Electric field instrument and electric field measurement method

Abstract

An electric field instrument comprises a detection device, a signal processing device and a data analysis device. The detection device sends electric field signals to the signal processing device; a movable sheet, a drive device thereof, two groups of fixed sheets and a sensor are arranged in the detection device; the signal processing device comprises a differential module; and the two groups of the fixed sheets in the detection device are respectively connected with two operational amplifiers to constitute two input circuits of the differential module. An electric field measurement method comprises the following steps: two groups of electric field alternating signals are obtained through time-sharing and shielding of the two groups of the fixed sheets by the movable sheet, the obtained electric field alternating signals are subjected to the signal processing by a plurality of signal processing processes for outputting the electric field value, and the signal processing processes comprise the steps of carrying out the differential amplification of the two groups of the electric field alternating signals after the filtering and the frequency selection amplification treatments. The electric field instrument and the measurement method of the invention can inhibit the instability of the circuit caused by the temperature and the external electromagnetic interferences, improve the noise suppression ability and allow the electric field measurement to be stable and reliable. 一种电场仪，包括探测装置、信号处理装置和数据分析装置，探测装置将 电场信号传送于信号处理装置，探测装置内设置有动片及其驱动装置、两组定 片和传感器，信号处理装置包括差分模块，探测装置内的两组定片分别与两运 算放大器连接以组成差分模块两输入电路。一种电场测量方法，由动片分时屏 蔽两组定片得到两组电场交变信号，将获取的电场交变信号经由多个信号处理 过程进行信号处理以输出电场值，信号处理过程包括将两组电场交变信号经滤 波与选频放大处理以后进行差分放大的步骤。本发明的电场仪及测量方法，抑 制了由于温度和外界电磁干扰所引起的电路的不稳定性，提高了噪声抑制能 力，使得电场的测量变得稳定可靠。