全数字挠性加速度计加矩设计与读出精度分析  

Read-out accuracy analysis and torquer-dirver design of quartz flexible accelerometer

作　　者：文一青 贺慧勇[1] 唐立军[1] 赵丹[1] 王燕[1] 商梅雪 刘文[1] 曾鹏飞[1] 

机构地区：[1]长沙理工大学物理与电子科学学院,湖南长沙410114

出　　处：《机电工程》2014年第8期1035-1039,共5页Journal of Mechanical & Electrical Engineering

基　　金：湖南省科技厅计划资助项目(2011GK3116)

摘　　要：针对石英挠性加速度计全数字闭环系统设计问题,开展了对加速度计力矩器的结构和工作原理以及与加速度数据输出的关系的分析,对加速度计力矩器的驱动和加速度计的读出精度等方面进行了研究,提出了一种数字脉宽调制(PWM)电路对力矩器进行的驱动方法,该方法不仅实现PWN对加速度计力矩器的驱动,并且该PWM数字电路的占空比参数直接作为加速度数字信号输出。利用PWM数字脉冲对加速度计力矩器进行驱动实现加速度计全数字闭环读出,对加速度计全数字读出系统进行了仿真和实验测试。研究结果表明,在一定范围内,通过调整力矩器外接电阻、PWM频率和逻辑位数,全数字挠性加速度计闭环读出电路可以测得标准偏差为1.5×10-5g,精度为10-4g的加速度值,该方法精简了电路,减少了模拟驱动电路引起的干扰。Aiming at realizing the all-digital closed-loop system of the quartz flexible accelerometer, the torquer-dirver and read-out accuracy of the accelerometer, after the analysis of the structure and working principle of the torquer and relations between torquer-dirver and read-out accuracy, were studied. The digital pulse-width modulation （PWM）circuit has been designed, which was used to drive the torquer of the accelerometer and its duty parameters was worked as the export of the accelerometer. By the means of PWM, the all-digital closed-loop system was simulated and experimented. The experimental and the simulation results show that the standard deviation of the system can reach at about 1.5×10^-5 g, and the system accuracy can reach at about 10^-4 g by adjusting the external resistor of the torquer, frequency and logic digits of the PWM within the specific limits. And this scheme simplify the circuit and reduces the interference.

关 键 词：石英挠性加速度计 力矩器 PWM驱动 

分 类 号：TH824.4[机械工程—仪器科学与技术] U666.12[机械工程—精密仪器及机械]