基于数字比较法的宽频标准电流互感器溯源技术研究

对于宽频标准电流互感器的校准，在50Hz附近的频段通常采用测差的方法，而在低至5Hz高至2.5kHz的频率下，由于标准器大都采用磁通门传感器的原理，无法与被检互感器的变比一一对应，因此必须采用同步采样的数字比较方法，本文通过对同轴分流器的宽频特性分析，设计了一种适合同轴分流器自校准的宽频互感器校验仪，以此完成对宽频标准电流互感器的误差校准，并采用多功能校准源与高精度数字万用表的配合实现分流器的校准和溯源。文章提供了完善的校准方案和详实的测试数据，并对各环节的校准不确定度进行了科学的分析，论证了校准方法的合理性和准确性，本方法对目前正在运行的浙江省电力公司20Hz示范性电网的计量工作有很大的实用意义。

Research on traceability technology of broadband standard current transformer based on digital comparison method

For the calibration of broadband standard current transformers, the method of measuring deviation is usually used in the frequency band near 50Hz. However, at frequencies as low as 5Hz and as high as 2.5kHz, due to the principle of using flux gate sensors in most standard transformers, it is not possible to correspond one-to-one with the transformation ratio of the tested transformer. Therefore, a synchronous sampling digital comparison method must be used. This article analyzes the broadband characteristics of coaxial shunts, A broadband transformer calibrator suitable for self calibration of coaxial splitters has been designed to achieve error calibration of broadband standard current transformers. The calibration and traceability of the splitter are achieved through the combination of a multifunctional calibration source and a high-precision digital multimeter. The article provides a comprehensive calibration plan and detailed test data, and conducts a scientific analysis of the calibration uncertainty in each link, demonstrating the rationality and accuracy of the calibration method. This method has great practical significance for the measurement work of the currently operating 20Hz demonstration power grid of Zhejiang Electric Power Company.