S&c Electric Company

Cooper Technologies Company

Mcgraw-edison Company

Stephen E Williams

Martin T Bishop

David G Porter

Ljubomir A Kojovic

Michael John Meisinger, Sr

Michael Meisinger

Thomas J Dyer

Joseph W Milton

Peter J Meyer

Andrew B Berman

Lauren Abramczyk

Veselin Skendzic

Sarjoun Skaff

Donald S Berkowitz

James W Sember

David Francis Klein

Marcelo Perez

Thomas Walker

Terrence Bellei

Juan Pablo Gonzalez

A device having a pulse catching function for detecting fault test pulses in an electrical power distribution network in response to a fault. The device includes one or more sensors for measuring current and/or voltage, where the device detects the pulses by loss of voltage followed by identifying one or more of a peak current magnitude of the pulses being greater than a predetermined current value, a pulse duration of the pulses being greater than a predetermined time, a predetermined interval between consecutive pulses and a presence of a pulse/inverse pulse sequence.

Pulse catching

An electrical power network employing fault location, isolation and system restoration. The system includes a plurality of switching devices electrically coupled along a power line downstream of a fault interrupting device. The switching devices each have current and voltage sensing capability and the capability to provide pulse tests for detecting fault presence. The fault interrupting device performs reclosing operations, and when the plurality of switching devices detect fault presence a predetermined number of times in coordination with reclosing operations performed by the fault interrupting device and detect loss of voltage, each switching device opens. The fault interrupting device closes when the switching devices open, and the switching devices sequentially pulse test and close from a furthest upstream switching device when detecting return of voltage and no fault presence until a switching device closest to the fault pulse tests and detects fault presence and locks open.

Transmission line fault location, isolation and system restoration (FLISR) system

A system and method for determining when an electronic interrupting device will open in response to detecting overcurrent, where the interrupting device protects a transformer in a power distribution network. The method includes obtaining a time/current through fault protection curve that is defined by a plurality of time/current points for the transformer that identifies when the transformer may experience thermal or mechanical damage in response to a certain current flow over a certain time in the transformer windings, selecting a time multiplier, and determining an operating curve for the interrupting device by multiplying the multiplier and a time portion of each of the plurality of time/current points on the through fault protection curve, where the operating curve identifies when the interrupting device will open in response to a certain current flow over a certain time.

Transformer overcurrent protection

A system and method for identifying an earth fault in a resonant grounded medium voltage network that employs a REFCL compensation system. The method derives a zero-sequence real power from a phase voltage to ground on each phase and a current on each phase and aligns the zero-sequence real power in time with a magnitude of a zero-sequence voltage provided by the REFCL compensation system. The method determines when the zero-sequence real power and the zero-sequence voltage exceed predetermined thresholds. The method delays the magnitude of the zero-sequence voltage for a predetermined period of time when the zero-sequence voltage exceeds the threshold and determines that the fault is occurring when both the time aligned zero-sequence real power exceeds the threshold and the magnitude of the zero-sequence voltage exceeds the threshold for the predetermined period of time at the same time.

Earth fault sectionalizer for electric power distribution network

A power restoration system comprising a feeder, a plurality of power sources available to provide power to the feeder, a plurality of normally closed reclosing devices electrically coupled along the feeder, at least one normally open recloser electrically coupled to the feeder, and a plurality of normally closed switches electrically coupled along the feeder between each adjacent pairs of normally closed reclosing devices. Each switch is assigned a position code having a value for each of the plurality of power sources that determines when the switch will open in response to the fault current and which power source the switch is currently receiving power from, where timing control between the reclosing devices and the switches allows the switch to be selectively opened to isolate the fault within a single feeder section between each pair of adjacent switches or between each switch and a reclosing device.

Utility distribution fault restoration system

A power restoration system for restoring power to feeder segments in response to a fault. The system includes a reclosing device having a switch and one or more sensors for measuring current and/or voltage on the feeder, where the reclosing device performs a pulse testing process to determine circuit fault conditions. The system also includes a plurality of switching devices electrically coupled along the feeder, where each switching device includes a section switch and one or more sensors for measuring current and/or voltage on the at least one feeder. In one embodiment, each switching device recognizes predetermined pulse codes having a sequence of pulses, where the reclosing device uses the pulse testing process to generate and selectively transmit defined pulse codes on the feeder that selectively cause the section switches to change states between an open state and a closed state depending on the code.

Sectionalizing using coded pulses and pulse testing

A method for performing a low energy pulse testing in a power distribution network that causes contacts to close and then open in about one fundamental frequency cycle of current flow time and close on a voltage waveform that produces symmetrical fault current. The method includes energizing a magnetic actuator to move the actuator against the bias of a spring to move a movable contact towards a fixed contact. The method also includes de-energizing the actuator when the movable contact makes contact with the fixed contact so as to allow the spring to move the movable contact away from the fixed contact so that the amount of time that the current conducts is about one fundamental frequency cycle of the current, where energizing the magnetic actuator occurs when an applied voltage on the switch assembly is at a peak of the voltage wave so that the current is symmetric.

Low energy reclosing pulse test

A control system and method for sectionalizing switches and pulse-testing interrupter/reclosers in a distribution grid feeder which enables fault location, isolation and service restoration without requiring an external communications infrastructure to pass information between the switches. The method includes switches entering an armed state when they experience a high fault current during an initial fault event. Then, when the interrupter/recloser runs its test pulse sequence, any armed switch counts all test pulses as fault pulses, while non-armed switches count the test pulses as load pulses. Switches open to isolate the fault based on threshold values of fault pulse count and load pulse count. When an initially active interrupter/recloser completes its test pulse sequence, another interrupter/recloser begins its sequence, and all switches reconfigure their threshold values based on the new interrupter/recloser. Interrupter/reclosers after the initial device use a fast close-open event if necessary to arm some switches for proper fault-count opening.

Locating and isolating grid faults utilizing a fast close-open operation

An energy storage system comprising a main bus, a transfer bus, and a pair of anti-parallel thyristors electrically coupled to the main bus and the transfer bus. The system also includes a first and second group of battery cells electrically coupled to the main bus and the transfer bus, and a switching network including a plurality of switches that selectively connect the first and second groups of battery cells to the main bus and the transfer bus. A controller controls the position of the switches and a bias voltage applied to the first and second thyristors so as to seamlessly transition power from the first group of battery cells to the second group of battery cells when the group of battery cells are being discharged and seamlessly transition power between the first group of battery cells and the second group of battery cells when the battery cells are being charged.

System and method for closed-transition transfer of DC battery banks on a grid scale battery energy storage system

This patent describes embodiments of systems, apparatus and methods to provide improved control and coordination of a multiplicity of electric distribution grid-connected, energy storage units deployed over a geographically-dispersed area.

Distributed energy storage system and method of distributing energy

A method for detecting a voltage disturbance in a utility having a micro-grid. The method transforms current and voltage measurements into first and second voltage values and first and second current values in a stationary reference frame, and transforms the first and second voltage values and the first and second current values to third and fourth voltage values and third and fourth current values in a rotating reference frame, where the third voltage value defines an average magnitude of the three-phase power signals. The method multiplies the third current value by the third voltage value to obtain an instantaneous power value and multiplies the fourth current value by the third voltage value to obtain an instantaneous volt-ampere reactive (VAR) value. The method opens the switch if the VAR value has a magnitude above a predetermined value and a direction indicating the fault is outside of the micro-grid in the network.

Method to detect utility disturbance and fault direction

Relay devices, systems and methods for obtaining an accurate representation of a current monitored with a Rogowski coil, without integration of the Rogowski coil output voltage signal in the time domain.

Growing community of inventors

Franklin, WI, United States of America

Stephen E Williams