Transmission Line Fault Detection and Identification in an Interconnected Power Network

This paper proposes a novel hybrid technique to detect and identify transmission line faults in an Interconnected Network using the measurements from Phasor Measurement Units (PMUs). The proposed fault detection and identification technique is based on Positive Sequence voltage and current measurement from PMUs. The proposed algorithm for fault detection and identification is deployed in two stages: First stage is the detection of fault using Positive Sequence Voltage Magnitude (PSVM) and second stage is the fault-location identification through Positive Sequence Current Angle Differences (PSCADs). Sometimes, both of these condition might fail to detect and identify the fault, then another condition based on Positive Sequence Current Magnitude (PSCM) is employed. The proposed hybrid technique for fault detection and fault line identification is tested on a five area interconnected transmission network that employs PMUs at its buses/nodes. During fault, the sequence of PSVM near the faulty line changes or its value drops to minimum, thus detecting the fault. If the PSVM condition fails, then fault is detected by observing sequence and magnitudes of PSCM at all the buses. Fault identification is performed by comparing the PSCAD (Positive Sequence Current Angle Difference) of corresponding node with PSCADs of remaining nodes and maximum PSCAD identifies the faulty line. Simulations are carried out in MATLAB/SIMULINK and results are given for the five area power system. The results verify the proposed fault detection and identification algorithm.