分布式光伏电源极端可接入容量极限研究

为了防止大量分布式光伏电源接入配电网后可能引起电压偏差和电压波动越限,建立了负荷和分布式光伏电源引起的电压偏差和电压波动的计算模型。并在此基础上定义了分布式光伏电源极端可接入容量极限的概念,即负荷为0的极端情况下不致引起电压偏差和电压波动问题的分布式光伏电源接入容量极限。推导了6种典型分布情况下线路电压偏差和电压波动不越限时所能允许接入的极端容量极限。针对10 k V典型线路,给出了不同线型下城市配电网和农村配电网中分布式光伏电源安全接入的极端容量极限值。结果表明,分布式光伏电源极端可接入容量极限是保守的限值,只要满足该容量极限,无论分布式光伏电源和负荷的如何分布情况,都不至于对配电网产生不可接受的电压偏差或电压波动。

Extreme capacity limitations of photovoltaic generators in distribution grids

In order to prevent voltage deviation and voltage fluctuation beyond its upper limit caused by the installation of large amount of distributed photovoltaic (PV) generators in distribution grids, the calculation models of PV generators are established to analyze the voltage deviation and voltage fluctuation. An index of the extreme capacity limitation of distributed PV generators interconnected into the idle feeder without causing the problem of voltage deviation and voltage fluctuation is defined. The extreme capacity limitations are deduced for six PV distribution patterns. The typical urban and rural distribution grids are used as examples to demonstrate the extreme capacity limitations in various cases. The results show that proposed index is rather conservative and neither problems of voltage deviation or voltage fluctuation could be avoided once the index was met.