保护用电流互感器饱和特性及其误差曲线研究

当电力系统发生故障时,一次电流比正常运行时的电流大几倍甚至几十倍,此时,保护用电流互感器的铁芯发生饱和,引起二次电流的畸变,从而使继电保护及其二次设备误动作。笔者对保护用电流互感器的误差与饱和特性进行了分析,介绍了实际工作中电流互感器误差曲线的绘制以及二次负载的校核方法,并提出了减小电流互感器误差的具体措施。

Research on Saturated Characteristics and Error Curve of Protective Current Transformer

The primary current of power system may increase several or even multiple times while power system faults occur.In this condition,the iron core of protective current transformer will become saturated,which causes the distortion of secondary current and affects the operation of protection relay and other secondary equipments.In this paper,the saturated characteristics of protection current transformer are analyzed,the methods of plotting error curve and checking secondary load are introduced,and the measure of reducing error for protection current transformer is presented.