摘要
由于逆变型分布式电源(inverter interfaced distributed generation,IIDG)输出具有非线性特征,配电网常规的故障分析方法难以揭示故障后工频变化量的特性,而网络参数的不平衡更增加了分析难度。为此,首先建立IIDG的故障工频变化量等值模型,并分析其特性规律;然后,针对不平衡网络,通过并联补偿电流源的方式建立不平衡元件的序分量等值模型,进而提出一种计及脱网时序、基于序网络迭代修正的含IIDG不平衡配电网故障工频变化量计算方法;最后,基于PSCAD/EMTDC对所提算法进行仿真验证。仿真结果表明所提算法可准确、快速地求解含IIDG不平衡配电网故障后的工频变化量(幅值最大相对误差小于1%),可用于基于工频变化量故障特征的继电保护原理研究与性能分析。
Because the output of the inverter interfaced distributed generation(IIDG)has nonlinear characteristic,the conventional fault analysis methods of the distribution network are difficult to reveal the characteristics of power frequency variations after the faults,and the imbalance of network parameters increases the analysis difficulty.Therefore,an equivalent model of IIDG s fault power frequency variation is established firstly,and its characteristic law is analyzed.Secondly,aiming at the unbalanced network,the sequence component equivalent model of unbalanced elements is established by parallel compensating current sources,and then a calculation method of fault power frequency variation of the unbalanced distribution network with IIDG based on iterative correction of sequence network considering the off network sequence is proposed.Finally,the proposed method is verified by simulation based on PSCAD/EMTDC.The results show that the proposed method can accurately and quickly solve the power frequency variation of the unbalanced distribution network with IIDGs and the maximum relative error of amplitude is less than 1%,which proves it can be used for the research of relay protection principle and performance analysis based on the fault characteristics of power frequency variation.
作者
李海锋
张正刚
梁远升
湛雨铟
王钢
LI Haifeng;ZHANG Zhenggang;LIANG Yuansheng;ZHAN Yuyin;WANG Gang(School of Electric Power Engineering,South China University of Technology,Guangzhou,Guangdong 510641,China)
出处
《广东电力》
2023年第5期27-38,共12页
Guangdong Electric Power
基金
广东省基础与应用基础研究基金项目(2021A1515010631、2022A1515010906)。
关键词
逆变型分布式电源
不平衡配电网
工频变化量
脱网时序
故障分析方法
inverter interface distributed generation
unbalanced distribution network
power frequency variation
off network sequence
fault analysis method
