基于预充磁原理的三相变压器励磁涌流抑制

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关键词：三相变压器；空载合闸；励磁涌流；剩磁；充磁

DOI：10.15938/j. emc.2025.06.002

中图分类号：TM406 文献标志码：A 文章编号：1007-449X（2025）06-0012-10

Suppression of inrush current of three-phase transformer based on pre-magnetization principle

WU Yucai 1 ，LIU Yanze¹， TAN Yaokun1， ZHANG Shaojiu²， JIANG Yi² HUANG Chenhui²，LI Yingfeng³， ZHANG Zhiming³

（1.DepartofElectricalEnginering，NorthChinaElectricPowerUniversity，BaodingO71OO3，China；2.FujianFuqing Nuclear

PowerCo.，Ltd.，Fuqing350318，China；3.BaodingYingdianElectric PowerTechnologyCo.，Ltd.，Baoding O71003，China）

Abstract：Excitation inrush current can not only cause misoperation of transformer differential protection， but also cause tripping of nearby normally operating equipments such as transformers and motors. Effective suppression of excitation inrush current is of great significance. The expression of the main magnetic flux was derived in the core during the no-load closing process of the transformer. It is found that the residual magnetism of the core to some extent affects the amplitude of the free component in the magnetic flux expression. When the magnitude and direction of the residual magnetism are appropriate，the free component of the magnetic flux can be completely eliminated，thereby reducing the excitation inrush current of the no-load closing to zero. Subsequently， simulation verification was conducted on a 500kV three-phase double winding transformer group，and further experimental verification was completed on a 15kVA three-phase autotransformer group，demonstrating that pre magnetization of the core can significantly reduce the excitation inrush current during the no-load closing process of the transformer. This method not only helps prevent misoperation of diffrential protection but also significantly reduces the risk of nearby equipment tripping.

Keywords：three-phase transformer； no-load closing； excitation inrush current； remanence； magnetiza-tion

0引言

由于变压器主磁通不能突变，在空载合闸充磁过程中，其铁心磁通中将产生自由分量，该分量与稳态分量相叠加，导致铁心出现过饱和现象，考虑到铁心材料的非线性饱和特性[1]，在饱和时段将产生极大的励磁电流，称其为励磁涌流[2-3]。（剩余14666字）