STATCOM在双馈风电场低电压穿越中的应用研究

摘要

双馈感应发电机( DFIG)采用转子撬棒( Crowbar)进行低电压穿越保护时，须向电网吸收大量的无功功率，不利于故障过程中电网电压恢复。文中在双馈风电场中加入静止同步补偿器( STATCOM)，用以补偿Crowbar动作后DFIG异步运行时对电网的无功需求。通过不同程度电压跌落下风电场动态仿真进行验证，结果表明电网电压跌落严重时STATCOM的无功补偿效果明显，电网故障中DFIG还能向电网提供一定出力，维持电网稳定运行；与只投入Crowbar的情况相比，同时加入STATCOM和Crowbar不会对DFIG各分量产生冲击；电压跌落轻微时DFIG可通过自身的变流器调节实现低电压穿越，投入Crowbar和STATCOM反而会加剧系统的振荡。%Doubly fed induction generator ( DFIG) uses a rotor crowbar ( Crowbar) for low voltage ride through protection,and needs to absorbe considerable reactive power from grid, which is not conducive to the grid fault restoration process. In this paper, the STATCOM are added to the wind farm with DFIG,and it is used for satisfying the DFIG�S demand of reactive power from the power grid after the start the Crowbar circuit. According to the dynamic response of the DFIG in different degree of voltage drop simulation results, the effect of STATCOM on reactive power compensation is obvious and DFIG can provide amount active power to the grid when the grid voltage drops seriously. Compared with the crowbar circuit, adding STATCOM device and Crowbar circuit do not have an impact on DFIG� components. when the voltage drop isn�t so serious, DFIG can achieve low voltage ride through by it�s own low voltage ride through capability, and external crowbar circuit and STATCOM device can increases system�s oscillatory.