电网故障下直驱永磁风力发电机组机侧变流器改进控制策略

Low voltage ride through of directly drive permanent magnet synchronous generator (DPMSG) with the grid voltage sags was presented, in order to enhance operational capability of DPMSG during grid failures. Firstly, the control strategy of maximum wind-power tracking of machine-side converter was analyzed and better tactics was proposed. By changing maximum wind-power tracking parameter generator output power was reduced, so that the power between machine-side converter and grid-side converter was balanced and the DC-bus voltage swell was restrained under grid voltage sags. The results show that the wind turbine has the low voltage ride through capability defined in the grid code in the case of no additional discharge energy circuit. Simulation demonstrates the correctness and practicability of the proposed method.