双定子地面电场仪雷电监测技术的研究

摘要

Aiming at the rotary ground electric field instrument has some problems such as high input impedance, weak signal which easy to leak, and easy to be interfered by electromagnetic wave in space, a new type of differential double-stator electric field sensor is designed in this paper.The common mode effect was eliminated by the dual stator output signal, and the leakage of the signal was eliminated by the active equipotential shielding of the weak alternating small signal of the double stator output, so as to improve the sensitivity of the system.The sensor senses two current signals, which would be converted to voltage signals by I-V converter.The voltage signal would be amplified by an amplifier and filtered by the fourth-order bandpass filter to improve the signal to noise ratio.The synchronous signal of the measured signal was obtained by using the photoelectric switch sensor, and then would be processed by the phase-locked amplifier to obtain the direct voltage which was directly proportional to the field strength.The experiment shows that the system can measure the intensity of atmospheric electric field in real time, which can provide necessary basis for lightning monitoring and warning.%针对目前旋转式地面电场仪输入阻抗高、信号微弱易泄露,易受空间电磁波的干扰,设计了一种新型双定子差分式电场传感器.通过双定子输出信号进行差分消除共模影响,对双定子输出的微弱交流小信号进行有源等电位屏蔽消除信号的泄露,提高系统的检测灵敏度;传感器感应得到两路电流信号经过I-V转换器转为电压信号,通过放大器对信号放大,四阶带通滤波器对信号进行滤波,提高信号的信噪比;利用光电开关传感器得到测量信号的同步信号,采用锁相放大器对信号进行处理得到与场强成正比例关系的直流电压.试验表明,该系统能够实时测量大气电场的强度,可以为雷电监测预警提供必要的依据.