A moving sum approach for fault detection of power systems

This paper proposes a fault detector for digital relaying based on a moving sum index. The sum of the current samples over one cycle window has been used as the qualifier to detect the occurrence of faults in a power system. Simplicity and accuracy are the two attractive features of the method. The method is tested under a variety of fault and disturbance conditions in a typical power system. A comparative assessment with existing techniques is carried out to establish the effectiveness of the method. The approach can also be applied for fault classification of a distance relay.