计及不确定性的分布式光伏接入配电网极限容量评估

针对分布式光伏大量并网导致的配电网电压越限风险增加的问题,分析了不同天气类型下光伏出力特性,提出了基于光伏出力波动特性的广义天气类型聚类划分方法和基于净空理论的光伏出力时间序列模型构建方法。所构建的模型能反映实际光伏出力的时序性和波动性,建立了基于各时段节点电压越限概率与严重度函数的系统电压越限风险评估指标,据此提出采用混合逼近法求解配电网中分布式光伏的极限接入容量。最后,以典型IEEE33节点配电系统和南方电网某地区实际线路为例,分析了不同负荷特性、负荷水平和线路类型下的系统电压越限风险,从这三方面分别对分布式光伏接入配电网的极限容量进行评估。

Evaluation of ultimate capacity for distributed photovoltaic access distribution network considering uncertainty

Aiming at the problem of the increasing voltage over limit risk by a large number of distributed PV access network, this paper analyses the PV output characteristics under different weather types, presents a generalized weather type clustering method based on photovoltaic output fluctuation characteristics, and builds a method of PV output time series based on clearance theory. The model can reflect time series characteristics and volatility of actual PV output, the risk assessment index of system voltage exceeding the limits based on the probability and severity of node voltage at each time interval is established. On this basis, using hybrid approximation to solve the ultimate capacity of distributed PV access network is proposed. Finally, a typical IEEE 33-node power distribution system and an actual line of a region of China Southern Power Grid are taken as examples to analyze the risk of system voltage under different load characteristics, load levels and line types. From these three aspects, the limit capacity of distributed PV access network is evaluated. This work is supported by National Natural Science Foundation of China (No. 51377060).