Permanent magnet synchronous generator offshore wind farms connected to a single power converter

The paper deals with permanent magnet synchronous generators based wind farms connected to a single power HVDC-VSC converter. A control scheme is proposed and validated by means of simulations. The proposed control scheme needs only current and voltage measurements in the wind farm transformer and seeks the maximum power generation using a variable frequency offshore grid, provided by the HVDC-VSC. The work includes an evaluation of the power generated by variable and constant frequency offshore wind farms. Results show that a significant power increase of more than 20 % can be obtained by applying the appropriate variable frequency in a certain wind farm. The case study considers a wind farm composed of four wind turbines based on permanent magnet synchronous generators.