两端带并联电抗器输电线路永久故障判别

提出一种适用于两端带并联电抗器的超高压输电线路的单相自动重合闸永久故障识别方法.输电线路发生单相故障两端跳闸后,利用电流差动保护原理对断开相两端的电流量进行比较,将瞬时故障视为区外故障,永久性故障视为区内故障,根据判据判断故障为永久性或者瞬时性,以决定是否重合闸.ATP仿真结果表明该方法能准确区分永久性和瞬时性故障,判断可靠、耐过渡电阻能力强.

Identification of Permanent Faults Based on Differential Current Protection for Transmission Lines with Two Shunt Reactors

For transmission lines with two shunt reactors,this paper presents a novel method of identifying permanent faults for single-phase auto-reclosure.After the breakers of two terminals cut off the fault phase under the single-phase fault,the fault phase currents in the two terminals are compared based on the principle of differential current protection to judge whether the fault is permanent or temporary so as to determine whether to reclose the breakers of two terminals or not.Temporary faults can be regarded as external faults while permanent faults can be regarded as internal ones.ATP simulation results show that the method presented can identify permanent faults correctly and is hardly affected by grounding resistance.