摘要
特高压交直流电网过渡期"强直弱交"矛盾突出,直流落点地区交流系统断路器失灵保护故障切除时间长,易导致直流换相失败甚至直流闭锁故障,故障期间暂态能量巨大对电网造成严重冲击。为降低交流电网扰动导致的直流换相失败风险,缩短失灵保护系统动作时间,实现故障快速隔离,通过分析影响失灵保护故障切除时间的关键因素,提出了一种基于站域的失灵保护提升方案。所提出的站域失灵保护使用本站及相邻站状态量信息和模拟量信息构建差动区,从机理上消除TA拖尾的影响,大幅度缩减故障切除时间,有效降低了直流发生连续换相失败和闭锁的风险,提高了大电网安全稳定水平。
There are prominent contradictions of ＂strong DC and weak AC＂ during the transition period of UHV AC/DC hybrid power grid.The long fault clearing time of circuit breaker failure protection of AC power system in the DC terminal location area may easily lead to the DC commutation failure even the DC blocking fault and the huge transient energy during the fault period will bring serious impact to power grid.In order to reduce the risk of DC commutation failure caused by the disturbance of AC power grid,shorten the action time of failure protection system and realize the rapid isolation of fault,an improvement scheme of failure protection based on substation area is proposed.State information and analog information from local and adjunction substations are used to construct the differential zone in the proposed substation area failure protection,which can eliminate the influence of CT trailing from the mechanism,reduce greatly the fault clearing time,effectively reduce the risks of DC continuous commutation failure and blocking fault and improve the security and stability operation level of large power grid.
作者
郄朝辉
王寅丞
孙良凯
崔晓丹
刘福锁
李兆伟
QIE Zhaohui;WANG Yancheng;SUN Liangkai;CUI Xiaodan;LIU Fusuo;LI Zhaowei(Nari Group Corporation,Jiangsu Nanjing 211106,China State Grid Electric Power Research Institute,Jiangsu Nanjing 211106,China)
出处
《广西电力》
2018年第5期1-5,24,共6页
Guangxi Electric Power
关键词
故障冲击抑制
失灵保护
站域信息
故障切除时间
fault impact suppression
failure protection
substation area information
fault clearing time
