CAJ | 학술논문

某地区电网110kV系统发生单相接地故障时,引起升压站110kV出线零序Ⅰ段保护越级误动作。通过故障录波图和现场勘查,发现升压站不接地变压器中性点保护间隙击穿放电是事故起因,变电站保护装置定值配合及主变压器中性点保护间隙布置方面也存在问题。对此,提出了有针对性的防误动改进措施,现场应用效果良好。
모지구전망110kV계통발생단상접지고장시,인기승압참110kV출선령서Ⅰ단보호월급오동작。통과고장록파도화현장감사,발현승압참불접지변압기중성점보호간극격천방전시사고기인,변전참보호장치정치배합급주변압기중성점보호간극포치방면야존재문제。대차,제출료유침대성적방오동개진조시,현장응용효과량호。
A mal-operation of line No. I zero-sequence protection of I10 kV wind farm booster station is resulted from a out- area single-phase ground fault occurring on 110 kV regional power grid grounding system. The unearthed transformer neutral point protection gap strike and discharged in booster station is the fault cause, which is found by the recorded fault waveforms and scene investigation. In addition, it also points out the existing problems due to relay settings improper coordination in substation and problem of neutral point protection gap arrangement Ior main transformer. Through detailed theoretical analysis on the mal-operation according to the area power system situation, an improving measure to avoid protection malfunction is put forward. The application results on site of substation are verified effective.