Woodward highprotec MRI4, User Manual

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Communication Protocols
IEC61850
IEC61850
Introduction
To understand the functioning and mode of operation of a substation in an IEC61850 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 IEDs (Intelligent Electronic Devices) communicate in vertically direction
with the higher level control center via SCADA. The horizontal communication is exclusively realized by wiring
output relays (OR) and digital inputs (DI) among each other.
In an IEC61850 environment communication between the IEDs takes place digitally (via Ethernet) by a service
called GOOSE (Generic Object Oriented Substation Event). 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 IEC61850 capable device includes a description of it's own functionality and communications skills (IED
Capability Description, *.ICD).
By means of a Substation Configuration Tool to describe the structure of the substation, assignment of the devices
to the primary technique, etc. a virtual wiring of the IEDs among each other and with other switch gear of the
substation can be done. A description of the substation configuration will be generated in form of a *.SCD file. At
last this file has to be submitted to each device. Now the IEDs are able to communicate closed among each other,
react to interlockings and operate switch gear.
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 IEC61850
environment:
1. Parameter setting of the IEDs
Ethernet installation
TCP/IP settings for the IEDs
2. IEC61850 configuration (software wiring)
a) Exporting an ICD file from each device
b) Configuration of the substation
(generating a SCD file)
c) Transmit SCD file to each device
233 MRI4 DOK-HB-MRI4-2E
IED1 IED2 IED3
IEC61850
Master
Ethernet
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ad
a
IE
C
61
85
0
GOOSE IEC61850 soft wiring
IED1 IED2 IED3
Modbus-TCP
Master
Ethernet
Sc
ad
a
M
od
bu
sT
C
P
Conventional hard wiring
DI BO DI BO DI BO