Patent ID: 7973536
Filing Date: 2011-07-05
Classification: G01R,H02H

Abstract:
1. A method of protecting a power apparatus from a fault in an AC electrical power network that operates at a fundamental power frequency, the method comprising: receiving a first signal from a first Rogowski coil positioned to filter a first traveling wave current on a first transmission line of the AC electrical power network from a current component corresponding to the fundamental power frequency, wherein the first signal is indicative of a polarity of the first traveling wave; receiving a second signal from a second Rogowski coil positioned to filter a second traveling wave current on a second transmission line of the network from a current component corresponding to the fundamental power frequency, wherein the second signal is indicative of a polarity of the second traveling wave; determining, based on the first signal and the second signal, the location of the fault in the network; halting a current flow on a transmission line of the network based on the determination of the fault location; generating a first tracking pulse having a predetermined amplitude and width in response to a first detected traveling wave current that exceeds a first predetermined threshold value; and generating a second tracking pulse having a predetermined amplitude and width in response to a second detected traveling wave current that exceeds a second predetermined threshold value.