微米光栅加速度计闭环检测技术优化与设计

提出一种基于Pound-Drever-Hall(PDH)调制技术的新型闭环控制方法,优化了微米光栅加速度计的信噪比和静态检测精度.采用电磁驱动实现自校准和反馈控制,相对于静电驱动降低了功耗提升了反馈效率,解决了开环检测方式下测量范围和灵敏度不可兼得的难题.对系统光学输出的干扰源进行本质分析,通过将闭环误差信号调制到高频...

Optimization and design of closed-loop detection technology of micrometer grating accelerometer

A new closed-loop control method based on Pound-Drever-Hall(PDH)modulation technology is proposed to optimize the signal-to-noise ratio and static detection accuracy of micrometer grating accelerometer.The electromagnetic drive is used to realize self-calibration and feedback control.Compared with electrostatic drive,the power consumption is reduced,the feedback efficiency is improved,and the problem that measurement range and sensitivity are incompatible in the open-loop detection mode is solved.The essential analysis of interference source of optical output of system is carried out,and the closed-loop error signal is modulated to a high frequency to eliminate the fluctuation of the light source and the interference of stray light.After a phase sensitive detector(PSD)and demodulation filter,a closed-loop error signal with high signal-to-noise ratio is obtained.The experimental results show that the signal-to-noise ratio of closed-loop detection output of micrometer grating accelerometer is improved by 21 d B relative to the open-loop detection,and the bias stability under 0.5 g acceleration input reaches 0.28 mg.