Voltage selection control scheme for synchronism check in digital substations
View Patent ↗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.
1 . A system for use in an electric power system, the system comprising:
a communication interface configured to receive a plurality of data streams over time and comprising:
a first data stream comprising a plurality of voltage measurements associated with a plurality of locations within an electric power system;
a second data stream comprising a plurality of status indicators associated with a plurality of devices configured to selectively connect and disconnect portions of the electric power system;
a topology subsystem configured to determine a topology of the electric power system based on the plurality of status indicators;
a dynamic reference voltage selection subsystem configured to identify:
a first subset of the plurality of voltage measurements associated with a first portion of the electric power system;
a second subset of the plurality of voltage measurements of a second portion of the electric power system, the first portion of the electric power system and the second portion of the electric power system being electrically disconnected; and
a protection device associated with the second portion of the electric power system; and
a routing subsystem configured to dynamically route the first subset of the plurality of voltage measurements to the protection device associated with the second portion of the electric power system.
2 . The system of claim 1 , wherein the first subset of the plurality of voltage measurements is configured to be used by the protection device as a reference voltage in connection with a synchronism check prior to connection of the first portion of the electric power system and the second portion of the electric power system.
3 . The system of claim 1 , wherein the routing subsystem is configured to coordinate a plurality of communication flows with a software-defined network controller.
4 . The system of claim 3 , wherein the software-defined network controller is configured to implement communication flows within a software-defined network data plane.
5 . The system of claim 1 , wherein the first data stream comprises a consolidated representation of data gathered from a plurality of merging units distributed throughout the electric power system.
6 . The system of claim 1 , wherein the protection device comprises a feeder protection relay.
7 . The system of claim 1 , wherein the protection device comprises a bus protection relay.
8 . A method for use in an electric power system, the method comprising:
receiving, using a communication interface, a plurality of data streams over time and comprising:
a first data stream comprising a plurality of voltage measurements associated with a plurality of locations within an electric power system;
a second data stream comprising a plurality of status indicators associated with a plurality of devices configured to selectively connect and disconnect portions of the electric power system;
determining, using a topology subsystem, a topology of the electric power system based on the plurality of status indicators;
identifying, using a dynamic reference voltage selection subsystem:
a first subset of the plurality of voltage measurements associated with a first portion of the electric power system;
a second subset of the plurality of voltage measurements of a second portion of the electric power system, the first portion of the electric power system and the second portion of the electric power system being electrically disconnected; and
a protection device associated with the second portion of the electric power system; and
dynamically routing, using a routing subsystem, the first subset of the plurality of voltage measurements to the protection device associated with the second portion of the electric power system.
9 . The method of claim 8 , further comprising wherein the first subset of the plurality of voltage measurements is configured to be used by the protection device as a reference voltage in connection with a synchronism check prior to connection of the first portion of the electric power system and the second portion of the electric power system.
10 . The method of claim 8 , wherein the routing subsystem is configured to coordinate a plurality of communication flows with a software-defined network controller.
11 . The method of claim 10 , wherein the software-defined network controller is configured to implement communication flows within a software-defined network data plane.
12 . The method of claim 8 , wherein the first data stream comprises a consolidated representation of data gathered from a plurality of merging units distributed throughout the electric power system.
13 . The method of claim 8 , wherein the protection device comprises a feeder protection relay.
14 . A system for substation protection in an electric power system, comprising:
a first bus;
a plurality of feeders in electrical communication with the first bus;
a plurality of voltage transformers in electrical communication with a respective feeder;
a plurality of merging units in electrical communication with a respective voltage transformer;
a protection device configured to receive signals from the plurality of merging units; and
a programmable communications network in communication with the plurality of merging units and the protection device, the programmable communications network comprising:
a communications network controller;
a logic controller configured to dynamically select a voltage signal from one of the plurality of merging units as a reference voltage; and
a plurality of programmable switches in communication with the communications network controller configured to provide a first dynamically selected reference voltage associated with the first bus to a first protection device.
15 . The system of claim 14 , comprising a topology subsystem;
wherein the plurality of merging units are further configured to provide a plurality of status indicators associated with a plurality of switching devices in the electric power system and the topology subsystem is configured to determine a topology of the electric power system based on the plurality of status indicators.
16 . The system of claim 15 , wherein the logic controller is configured to provide the first dynamically selected reference voltage based on the topology of the electric power system.
17 . The system of claim 16 , wherein the protection device comprises a feeder relay.
18 . The system of claim 14 , further comprising a second bus;
wherein the logic controller is further configured to provide a second dynamically selected reference voltage associated with the second bus to a second protection device.
19 . The system of claim 18 , wherein the second protection device comprises a bus protection relay.
20 . The system of claim 14 , wherein the programmable communications network comprises a software-defined network.