航空发动机静电传感器及检测电路分析设计

Analysis and Design of the Electrostatic Sensor and Detection Circuit for Aircraft Engine

静电传感器的探极被放置于航空发动机尾气通路中,是获取静电信号的直接元件。基于Matlab和COMSOL对探极的感应特性做了相关研究,得出了静电传感器可等效为低通滤波器的结论。为解决电压前置放大器抗干扰性差这一弊端,设计了电荷灵敏前置放大器、成型电路、陷波器。验证表明,设计的检测电路能够对微弱电荷信号进行无失真放大,抗干扰性较好,为分析静电感应信号的特性奠定了基础。

The probe of electrostatic sensor placing in the tail gas path of aircraft engine is the direct element for obtaining electrostatic signal. Based on Matlab and COMSOL, the induction characteristics of the probe are researched, and it is concluded that the electrostatic sensor can be equivalent to low-pass filter. To solve the malpractice of poor anti-interference performance of the voltage pre-amplifier, the charge sensitive pre-amplifier, forming circuit, and notch filter are designed. The validation shows that the detection circuit designed can enlarge the weak charge signal without distortion, and features better anti-interference capability; this laid the foundation for analysing characteristics of the electrostatic induction signals.