摘要
随着逆变型分布式电源(IIDG)高比例、灵活接入,传统的保护原理逐渐难以满足配电网的安全运行要求。与此同时,基于电力电子设备的主动探测思想提供了新思路。为此,充分利用电压源换流器的可控性,提出了适用于IIDG的谐波信号主动注入方法及其控制参数选取原则。然后,分析含T接IIDG配电网在区内外故障后所呈现的谐波电流故障特征,并揭示T接负荷分支对上述特征的影响规律,进而提出了一种基于谐波信号主动注入的含高比例IIDG配电网电流差动保护方案。最后,通过PSCAD/EMTDC仿真验证了所提方法的动作性能。测试结果表明,当存在T接分支时,所提方法仍能有效识别区内外故障,且无需额外的信号注入设备,经济性较好。
With the high penetration and flexible access of inverter-interfaced distributed generators(IIDGs),it is gradually becoming difficult for traditional protection schemes to meet the requirement for safe operation of distribution networks(DNs).At the same time,the idea of active detection based on power electronic equipment provides a new approach.To this end,based on the controllability of voltage source converter(VSC),a method for active harmonic signal injection and a selection principle for the corresponding control parameters are proposed.Then,the fault characteristics of harmonic current of DNs with T-connected IIDGs under internal and external faults are analyzed,and the influence of T-connected load branches on the above characteristics is revealed.On this basis,a current differential protection scheme based on active injection of harmonic signal is proposed for DNs with high penetration of IIDGs.Finally,the performance of the proposed scheme is verified via PSCAD/EMTDC simulation software.The test results show that the proposed scheme can effectively identify internal and external faults when there are T-connected branches,and it does not need to install signal injection equipment,which achieves good economy.
作者
李海锋
张正刚
梁远升
梁华敏
王钢
LI Haifeng;ZHANG Zhenggang;LIANG Yuansheng;LIANG Huamin;WANG Gang(School of Electric Power Engineering,South China University of Technology,Guangzhou 510641,China;Shenzhen Power Supply Bureau Co.,Ltd.,Shenzhen 440304,China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2023年第22期120-128,共9页
Automation of Electric Power Systems
基金
广东省基础与应用基础研究基金资助项目(2022A1515010906)。
关键词
配电网
分布式电源
谐波信号
主动注入
电流差动保护
T接分支
distribution network
distributed generator
harmonic signal
active injection
current differential protection
T-connected branch
作者简介
李海锋(1976-),男,博士,教授,博士生导师,主要研究方向:电力系统故障分析与继电保护。E-mail:lihf@scut.edu.cn;张正刚(1998-),男,硕士研究生,主要研究方向:含分布式电源配电网的故障分析与保护。E-mail:940580165@qq.com;通信作者:梁远升(1980-),男,博士,副教授,主要研究方向:电力系统故障分析与继电保护。E-mail:ysliang@scut.edu.cn。
