Study of DFIG wind turbine fault ride-through according to the Danish grid code

This paper presents a new decentralized control strategy to enable a Doubly-fed Induction generator wind turbine, DFIG WT, to fulfill the Danish grid code requirements during different perturbations. A nonlinear controller is adopted for the grid side converter, GSC, to ensure decoupled control of the DC link voltage and the reactive power, and counteract the DC link voltage runaway. Moreover, the GSC is dedicated to inject more reactive power during voltage dips to satisfy the grid code reactive power support obligation. A conventional PI controller is devoted to control the rotor side converter, RSC, with additional compensation terms to reduce the rotor over-speed, and limit the rotor and stator large transient currents. A diverse set of symmetrical and asymmetrical voltage excursions are investigated to evaluate the effectiveness of the proposed method using MATLAB/SIMULINK environment. The obtained results assure the capability of the proposed control strategy to satisfy the Danish grid code requirements.