LVRT策略对光伏高渗透率电网频率影响分析  

Analysis of the Impact of LVRT Strategy on Frequency inGrids with High Photovoltaic Penetration Rates

作　　者：秦筱迪 杨青斌 徐亮辉 QIN Xiao-di;YANG Qing-bin;XU Liang-hui(China Electric Power Research Institute,Nanjing 210003,China)

机构地区：[1]中国电力科学研究院有限公司,江苏南京210003

出　　处：《电工电气》2024年第11期24-29,41,共7页Electrotechnics Electric

基　　金：国家电网有限公司总部科技项目(4000-202355091A-1-1-ZN)。

摘　　要：光伏逆变器的低电压穿越(LVRT)能力对支持电网安全稳定运行有极为重要的意义,在光伏高渗透率电网中,低电压穿越期间易造成电网较大的有功功率缺额,导致频率下降。分析了目前相关国标主导的LVRT策略控制下光伏逆变器的输出特性,及其低电压穿越过程中对光伏高渗透率电网频率稳定的影响;以IEEE 3机9节点网架为基础,接入光伏电站模型进行了仿真分析,对比了两种典型控制策略下低电压穿越过程中频率的变化,建议加强低电压穿越期间光伏电站对电网的有功功率支撑作用,同时保障一定量值的无功电流和有功电流输出,实现对电网的有功功率和无功功率支撑,改善光伏电站低电压穿越性能对电网的支持作用。The low voltage ride through(LVRT)capability of photovoltaic(PV)inverters plays an extremely important role in supporting the safe and stable operation of the power grid.In grids with high photovoltaic penetration rates,the LVRT period can easily lead to a significant active power deficit in the grid,causing a frequency drop.This paper analyzes the output characteristics of PV inverters under the LVRT strategies dominated by current national standards and their impact on the frequency stability of grids with high photovoltaic penetration during the LVRT process.Based on the IEEE standard 3-machine 9-node network,a PV power station model was connected for simulation analysis.The frequency changes during the LVRT process under two typical control strategies were compared.It is recommended to enhance the active power support of PV power stations to the grid during the LVRT period,while ensuring a certain amount of reactive current and active current output,to achieve active power and reactive power support for the grid and improve the support effect of PV power station LVRT performance on the grid.

关 键 词：光伏 低电压穿越 控制策略 有功功率支撑 无功功率支撑 

分 类 号：TM615[电气工程—电力系统及自动化] TM712