A novel concept for offshore wind-power plant with DC collection system based on radial-connected converter topology

This paper investigates the use of a dc collection grid in offshore wind farm; the dc grid is built out by a 'radial connection of active rectifiers.' The proposed active rectifier topology consists of a three-phase half-controlled switch voltage source converter (VSC) cascaded with a single active bridge dc-dc converter. The proposed wind farm configuration is further compared to the recent development of a dc collection grid technology for wind farms. In fact, the majority of dc collection grids for wind farms are built out with the ring feeder configurations; also, most of the wind energy conversion units integrate the conventional full-bridge VSC. The comparison is done in terms of power loss, cost, voltage/current ripple, power factor, and control performance. Simulation results, using Power Simulator software, illustrate the performances obtained.