Patent ID: 8941387
Filing Date: 2015-01-27
Classification: G01R,Y04S

Abstract:
1. A method for determining the distance to electrical faults in electrical power networks, the method being accomplished in the time domain, the method comprising: receiving a plurality of three-phase, sinusoidal electrical waveforms over a plurality of electrical power lines in an electrical power network; determining a plurality of nominal electrical parameters for the electrical power network having a source voltage, the plurality of nominal electrical parameters associated with a state of the electrical power network in the absence of at least one transitory sub-cycle electrical fault in the network; subsequently sampling a plurality of faulted electrical parameters of the electrical waveforms when the at least one transitory sub-cycle electrical fault exists along or between any of the plurality of electric power lines in the network; determining a plurality of net fault electrical parameters for the electrical power network, each of the net fault electrical parameters being a difference between one of the plurality of nominal electrical parameters and an associated one of the faulted electrical parameters; determining a plurality of inductances based at least in part upon the net fault electrical parameters and the faulted electrical parameters, and based at least in part upon voltage injection approaches that obtain an equivalent circuit of the electrical power network, wherein the equivalent circuit is obtained in part by injecting a nominal voltage at a theoretically faulted location and by ignoring the source voltage, the plurality of inductances being representative of inductances present in the network when the at least one transitory sub-cycle electrical fault exists in the network; analyzing the plurality of inductances to determine a distance to the at least one electrical fault, the distance being determined regardless of when in time the fault occurs, the sub-cycle being located anywhere on any of the plurality of sinusoidal electrical waveforms.