Power system transient stability enhancement using direct drive wind generators

Recent grid codes requires the wind farms not only to ride through the fault disturbances but also support the stability of nearby grid during severe network disturbances. This paper presents the impact of direct drive wind generators to the improvement of fault ride through (FRT) capability of fixed speed wind turbine. Three operational strategies have been investigated, i.e. without reactive power support, considering reactive power support complying with the Danish grid codes (with and without considering overloading of the converter currents). The proposed control strategies enable the direct drive wind generators to inject the required reactive power in order to help stabilizing the nearby fixed speed wind generators during faults. Simulation studies are carried out by using MATLAB/SIMULINK.