一种确定电流互感器在任意负荷下的误差计算方法

A calculation method of determining current transformer error under any burden

电流互感器的误差并非恒定不变,一般与二次负荷和一次工作电流有关。检定证书出具的是上下限负荷下的误差数据,无法知道在特定负荷点下的误差数值。通过计算给出了在已知这上下限负荷误差数据的条件下,确定任意负荷点下误差的计算方法,并通过实验验证了理论计算的准确性。结果表明,通过理论计算得到的值与实测值的偏差小于该准确度等级的两个修约间隔。因此,推导的任意负荷点下误差的计算方法能在实际工作中应用。

The error of current transformer is not constant, which is related to secondary burden and primary working current. Verification certificate shows the error data of current transformer at rated burden and lower limit burden. Therefore, error at specific burden is unavailable. This paper presents error calculation method at any burden under the condition of known error data at rated burden and lower limit burden. Meanwhile, it is verified the correctness of theoretical calculation through experiment. The result shows that the error between calculated value and measured val- ue is less than two rounding intervals at class 0.2. Thus, calculation method of error at any burden deduced in this paper can be applied in the practical work.