考虑光伏随机性的交直流混合配电网鲁棒机会约束安全域模型

Robust Chance-constrained Security Region Model of AC/DC Hybrid Distribution Network Considering the Uncertainty of Photovoltaic Generation

为实现高比例光伏接入下交直流混合配电网的安全评估,构建了交直流混合配电网的鲁棒机会约束安全域模型。首先,提出一种基于区间划分的自适应带宽核密度估计方法,以获取光伏预测误差概率分布,构建光伏出力机会约束不确定集合;其次,采用功率与节点电压幅值比值为状态变量,在已有交流线性化潮流模型的基础上推导一种交直流混合配电网线性化潮流模型;然后,提出交直流混合配电网鲁棒机会约束安全域的概念和模型,结合列与约束生成算法和径向迭代搜索算法生成可观测的鲁棒机会约束安全域空间。最后,算例分析验证了所提模型能够在鲁棒机会约束安全域上准确、直观的反映光伏出力的随机性,进而为交直流混合配电网的准确安全评估提供支撑。

To realize the security evaluation of AC/DC hybrid distribution network with the high penetrations of photovoltaic generation,a robust chance-constrained security region model of AC/DC hybrid distribution network is constructed.First,an adaptive bandwidth kernel density estimation method based on the interval division is proposed,and the photovoltaic output chance-constrained uncertainty set is constructed based on the probability distribution of photovoltaic forecast error.Next,a linear branch power flow model for AC/DC hybrid distribution network is derived based on the AC linear power flow model by taking the ratio of power and node voltage amplitude as state variables.Then,the model of the robust chance-constrained security region of the AC/DC hybrid distribution network is developed,and the robust chance-constrainted security region boundary points are obtained based on the combination of the column and constraint generation algorithm and the radial iterative search algorithm.Consequently,the robust chance-constrained security region of AC-DC hybrid distribution networks is visualized.Finally,numerical results verify that the proposed model can accurately and intuitively reflect the randomness of photovoltaic generation in the robust chance-constrained security region,which positively contributes to the accurate security evaluation of the AC-DC hybrid distribution network.