分布式光伏电源对配电网电压波动的影响研究

分布式光伏电源接入配电网后导致电压波动加剧等问题,限制了光伏发电的快速发展。文章从理论角度分析得到光伏功率波动水平以及光伏电源接入点短路容量大小是影响配电网电压波动大小的主要因素;考虑到未来光伏容量不断增加,光伏功率波动水平必将不断提高,因此增大接入点短路容量是降低电压波动实现大量分布式光伏电源接入配电网最为可行的方法,而配电网采用环网结构能增大接入点短路容量;最后在PSCAD/EMTDC中搭建了完整的光伏电源系统以及IEEE13节点模型,仿真验证了配电网采用环网结构增大短路容量能有效削弱光伏电源对配电网电压波动的影响,为分布式光伏的良好发展奠定基础。

Research on Influences of Distributed Photovoltaic Generation on Voltage Fluctuations in Distribution Network

In recent years, distributed photovoltaic (PV) generations has been widely applied. However, when connected to distribution network, PV generation will Cause voltage fluctuations and other problems with the intermittence and randomness of its output power. In order to get a better development of PV generation ,the influences of connecting PV generation to distribution network on voltage fluctuation are analyzed theoretically. And get the conclusion that the fluctuation of output power of PV generation and network short circuit capacity will affect the voltage fluctuation. Considering the increase of PV capacity in the future, the better way to weaken voltage fluctuation is to gain the network short circuit capacity through the loop-close operation of annular network, which is also beneficial for more PV generation to be connected to distribution network and will be a must in the future. The correctness of above-mentioned analysis, which lay the foundation for the great development of distributed PV, is verified by using PSCAD/EMTDC to establish numerical examples of distribution networks with PV generation.