全光纤电流互感器受导体偏心影响的机理

针对全光纤电流互感器受导体偏心影响的问题,在光学电流互感器传感部分的分布参数模型的基础上,建立了与之对应的全光纤电流互感器传感环分布参数模型。基于传感环的分布参数模型提出了全光纤电流互感器受导体偏心影响的产生机理,该机理揭示了全光纤电流互感器受到导体偏心影响的原因,即为传感光纤中的线性双折射和传感环上不均匀磁场的共同作用。同时,分析了被测导体偏心对测量准确度的影响,得出偏心只会影响全光纤电流互感器比差的大小而不会影响线性度的结论。实验结果与理论分析一致,表明所提出的理论和结论的正确性。

Influence Mechanism of Conductor Eccentricity on All-fiber Optic Current Transformers

In view of the influence of conductor eccentricity on the all-fiber optic current transformers (FOCTs), the corresponding distributed parameter model for the sensing coils of FOCTs is developed based on the distributed parameter model for sensor sections of optic current transformers. Based on the distributed parameter model of sensing coils, the influence mechanism of conductor eccentricity on FOCTs is proposed. The mechanism reveals the reasons for leading to the eccentricity problem of FOCT, i.e., the combined effect of sensing fiber linear birefringence and nonuniform magnetic field on the sensing coil. The influence of measured conductor eccentricity on the measuring accuracy is analyzed. The conclusion that the eccentricity could only influence the ratio error of FOCT instead of linearity is obtained. The results of theoretical analysis are in agreement with experimental results, which shows the correctness of the theory and conclusion proposed. This work is supported by Heilongjiang Provincial Natural Science Foundation of China (No. E201237) and Fundamental Research Funds for the Central Universities (No. HIT.NSRIF.2013018).