华电技术 ›› 2020, Vol. 42 ›› Issue (1): 45-49.

• 研究与开发 • 上一篇    下一篇

双母单分接线方式下母线差动保护逻辑完善方案

  

  1. 许继集团有限公司,河南许昌〓461000
  • 出版日期:2020-01-25 发布日期:2020-03-20

An improvement scheme for busbar differential protection logic applied in singlesectionalized doublebusbar connection mode

  1. XJ Group Corporation, Xuchang 461000, China
  • Online:2020-01-25 Published:2020-03-20

摘要: 针对220kV母线保护装置集中入网试验预检测过程中,模拟母联支路电流互感器(CT)断线工况下误跳非故障母线的母联元件问题进行分析,指出了双母单分接线方式下现有大差和小差保护逻辑存在的局限性,提出了通过引入中差保护判据,再次划分3条母线的保护范围,以准确定位具体故障母线的措施。介绍了双母单分接线方式下,母线中差保护范围、差流计算、比率制动特征方程以及在保护逻辑中的具体应用。仿真试验表明,增加中差保护判据后达到了预期的防误动效果,在保证保护动作速动性和灵敏性的同时,提高了差动保护的可靠性。

关键词: 双母单分接线, 母联CT断线, 母线保护, 中差保护判据, 比率制动特性

Abstract: Due to the incorrect tripping of nonfault busbar with the simulated disconnected bustie circuit current transformer(CT) during the pretesting process in the centralized network test for a 220kV busbar protection device, the limitation existing in big difference and small difference protection logic for singlesectionalized doublebusbar connection mode was proposed. After introducing the medium differential protection criterion, the protection ranges of three busbars were divided again in order to locate the specific fault busbar accurately. The differential protection range, calculation of the differential current, ratiorestraint characteristic equation and their specific applications in the protection logic in singlesectionalized doublebus connection mode were described. Through a simulation test, it was verified that adding medium differential protection criterion could effectively avoid maloperation, improve the quickness and sensitivity of the protection.

Key words: singlesectionalized doublebus connection, bustie CT disconnection, busbar protection, medium differential protection criterion, ratiorestraint characteristic