三相变压器和应涌流仿真建模分析

Model simulation and analysis for sympathetic inrush of three-phase transformer based on SIMULINK

变压器在空载投运过程中会导致相邻变压器出现和应涌流以及变压器继电保护误动作。在线性简化的基础上,建立了2台变压器并联和串联运行模型,运用2台并联变压器的磁链解析表达式和偏磁衰减规律,定性分析正在运行的变压器可能发生的饱和现象以及和应涌流的产生及影响机理;详细分析系统电抗、空投变压器剩磁、铁芯材料、接地方式等因素对和应涌流的影响;利用MATLAB/SIMULINK计算机仿真验证分析结论,为和应涌流导致变压器差动保护误动的分析以及认识和应涌流的本质奠定了基础。

The no - load running of a transformer may induce sympathetic inrush in neighbor transformer and relay protection misoperation of transformer. Based on linear simplification, parallel and serial models of 2 transformers are established, and by using analytical expression of magnetic flux and partial magnetic attenuation law of 2 parallel transformers, the possible saturation phenomenon of transformer in operation and occurrence mechanism and influence of sympathetic inrush are analyzed, especially the influences from system reactance, residual magnetism of no- load transformer, core material, grounding mode etc on satura- tion phenomenon are studied. The analysis conclusions are verified by computer simulation of MATLAB/SIMULINK and lay a foundation for misoperation analysis of transformer differential protection resulting by sympathetic inrush and understanding the essence of sympathetic inrush.