作　　者： ; ; ;

机构地区： 山东大学电气工程学院

出　　处： 《电力自动化设备》 2008年第11期1-7,共7页

摘　　要： 当中性点非有效接地系统发生单相接地后,由于故障电流太小难以检测,使得接地线路的判定困难。对此,提出了一种全新而有效的选线方法,其基本思想是通过对系统中性点实行可控的有效接地,从而将中性点非有效接地系统在短时间内变成中性点有效接地系统,以产生强度足够大但又不至于影响系统正常运行的短路脉冲用于故障线路的选定。利用频谱分析建立了区分故障与非故障线路短路脉冲的有效判据,并基于该判据对所述选线方法的灵敏度进行了分析,最终通过动模实验对该方法的有效性进行了印证。 For system with non-effectively grounded neutral point,the identification of line experiencing single- phase to ground fault becomes very difficult due to too small faulty current. A new way is proposed that converts the ungrounded system into a grounded system temporarily by an effectively controllable grounding at neutral point,which produces fault current that is large enough to identify the faulty line while small enough not to cause system problems. The criterion to distinguish the short- circuit impulse of faulty line from those of healthy line is established by spectral analysis, based on which the sensitivity of proposed method is analyzed. Its effectiveness is proved by lab experiment.

关 键 词： 故障选线 中性点非有效接地系统 中性点不接地系统 谐振接地系统 消弧线圈

领　　域： [电气工程]