微米光栅加速度计力反馈系统设计

针对高分辨率微米光栅加速度计中存在的输出非线性和动态范围小的问题,提出了一种基于静电驱动的静电力反馈方法.该方法一方面将质量块位移锁定在最佳工作点,提高加速度计的线性度;同时利用静电力反馈实现微米光栅加速度计的力反馈控制,提高它的动态范围.给出了微米光栅加速度计的力反馈检测原理,建立了静电力反馈控制模型和基于力反馈的微米光栅加速度计系统的数学模型,在此基础上优化了PI控制单元,搭建了微米光栅加速度计力反馈系统,实现了力反馈控制.实验结果显示:当质量块位移锁定在最佳工作点处时,微米光栅加速度计的量程比未加力反馈时增大了33.4倍,非线性度抑制了6.4倍.

The Force Feedback System of Micro Grating Accelerometer

The dynamic range of the high resolution micron grating acceleration sensor is limited by the input wavelength and the output exists nonlinearity. In order to solve these problems, a force feedback method which is based on static electricity actuation is proposed. On the one hand the position of proof mass can be locked in the best working point, and could improve the output liner;on the other hand the dynamic range can be enlarged with the force feedback. The force feedback detection theory of micro grating acceleration is built;the static electricity control unit and the mathematical model of the system based on force feedback of the micron grating accelerometer are established and PI control unit is optimized. The force feedback experiment is built and the control is realized. The experimental results indicate that the position of the proof mass is located at the best working point;compared the result without force feedback, the range is enlarged 33.4 times and the nonlinear degree is restrained 6.4 times