The calculation of short circuit current is an important foundation for fault analysis of power system integrated into distributed generation. Firstly, the transient characteristics of induction generator (IG) are investigated, and the analytic formula of its stator current under three-phase short circuit in distribution network is derived making use of the steady-state equivalent circuit of IG. Then the three-phase short circuit currents of IG are compared and discussed when the short circuit occurs near to and far from it. Subsequently, according to the characteristic of forced component proportion between stator flux and rotor flux of IG, the impacts of its rotor speed on direct-current and periodic components are studied. Finally, an evaluation method to determine the current peak of three-phase short circuit for induction generator in distribution grid is proposed based on the change law of IG rotor speed under the grid fault. The correctness of the proposed method is verified by the fifth electromagnetic transient model of IG in PSCAD/EMTDC simulation software. This work is supported by National Natural Science Foundation of China (No. 51277184).%短路电流计算是分布式发电接入配网规划和保护的基础。研究感应发电机(IG)的故障暂态特性，利用 IG 静态等值电路推导出配网三相短路时其定子短路电流的解析表达式，进而比较配网近端和远端短路情况下的IG三相短路电流，分析IG转子和定子磁链强制分量比例系数特性，研究 IG 转速变化对其短路电流直流分量和周期分量的影响。根据配网短路故障后IG转速的变化规律，提出IG接入配网的三相短路电流峰值评估方法。采用PSCAD/EMTDC仿真软件中IG的5阶动态模型仿真验证了该方法的正确性。
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