永磁直驱风电系统低电压运行特性的分析

通过构建永磁直驱风电系统的仿真模型,实现网侧变换器输出有功和无功功率的解耦控制,增加卸荷负载以提高其应对电压跌落等故障的穿越能力,对风电系统运行在单位功率因数、超前和滞后功率因数情况下的跌落特性进行了仿真分析,讨论了电压跌落期间风电系统对电网的无功支持.仿真结果表明,直驱式永磁同步电机风电系统具有较强的低电压穿越能力,可以安全运行在不同功率因数下,同时能在电网电压故障期间对系统提供一定的无功支持.

Analysis on the Low-voltage-ride-through Capability of Direct-drive Permanent Magnetic Generator Wind Turbines

A direct driven permanent magnetic generator wind turbine utilizes a decoupled control on the active and reactive power in its grid-side converter.Its capability of low voltage ride through(LVRT)can be improved by shedding loads during the voltage sag period.A model is developed and used to simulate the wind turbine's performance during voltage dips with a unity,a leading and a lagging power factor respectively.The reactive power support of wind turbine to the main system during voltage dips is discussed.Simulation results indicate the wind turbine capability of LVRT,reactive power support with various power factors during grid faults.