摘要
规模化光伏发电是可再生能源利用的重要形式之一。由并联运行的光伏发电单元及长距离汇集线路组成的规模化光伏发电系统,其暂态功率特性将会显著影响电网受扰行为和光伏并网安全。该文建立光伏发电单元暂态仿真模型,并在PS D-BP A电力系统分析软件中开发完善了仿真功能。在此基础上,指出交流电压受扰跌落时,光伏发电单元具有低电压大电流的运行特征,揭示了长距离汇集线路呈现出暂态无功负荷特性的机理,并评估了影响因素。基于此,提出改善汇集线暂态无功特性的技术措施。针对大容量光伏接入的青海海西电网,验证了差异化整定低压保护参数或主动拉停少量汇集线路2种控制措施对降低大规模光伏低电压无序脱网威胁的有效性。
Large-scale photovoltaic （PV） power generation is one of the important forms of solar energy resources applications. The transient power characteristic of scaled photovoltaic grid-connected systems, which consisted of many paralleled generation units and long-distance transmission line, will affect the disturbed behavior of power grid and the security of PV operating. In this paper, the electromechanical transient model was established and the simulation function was developed for PV generation system firstly. On this basis, it was pointed out that the PV generation unit had constant active power operation characteristic with high outputt current during low AC voltage. The mechanism that long-distance grid-connected line has transient reactive load characteristics with AC voltage dropping was revealed. The influence factors on transient reactive characteristic were evaluated and the improvement measures were proposed. The Qinghai-Haixi power grid with large-capacity photovoltaic incorporated was selected as case study. The simulation results verify that the threat of large-scale PV disorderly off-grid can be degraded by differentiated parameters setting of low-voltage protection or tripping the connection lines initiatively.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2015年第5期1059-1071,共13页
Proceedings of the CSEE
基金
国家863高技术基金项目(2011AA05A105)~~
关键词
光伏发电
低压保护
暂态功率特性
并网系统
汇集线路
拉停线路
无序脱网
photovoltaic （PV） generation
low-voltage protection
transient power characteristics
grid-connected system
power congesting line
tripping line
disorderly off-grid
