永磁直驱风电系统的低电压穿越控制策略

Direct-drive Permanent-magnet Wind Power System Control Strategy for Low Voltage Ride Through

为了提高直驱式永磁同步风力发电机(D-PMSG)低电压穿越能力,在分析D-PMSG和全功率变流器数学模型的基础上,采用了一种改进的变流器控制策略,将发电机等效为电网,用机侧变流器控制直流母线电压和定子电压稳定,网侧变流器控制有功功率和无功功率。该策略使系统能在电网电压跌落故障时,保持母线电压稳定、抑制2倍工频振荡,控制网侧电流快速恢复稳定,大大提高了风力发电系统的安全稳定性。实验验证了该策略的可行性和优越性。

The paper adopts an modified converter control strategy to improve the function of D-PMSG low voltage ride through based on the mathematical model analysis of D-PMSG ＆ full-scale converter.The strategy equals the genera- tor to power grid, uses the generator-side converter to control the UC-link voltage and the stator voltage stability, and the grid-side converter to control the active and reactive power.When the grid voltage encounters a sudden fallen breakdown, it can maintain the UC-Link voltage stable, depress 2 times oscillation on power frequency, restore stabi- lization of current on grid side.The feasibility and advantage of the presented strategy are verified by experiments.