A hierarchical power flow control system includes power flow control devices, a communication coordinator and a gateway. The gateway provides diagnostics, prognostics, and health monitoring, and communicates with an external energy management system (EMS). Operation and actions are based on self-health monitoring, self-prognostics, and analysis and prediction processing in the gateway, in communication with the external energy management system.

A microgrid is re-synchronized to a main grid or substation by determining a degree of bus angle or frequency mismatch and bus voltage mismatch between the microgrid and the main grid or substation prior to re-synchronization, determining an amount of power adjustment needed to reduce the bus angle or frequency mismatch and bus voltage mismatch to below respective predetermined thresholds, determining at least one participation factor for each microgrid bus, each participation factor indicating an amount of influence power injection by the corresponding bus has on the bus angle or frequency mismatch or on the voltage mismatch, allocating the amount of power adjustment to the microgrid buses in proportion to the participation factors assigned to the buses, and re-synchronizing the microgrid to the main grid or substation responsive to the bus angle or frequency mismatch and bus voltage mismatch satisfying the respective predetermined thresholds.

A power transmission system includes a plurality of electrical substations and a plurality of transmission lines arranged to connect the plurality of electrical substations to form a power transmission network; and a controller system arranged to control a power transmission within the power transmission network. The controller system includes: a detection module arranged to detect an occurrence of a fault in at least one faulty electrical substation of the plurality of electrical substations; and a restoration module arranged to at least temporally maintain an output power of the at least one faulty electrical substation; and wherein at least one of the plurality of electrical substations is operable to facilitate maintaining of the output of the at least one faulty electrical substation upon the detection of the occurrence of the fault.

Techniques are described for disaggregation of renewable energy generation on an electricity distribution system. Aggregate power measurements are identified a distribution substation. Active power load of the distribution substation and active power generated by renewable energy sites can be disaggregated from the aggregate power measurements.

A system for autonomous control in power systems is disclosed. In particular, a secure overlay communication model (“SOCOM”) is disclosed, the system including a combination of hardware and software for detecting power grid states, and determining appropriate actions for addressing detected states. The SOCOM is a logic-based system deployed onto computing devices such as field programmable gate arrays installed at bus controllers, Supervisory Control and Data Acquisition Systems (“SCADAs”), Intelligent Electronic Devices (“IEDs”), or other computing devices in power grid stations and substations. The logic-based nature of the SOCOM allows for seamless integration with preexisting power system equipment. In response to detecting various power grid faults such as line failures and over-current states, the system automatically rearranges power line configurations at the power stations and/or substations. The SOCOM further provides improvements relating to optimal power flow, cost-based power distribution, load management, voltage/volt-amp reactance (“VAR”) optimization, and self-healing.

The disclosure provides a method for fast reconfiguration of power supply grid in tens of milliseconds after power grid failure. The master station of fast reconfiguration of power grid concentrates the network status information from the client stations at transformer substations or power plants, and compares it with the built-in control strategy table which deals with possible faults. When an expected power gird disconnection fault is detected, the pre-start switch-on instruction is sent to the client stations with multiple breakers which can reconnect the grid. When the fault is cleared, the client stations shall identify the fault clearing time according to the local information, and send the instruction of synchronous switch-on to the corresponding local breakers which can reconnect the separated grids. At the same time, the master station independently monitors the removal of the fault, and sends the backup switch-on signal with synchronism check to the corresponding breakers which can reconnect the separated grids. Based on the above mechanism, the disconnected grid can be reconnected within 150 ms after disconnecting. After the interconnection of the grid is restored, the breakers that form the electromagnetic ring network switch off.

Systems and methods to send or receive redundant Generic Object Oriented Substation Event (GOOSE) messages are described. An intelligent electronic device may obtain power system data from a power system. The TED may publish the power system data in a first GOOSE message and publish the same power system data in a second GOOSE message. The second GOOSE message may have different header information than the first GOOSE message to allow the subscriber to determine that the redundant GOOSE messages are both received. If the first and second GOOSE message are duplicates with identical header information but unique trailer information methods allow the subscriber to determine that the duplicate GOOSE messages are both received.

We provide a method of detecting a power island in a power distribution network of the type comprising: a plurality of distribution lines connecting consumers to electrical power supplied from one or more substations, a plurality of circuit breakers and/or switches each operable to connect and disconnect transmission of electrical power along an associated distribution line, each being associated with a communication device operable to communicate the status of the circuit breaker and/or switch to a monitoring system, and one or more embedded generators each connected to a distribution line within the power distribution network so as to provide electrical power to the power distribution network, the method including the steps of: storing at the monitoring system data representing the connectivity of the distribution network including a status of each circuit breaker and/or switch, receiving at the monitoring system a communication from a communication device that an associated circuit breaker and/or switch is disconnected, determining at the monitoring system, using the data representing the connectivity of the distribution network, whether the disconnection of the circuit breaker and/or switch has resulted in a portion of the power distribution network being electrically disconnected from the remainder of the power distribution network that remains electrically connected to the one or more substations, and identifying the disconnected portion of the power distribution network as a power island within the power distribution network.

A system and a method for locally controlling delivery of electrical power along the distribution feeder by measuring certain electricity parameters of a distribution feeder line using a substation phasor measurement unit (PMU) electrically coupled to a substation distribution bus at a first node on the feeder line, and at least one customer site PMU electrically coupled to a low voltage end of a transformer at a customer site, wherein the transformer is coupled by a drop line to a second node on the distribution feeder line and the customer site is coupled by another drop line to the transformer, and by controlling at least one controllable reactive power resource and optionally a real power resource connected to the second node or at the customer site. Related apparatus, systems, articles, and techniques are also described.

Systems and methods to send or receive redundant Generic Object Oriented Substation Event (GOOSE) messages are described. An intelligent electronic device may obtain power system data from a power system. The IED may publish the power system data in a first GOOSE message and publish the same power system data in a second GOOSE message. The second GOOSE message may have different header information than the first GOOSE message to allow the subscriber to determine that the redundant GOOSE messages are both received. If the first and second GOOSE message are duplicates with identical header information but unique trailer information methods allow the subscriber to determine that the duplicate GOOSE messages are both received.