An electric power delivery system may be protected upon occurrence of a fault condition by the systems and methods disclosed herein by detecting the fault condition and signaling a protective action before the overcurrent condition reaches the protective equipment. The protective action may be an opening of a circuit breaker or engagement of a fault current limiter. The overcurrent condition may be a non-steady-state condition. The fault may be detected using traveling wave or incremental quantity techniques.

A method detects a fault on a line of an electrical power supply system, in which current values are measured at the line ends of the line and the current values are used to check whether there is a fault on the line. In order to perform monitoring of the line such that faults can be detected comparatively quickly and sensitively, it is proposed that voltage values are also measured at the line ends. The respective measured current and voltage values are used to ascertain respective comparison current values indicating the current flowing at a comparison location on the line and the respective comparison current values are used to check for the presence of a fault on the line, and a fault signal is generated if the check has resulted in a fault present on the line being detected.

A method for identifying a faulted DC power transmission medium in a multi-terminal DC electrical network is provided. The DC electrical network includes multiple terminals connected via DC power transmission media. The method includes detecting a fault occurring in the DC power transmission media and, after detecting the fault, measuring a surge arrival time at each terminal, each surge arrival time being the difference between the time of detecting the fault and the time of arrival of an electrical wave surge generated by the fault at the corresponding terminal. The method further includes comparing the surge arrival times between the terminals to identify DC power transmission media in which the fault is not located, allocating a healthy status to the media in which the fault is not located, and identifying the faulted DC power transmission medium as being the DC power transmission medium/media without a healthy status.

An intelligent electronic device (IED) may detect arrival times and/or other characteristics of traveling waves and/or reflections thereof to determine a distance to a fault location in terms of per-unit length. An IED may convert between line distances, line-of-sight distances, straight-line distances, and/or terrain-based distances. An IED may refine one or more physical line parameters used for traveling wave-based location calculations for iterative improvements in accuracy. For instance, an IED may compare reported distances to fault locations with field-verified, confirmed fault locations to refine physical line parameters used in future location calculations. Similarly, an IED may identify which of a plurality of towers corresponds to a fault location based on a mapping of towers on a per-unit scale. Confirmed fault locations may be used to update or refine the mapping to improve future tower identification relative to per-unit fault location.

The present disclosure pertains to systems and methods to detect faults in electric power delivery systems. In one embodiment, a data acquisition system may acquire a plurality of electric power delivery system signals from an electric power transmission line. A traveling wave system may detect a traveling wave based on the plurality of electric power delivery system signals received from the data acquisition system. The traveling wave may be analyzed using a first mode to determine a first mode arrival time and using a second mode to determine a second mode arrival time. A time difference between the first mode arrival time and the second mode arrival time may be determined. A fault location system may estimate or confirm a location of the fault based on the time difference. A protection action module may implement a protective action based on the location of the fault.

The present disclosure pertains to systems and methods for monitoring traveling waves in an electric power system. In various embodiments, a data acquisition subsystem may acquire electric power system signals. A traveling wave detection subsystem may detect two or more traveling waves based on the electric power system signals and determine a location of an event triggering the traveling waves. A traveling wave security subsystem may selectively generate a restraining signal based on the location of the event as within a blocking zone. A protection action subsystem may implement a protective action when the location is outside of a blocking zone. In various embodiments, a protective action will not be implemented for traveling waves launched from known locations of switching devices operating normally. Further, protective actions may be restrained if a magnitude of a traveling wave differs from an expected value based on a pre-fault voltage.

The present disclosure pertains to systems and methods for analyzing traveling waves in an electric power delivery system. In one embodiment, a system may comprise a traveling wave identification subsystem to receive electric power system signals and identify a plurality of incident, reflected, and transmitted traveling waves. A first traveling wave may be selected from the incident and transmitted traveling waves, and a first distortion may be determined. A second traveling wave subsequent to the first traveling wave, may selected from the incident traveling waves and a second distortion may be determined. A traveling wave analysis subsystem may compare the first distortion and the second distortion and determine whether the first distortion is consistent with the second distortion. A protective action subsystem may implement a protective action based on a first determination that the first distortion is consistent with the second distortion.

An electric power delivery system may be protected upon occurrence of a fault condition by the systems and methods disclosed herein by detecting the fault condition and signaling a protective action before the overcurrent condition reaches the protective equipment. The protective action may be an opening of a circuit breaker or engagement of a fault current limiter. The overcurrent condition may be a non-steady-state condition. The fault may be detected using traveling wave or incremental quantity techniques.

A method can be used for fault location in a power transmission line connecting a first terminal with a second terminal. Arrival times of a first peak and a second peak of travelling waves are detected from measurements carried out at the first and second terminals. a rough location of a fault is identified based on a comparison of the arrival times obtained for the travelling waves detected from the measurements carried out at the first terminal, and the arrival times obtained for the travelling waves detected from the measurements carried out at the second terminal. The fault location is estimated based the rough location, the arrival times of the first and second peaks of the travelling waves detected from measurements carried out at the first and second terminals, and a length of the power transmission line.

The present disclosure relates to calculating a fault location in an electric power transmission system based on traveling waves. In one embodiment, a system consistent with the present disclosure may be configured to detect a fault in an electric power transmission system. The system may include a traveling wave detection subsystem configured to detect and measure traveling waves on a transmission line and a fault location estimation subsystem. The fault location estimation subsystem may receive from the traveling wave detection subsystem a first plurality of traveling waves on the transmission line generated during a reference event. The fault location estimation subsystem may receive from the traveling wave detection subsystem a second plurality of traveling waves generated during an unplanned event. An unmatched traveling wave in the second plurality of waves may be detected and a location of the unplanned event based on the unmatched traveling wave.