GE MiCOM P747 Agile, Техническое руководство

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The IEC 61850 compatible interface standard provides capability for the following:
● Read access to measurements
● Refresh of all measurements at the rate of once per second.
● Generation of non-buffered reports on change of status or measurement
● SNTP time synchronization over an Ethernet link. (This is used to synchronize the IED's internal real
time clock.
● GOOSE peer-to-peer communication
● Disturbance record extraction by file transfer. The record is extracted as an ASCII format COMTRADE
file
● Controls (Direct and Select Before Operate)
Note:
Setting changes are not supported in the current IEC 61850 implementation. Currently these setting changes are
carried out using MiCOM S1 Agile.
10.5 IEC 61850 DATA MODEL IMPLEMENTATION
The data model naming adopted in the IEDs has been standardised for consistency. Therefore the Logical
Nodes are allocated to one of the five Logical Devices, as appropriate.
The data model is described in the Model Implementation Conformance Statement (MICS) document, which
is available as a separate document.
10.6 IEC 61850 COMMUNICATION SERVICES IMPLEMENTATION
The IEC 61850 communication services which are implemented in the IEDs are described in the Protocol
Implementation Conformance Statement (PICS) document, which is available as a separate document.
10.7 IEC 61850 PEER-TO-PEER (GSSE) COMMUNICATIONS
The implementation of IEC 61850 Generic Object Oriented Substation Event (GOOSE) enables faster
communication between IEDs offering the possibility for a fast and reliable system-wide distribution of input
and output data values. The GOOSE model uses multicast services to deliver event information. Multicast
messaging means that messages are sent to all the devices on the network, but only those devices that
have been appropriately configured will receive the frames. In addition, the receiving devices can specifically
accept frames from certain devices and discard frames from the other devices. It is also known as a
publisher-subscriber system. When a device detects a change in one of its monitored status points it
publishes a new message. Any device that is interested in the information subscribes to the data it contains.
Note:
Multicast messages cannot be routed across networks without special equipment.
Each new message is re-transmitted at configurable intervals, to counter for possible corruption due to
interference, and collisions, therefore ensuring delivery. In practice, the parameters controlling the message
transmission cannot be calculated. Time must be allocated to the testing of GOOSE schemes before or
during commissioning, in just the same way a hardwired scheme must be tested.
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