变压器一次接线组别对二次差动保护接线方式的影响

Influence of the Primary Wiring Connection Mode of Transformer on the Connection Mode of Secondary Differential Protection

针对一起Y/d-11接线组别的变压器差动保护二次误接线进行分析。变压器Y侧一次绕组电压相位与d侧一次绕组电压相位存在相角差,导致变压器两侧一次电流存在相角差。因此参照d侧一次绕组的联结方式对差动保护的Y侧电流互感器二次绕组进行三角形变换,以消除一次相角差的影响,保证差动保护的二次接线方式正确。

Analysis is carried out based on a misconnection fault of secondary differential protection of Y/d-ll wiring category transformer. It is found that there is a vector difference between the voltage of Y-side primary winding and that of the d-side. Therefore, there is a current difference between the two sides of transformer. For this reason, a starlike transformation is carried out to the secondary winding of Y-side current transformer according to the connection mode of d-side primary winding, in order to eliminate the influence of the vector difference and to ensure the correctness of secondary differential protection.