The present invention discloses A method of single-phase-to-ground fault line selection for a distribution line based on the comparison of phase current traveling waves, comprising: sampling three phases current traveling waves on the distribution line, and taking the busbar pointing to the line as the current positive direction; when a single-phase-to-ground fault occurs on the distribution lines, comparing the amplitude and polarity of the difference between the three phases current traveling waves before and after the fault, wherein when the amplitude of one of the three phases current traveling wave is higher than 1.5 times of the amplitude of the other two phases current traveling waves, and the polarity of the one of three phases current traveling wave of the largest amplitude is opposite to the polarity of the other two phases current traveling waves, it is determined that the fault occurs on the load side of the measuring point of the line, and the phase with the largest amplitude of the current traveling wave is the fault phase; if the difference of the amplitudes of the three phases current traveling waves is within a predetermined value and the polarity is the same, it is determined that the fault occurs on the power source side of the measuring point of the line. By the technical solution of The present invention, the precise line selection of the single-phase ground fault of the distribution line can be realized.

A line double-end steady-state quantity distance measuring method and system based on an amplitude-comparison principle. According to the method and system, voltage values and current values of both sides of a line before and after a fault are collected (102), a voltage variable quantity and a current variable quantity of both sides of the line are calculated (103), and after a voltage phasor value and a current phasor value are determined according to the voltage variable quantity and the current variable quantity (104), the position of a short-circuit point is determined by performing iterative calculation on the voltage of the short-circuit point. The method is simple in principle, and can accurately recognize a fault point, achieving precise distance measurement of lines.

A drone deployable power line fault detection sensor. The sensor can include a clamp mechanism having a clamp ring with first and second ring portions movably connected to each other and a resilient member positioned to urge the first and second ring portions toward a closed configuration. A latch can be positioned to retain the first and second ring portions in an open configuration whereby the sensor can be positioned on a power transmission line with a drone. A trigger can be coupled to the latch and operative, under the weight of the sensor, to disengage the latch thereby releasing the first and second ring portions to close around the transmission line under the force of the resilient member. One or more sensors are carried by the clamp mechanism and positioned to detect a line fault on the power transmission line, which is reported to a power station control system to de-energize the power transmission line.

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.

A ring-shaped power supply system includes: a plurality of relays provided apart from each other on a ring-shaped power supply wire; a plurality of detectors, each provided between ones of the relays, for detecting an electrical change caused by a break when such a break has occurred in the ring-shaped power supply wire; and an arithmetic processor that localizes the point of the break in the ring-shaped power supply wire based on electrical changes detected by the plurality of detectors and cuts off ones of the relays located on both sides of the break point.

Methods, systems, and apparatus, including computer programs stored on a computer-readable storage medium, for obtaining, from an electric field sensor, measurements of a net electric field resulting from a combination of respective electric fields from two or more electrical power conductors that are proximate to the electric field sensor. The apparatus detects a change in successive measurements of the net electric field. The apparatus determines, based on the change, that an electrical fault has occurred in one of the two or more electric power conductors. The apparatus sends to a server system, data indicating that the electrical fault has occurred in one of the two or more electric power conductors.

This disclosure describes techniques implemented at least in part by a fuse-monitoring device to detect when a fuse cutout in an electric power system opens to disconnect a device and/or a load from a power line, and provides an indication of a location of the opened fuse cutout to a utility provider. The fuse-monitoring device may be attached to a fuse holder of the fuse cutout, and may include a movement sensor that detects when the fuse holder swings open due to its fuse melting, or blowing. The fuse-monitoring device may send a notification to the utility provider indicating that the fuse holder has swung open. The fuse-monitoring device may include a GPS sensor to determine the location of the fuse cutout, and may also notify the utility provider of the location of the fuse cutout so a line crew can quickly locate the fuse cutout that requires maintenance.

Receive analog signal representing real-time electrical current of electrical power transmission/distribution line; sample and digitise analog signal to generate power line current data; generate data frames of subsets of the power line current data for successive overlapping time slices, process data frames to generate frequency domain data representing frequency components for different frequency ranges; process frequency domain data to generate energy data representing average energies of frequency ranges over corresponding time slice; generate two-dimensional feature for machine learning, first dimension represents plurality of the successive time slices, second dimension represents different frequency ranges, values of the two-dimensional feature represent logarithms of corresponding average energies of frequency components of electrical current over corresponding time slices; apply deep learning classifier to two-dimensional feature to detect high-impedance fault in electrical power transmission/distribution line, and if detected: send fault signal to relay or circuit breaker to cut power to the electrical power transmission/distribution line.

A method for detecting fault in a power transmission line of a power transmission system and protection system using the same. The method includes: obtaining a system parameter of the power transmission system, adjusting protection reachability of a fault detecting element based on the obtained system parameter such that the adjusted protection reachability of the fault detecting element is applicable to a predetermined protection range, identifying whether there is an internal fault occurring on the transmission line using the adjusted fault detecting element, and generating a fault detection decision signal indicating the identified fault. If the predetermined protection range is desirable for the fault detecting element, its protection reachability may be adjusted in consideration of the influence imposed by the SIR such that the reach point of the adjusted fault detecting element can be extended to approach the end of the predetermined protection range. Consequently, the influence on its accuracy by various SIR values can be taken into account and accordingly the fault detecting solution can remove substantial errors as a result thereof.

The invention relates to protection from faults in a power transmission system having two or more transmission lines. Travelling waves are detected from a signal obtained with a measurement equipment associated with a bus of the power transmission system. Arrival times of a first peak of a first travelling wave, a second travelling wave and a third travelling wave, are detected from the signal. A value for line length is calculated from the arrival times and propagation velocity of the travelling wave in the corresponding transmission line. The calculated value is compared with an actual length of the corresponding transmission line, for determining if the fault is an internal fault or an external fault. According to the fault being one of the internal fault and the external fault, a signal for controlling a switching device associated with the corresponding transmission line is generated.