摘要
逆变型分布式电源(inverter-interfaced distributed generator,IIDG)的接入改变了馈线的潮流分布和故障特性,给传统馈线电流保护方法带来了挑战。为此,首先研究采用PQ控制策略的IIDG故障等值模型,分析含T接IIDG和负荷的馈线的故障特征,并构建基于正序电压幅值的故障特征量,该特征量能准确反映区内故障;分析不同故障位置、IIDG与负荷的接入位置对故障特征量的影响,提出一种基于正序电压故障特征量的馈线纵联保护新原理,该方法能够避免保护出现死区情况,对线路全长进行保护。为进一步提高保护性能,利用IIDG退出运行时的故障特征量构造辅助判据,以规避IIDG意外退出运行时保护误动作的风险。仿真测试结果验证了所提方法的有效性。
The access of the inverter-interfaced distributed generator(IIDG)changes the power flow distribution and fault characteristics of the feeder,bringing challenges to the traditional current protection methods.Based on the fault equivalent model of the IIDG with a PQ control strategy,this paper studies the fault characteristics of the feeder T-connected with the IIDG and load,and establishes the fault characteristic variable on the basis of positive sequence voltage which can response correctly to local fault.By analyzing the effects of different fault locations,accessing locations of IIDG and load on the fault characteristic variable,the paper proposes a new method of the feeder pilot protection based on the positive sequence fault characteristic variable which can protect the full length of the feeder without the dead zone.To improve the protection performance,the method includes an extra criterion to prevent the protection from maloperation caused by sudden quitting out of the IIDG.Simulation test verifies the effectiveness and reliability of the proposed protection method.
作者
罗竟哲
李杰
王钢
LUO Jingzhe;LI Jie;WANG Gang(School of Electric Power Engineering,South China University of Technology,Guangzhou,Guangdong 510641,China)
出处
《广东电力》
2022年第8期41-49,共9页
Guangdong Electric Power
基金
国家自然科学基金项目(51477057)。
