A system for controlling a power distribution network providing power using a plurality of phases comprises an electronic processor and memory storing instructions that, when executed by the electronic processor, cause the system to receive a loss of voltage fault indication associated with a fault in the power distribution network. The electronic processor identifies a first subset of the plurality of phases associated with the loss of voltage fault indication and a second subset of the plurality of phases not associated with the loss of voltage fault indication. The first and second subsets each include at least one member. The electronic processor identifies a downstream isolation device downstream of the fault. The electronic processor sends an open command to the downstream isolation device for each phase in the first subset. The electronic processor sends a close command to a tie-in isolation device downstream of the downstream isolation device.

A system for controlling a power distribution network providing power using a plurality of phases comprises an electronic processor and memory storing instructions that, when executed by the electronic processor, cause the system to receive a loss of voltage fault indication associated with a fault in the power distribution network. The electronic processor identifies a first subset of the plurality of phases associated with the loss of voltage fault indication and a second subset of the plurality of phases not associated with the loss of voltage fault indication. The first and second subsets each include at least one member. The electronic processor identifies a downstream isolation device downstream of the fault. The electronic processor sends an open command to the downstream isolation device for each phase in the first subset. The electronic processor sends a close command to a tie-in isolation device downstream of the downstream isolation device.

The wide application of power electronic components in power systems with renewable energy sources has changed the fault characteristics of conventional power systems, resulting in the performance degradation of conventional protections. To solve these problems, a novel principle of pilot protection based on structural similarity and square error criteria is provided. The structural similarity criterion utilizes the difference of fault characteristics between renewable sources and synchronous generators to identify internal faults, and the square error criterion is used to solve abnormal calculation of the conventional similarity based protection. Compared with conventional differential protections, the disclosed protection shows excellent performance in speed and reliability during various faults.

An electronic protection device for electric power distribution grids, the electronic protection device being adapted to control one or more switching devices in an electric power distribution grid and being capable of communicating, at local level, with one or more sensors or electronic devices of the electric power distribution grid and, at remote level, with a remote computerised platform. The electronic protection device is adapted to receive first grid monitoring data indicative of physical quantities related to the operation of the electric power distribution grid from the sensors or electronic devices, the first grid monitoring data including at least measured values indicative of a line current flowing along an electric line of the electric power distribution grid. The electronic protection device is adapted to carry out a predictive monitoring procedure of the operating conditions of the electric power distribution grid.

Systems and methods for facilitating selected communications among primary protection relays using a supervisory system with a configurable input/output (IO) map. Primary protection relays may obtain signals from equipment associated with an electric power delivery system and provide primary protection without need for communication. The primary protection relays may communicate a unique identifier as well as signal values, states, and commands to the supervisory system. The supervisory system may route specifically identified communications among primary protection relays in accordance with a configurable IO map by transmitting selected portions of the communications on a port associated with the receiving primary protection relay. The primary protection relays may perform secondary protection and other operations using the communicated information.

Systems and methods may be used to determine fault types and/or directions even during a loss of potential by receiving, at one or more processors, an indication of a pre-fault power flow direction for a power delivery system. The one or more processors then determine a fault direction during a fault for the power delivery system using current vector angles and the pre-fault power flow direction.

A control system and method for a group of interconnected feeders which enables fault location, isolation and service restoration without requiring each switch to have topology knowledge of devices in adjacent feeders. The method defines, for each switch, connectivity and X/Y directional information about its neighboring switches and propagates this information throughout each feeder. A leader device is also determined for each feeder. Information about topology of adjacent feeders is not needed by all devices. Only normally-open tie switches which define a boundary between two adjacent feeders have knowledge of the devices in both feeders. Switches which open during fault isolation automatically find open tie switches in a direction opposite the fault, and request service restoration downstream of the fault by providing power from an adjacent feeder. Leader devices ensure an overload condition is not created before initiating opening and closing operations of switches downstream of the fault.

Adaptive protection methods and systems for protecting agains) extreme fault currents in a power system are provided. Communication capabilities and protocols defined in IEC 61850 can be used to provide smart cascading switching actions for removing the fault from the power system. A supervisory protection algorithm can be used, and the protection can be activated if the fault current is higher than a breaking capacity of the circuit breakers of the power system.

Systems and methods to estimate trapped charge for a controlled automatic reclose are described herein. For example, an intelligent electronic device (IED) may calculate an analog amount of trapped charge of each phase of a power line based on voltage measurements of the power line. The IED may close a switching device of each phase at a time corresponding to a point-on-wave associated with the analog amount of trapped charge of the respective phase.

A system and method for feeder protection in an electrical power network nodal point including at least three feeders. In the system and the method it is executed in an intelligent electronic device reserved for the feeder, on the basis of the at least one measured electrical quantity actual in the respective feeder, at least one first protection function monitoring a power system related condition of the respective feeder, as well as in a central intelligent electronic device, for at least one feeder, at least one second protection function monitoring the same power system related condition of the feeder. Furthermore the central intelligent electronic device is configured to further execute for the at least one feeder, on the basis of the at least one measured electrical quantity actual in the other feeders connected to the same nodal point, at least one third protection function monitoring the same power system related condition of the feeder.