Abstract:The grounding lead wires are the connection channel between the various electrical equipment or lightning protection devices and the horizontal grounding grid in substation. Once the lead wires are corroded, thinned or broken, it will pose a safety hazard. The main factors that affect the conductor impedance of the lead wires are analyzed in this paper. The change rule of the mutual impedance between two touchable nodes of the lead wires at different frequencies is researched. A corresponding measurement system is designed and developed. The criterion of the mutual impedance threshold of detecting the grounding lead wire conductor states is determined based on the theoretical calculation and experimental testing results of mutual impedance between two grounding lead wires. The strategy of screening and testing the lead wires conductor defects are proposed. The testing results show that this method can effectively diagnose the defect state of the grounding lead wires. The detecting reliability are improved. The method can be used for the maintenance of grounding grid in practical engineering.
刘洋, 付晓东. 变电站接地引下线缺陷筛查方法与技术[J]. 电气技术, 2022, 23(1): 95-101.
LIU Yang, FU Xiaodong. Screening method and technology of grounding lead wires defects in substation. Electrical Engineering, 2022, 23(1): 95-101.