硅微谐振加速度计的模态分析与实验  

Modal analysis and experiment of a silicon micro-machined resonant accelerometer

作　　者：张秀丽[1] 何晓飞 尹永刚[2] 方政翔 韩丰田[2] ZHANG Xiuli;HE Xiaofei;YIN Yonggang;FANG Zhengxiang;HAN Fengtian(School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing 100044,China;Department of Precision Instrument,Tsinghua University,Beijing 100084,China)

机构地区：[1]北京交通大学机械与电子控制工程学院,北京100044 [2]清华大学精密仪器系,北京100084

出　　处：《中国惯性技术学报》2019年第5期690-694,700,共6页Journal of Chinese Inertial Technology

基　　金：国家自然科学基金资助项目（41774189)

摘　　要：针对硅微谐振加速度计在进行结构设计时,如何根据模态特性选取工作模态这一问题,比较分析了加速度计工作在两种不同振动模态下的性能参数。首先采用刚度法分析了谐振器的振动特性,得出能够反映谐振器振动状态的两种模态即同相振动模态和反相振动模态,结合理论推导和仿真结果得出两种振动模态下谐振频率差值与标度因数差值呈线性关系;其次通过分析两种振动模态下的能量分布情况,得出两种振动模态下谐振器的品质因数与振梁振动幅值之间的关系,同相模态振动一个周期所消耗能量约为反相模态所消耗能量的2倍;最后通过评估硅微谐振加速度计的噪声,阐明了两种振动模态下部分噪声分量不同的原因并进行了实验验证。实验结果表明,在相同驱动电压下,同相模态相比反相模态总体噪声增大25.7%。该研究为设计硅微谐振式加速度计时,确定谐振器的振动模态及驱动方案提供了参考依据。In order to solve the problem of how to select the working mode according to the modal characteristics in the structural design of silicon micro-resonance accelerometer(MRA),the performance parameters of the accelerometer under two different vibration modes are compared and analyzed.Firstly,the vibration characteristics of resonators are analyzed by the stiffness method,which shows that the resonator exhibits two major operation modals reflecting its vibration state,i.e.the in-phase and anti-phase modes.The linear relationship between the resonance frequency difference and scale factor difference in the two modes is presented by theoretical analysis and simulation.Then,the relationship between the quality factor of resonators and the amplitude of vibration beams is obtained by analyzing the energy distribution of a MRA operating at two vibration modes.A quantitative comparison of the associated energy consumption shows that the energy consumption of in-phase mode is about twice as much as anti-phase mode in a cycle.Finally,the accelerometer noise components in the two vibration modes are evaluated by analyzing various noise sources and are verified by experiments.Experiment results indicate that the noise level of in-phase mode is increased by 25.7%compared with that of anti-phase mode in the same driving voltage.This work will be helpful for structure designers of MRAs to select the optimal vibration mode and driving scheme.

关 键 词：硅微谐振加速度计 模态分析 同相模态 反相模态 

分 类 号：TN965.5[电子电信—信号与信息处理]