数值拟合提高磁电系电表精度

磁电系电表的改装、扩程实验,通常采用串联分压电阻或并联分流电阻的方法。扩程电阻的阻值确定一般先通过理论计算,再通过实验进行满量程修正。实验中发现这样改装的电表偏差较大,在起始与满量程处误差较小,中间部分的误差随不同的电表或正或负,随机分布在X轴的两侧,由于大部分误差曲线对于X轴是不对称的,因而大部分电表的精度还能再提高。通过对改装、扩程的磁电式电表的误差曲线进行分析,采用数值拟合修正的方法,让扩程电阻同时充当精度调节电阻,改善校准曲线的分布,可以在原有基础上大幅提高电表的整体精度,甚至提高电表的等级。

Numerical Imitation Improving Accuracy of the Magnetoelectric Ammeter

The range-enlarging experiment of magnetoelectric ammeter is always realized by means of the split-pressure of resistance in the series connection and the split-flow of resistance in the parallel connection.However,the error and the calibrating curve unsymmetrical with the x axis are often found in the experiment,so the accuracy class of many ammeters could be improved.With the numerical imitating correction of refitting ammeter,the authors can make the calibrate curve better,and improve the accuracy class of ammeter.