Abstract: The operation status of crowbar and chopper protection during low voltage ride through (LVRT) has a significant impact on transient response characteristics of doubly fed induction generator (DFIG) wind turbines. However, the traditional equivalent methods can only identify and characterize the operation and transient characteristics of crowbar protection, which will cause equivalent errors when wind farms equipped with two types of protection, making it difficult to accurately describe the dynamic characteristics and action patterns of wind power from the grid side. Such errors will be amplified in high penetration wind power scenarios, and may have an impact on the security and stability analysis of the power system in severe cases. Therefore, this paper fully considers DFIG control strategy during fault ride through, explores the cooperative action characteristics of crowbar and chopper during low voltage ride through, proposes a universal equivalent method for doubly fed wind farms, and verifies the correctness of the theoretical analysis through MATLAB/Simulink. Compared with the equivalent method that only considers Crowbar protection, the proposed method shows higher accuracy.