Control of DFIG wind turbines in offshore networks during large transients

Control flexibility and fault ride-through capability of offshore wind farms and their electrical collectors array have been studied in this paper. The research is focused on the implementation of different control techniques for large offshore wind farms and also for variable wind turbines. The third harmonic injection technique is added to improve the modulation signal, which is fitted into the PWM system. Improvements in the acquisition and process of the reference signal for the inner and outer current controllers have shown significantly power peaks’ reduction during large transients. Also, fault current reduction and reduction of the recovery time have been observed. The control system also improves considerably dc voltage performance in the HVDC link. Overall, results have shown significant improvements in the active and reactive power transmission for the ac star layout in the collector