Operation strategies for stability of gearless wind power generation systems

This paper proposes stable operation strategies for gearless wind power generation systems using permanent magnet synchronous generator (PMSG) under line fault. The proposed method uses a chopper circuit in DC-link circuit for gearless wind power generation system. This chopper circuit can avoid DC-link over-voltages under line fault. In addition, the control schemes in this paper include the maximum power point tracking (MPPT) control and a pitch angle control for the gearless wind turbine generator. By means of the proposed method, stable operation of wind power generation system under line fault becomes possible, and stable power supply from PMSG to the electrical power system after line fault clearing can be achieved immediately. The effectiveness of the proposed method is verified by computer simulations.