A Harmonic-Based Method of Fault Detection During Power Swing

Distance relay detect fault and distance of fault in the transmission line. But during power swing malfunction occurs and it trips circuit breaker (CB) for which power swing increase again and causes another circuit breaker trip. This recurring process may cause power blackout if it is not stopped immediately. Power swing blocking (PSB) relay is used to block distance relay during power swing. But if any fault occurs during power swing, it needs to unblock the distance relay and trip the CB for clearing the fault. Our proposed method overcomes the shortcoming of the conventional method of unblocking distance relay during power swing when a fault occurs. On this paper a new method has been proposed to detect a fault during power swing using total harmonic distortion of voltage. To demonstrate the effectiveness of the proposed method here we conduct a simulation of a single machine infinite bus system in PSCAD/EMTDC. Various simulation studies has been studies have been performed on a SMIB system developed PSCAD/EMTDC.