Modeling and implementation of direct-drive permanent magnet wind turbine based on generator parameter conversion

Accurate wind turbine model is the basis of studying its dynamic physical process and performance characteristics. In order to resolve the difficulties in modeling direct-drive permanent magnet wind turbine (DD-PMWT) because of the absence of permanent magnet synchronous generator (PMSG) model in some existing power system analysis software, the method to interconversion between electrical excitation synchronous generator (EESG) and PMSG was presented as well as the parameter conversion formulas and procedure were provided on the basis of their mathematical model and equivalent circuit in this paper. In additon, the model of DD-PMWT was built in DIgSILENT PowerFactory by means of replacing PMSG with EESG. Finally, based on the typical test system provided by Western Electricity Coordinating Council (WECC), the dynamic characteristics of DD-PMWT were analyzed. The simulation results verified the validity of the proposed method and the rationality of the established DD-PMWT model.