IEC 61850 GOOSE over WiMAX for Fast Isolation and
Restoration of Faults in Distribution Networks
Paper OP024
Maciej Goraj¹, Lee Lipes2, JimMcGhee2
¹RuggedCom Spain, 2RuggedCom Canada
June, 2011, Dublin, Ireland
Goals of Distribution Automation
Manual operation and slow reaction to events and
critical situations
Smarter, proactive and self-healing grid
What is necessary? • Advanced feeder automation devices located at pad-mount and
pole top systems that combine the intelligence of an RTU, relay, recloser controller, PQ meter and more.
• Broadband, long range, low latency IP and Ethernet communications network using interfaces and protocols based on power utility standards
Current situation
Future
Wireless technology is an attractive alternative if there is no existing communications infrastructure or if it is not economically feasible to
deploy fiber or broadband PLC
Device Hardware – Rugged design, IEC 61850-3, IEEE 1613 – Outdoor mounting or fit into recloser control cabinets
Power Supply – Internal power supply 12, 24, 48 Vdc – Optional support for PoE (Power over Ethernet)
Interfaces and Protocols – Ethernet and/or Serial – IEC 61850, support for L2 multicast and VLANs – Support for legacy protocols (DNP3.0, IEC 60870-5, ...)
Latency – Low latency for control signals, < 100ms
Throughput – High throughput to support non-operational data – Other potential applications: video surveillance, VoIP,
AMI backhaul, field force automation, etc.
Uplink Biasing – Configurable duty cycle, desirable up to of 75% uplink
and 25% downlink
Range – Up to 10-20km
Security – Encryption, authentication, MAC address filtering
Distribution Automation Requirements for Distribution Automation Wireless System
LTE
Microwave
Proprietary
PMP/PTP
BWA
“900 MHz”
Zigbee
802.15.4
0.1 1 10 100 1000
PAN/HAN
< 50 m
LAN
< 500m
MAN
1-20 Km
WAN
100Km
>
Data Rate in Mbps
Ran
ge /
Co
vera
ge
VSAT
WiFi
802.11
WiMAX
802.16
Cellular
(2/3G)
Comparison of Wireless Technologies
IEEE 802.16e - WiMAX
• What is WIMAX? – Non-profit industry group designed around creating an
ecosystem of interoperable wireless broadband devices
– Test for interoperability to a certain profile of IEEE 802.16e standard
– WIMAX forum certified products: http://www.wimaxforum.org/
• Quick Facts – Range up to 10- 30 km depending on path conditions and
other factors
– Throughput up to 40 Mb/s in a 10 MHz channel
– Typically point-to-multipoint with a base station serving end points. Also point-to-point or relaying architecture.
– Fixed, portable or mobile applications
– Available in licensed or unlicensed bands
• Ecosystem – Interoperability and device availability from multiple vendors, – Standards based
• Range and Propagation – Built in mechanisms to improve range over any other wireless technology
in the marketplace – Robust OFDMA technology enables non-line-of-sight (NLOS) operation
• Efficient Spectral Usage – Mobile WIMAX is built for tight frequency reuse so entire networks can be
built around small spectral allocations
• Throughput – Best in class throughput and spectral efficiency through the use of MIMO
• Quality of Service – Built-in mechanisms to support different traffic types and prioritize them
differently over the wireless network
• Mobility – WIMAX can deliver persistent connections to mobile end users
Key Features of WiMAX
There is a trade off between range, throughput and spectral efficiency and WIMAX offers the best solution to that problem
Benefits
• Own Infrastructure – Full control over the network, non-dependent on third-party providers
• Reliability & Availability – Additional security, channel availability during emergencies
• IP Based Communications – Private Broadband IP Wireless WAN and MAN
• Multiple Applications – Different applications sharing one common communications architecture
Why WiMAX for Electrical Utilities?
Disadvantages
• Spectrum Availability – Can be used in licensed, lightly licensed and unlicensed frequency bands
– Challenges due to regulatory allocation of certain frequencies
8
DHCP
ASNGW
HA
Applications Servers
cBST/pBST CPE/MSS Backbone Core Network
AAA
Management
Wired or Wireless
R4
R6
R6
R1
R1
R1
R1
R3
R3
Router
WIMAX Reference Architecture
ASN Gateway vs. Standalone Mode
• ASN gateway is a specialized router that controls the radio network
• All traffic in a WIMAX network flows through it
• Supports advanced functions like mobility, paging, etc.
• Standalone mode is a special mode of the base station that does not require ASN gateway
• Base station acts like a layer 2 Ethernet switch
• Supports only fixed applications, no mobility
CORE NETWORK
• Adjacent devices need to communicate through the ASN gateway • Difficult to predict and control end to end latency and availability • Supports only IP based traffic
ASN GW architecture fits well in mobile networks but not mission critical applications
Commercial Grade WiMAX Solution doesn’t fit Distribution Automation
ASN Gateway
Substation 1
Substation 2
R R
N/C
R R R R
R R R R N/C
N/O
N/C N/C
WiMAX
Base Station
IED
IED
IED IED
IED
WiMAX
Subscriber
Unit
Substation 1
Substation 2
R R
N/C
R R R R
R R R R N/C
N/O
N/C N/C
WiMAX
Subscriber
Unit
WiMAX Base Station
IED IED
IED
IED IED
Utility Grade WiMAX Solution for Distribution Automation
• Standalone-mode for light weight network architecture • No ASN gateway required, direct layer 2 connectivity • Cost effective, low latency, high reliability
IEC 61850 GOOSE
• Peer-to-peer (horizontal) communication
• Very fast connectionless oriented device to multi-device scheme
• Significantly reduces conventional copper wiring between IEDs
• Encapsulated directly in Ethernet layer (fast encoding/decoding)
• Event driven transmission sent on change of state
• High priority, critical, asynchronous and unsolicited
• MAC Multicast, uses VLAN for priority and traffic segregation
• Limited to LAN segment, tunneling needed to pass thru a router
Interoperable Field Proven Cost Effective
GOOSE over WiMAX
• World first project with IEC 61850 GOOSE over WiMAX, (2011)
• Peer-to-peer network operates over a private Ethernet backbone
• Decentralized restoration logic is driven down in the field devices
• With IEC 61850 distributed disconnect switches/reclosers become part of the substation
• Total end-to-end latency 30-50ms
Feeder
protection IED
WiMAX Base
Station
WiMAX
Subscriber Unit
Wireless
transmission
over several
kilometers
IEC 61850 GOOSE
Feeder
protection IED
Reclosers
Switches IED Family
+ +
Software
+
IEC 61850 over Wireless Comms
Practical Implementation
• Joint global initiative between RuggedCom and Siemens Energy
• Distribution Automation using WIMAX with IEC 61850 compliant relays
WiMAX Base Station
WiMAX
Subscriber Unit
Fault Information & Detection with GOOSE
WiMAX Base Station
WiMAX
Subscriber Unit
Status & Measured Value Sharing with GOOSE
First Deployment – Fault Isolation/Restoration
First deployment Fault isolation/ restoration scheme driven by critical loads like hospital which was manually controlled
WiMAX Rugged
Subscriber Unit powered via PoE
Switch/Recloser
Control Cabinet with IEC 61850 capable IED
Conclusions
• IEC 61850 over WiMAX improves Feeder Automation performance in Distribution Networks
• Faster fault location and restoration with reduced unnecessary switching
• IEC 61850 is interoperable, open standard based on IP and Ethernet communications
• Private communications network is more secure, more reliable and cheaper in the long term than leased services from public cellular network
• GOOSE over WiMAX is 10 times faster than GPRS, 50ms vs. 800ms
• Reduced SAIDI and SAIFI
• Increased revenue billing
• Reduced asset maintenance costs
Top Related