A Study of Fault Characteristics of Doubly-fed Wind Power Generation System

In view of the complex transient characteristics of wind power plants caused by the coupling of electromagnetic transient of motor and converter regulation process after power grid failure, a calculation method of DFIG short circuit current with or without crowbar is proposed. First, the fault equivalent network which takes the rotor converter control into account is established. On this basis, considering the transient regulation of the grid-side and rotor-side converters, the expression of the stator and rotor short-circuit current under the fault of the power grid is derived. RTDS wind farm simulation results verify the correctness of the derived expressions and related theories.