A novel thyristor rectifier for series connection of wind turbines

According to recent studies by 2020 a share of almost 12% of the worldwide electricity demand will be provided by the wind. Offshore wind farms are expected to have a significant growth to meet these targets, but higher procurement and operating costs are still limiting factors for their development. Several configurations based on internal DC collection have been proposed with the aim of reducing costs. Within these schemes, an attractive concept is the series connection of a sufficiently high number of turbine units to allow HVDC transmission without an offshore substation. The paper presents a novel rectifier topology for the series connection of turbine units containing only diodes and thyristors in order to combine low cost, high converter efficiency and high reliability.