摘要
现有含分布式电源(DG)的配网可靠性评估研究大多针对孤岛运行特性,但实际系统中孤岛运行方式目前却少有采用,为此开展了基于DG并网运行的可靠性评估研究。在忽略DG自身停运的情况下,并网运行DG主要通过设备容量约束影响可靠性水平。由于DG出力具有随机性,随着其数量的增加,计算量将显著增大,为此提出了减小计算量的策略:将所有馈线分为放射式馈线和存在联络关系的若干个馈线集合;对于有联络馈线集合中未通过转供容量约束校验的馈线,提出了含出力恒定DG的馈线容量约束考虑方法,并引入点估计法考虑DG出力随机性;对于其他馈线,则不考虑并网运行DG对可靠性指标的影响。分析表明,并网运行DG并非总是有利于供电可靠性的提高。算例结果表明,通过馈线分类和点估计算法可大大减小计算量,且误差较小。
Existing reliability assessment research on distribution systems with distributed generators（DGs） is mostly conducted based on isolated island mode rarely used in real system. Therefore, in this paper research on reliability assessment under grid-connected operation mode of DGs is performed. Grid-connected DGs influence reliability indexes mainly by changing transfer capacity with their own outage rates ignored. Because of DG power output randomness, execution time will increase significantly with DG number increase. For this reason, several strategies of reducing execution time are proposed. Firstly, all feeders are divided into radial ones and those with ties. Secondly, for those feeders with ties not satisfying transfer capacity constraint, a method considering feeder capacity constraints is presented with constant DG power outputs, and point estimation method is used to solve randomness problem of DG power outputs; for the other feeders, influence of grid-connected DGs on reliability is ignored. Analyses show that grid-connected DG does not improve power supply reliability for sure. Numerical examples show that feeder classification and point estimation method can reduce execution time significantly with minor error.
作者
韦婷婷
王主丁
寿挺
万凌云
赵丹阳
WEI Tingting WANG Zhuding SHOU Ting WAN Lingyun ZHAO Danyang(State Key Laboratory of Power Transmission Equipment ＆ System Security and New Technology （Chongqing University）, Shapingba District, Chongqing 400044, China State Grid Hangzhou Xiaoshan Power Supply Company, Hangzhou 311201, Zhejiang Province, China Electric Power Research Institute of State Grid Chongqing Electric Power Company, Yubei District, Chongqing 401123, China)
出处
《电网技术》
EI
CSCD
北大核心
2016年第10期3006-3012,共7页
Power System Technology
关键词
中压配电网
可靠性评估
分布式电源
并网运行
点估计法
medium voltage distribution system
reliability assessment
distributed generator
grid connected operation
point estimation method
