Schweitzer Engineering Laboratories, Inc. Patent applications |
Patent application number | Title | Published |
20150312023 | Time Signal Propagation Delay Correction - Disclosed herein are a variety of systems and methods for correcting for propagation delay in time signals used in connection with an electric power generation and delivery system. According to various embodiments, a device consistent with the present disclosure may determine an estimated propagation delay between an accurate time source and a receiving device. The propagation delay may be determined based on a variety of transmission parameters including, for example, communication channel type and/or length. A corrected time signal may be generated by advancing a reference incitation such as an “on-time” reference and/or “start-of-second” reference included in the time signal by an amount associated with the propagation delay. The corrected time signal may then be transmitted to the receiving device. | 10-29-2015 |
20150311714 | Resilient Communication for an Electric Power Delivery System - A system for resiliently monitoring an electric power delivery system may include a plurality of server intelligent electronic devices (IEDs) configured to monitor and/or control the electric power delivery system. Each server IED may be communicatively coupled to a client control system by a plurality of communication paths. If a communication path fails, communication may continue along another path. In an embodiment, the client control system may include dual primary client controllers that continually request information from the server IEDs using multiple of the communication paths. The client controllers may request information from each other if the information is not received from the server IEDs, for example, due to a communication failure. In an embodiment, the client control system and server IEDs may be communicatively coupled in a loop topology, and each direction around the loop may be a distinct communication path. | 10-29-2015 |
20150276877 | Electric power system circuit breaker trip diagnostic - Disclosed herein are various systems and methods for monitoring the health of a circuit breaker. In various embodiments, a system may receive a voltage measurement across a trip coil assembly associated with a circuit breaker. The system may further receive a current measurement through the trip coil assembly. A plurality of transition points may be identified based on at least one of the voltage measurement and the current measurement, the plurality of transition points corresponding to at least one of a mechanical characteristic and an electrical characteristic of the circuit breaker during a trip event. A predictive analysis may be performed based at least in part on the plurality of transition points. An indication of the predictive health may be displayed. | 10-01-2015 |
20150244171 | Topology Determination Using Graph Theory - Disclosed herein are a variety of systems and methods for management of an electric power generation and distribution system. According to various embodiments, a system consistent with the present disclosure may be configured to analyze a data set comprising a plurality of generator performance characteristics of a generator at a plurality of operating conditions. The performance characteristics may be used to produce a generator capability model. The generator capability model may comprise a mathematical representation approximating the generator performance characteristics at the plurality of operating conditions. The system may further produce an estimated generator capacity at a modeled condition that is distinct from the generator performance characteristics of the data set and is based upon the generator capability model and may implement a control action based on the estimated generator capacity at the modeled condition. | 08-27-2015 |
20150244170 | Power System Management - Disclosed herein are a variety of systems and methods for management of an electric power generation and distribution system. According to various embodiments, a system consistent with the present disclosure may be configured to analyze a data set comprising a plurality of generator performance characteristics of a generator at a plurality of operating conditions. The performance characteristics may be used to produce a generator capability model. The generator capability model may comprise a mathematical representation approximating the generator performance characteristics at the plurality of operating conditions. The system may further produce an estimated generator capacity at a modeled condition that is distinct from the generator performance characteristics of the data set and is based upon the generator capability model and may implement a control action based on the estimated generator capacity at the modeled condition. | 08-27-2015 |
20150241894 | Contingency-Based Load Shedding - Disclosed herein are a variety of systems and methods for management of an electric power generation and distribution system. According to various embodiments, a system consistent with the present disclosure may be configured to analyze a data set comprising a plurality of generator performance characteristics of a generator at a plurality of operating conditions. The performance characteristics may be used to produce a generator capability model. The generator capability model may comprise a mathematical representation approximating the generator performance characteristics at the plurality of operating conditions. The system may further produce an estimated generator capacity at a modeled condition that is distinct from the generator performance characteristics of the data set and is based upon the generator capability model and may implement a control action based on the estimated generator capacity at the modeled condition. | 08-27-2015 |
20150088444 | Monitoring Synchronization of a Motor Using Stator Current Measurements - Monitoring synchronization of an electric motor using current signals from power supplied to the motor is disclosed herein. The current signals may be used to calculate representative current values which may be used to calculate a rotational frequency of the rotor of the motor. The rotational frequency may be used to determine synchronization, such as slip. Monitoring may be during startup of a synchronous motor in induction mode. Upon reaching a predetermined synchronization threshold, the motor may be configured from induction mode to synchronous mode. | 03-26-2015 |
20150043697 | Delay Compensation for Variable Cable Length - The present application discloses a time distribution device capable of providing a synchronized time signal to a plurality of end devices connected to the time distribution device with cables of various lengths. The time distribution device may receive a time signal, generate a time reference based on the received time signal, compensate the time reference for hardware delay, and overcompensate the time reference for a delay caused by a maximum cable length. Prior to being distributed to various end devices, each being connected with the time distribution device by cables of varying length, this overcompensated time reference may then be delayed by an amount based on the cable length connecting each respective end device such that the arrival of each of the synchronized time references at the various end devices is synchronized. | 02-12-2015 |
20150035681 | Point-to-Multipoint Polling in a Monitoring System for an Electric Power Distribution System - An automation controller may wirelessly poll a plurality of remote monitoring devices configured to monitor an electric power distribution system and store monitored system data collected therefrom. The automation controller may be wirelessly coupled to the plurality of remote monitoring devices using a spread-spectrum protocol, such as Bluetooth®. The automation controller may gather the monitored system data using the Distributed Network Protocol (DNP3). DNP3 packets may be communicated as the payload of Bluetooth® packets. The spread-spectrum protocol may limit the number of devices to which the automation controller may be actively connected at one time. Accordingly, the automation controller may couple and uncouple from the remote monitoring devices in a round-robin pattern to collect the monitored system data from all of the remote monitoring devices. The automation controller may provide engineering access and/or collect relay event data using the spread-spectrum protocol and a high-bandwidth protocol. | 02-05-2015 |
20140351572 | Automatically Configurable Intelligent Electronic Device - Disclosed herein are intelligent electronic devices configured for monitoring an electric power delivery system and for determining a plurality of configuration settings based on measurements from the electric power delivery system. An IED may identify a configuration event, obtain a plurality of electrical parameters associated with the configuration event, determine a plurality of configuration parameters from the electrical parameters, determine a plurality of configuration settings based on the configuration parameters, and apply the settings to the IED. The IED may also be configured to initiate the configuration event by opening a single pole of a multi-phase power line. | 11-27-2014 |
20140328441 | Synchronized Clock Event Report - The present application discloses monitoring a plurality of time inputs to detect a defined time event and providing a report of the plurality of time inputs for analysis in response to detecting the defined time event. To create the report, an event monitor records data relating to the plurality of time inputs in a temporary memory for a defined window of time. In response to detecting the defined time event, the event monitor transfers the data recorded in the temporary memory to a persistent memory and continues to record data relating to the plurality of time inputs to the persistent memory for a second defined window of time. The event monitor provides a report of the data relating to the plurality of time inputs stored in the persistent memory for analysis. | 11-06-2014 |
20140327574 | Multi-Constellation GNSS Integrity Check for Detection of Time Signal Manipulation - The present application discloses detecting manipulation of GNSS signals using a second time source. If two or more GNSS constellation signals are being detected, the phase error between the GNSS constellation signals may be monitored. When the phase error drifts, then manipulation is determined. The integrity of a GNSS constellation signal may be monitored using an internal time source such as a crystal oscillator by monitoring a slope of the free running counter at the detected rising edges of a pulse-per-second signal from the GNSS constellation. If more than two GNSS constellations are monitored, a voting scheme may be used to determine the manipulated GNSS constellation. | 11-06-2014 |
20140293494 | Adaptive Topology Assisted Protection and Control of Electric Power Delivery Systems - Disclosed are adaptive communication assisted protection and control. Local intelligent electronic devices (IEDs) associated with local switching devices and having unique IDs may transmit switch status and unique IDs to an area IED. The area IED may calculate topology using switch status, and provide control information to local IEDs using the topology. The area IED may communicate the unique ID of the local IED calculated to be immediately upstream of each local IED and, upon detection of a fault, the local IEDs may send blocking signals that include the received unique ID of the IED immediately upstream therefrom. The area IED may communicate control commands that include the unique IDs and control commands for the local IEDs to take the control action. Upon matching of the unique ID in the control command with its own unique ID, the local IEDs may take the control action and transmit remaining actions. | 10-02-2014 |
20140282021 | Visualization of Communication Between Devices in an Electric Power System - Systems and methods are presented for visualizing various devices in an electric power generation and delivery system. In certain embodiments, a method for visualizing communication may include receiving configuration information from an electric power generation and delivery system. Based on the configuration information, a plurality of devices included in the electric power generation and delivery system may be identified. Further, a plurality of communication pathways may be identified. Based on the identified plurality of devices and communication pathways, a visual topology of the electric power generation and delivery system may be generated and displayed. | 09-18-2014 |
20140280714 | Mixed-Mode Communication Between Devices in an Electrical Power System - Systems and methods are presented for facilitating mixed-mode communication between stations in an electric power generation and delivery system. In certain embodiments, a method for facilitating mixed-mode communication between a first device configured to communicate according to a first communication protocol and a second device configured to communicate according to a second communication protocol is presented The method may include installing a network device in a communication channel between the first device and the second device. A communications interface of the network device may be configured to receive messages from the first device and the second device. A message reconfiguration system of the network device may be configured to reconfigure messages received by the network device from the first device to reconfigured messages for transmission to the second device. | 09-18-2014 |
20140280713 | Proxy Communication Between Devices in an Electrical Power System - Systems and methods for exchanging messages between network devices and intelligent electronic devices of the electric power generation and delivery system are disclosed herein. In certain embodiments, a method performed by a network device for managing the exchange of messages between a first intelligent electronic device (IED) and a second IED included in an electrical power generation and delivery system may include receiving one or more messages configured according to a first communication protocol from the first IED. Based on information regarding one or more communication capabilities of the second IED, a second communication protocol may be determined. The message be reconfigured according to the second communication protocol to generate at least one reconfigured message. The reconfigured message may then be transmitted to the second IED. | 09-18-2014 |
20140280712 | Exchange of Messages Between Devices in an Electrical Power System - Systems and methods are presented for exchanging messages between devices in an electrical power generation and delivery system. In certain embodiments, a method for exchanging messages between devices may include transmitting messages included in a message stream that includes multiple redundant copies of the messages. An indication may be received that at least one message of the message stream was received by an intended receiving device. Transmission of further redundant copies of the message included in the message stream may be determined based on receipt of the indication. | 09-18-2014 |
20140280673 | SYSTEMS AND METHODS FOR COMMUNICATING DATA STATE CHANGE INFORMATION BETWEEN DEVICES IN AN ELECTRICAL POWER SYSTEM - Systems and methods are presented for managing communication between devices in an electric power generation and delivery system. In certain embodiments, a method for managing communication messages performed by a network device included in an electric power generation and delivery system may include receiving a message including an identifier and data state information via a communications interface. A determination may be made that that the message represents a data state change associated with the identifier. The message may be stored in a message buffer associated with the identifier. Finally, the stored message may be transmitted from the message buffer to an intelligent electronic device. | 09-18-2014 |
20140280672 | Systems and Methods for Managing Communication Between Devices in an Electrical Power System - Systems and methods for managing communication between devices in an electric power generation and delivery system are disclosed. In certain embodiments, a method for managing communication between devices may include receiving a message including an identifier via a communications interface. In certain embodiments, the identifier may identify a particular publishing device. A determination may be made whether the message is a most recently received message associated with the identifier. If the message is the most recently received message, the message may be stored message in a message buffer associated with the identifier, and transmitted from a device using a suitable queuing methodology. | 09-18-2014 |
20140269736 | Transmission of Data Over a Low-Bandwidth Communication Channel - Disclosed herein are various systems and methods that may improve the transmission of data over low-bandwidth communication channels in an electric power delivery system. Devices communicating across a low-bandwidth communication channel may implement several approaches, according to various embodiments disclosed herein, to reduce the data transmitted across the low-bandwidth communication channel and to prioritize the transmission of time-sensitive and/or more important information with respect to other data. Various embodiments disclosed herein may inspect packets to be transmitted across a low-bandwidth communication channel in order to identify high priority data. High priority data may be time-sensitive information, and accordingly, transmission of such data may be prioritized over other data in order to reduce transmission latency of the higher priority data. | 09-18-2014 |
20140253146 | Electrical Test Switch - Disclosed herein are various embodiments of electrical test switches. According to one embodiment, a test switch may include a switch lever, a test port configured to directly couple to a standard connector, a relay port, a field port, and an insulated frame configured to electrically insulate at least some electrically conductive portions of the test port, the relay connector, and the field connector from contact by a user. A user may actuate the switch lever in order to reconfigure the electrical test switch from a first configuration to a second configuration. In the first configuration, the test port contact is electrically isolated from the relay connector and the field connector is electrically connected to the relay connector. In the second configuration, the test port contact is electrically connected to the relay connector and the relay connector is electrically isolated from the field connector. | 09-11-2014 |
20140251478 | Automation of Water Flow in Networks - Disclosed is a control system for a water network. The control system includes a plurality of remotely-located monitoring and or monitoring and automatic control stations each including an automation controller for local control and automation, and each in communication via a dual-ring communication topology for system or wide-area control. The dual-ring facilitates redundant peer-to-peer data exchange to provide upstream and downstream water flow and water quality information. Systems described herein may calculate flow differential based on water flow data from each of the monitoring stations, and control flow based on the calculated flow differential. | 09-11-2014 |
20140250972 | Quality of Precision Time Sources - Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period. | 09-11-2014 |
20140247185 | Detection of Manipulated Satellite Time Signals - Disclosed herein is a system for detecting manipulation of a GNSS signal and mitigating against such manipulation. A GNSS receiver receives GNSS signals from a plurality of GNSS satellites, and calculates event times for each GNSS satellite. The GNSS receiver then compares a next event time for a particular GNSS satellite with an expected next event time for the particular GNSS satellite. If the difference between the expected next event time and the next event times exceeds a predetermined threshold, then the GNSS receiver indicates that signal integrity may be compromised. | 09-04-2014 |
20140244058 | State Trajectory Prediction in an Electric Power Delivery System - Disclosed is state trajectory prediction in an electric power delivery system. Electric power delivery system information is calculated from measurements by intelligent electronic devices (IEDs), and communicated to a state trajectory prediction system. The state trajectory prediction system may be configured to generate a load prediction profile. The load prediction profile may provide a predicted response of a load at a future time. Further, the state trajectory prediction system may be configured to generate a generator prediction profile that provides a predicted response of a generator at a future time. The state trajectory prediction system may generate a state trajectory prediction based, at least in part, on the load prediction profile and the generator prediction profile. The state trajectory prediction may represent a future state of the electric power delivery system. | 08-28-2014 |
20140211624 | Network Device - Disclosed is a network communication switch that facilitates reliable communication of high priority traffic over lower priority traffic across all ingress and egress ports. The network communication switch may monitor the frame storage buffer regardless of egress port, and when the frame storage buffer reaches a predetermined level, the switch may discard lower priority frames from the most congested port. When the frame storage buffer reaches a second predetermined level, the switch may discard lower priority frames before they are stored according to egress port. The network communication switch may further monitor ingress frames for priority, and assign priority to frames according to pre-assigned priority, ingress port, and/or frame contents. | 07-31-2014 |
20140191591 | Preventing Out-of-Synchronism Reclosing Between Power Systems - The present disclosure provides apparatus, systems, and methods for preventing out-of-synchronism closing between power systems. An intelligent electronic device (IED) apparatus may include a control component and a delay component. The control component is configured to selectively control opening and closing of a breaker. The control component selectively outputs a close signal to cause the breaker to connect a first portion of a power delivery system to another portion of the power delivery system. The delay component is configured to delay output of the close signal to the breaker. The delay component includes circuitry independent from control by the control component and the delay component is inconfigurable from a remote location. | 07-10-2014 |
20140128999 | Recording of Operating Parameters of an Intelligent Electronic Device - The present disclosure provides systems and methods for recording operating parameters of an intelligent electronic device (IED). A system may include a parameter acquisition module, a parameter storage module, and a memory management module. The parameter acquisition module may be configured to periodically obtain operating parameters of an IED at a first interval. The first interval may have a first time length to provide a first resolution of operation of the IED. The parameter storage module may be configured to store the operating parameters. The memory management module may be configured to delete, outside a first resolution period, a first portion of the operating parameters while maintaining a second portion of the operating parameters. The second portion may include operating parameters for each of a second interval. The second interval may have a second time length to provide a reduced second resolution of the operation of the IED. | 05-08-2014 |
20140114731 | Voting Scheme for Time Alignment - Systems and methods for time aligning time-stamped measurements using a voting scheme are disclosed. The system and method filter incoming measurements based on whether the time-stamped measurements fall within a defined time window. In response to determining that the time stamp falls within the defined time window, the time-stamped measurement is added to a time slice corresponding with the time stamp. In response to determining that the time-stamped measurement does not fall within the defined time window, the time window is re-established based on a voting scheme. | 04-24-2014 |
20140114608 | Time Distribution with Multi-Band Antenna - Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period. | 04-24-2014 |
20140111377 | Manipulation Resilient Time Distribution Network - Disclosed herein is a system for detecting manipulation of a global time source such as a Global Navigational Satellite System (GNSS) signal and mitigating against such manipulation. A plurality of receivers with geographical diversity receive GNSS signals, and calculate a time signal to be distributed to consuming devices. The receivers also communicate calculated time signals with other receivers. The receivers compare the time signals, and when a difference between the time signals exceeds a predetermined threshold, the receivers indicate that manipulation is likely. Such indication is shared across the network of receivers. The indication is further shared with consuming devices of the time signal from the compromised receiver. A second time signal that is not compromised may be shared with the consuming devices and/or used by the consuming devices. The consuming devices may modify their behavior when in receipt of the indication. | 04-24-2014 |
20140111249 | Time Distribution Switch - Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period. | 04-24-2014 |
20140109182 | DETECTION AND RESPONSE TO UNAUTHORIZED ACCESS TO A COMMUNICATION DEVICE - A communication gateway consistent with the present disclosure may detect unauthorized physical or electronic access and implement security actions in response thereto. A communication gateway may provide a communication path to an intelligent electronic device (IED) using an IED communications port configured to communicate with the IED. The communication gateway may include a physical intrusion detection port and a network port. The communication gateway may further include control logic configured to evaluate physical intrusion detection signal. The control logic may be configured to determine that the physical intrusion detection signal is indicative of an attempt to obtain unauthorized access to one of the communication gateway, the IED, and a device in communication with the gateway; and take a security action based upon the determination that the indication is indicative of the attempt to gain unauthorized access. | 04-17-2014 |
20140104738 | COORDINATED HIGH-IMPEDANCE FAULT DETECTION SYSTEMS AND METHODS - Systems and methods are presented for detecting high-impedance faults (HIFs) in an electric power delivery system using a plurality of coordinated high-impedance fault detection systems. In certain embodiments, a method for HIFs may include receiving first and second current representations associated with first and second locations of the electric power delivery system respectively. Based on at least one of the first and second current representations, the occurrence of an HIF may be determined. A relative location of the HIF may be determined based on a relative amount of interharmonic content associated with an HIF included in the first and second current representations, and a protective action may be taken based on the determined relative location. | 04-17-2014 |
20140100702 | DISTRIBUTED COORDINATED WIDE-AREA CONTROL FOR ELECTRIC POWER DELIVERY SYSTEMS - Distributed controllers in an electric power delivery system obtain measurements and equipment status, calculate derived values, and determine IED state, and share such with other distributed controllers and coordination controllers. Distributed controllers and coordination controllers further refine measurements, equipment status, derived values, and IED state. Control of the electric power delivery system is coordinated among the distributed controllers and the coordination controllers. | 04-10-2014 |
20140074414 | Fault Location Using Traveling Waves - Disclosed herein are various embodiments of systems and methods for calculating a fault location in electric power delivery system based on a traveling wave created by an electrical fault in the electric power delivery system. According to one embodiment, an intelligent electronic device may be configured to detect a transient traveling wave caused by an electrical fault. A first traveling wave value of the transient traveling wave may be determined and a corresponding first time associated with the first traveling wave may be determined. The IED may receive a second time associated with a second traveling wave value of the transient traveling wave detected by a remote IED. The distance to the remote IED may be known. An estimated fault location may be generated based on the time difference between the first time and the second time. Additional methods of calculating the fault location may also be employed. | 03-13-2014 |
20140068711 | Network Access Management via a Secondary Communication Channel - The present disclosure provides for selectively enabling a primary communication channel upon receipt of enablement instructions received via a secondary communication channel. In some embodiments, a first intelligent electronic device (IED) may be connected to a second IED via a primary communication channel. In various embodiments, the primary communication channel may be selectively and/or temporarily enabled by transmitting an enablement instruction via a secondary communication channel. The secondary communication channel may be relatively more secure than the primary communication channel. In some embodiments, the secondary communication channel may also connect the first and second IEDs. Accordingly, the first IED may transmit an enablement instruction to the second IED in order to temporarily enable communication via the primary communication channel between the first and second IEDs. | 03-06-2014 |
20140064162 | POWER MANAGEMENT IN A NETWORK OF STATIONARY BATTERY POWERED CONTROL, AUTOMATION, MONITORING AND PROTECTION DEVICES - A faulted circuit indicator periodically joins a network to report information and receive commands. The faulted circuit indicator optimizes the transmit power used to join the network so that an acceptable network acquisition time and/or robust routing through multiple nodes are obtained. | 03-06-2014 |
20140063661 | MOTOR RELAY WITH INTEGRATED ARC-FLASH DETECTION - Disclosed herein are various embodiments of devices and related methods for detecting an electrical arc event using a motor management relay and for suppressing the electrical arc event. The motor management relay may incorporate an optical arc-flash sensor configured to detect an optical event. Control logic may analyze the optical event and determine whether the optical event corresponds to an electrical arc event. When an electrical arc event is detected an instruction may be issued via a control port in communication with the control logic to implement a protective action. According to various embodiments, a plurality of sensors for monitoring electrical characteristics of a motor may also be in communication with the control logic. Input from the sensors may be analyzed in order to determine whether the optical event corresponds to an electrical arc event. | 03-06-2014 |
20130346419 | Electric Power System Waveform Search - The present disclosure relates to searching electric power system waveforms. Disclosed herein are various systems and methods for improving search performance through indexing electric power system waveforms using waveform attributes such as frequency, amplitude, angle, rate of change, and the like. According to some embodiments, multiple indexes may be used together to find information of interest. A reference signal may be utilized according to some embodiments. Normalizing a plurality of waveforms using a reference signal may facilitate the use of an index for comparing two arbitrary waveforms. This disclosure also relates to detecting and indexing islanding conditions in an electric power system. Various embodiments may utilize information relating to islanding conditions in connection with search operations. | 12-26-2013 |
20130322500 | Thermal Management of a Communication Transceiver in an Electrical Communication Device - Disclosed herein are various systems and methods relating to communication devices that include modular transceivers, such as small form pluggable transceivers. According to one embodiment, a communication device may include a chassis defining an interior and an exterior of the communication device. The chassis includes a top, a bottom, and a plurality of sides that together with the top and the bottom form an enclosure. One of the sides may include a first segment disposed in a first plane and a second segment disposed in a second plane. The second segment includes an outwardly extending communication transceiver housing configured to receive a communication transceiver. The communication transceiver may extend through an aperture in the second segment and into interior of the communication device to contact an electrical connector, while a second portion of the communication transceiver in the communication transceiver housing remains on the exterior of the communication device. | 12-05-2013 |
20130135780 | Protective Device with Metering and Oscillography - A device, such as an intelligent electronic device (IED), provides a monitoring and protective function for a power system. The protective function uses stimulus acquired from the power system to detect power system conditions and to take one or more protective actions responsive thereto. The device may detect arc flash events in the power system based upon electro-optical and/or current stimulus measurements obtained therefrom. The stimulus measurements may be recorded to use in metering, validation, identifying detector misoperation, and/or event oscillography. | 05-30-2013 |
20130096854 | Fault Location Using Traveling Waves - Disclosed herein are various embodiments of systems and methods for calculating a fault location in electric power delivery system based on a traveling wave created by an electrical fault in the electric power delivery system. According to one embodiment, an intelligent electronic device may be configured to detect a transient traveling wave caused by an electrical fault. A first traveling wave value of the transient traveling wave may be determined and a corresponding first time associated with the first traveling wave may be determined. The IED may receive a second time associated with a second traveling wave value of the transient traveling wave detected by a remote IED. The distance to the remote IED may be known. An estimated fault location may be generated based on the time difference between the first time and the second time. Additional methods of calculating the fault location may also be employed. | 04-18-2013 |
20130088799 | Asset Condition Monitoring in an Electric Motor - The motor monitoring system of the present disclosure uses several calculated monitoring values to determine a status of a motor and take a predetermined action when a threshold corresponding with the monitoring value is exceeded. The threshold may be calculated by an intelligent electronic device (IED) monitoring the motor. The predetermined action may include further monitoring of the motor. The predetermined action may include monitoring equipment not directly monitored by the IED. | 04-11-2013 |
20130018521 | Systems and Methods for Blackout Protection - A system for managing an electric power delivery system is disclosed that includes a set of remote intelligent electronic devices (IEDs) and a central IED. The remote IEDs may be configured to obtain information related to rotor angles, operating frequencies, rate of change of frequency, rotating inertia, and power consumption levels of loads and generators included in the electric power delivery system. The central IED may communicate with the remote IEDs to determine which loads and generators are associated with a sub-grid of the electric power delivery system and whether to disconnected certain loads or generators. Based on this determination, the central IED may direct the remote IEDs to disconnect loads or generators from the electric power delivery system, or to rapidly increase or decrease generator output as appropriate. | 01-17-2013 |
20120323397 | Electric Power System Automation Using Time Coordinated Instructions - A system for controlling and automating an electric power delivery system by executing time coordinated instruction sets to achieve a desired result. A communication master may implement the execution of time coordinated instruction sets in a variety of circumstances. The communication may be embodied as an automation controller in communication with intelligent electronic devices (IEDs). The communication master may also be embodied as an IED that is configured to coordinate the actions of other IEDs. The time coordinated instruction sets may include steps for checking status of power system equipment before executing. The time coordinated instruction sets may include reactionary steps to execute if one of the steps fails. The time coordinated instruction sets may also be implemented based on a condition detected in the electric power delivery system, or may be implemented through high level systems, such as a SCADA system or a wide area control and situational awareness system. | 12-20-2012 |
20120313490 | Power Angle Monitor - A system and method for monitoring the rotation of a generator rotor. The monitor uses a light beam directed toward the rotor to detect a marking thereon, and generates an electrical pulse when the marking is detected. The time between the pulse and a reference point (such as a zero crossing) of the signal waveform from the terminals of the generator may be used to calculate the power angle of the generator. The system is adaptive in that it can account for new markings on the rotor. The system may be connected to a network so that power angles from various generators on the electrical network may be compared. The system may further be connected to a common time source such that a time stamp may be applied to the power angles from various generators, allowing for more accurate comparison of the power angles. | 12-13-2012 |
20120312977 | Arc Flash Protection System with Self-Test - An method for automatically testing an arc flash detection system by periodically or continually transmitting electro-optical (EO) radiation through one or more transmission cables electro-optically coupled to respective EO radiation collectors. A test EO signal may pass through the EO radiation collector to be received by an EO sensor. An attenuation of the EO signal may be determined by comparing the intensity of the transmitted EO signal to an intensity of the received EO signal. A self-test failure may be detected if the attenuation exceeds a threshold. EO signals may be transmitted according to a particular pattern (e.g., a coded signal) to allow an arc flash detection system to distinguish the test EO radiation from EO radiation indicative of an arc flash event. | 12-13-2012 |
20120312971 | Electro-Optical Radiation Collector for Arc Flash Detection - An electro-optical (EO) radiation collector for collecting and/or transmitting EO radiation (which may include EO radiation in the visible wavelengths) for transmission to an EO sensor. The EO radiation collector may be used with an arc flash detection device or other protective system, such as an intelligent electronic device (IED). The arc flash detection device may detect an arc flash event based upon EO radiation collected by and/or transmitted from the EO radiation collector. The EO radiation collector may receive an EO conductor cable, an end of which may be configured to receive EO radiation. A portion of the EO radiation received by the EO radiation collector may be transmitted into the EO conductor cable and transmitted to the arc flash detection device. The EO radiation collector may be adapted to receive a second EO conductor cable, which may be used to provide redundant EO transmission and/or self-test capabilities. | 12-13-2012 |
20110260042 | Power Angle Monitor - A system and method for monitoring the rotation of a generator rotor and calculating a power angle using an optical rotor displacement monitor. The monitor uses a light beam directed toward the rotor to detect a marking thereon, and generates an electrical pulse when the marking is detected. The time between the pulse and a reference point (such as a zero crossing) of the signal waveform from the terminals of the generator is used to calculate the power angle of the generator. The system is adaptive in that it can account for new markings on the rotor. The system may be connected to a network so that power angles from various generators on the electrical network may be compared. The system may further be connected to a common time source such that a time stamp may be applied to the power angles from various generators, allowing for more accurate comparison of the power angles. | 10-27-2011 |
20090115564 | Systems and Methods for Forming an Isolated Transformer - A transformer to isolate a primary winding from a signal winding include a primary substrate (which may comprise a printed circuit board (PCB)) and a secondary substrate. The primary and secondary substrates may each have three openings to allow first and second E-E core halves to be joined therebetween. A first insulator may be disposed between the primary and secondary substrates to isolate the primary substrate from the secondary substrate. A second insulator may secure the primary and secondary substrates in place and insulate the secondary substrate from the core. The primary and secondary substrates may each include a Faraday shield its outer layers. A shield slit to prevent shorting between the legs of the E-E core may be formed by cutting a channel in the shield between the opening of the primary and secondary substrates. A retaining clip may be used to clamp together the primary substrate, first and second core E-E core halves, secondary substrate and second insulator. A primary winding and sense winding may be disposed within the primary substrate and a signal winding may be disposed within the secondary substrate. The primary, sense, and signal windings may be positioned so that the magnetic flux produced by the primary winding passes through the signal and sense windings in substantially equal proportions. The primary and signal winding may enter the E-E core from opposite directions to choke any common mode current therebetween. | 05-07-2009 |
20090115509 | Systems and Methods for Isolating an Analog Signal - An accurate linear equivalent of an analog signal may be produced across an isolation barrier by driving a primary transformer winding with a drive amplifier and compensation amplifier, where the compensation operational amplifier amplifies a difference between a signal produced on a sense winding of the transformer and a combination of the input analog signal and output of the drive amplifier. The system may be stabilized by a lead-lag network between the sense winding, input signal, and operational amplifier. The transformer may comprise an isolation barrier to isolate the input analog signal from a signal winding. The primary winding of the transformer, driven by the operational amplifier and driver amplifier circuit, may produce a linear equivalent of the input analog signal across the isolation barrier on a signal winding of the transformer. The transformer may comprise power supply windings connected to a power supply bridge rectifier and regulator circuit to control and supply power to the circuit components across the isolation barrier. The operational amplifier and drive amplifier circuit may be active for only a portion of each analog signal sampling period. The control signals may provide power during the rest of the sampling cycle. | 05-07-2009 |