气阻尼对扭臂式静电驱动结构pull-in电压的影响

Effect of Air Damping on pull-in Voltage of Torsion Electrostatic Micro-actuator

摘要:

基于扭臂式静电驱动结构的基本模型, 在忽略和考虑空气阻尼作用的两种情况下, 分别采用能量法和力电耦合分析方法得到扭臂式静电驱动器的pull-in电压。通过对比两种情况下的pull-in电压, 得出了驱动结构参数变化时空气阻尼作用对pull-in电压的影响。结果表明, 在一定范围内, 随着上电极长度、上电极宽度的增加以及上下电极之间间距的减小, 空气阻尼作用对pull-in电压的影响逐步增大; 并且当上电极宽度增大或者上下电极之间间距减小到一定程度时, 空气阻尼作用力甚至可以与驱动的静电力达到同一数量级, 此时必须考虑空气阻尼作用的影响。

Abstract:

Based on the model of torsion electrostatic micro-actuator, energy method and electro-mechanical coupling method are used respectively to get the Pull-in voltages without and with considering air damping. By comparing the Pull-in voltages under the two circumstances mentioned above, the effects of air damping on Pull-in voltage can be obtained. The results show that, the influence of air damping increases if the width or length of the top electrode increases or the spacing between the top and bottom electrode decreases. The air damping force can even reach the same order of the electrostatic force with the increase of width of top electrode or the decrease of spacing between top and bottom electrode. In this case, the influence of air damping must be considered.