Method and apparatus for detecting in impedance change in a transmission line, such as a line in a computer bus. A CMOS-compatible time domain reflectometer circuit comprising a comparator is embedded in one or more chips and connected to the transmission line. The circuit measures the impedance inhomogeneity pattern (IIP) of the transmission line prior to use, and then repeatedly measures the HP during operation of the transmission line to detect a change in IIP, without Interfering with data transfer through the transmission line. The present invention can detect and locate wire-tapping magnetic probing or snooping, and Trojan and cold boot attacks on interconnecting buses between computer chips or integrated circuits in a computer system, such as on external memory buses.

A power distribution monitoring system is provided that can include a number of features. The system can include a plurality of power line sensing devices configured to attach to individual conductors on a power grid distribution network. The sensing devices can be configured to measure and monitor, among other things, current values and waveforms, phase voltage, conductor current, phase-to-phase voltage, conductor temperatures, ambient temperatures, vibration, wind speed and monitoring device system diagnostics. The sensing devices can include an equipotential surface configured to reduce incumbent E-field disturbance of the conductor. The sensing devices can include a monitor-device conductor shell sized and shaped to position the equipotential surface at a distance with respect to the conductor regardless of diameter of the conductor. Methods of installing and protecting the system are also discussed.

An exemplary unmanned aerial vehicle (UAV) mountable to a conductor of an aerial power transmission line system includes a body having a rotor system, a motivation system attached to the body to motivate the UAV along the conductor, a battery carried by the body and electrically connected to at least one of the rotor system and the motivation system, a monitoring tool mounted with the body and an inductive coil carried by the body and in electric connection with the battery, wherein the inductive coil is configured to harvest electricity from the aerial power transmission line system and charge the battery.

Methods for determining a line fault of a power system. The methods include obtaining sampled values of voltages and currents of phases of a power line in the power system, determining a phase compensation voltage of a first phase and an interphase compensation voltage of an interphase loop between a second phase and a third phase, and detecting the line fault in the first phase and/or the interphase loop by comparing the phase compensation voltage and the interphase compensation voltage.

A method of detecting self-clearing, sub-cycle faults comprises sensing a current condition and a voltage condition at a location along a power cable. The sensed conditions are relayed to an analyzing device, the analyzing device including a current peak detector. The presence of a measured current value is determined. If the measured current value is greater than a current threshold value, a faulted circuit indicator (FCI) analysis is performed to determine the presence or absence of an FCI fault. If an FCI fault is absent, an incipient fault analysis is performed, wherein the RMS current values before and after a threshold event are compared and the voltage total harmonic distortion (THD) before and after the event are compared. If the two current values are within a first predetermined percentage and the THD values differ by a second predetermined percentage, then an incipient fault is reported. If either the two current values are not within the first predetermined percentage or the THD values do not differ by at least the second predetermined percentage,

The invention enables an optical voltage sensor, comprising a piezoelectric actuator mechanically coupled to an optical strain sensor (such as a fibre Bragg grating), to withstand lightning impulses, the effects of which would otherwise be harmful or destructive to the piezoelectric actuator and/or other sensitive components. As such, the optical voltage sensor, comprised within a photonic voltage transducer which also comprises a lightning impulse attenuator, is able to comply with relevant standards and be used for applications in power networks and exposed to the highest voltages for equipment.

Unmanned monitoring devices, such as unmanned aerial vehicles (UAV), drones or rovers may inspect system components within an area of interest (AOI) such an electric power distribution system including generation, transmission, and distribution elements for autonomous detection of damage to the components. Work orders for repairing the damage are autonomously generated and resources identified within the work orders are autonomously provisioned.

A method of determining a fault in a protected zone of a power line comprises obtaining measurements at a measurement point at one end of the power line, processing the measurements in a number of parallel processing branches comprising at least two parallel processing branches, wherein the processing in each branch comprises filtering the measurements in a corresponding low pass filter for obtaining a corresponding set of filtered measurements, wherein the cut-off frequencies of the low pass filters in these parallel processing branches differ from each other, performing reach calculations on the filtered measurements for obtaining corresponding reach point quantities, and comparing the reach point quantities with corresponding thresholds. Finally, it is determined that there is a fault within the protected zone if any threshold is crossed.

A noise intrusion position estimation device includes: a measurement unit including a pair of detection units to simultaneously measure a temporal change of waveforms of noise on a transmission cable at two separated observation points in the transmission cable; and a calculation unit to receive, from the measurement unit a pair of the waveforms of the noise simultaneously measured, to time-reverse the pair of the waveforms of the noise that has been received, to perform transmission path analysis in which the two observation points are set as positions of signal sources of the time-reversed noise and the time-reversed waveforms are set as excitation waveforms in a transmission line model in which electrical characteristics of the transmission cable are represented, and to output a position of a peak value obtained from a result of the transmission path analysis as an intrusion position of the noise into the transmission cable.

Systems, apparatuses, methods, and computer program products are disclosed for predicting causes of changes in power loss along electric line segments. An example method includes receiving, by a control system, telemetry data from a set of devices in an electrical grid and storing, by the control system, the telemetry data in a memory. The example method further includes calculating, by the control system and using the telemetry data, a change in impedance in an electric line segment between two devices from the set of devices and determining, by the control system, a cause of the change in the impedance in the electric line segment between the two devices. Corresponding apparatuses and computer program products are also disclosed.