Fault ride-through capability improvement of wind farms using doubly fed induction generator

This paper presents a doubly fed induction generator in a sample distribution betwork. Grid consist of two distributed generation (DG) units. DG1 is a 5MVA synchronous generator with its excited and governor systems. DG2 is a doubly fed induction generator wind turbine which encompasses a wound rotor induction generator and a partial scale power electronic converter as grid side and rotor side converter. Simulation is performed in PSCAD/EMTDC software. The objective is to keep DFIG connected to the grid in abnormal conditions which is called fault ride-through capability. An active diode bridge crowbar switch is proposed and effects of its parameters in dynamic response of DFIG are investigated. Simulation results show well defined parameters of crowbar maintain stability of DFIG and improve its fault ride-through capability.