风力机等效模型对双馈风机LVRT特性影响研究

The Influence of Wind Turbine Equivalent Model on the LVRT Performance of DFIG

风电机组单机并网容量逐步增大,为了较准确的研究风力机等效模型对双馈风力发电机组低电压穿越特性的影响,本文采用等效集中质量法,建立了同时考虑风力机叶片和传动轴柔性的风力机三质量块等效模型,以及考虑传动轴柔性的两质量块等效模型和忽略风力机柔性的单质量块等效模型。依据并网导则要求,建立了基于Crowbar电路的双馈风力发电机组低电压穿越控制策略。在电网电压不同跌落故障情况下,研究了采用不同风力机等效模型对双馈风力发电机组低电压穿越特性的影响。仿真结果表明:同时考虑风力机叶片和传动轴柔性的风力机三质量块模型更能准确地反映双馈风力发电机组低电压穿越有功功率特性。

In order to study the influence of wind turbine e- quivalent model on Double Fed Induction Generator （DFIG） Low Voltage Ride Through （LVRT） ability accurately, this paper uses equivalent lump mass method to establish 3 models： a wind turbine three-mass equivalent model considering the flexibility of wind turbine blade and drive shaft, a twomass equivalent model only considering drive shaft flexibility and a one-mass equivalent model ignoring wind turbine flexibility. According to LVRT control strategy of DFIG based on Crowbar protection circuit, this paper analyzes the impact of different wind turbine equivalent models on LVRT performance of DFIG with different gird voltage dips. The simulation results show that the three equivalent mass models of wind turbine, considering the flexibility of wind turbine blade and drive train, can reflect LVRT performance of DFIG more accurately.