地磁暴影响下地磁感应电流(GIC)流过变压器中性点，引起变压器无功损耗增加，在强地磁暴环境中，系统的无功补偿装置可能过载，母线电压下降，可能引发连锁故障，继而导致大停电事故。对比事故链各环节特点和因磁暴导致的电力系统停电事故的发展规律，使用事故链模型来仿真实现地磁暴条件下的电网停电过程。基于自组织临界理论和非故障线路的安全稳定裕度来确定连锁故障的传播路径。结合IEEE-RTS79系统参数，估算各母线的地理位置，借助PowerWorld仿真软件，以该系统为例，研究结果验证了所提事故链模型可以反映给定电网条件下，地磁暴参数对电力系统事故链集与薄弱环节辨识的影响，研究结果可为量化和防治磁暴电网灾害提供依据。

In the condition of strong magnetic storm, geo-magnetically induced current(GIC) flowing through the neutral point of the transformer, causes the increase of reactive power loss of the transformer. This might lead to overload of the reactive power compensation device, drop of the bus voltage and occurrence of a chain fault, which in turn causes a blackout of the system. Comparing the characteristics of each link in the fault chain and the development law of the power system blackout caused by magnetic storms, the fault chain model is used to simulate the process of power outage under conditions of geomagnetic storm. The article determines the propagation path of cascading failures based on the self-organizing critical theory and the safety margin of non-faulty circuits. Combining the IEEE-RTS 79 system parameters, the geo-location of each bus is estimated. Taking this system as an example and using Power World simulator, the research results verify that the proposed model can reflect the geomagnetic storm parameters against the power system fault chains and the identification of weak links under given grid conditions. The research results can provide a basis for quantifying and preventing disasters in the magnetic storm condition.