IEC 61850

Short Tutorial
Klaus-Peter Brand

klaus-peter.brand@ch.abb.com
 Lecturer

Scope
Market Klaus-Peter Brand
requirements
ABB Switzerland Ltd
The standard ABB University Switzerland & ABB Power
structure
Technology Systems (Utility Automation)
Acceptance Member of TC 57 WG10
Approach Editor of IEC 61850-5
Logical Nodes
Co-editor of IEC 61850-7-4
and objects Co-editor of IEC 61850-10
Hierarchical
Member of Group of Experts handling amendments,
data model updates and extensions of IEC 61850
Services Liaison officer CIGRE SC B5 – IEC TC57
SCL klaus-peter.brand@ch.abb.com
Outlook

IEC 61850 Short Tutorial March2005 / Page 2

 Scope and SA structure

Scope IEC 61850 means Serial Communication for all functions

Market both between Station/Bay Level and Bay/Process Level
requirements
Station HMI Station Station
The standard level computer gateway
structure

Acceptance
Station
Approach bus
Logical Nodes Bay
and objects Control Protection Protection Control Protection
level & Control
Hierarchical
Process
data model Cu wires
bus
Services Process Interface Process Interface Process Interface
Process
SCL
level Switchgear/Switchyard
Outlook

IEC 61850 Short Tutorial March2005 / Page 3

 Situation before IEC 61850

Scope
Market
requirements
Station HM I Central Station
The standard level Gateway
Functions
structure

Acceptance

Approach

Logical Nodes Bay

and objects Protection Protection Protection Protection Protection
level 1 2 & Control 1 2
Hierarchical
data model MVB,CAN others
Services Processinterface Processinterface Processinterface
Process
SCL
level
Outlook

IEC 61850 Short Tutorial March2005 / Page 4

 Market requirement

Scope
Market
requirements

The standard
structure Because of the
Acceptance • global, deregulated market
Approach • transnational business of utilities
Logical Nodes • international business of providers
and objects

Hierarchical
data model one and only one global standard
Services for communication in substations
SCL and beyond is needed
Outlook

IEC 61850 Short Tutorial March2005 / Page 5

 Requirements and meaning

Scope
Interoperability The ability for IED’s from one or several
Market
requirements manufacturer to exchange information and use
the information for the their own functions.
The standard
structure

Acceptance Free configuration The standard shall support different philosophies

Approach
and allow a free allocation of functions e.g. it must
work equally well for centralized (RTU like) or
Logical Nodes decentralized (SCS like) systems.
and objects

Hierarchical Long term stability The standard shall be future proof, i.e.
data model it must be able to follow the progress in
Services communication technology as well as
evolving system requirements.
SCL
Outlook

IEC 61850 Short Tutorial March2005 / Page 6

 The response: IEC 61850 - structure (1)

Scope
IEC 61850-x (x = part number)
Market
requirements
System Aspects Configuration
The standard
Part 1: Introduction and Part 6: Configuration Language
structure
Overview for electrical
Acceptance Substation IEDs
Part 2: Glossary
Approach
Part 3: General Requirements
Logical Nodes Part 4: System and Project
and objects Management IEC
is 618
Hierarchical Part 5: Comm. Requirement r 5
data model for Functions and for ead 0
Device Models us y
Services
e

SCL
Outlook

IEC 61850 Short Tutorial March2005 / Page 7

 The response: IEC 61850 - structure (2)

Scope
IEC 61850-x (x = part number)
Market
requirements
Abstract Communication Services Mapping to real Comm. Networks
The standard (SCSM)
Part 7-1: Principles and Models
structure
Part 7-2: Abstract Communication Part 8-1: Mapping to MMS and
Services (ACSI) to ISO/IEC 8802-3
Acceptance
Data Models Part 9-1: Sampled Values over
Approach Serial Unidirectional
Part 7-3: Common Data Classes Multi-drop Point-to-Point link
Logical Nodes
and objects Part 9-2: Sampled values
Part 7-4: Compatible Logical Node
Classes and Data Classes over ISO 8802-3
Hierarchical
data model Testing

8 50 Part 10: Conformance Testing

Services 1
6 y
SCL IEC read
is use
Outlook for
IEC 61850 Short Tutorial March2005 / Page 8
 Acceptance by Suppliers: see exhibition at Cigre exhibition Paris 2004

Scope Booth of IEC 61850 Users Group „UCA International“

Market
requirements

The standard
structure

Acceptance

Approach

Logical Nodes
and objects

Hierarchical
data model

Services

SCL
Outlook

IEC 61850 Short Tutorial March2005 / Page 9

 Acceptance by Suppliers: participation at the UCA International booth

Scope
Market
requirements

The standard
structure

Acceptance

Approach

Logical Nodes
and objects

Hierarchical
data model

Services

SCL
Outlook

IEC 61850 Short Tutorial March2005 / Page 10

 Acceptance by Customers: Pilot projects

Scope
Market
Pilot projects have been started at
requirements the end of 2004
The standard
structure

Acceptance
They are not part of the
Approach Tutorial
Logical Nodes but will be reported
and objects
in the
Hierarchical
data model Workshops
Services or in the
SCL Manufacturers’ Forum
Outlook

IEC 61850 Short Tutorial March2005 / Page 11

 Approach and meaning

Scope Problem for Solution for

standardization approach standardization approach
Market
requirements Application
Slow APPLICATION
Domain switching devices DATA MODEL
The standard Substation protection & control Objects
structure commands, events, Service
alarms,
Acceptance …

Approach

Logical Nodes
and objects
COMMUNICATION ISO/OSI 7
Hierarchical messages, 6
data model seven
telegrams, frames 5
layer
on the wire 4
Services …
stack 3
Communication 2
SCL Fast Technology 1

Outlook

IEC 61850 Short Tutorial March2005 / Page 12

 Introduction of Logical nodes

Scope Communication relations in a

Market Substation Automation System
requirements
Information is exchanged between all devices (IED)
The standard
structure which comprise the system
Acceptance More precisely, data are exchanged between the
Approach functions and sub-functions residing in the devices
Logical Nodes The smallest part of the function that exchanges data
and objects
is called Logical Node (LN) in IEC 61850. The LN
Hierarchical performs some operations for the overall function
data model

Services
IED IED
SCL LN LN

Outlook

IEC 61850 Short Tutorial March2005 / Page 13

 Logical Nodes in the Language of Substation Engineers
Control
Scope Example GIS Q0/CSWI
Market Q8/CSWI
requirements Q9/CSWI
Bay-HMI
The standard IHMI
structure Earthing Switch
Q8_L1/XSWI
Acceptance Gas density mon.
Q8_L1/SIMG
Approach
Secondary
Logical Nodes Isolator
and objects Q9_L1/XSWI technology
Gas density mon.
Hierarchical Q9_L1/SIMG
data model
Circuit Breaker
Services Distance
Q0_L1/XCBR
Gas density mon. Protection
SCL Primary technology
Q0_L1/SIMG PDIS
Outlook

IEC 61850 Short Tutorial March2005 / Page 14

 Logical Node Groups (First letter listed)

Scope L System LN (2) M Metering and measurement (8)

Market P Protection (28) S Sensor and monitoring (4)
requirements R Protection related (10) X Switchgear (2)
The standard C Control (5) T Instrument transformers (2)
structure
G Generic (3) Y Power transformers (4)
Acceptance I Interfacing and archiving (4) Z Further power system
A Automatic control (4) equipment (15)
Approach

Logical Nodes
and objects
Examples
Hierarchical PDIF: Differential protection CSWI: Switch controller
data model RBRF: Breaker failure MMXU: Measurement unit
Services XCBR: Circuit breaker YPTR: Power transformer
SCL
Outlook

IEC 61850 Short Tutorial March2005 / Page 15

 Data model: Hierarchy

Physical Device (IED) Bay Unit

Scope
defined as Server
Market
requirements ↑ Implementation
The standard Logical Device (LD) Control
structure
↑ Grouping
Acceptance
Logical
Logical Node
Node (LN)
(LN) CSWI Switch Control
Approach
Data ↓
Logical Nodes
and objects Data (Object) Position

Hierarchical Properties ↓
data model
Attribute Control Value
Services off/on
Value Status Value
SCL intermediate/off/on/bad

Outlook

IEC 61850 Short Tutorial March2005 / Page 16

 Data model: Hierarchical set of objects

Scope
Data container with related data
Market Example: Modeling of a combined Common
requirements
Control-Protection device LLN0
Name plate
The standard
“Vendor etc.”
structure
Common LLN0
Physical Device (Server)

Acceptance Control
Switch Control
Approach Control LLN0
Position
Logical Nodes CSWI Pos ctlVal stVal Control Value
and objects Status Value

Hierarchical LLN0
Protection Protection
data model
PTOC Overcurrent
Services Str Op Start/Pick-up
Operate/Trip
SCL
Outlook
See IEC 61850-7-1,2,3,4
IEC 61850 Short Tutorial March2005 / Page 17
 Benefits of modeling relationships between LNs

Scope Device Example: Station Workplace

Market IHMI
requirements (Human Machine IF)
The standard
structure

Acceptance
Device Example: Combined Protection and Control Unit
CSWI PDIS
Approach (Switch Controller) (Distance Protection)

Logical Nodes
and objects
TVTR
Hierarchical
XCBR (Voltage Transformer)
data model
(Circuit Breaker)
Services TCTR
(Current Transformer)
SCL Device Example:
Circuit Breaker Device Example: Combisensor
Outlook

IEC 61850 Short Tutorial March2005 / Page 18

 Example for Logical Node: LN XCBR out of IEC 61850-7-4

Scope
!
Market
requirements ! "# # ! $
%&
" #$ "
The standard % & ' ( ( ( ( ) "
' !
structure * + ,(& -
$% + ,(& & -
Acceptance -& -& ( "

Approach % ' ' & "

./-& % . / & "

Logical Nodes ./ % . / "
and objects " % -
!(
Hierarchical ( '01 .1 ( ' 0 & ) -
data model ) "#
.-& & ( / & & # "
Services
%-2 & % - 2 3 ' & # -

SCL " +-& & ( / & & #' (# -

Outlook

IEC 61850 Short Tutorial March2005 / Page 19

 Example for Common Data Class DPC

Scope off/on
Attribute Attribute Type
Market Name
requirements Control and ctlVal BOOLEAN
intermediate/off/on/bad
status operTm TimeStamp
The standard
structure
stVal CODED ENUM
q Quality
Acceptance t TimeStamp
Approach pulseConfig PulseConfig
Configuration ctlModel CtlModels
Logical Nodes and description sboTimeout
and objects INT32U
sboClass SboClasses
Hierarchical d Visible String255
data model
subEna BOOLEAN
Services Substitution subVal CODED ENUM
SCL subQ Quality
Outlook
subID Visible String64

IEC 61850 Short Tutorial March2005 / Page 20

 Example for Logical Node: LN PDIS out of IEC 61850-7-4
'"
)
Scope
!
4
Market
requirements ! "# # ! $
%&
" #$ 4 "
The standard -& 1 1 & ( -
structure ) "#
0$ "
Acceptance -& 05 -& 5 "
)
%1 06 % 1 " -
Approach
% 06 % 7( -
6 06 6 ( 7( -
Logical Nodes
$" 6 $ " -
and objects %1 06 % 1 -
- 06 - -
Hierarchical %- 06 % - -
data model 1 06 1 3 -
0 06 0 -
Services

SCL more …
Outlook

IEC 61850 Short Tutorial March2005 / Page 21

 Common data classes (CDC)

Scope Status information (7) Status settings (2)

Market Analogue settings (2)
requirements Measured information (9)

Controllable status (5) Description information (3)

The standard
structure
Controllable analogue (1)
Acceptance

Approach

Logical Nodes
and objects Examples
SPS: Single point status DPC: Double point control
Hierarchical SPG: single point setting
ACT: Protection activation
data model
information DPL: Device nameplate
Services MV: Measured value
SCL WYE: 3 Phase measured value
Outlook

IEC 61850 Short Tutorial March2005 / Page 22

 Services

Scope Standardized data access and transfer (Services)

Market
requirements read a value / attribute
write configuration attributes
The standard
structure
control a device (direct operate / select before operate)
Acceptance event oriented communication with reporting
local storage of time-stamped events in a log
Approach
get directory information
Logical Nodes file transfer for e.g.
and objects - parameter and software download
- upload from monitoring information like travel curves or history of
Hierarchical
gas density values
data model

Services Transfer of generic object oriented system events (GOOSE)

SCL Transfer of sampled analog values (SAV)

Outlook

IEC 61850 Short Tutorial March2005 / Page 23

 IEC 61850: Details for Communication services
SA specific data model Model according to state-of-the-art SA technology
Scope evolves slowly
Market Communication technology Data Model (Objects,Services)
requirements changes quickly

The standard Splitting of SA specific

structure data model from Client Server Sampled
communication technology GOOSE*
Communication Values
Acceptance
Mapping
Approach Abstract
Communication
Services
Logical Nodes Interface (ACSI)

and objects MMS Real time

Stack
Interface
Communication
Hierarchical TCP
ISO/OSI – Stack
data model Hierarchical set of IP
Rules how information is coded for
transmission Ethernet Link Layer
Services According to state-of-the art
communication technology Ethernet Physical Layer with Priority tagging (100 Mbit/s)
SCL
* Generic Object Oriented Stack selection according to the state-of-the-art
Outlook Substation Event Communication technology

IEC 61850 Short Tutorial March2005 / Page 24

 Client-server communication and reporting

Client-server communication
Scope
using full seven layer stack
Market confirmed transmission layer
requirements very reliable
relatively time consuming.
The standard
structure Therefore, the client-server communication is not suited for time-critical
data transmission but very well for the communication with an operator
Acceptance having a response time of the order of 1 s.

Approach The server

is the source of all data for the client
Logical Nodes
and objects The client
asks the server for information.
Hierarchical changes by parameter setting the behavior of the server
data model
issues commands via the server e.g. to switchgear
Services configures at the server conditions which allow the server to send a
report automatically to the client (report control block)
SCL The content of the report is defined by a data set. In contrast to master-slave
Outlook mulitiple client-server links are possible.

IEC 61850 Short Tutorial March2005 / Page 25

 Time critical communication with GOOSE

No data change Problem for real-time data:

Scope
- No time for acknowledgement
Market - No time for repetition after loss detected
requirements GOOSE messages
(content defined by data set) are repeated with maximum interval Tmax
The standard
structure

Acceptance
Tmax = 1024 ms Tmax = 1024 ms time
Approach
Data change GOOSE messages starts immediately with the changed
Logical Nodes values in some short repetition intervals (Tmin), then the
and objects interval will be increase (fast or slowly) to Tmax

Hierarchical
b
data model

Services
Tmin = 2 ms time
SCL Tmax = 1024 ms
Outlook
Tmax = 1024 ms Tmax = 1024 ms
IEC 61850 Short Tutorial March2005 / Page 26
 Time critical data flow with SV (sample values)

Problem for real-time data:

Scope
- No time for acknowledgement
Market - No time for repetition after loss detected
requirements
Benefit for samples:
The standard Some few samples may be lost
structure without impact on the function to be performed
Acceptance

Approach Sampled values (SV) messages are very similar to GOOSE messages:

Logical Nodes SV messages are defined with help of data sets;

and objects the start event is a continuous clocks pulse

Hierarchical The problem is the high synchronicity requested for phasors (about 1 µs);
data model this problem has to be solved by time pulses for the time being.

Services An extensions for time synchronization over the bus according to IEEE 1588
is not yet included but in preparation for IEC 61850
SCL
Outlook

IEC 61850 Short Tutorial March2005 / Page 27

 Substation Configuration description Language (SCL)

Scope
Formal description of device and system structure
Market
requirements
To provide interoperability a formal description of the
The standard Substation Automation System with all communication links is
structure needed
Acceptance
All IED capabilities have to be described formally in an
Approach unambiguous way
Logical Nodes
and objects All communication services applicable have to be described
formally in an unambiguous way
Hierarchical
data model
The relationship between the switchgear (single line) and
Services
the data of the substation automation system have to be
SCL described formally in an unambiguous way
Outlook

IEC 61850 Short Tutorial March2005 / Page 28

 Topics of SCL

Scope HMI GW
Market
requirements
Description of Single line diagram
The standard
structure Allocation to Single line diagram

Acceptance Access points for LAN connection

Approach What inputs, e.g. GOOSE messages belong to an IED? Input section !

Logical Nodes Data sets and control blocks for report and GOOSE messages
and objects Instantiable types of
LNs (LN Type), Data objects (DO types), Data attributes (DA types)
Hierarchical
data model
Data model (server side) with services: IED capability description
Services

SCL BU 1 BU 2 BU 3 BU 4
Outlook

IEC 61850 Short Tutorial March2005 / Page 29

 SCL: Formal description of device and system structure

Scope
For the formal description is provided by the
Market
requirements Substation Configuration description Language (SCL)

The standard
structure
based on XML
defined in part 6 of the standard (IEC 61850-6)
Acceptance usable for
Approach IED Capability Description (ICD) files
System Configuration Description (SCD) file
Logical Nodes
and objects System functional specification (SSD)
and more
Hierarchical
data model
The engineering information is exchangeable
Services
between tools !!!
SCL
Outlook
See IEC 61850-6
IEC 61850 Short Tutorial March2005 / Page 30
 The Engineering Process with SCL

SCD file
Scope Device
part per
Market Device (IED) IED specific
requirements tool
Device Selection
The standard IED Capability De-
structure scription (ICD) file

Acceptance SCL files

System
Approach configurator
System
Logical Nodes Configuration
and objects Description (SCD)
System specification
description (SSD) file file
Hierarchical
data model System
Single Feeder
Documentation
Services Line Block
files
Diagram Diagram
SCL (S/S (function
spec) spec)
Outlook

IEC 61850 Short Tutorial March2005 / Page 31

 Design example

Scope Ethernet HMI GW

Market Ring
requirements

The standard
structure
Ethernet
Acceptance
Switch
Approach

Logical Nodes
and objects

Hierarchical
data model

Services
BU 1 BU 2 BU 3 BU 4
SCL
Outlook Bay Control and/or
Protection Unit
IEC 61850 Short Tutorial March2005 / Page 32
 IEC 61850: What is standardized and what not ?

Scope
Standardized
Market
requirements
Data model with LN, DO, Attributes
The standard Services
structure Configuration Language (SCL)
Acceptance
ICD file (requested) and other SCL based files

Approach
Not standardized
Logical Nodes
and objects
LD and high plant identification
Hierarchical Functions
data model Allocation of functions to IEDs
Services SA concepts and architectures
Redundancy
SCL Tools and engineering process
Outlook

IEC 61850 Short Tutorial March2005 / Page 33

 Future
Activities
Scope
Maintenance of IEC 61850 within substations
Market
requirements Work started to use use IEC 61850 also outside the substation, i.e.
for wind power,
The standard for hydro power,
structure
for distributed energy resources (DER)
Acceptance The feasibility of IEC 61850 for the link to the NCC has been
Approach proven, a harmonization between the data model of IEC 61850
and the CIM model on Network Level is in progress
Logical Nodes
and objects New work items to use IEC 61850 for line protection
(teleprotection) are in preparation.
Hierarchical
data model The IEC TC57 WG10 takes care to the common data model
Services The user group UCA International promotes the standard and
tries to support all users.
SCL
Outlook
The goal is a seamless communication architecture for utilities

IEC 61850 Short Tutorial March2005 / Page 34