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.

Phase selection for traveling wave fault detection systems is disclosed herein. Intelligent electronic devices (IEDs) may be used to monitor and protect electric power delivery systems by detecting and acting upon traveling waves. A phase of the electric power delivery system may be selected based on the relative polarity of the traveling waves detected. The amplitude and/or polarity of the selected phase may be compared with the amplitudes and/or polarities of the other phases to determine a fault condition. For instance, the IED may determine a single-phase-to-ground fault based on the relative polarities and magnitudes of the detected traveling waves, send a protective action to the identified faulted phase, and/or continue to monitor the system for a continuation of the event or identification of a different event, such as a three-phase fault, using incremental quantities.

Methods and arrangements for localizing an outage in a power grid. An outage is detected in a power grid, the power grid including interconnected nodes. At least one candidate network topology (in the power grid) with respect to the outage is determined, and power consumption information and measured voltages relative to the nodes in the power grid are received. Voltage at a plurality of the nodes in the power grid is estimated based on the received power consumption information and on the at least one candidate network topology, and a location of the outage is estimated, based on the estimated node voltages and measured voltages. Other variants and embodiments are broadly contemplated herein.

Systems and methods for identifying a fault condition in an Ungrounded Electrical Distribution (UED) system, the system receives measurements with instantaneous values and effective values associated when a fault event is identified, measured transient waveforms and a fault type. A processor applies an empirical mode decomposition to the measured transient waveforms to extract a dominant vibration mode and an associated derived waveform corresponding to the dominant vibration mode. A Hilbert transform is applied to the associated derived waveform to obtain a set of feature attributes. Subsets are computed from the set, at a pre-fault time, at a fault inception time, and at a post-fault time, and inputted into the fault type trained neural network model. An output of the model are locational parameters used to determine a fault section, a fault line segment and a fault location point with a topology connectivity analysis of the UED system.

A device for compensating a line fault occurring on a three-phase power supply grid includes a transformer with a neutral point which is designed to generate a network voltage and thus a neutral-point displacement voltage. A measurement and control device is configured to detect the network voltage or the neutral-point displacement voltage and on that basis to identify an occurring line fault and to determine a control variable for compensating the line fault. A converter circuit is configured to generate a control current from the control variable and to feed in the control current at the neutral point of the transformer to compensate the line fault. The measurement and control device is also configured to determine a boost line value, and on that basis to determine a boost function, to generate a corresponding boost current, and to feed same in at the neutral point of the transformer.

A method analyzes a fault of an ungrounded power distribution system. The method determines a type of a fault in a line segment of the ungrounded power distribution system, and modifies a nodal admittance matrix of the line segment determined before the fault using a transformation matrix corresponding to the type of the fault to produce a faulty nodal admittance matrix of the line segment after the fault. The ungrounded power distribution system is analyzed using the faulty nodal admittance matrix and nodal admittance matrices of functional branches or line segments of the power distribution system.

Systems and methods performed by a fault detection apparatus for fault detection and localization in distribution feeders having branches and nodes. The method including receive feeder raw data in a feeder of a power system. Process the feeder raw data with given operational electrical characteristics of the feeder to generate a branch attribute dataset for each branch separated by a pair of nodes for all branches. Generate a node attribute dataset for each node for all the nodes in the feeder. Input the branch and node attribute datasets into a trained neural network to determine whether a branch has a fault and a fault location within the branch, to output a classification of the fault and the fault location. Generate an alert signal based upon determining the classified fault and fault location in response to the alert signal to an outage response system.

A method for generating an error signal indicating an error type of an error in a multi-phase electrical energy supply network. Measured values describe a current operating state of the network. The measured values are transmitted to a protection device. An evaluating device evaluates every possible loop of the network that can be affected with respect to the recognition of the error type of an error, by using the measured values. In order to be able to more reliably recognize the error type even under different network conditions, the measured values and/or values derived from the measured values are evaluated using at least two different protection criteria, for every possible loop. Each of the protection criteria is suitable for indicating an error type of an error present in the evaluated loop, and the error signal is generated in consideration of all available evaluation results of the protection criteria.

A method for a faulted line identification in a power network, including, at a generic time-instant, solving a plurality of parallel phasor measurement units based real-time state estimators, the state estimators having among each other different and augmented network topologies, each of the augmented network topologies comprises an original network topology, which includes a plurality of real buses and real lines forming a connected graph mapping the real network topology, and a single additional virtual bus located along one of the real lines, the line in which the virtual bus is located has to be different for each of the augmented network topologies.

A system to identify potential faults in an electrical power distribution system includes a vibration monitor configured to detect a vibration event proximate a portion of the electrical power distribution system, a power quality monitor configured to detect a power quality event in a portion of the electrical power distribution system, an analysis system configured to correlate the vibration event detected by the vibration monitor with the power quality event detected by the power quality monitor, and an output configured to receive information regarding the power quality event from the analysis system and to provide the information to an operator.