基于单机等值与选择模态分析的风电场等值建模方法

随着风电接入电网容量的不断增加,风电接入对系统稳定性的影响愈发明显。因此构建合理的风电场并网模型对研究含风电场电力系统的动态特性具有重要意义。针对风电场的详细建模常常带来模型阶数过高、仿真时间过长等问题,提出了一种基于单机等值与选择模态分析的风电场等值建模方法。该建模方法首先对多台风机进行聚合等效,然后在单机等值聚合模型基础上,应用选择模态分析的方法,进一步降低模型阶数。数值仿真结果表明,该动态等值方法不仅可实现不同风速下多台风机的等值,还能够近似还原多风机系统原始的稳态与暂态行为,从而在风电场并网分析中可显著减小模型阶数,提高计算速度。

A wind farm equivalent modeling method based on single-machine equivalent modeling and selection modal analysis

With the increasing of penetration of wind power in the power grid,the impact of wind power on the system stability becomes more and more apparent.Constructing a suitable Double-Fed Induction Generator(DFIG)farm model is the basis for the dynamic study of wind power embedded system.A novel method,based on the single-machine aggregation method and Selection Modal Analysis(SMA),is proposed for the modeling of wind farms in this paper to solve some problems,such as high-order model and long time for simulation.Firstly,multi-DFIGs are aggregated as an equivalent single DFIG.Then,based on the aggregated model,the SMA method is applied to further reduce the model order.The numerical simulation results show that the dynamic equivalent method can not only realize the equivalent of multiple wind turbines under different wind speeds,but also can fit the steady and transient behavior of the system,which can simplify the model and thus improve the computational efficiency.