Abstract: The present disclosure relates to systems and methods to detect a fault in an electric power system. One embodiment may detect a single phase broken conductor in a multi-phase electric power system. An intelligent electronic device (IED) may receive a plurality of measurements over time of a current through an electrical conductor in the electric power system. Based on the measurements of the current, a fault detection subsystem may determine a zero-sequence current, a negative-sequence current, and a positive-sequence current. The fault detection subsystem may determine a ratio of the zero-sequence current, the negative-sequence current, and the positive-sequence current, and may monitor the ratio over time. The fault detection subsystem may identify the broken conductor condition based on the ratio and a fault detection region. A protective action subsystem may implement a protective action based on identification of the broken conductor condition.

Abstract: The presently described systems and methods include differential protection architectures for power lines, including three-phase transmission lines and distribution lines, in which each protective device monitors and protects more than one power line. A protective device with multi-channel line current differential protection provides additional security from data corruption and/or single event upsets. A protective device on one end of a transmission line may include multiple communication channels to simultaneously receive independent differential data (e.g., current measurements) from protective devices on the other end of the transmission line. The device may use the independent channels of line current differential protection data to implement multiple independent differential protection functions for two or more power line segments.

Abstract: Disclosed herein are systems, devices, and methods for improving cybersecurity in electric power systems. In one embodiment, a local controller configured for use in an electric power system may include a measurement subsystem to receive a plurality of conditions related to electrical conditions in a microgrid. A communication subsystem may communicate a set of data related to conditions in the microgrid to a remote controller; and receive a plurality of requests for control actions from the remote controller. An analysis subsystem may generate an assessment of the plurality of requests for control actions in relation to the plurality of conditions related to electrical conditions in the microgrid and identify a subset of the plurality of requests for control actions from the remote controller for execution based on the assessment. A control action subsystem may then issue a control action to an asset in the microgrid.

Abstract: The present application relates to generating adaptive protective relay event reports. In one embodiment, a system comprises a power system response subsystem to monitor electrical parameters in an electric power system and to receive a trigger signal from a trigger source based on identification of an event in an electric power system. An adaptive event report subsystem is configured to generate an adaptive report depending on the trigger related to the event and based on a pre-trigger start, a duration, and a sampling rate. The adaptive event report comprises at least one electrical parameter related to the event beginning at a time established by the pre-trigger start, covering an interval established by the duration, and recorded at the sampling rate.

Abstract: An electric power system may include numerous devices electrically connected to numerous other devices. In some cases, it may be beneficial to quickly determine and resolve an electric power system topology. Using a protection and control (PAC) algorithm, an electric power delivery system may be identified and represented as a graph including nodes and edges. The nodes represent electric power sources, busses, and ground. The edges represent circuit breakers, disconnects switches, and ground switches. By representing the electric power delivery system as a graph, the connections between various nodes (e.g., power sources, busses, grounds) and edges (e.g., circuit breakers, disconnects, ground switches) may be quickly and easily realized, represented, and visualized. Doing so may reduce programming and testing time after a change to the topology.

Abstract: Techniques and apparatus presented herein are directed to improvements in maintaining voltage and frequency stability of an electric power delivery system. To do so, model predictive control (MPC) may be used. Input data may be obtained for a sampling period and may include a current system state. The MPC may predict an initial trajectory of the input data, output data, and a state of the system for a prediction period. The MPC may linearize the output and state trajectories and determine an updated input trajectory based at least in part on the linearized output trajectory. The MPC may determine control inputs to the system which achieve the updated input trajectory for a control period. The MPC may transmit control signals based at least in part on the control inputs to equipment associated with the input data.

Abstract: The present disclosure pertains to devices, systems, and methods for monitoring a generator. In one embodiment, the system may include a measurement subsystem to receive a plurality of split-phase measurements of branch currents associated with the at least one generator. A split-phase transverse differential monitoring subsystem may receive the plurality of split-phase measurements of branch currents associated with the at least one generator and may generate an offset value representing a standing split-phase current. A protective action subsystem may generate a first protective action based on the phasor operating current.

Abstract: Signal transducers in electrical communication with shorted leads of current transformers are used to provide monitoring and protection functions to an electric power delivery system. Differential protection is performed by comparing a predetermined threshold against a voltage signal from series-connected leads of signal transducers in electrical communication with shorted leads of current transformers. The signal transducers may be Rogowski coils. Signal transducers in communication with shorted leads may be used to improve safety and increase performance of the current transformers by decreasing susceptibility to saturation.

Abstract: A table assembly is used to support a workpiece to facilitate bending of the workpiece. The table assembly is attached to a press brake system and include a base and a clamp. The clamp is movable relative to the base to enable placement of the workpiece onto the base, and the clamp secures the workpiece to the base to block relative movement between the workpiece and the press brake system without additional user operations. The workpiece is secured via the table assembly without a manual force (e.g., to hold the workpiece in place) while the press brake system operates to bend the workpiece. The table assembly reduces, limits, or eliminates certain user operations during metalworking. The table assembly improves user experience (e.g., reduce an amount of manual labor) and/or efficiency associated with press brake operations.

Abstract: A shunt resistor may, in some cases, receive interference from magnetic fields. The shunt resistor may include a resistive element coupled between multiple conductive elements, and measurement circuitry coupled to the leads, forming an electrically conductive loop. Current through the shunt resistor may be determined by measuring the current through the resistive element at the leads. An induced voltage in the loop may be determined by the product of the loop area and the magnetic field passing through the loop. Consequently, when a magnetic field is passed through the shunt resistor loop, an undesirable interfering signal may be produced, distorting the output signal of the shunt resistor. As the interfering signal is a product of the loop area and the magnetic field, the geometry of the shunt resistor may be modified to reduce the loop area and thus reduce or minimize the interference on the shunt resistor.

Abstract: This disclosure pertains to systems and methods to detect network errors in a parallel redundant protocol (PRP) network. A node-level redundancy error subsystem of an intelligent electronic device (IED) maintains records (e.g., counts) of information associated with missing duplicate frames expected from node devices on the PRP network via redundant first and second local area networks (LANs). Non-zero counts of missing duplicate frames may be identified as network errors.

Abstract: An electric power system may include numerous devices electrically connected to numerous other devices. In some cases, it may be beneficial to quickly determine and resolve an electric power system topology. The present disclosure is directed to systems and methods for resolving an electric power system topology using bit pattern sequence compression. A multi-node device may be electrically coupled to one node per side. Each node may be associated with a bit value. The bit values may be compared to determine if the nodes are electrically coupled. This process may be recursively performed for all of the multi-node devices, until it is determined which devices are electrically coupled and which are electrically isolated.

Abstract: Various examples of systems and methods are described herein in which multiple intelligent electronic devices (IEDs) are connected in a network. A software-defined network (SDN) controller may include a rule subsystem, a test mode subsystem, a packet inspection subsystem, and a validation subsystem. The rule subsystem may define a plurality of flow rules. A test mode subsystem may operate the SDN in a testing mode. A packet insertion subsystem may insert test packets within the SDN while the SDN is in the testing mode. The validation subsystem may validate or fail each flow rule depending on how the various test packets are handled.

Abstract: Circuit breakers may perform a variety of operations, including isolating a faulty part of the power system that may result in a cascading outage. However, circuit breaker operations may cause wear and tear of the tripping assembly components, which eventually cause the circuit breaker to wear out. Additionally, long periods of non-operations may cause the mechanical parts inside a circuit breaker to move sluggishly or, in some instances, fail to move at all. In an embodiment, a system includes a circuit breaker that trips to control power flow and an intelligent electronic device (IED) including an electronic display. The IED receives measurement data associated with a trip event for the circuit breaker, generates a current profile based on the measurement data, and presents the current profile via the electronic display.

Abstract: A wireless radio repeater includes an antenna configured to receive a message associated with an electric power delivery system. The wireless radio repeater also includes circuitry configured to receive electrical measurement data, identify a condition of the electric power delivery system based on the electrical measurement data, and cause the antenna to re-transmit the message received via the antenna in response to identifying the condition based on the electrical measurement data.

Abstract: The present application discloses systems and methods related to protection of a reactor in an alternating current (AC) electric power system. In one embodiment, a system may include a protective action subsystem to implement a protective action based on identification of a fault condition associated with a reactor. A frequency determination subsystem may determine when a frequency of the AC voltage is outside of a range defined by a lower threshold and an upper threshold and may identify a change in the frequency associated with de-energization of a line in electrical communication with the reactor. A supervisory subsystem may restrain implementation of the protective action when the frequency is outside of the range or when the change in the frequency is associated with de-energization of the line in electrical communication with the reactor.

Abstract: A system for voltage signal distribution in a digital substation protection system. In a system where a voltage signal from a bus is not available, an alternative voltage secondary signal may be selected as a reference voltage and made available to the appropriate protection devices in a digital substation protection system for synchronism check. Voltage signals may be distributed using software-defined networking. A voltage selection controller may select the reference voltage and control distribution of the voltage signal using the software-defined networking communication system.

Abstract: This disclosure pertains to identifying and configuring an in-band controller operating on a host in a software defined network (SDN), the host configured to use a parallel redundancy protocol (PRP). In one embodiment, a system may include a network in communication with the host, the network comprising a plurality of switches interconnected with a plurality of physical links. The in-band controller is in communication with the network and includes a PRP identification subsystem to generate a packet configured such that the network forwards the packet back to the in-band controller, to analyze the packet and determine that the packet conforms to PRP, and to identify a first communication host in communication with the network and configured to operate using PRP. A traffic routing subsystem of the in-band controller may create a plurality of PRP communication flows between the in-band controller and the first communication host.

Abstract: Disclosed herein are systems for determining a broken conductor condition in a multiple-phase electric power delivery system. It has been observed that broken conductors pose a safety concern when occurring in the presence of people or vulnerable environmental conditions. Broken conductor conditions disclosed herein may be used to detect and trip the phase with the broken conductor, thus reducing or even eliminating the safety risk. Broken conductors may be determined using detected phase series arcing differences in one phase without commensurate differences in other phases. In various embodiments the phase series arcing attributes may be phase current monitored for decrement and/or phase resistance monitored for increase.