Comparison_DNP_60870_61850
description
Transcript of Comparison_DNP_60870_61850
2002-02-02 © SCC 2002 Page 1 of 20
Comparison of IEC 60870-5-101/-103/-104, DNP3,
and IEC 60870-6-TASE.2 with IEC 618501
Karlheinz Schwarz, [email protected]
www.scc-online.de February 02, 2002
1 Executive SummarySCADA protocols have traditionally been designed to optimize bandwidth (num-ber of bytes on the wire) and hardware utilization (processor speeds, RAM andROM space). IEC 60870-5 and DNP3 emerged from a broad family of proprietaryprotocols for Data Acquisition (Data Collection) to provide a first level of DataAcquisition Interoperability.
Increased number of points implies higher costs for maintaining databases, com-missioning costs in verifying points. More applications are accessing the data andthe complexity of the applications has increased. Deregulation will only add to thecomplexity through increased information sharing. With traditional SCADA proto-cols the meaning of the points is located in various places: configuration of RTUand/or IED, configuration of databases, and configuration of applications. TheManagement of this complex information (definition, validation, interpretation, anduse) is costly and time-consuming. Easier Management and Integration of theInformation has become a crucial requirement. Technology advancements inhardware, software, and communications has shifted the focus in SCADA appli-cations from Data Acquisition to Information Management.
IEC 618502 meets the requirements for an integrated Information Management,providing the user with consistent Knowledge of the System on-line – ratherthan just Gigabytes of raw data values. IEC 61850 defines standardized Informa-tion Models across vendors. Self-description and Meta-Data allow for on-lineValidation. Objects are accessed by name, rather than user/vendor/model specificpoint numbers. Thus Database Validation can become highly automated, withoutvendor configuration files.
1 This is the 2nd version of the comparison; the first (2001-08-28) has been revised and enhanced (DNP3).2 IEC 61850 is mainly based on UCA™ (IEEE TR 1550). For the purpose of this comparison, UCA is understood asa synonym of IEC 61850. UCA is a Trademark of EPRI, Palo Alto (CA)/USA.
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Standardized Information Models, a set of appropriate real-time SCADA Serv-ices, and the application of advanced communication systems allow for a highlevel Application Interoperability providing application domain specific informa-tion models (semantic of data) rather than interoperable data exchange services. Inthis regard, IEC 61850 goes far beyond the traditional SCADA protocols.
The specific definitions in IEC 61850 provide Information Models for substationsand feeder applications. The common parts are used as a base standard in otherapplication domains, e.g. distributed Energy systems (IEC TC 88 - Wind powerplants; IEC 61400-25).
IEC 61850 will very likely become the solution for a single IEC TC 57 SeamlessTelecontrol Communication Architecture (sTCA). SCC expects that this willcause most new substations to be specified with IEC 61850.
2 MotivationUsers and vendors of IEC standard and DNP compliant power system productsask more frequently why the IEC TC 57 (Power systems control and associatedcommunication) will publish a new International Standard for real-time commu-nication (IEC 61850) soon.
Many experts guess that IEC 61850 is just another IEC SCADA protocol. It seemsto be crucial to show the commonalties and what distinguishes IEC 61850 fromthe traditional approach.
3 ObjectiveThe objective of this analysis is to provide a comprehensive comparison of theavailable IEC standards and DNP3 specification with the new standard IEC 61850(see chapter 4 for full titles):
— IEC 60870-5-101 Companion standard for basic telecontrol tasks
— IEC 60870-5-103 Companion standard for the informative interface of protec-tion equipment
— IEC 60870-5-104 Network access for IEC 60870-5-101 using standard trans-port profiles
— DNP3 Distributed Network Protocol (DNP)
— IEC 60870-6 Telecontrol equipment and systems - TASE.2 (synonymICCP – Inter-control center communications protocol)
— IEC 61850 Communication networks and systems in substations(UCA™)
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The comparison in chapter 6 shows what the solutions have in common, how theydistinguish, and what the main benefits and advantages of each solution are.The analysis addresses seven areas of interest:
1. General issues (Table 1)2. Process data description (Table 2)3. Operational services (Table 3)4. Selfdescription services (Table 4)5. Online configuration (Table 5)6. Offline configuration (Table 6)7. Integration into Applications (Table 7)8. Architecture and communication stacks (Table 8)
Chapter 7 provides a summary.
Acknowledgement
The analysis is based on the experience and background information of well knownexperts (convenors and other working group members) that are involved in severalIEC TC 57 projects, UCA™, and DNP for many years.
I would like to thank
— Wolfgang Brodt, Convenor IEC TC 57 WG 03; (SAT, Vienna/Austria), — Christoph Brunner, Convenor IEC TC 57 WG 12; (ABB, Zurich/Switzerland), — Grand Gilchrist, Secretary, DNP User’s Group Technical Committee and Mem-
ber of IEC TC57 WG 10,11,12 and 15; (GE Energy Services, Calgary/Canada),— Wolfgang Maerz, speaker of German delegation of IEC TC 57; (RWE, Dort-
mund/Germany), and— George Schimmel, Convenor IEC TC 57 WG 11; (Tamarack, Ann Arbor
(MI)/USA),
for their review that made this comparison possible.
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4 ReferencesThe following documents – among others – have been considered.
— IEC 60870-5-101 Telecontrol equipment and systems - Part 5-101: Transmis-sion protocols - Companion standard for basic telecontroltasks
— IEC 60870-5-103 Telecontrol equipment and systems - Part 5-103: Transmis-sion protocols - Companion standard for the informative in-terface of protection equipment
— IEC 60870-5-104 Telecontrol equipment and systems - Part 5-104: Transmis-sion protocols - Network access for IEC 60870-5-101 usingstandard transport profiles
— IEC 60870-6-503 Telecontrol equipment and systems - Part 6: Telecontrolprotocols compatible with ISO standards and ITU-T recom-mendations - Section 503: TASE.2 Services and protocol
— IEC 60870-6-802 Telecontrol equipment and systems - Part 6: Telecontrolprotocols compatible with ISO standards and ITU-T recom-mendations - Section 802: TASE.2 Object models
— IEC 61850-7-1 Communication networks and systems in substations - Part7-1: Basic communication structure for substations andfeeder equipment - Principles and models
— IEC 61850-7-2 Communication networks and systems in substations - Part7-2: Basic communication structure for substations andfeeder equipment - Abstract communication service interface(ACSI)
— IEC 61850-7-3 Communication networks and systems in substations - Part7-3: Basic communication structure for substations andfeeder equipment - Common data classes
— IEC 61850-7-4 Communication networks and systems in substations - Part7-4: Basic communication structure for substations andfeeder equipment - Compatible logical node and data objectaddressing
— IEC 61850-8-1 Communication networks and systems in substations - Part8-1: Specific communication service mapping (SCSM) -Mapping to MMS (ISO/IEC 9506 Part 1 and Part 2)
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— DNP3 Distributed Network Protocol (DNP) – V3.0 Basic DocumentSet- DNP V3.0 Data Link Layer- DNP V3.0 Transport Functions- DNP V3.0 Application Layer Specification- DNP V3.0 Data Object Library
— DNP3 Distributed Network Protocol (DNP) – Subset DefinitionsDocument (Level 1, 2, & 3)
— IEEE 1379-2000 IEEE Recommended Practice for Data CommunicationsBetween Remote Terminal Units and Intelligent ElectronicDevices in a Substation (referencing DNP3 and IEC 60870-5-101)
5 WebsitesThe following websites provide further information.
IEC TC 57 related standards
— IEC TC 57 POWER SYSTEM CONTROL AND ASSOCIATED COMMUNICA-TIONS dashboardhttp://www.iec.ch/cgi-bin/procgi.pl/www/iecwww.p?wwwlang=E&wwwprog=TCboard.p&committee=SC&TC=57
— TECHNICAL COMMITTEE N° 57 – General informationhttp://www.iec.ch/cgi-bin/procgi.pl/www/iecwww.p?wwwlang=e&wwwprog=dirdet.p&committee=TC&number=57
— List of publications of all projects of IEC TC 57http://www.iec.ch/cgi-bin/procgi.pl/www/iecwww.p?wwwlang=e&wwwprog=sea1122.p&class=&refno=&search=committee&committee=57&pubno=&part=&se=&header=IEC&pcomm=&dcom=&dclass=&dref=&searchfor=
DNP
— DNP users group: www.dnp.org
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6 Detailed AnalysisThe following tables list the details of the analysis. The yellow fields represent support of a specific feature. The "+" signs indicate atendency of difference in the quantity : "++" means that this solution provides more (functions, comfort, ...) than the other with "+".
Table 1 General issue
Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Application domain Telecontrol(SCADA)
Telecontrol(SCADA), intra-substation and
control-center tosubstation
Protection Telecontrol(SCADA), intra-substation and
control-center tosubstation
Control-center tocontrol-center
Substation andfeeder automation(open for other do-
mains)
Main coverage Application Layer(Services and Pro-
tocol)
Application Layer(Services and Pro-
tocol)
Application Layer(Services and Pro-
tocol) and basicApplication Se-
mantic
Application Layer(Services and Pro-
tocol)
Application Layer(Services and Pro-
tocol) and basicApplication Se-
mantic
Application Se-mantic (models ofdevices and appli-
cations), Substationconfiguration lan-guage, and Appli-
cation Layer(Services and Pro-
tocol)
Standardization IEC Standard(1995)
Amendments (2000,2001)
IEC Standard(2000)
IEC Standard (1997)
Open IndustrySpecification(1993), IEEE
1379 Recom-mended Prac-
tice (2000)
IEC Standard(1997)
Some parts are IECFinal Draft Interna-
tional Standard(FDIS), other areDIS, CDV, CD (as
per 2001-12)
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Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Standardisation Or-ganization
IEC TC 57 WG 03 IEC TC 57 WG 03 IEC TC 57 WG 03 DNP Users Group(took the specifica-tion over in 1993);
IEEE
IEC TC 57 WG 07 IEC TC 57 WG 10,11, and 12
Use in other organiza-tions as base standard
Considered forstandardization byAustralian waterutility industry.
Project 25 of IECTC 88 (Wind Tur-
bine Systems) usesIEC 61850 as base
standard for IEC61400-25
Crucial design ruleused for the develop-ment process of thestandard
Optimize use ofBandwidth and
hardware
Optimize use ofBandwidth and
hardware
Optimize use ofBandwidth and
hardware
Optimize use ofBandwidth and
hardware
Simplify device(data) engineering
and integration
Simplify device(data) engineeringand integration; re-
use models
Further design rules Merge the featuresof earlier proprie-
tary protocols,Push the intelli-gence in the net-work toward theremote device
Merge the featuresof earlier proprie-
tary protocols,Push the intelli-gence in the net-work toward theremote device
Merge the featuresof earlier proprie-tary protocols, Push the intelli-gence in the net-work toward theremote device
Merge the featuresof earlier proprie-tary protocols, Push the intelli-gence in the net-work toward theremote device
Use standardcommunication
protocols.Push the intelli-gence in the net-work toward theremote device
Use standardcommunication
protocols.Push the intelli-gence in the net-work toward theremote device
Crucial Paradigm Exchange of num-bered lists of sim-
ple data points
Exchange of num-bered lists of sim-
ple data points
Exchange of num-bered lists of sim-
ple data points
Exchange of num-bered lists of sim-
ple data points
Exchange ofnamed lists of
simple and com-plex data points
Modeling of appli-cation objects and
exchange of I/Oand Meta data
(Data Management)
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Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Application specific in-formation models
A few (3) applica-tion specific data
types
A few (3) applica-tion specific data
types
Someapplication spe-cific data types
(protection)
Permits vendors tocreate application-
specific exten-sions
Some (10+) appli-cation specificcomplex data
types;Permits vendors tocreate application-
specific exten-sions
Some 100 logicalnode classes with
2000+ dataclasses;
Permits vendors tocreate application-
specific exten-sions
Object-oriented mod-eling
Under develop-ment
Permits object-oriented naming
Supports inheri-tance, encapsula-tion, hierarchical
models, ...
Data Objects and mes-sages independent ofeach other?
No No No Yes Yes Yes
Common applicationlayer / encoding inde-pendent of data defini-tion
+ ++ ++
Implementations avail-able
+++ ++ +++ +++ ++ +
Implementation for em-bedded devices
+++ + ++ +++ + +++
Dominant market Europe (SouthAmerica, Australia,
China)
Europe (SouthAmerica, Australia,
China)
Europe (SouthAmerica, Australia,
China)
North America(South America,Australia, China)
All over All over*
Market penetration(2000)*
+++ + +++ +++ +++
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Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Market penetration(2002)*
++ ++ ++ +++ +++ +
Market penetration(2004)*
++ + + +++ ++ +++
* estimated
Table 2 Process data description
Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
supported data types Fixed Fixed Fixed Fexible Flexible Flexible, easily ex-tendable
Address/Identification Index(commAddr: 8,16
bitsinfoObj: 8/16/24
bits)
Index(commAddr:16 bits
infoObj: 32 bits)
Index(commAddr: 8Bits
function type: 8 bitsinfoObj: 8 bits)
Index(commAddr: 16 bitsPoint Index: 8, 16 or
32 bitsNaming under de-
velopment.
Names32/32 characters
HierarchicalNames
(e.g., AB.E1.Q1/XCBR4.ST.Pos)
Index for reporting
Quality + + + + + +
Timestamp + + + + + +
Cause of transmission + + + + + +
> 1 values in one mes-sage (data groups, datasets)
A few of same typeand same COT
A few of same typeand same COT
A few of same typeand same COT
Several of any type Many of any type Many of any type
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Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Semantic of data(meaning of domain spe-cific data like”time overcurrent”, “PhsA”, “Posi-tion of Circuit Breaker”, ...)
Some(protection)
Some 2000 classes(LN, Data, Data Attr.– for several appli-
cation domains)
Selfdescription of data(for online retrieval)
Some Many Data name, type,functional charac-teristic, reporting
trigger option,deadband, valuerange, ... for any
data class definedand accessible
Open for additionalmodels
Flexible; any newlogical node , data,and common dataclass can be de-
fined for other ap-plication areas
(e.g., wind powerplants)
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Table 3 Operational services
Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Cyclic transmission + + +Permitted, but in-terval cannot be
remotely adjusted+ +
Spontaneous transmis-sion + + + + Flexible Flexible
Read Single Single Single Many Many Many
Write Single Single Single Many Many Many
(device) interrogation + + + + + +
Clock synchronisation + + + +
Control commands + + + + + +
Exchange integratedtotals + + + + +
Remote substitution(online) +
Substitution indication Quality indication Quality indication Quality indication Quality indication Quality indication
Time series data + + + + + Any data(report and logging)
Sequence of events + + + + Status data(report and logging)
Report data values + + + + + Any data(with filter)
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Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Log and retrieve se-lected data values (his-torical) at any time
Any data(with remote filtering
control and othercontrol)
Parameter setting con-trol
Few(measurands)
Few(measurands)
Change pre-defined protectionsetting group only
Change somecommunicationrelated parame-ters; more under
development
Change of somecommunication
related parameterspossible
Flexible(define, change, and
edit)
Substation event Ex-change (GOOSE, ...) +
Sampled value ex-change (for CT and VT) +
File transfer + + + + + +
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Table 4 Selfdescription services
Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Get Directory of AllObjects (Names andtypes of Data of LogicalNodes, ...)
Limited(generic services
only)+
(only flat point lists)
++
(complete informa-tion hierarchy)
Get Definition of opera-tional Objects (Name,Type, range, unit, dead-band for reporting, scale,description, ... of proc-ess data)
+
(deadbands only)
+
(deadbands only)
+
(generic servicesonly)
+
(deadbands only,more under devel-
opment)
++ +++
Get Definition of com-munication service re-lated objects (Report/logcontrol attributes, Controlattributes, Setting groupattributes, ...)
+ + + + ++ +++
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Table 5 Online configuration
Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Define groups of data + + +
Select data for report-ing + + ++
Enable/disable com-muni-cation controlobjects
+ + + ++ +++
Change report-ing/logging behavior + + + ++ +++
Load configuration + + + + +
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Table 6 Offline configuration
Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Complete descriptionof device configuration
Paper documentonly
Paper documentonly
Paper documentonly
Paper documentonly;
Online Documentunder Development
Paper documentonly
XML / XML DTDspecifies the se-mantic of devices,
logical devices, logi-cal nodes, data inthe context of the
real substation (de-scribing the optionalinformation and pri-
vate information)
Support for vendor in-dependent engineeringsystems
Supports the devel-opment of vendorindependent engi-neering tools basedon the comprehen-sive list of classesfor LNs. Data, and
CDC
Location of configura-tion
Configuration ofRTU and/or IED,configuration of da-tabases, and con-figuration of appli-cations
Configuration ofRTU and/or IED,configuration of da-tabases, and con-figuration of appli-cations
Configuration ofRTU and/or IED,configuration of da-tabases, and con-figuration of appli-cations
Configuration ofRTU and/or IED,
configuration of da-tabases, and con-figuration of appli-
cations
Configuration ofRTU and/or IED,
configuration of da-tabases, and con-figuration of appli-
cations
The complete con-figuration is in theIED at any time
consistent; addition-ally in the XML fileof the configuration.
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Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Automatic verificationof online and offlineconfiguration
The complete in-formation modelcan be retrievedonline and auto-matically com-
pared with the off-line configuration
XML file
Table 7 Integration into Applications
Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Data integration Mapping (1) of in-dexed communica-tion objects to ap-plication objects
and (2) applicationobjects to the vari-ables of the apppli-cation database or
programs
Mapping (1) of in-dexed communica-tion objects to ap-plication objects
and (2) applicationobjects to the vari-ables of the apppli-cation database or
programs
Mapping (1) of in-dexed communica-tion objects to ap-plication objects
and (2) applicationobjects to the vari-ables of the apppli-cation database or
programs
Mapping (1) of in-dexed communica-tion objects to ap-plication objects
and (2) applicationobjects to the vari-ables of the apppli-cation database or
programs
Direct mapping ofnamed objects to
the variables of theapplication data-
base or programs.
Direct mapping ofnamed STANDARDobjects to the vari-ables of the appli-cation database or
programs.
Application Program-mers Interface (API) No standard API No standard API No standard API No standard API No standard API No standard API
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Table 8 Architecture and communication stacks
Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Data model independ-ent of services
+ + +
Services independentof communication net-works
+
Communication sys-tems supported
V.24/V.28 orX.24/X.27
TCP/IP overEthernet 802.3 or
X.21
RS 485/Fiber V.24/V.28 orX.24/X.27;
TCP/IP overEthernet 802.3 or
X.21
TCP/IP and OSIover Ethernet802.3 or X.21
TCP/IP and OSIover Ethernet
802.3 or X.21serial
Layering 3 layer 7 layer (TCP/IP) 3 layer (PHL, DLL,AL)
4 layer (serial) or 7layer (TCP/IP or
UDP/IP
7 layerand Object Library
7 layer (TCP/IP andOSI) and LogicalNode (Data andCommon Data)
and object Library;3 layer possible
Mode (Un)balanced Balanced (Un)balanced Balanced Full duplex Full duplex
Routing IP IP if TCP/IP or UDPis supported
IP, OSI NP IP, OSI NP
Transport protocol TCP Pseudo Transportover serial.
Pseudo Transport,encapsulated DataLink Layer, and ei-ther TCP or UDP
over IP
TCP, OSI TP TCP, OSI TP
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Feature 60870-5-101 60870-5-104 60870-5-103 DNP3 60870-6-TASE.2 61850
Addressing Link: 0, 1, or 2 oc-tet
AL: 2 to 5 octets
Stack specific(several address
fields for DLL, Net-work, Transport, ...);
AL: 5 octets fixed
Link: 0, 1, or 2 oc-tet
AL: 3 octets fixed
Source and desti-nation 16-bit overserial. Add stack-specific addressesfor each layer of IP
implementation.TCP/UDP port re-served and fixed.
Stack specific(several address
fields for DLL, Net-work, Transport, ...);application objects
are named (... 64char) or bit mapped
in some cases
Stack specific(several address
fields for DLL, Net-work, Transport, ...);application objects
are named (... 64char) or bit mapped
in some cases
Configuration of com-munication stack
Several attributes Some attributes ofeach layer
Several attributes A few attributes Some attributes ofeach layer
Some attributes ofeach layer
Open for other encod-ing solutions (e.g.,XML)
Under Develop-ment” for DNP3.
+(products are avail-
able that provideHTML and XML
coded messages)
Open for future service(middle ware) systems(HTTP, CORBA, SOAP,...)
+
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7 Summary
The following list gives a brief interpretation of the comparison.
— All solutions provide services to exchange the basic real-time information(e.g., single point status and control, cyclic and spontaneous reports, interro-gation) for SCADA related requirements,
— One provides the real-time information exchange for sampled values and tripcommands (61850).
— Most have mainly fixed functionality (101, 103, 104, DNP, TASE.2), onesupports broad applicability covering data modeling, self-descriptionservices, configuration service, and advanced communication modelsand services (61850),
— Some are available in many products and applied all over (101, 103, DNP,TASE.2), products are available (104), or under development (61850),
— Some use many main-road technologies (61850, TASE.2, 104/DNP partly)or use proven (restricted) solutions (101, 103, 104/DNP partly),
— DNP3 and IEC 60870-5-101/104 have basically the same functionality.
— All solutions provide a first level of Data Acquisition Interoperability
— One (61850) will probably become the preferred IEC solution within the fu-ture IEC TC 57 seamless Telecontrol Communication Architecture (sTCA),applications of the other solutions will migrate to the use of 61850 step bystep; (TC 57 SPAG decision with regard to the use of 61850 as preferred ex-pected in spring 2002).
— One (61850) has the potential to be used as an integrated Information Man-agement in almost all utility applications domains (electric, distributed electric,gas, water), providing the user with consistent Knowledge of the Systemon-line.
— One (61850) allows for a high level Application Interoperability providingapplication domain specific information models (semantic of data) rather thaninteroperable data exchange services only.
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Additional information
1. 'Use of the standard IEC 61850 outside the areas of Electrical Utilities'www.scc-online.de/download/IEC_TC57/UCA-IEC61850_in-non-Utility-areas.zip
2. Client/Server Demo Software and Tutorial for IEC 61850 / IEC 61400-25 /UCA™ / MMS (with Web / XML support)www.nettedautomation.com/solutions/demo/20020114/index.html
3. Version 1 of this comparison (without DNP3) – 2001-08-28www.nettedautomation.com/news/n_44.html
I would appreciate receiving your comments.
Best Regards,
Karlheinz Schwarz, M. Sc.Member of IEC TC 57 WG 11 and TC 88 PT 25Editor of IEC 61850-7-1 (7-2 ) and IEC 61400-25Schwarz Consulting Company, SCCIm Eichbaeumle 108D-76139 KarlsruheGermany
Phone +49-721-684844Fax +49-721-679387
Email [email protected] URL www.scc-online.de URL www.nettedautomation.comURL www.dispowergen.com