3.5 IEC 61850
Introduction
To understand the functioning and mode of operation of a substation in an IEC 61850
automation environment, it is useful to compare the commissioning steps with those of a
conventional substation in a Modbus TCP environment. In a conventional substation, the
individual Intelligent Electronic Devices (IEDs) communicate in a vertical direction with
the higher level control center via Communication. The horizontal communication is
exclusively realized by wiring relay outputs (RO) and digital inputs (DI) together.
In an IEC 61850 environment, communication between the IEDs takes place digitally (via
Ethernet) by a service called Generic Object Oriented Substation Event (GOOSE). By
means of this service, information about events is submitted between each IED. Therefore
each IED has to know about the functional capability of all other connected IEDs.
Each IEC 61850 capable device includes a description of its own functionality and
communications skills (IED Capability Description, *.ICD). By means of a Substation
Conguration Tool to describe the structure of the substation, assignment of the devices
to the primary technique, etc., virtual wiring of the IEDs between each other and with
other switch gear of the substation can be achieved. A description of the substation
conguration will be generated in the form of an *.SCD le. Finally, this le has to be
submitted to each device. Now the IEDs are able to communicate with each other, react
to interlockings, and operate switch gear.
IED1 IED2 IED3
Master
Ethernet
IEC 61850
GOOSE IEC61850 soft wiring
IED1 IED2 IED3
Master
Ethernet
ModbusTCP
Conventional hard wiring
DI RO DI RO DI RO
IEC 61850Modbus-TCP
SCADA
SCADA
E_F62
Commissioning steps for a conventional substation with modbus TCP environment:
• Parameter setting of the IEDs
• Ethernet installation
• TCP/IP settings for the IEDs
•
Wiring according to wiring scheme
Commissioning steps for a substation with IEC 61850 environment:
• Parameter setting of the IEDs
• Ethernet installation
118 www.eaton.com EMR-3MP0
3 Communication Protocols
3.5 IEC 61850