基于变压器功率因数对励磁涌流和内部故障电流的识别

针对变压器采用纵差动保护会受到励磁涌流的影响而误动作,以及励磁涌流和内部故障时的短路电流的区分问题,提出一种根据变压器两侧三相瞬时功率因数的变化关系来识别励磁涌流和内部故障的方法.该方法简单、便捷,从能量的角度进一步揭示了变压器励磁涌流与内部故障电流本质不同.

Discrimination between Inrush Current and Internal Fault Current by Power Factor

The discrimination between internal fault current and inrush current in transformer is very difficult in transformer protection.This paper proposed a new algorithm based on the theory of instantaneous reactive power for the discrimination between internal fault current and inrush current of transformer protection.This algorithm was mainly based on the power factor of instantaneous active power and the instantaneous reactive power.The advantages is simple and convenient,moreover,of revealing the differences ...