永磁直驱风电机组的低电压穿越控制策略

Control strategy for low voltage ride-though of direct-drive permanent magnet wind power generator

通过对直驱式永磁同步风力发电机(PMSG)系统的研究,针对电网对无功控制和低电压穿越能力的技术要求,提出了一种改进型控制方法,该方法通过永磁直驱风电机组机侧变流器改变发电机负载转矩实现最大风能利用,配合直流侧卸荷电路的条件下,在深度电网故障时,通过网侧变流器运行于无功优先输出模式的控制策略与网侧增加的新型无功补偿电路结合,通过控制可关断器件的通断,实现快速平滑调节电网的无功,提高风电系统的低电压穿越能力。仿真结果表明所提出方案有效提高了PMSG系统的无功补偿和低电压穿越能力。

According to the technical requirements for the reactive power control and low-voltage ride-through （LVRT）, an improved control method was proposed through analyzing the wind turbine with a direct-driven permanent magnet synchronous generator （PMSG）. The generator load torque was changed by the machine converter to achieve maximum utilization of wind energy. At a depth of power failure, with unloading circuit corndition under the DC side, by controlling lhe tum-off device on and off, the network-side converter operating in reaclive mode conkol strategy priorities and the new reactive power compensation circuit at the network-side were combined to achieve fast and smooth adjuslmerd of reactive power. Simulation results show that the readive power compertsation of PMSG systems and low-voltage ride-through capability are effectively improved.