배전자동화 중앙장치에서 필터링 알고리즘을 통한 고장표시 오류 개선방법

In this paper, an filtering method of FI(Fault Indication) information generated by FRTU(Feeder Remote Terminal Unit)s is proposed for the present DAS(Distribution Automation System). In order to find fault area, correct FI information should be generated. But when a single line-to-ground fault occurs, FI information is generated in downside of the fault in some circumstance because existing FI algorithm considers only magnitude. These wrong FI information can be removed by changing existing algorithm. An improved algorithm considers both the direction of zero-sequence current and the phase of three-phase current&voltage. But many FRTUs are distributed in DAS and Changing the algorithm all of FRTU will spend a lot of time and cost. On the other hand, an filtering algorithm proposed in this paper can substitute for it. The filtering algorithm also considers both the direction of zero-sequence current and the phase of three-phase current&voltage. In case study, the proposed method has been shown the reasonability in filtering the fault indication information.