波形比较法变压器差动保护原理

本文提出了一种变压器差动保护的新原理，该原理的思路是：通过面积比较的方法，将测量到的一周波变压器差流分成两段等长度的波形，由这两段波形的相关系数和方差构成鉴别励磁涌流的判据。该原理在本质上是涌流波形的形状，大小和变化率等多种特征征量的综合鉴别，仿真计算和模拟试验的结果表明，本文的原理可以采用分相制动，能够快速切除合闸时的内部故障，并且受ＣＴ饱和的影响小，因而兼有二次谐波制动原理和间断角原理的优点，

The Principle of Transformer Differential Protection Based on Wave Comparison

A new principle of transformer differential protection is presented in this paper.According to comparing the area,the wave of the transformer differential current can be divided to two parts.Based on their correlation and covariance,the criterion to distinguishing magnetizing inrush is made up.Computer emulation and dynamic simulation show,the protection can clear the close onto fault quickly and don not influenced by CT saturation.The protection action time is less than 15ms.