摘要
针对变压器传统后备保护整定配合困难、动作延迟长、灵敏性难以保证等困难,提出了变压器就地后备保护配置及整定新方法。新方法为变压器各侧配置具有正、反方向动作特性的距离保护,阻抗定值均按照实现各自功能的灵敏性要求整定,选择性则通过固定的时间定值配合实现,从而降低了变压器就地后备保护整定的复杂性。针对上述配置与整定方法可能存在速动性不足的问题,进一步构建站域后备保护系统,综合利用本站范围内的开关量信息,完成故障元件判断及断路器跳闸决策,加速站内故障切除。典型故障下的保护动作情况分析表明,站域后备保护系统能有效地与变压器就地后备保护相配合,做到快速、有选择性地切除故障元件,并具有良好的容错能力。
To solve problems existing in conventional transformer backup protection, such as increasing complexity of setting calculation, extending time delay of protection operation, and aggravating deficiency on sensitivity, a novel transformer local backup protection scheme and corresponding setting calculation method were proposed. Dual setting distance relays with forward and reverse direction operation characteristics were employed in each circuit breaker of protected transformer. Impedance setting of distance relays ensured sensitivity requirement, and selectivity requirement was satisfied through time setting coordination. So complexity of setting calculation for transformer local backup protection was reduced. However, operating speed of the new simplified local backup protection scheme still needs further improvement under some circumstances. Therefore, a substation area backup relaying scheme was designed. Digital startup information of distance relays in local substation was utilized to judge faulted elements and accelerate circuit breaker tripping. Case study results show that substation area backup relaying scheme combined with transformer local backup protection realizes fault tolerance ability and unification of selectivity, sensitivity and quickness.
出处
《电网技术》
EI
CSCD
北大核心
2017年第1期291-297,共7页
Power System Technology
基金
国网北京经济技术研究院项目(JYY-自控中心-2015-D1002)的资助
关键词
变压器后备保护
距离保护
站域后备保护
整定计算
开关量
transformer backup protection
distance relays
substation area backup relaying scheme
setting calculation
digital startup information
