中文摘要：

在地磁暴影响下的高铁牵引供电系统中会产生地磁感应电流（GIC）, G IC能够造成自耦变压器直流偏磁,可能影响 供电系统的安全运行.为研究地磁暴对高铁自耦变压器非线性动力学特性的影响,分析 GIC侵害高铁供电系统中自耦变压 器的机理,给出变压器在偏磁作用下的磁化特性表达式,建立自耦变压器电路模型来分析GIC对自耦变压器的影响.经进 一步研究发现：自耦变压器电压是否发生混沌振荡与铁芯的磁化特性有关,非线性磁化特性指数《越大,GIC造成自耦变压 器电压混沌振荡的可能性也越大.

英文摘要：

Geomagnetically induced currents （GIC）, which may cause autotransformer DC magnetic bias, will be produced in high-speed railway traction power supply system under the influence of geomagnetic storms and affects the safe operation of power supply system. In order to study the effects of geomagnetic storms on nonlinear dynamic characteristics of autotransformer in high-speed railway, the mechanism of GIC intruding into the high-speed railway power supply system was analyzed and the magnetization characteristic expression of the transformer under the action of magnetic bias was presented. This paper established the circuit model with autotransformer, which was analyzed to study the effects of GIC on autotransformer. The further study shows that the chaotic oscillation of autotransformer voltage is related to the magnetization characteristic of the iron core. The greater the nonlinear magnetization characteristic index n, the more likely GIC is to cause the voltage chaotic oscillation in the autotransformer.