重力梯度仪用石英挠性加速度计伺服线路噪声分析  

Noise analysis of QFA servo circuit for gravity gradiometer

作　　者：雷立铭[1] 舒晴[2] 杨晔[1] 程关德[1] 

机构地区：[1]天津航海仪器研究所,天津300131 [2]中国国土资源航空物探遥感中心,北京100083

出　　处：《物探与化探》2015年第B12期22-27,共6页Geophysical and Geochemical Exploration

基　　金：国家高技术研究发展计划(863计划)(2011AA060501)

摘　　要：高分辨率加速度计是重力梯度测量的核心传感器,其中石英挠性加速度计是目前重力梯度测量中主要使用的加速度计,对其噪声性能有严格的要求。为此提出一种新型基于交流恒压激励的差分电容检测原理的石英挠性加速度计低噪声伺服前放电路,在此基础上,结合加速度计表体参数和伺服线路校正参数,研制出完整的伺服线路。在系统工作频率上对伺服系统带来的噪声影响做出定量分析,其对系统的总体噪声影响约为1.0×10-10g/槡Hz(0.5 Hz),可以满足10 E以上分辨率的重力梯度测量需要。High resolution accelerometer is a kernel sensor for gravity gradiometer measurement. The QFA is mostly used in this measurement at present,so the requirement of noise performance is very strict. Therefore,a new type low- noise QFA preamplifier is put forward to detect differential capacitor based on constant AC voltage stimulation. On such a basis,the integral servo circuit is designed in combination with the parameters of QFA and servo circuit calibration. The quantitative analysis of the noise influence of servo circuit has been done,the noise contribution of the circuit to the QFA servo system is approximately 1. 0 × 10- 10槡g / Hz at 0. 5Hz. This can satisfy the needs of gravity gradiometer measurement above 10 E resolution.

关 键 词：差分电容检测 交流恒压激励 低噪声 重力梯度测量 

分 类 号：U666.122[交通运输工程—船舶及航道工程]