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Accurate fault location in distribution systems greatly shortens maintenance time and improves reliability. This paper presents novel methods to pinpoint fault location and identify possible bad measurements for enhanced accuracy. It is assumed that network parameters and topology of the distribution network are available. The methods are applicable to a single fault as well as simultaneous faults and are applicable to both balanced and unbalanced networks. The methods utilize synchronized voltage and current phasor measurements to locate the fault. The methods are validated by simulation studies using the modified IEEE 34-Node Test System. Case studies have demonstrated that the methods are suitable for distribution systems with high penetration of distributed generations. [ABSTRACT FROM AUTHOR]

This paper presents a new method for locating faults on radial distribution systems utilizing local voltage and current measurements. The method considers feeder shunt capacitances, is applicable to any type of faults, is suitable for unbalanced networks and does not require fault type information. The method is also independent of source impedance. Analytical analysis is utilized to obtain a generic performance equation for any type of faults, which reduces or eliminates iterative steps to reach the fault location. A process to trim down multiple estimates due to laterals is discussed. Evaluation studies based on simulated data have demonstrated the effectiveness of the proposed solution. [ABSTRACT FROM AUTHOR]

This paper presents a novel fault location method for transmission lines. The proposed method extends an existing method to locate faults by employing voltage and current measurements at one bus, which can be the bus of the faulted line or be far away from the faulted line. The method is applicable if a loop exists that encloses the faulted line, and the bus, of which the voltage is used, and the branch, of which the current is used. The during-fault positive-sequence bus impedance matrix is derived. Then superimposed voltages and currents due to the fault are expressed as a function of fault location and related transfer and driving point impedances. Consequently, the fault location can be evaluated using the obtained measurements. The distributed parameter line model is adopted to consider the shunt capacitances of the line. The proposed method is independent of fault resistance and fault type. Simulation studies have been carried out based on a 27-bus power system, and promising results have been achieved. [ABSTRACT FROM AUTHOR]

This article presents a novel fault location algorithm for parallel transmission lines for scenarios where only limited synchronized voltage and current measurements are available. Existing methods usually request measurements at the faulted line to be available. However, this may not always be the case due to the limited number of recording devices placed in a power system. The proposed method makes the most of available measurements and does not require the measurements to be captured from the faulted line. The pre-fault and during-fault bus impedance matrices for the positive-sequence network are derived. Synchronized bus voltages and branch currents are then expressed as a function of fault location and line parameters. As a result, fault location can be estimated using the obtained measurements. The distributed parameter line model is adopted to fully consider the shunt capacitances of the line. To eliminate the influence of bad measurements, optimal estimation theory is adopted for enhanced accuracy of the fault location estimate. Simulation studies have been carried out based on a 27-bus power system, and encouraging results have been achieved. [ABSTRACT FROM AUTHOR]

In electric power systems, not all fault conditions remain unchanged during faults. An evolving fault has one characteristic initially and changes to a different condition subsequently. Locating evolving faults is challenging due to the change in fault type shortly after the fault initiation. This paper presents a new approach for estimating the locations of evolving faults on transmission lines. By using sparse wide area voltage measurements, this method is able to accurately locate evolving faults without requiring measurements from either end of the faulted line. There is no need to detect whether a fault is an evolving fault or not. Fault type information is not a necessity either, and the change of fault phases does not affect the estimation accuracy. In addition, the algorithm is applicable to both single-circuit and double-circuit lines, and the transmission lines can be either transposed or untransposed. Distributed parameter line model is adopted to fully consider the shunt capacitances of the transmission lines. Electromagnetic Transient Program (EMTP) is employed to simulate transmission system, and quite accurate results have been achieved. [ABSTRACT FROM AUTHOR]