Control of a doubly-fed induction generator in wind park during and after line-voltage distortion

Doubly-fed induction generator (DFIG), as a wind generator, is economically justified, but control of the machine is difficult. In addition, it is significantly difficult to assure continuous operation of the DFIG during and after line-voltage distortions, as required by grid code. Nowadays, there is no single used method; the problem is not entirely solved. In the paper, not only features of the doubly-fed machine during and after line-voltage distortions, but also proposal of the new control system structure based on sliding-mode control is presented.