含不同机组风电场低电压穿越能力仿真研究

Simulation Study on Low Voltage Ride-through Capability of Wind Farms With Different Units

在PSCAD/EMTDC仿真环境下建立双馈风力发电场及恒速恒频风力发电场交流并网仿真模型,通过交流系统三相短路故障仿真,研究对比2种不同风力发电机组的低电压穿越能力。仿真得出恒速恒频风力发电机组避免飞车的极限切除时间,故障持续时间小于极限切除时间便可维持恒速恒频风力发电机组的稳定不脱网运行。通过在不同点设置短路故障对比得出,故障点距离风电场电气距离越远,风电场低电压穿越能力越强。

The simulation platform of wind farms with fixed speed induction wind turbines and doubly-fed induction wind turbines connected to the power grid was built in the electromagnetic transient simulation software PSCAD/EMTDC.Serious three-phase faults in the power grid were carried out to analyze the low voltage ride-through(LVRT)ability of various wind turbines.The research results show that wind farm’s LVRT ability with fixed speed induction wind turbines depends on the fault critical clearing time.When the fault clearing time is shorter than the fault critical clearing time,the wind farm with fixed speed induction wind turbines can have LVRT ability.Different points of faults simulations at power grid were carried out at the simulation platform.The research results show that wind farm’s LVRT ability depends on the electrical distance of the point of fault.The longer the electrical distance of the point of fault to the wind farm is,the stronger the wind farm’s LVRT ability.