633 / 2019-04-10 20:14:22

Analysis and Countermeasure of AC Circuit Abnormality of localization Line Protection

localization,line protection,AC circuit,zero sequence current circuit failure,voltage neutral line failure

The secondary AC circuit cable for localization line protection is greatly shortened compared with the conventional wiring of the protection room. The probability of occurrence of anomalies will be reduced, but there may still occur, which will have an impact on protection. The localization protection does not acquire the external zero sequence current and the external zero sequence voltage, which will affect the effect of distinguishing the AC abnormality. As with other protections, the localization protection is not effective for discriminating zero sequence current circuit failure. This paper analyzes the abnormal conditions that may occur in the secondary protection circuit of localization protection, as well as the fault characteristics of zero sequence current failure, and proposes some countermeasures such as waveform recognition.