摘要
在新型电力系统的发展格局下,作为载波高频通信元件的阻波器逐渐被淘汰,而仅依靠超高压母线现有边界元件能否为单端暂态量保护提供强健的边界滤波作用,暂时缺乏充分的认知。为此,该文建立精确的变电站母线高频暂态模型,发现电容式电压互感器的高频滤波特性能够显著增强线路边界的滤波性能下限,其使得保护方案的最小保护范围也得以超过线路半长;其次,基于区内外故障时电流行波高低频频带能量差异构造全新暂态量保护判据,以有效适应母线不同进出线数目的情况;继而,通过主动收缩保护范围以躲避对侧母线附近的保护盲区,形成可靠的单端暂态量欠范围式保护方案;最后,基于PSCAD仿真平台验证所提保护方案的有效性、灵敏性与可靠性。
With the flourishing development of the new power system,the line trap,as the element of the power line carrier,is gradually phased out.And there is a lack of sufficient research on whether the existing boundary elements of extra-high voltage(EHV)transmission can serve as the robust line boundary to filter high-frequency signals for non-unit transient-based protection.Therefore,in this paper,an accurate high-frequency transient model of substation bus was established,and the analysis shows that the high-frequency filtering characteristics of capacitive voltage transformer can significantly enhance the lower limit of filtering performance of line boundary,which makes the minimum protection range of the protection scheme exceed the half-length of the line.Furthermore,based on the difference in the high-frequency and low-frequency energy spectrum of the inside-zone and outside-zone fault current traveling wave,the new transient protection criterion was constructed to effectively adapt to the situation of the different numbers of incoming and outgoing bus lines.Then,by actively shrinking the protection range to avoid the blind zone near the opposite bus,a reliable non-unit transient-based underreach protection was formed.Finally,the proposed protection scheme was performed based on the PSCAD platform to verify its effectiveness,sensitivity,and reliability.
作者
吴宇奇
黎钊
肖澍昱
黄梓欣
李正天
魏繁荣
林湘宁
WU Yuqi;LI Zhao;XIAO Shuyu;HUANG Zixin;LI Zhengtian;WEI Fanrong;LIN Xiangning(State Key Laboratory of Advanced Electromagnetic Engineering and Technology(Huazhong University of Science and Technology),Wuhan 430074,Hubei Province,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2022年第S01期70-81,共12页
Proceedings of the CSEE
基金
国家重点研发计划项目(2021YFB2401000)
国家电网有限公司科技项目(SGSDDK00WJJS2200105)
关键词
超高压输电
单端暂态量保护
线路边界
电容式电压互感器
频带能量
extra-high voltage transmission
non-unit transient-based protection
line boundary
capacitive voltage transformer
energy spectrum
作者简介
吴宇奇(1997),男,博士研究生,研究方向为新型电力系统保护与控制,798893267@qq.com;通信作者:肖澍昱(1997),女,硕士研究生,研究方向为新型电力系统下继电保护,1173046492@qq.com。
