为解决现有“三分量”频率框架的短路电流分析方法无法全面刻画短路电流耦合频移特征的问题，研究建立了一种能够显式刻画定转子耦合频移效应的分析方法，以提高大规模风电场故障条件下短路电流的计算精度。该方法以机内转子电动势作为统一中间变量，将撬棒投入、转子侧变流器闭锁/再投入及励磁限幅等不同故障穿越策略下的转子侧暂态行为映射至同一状态空间中，从而解决分阶段计算过程中非零初始状态导致的动态不连续问题。之后在此基础上建立穿越过程中定子电压与定、转子电流之间的统一传递函数关系，并进一步推导控制策略切换引入的额外本征极点，从机理上揭示了转差分量与工频分量在多阶段控制作用下发生频移并形成多频耦合分量的内在原因。同时采用与转子侧一致的建模思路，建立网侧变流器与定子电压在不同控制策略下的统一传递函数关系，从频域角度揭示了短路电流中还存在受网侧变流器控制影响的附加谐波分量。最终算例结果表明，在实际故障穿越场景下，该方法大幅降低现有“三分量”框架的最大计算误差，在轻微电压暂降条件下保持在2.2%以内，而在严重电压暂降情况下保持在2.8%以内，表现出良好的鲁棒性与适应性。同时，相关谐波分量分解结果有效说明了理论分析中多频耦合分量的存在，并基于此有效解释相量放大引起的继电保护误动机理。研究结果为提升大规模风电系统故障分析精度，将定转子频率耦合效应与多阶段控制切换过程统一纳入故障电流计算框架，实现了对不同复杂条件下故障电流的快速、精确求解。

To address the limitation that the existing “three-component” frequency framework for short-circuit current calculation analysis cannot fully characterize the dynamic features of frequency coupling and shifting, an analysis approach explicitly capturing the stator–rotor coupling frequency shift effect is developed to improve the calculation accuracy of DFIG short-circuit currents under large-scale wind farm fault conditions. The method employs the internal rotor electromotive force as an unified intermediate variable to map the rotor-side transient behaviors (e.g., crowbar activation, rotor-side converter blocking/re-activation, excitation limiting) under different fault ride-through strategies into a unified state space, thereby resolving the dynamic discontinuity problem caused by non-zero initial states in the phased calculation process. On this basis, a unified transfer function relationship between stator voltage, stator current and rotor current during the ride-through process is established, and additional eigen poles introduced by control strategy switching are further derived to reveal the intrinsic mechanism of frequency shift of slip components and power frequency components under multi-stage control actions, which form multi-frequency coupled components. Meanwhile, following the same modeling idea as the rotor side, a unified transfer function relationship between the grid-side converter and stator voltage under different control strategies is established, revealing the additional harmonic components in the short-circuit current affected by the grid-side converter control from the frequency domain perspective. Case studies demonstrate that the proposed approach reduces the maximum error of the existing "three-component" framework, which is kept within 2.2% under shallow voltage sags and within 2.8% under severe voltage sags, exhibiting excellent robustness and adaptability. Meanwhile, the relevant harmonic component decomposition results effectively verify the existence of multi-frequency coupled components in the theoretical analysis, and based on this, effectively explain the relay maloperation mechanism caused by phasor amplification. The findings provide a theoretical basis for enhancing the accuracy of fault analysis in large-scale wind power systems, integrating stator–rotor frequency coupling effects and multi-stage control switching into a unified short-circuit current calculation framework, thereby achieving fast and accurate solutions under various complex fault conditions.