Systems and methods are provided herein for improving distance protection in transmission lines. Such systems and methods may involve receiving one or more current and voltage inputs, and determining, based on the one or more current and voltage inputs, one or more current and voltage phasors, wherein the one or more current and voltage phasors are determined using a short window phasor estimation. Such systems and methods may also involve determining, within a single power cycle and based on the one or more current and voltage phasors, a fault in a transmission line. Such systems and methods may also involve sending, to a distance protection element and based on the determination that the fault exists, a signal to clear the fault in the transmission line, and clearing the fault in the transmission line.

The present subject matter describes fault detection during power swing in a power transmission system. Voltage and current measurements are obtained for each phase at a terminal of the power transmission system. Based on measurements obtained, a value of change in an impedance angle for each phase-to-ground loop and each phase-to-phase loop for each sampled value of voltage and current is calculated, where the value of change in the impedance angle is a difference between impedance angles of two samples separated by a predetermined interval. Further, the average values for change in impedance angle based on a predetermined number of values of the change in the impedance angle for each phase-to-ground loop and each phase-to-phase loop is calculated. The average values calculated are compared with a threshold of change in impedance angle and based on the comparison a fault in one or more of the phase-to-ground loops or phase-to-phase loops is detected and classified.

In one embodiment, a network protector for a spot network includes a circuit breaker and a network protector relay coupled to the circuit breaker. The network protector relay is structured and configured to have network protector relay non-sensitive trip settings for controlling operation of the circuit breaker that will cause the network protector to remain closed when: (i) an angular difference (±) between a transformer phase-to-neutral voltage of the first feeder branch and a transformer phase-to-neutral voltage of the second feeder branch is less than or equal to a first threshold value, and (ii) a magnitude difference (±) between the transformer phase-to-neutral voltage of the feeder branch and the transformer phase-to-neutral voltage of the second feeder branch is less than or equal to a second threshold value.

A circuit interruption apparatus, for an electrical network, comprising a circuit interruption device that is operatively connectable at a source side to a source of the electrical network and at a back side to a load of an electrical network. The circuit interruption device when closed permits and when open inhibits the current flow between the source side the back side,. The current interruption device is configured to open when a current flowing therethrough meets or exceeds a fault current threshold. The circuit interruption apparatus also includes a fault current level determination unit that is configured to determine a predicted fault current level as a function of measured current and voltage values at the circuit interruption device before and after a variation in the current and voltage values at the circuit interruption device that result from a change of load at the back side of the circuit interruption device.

A system and method for detecting and localizing excess voltage drop in single or multiple phases of three-phase AC circuits is disclosed. An electrical distribution circuit is provided that includes an input connectable to an AC source, an output connectable to terminals of an electrical machine, the output configured to provide three-phase voltages and currents to the electrical machine, and a diagnostic system configured to detect an excess voltage drop (EVD) in the electrical distribution circuit. The diagnostic system includes a processor that is programmed to receive measurements of the three-phase voltages and currents provided to the electrical machine, compute a negative sequence voltage from the three-phase voltages and currents, determine a localization reference phase angle for each phase based in part on the three-phase voltages and currents, and calculate an EVD in the electrical distribution circuit based on the negative sequence voltage and the localization reference phase angles.

Disclosed an electricity amount detection method and device, a terminal and a storage medium. The method includes that: Identity (ID) information of each function device called by an application is acquired according to ID information of the application; a power consumption parameter generated when each function device is called is correspondingly acquired according to the ID information of each function device called by the application; a power consumption parameter generated when the application is running is determined according to the power consumption parameter generated by each function device; and the power consumption parameter generated when the application is running is output as a power consumption index when the application is running.

The method for determining mutual voltage sensitivity coefficients between a plurality of measuring nodes of an electric power network does not rely on knowledge of the network parameters (for example: series conductance and susceptance of the branches, shunt conductance and susceptance of the nodes, etc.). The method uses a monitoring infrastructure including metering units at each one of the measuring nodes, and includes a step of measuring at the same time, at each one of the measuring nodes, repeatedly over a time window, sets of data including values of the current, the voltage, and the phase difference, a step of computing active power, reactive power and values from each set of measured data, and a step of performing multiple parametric regression analysis of the variations of the voltage at each one of the measuring nodes.

Systems and methods may be used to determine fault types and/or directions even during a loss of potential by receiving, at one or more processors, an indication of a pre-fault power flow direction for a power delivery system. The one or more processors then determine a fault direction during a fault for the power delivery system using current vector angles and the pre-fault power flow direction.

A network protector includes a resettable switching apparatus configured to electrically connect to a low-voltage feeder of a secondary distribution network; a switch control configured to control a state of the resettable switching apparatus to thereby determine whether electrical current flows through the switching apparatus; and a controller configured to: determine whether a fault condition exists; and if a fault condition does not exist, allow electrical power to flow through the resettable switching apparatus in any direction.

Disclosed are a power interruption method and a power interruption device based on power phase measurement and arc detection and a method thereof and disclosed are a power interruption method and a power interruption device which accurately determine, when a value measured by a current transformer (CT), a voltage detector, etc., is input into the main control unit, whether the measured value is a value equal to or more than a predetermined threshold through a comparison between phases of voltage and current to effectively prepare for a disaster such as preventing fire or protecting a subsequent circuit by a rapid and accurate power interruption by arc at a load side.