A device, a method and a system for monitoring an electrical connection status of a disconnector device (110). The disconnector device (110) being connectable to pole-mounted equipment in a power distribution or transmission grid (200), thereby disconnecting the pole-mounted equipment. The connection status monitoring device (100) comprises a determining section (130) configured to determine whether the disconnector device (110) has been activated and to generate connection status indicator data, indicative of whether the disconnector device (100, 110) has been activated. The determining section (130) further comprises a wireless communication section (140) which is adapted to connect to a wireless communication infrastructure (150) using a wireless communication protocol, and to transmit the connection status indicator data over the wireless communication infrastructure (150).

A smart, self-feeding fuse with current detection and communication capabilities for use in overhead medium voltage electrical distribution networks (15 kV to 34 kV). The device is configured to detect transient or permanent electric faults (sensor), and/or to be used as a communication device (gateway) that preserves the main protection function of the fuse element. The device is assembled on a base fuse and is simply installed by using a maneuver pole, similarly to the installation of a conventional fuse tube. The invention is self-fed by a high output current transformer with the help of photovoltaic cells, using a supercapacitor bank as the only power storage element.

There is provided mechanisms for handling time shifted data streams in a substation network. A method is performed by an IED. The method comprises receiving a respective data stream from at least two time synchronized data sources in the substation network. The method comprises blocking, upon detecting a time shift between the data streams resulting from one of the data sources losing its time synchronization and until a configured time amount has expired, a protection function in the substation network from acting based on the data streams.

A system and method for fault location and isolation in an electrical power distribution network, where the network includes a plurality of switching devices provided along a feeder. The method includes detecting an overcurrent event in the network from the fault and interrupting the overcurrent event by opening and then immediately locking out or subsequently reclosing and testing the fault. A count value is increased in each switching device that detected the overcurrent event. A count and current (C&I) message is sent from each of the switching devices that detected the overcurrent event and then detected the loss of voltage upstream to an upstream neighbor switching device. Current measurements in the C&I messages, measured current by the devices and the counts values in the devices determine what devices are opened to isolate the fault.

A current differential relay apparatus includes a first relay and a second relay. The first relay calculates a first differential current and a first suppression current, using a first current and a second current, and performs a ratio differential relay operation based on the first differential current and the first suppression current. The second relay calculates a maximum of results of add operations of the first current and the second current as a second differential current, calculates an add operation of the maximum of the first current and a maximum of the second current as a second suppression current, and performs a ratio differential relay operation based on the second differential current and the second suppression current. The current differential relay apparatus includes an output controller that outputs an operation signal based on results of operations performed by the first and second relays.

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.

A power system includes multiple power units (PUs), each including a circuit breaker (CB), a local controller (LC) and an intelligent electronic device (IED). For any one of the PUs, the IED, when determining that the CB has mechanically failed, outputs a disconnect message via a network to the IED(s) of the remaining PU(s). For each of the remaining PU(s), based on the disconnect message, the IED thereof, when determining that the corresponding CB is a relevant CB, outputs a trip control signal that indicates to trip for receipt by the corresponding LC, so that the LC causes the CB to switch to an open state.

The invention is related to a monitoring and protection device of power distribution transformers on the low voltage side. Said device monitors in a permanent manner the functioning of the transformer and provides a record of all the information in case of a fault. Additionally, the invention device provides the protection of the transformer in case of a fault, allowing a partial impact on the service and preventing peak currents that may reduce the useful life of the transformer. The device has a remote communication module that allows the transmission of the recorded data, a control module that may be activated remotely and a visual alert module that reduces the risk in the handling of the device.

The present invention concerns a node of an HVDC grid composed of HVDC nodes and of a plurality of links interconnecting the HVDC nodes, each HVDC node being interconnected to at least one HVDC node of the HVDC grid by a link composed of conductive cables for high voltage direct current transportation and one optical fiber, at least one HVDC node being interconnected to at least two HVDC nodes, each HVDC node comprising, for each link connecting the HVDC node to the at least one other HVDC node, a link module comprising a fault sensing device, a breaker, and an optical transceiver for communicating through the optical fiber of the link.

A fault detection system that that prevents a recloser from reclosing if a fault is determined to be internal to a transformer, where the recloser is configured to perform a reclosing operation in response to detecting overcurrent. The recloser includes a sensor, such as a light sensor, directed towards the transformer and detecting a fault event. If the recloser detects overcurrent, but the sensor does not detect the fault event, it is assumed that the fault is internal to the transformer and the recloser is prevented from reclosing.