光伏电站接入混联电网的稳定性影响研究

Study on stability of PV power station connected to hybrid power network

随着可再生能源大量接入混联电网,电网系统的稳定性受到新能源接入的不确定性影响。本文针对随机性、间歇性和可控性差的大规模光伏电站接入混联电网使得区域电网的潮流、动态稳定性发生变化,引起的电力系统稳定性问题,研究了光伏电站光照强度变化,出力不同和紧急控制切机对混联电网的稳定性影响。文章建立了光伏发电实用模型,该模型适用于温度和光照强度变化大的环境,以甘肃电网2017年网架和运行方式为基础,深入分析了光伏电站接入电网后,当光照强度变化,光伏出力不同,故障切机容量100 MW到500 MW对混联系统稳定性的影响。研究结果表明,光照强度与光伏电站出力成正比例;光伏出力增大时,系统的稳定性增强;光伏切机比例增大,系统的稳定性减弱;进一步提出改善含光伏电站混联电网稳定性的措施,为地区光伏电站的规划和并网提供重要的参考价值。

With the large number of renewable energy accessing to the mixed power grid,the stability of the system is affected by the uncertainty of new energy access.In this paper,a large scale photovoltaic power station with random,intermittent and poor controllability can change the power flow and dynamic stability of the regional power grid,and the stability of the power system is caused by the changed of the power system.The influence of the light intensity change,the different output and the emergency control machine on the stability of the hybrid power grid is studied.In this paper,a practical model of photovoltaic power generation is established.This model is suitable for the environment with great change in temperature and light intensity.Based on the network frame and operation mode of Gansu power grid in 2017,it is deeply analyzed that when the photovoltaic power station is connected to the power grid,the light intensity changes,the PV output is different,the fault cutting capacity is 100 MW to 500 MW for the stability of the mixed system.The effect of sex.The results show that the light intensity is proportional to the output of the photovoltaic power station,the stability of the system is enhanced when the PV output increases,the proportion of the photovoltaic cutting machine is increased and the stability of the system is weakened,and the measures to improve the stability of the mixed power grid with the photovoltaic power station are further proposed,which will provide an important value plan for the planning and grid connection of the photovoltaic power stations.