基于参考电流增量法的感应分流器校验方法

Calibration of inductive current divider based on reference current increment method

感应分流器具有高准确度和高稳定性的电流比例,在电流互感器检定领域有着广泛的应用。文中提出了一种基于参考电流增量法原理的感应式分流器校验方法,文中介绍了参考电流增量法的基本原理;分析了参考电流互感器和差值电流测量线路的设计原理;搭建了感应分流器自校验的实验线路;对研制的双级感应分流器在50 Hz~1 kHz频率范围进行了校验,并对校验结果进行了不确定度分析。实验结果表明,在50 Hz~1 kHz频率范围内,双级感应分流器比值差测量合成标准不确定度优于5×10^(-8) A/A,相位差测量合成标准不确定度优于1×10^(-7) rad。

Inductive current divider has high accuracy and high stability of current ratio,which is widely used in the verification of current transformer and other fields.In this paper,a method for calibrating inductive current divider based on the principle of reference current increment method is proposed,and the basic principle of reference current increment method is introduced;the design principles of reference current transformer and differential current measurement circuit are analyzed;the experimental circuit for the self-calibration of the inductive current divider is built;the developed two-stage inductive current divider is calibrated in the frequency range of 50 Hz~1 kHz,and the uncertainty of the calibration result is analyzed.The experimental results show that,in the frequency range of 50 Hz~1 kHz,the measurement synthetic standard uncertainty of the ratio difference of the two-stage inductive current divider is better than 5×10^(-8) A/A,and the measurement synthetic standard uncertainty of the phase difference is better than 1×10^(-7) rad.