For analyzing doubly-fed wind power generation system and its operation characteristics in power grid accurately, its electromechanical transient models are developed. The mathematical model and pitch angle control model are established for components of doubly-fed wind power generation system including the wind turbine, mechanical device and doubly-fed induction generator. Based on its electrical-magnetic model, the models of converters control system of rotor and network sides are obtained, considering electromechanical operation characteristics. On this basis, the user defined (UD) models of doubly-fed wind power generation system in PSASP are constructed. The UD models are applied in the single machine infinite bus system for simulation. The results show that the models developed can reflect the transient characteristics of the system.