To analyze the impact of feeder imbalance on the transient characteristics of single-phase high-impedance grounded faults,this paper establishes an equivalent circuit for single-phase grounded faults that includes multiple feeder imbalance voltage sources.The magnitude and phase of the unbalanced voltage source of a single feeder are only related to the inherent ground imbal-ance of that feeder,while the significance of the transient fault current characteristics is related to the size of the transition resistance.A state-space-based fault transition resistance identification method is proposed,and linear regression is used to identify the single-phase ground fault resistance.From the moment the fault occurs,it will gradually decrease from a larger value.The initial resistance that affects the significant degree of fault transient characteristics is often large,which may cause no significant difference between the amplitude of the feeder transient current and the inherent current after the fault.The inherent imbalance of the feeder will seriously af-fect the accuracy of using transient characteristics for line selection.
关键词
单相高阻接地故障/馈线不平衡/故障特征/等值电路/状态空间
Key words
single-phase high-resistance ground fault/feeder imbalance/fault characteristics/equivalent circuit/state space
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