Research on the Modeling of Leakage Magnetic Field and Short-Circuit Force of Power Transformer’s Short Circuit Fault

Abstract

近年来电力变压器短路故障频发，严重影响电网可靠运行，因此很有必要在理论上开展对电力变压器绕组的短路性能的研究。本文以一台较常见的三相三柱式独立绕组结构的220 kV电力变压器为例，在ANSYS中分别建立了变压器整体结构的二维轴对称和三维模型，计算变压器在三相对称短路情况下各绕组漏磁场和短路电动力，并进行对比分析，总结了漏磁密及电动力分布相应规律，同时与变压器现场吊包解体检查的结果作对比，验证了分析结果。本文的研究结论可为电力变压器短路故障研究提供一定参考。In recent years, the short-circuit fault of power transformer occurred frequently and seriously af-fected the reliable operation of power grid. So it is necessary to analyze the short circuit perfor-mance of transformer windings in theory. This paper has taken a three-phase three limb trans-former of 220 kV for an example, and the 2-D transient axisymmetric electromagnetic field and 3-D electromagnetic field are both studied by ANSYS. The leakage magnetic field and the short- circuit force in each winding are both calculated and analyzed during three-phase short circuit. Then the distribution rules of them are concluded. By comparing the results of transformer winding’s disintegration test, the analysis results are verified. The research conclusion may provide a reference to the analysis of the short-circuit fault of the power transformer.