直流电流传感器高精度校准系统设计

Design of High-precision Calibration System for Direct Current-current Transformer

直流电流传感器(DCCT)的测量精度是高精度直流稳流电源输出电流精度的关键影响因素之一。针对DCCT优于1×10^-5的电流测量精度,本文提出了一种通过用高准确度的直流比较仪(DCC)测量电阻原理设计的校准系统,可实现DCCT 0~400 A测量范围内的高精度校准,且在整个校准范围内系统测量的相对不确定度优于1.1 ppm。通过实验测试DCCT的准确度和线性度验证了整个校准系统的精度,为进一步提高磁铁电源的电流精度提供了保障。

The measurement accuracy of direct current-current transformer(DCCT) is one of the key factors influencing the output of high-precision direct current power supply. For the DCCT measurement accuracy is better than 1×10^-5, a calibration system designed by measuring resistance principle with a high accuracy direct current comparator(DCC) was presented. The system can achieve high-precision calibration of DCCT within the measurement range of 0-400 A, and the relative uncertainty of the system calibration is better than 1.1 ppm in the whole range. The accuracy and linearity of DCCT were tested to verify the accuracy of the whole calibration system, which can improve the current accuracy of the magnet power supply in the future.