基于平行板的低频电场标准装置

Low-Frequency Electric Field Standard Device Based on Parallel Plates

由于各厂家生产的探头参差不齐,不同探头的性能也不尽相同,电场标准装置的研制就显得尤为重要。为了满足低频高场强电场探头的校准要求,采用平行板法研制了一套低频电场标准装置。装置由两块边长1 m,板间距0.5 m的方形铝板组成。频率范围为DC~10 kHz,电场强度范围为0~3000 V/m。通过理论分析、软件仿真和测量实验,研究了边缘效应、极板材料、结构形状、工作频率等因素对平行板产生标准电场的影响,并进行了不确定度评定。提出了新的测量模型,并对极板电压、极板间距、平行板内场均匀性、探头夹具、探头对准、平行板有限尺寸和探头影响七个因素导致的不确定度分量分别进行了评定,得到扩展不确定度为U=6.8%(k=2)。结果表明,研制的电场标准装置能够满足低频电场探头的校准要求。

Due to the varying quality of probes produced by different manufacturers,the development of electric field standard devices has become particularly important.To meet the calibration requirements of low-frequency,high-fieldstrength electric field probes,a low-frequency electric field standard device was developed using the parallel plate method.The device consists of two square aluminum plates with a side length of 1 m and a plate spacing of 0.5 m.The frequency range is DC to 10 kHz,with an electric field strength range of 0 to 3000 V/m.Through theoretical analysis,software simulation,and experimental measurements,the effects of edge effects,plate material,structure shape,operating frequency,and other factors on the standard electric field generated by parallel plates were studied,and an uncertainty evaluation was conducted.A new measurement model was proposed,and uncertainty components caused by seven factors were evaluated separately:plate voltage,plate spacing,field uniformity within the parallel plates,probe fixture,probe alignment,finite size of parallel plates,and probe influence.The resulting expanded uncertainty is U=6.8%(k=2).The results show that the developed electric field standard device can meet the calibration requirements for low-frequency electric field probes.