Abstract: Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period.

Abstract: This disclosure relates to detecting manipulation or spoofing of a time based on a latency of a communication system. In one embodiment, a system includes a time input to receive a time signal. The system includes a first interface to receive a first representation of a first condition at a first location at a first time and a second interface to receive a second representation of a second condition at a second location and at the first time. A latency determination subsystem may determine a latency based on a comparison of the time of arrival of the second measurement and the first time. A threshold subsystem may generate an indication of whether the latency satisfies a threshold. An anomalous condition subsystem may identify an anomalous condition based on the indication, and a remedial action may be implemented based on the anomalous condition.

Abstract: A system for accurately determining a location of a fault in an electric power delivery system using traveling waves by compensating for dispersion of the traveling waves. The dispersion may be calculated based on a preliminary fault location determination, and the arrival times of traveling wave peaks may then be corrected using the calculated dispersion. A compensation to the traveling wave propagation speed may be made using a proportionality factor to correct for traveling wave dispersion. Dispersion correction may be a function of fault type or physical power line conditions.

Abstract: The present disclosure relates to detection of faults in an electric power system. In one embodiment, an incremental quantities subsystem may be configured to calculate a plurality of values of an operating quantity based on the plurality of time-domain representations of electrical conditions. The incremental quantities subsystem may also calculate a plurality of values of a restraining quantity based on the plurality of time-domain representations of electrical conditions. An interval during which the calculated operating quantity exceeds the calculated restraining quantity may be determined. A fault detector subsystem may be configured to declare a fault based on the calculated operating quantity exceeding the calculated restraining quantity by a security margin. A protective action subsystem configured to implement a protective action based on the declaration of the fault.

Abstract: The present disclosure relates to detection of faults in an electric power system. In one embodiment, a time-domain traveling wave differential subsystem is configured to determine at a first terminal a first index between an arrival maximum of a traveling wave generated by a fault at the first terminal and an exit maximum of the traveling wave. The traveling wave subsystem also determines a second index between an arrival maximum of the traveling wave at the second terminal and an exit maximum of the traveling wave. An operating quantity and a restraint quantity may be determined based on a magnitude of the representations of electrical conditions in the first index and the second index. A fault may be declared based on a comparison of the operating quantity and the restraint quantity. A protective action subsystem may be configured to implement a protective action based on the declaration of the fault.

Abstract: 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.

Abstract: 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.

Abstract: A system for monitoring an electric power delivery system by obtaining high-frequency electric power system measurements and displaying event information is disclosed herein. The system may use the high-frequency electric power system information to detect traveling waves. The system may generate a display showing fault location on the electric power system, and timing of traveling waves received at locations on the electric power system. The display may include time on one axis and location on another axis. The display may include a waterfall display.

Abstract: Disclosed herein are systems for monitoring and protecting an electric power system using a plurality of conductor-mounted detectors (CMDs). In one embodiment, a plurality of CMDs are coupled to an electrical conductor. Each CMD may harvest power from the electrical conductor and may monitor electrical current in the conductor. When the electrical current in the conductor exceeds a fault current threshold a fault signal may be transmitted. A receiver in communication with each of the plurality of CMDs may receive the fault signal from at least one of the plurality of CMDs. A protective action may be generated and implemented to clear the fault. A portion of the electric power system affected by the fault may be determined based on identification of each of the plurality of CMDs to transmit the fault signal.

Abstract: Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period.

Abstract: The present disclosure relates to detection of faults in an electric power system. In one embodiment, a time-domain traveling wave directional subsystem is configured to receive a plurality of current traveling wave and a plurality of voltage traveling wave time-domain representations based on electrical conditions in the electric power delivery system. The plurality of current and voltage traveling wave time-domain representations may be compared to respective minimum thresholds. An integral may be generated based on a product of the plurality of current and voltage traveling wave time-domain representations when the current and voltage traveling wave time-domain representations exceed the minimum thresholds. A sign of the integral may reflect whether the fault is in the forward or reverse direction. A fault detector subsystem configured to declare the fault when the sign reflects that the fault is in the forward direction and the integral exceeds a security margin.

Abstract: The present disclosure relates to detection of faults in an electric power system. In one embodiment, an incremental quantities subsystem is configured to determine a forward torque, an operating torque, and a reverse torque based on the plurality of time-domain representations of electrical conditions. Each of the forward torque, the operating torque, and the reverse torque may be integrated over an interval. A fault detection subsystem may determine an occurrence of the fault based on a comparison of the operating torque to the forward torque and the reverse torque. Further, a direction of the fault may be determined based on the comparison of the forward torque, the operating torque, and the reverse torque. A fault may be declared based on the comparison and the direction. A protective action subsystem may implement a protective action based on the declaration of the fault.

Abstract: The present disclosure relates to detection of faults in an electric power system. In one embodiment, an incremental quantities subsystem may be configured to calculate a plurality of values of an operating quantity based on the plurality of time-domain representations of electrical conditions. The incremental quantities subsystem may also calculate a plurality of values of a restraining quantity based on the plurality of time-domain representations of electrical conditions. An interval during which the calculated operating quantity exceeds the calculated restraining quantity may be determined. A fault detector subsystem may be configured to declare a fault based on the calculated operating quantity exceeding the calculated restraining quantity by a security margin. A protective action subsystem configured to implement a protective action based on the declaration of the fault.

Abstract: The present disclosure relates to detection of faults in an electric power system. In one embodiment, a time-domain traveling wave differential subsystem is configured to determine at a first terminal a first index between an arrival maximum of a traveling wave generated by a fault at the first terminal and an exit maximum of the traveling wave. The traveling wave subsystem also determines a second index between an arrival maximum of the traveling wave at the second terminal and an exit maximum of the traveling wave. An operating quantity and a restraint quantity may be determined based on a magnitude of the representations of electrical conditions in the first index and the second index. A fault may be declared based on a comparison of the operating quantity and the restraint quantity. A protective action subsystem may be configured to implement a protective action based on the declaration of the fault.

Abstract: A testing system for imposing a traveling wave signal on an electric power system signal for testing a fault detector is disclosed herein. The testing system may be configured to simulate a fault at a simulated location by controlling the timing of the traveling wave signal. The testing system may be configured to impose multiple traveling wave signals to test the accuracy of the fault location determined by the fault detector. The testing system may be configured with multiple testing apparatuses using time coordination and referenced to an intended fault instant. The testing system may be configured to supply traveling waves of different polarities to test for different fault type detection.

Abstract: Disclosed herein are systems for monitoring and protecting an electric power system using a plurality of conductor-mounted detectors (CMDs). In one embodiment, a plurality of CMDs are coupled to an electrical conductor. Each CMD may harvest power from the electrical conductor and may monitor electrical current in the conductor. When the electrical current in the conductor exceeds a fault current threshold a fault signal may be transmitted. A receiver in communication with each of the plurality of CMDs may receive the fault signal from at least one of the plurality of CMDs. A protective action may be generated and implemented to clear the fault. A portion of the electric power system affected by the fault may be determined based on identification of each of the plurality of CMDs to transmit the fault signal.

Abstract: The present disclosure relates to detection of faults in an electric power system. In one embodiment, a time-domain traveling wave directional subsystem is configured to receive a plurality of current traveling wave and a plurality of voltage traveling wave time-domain representations based on electrical conditions in the electric power delivery system. The plurality of current and voltage traveling wave time-domain representations may be compared to respective minimum thresholds. An integral may be generated based on a product of the plurality of current and voltage traveling wave time-domain representations when the current and voltage traveling wave time-domain representations exceed the minimum thresholds. A sign of the integral may reflect whether the fault is in the forward or reverse direction. A fault detector subsystem configured to declare the fault when the sign reflects that the fault is in the forward direction and the integral exceeds a security margin.

Abstract: 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.

Abstract: Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period.

Abstract: Continuous monitoring of an electric power system during testing of a primary electric power meter is described herein. Electric power system signals or test signals may be selectively supplied to the primary electric power meter. Electric power system signals may be supplied to a secondary meter while a test signal is applied to the primary electric power meter. The secondary meter may record and/or transmit monitoring functions and communicate the results of the monitoring functions to the primary electric power meter while the test signals are supplied to the primary electric power meter.