直流分流器电阻测量结果的不确定度评定

Uncertainty Evaluation of Resistance Measurement Results of DC Shunt

测量不确定度是直流分流器校准的一项重要内容。但实际校准过程中经常会因为测量模型不准确、不确定度传播率计算错误、不确定度分量考虑不全面和不确定度分量重复计算等原因而导致无法得到较为准确、客观的不确定度。分别介绍了使用直流标准源法、标准分流器法、直流电流比较器法和直流电阻电桥法校准直流分流器电阻参数时的不确定度评定过程,并给出了各校准方法下的测量模型、不确定度传播率、不确定度来源,以及各不确定度分量、合成标准不确定度和扩展不确定度的计算方法,以期对相关人员有所帮助。

Uncertainty of measurement is an important parameter for calibrating DC shunts.However,in the actual calibration process,it is often impossible to obtain a more accurate and objective uncertainty due to inaccurate measurement model,incorrect calculation of uncertainty propagation rate,incomplete consideration of uncertainty components and repeated calculation of uncertainty component.The uncertainty evaluation process when calibrating resistance parameters of DC shunt by using standard source method,standard shunt method,DC current comparator method and DC resistance bridge method is introduced,and measurement model,propagation rate of uncertainty,the source of uncertainty,the calculation method of each component of uncertainty,the synthetic standard uncertainty and extended uncertainty are introduced under each calibration method in order to be helpful to relevant personnel.