光伏发电项目系统接入技术探讨

Discussion on System Access Technology for Photovoltaic Power Generation Projects

近年来新能源发电技术及并网规模迅速发展,光伏发电并网容量逐年增大,在电力系统中发挥着重要的作用。配电网络消纳了数量较多的光伏发电电源,这些新型发电系统的并网提高了新能源利用率,为配电网输送了电能,但也带来了电压波动、谐波、闪变等不稳定因素,甚至会造成电压越限等严重影响配电网电能质量的问题。对并网光伏发电系统应满足的技术要求进行分析,包括电能质量、谐波、电压偏差、电压波动、电压不平衡度、直流分量等;在电网电压偏差和频率异常的情况下,研究了并网光伏发电系统的响应特性应满足的故障穿越运行要求。针对并网光伏发电的运行指标,对光伏发电项目进行相应设计,包括谐波允许值、无功计算、消弧线圈等,并对其运行分析提出了相应技术要求,确保了受端配电网络安全可靠稳定运行。

In recent years,new energy generation technology and grid connection scale have developed rapidly,and the grid connection capacity of photovoltaic power generation has been increasing year by year,playing an important role in the power system.The power distribution network consumes a large number of photovoltaic power sources.The grid connection of these new power generation systems improves the utilization rate of new energy and transmits electric energy to the distribution network,but it also brings unstable factors such as voltage fluctuations,harmonics,and flicker,and even causes problems that seriously affect the power quality of the distribution network,such as voltage overruns.The technical requirements that should be met by the grid-connected photovoltaic power generation system are analyzed,including power quality,harmonics,voltage deviation,voltage fluctuation,voltage imbalance,DC component,etc.In the case of grid voltage deviation and frequency abnormality,the response characteristics of grid-connected photovoltaic power generation system should meet the requirements of fault ride-through operation.According to the operation indicators of grid-connected photovoltaic power generation,the corresponding design of photovoltaic power generation projects is carried out,including harmonic allowable value,reactive power calculation,arc suppression coil,etc.At the same time,corresponding technical requirements are put forward for its operation analysis to ensure the safe,reliable and stable operation of the power distribution network at the receiving end.