基于高速解调电路的新型手持式工频电场检测系统

摘要

Power frequency electric field detection has very important application prospect in the fields of fault detection of transmission lines and body protection in strong electromagnetic field.Aiming at the features of the output signal from the micro-machined electric-field sensitive structure,a preamplifier circuit is designed to amplifying the weak output signal.Based on phase sensitive detection principle,an analog demodulation circuit is designed.It achieves faster response rate,signal processing is realized based on ARM microcontroller,a novel handheld measurement system of power frequency electric field is developed. The detection performance under transmission lines shows that the system has good detection performance,the detection results have good consistency with the electric field measuring instrument of Germany Narda.%基于高性能的微机电系统(MEMS)电场敏感芯片进行工频电场检测,设计了前置放大电路对芯片输出的微弱信号进行二级放大;基于相敏检测原理,设计了一种可抑制背景干扰噪声的模拟解调电路,提高了系统的响应速度;基于ARM微控制器实现了信号的处理,最终成功研制了一种新型手持式工频电场检测系统.输电线路下电场检测实验表明:系统具有良好的检测性能,检测结果与德国Narda电场测量仪具有较好的一致性.