基于压电传感器的零点漂移改善电路的研究

Research on Zero-drift Improvement Circuit Based on Piezoelectric Sensor

摘要:

针对弹药发射及侵彻过程中高速冲击信号的测量需求，本文设计了一种基于电荷传感器的高冲击弹载侵彻加速度测量电路，解决了常规弹载记录仪在侵彻过程中压电传感器因高过载而产生的严重信号值零点漂移的现象。通过对压电传感器的零点漂移现象的机理分析以及推导电荷转换等效电路中零点漂移电压的相关表达式，提出在前端采集的调理电路中用晶体管与运算放大器搭建了加推挽电流放大级的电荷放大器的方案，增强电路驱动能力，加快压电传感器放电速度。本设计可替代例如小波分析等事后处理数据消除零点漂移的算法，在信号源头处解决零点漂移现象，满足测量常规弹药侵彻过程高过载连续动态特性的实时性测量，对研究这类工程问题的人员实现对测量电路改进具有指导意义。

Abstract:

Aiming at the measurement demand of high-speed impact signal in the process of ammunition launch and penetration, a high impact projectile penetration acceleration measurement circuit based on charge sensor is designed in this paper, which solves the phenomenon of serious signal value zero drift caused by high overload of piezoelectric sensor in the process of penetration of conventional missile recorder. Through mechanism analysis on the phenomenon of piezoelectric sensor's zero drift and derivation of charge convert zero drift in the equivalent circuit voltage related expression, is put forward in the front-end acquisition circuit with operational amplifiers and transistors built with push-pull amplifier stage current charge amplifier, enhance the capacity of drive circuit, speed up the discharge of piezoelectric sensor. This design can replace the algorithms such as wavelet analysis to eliminate zero shift after processing data, and solve the zero shift phenomenon at the signal source, so as to meet the real-time measurement of high overload continuous dynamic characteristics of conventional ammunition penetration process, which has guiding significance for the realization of the measurement circuit improvement for the personnel studying this kind of engineering problems.