摘要
2012年9月12日楚穗特高压直流发生了因穗东站交流系统接地故障导致的直流差动保护(87DCM)动作跳闸事件,暴露出原87DCM保护不仅定值偏小、延时较短,而且逻辑算法中有积分特性,不能满足区外故障时正确不动作的要求。为了提高保护的可靠性,设计了无积分特性且具有告警段、速动段、灵敏段的三段式87DCM保护,并提出了各段定值的整定原则。利用RTDS对改进后的87DCM保护进行了校核,结果表明该保护满足选择性、可靠性、灵敏性、速动性要求。目前该保护已在高肇、兴安、楚穗、牛从、普侨直流工程中全面实施应用。
On September 12,2012,the DC Differential Protection（ 87DCM） of Chuxiong-Suidong UHVDC project acted due to AC system ground fault at Suidong station,leading to a DC tripping event,which exposes that the old 87 DCMwith small setting,short delay,integral feature in logic algorithm can not meet the requirement of not tripping at external fault. In order to improve the reliability of 87 DCM,a new three-stage 87 DCMis designed which has no integral feature in logic algorithm,and the setting principles of each stage are proposed. RTDS simulation platform is employed to check the three-stage 87 DCM. It is show n that the new three-stage87 DCMmeets the selectivity,reliability,sensitivity,promptness requirements. At present the three-stage protection has been fully used in Gaopo-Zhaoqing,Xingren-Bao＇an,Chuxiong-Suidong,Niuzai-Conghua,Pu＇er-Qiaoxiang HVDC transmission projects.
出处
《南方电网技术》
北大核心
2015年第6期28-33,共6页
Southern Power System Technology
