考虑光伏出力相关性的主动配电网薄弱环节识别

Identification of Weak Link for Active Distribution Network Considering Correlation of Photovoltaic Output

随着大规模分布式光伏的接入,中低压配电网出现了电压越限、潮流反送等问题,为有效识别含分布式光伏配电网的薄弱环节,提出了考虑分布式光伏出力相关性的概率潮流计算,基于Copula理论和联合分布拒绝采样产生光伏出力相关场景,综合考虑网架状态薄弱和结构薄弱两方面特征建立评估指标体系,有效实现节点和线路的风险刻画。一方面,提出了基于改进重复潮流的主动配电网元件状态薄弱评估指标;另一方面,改进了主动配电网元件的结构薄弱性评估指标,并针对含大规模分布式光伏的配电网提出了基于最小二乘支持向量机的薄弱环节识别方法。最后,通过区域配电网实际数据和仿真算例验证了所提方法的有效性。

With the integration of large-scale distributed photovoltaic(PV),problems such as voltage violation and power flow inversion have emerged in the medium-and low-voltage distribution networks.In order to effectively identify the weak links of distribution networks containing distributed PV,a probabilistic power flow calculation method considering the correlation of distributed PV output is proposed.Based on Copula theory and jointly distribution rejection sampling,the scenarios related to PV output are generated.Considering the characteristics of status weakness and structure weakness,the evaluation index system is established,which effectively realizes the risk characterization of nodes and lines.On the one hand,the status weakness evaluation index of active distribution network components based on improved repetitive power flow is proposed;on the other hand,the structure weakness evaluation index of active distribution network components is improved.The weak link identification method based on least-squares support vector machine is proposed for distribution networks containing large-scale distributed PV.Finally,the effectiveness of the proposed method is verified by the actual data of regional distribution networks and simulation example.