基于负载率基尼系数的含风电电网健壮性分析

Robustness analysis of wind power grid based on the Gini coefficient of load ratio

风电场接入电网会改变网络结构和电网潮流的分布。文章引入负载率基尼系数的概念作为判断电网健壮性的指标,首先搭建含风电场的电网模型,模拟风电接入电网时的正常运行情况和电网发生随机断开时的情况,然后以IEEE30节点系统为例,通过分析风电场接入电网前后和接入不同节点时负载率基尼系数的变化,体现风电场接入电网环境后对电网健壮性的影响,并通过连锁故障模型证实了负载率基尼系数越大电网健壮性越差,最后根据连锁故障模型识别出关键线路,提出对电网健壮性改进的有效方法。

Wind farms continuously connect to the electricity grid, which changes the structure of grid and the distribution of power flow. In this paper, we introduce gini coefficient of load rate as an index to measure the robustness of the grid. Specifically, we first build a grid model simu- lating the cases where wind farms connect to the grid under the normal operating conditions and the random disconnected conditions. Then we analyze the change of gini coefficient of load rate when wind farm connects to the electricity grid and connects to different nodes using IEEE30 nodes system as an example. The analysis shows that whether wind farm connects to the grid does influence the robustness of the grid. We also confirmed that in OPA model the higher the gini coefficient of load rate, the worse the robustness of the network. Finally, according to the OPA model, we identify the key lines and proposed a corresponding effective method to improve the robustness of the grid.