Inter-Substation Communication leveraging IEC 61850 for wide area substation communications
Dr. Alexander Apostolov
October 2016Amsterdam, The Netherlands
Questions
• What are we doing?
• Why are we doing it?
• How are we doing it?
What are we doing?
• Substation-to-substation communications for protection, automation and control
• Horizontal communications for applications such as accelerated transmission line protection schemes
• Vertical communications for applications such as System Integrity Protection Schemes
Ride-Through Capability
Page 4
Transmission Line Protection
Distance
Protection
A B
Distance
Protection
t
F1 F2 F3
Page: 6
Accelerated Scheme
IEC 61850 Based Accelerated Line Protection
A Distance
Protection 1
A B
B Distance
Protection 1
F1 F2 F3
Ethernet
Switch
Ethernet
Switch
A Distance
Protection 2B Distance
Protection 2
Page 8
SIPS Hierarchy
SIPS Functionality
•SIPS can be considered as systems that have three main types of functional elements:
–System monitoring elements
–Protection elements
–Execution elements
Why are we doing it?
• There are requirements for improving the quality, reliability and efficiency of PAC systems
• Quality: the standard of something as measured against other things of a similar kind.
• Reliability: the ability of an apparatus or system to consistently perform its intended function without degradation or failure.
• Efficiency: the extent to which a resource is used in order to effectively achieve an objective.
Why are we doing it?
• Conventional client-server protocols such as IEC60870-5-101, IEC60870-5-104 and DNP 3.0 as connection oriented and do not meet the performance requirements for many PAC applications
• They do not support high-speed peer-to-peer communications
• The detailed semantical object model in IEC 61850 is not available in other protocols
Why are we doing it?
• IEC 61850 is not just a communications protocol
• It supports a standardized engineering process based on the different System Configuration Language (SCL) files
• Substation-to-Substation communications engineering is based on System interface Exchange Description (SED) files
System interface Exchange Description (SED)
How are we doing it?
• Use of IEC 61850 GOOSE and sampled values based versus conventional hardwired interfaces
• Using GOOSE over existing communications channel
• Using GOOSE over Layer 2
• Using GOOSE over Layer 2.5
• Using R-GOOSE
IEC 61850 Services
Page 15
GSE Messages:
Page 16
Analog GOOSE Applications
IEC 61850 Reports
• IEC 61850-90-1 – Using IEC 61850 for communicationbetween substations
• IEC 61850-90-5 – Using IEC 61850 to transmitsynchrophasor information according to IEEE C37.118
Page 18
SS-SS Tunneling
SS-SS Mechanism
IEC 61850 Based Accelerated Line Protection
A Distance
Protection 1
A B
B Distance
Protection 1
F1 F2 F3
A Distance
Protection 2B Distance
Protection 2
GOOSE
MPLS
IEC 61850 Based Accelerated Line Protection
A Distance
Protection 1
A B
B Distance
Protection 1
F1 F2 F3
A Distance
Protection 2B Distance
Protection 2
R-GOOSE
IP network
R-GOOSE Control Block
UDPCOMADDR
Session User Information
Session Header
Session Identifier (SI)
Security Information
SPDU
Length
Length
Signature
domain
Session
Header
Length
LI
SPDU Length (32 bits)
Signature (size of signature +2 bytes)
PayloadLength (32 bit)
Key ID (32 bits)
SPDU Number (32 bits)
Session Identifier (SI) = 0xA0 (8 bit) - Tunnelled
0xA1 (8 bit) - GOOSE
0xA2 (8 bit) – Sample value
0xA3 (8 bit) – Management
LI (8 bit)
Initialization Vector (IV 1-233 bytes)
Version = 2 (8 bit)
Session Header Length (LI) (8 bit)
Header Content Indicator(PI) = 0x80 (8 bit)
Time of Current Key (32 bits))
Time of Next Key (16 bits)
PaddingLength (8 bits) m
Padding (0xAF)
Tunnelled
GOOSE APDU
SV APDU
Dst MAC
VLAN
IEEE 802.1p
APDU Length
APDU Length
PDUs1..n
Frame Length
GOOSE or SV
Ethertype packets
+ Ethernet Pad
Bytes
Choice of
Simulation
APPID
Simulation
APPID
Simulation
APPID
MNGT APDU
APDU Length
goosePdu
SavPdu
mngtPdu
Simulation
APPID
Padding (m bytes)
Payload
Length
PaddingLength
=m
Payload
Encrypted
domain
IEC 61850 90-5 Session Protocol
E2E Cryptographic Integrity
Propagation time measurement
Page 27
Transatlantic GOOSE latency
Page 28
One way propagation delay Texas - Austria
Page 29
Two way propagation delay Germany - Austria
Page 30