Power control of series connected passive-active rectifiers for a dual-star PMS wind generator

In this paper, a hybrid topology of series-connected passive-active rectifiers is proposed for offshore wind energy conversion systems (WECSs). In particular a combined structure of a voltage-source converter (VSC) and a diode rectifier (DR) is connected to a double-star permanent magnet synchronous generator (2S-PMSG) reducing cost and losses. Nonetheless, the current harmonics due to diodes behavior are mitigated without using large AC filters using an appropriate control structure. The VSC is downsized compared to a fully active rectifier stage. The potential benefits of this hybrid topology include low power losses, low costs, and smaller footprint resulting from diode-based component. The simulation results for 20 kW generation system are shown to verify the effectiveness of the proposed approach and the control method.