Protection and Control Communications with IEC 61850 1 ...€¦ · Protection and Control...
Transcript of Protection and Control Communications with IEC 61850 1 ...€¦ · Protection and Control...
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Protection and Control Communications with IEC 61850
1 – Introduction Eric A. Udren
WSU Hands-On Relay SchoolMarch 2013March 2013
Discussion leader
Eric A. Udren 43 year distinguished career in design & application of protective relaying, control, and communications systems.
Executive Advisor with Quanta Technology, LLC of Raleigh, NC in 2008.
Developing substation protection and control upgrading strategies for major North American utilities, relay application research and design, and new data communications applications.
Developed software for the world’s first computer-based relaying system.
S i d l i d t l ft d l t f th i d t ’ fi t d l t f LAN b d Supervised relaying and control software development for the industry’s first development of a LAN-based integrated protection and control system.
Designed the first interface of a microprocessor protective relay to an optical current sensor.
Developed the technical strategy for some of the most progressive utility LAN-based substation protection and control upgrading programs using IEC 61850 and other data communications, including technical design for utility enterprise integration of substation information.
IEEE Fellow.
Chairman of two IEEE Power System Relaying Committee (PSRC) Standards Working Groups
Chair of PSRC Relaying Communications Subcommittee.
Received the PSRC Distinguished Service Award in 2001 and again in 2006.
Member of IEC TC 57 Working Group 10 responsible for IEC 61850.
Technical Advisor to the US National Committee of IEC for TC 95, Measuring Relays.
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ec ca d so o e US a o a Co ee o C o C 95, easu g e ays
Member of NERC System Protection and Control Subcommittee (SPCS, formerly SPCTF).
Member of NERC Protection System Maintenance Standard Drafting Team. (PRC-005-2)
Has written and presented over 80 technical papers and chapters of books on relaying topics, and has taught courses on protection, control, communications, and integration. 2011 GA Tech PRC Walter A. Elmore Best Paper Award; IEEE Prize Paper Award.
Holds 8 patents on relaying and power-system communications.
Eric is based in Pittsburgh, PA and can be reached at [email protected] or (412) 596-6959.
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Impact of substation data communications
SUBSTA.LAN
Substation or facility local area network (LAN)
- Lack of standard protocols and
Goal 1: Collect relay data, give control for SCADA & facility operators (speed, accuracy, completeness, interoperability).
Goal 2: Access operational and non-operational data from relays or meters for many business purposes
intervendor communications was a user issue for years.
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relays or meters for many business purposes.
Goal 3: Replace wired P&C schemes with LANs.
Goal 4: Replace switchyard/power equipment wiring for instrument transformer, status, control signals with LANs.
Relay data for SCADA/EMS
RTUs connect to the same ac and apparatus signals as the relays – lots of extra wiring & electronics.
Microprocessor (µP) relays are designed for measurements status control via LAN datameasurements, status, control via LAN data communications.
Goal 1: Concentrator on LAN collects relay values and reports to SCADA & local interface computer.
Serial LAN (RS-485, multiple RS-232) still widely used.
Ethernet LAN – recommended for Smart Grid
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Ethernet LAN recommended for Smart Grid applications.
Standard protocols – DNP3/IEC 60870-5 and Modbus –serial links or Ethernet LAN.
Smart Grid standards – DNP3 and IEC 61850.
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Relay data for SCADA/EMS
Capabilities of new µP relays:
Fast response & fresh accurate data.
DNP3 and Modbus on RS-485 serial or Ethernet ports.p
IEC 61850 MMS server-client functions.
IEC 61850 GOOSE high-speed publish/subscribe of status, metered analogs, synchrophasors.
IEEE C37.118 synchrophasor streaming.
Trial in 2012 – 61850-90-5 high security WAN
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Trial in 2012 61850 90 5 high security WAN synchrophasors and wide-area GOOSE.
S b t ti
Control centers- EMS &SCADA
Planning &models
Management
Goal 2 - Enterprise information – reliability & economic benefits
SubstationLAN
CORPORATE WAN with
firewalls & push servers
Integrate relay data communications to the enterprise
Dashboard
Asset M t
Maintenance
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serversSubstation
LAN
Databases & back office applications for organizational
users
Management
Protection & Control
Engineering & models
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Relay data for non-operational users
Goal 2: Use the same communications facilities to get non-operational data to the enterprise:
Fault location, outages, failures, and system maintenancemaintenance.
Fault and disturbance recordings, event logs.
Relay and IED self monitoring and failure reporting for condition based maintenance in NERC PRC-005-2.
Performance statistics - protection & communications system management.
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system management.
Power apparatus monitoring by relays and IEDs.
Measurements for trending system operations –planning, engineering, and protection.
Substation revenue metering.
Protection & control over Ethernet LAN
Goal 3: Replace control wiring with messages on data networks.
Substations & systems with IEC 61850 GOOSE messaging on optical EthernetGOOSE messaging on optical Ethernet LANs in service.
Carry status & control points, including tripping and lockout.
High-speed analog values capability.
M & l l i l i
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Messages & relay logic replace wires, control switches, lockout switches.
Dramatic wiring reduction in the station.
Can be faster than wiring.
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Sampled Values service on process bus
Goal 4: Replace switchyard/facility wires with a few optical fibers.
Eliminate conventional cables and surge/EMI pickup
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Eliminate conventional cables and surge/EMI pickup.
Move some measurement and control closer to the power apparatus.
Move the relays away from the apparatus.
Why focus on Ethernet communications?
Important – Ethernet networks bi ti f i dcarry any combination of mixed
traffic types, protocols, services…
• Network tools to manage & prioritize mixed traffic.
• Modern Ethernet switches end old concerns about non-deterministic network traffic with collisions.
Mission critical electric tilit /ind strial applications in ser ice
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• Mission critical electric utility/industrial applications in service.
• Extra network capacity gets cheaper rapidly.
• Development of IT is crowding out other approaches.
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Big standard, evolving for 18 years and still going...
10 original parts – now in Edition 2, plus >23 new parts!
Multiple services not a monolith:
IEC 61850 ‐ Communication networks and systems for power utility automation
Multiple services – not a monolith: Server-client design for Ethernet networks.
Application layers for utility/industrial system application.
High speed protection, control, and sampled data streaming services.
System-wide data and control services and methods.
Single international standard for power system communications.
N t j t t l i l d f ti d li t d d
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Not just a protocol – includes function modeling standards.
Recognized by DOE & NIST as a Smart Grid communications backbone – NIST Smart Grid Interoperability Panel (SGIP) Category of Standards (CoS) listing.
What is IEC 61850?
A single international Ethernet based standard data communications
protocol & model structure with services and features aimed at protection
and control requirements:
Relay/IED measurement & control exchanges with substation hosts –
RTUs, concentrators, HMIs – client-server objects.
High-speed status, control, analog value transfer over LAN to eliminate
control wiring – GOOSE messaging.
Switchyard/switchgear data acquisition and apparatus control – sampled
values (called process bus).
Services for time synchronization (SNTP - obsolete), file transfer (FTP).
Reporting and configuration services
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Reporting and configuration services.
Standardized automatic configuration of substation IEDs (SCL).
New wide-area communications services.
Vision of a complete solution to replace existing diverse protocols and
communications systems.
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IEC 61850 is not just a protocol on a wire…
• A modeling approach, a system architecture, and a protocol.
• Multiple services.
Models forP&C functions &
Ti
Switchyard sampled value
streaming
IEC 61850Architecture
High-speed GOOSE control
messaging
TCP/IP
Ethernet LAN/WAN
Standardizedconfiguration process
points
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Timesynch
with SNTPCOMTRADEFault records
TCP/IP, UDP/IP, Layer 2
multicast
US approach UCA™ 21994
Evolution of IEC 61850
DNP3 becomes IEEE 1815 & stays strong
European
The international goal – agree on a single standard
US approach UCA 2
1996
One standard
IEC 61850
2000-2012
May 2000Asheville, NC
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European experienceIEC 60870-5IEC 60870-6
IEC 61850UCA 2 & IEC
61850 “merge”
IEC 60870-5 – vendors shifting support away…
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IEC 61850 wiring reduction
Integrated P&C system using fiberoptic network cables
Ethernet
Conventionalpoint to point wiring
Standardobjects
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objects,models,
& pointdescriptions Be careful – the wiring
goes away, but not the complexity...
Part 1: Introduction and Overview Part 7-4: Compatible Logical Node Classes and Data Classes
Part 7-3: Common Data Classes
Part 7-2: Abstract Communication Services
System Aspects
Part 2: Glossary
Part 3: General RequirementsPart 4: System & Project Management
Data and Services Model
IEC 61850 Edition 1 Documents
Configuration
Mapping to Ethernet
Interface (ACSI)Part 7-1: Principles and Models
Part 4: System & Project Management
Part 5: Comms. Requirements for Functions and Device Models
Part 8-1: Mapping to MMS and ISO 8802-3 (Ethernet)
Part 9-1: Sampled Values over Serial Unidirectional Point-to-Point link
Part 6: Configuration Description Language for Communication in Electrical Substations
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Part 10: Conformance Testing
Technical Report / Specification
using ISO 8802-3 (defunct)
Part 9-2: Sampled Values over ISO 8802-3Test
Electrical Substations
International Standard (IS) 9-2 LE: UCA Implementation Agreement for merging units in switchyards (LE = Lite Edition)
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IEC 61850 as multivendor standard Aims for integration of multiple vendors’
devices.
Each product has its own list of implemented
services and features.
Conformance – a product is tested to validate
that its included services conform to standard
specs.
Vendor gets KEMA, TÜV SÜD, etc. certificate.
Interoperability – two or more products actually
exchange information (no certification yet).
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exchange information (no certification yet).
Be aware of compliant creativity, generic
modeling shortcuts. Will products actually
interoperate?
Performance – a system of products performs
the application properly (no certification yet).
OSI 7-Layer Communications Stack
Layer Name Function
7 Application Meaning of the data (utility user specifics)
6 Presentation Building blocks of data and encryption for security
5 Session Opening and closing specific communications paths
4 Transport Error checking
3 Network Determining the data paths within the network
2 Li k i i d d i i h k
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2 Data Link Data transmission, source and destination, checksum
1 Physical Signal levels, connections, wires, fiber, wireless
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MMS
IEC 61850 Applications
A li ti P fil
IEC 61850 profile or stack - client-server exchanges
ISO CO Session
ISO CO Presentation
TCP
IP
RFC1006 - ISO TP0
Application Profile
Transport Profile
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Ethernet
Fiber, Twisted Pair Cu
p
Client - serverSampled
Application (Objects,Services)
IEC 61850 Communications stack mappings
Client - server communications
GOOSESampledValues
High-speed messaging on LAN – skip WAN
layers and processing
MMS
Mapping
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Ethernet Link Layer (with Priority, VLAN)
Ethernet 100 MB/s Fiber
aye s a d p ocess gdelays
TCP
IPGOOSE &Sampled Values:Layer 2 multicast
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IEC 61850 Station Bus protocol services
SCADA
Station bus mappings (8‐1)
For SCADA, protection, control, and information for the enterprise
Obj t MMS d TCP/IP l
Station Bus
SubstationHost
•Objects on MMS and TCP/IP layers
•GOOSE (on Data Link layer 2)
•Time synch (SNTP) [Later IEEE 1588/C37.232]
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Relay 3IED2Relay 1
MU - VTMU - CTProcess Bus
IEC 61850 server-client object services
The bulk of the standard (Parts 7-1, -2, -3, -4; new 7-5, new applications) describes object modeling methods.
In general, relays and IEDs are servers; higher-level computers and systems are clients.
Data messages include point descriptions or semantics – self-identifying.
Products are self-describing – aimed at making configuration faster and easier than with manual point
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configuration faster and easier than with manual point maps used with other protocols (Substation Configuration Language, Part 6).
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Object models - logical groupings
Data
Logical Device
LN2(MMXU)
LN1(XCBR)
Pos A
Ph 1 Ph 2StV q
Logical Device(1 to n)
Logical Node(1 to n)
Data Class
Data
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Physical Device(network address)Physical Device(network address)
(IED1)Physical Device
A single name always used for a particular function.
E h b i f i h
Logical Node (LN)
Each substation function may use one or more other logical nodes to perform its job (e.g., distance protection needs measurements from logical nodes CT and VT).
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L: system LN (2) M: Metering and measurement (8)
P: protection (28) S: Sensor and monitoring (4)
R: protection related (10) X: switchgear (2)
Logical node groups
C: control (5) T: instrument transformers (2)
G: generic (3) Y: power transformers (4)
I: interfacing and archiving (4) Z: further power system equipment (15)
A: automatic control (4)
Examples of Logical Nodes (LNs):
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p g ( )
PDIS: Line distance protection
PDIF: Differential protection CSWI: Switch controller
RBRF: Breaker failure MMXU: Measurement unit
XCBR: Circuit breaker YPTR: Power transformer
Disconnect sw.Q9_L1/XSWI
Grounding SwitchQ8_L1/XSWI
Logical Nodes (LN)Control
Q0/CSWIQ8/CSWIQ9/CSWI
Bay-HMIIHMI
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Primary equipmentControl house equipment
Distance ProtectionPDIS
Circuit BreakerQ0_L1/XCBR
Gas density monitoringQ0_L1/SIMS
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Accessing data
PTOCRREC
+
+IED1/XCBR.Pos
IED1
Tree view
Mode (Mode)Beh (Behavior )Health (Health)Name (Name plate)Loc (Local operation)EEHealth (External equipment)EEName (External equipment name plate)O C t (O ti t )
+
+
+
+
+
+
+
XCBR-
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OperCnt (Operation counter)Pos (Switch position)BlkOpen (Block opening)BlkClos (Block closing)ChMotEna (Charger motor enabled)CBOpCap (Circuit breaker operating capability)POWCap (Point On Wave switching capability)
+
+
+
+
+
+
+
Accessing data
Mode (Mode)+
XCBR
PTOCRREC
+
+
-
IED1/XCBR.Pos.stVal
IED1
Mode (Mode)Beh (Behavior )Health (Health)Name (Name plate)Loc (Local operation)EEHealth (External equipment)EEName (External equipment name plate)OperCnt (Operation counter)Pos (Switch position)
+
+
+
+
+
+
+
+
-
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( p )ctlValstValpulseConfigoperTimq…more
intermediate-state (0)off (1)on (2)bad-state (3)
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Helpful explanation of 61850 modeling
By Karlheinz Schwarz
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By Karlheinz Schwarz, Netted Automation GmBH
Seehttp://www.nettedautomation.com/qanda/iec61850/information-service.html#Q1
Example:
Substation (S151) – Voltage level (E1) – Bay (Q3) Physical Device (BC) – Logical Device (CTR)
Hierarchical standard object naming
<prefix> <Logical Node> <instance>
Data description (from common data class, CDC)
Attribute – the current value
In MMS notation: S151E1Q3 $ BCCTR $ Q0XCBR1 $ Pos $ ST$ stVal
Interpretation: (Substa-V-bay) . (Physical box, and functional l i hi h h b k i ) (I f B k
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element within that has breaker image) . (Image of Breaker Q0) . (Data name Pos is position value) . Functional Constraint ST (a momentary status report only) . [the status value report – transition, open, closed, invalid]
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LN example – control, breaker, voltage reg.
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Note generic LNs – manual config. – versus std. defined LNs supporting auto config.
Time synchronization
IEC 61850 specifies simple network time protocol (SNTP) from the IT world.
Accuracy assured only within a few milliseconds y y(although some claim better recently).
Requirement for time stamping of events and oscillographic records is 1 ms (from NERC, for event analysis)
Requirement for time synchronization of waveform
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equ e e t o t e sy c o at o o a e osampling for process bus merging units is 1 to 10 microseconds, tighter for synchrophasors.
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Time synchronization
The practical solution – wired IRIG-B or fiber connections of time synchronization signals directly from GPS clock IED to IEC 61850 servers and clients.
Same as non-61850 practice
Leaves a few wires in an otherwise clean design
IEEE 1588 – a new standard for time synchronization on a LAN with sub-microsecond accuracy – IEC 61850 profile started at IEEE PSRC WG H7.
PC37 238 IEEE 1588 Profile for Protection Applications
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PC37.238 IEEE 1588 Profile for Protection Applications
Configuration with 61850-6 SCL tools
Unified configuration of entire facilities via XML file process – even over wide area.
Not exactly plug-and-play.
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Functional specifications & design standards
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Some configuration tools
Siemens DIGSI (oldest)
GE EnerVista (umbrella for many functions; SCL added)
SEL AcSELerator Architect
ABB ITT Integrated Toolset (recent benchmark, but only ABB)
Applied Systems Engineering (ASE) Visual SCL
Triangle Microworks SCL File Editor, Anvil, Forge…
Kalkitech SCL manager
Helinks (from 61850 developers)
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Grid Smart 61850easy – handy diagnostics
Tools are biggest challenge – area of active work and user complaints.
2 - GOOSE Messaging and Networks
Protection and Control Communications with IEC 61850
Eric A. UdrenWSU Hands-On Relay School
March 2013
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Fast relaying over Ethernet LAN
From Part 1 -
Goal 3: Replace control wiring with messages on data networks.
Logic in the relays exchanges messages overLogic in the relays exchanges messages over high speed redundant optical LANs to replace wires, control switches, lockout switches.
Dramatic wiring reduction in the station.
Many installations designed with IEC 61850 GOOSE messaging on LANs are in service.
Status points control including tripping and
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Status points, control including tripping and lockout, high-speed analog values.
Can be faster than wiring.
Role of IEC 61850 GOOSE messaging
IEC 61850 GOOSE messaging provides:
High-speed peer-to-peer transfer of status/control bits (reporting
contact state over a wire) or analog values including synchrophasors
for protection and control.
GOOSE messaging plus programmable logic in relays and IEDs
replaces panel wiring and controls.
Benefits – wiring and control elimination, panel and floor space
reduction, less equipment overall in P&C system, continuous
monitoring and management of the system design (“wiring”)
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monitoring and management of the system design ( wiring ).
Works with other IEC 61850 services, or without them (e.g., with
60870-5 or DNP3 polling for SCADA)
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61850 GOOSE and GSSE messaging
Generic Object Oriented
Substation Event.
A relay or IED can send a y
sequence of control, status point,
or analog value messages to
replace control and measurement
signals on dedicated wires.
Not just a single message to request remote action…
A process to “continuously” send intended state from
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A process to continuously send intended state from
transmitting IED – like a contact that picks up and drops out
at critical moments.
Even if a subscribing (receiving) relay is just powered up, it
can get updated status it needs.
GOOSE Protocol in 61850-8-2
Application layer directly accesses link layer for speed – no TCP/IP
Uses Ethernet frame directly with Priority/VLAN 802.1Q tag
Use priority ≥4 due to criticality or messages.
VLAN use is optional.p
Fields in payload - source ID, status bits, analog values, time stamp, sequence number, time to live, quality bits, test modes.
Typical packets 200 – 300 bytes long.
Ethertype (8100 = Ethernet
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Publisher-subscriber exchange:
Each relay publishes a continuous stream of packets with values that others might need.
Overview of GOOSE messaging
Any other relay or IED can subscribe to (view contents from) the streams it needs.
Publisher just talks – does not know who subscribers are, or whether they got the messages in the stream.
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Overview of GOOSE messaging
Adaptive rate of GOOSE message transmission:
• Time values are examples in standard – manufacturers vary.
• Some let you set base heartbeat rate and acceleration profile.
• Heartbeat reports values during quiescent times:
Communications monitoring by all subscribing relays
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– Communications monitoring by all subscribing relays.
– Update of latest status in case of any relay on the LAN that was
just turned on.
• Modern LAN with Ethernet switches handle all the messages even for
a worst-case power system event.
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GOOSE packet rates
SEL example, set 1 s heartbeat:
Message b
Interval from i
Time k
GE UR V5.70 example:
number previous, ms mark, ms
1 N/A 0
2 4 4
3 8 12
4 16 28
5 32 60
6 64 124
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6 64 124
7 128 252
8 256 508
9 512 1 s
Did the GOOSE messages arrive?
Publisher-subscriber exchange:
• Unconfirmed service, backed up by:
Constant repetition or updating– Constant repetition or updating.
– Redundancy in LAN and relaying
architecture.
– Monitoring and alarming by subscriber
IEDs that fail to receive publisher’s
message stream – call maintenance for
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repair.
Wires cannot continuously monitor
themselves as GOOSE messages can do!
© 2011 Penwell & Quanta Technology LLC
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Analog GOOSE messaging
Concept - send analog values with same millisecond exchanges as for status or control points.
Change events defined by settable measurement Change events defined by settable measurement deadband.
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Multiple values in one GOOSE packet.
Analog GOOSE messaging
Products today:
Send analog values at a fixed slower rate – 100 ms or 250 ms – not as useful for relaying as GOOSE t t i tstatus points.
Some will send values at rate driven by status points in message, but analogs are repeated and updated every 100 to 500 ms.
NEW: publish synchrophasor values at a rate of 2 to 4 per second (GE and SEL) - Synchrophasor time
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4 per second (GE and SEL) Synchrophasor time tags in packets.
Ask vendor how to get at GOOSE time tag – not the same as synchrophasor time tag.
This GOOSE is too slow for high speed WAMPAC.
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Speed of GOOSE messaging
GOOSE message control can be faster than a wired connection! Save 1-4 ms. How?
A wired trip signal goes through:
The relay processor output program loop delay.
Output delay of hardware interface to wires.
Input debounce filter delay of receiving relay.
Signal waits milliseconds for the input processing
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g p p gprogram logic loop to notice it and react.
GOOSE message bits are sent and read directly between relay processors with microsecond Ethernet delays.
Products vary – ask manufacturer, or test.
Electromechanical lockout switch drawbacks
Adds 1 cycle operating time.
Funnels wiring from bus full of breakers into one panel location.
A lot of wiring.
Wiring reflects and must adapt to changes in substation topology or relaying philosophy.
Rarely operates in normal service j d d ’t t i
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– some jam and don’t trip.
Dangerous testing challenge -NERC says test it.
Big cost adder to scheme –deterrent to differential relay use.
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Distributed lockout with GOOSE
Each relay with relevant breaker control keep track of lockouts in effect, by logic programming.
Relays are coordinated by the lockout initiating relay, or b t ti t l k t it f tiby a station computer lockout monitor function.
Each relay has a nonvolatile memory of lockout state (some use mechanically latched output relays).
Uses messaging capabilities already in new relays.
No extra wiring or cost.
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Self monitoring feature eliminates testing problem.
As fast as direct tripping.
See 2009 NETAWorld article by Myrda, Donahoe, Udren for design example.
Ability to trip is monitoredEnd-to-end check of GOOSE communications:
Transformer relay publishes a GOOSE message including a bus breaker trip bit.
Normal-state message (do not trip) is generated every second by DSP in transformer relay.
Passed through communications network to bus relay DSP
Bus relay DSP alarms if no-action message disappears.
Wires cannot check themselves this completely!
Line RelayBus Relay
System A
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System ASystem A
Xfmr Relay
System A
Monitor IED
System A
Ethernet Switch
System A
52TC
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Engineering of mission
Redundant station bus for IEC 61850 GOOSE messaging
Engineering of mission critical substation Ethernet network
No single point of failure within each of dual redundant LANs.
Use relay primary and f il ti l Eth t
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failover optical Ethernet ports.
Dual switches and paths for GOOSE messages.
Multicast GOOSE messages have no destination address
Designed to stay within a LAN or Virtual LAN.
Do not pass through routers to the WAN or other LANs.
GOOSE and wide area networks
But –routers make secure bridged connection between two LANs separated by a WAN – works like one big LAN.
Useable for transfer tripping, monitoring, control or load mitigation via WAN.
Need cyber security – VPN, firewalls, etc.
Slows down messaging today 20 ms getting faster
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Slows down messaging – today 20 ms, getting faster.
See IEC 61850-90-1 for teleprotection over WAN examples.
See 61850-90-5 for new GOOSE streaming over WAN.
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Settings management
Need a closed-loop business process that initiates and tracks all installation and updating of setting records.
Communicates with the IEDs themselves (over WAN is future method) to check consistency between the data base and the installed settings and firmware.
Need a convenient way of installing settings within the management system in every use case.
Firmware update, maintenance check, operating emergency, relay replacement, etc.
New software data base tools can connect with tested d i t t i t d f t
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devices, test equipment, and enforce management processes – OMICRON, EnoServ, IPS, others.
This is a big need for all 61850 services and systems, and all new complex relays and IEDs!
Using 61850 services on the LAN
Use client-server exchanges of standard defined objects for metering, status, control, and IED configuration.
Metering and status via polling or report-by-exception.
No visible impact on installation – benefit is drive to easy No visible impact on installation benefit is drive to easy engineering and maintenance.
DNP3 can perform similar role with familiar manual point configuration lists.
GOOSE messaging and Sampled Values service get rid of conventional control wiring among relays, IEDs, power apparatus –design commitment; visible change.
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DNP3 has no high speed data or control ability like GOOSE or Sampled Values
New – 90-5 R-GOOSE and R-SV over WAN.
LAN can carry mixed traffic – e.g. DNP3 metering and status, non-61850 legacy device traffic, plus GOOSE for wiring elimination.
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Protection and Control Communications with IEC 61850
3 - Recent Developments in IEC 61850Eric A. Udren
WSU Hands-On Relay SchoolMarch 2013
IEC 61850 is living and growing
IEC 61850 Edition 1 – the seed – 1700 pages
IEC 61850 Edition 2IEC 61850 Edition 2
International application –improved models
Expanded structure
Improved clarity
TISSUES (b ) l d
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TISSUES (bugs) cleared
New practical features
New application domains
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IEC 61850 is branching
New parts of IEC 61850
Expanding outside the substation Between substationsBetween substations
To control centers
Communications and application modeling across the entire power system
Integration with enterprise systems
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systems
Interfaces with popular SCADA and control protocols
Wide-area high-speed data & control services with security
What is new in Edition 2 of existing parts?
Clarifications and corrections (TISSUES)
Modeling
Power Quality
Statistical evaluation of information
New models for mechanical equipment and measurements of non-electrical quantities
New features for testing support
Support for exchange of engineering information for configuration across projects and between facilities
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configuration across projects and between facilities
Redundancy – possibility to have IEDs with dual connections
30
Testing improvements
• Edition 1 required expedient user construction of testing facilities (mainly with GOOSE).
Edition 2 –
/f f• Mirroring/feeding back control information
• Isolation of functions in service
• Interlocking test methods
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IEC 61850 – new parts
New facilities modeling:
IEC 61850-7-410 – Hydroelectric power plants –Communication for monitoring and control
IEC 61850-7-420 – Communication Systems for Distributed Energy Resources (DER)
IEC 61850-7-500 /-7-510 (Technical Reports)
Explains how to use the concepts of IEC 61850 to model applications
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IEC 61400-25-x – Communications for monitoring and control of wind power plants
31
More new parts under development
Part 7-5 - defines the usage of information models for substation automation applications - examples on how to apply logical nodes from 7-4 for various applications.
Part 7-10- web based IEC 61850 models
More consistent implementations than those from programmers reading paper documents.
Part 100-1 - Methods for functional testing in IEC 61850 based systems.
Configuration management of IEC 61850 based systems
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Configuration management of IEC 61850 based systems
Mappings for gateways
IEC 61850-80-1 – Guideline for exchange information from a common data class (CDC) based data model using IEC 60870-5
Station Controller & Gateway
60870
61850
data model using IEC 60870 5
IEC 61850-80-2/IEEE 1815.1 – Exchanging Information between networks implementing IEC 61850 and IEEE 1815 (DNP3)
DNP Master
DNP Outstation
Bay Controller
61850
Protection
61850
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(DNP3) Just starting – IEEE C37.118
synchrophasors to IEC 61850-90-5 synchrophasors – at PSRC
IEC 61580 Client
IEC 61850 Device
IEC 61850 Device
IEC 61850 Device
IEC 61850 Device
Gateway
32
How to address new areas?
Technical reports explain “How to use IEC 61850 for...“
Technical reports describe:
The use cases considered
The impact on the communication
The impact on the modeling
The impact on the engineering
Results will be used to update the standards later. ( d t diti )
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(amendments or new editions)
Technical reports (not standards)
IEC 61850-90-1: Using IEC 61850 for communication between substations (published)
IEC 61850-90-2: Using IEC 61850 for communication b t b t ti d t l tbetween substations and control center
IEC 61850-90-3: Using IEC 61850 for condition monitoring
IEC 61850-90-4: Network engineering guidelines
IEC 61850-90-5: Using IEC 61850 to transmit h h i f ti di t IEEE C37 118
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synchrophasor information according to IEEE C37.118
Really important – how to stream sampled values, synchrophasors, or GOOSE messages over WAN with security using standard IT services
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90-1 on interstation communications
61850 communications, modeling/semantics, & system engineering across stations need Ethernet communications. GOOSE needs LAN, or equivalent…
Ethernet between stations:
Wideband direct interfaces of LANs
Tunnel that filters and directly passes packets over WAN
Gateway that acts as a proxy for packets – e.g. teleprotection device
Ethernet LAN/WAN configuration advice
Station A Station B??
Teleprotection equipmentacting as gateway
?
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Function A1
Function A2
Function B1
Function B2
Transparent Tunnel
??Proxy
B1
?
61850-90-2 and 90-3
90-2 - Using IEC 61850 for the communication between substations and control centers – in development
90-3 – Condition monitoring of primary power apparatus –communications & asset management requirements:
Transformers, LTCs
GIS
Lines, UG cables
Sta. batteries
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Part 90-4 - Network Engineering Guidelines
Ethernet network& physical layers were black box – you make it work.
Now – comprehensive guidance on reliable network design.
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Part 90-4 - Network Engineering GuidelinesLayer 2 redundant network paths for protection messages
Short-bump or bumpless rerouting for segment failures
62439-3 Parallel Redundancy Protocol (PRP) – 2 LANs
62439-3 High availability Seamless Redundancy (HSR)
Rapid spanning tree protocol (RSTP) from IT and redundancy – simple and fine!
DANH
CPU
DANH
CPU
source
„A“-frame(HSR)
„B“-frame(HSR)
destinations
„C“-frame „D“-frame
DANH
CPU
DANH
CPU switch
RedBox
singly attached nodes
interlink
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DANH
CPU
DANH
CPU
DANH
CPU
DANH
CPU
DANH
CPU
DANH
CPU
DANH
CPU
DANH
CPU
DANH
CPU
DANH
CPU
destinations
35
90-5 WAN synchrophasor transport
Sampled Value or GOOSE publish/subscribe across the WAN – useful way beyond just synchrophasors.
Add layer 3 transport – UDP/IP unicast or multicast (unconfirmedefficient stream of data packets – not like slow, confirmed TCP/IP)p , )
Routers can search for subscribers and establish routes dynamically using Internet Group Management Protocol (IGMP) V.3, a standard IT router service.
New - a big deal – end-to-end authentication in the packet!
SHA-2 authentication hash code - computed in real time.
Needs new PMU/relay platforms/processors to compute
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Needs new PMU/relay platforms/processors to compute authentication hash code (coming in 2012).
Industry standard Group Domain of Interpretation (GDOI) security key distribution/management.
Packet encryption specification – can be done in routers.
WG17 technical reports - SG integration
• IEC 61850-90-6: Using IEC 61850 for distribution automation.
• IEC 61850-90-7: IEC 61850 object models for photovoltaic, storage
and other DER inverters.
• IEC 61850-90-8: IEC 61850 object models for electrical vehicles.
• IEC 61850-90-9: IEC 61850 object models for battery storage systems.
• IEC 61850-90-10 – DER scheduling.
• IEC 61850-90-11 – Modeling of
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IEC 61850 90 11 Modeling of
programmable logic per IEC 61499.
• IEC 61850-90-14 – Modeling of FACTS
power controllers
36
IEC 62445-2 Standard for communications between substation and control center.
C C f C
Other standards projects supporting IEC 61850
IEC 62351-6 - Cyber security structure for IEC 61850.
Harmonize data models of IEC 61968 Common Information Model [formerly EPRI CIM] and IEC 61850.
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Product development
61850 compliant relays and IEDs are widely available.
It’s been a long expensive road for manufacturers – they are committed to development.
See http://www.ucausersgroup.org/ for list of compatible d t d th i f tiproducts and other information.
In early 2012 – lots of servers (relays), growing choices for clients (substation hosts), emergence of commercial process bus (sampled data) systems based on IEC 61869-9.
Learn status at UCA International Users’ Group http://sharepoint.ucausersgroup.org/default.aspx
Reports and related standards developments at IEEE Power S t R l i C itt (PSRC) ti
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System Relaying Committee (PSRC) meetings http://www.pes-psrc.org/
Articles in PACworld magazine http://www.pacw.org/home.html
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IEC 61850 – supported in products
Embeddable stacks for sale to IED manufacturers – Triangle Microworks and SISCO.
Supported by IED manufacturers – SEL, GE, Siemens, ABB, Alstom Grid/Schneider, ZIV, RFL, Ametek Pulsar, others.
R l t t t f t i t d i 61850 d t Relay test set manufacturers introducing 61850 products –OMICRON, Doble, Megger, others.
Industry-standard conformance testing program per 61850-10 and UCAIUG program with laboratories.
Substations with significant 61850 in North America since 2005 – going into design standards at large utilities.
Used in critical special protection schemes.
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IEC 61850 versus DNP3
DNP3 Pros –
IEEE 1815 standard, long complete (according to its own targets)
Widely sold and used
IEC 61850 Pros –
Single international Smart Grid integration standard suite
All required services
All major vendors support Widely sold and used.
Debugged, stable
Supported by Users’ Group
DNP3 Cons –
No high speed control or data services,
Just for SCADA
High-speed control (GOOSE) and process data (Sampled Values) including wide-area and security
Models the functions for automated integration process (little hand configuration)
Supported by Users’ Group
IEC 61850 Cons –
Integration tools have been work in progress
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Just for SCADA
Manual configuration of points and data types takes time.
Mostly North American
Integration tools have been work in progress for a long time
Interoperability work in progress
Big product development effort, depending on scope focus.
Design for usability and maintenance is an area of opportunity
38
Troubleshooting Ethernet/61850 systems
Function level monitoring - program the relay logic to report data sent/received – catches most problems!
This is an IT network.
Basic tools for Ethernet networks – e g WireShark Basic tools for Ethernet networks – e.g., WireShark
Protocol-specific tool examples:
Applied Systems Engineering DNP3 Analyzer
SMC 61850 GOOSEMeter (hand tool)
61850Easy configuration/troubleshooting tools
SISCO AXS4MMS Client - analyzer for relays (servers).
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SISCO GOOSE Blaster simulator
NetScout network traffic monitoring for GOOSE
Most important – design functional test features into the logic.
61850 progress
Massive standard – growing beyond 2000 pages (users don’t need to read all this).
Continuing development and issue resolution among vendors users and standards developersvendors, users, and standards developers.
Edition 2 and new parts of 61850 are being published.
Supported by today’s major relay vendors.
Paper and article traffic reaching saturation level.
Varying interpretations by vendors require industry conformance test program
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conformance test program.
61850 reaches inside the devices – there are problems – get experienced guidance for standard development.
DNP3 remains a widely used client-server protocol that works on Ethernet (hand point map; no GOOSE).
39
Steps of typical IEC 61850 project
Each utility has unique organization and needs
1. Data gathering – engage all stakeholders up front!
2. Develop specifications.
3. Develop Request for Information (RFI) with specs.p q ( ) p
4. Conduct RFI & process – get back a practical plan?
5. Business case - justify proceeding?
7. Full specifications.
8. RFP & vendor selection for trial standard system.
9. Detailed design with vendors.
10. Organizational design and preparation.
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10. Organizational design and preparation.
11. Development lab, training facilities.12. Field trials.
13. Standards development; procedures and documentation.
14. Interface systems to the utility enterprise.
Protection and Control Communications with IEC 61850
4 - Sampled Values Service & Process BusEric A. Udren
WSU Hands-On Relay SchoolMarch 2013
40
Sampled Values service for process bus
If a LAN can carry critical relaying traffic in the controlh it d t dhouse, can it carry data andcontrol between the switchyardand the control house?
Goal 4: Replace switchyard wires with a few optical fibers.
Eliminate conventional cables and surge/EMI pickup.
Move some measurement and control out to the yard, closer to the power apparatus
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power apparatus.
Just a few wires left - we still have to get dc and station service power out to the yard.
Process bus
Voltages, currents, and status sampled near the source and converted directly to Ethernet packet stream.
Multiple sample sets per packet for data transmission efficiency.
Support trend towards intelligent power apparatus - relays, metering, control IEDs installed directly in the power apparatus, even in the factory.
Reduce field wiring cost.
Cut wiring losses and burdens.
Add field signals without new wiring to control house.
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41
Process Bus concept
µP1 OR
MORE
A/DSub-
systemCTs,VTs
LP FILTER
LP FILTER
LP FILTER
LP FILTER
MUX
SAMPLE AND
HOLD
Ethernet Network Communications
If we cut a microprocessor based relay in two and put a communications bus between the I/O and the processing...
Comm.Controller
A/DSub-
systemMUX
S/H & Filter
S/H & Filter
S/H & Filter
S/H & Filter
O/E
SubstationLAN
Control House Switchyard
VTsRelay Output
Relay Output
Relay Output
Trip andalarmcircuits
Contact Inputs
Statuscontacts
POWER SUPPLY
125 Vdc Station Battery Supply
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µP Comm.Controller
µP Comm.Controller
O/E
Relay Output
Combining data from diverse locations around the switchyard
Process Bus LAN
Comm.Controller
A/DSub-
systemMUX
S/H & Filter
S/H & Filter
S/H & Filter
S/H & Filter
Relay Output
Optical fibers
Process bus services in 61850-9-2
•Sampled values protocol (on data link layer 2 for speed and simplicity)
•GOOSE (on data link layer 2 for d d i li i )
SCADA
speed and simplicity)
•Time synch (SNTP)
Relay 3IED2Relay1
Station Bus
SubstationHost
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yIED2y
MU - VTMU - CT Process Bus
MU = switchyard Merging Unit
42
Line Protection Bus Protection
EthernetController
EthernetController
Merging unit
Merging Unit
Ethernet Controller
IEC 61850-9-2 Process BusBinary Inputs &
Control Outputs
Ethernet Switch
C37 92 OVT
Sample timing synchronization
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withCombined
ECT and EVT
MOCT fiber
EOVT fiber
Conventional VTs
Conventional CTs
C37.92 OCT
C37.92 OVT
Process Bus Protocol in 61850-9-2
Application layer directly accesses link layer for speed – same as GOOSE
messaging – no TCP/IP
Uses Ethernet frame directly with priority/VLAN .1Q tag
Use priority ≥4 due to criticality or messages, same as GOOSEp y y g ,
VLAN use is optional
What goes into the packet payload?
Ethertype (8100 = Ethernet
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43
IEC 61850-9-2 frame – generic and flexible
Octets 8 7 6 5 4 3 2 1 Notes
Preamble
Start of frame 0 1 2
23 4 5
Destination address
6 7 8 9
10 11
Header MAC
Source address
Refer to “AddressFields” section.
12 13
TPID
14 15
Priority tagged
TCI
Refer to ”Priority Tagging/VirtualLAN
section.
16 17
Ethertype
18 Length Start 19
APPID
20 Ethertype PDU
Octets 8 7 6 5 4 3 2 1
1
2 TPID
0x8100 (802.1Q Ethertype)
3 User priority CFI VID
4 TCI
VID
Service Default VID Default priority
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2021
Length (m + 8)
22 23
Reserved 1
24 25
Reserved 2
26 .
m + 26
APDU (of length m)
Ethertype PDU
Refer to “Ethertypeand Other Header
Information” section.
. .1517
(Pad bytes if necessary)
.
.
. .1521
Frame check sequence
Service Default VID Default priority
Sampled Values 0 4
9-2 LE Implementation Guideline
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IEC 61850-9-2 LE Data Set
Fixed sampling rates of 80 or 256 samples per power cycle at 50 or 60 Hz.
Fixed data frame format
Fixed configuration format
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9-2 LE fiber 1 pps synchronizing clock input specs
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Unified substation-wide LAN using 9-2 LE
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Chopping up the ring for redundancy
Design concept of big ring station/process bus does not separate the zones
of protection – zones share merging units and communications.
Relay engineers are used to separating zones of protection for reliability &
failure mode handling.g
Another way to apply MUs –
dedicated merging unit
function for each zone,
each location, and
System A or System B
– full redundancy and
isolation.
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isolation.
This takes a lot more
equipment but
separates zones.
46
Another direction – 61850-9-2, but not 9-2 LE
GE Multilin HardFiber® process bus system.
Uses conformant 61850-9-2 sampled values frame.
Uses 61850-8-1 GOOSE for sampling synchronization and control .
61850-8-1 GOOSE is not how 9-2 LE synchronizes sampling – not compatible with other vendors’ MUs.
Technically thoughtful (an opinion) architecture solution that addresses application concerns:
Isolation of protection zones.
Isolation of redundant systems.
Works ith toda ’s GE UR rela s
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Works with today’s GE UR relays.
Each relay drives its own data sampling, as it does conventionally.
Tracks system frequency and avoids distance relay polarizing problems.
Design includes solutions to installation efficiency and testing issues.
GE HardFiber® process bus system
Weatherproof Brick® mounts on apparatus; has four mini merging units inside – GE calls them cores.
Connect to relays in control house via premade fiber assemblies and weatherproof connectors. eat e p oo co ecto s
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Images courtesy GE Multilin
47
GE HardFiber components
GE prefab multiple fiber plus power cable from Brick to SCE relays in SCE facility.
Variety of standard lengths up to 500 meters.C il th bl h
GE prefab copper cable for field connections –CTs, PTs, contacts, trip circuits.
Coil the excess cable where convenient.
Brick end and indoor end shown.
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Images courtesy GE Multilin
GE HardFiber components
Indoors:
Cross connect panel.
Fibers to/from relays.
Power from panel to remote Brick via HardFiber cable.
Flexible easy patching of Brick
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patching of Brick cores to multiple GE UR relays.
Images courtesy GE Multilin
48
GE HardFiber components
Process card replaces UR analog/binary input card.
A special purpose Ethernet switch connecting multiple brick core fiber signals to the protection processor.
NOTE: No network connection is possible to existing UR Ethernet port used for:
IEC 61850 GOOSE messages to control center.
Relay settings, events, or configuration.
Isolated by protection application processors.
Can’t hack from Brick into substation network.
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Critical CIP compliance help.Image courtesy GE Multilin
GE HardFiber system configuration
Sampling is triggered by downward GOOSE messages, not 1 pps timing fibers across switchyard.
Electronic data sources are not shared across zones or between redundant systems.
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Image courtesy GE Multilin
49
HardFiber interoperability with other vendors?
ABB, Siemens, Alstom Grid, SEL used 9-2 LE.
9-2 LE is an implementation id li t t f 61850 t d dguideline, not part of 61850 standard.
Brick cannot work in a 9-2 LE system & vice versa.
What about multiple vendors and interoperability of 61850?
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2012 - a way out of the impasse
Merging unit standards project in IEC TC 38 (Instrument Transformers) – IEC 61869-9 Merging Unit Standard.
IEC 61869-9 cites 61850-9-2 and chooses specific options – one sampling rate only (4 kHz), standard frames, etc. – even more specific than 9-2 LE.
Eliminates 1 pps fiber time synchronization - IEEE 1588 precision timing protocol (PTP) on the existing Ethernet connection to synchronize samples.
Every vendor can adapt its products to work with this standard without big hardware changes.
GE and the others said they will adapt to published standard
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GE and the others said they will adapt to published standard.
Products interoperate, with flexible architectures.
Implementation agreement in drafting.
50
Ngrid UK 400 kV process bus demo
Ratcliffe indoorsubstation
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Switchyard maintenance solution!
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Cost effective partial solution
Extend the station bus into the switchyard for binary status and control I/O.
Put a remote binary I/O relay (SEL 451, GE UR C90+, etc.) in the switchyard for all status and control via GOOSE.
Wire only the CTs and CVTs back to the control house.
Eliminate 70-80% of switchyard wiring.
We can do it right now.
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Solution for NU 61850 EHV P&C design standard.
Questions?
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[email protected] or (412) 596-6959.