Adaptive faulted phase selection for lines connecting converter-based sources

Abstract

Renewable sources with numerous converter-control operations introduce dynamic fault signatures in the network. Such nonhomogeneous situations result in maloperation of available phase selection methods at times, which may further lead to incorrect protection decisions and affect system resilience. In this paper, an adaptive phase selection method is proposed for lines connecting converter-based sources. Phase selection zones are formed based on the relations between faulted path sequence currents, which are unique to each fault type and remain independent of system conditions. The method uses local voltage and current data to compute an adaptive phase shift for selection zones and calculate an index based on signal availability for deriving decisions. Performance of the proposed method is evaluated on a renewable integrated 9-bus system using PSCAD/EMTDC simulation and found to be accurate and independent of converter-control operations, source types, and system conditions.