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- Herausgeber: John Wiley & Sons
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
Substation Automation Systems: Design and Implementation aims to close the gap created by fast changing technologies impacting on a series of legacy principles related to how substation secondary systems are conceived and implemented. It is intended to help those who have to define and implement SAS, whilst also conforming to the current industry best practice standards.
Key features:
- Project-oriented approach to all practical aspects of SAS design and project development.
- Uniquely focusses on the rapidly changing control aspect of substation design, using novel communication technologies and IEDs (Intelligent Electronic Devices).
- Covers the complete chain of SAS components and related equipment instead of purely concentrating on intelligent electronic devices and communication networks.
- Discusses control and monitoring facilities for auxiliary power systems.
- Contributes significantly to the understanding of the standard IEC 61850, which is viewed as a “black box” for a significant number of professionals around the world.
- Explains standard IEC 61850 – Communication networks and systems for power utility automation – to support all new systems networked to perform control, monitoring, automation, metering and protection functions.
Written for practical application, this book is a valuable resource for professionals operating within different SAS project stages including the: specification process; contracting process; design and engineering process; integration process; testing process and the operation and maintenance process.
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Veröffentlichungsjahr: 2015
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Table of Contents
Cover
Title Page
Preface
Acknowledgments
List of Abbreviations
1 Historical Evolution of Substation Automation Systems (SASs)
1.1 Emerging Communication Technologies
1.2 Intelligent Electronic Devices (IEDs)
1.3 Networking Media
1.4 Communication Standards
Further Reading
2 Main Functions of Substation Automation Systems
2.1 Control Function
2.2 Monitoring Function
2.3 Alarming Function
2.4 Measurement Function
2.5 Setting and Monitoring of Protective Relays
2.6 Control and Monitoring of the Auxiliary Power System
2.7 Voltage Regulation
Further Reading
3 Impact of the IEC 61850 Standard on SAS Projects
3.1 Impact on System Implementation Philosophy
3.2 Impact on User Specification
3.3 Impact on the Overall Procurement Process
3.4 Impact on the Engineering Process
3.5 Impact on Project Execution
3.6 Impact on Utility Global Strategies
3.7 The Contents of the Standard
3.8 Dealing with the Standard
Further Reading
4 Switchyard Level, Equipment and Interfaces
4.1 Primary Equipment
4.2 Medium and Low Voltage Components
4.3 Electrical Connections between Primary Equipment
4.4 Substation Physical Layout
4.5 Control Requirements at Switchyard Level
Further Reading
5 Bay Level: Components and Incident Factors
5.1 Environmental and Operational Factors
5.2 Insulation Considerations in the Secondary System
5.3 Switchyard Control Rooms
5.4 Attributes of Control Cubicles
5.5 The Bay Controller (BC)
5.6 Other Bay Level Components
5.7 Process Bus
Further Reading
6 Station Level: Facilities and Functions
6.1 Main Control House
6.2 Station Controller
6.3 Human Machine Interface HMI
6.4 External Alarming
6.5 Time Synchronization Facility
6.6 Protocol Conversion Task
6.7 Station Bus
6.8 Station LAN
Further Reading
7 System Functionalities
7.1 Control Function
7.2 Monitoring Function
7.3 Protection Function
7.4 Measuring Function
7.5 Metering Function
7.6 Report Generation Function
7.7 Device Parameterization Function
Further Reading
8 System Inputs and Outputs
8.1 Signals Associated with Primary Equipment
8.2 Signals Associated with the Auxiliary Power System
8.3 Signals Associated with Collateral Systems
9 System Engineering
9.1 Overall System Engineering
9.2 Bay Level Engineering
9.3 Station Level Engineering
9.4 Functionalities Engineering
9.5 Auxiliary Power System Engineering
9.6 Project Drawings List
9.7 The SAS Engineering Process from the Standard IEC 61850 Perspective
Further Reading
10 Communication with the Remote Control Center
10.1 Communication Pathway
10.2 Brief on Digital Communication
10.3 Overview of the Distributed Network Protocol (DNP3)
Further Reading
11 System Attributes
11.1 System Concept
11.2 Network Topology
11.3 Redundancy Options
11.4 Quality Attributes
11.5 Provisions for Extendibility in Future
11.6 Cyber-Security Considerations
11.7 SAS Performance Requirements
Further Reading
12 Tests on SAS Components
12.1 Type Tests
12.2 Acceptance Tests
12.3 Tests for Checking the Compliance with the Standard IEC 61850
Further Reading
13 Factory Acceptance Tests
13.1 Test Arrangement
13.2 System Simulator
13.3 Hardware Description
13.4 Software Identification
13.5 Test Instruments
13.6 Documentation to be Available
13.7 Checking System Features
13.8 Planned Testing Program for FAT
13.9 Nonstructured FATs
13.10 After FATs
Further Reading
14 Commissioning Process
14.1 Hardware Description
14.2 Software Identification
14.3 Test Instruments
14.4 Required Documentation
14.5 Engineering Tools
14.6 Spare Parts
14.7 Planned Commissioning Tests
14.8 Nonstructured Commissioning Tests
14.9 List of Pending Points
14.10 Re-Commissioning
Further Reading
15 Training Strategies for Power Utilities
15.1 Project-Related Training
15.2 Corporate Training
Further Reading
16 Planning and Development of SAS Projects
16.1 System Specification
16.2 Contracting Process
16.3 Definition of the Definitive Solution
16.4 Design and Engineering
16.5 System Integration
16.6 Factory Acceptance Tests
16.7 Site Installation
16.8 Commissioning Process
16.9 Project Management
16.10 Security Issues
16.11 Documentation and Change Control
Further Reading
17 Quality Managementfor SAS Projects
17.1 Looking for Quality in Component Capabilities and Manufacturing
17.2 Looking for Quality during the Engineering Stage
17.3 Looking for Quality in the Cubicle Assembly Stage
17.4 Looking for Quality during FAT
17.5 Looking for Quality during Installation and Commissioning
17.6 Use of Appropriate Device Documentation
Further Reading
18 SAS Engineering Process According to Standard IEC 61850
18.1 SCL Files
18.2 Engineering Tools
18.3 Engineering Process
Further Reading
19 Future Technological Trends
19.1 Toward the Full Digital Substation
19.2 Looking for New Testing Strategies on SAS Schemes
19.3 Wide Area Control and Monitoring Based on the IEC/TR 61850–90–5
19.4 Integration of IEC 61850 Principles into Innovative Smart Grid Solutions
Further Reading
Appendix A Samples of Equipment and System Signal Lists
A.1 Signals List Related to Circuit Breakers (Each One)
A.2 Signals List Related to Collateral Devices
A.3 Signals List Related to the Auxiliary Power System
A.4 Signals List Related to the SAS Itself
Appendix B Project Drawing List: Titles and Contents
B.1 General Interest Drawings
B.2 Electromechanical Drawings (High Voltage Equipment and Control Facilities)
B.3 Electromechanical Drawings (Control, Protection, Measurement and Communications)
B.4 Electromechanical Drawings (Auxiliary Power System)
Appendix C Essential Tips Related to Networking Technology
C.1 Computer Network
C.2 Network Topology
C.3 Network Structure
C.4 Communication Protocols
C.5 Geographical Scale of Network
C.6 Internetwork
C.7 Network Structure
C.8 Communication System
C.9 Object-Oriented Programming
C.10 Programming Tool or Software Development Tool
Index
End User License Agreement
List of Tables
Chapter 03
Table 3.1 Existing parts of the IEC 61850 Standard
Table 3.2 Content of the Standard
Table 3.3 Suggested priority reading in the Standard
Chapter 04
Table 4.1 Switchyard control requirements
Chapter 07
Table 7.1 Example of matrix for voltage synchronization criteria
Chapter 08
Table 8.1 Signals associated with circuit breakers
Table 8.2 Signals associated with disconnectors
Table 8.3 Signals associated with earthing switches
Table 8.4 Signals associated with voltage transformers
Table 8.5 Signals associated with current transformers
Table 8.6 Signals associated with power transformers
Table 8.7 Signals associated with MV circuit breakers
Table 8.8 Signals associated with MV distribution transformers
Table 8.9 Signals associated with LV circuit breakers
Table 8.10 Signals associated with Distribution Center “A”
Table 8.11 Signals associated with Distribution Center “B”
Table 8.12 Signals associated with AC distribution cubicles for essential loads
Table 8.13 Signals associated with the diesel generator
Table 8.14 Signals associated with AC distribution cubicles for nonessential loads
Table 8.15 Signals associated with DC transfer switches
Table 8.16 Signals associated with DC distribution cubicles
Table 8.17 Signals associated with batteries and chargers
Table 8.18 Signals associated with collateral systems
Chapter 09
Table 9.1 Example of fixing switchgear position/condition indication
Table 9.2 Example of form for fixing colors for primary circuits
Table 9.3 Example of form for fixing attributes of process objects
Table 9.4 Example of a form for fixing analogue values attributes
Table 9.5 Example of format for fixing alarm attributes
Table 9.6 Example of the bay controller signal list
Table 9.7 Example of the BC auxiliary system signal list
Table 9.8 Example of the station controller signal list
Table 9.9 Example of the remote control level signal list
Table 9.10 Example of a point to point signals list
Table 9.11 Simplified model of a process database
Chapter 11
Table 11.1 Comparison between several network arrangements
Table 11.2 Summary of component reliability figures
Chapter 12
Table 12.1 Basic characteristics tests for bay controllers
Table 12.2 Functional tests for bay controllers
Chapter 13
Table 13.1 Examples of nonstructured FATs
Chapter 14
Table 14.1 Examples of nonstructured commissioning tests
Chapter 17
Table 17.1 Model of inspection and test plan ITP
Table 17.2 Nonconformities detected in cubicle assembly stage
Table 17.3 Non conformities detected in FAT
Table 17.4 Nonconformities detected in the commissioning process
Table 17.5 Set of documents referring to IEDs
List of Illustrations
Chapter 01
Figure 1.1 View of a 765 kV electric substation.
Figure 1.2 Old mimic control board.
Figure 1.3 Substation primary arrangement shown outside control cubicles.
Figure 1.4 Flag relay.
Figure 1.5 Old cabling channels.
Figure 1.6 Control cubicles of a modern SAS.
Figure 1.7 Operation desk of a modern SAS.
Chapter 02
Figure 2.1 View of a 400 kV circuit breaker.
Figure 2.2 View of a 400 kV disconnector (in the closed position).
Figure 2.3 View of a 115 kV earthing switch.
Figure 2.4 View of a 765 kV power transformer.
Figure 2.5 View of a distribution cubicle.
Figure 2.6 View of a battery room.
Figure 2.7 Simplified model of a SAS
Chapter 04
Figure 4.1 View of a 765 kV substation switchyard.
Figure 4.2 Vertical style 400 kV circuit breaker.
Figure 4.3 400 kV Disconnector in an open position.
Figure 4.4 Capacitive voltage transformers stored as spare parts.
Figure 4.5 Current transformers stored as spare parts.
Figure 4.6 View of a CT secondary terminal box.
Figure 4.7 View of a single-phase 765 kV power transformer.
Figure 4.8 Power transformer temperature indicators.
Figure 4.9 Medium voltage auxiliary power transformer.
Figure 4.10 A bay junction box.
Figure 4.11 Example of a substation primary arrangement
Figure 4.12 A 765 kV line entrance.
Figure 4.13 A 765 kV bay.
Figure 4.14 Example of a substation physical layout
Figure 4.15 Set of key interlocking devices.
Chapter 05
Figure 5.1 Substation provided with overhead shielding wires.
Figure 5.2 Power transformers protected by surge arresters.
Figure 5.3 View of an already installed earth conductor.
Figure 5.4 Protective bonding conductors (right side).
Figure 5.5 View of a switchyard/local control room.
Figure 5.6 Mesh for shielding of switchyard control rooms
Figure 5.7 View of a control cubicle.
Chapter 06
Figure 6.1 View of a main control house.
Figure 6.2 View of a control room.
Figure 6.3 View of a HMI.
Figure 6.4 Example of the start-up screen
Figure 6.5 Example of main box screen
Figure 6.6 Example of an user administrator screen
Figure 6.7 Example of primary voltage switchyard screen
Figure 6.8 Example of a SAS scheme screen
Figure 6.9 Example of an event list screen
Figure 6.10 Example of the alarm list screen
Chapter 07
Figure 7.1 Control concepts
Figure 7.2 Examples of symbols to represent primary switchgear
Chapter 09
Figure 9.1 Example of SAS solution evolution
Chapter 10
Figure 10.1 Communication pathway with the remote control center
Figure 10.2 Structure of the OSI Reference Model
Figure 10.3 Structure of the EPA model
Chapter 11
Figure 11.1 Single star topology
Figure 11.2 Double star topology
Figure 11.3 Single ring topology
Figure 11.4 Crossover topology
Figure 11.5 Hypothetical SAS topology for availability calculation
Chapter 17
Figure 17.1 Control cubicle ready for inspection.
Chapter 18
Figure 18.1 Simplified flow diagram of engineering process
Guide
Cover
Table of Contents
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SUBSTATION AUTOMATION SYSTEMS
DESIGN AND IMPLEMENTATION
Evelio Padilla
Eleunion C.A., Caracas, Venezuela
This edition first published 2016© 2016 John Wiley & Sons, Ltd.
Registered OfficeJohn Wiley & Sons, Ltd., The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, United Kingdom
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Library of Congress Cataloging-in-Publication Data
Padilla, Evelio.Substation automation systems : design and implementation / Evelio Padilla, Eleunion, Venezuela. pages cm Includes bibliographical references and index.
ISBN 978-1-118-98720-9 (cloth)1. Electric substations–Automatic control. I. Title. TK1751.P33 2016 621.31′26–dc23 2015021965
A catalogue record for this book is available from the British Library.
Preface
A number of technological changes have occurred in the substation environment over the last 30 years. Surge arresters built with metal oxide discs, circuit breakers isolated with SF6 gas, numerical protective relays and other novel products that appeared early in the 1980s, were quickly adopted without significant impact on substation design. A few years after, however, the incursion of digital technology caused a “jerk” in the field of substation secondary systems. While young system engineers with a limited knowledge in substation-related concepts have become engaged in development of the engineering process Substation Automation Systems (SASs) from the side of device manufacturers, experienced utilities personnel had to (and in some cases still need to) face up to many disconcerting and complex scenarios characterized by an unusual lexicon and a lot of abstract resources that are now being applied to define and implement control and monitoring functionalities in their substations.
This book intends to help both professional groups accomplish their responsibilities by giving them guidelines with respect to the scope and functions of SASs based on current technology, including requirements from Standard IEC 61850, as well useful details for dealing with various stages needed for SAS project development.
The material is organized into 19 chapters; Chapter 1 providing a brief review on how SAS has recently evolved, Chapter 2 outlines the purpose of the SAS as an essential part of the substation, in Chapter 3 the effects of Standard IEC 61850 on different stages of SAS projects are presented, Chapter 4 illustrates constructive and functional features of equipment that make up the primary power circuit, Chapter 5 introduces the characteristics of Intelligent Electronic Devices (IEDs) used for control and monitoring and describe briefly certain phenomenon able to affect in detrimental way the physical/functional integrity of such devices, Chapter 6 provides an overview of how the features and functions of devices installed into the main control house are used for controlling and monitoring the substation as a whole, Chapter 7 contains different SAS functionalities including switching commands and constraints like interlocking and blocking conditions, Chapter 8 shows the set of signals coming from different substation components that need to be managed by the SAS, Chapter 9 suggests how the SAS ought to be engineered, Chapter 10 covers the theory and practical principles that support a typical implementation needed for the substation control and monitoring from a remote master station, Chapter 11 describes a lot of items that may characterize the SAS structure including options for the network topology further to quality requirements and cyber-security considerations, Chapter 12 contains recommendations regarding the tests to carry out on SAS components, Chapter 13 may serve as a baseline for programming and checking results of Factory Acceptance Tests (FATs) performed on representative SAS segments, Chapter 14 covers site testing scope and strategies, Chapter 15 proposes scope and sequence of training programs addressed to utilities personnel, Chapter 16 outlines how to deal with SAS projects, Chapter 17 offers a number of tips useful to help in getting timely acceptable SAS components and functionalities, Chapter 18 summarizes resources to be used and methodology to be followed for the engineering process according to Standard IEC 61850, and finally, Chapter 19 forecasts where control and monitoring technologies may go in the future.
In summary, the book intends to serve the practical needs of different participants in SAS projects with respect to technical matter and also from the management perspective.
Evelio Padilla
Acknowledgments
I would like to gratefully acknowledge several people for their valuable help on this book.
Firstly to all Wiley staff including Laura Bell, Assistant Editor, who was my initial contact with the company (and subtly followed with the publishing idea); Peter Mitchell, Publisher, Electrical Engineering, who achieved the tremendous goal of getting approval for the book project; Ella Mitchell, Associate Commissioning Editor, ever enthusiast in charge of extensive previous details and formal arrangements for the book project; Richard Davis, initial Project Editor, who gave me the guidelines related to the process for writing the book; Prachi Sinha Sahay, temporary Project Editor, who with patience and wisdom dealt with the completed manuscript, and Liz Wingett, the Project Editor who masterly cooperated in the process of adding value to the entire manuscript.
Thanks to Professors Nelson Bacalao and Greg Woodworth of Siemens Energy, who, as reviewers of the book project, found it to be feasible and contributional to the power industry.
My daughter, Jessenia, and her husband, Vinicio, provided me with precious and constant support and encouragement during the preparation of the manuscript.
My partner, Maria, was generous in her understanding and patience during the writing process.
I am also grateful for the training and support received from my employer EDELCA (currently CORPOELEC), as well as Carabobo University for my higher degree education.
CORPOELEC kindly gave their permission to include all the photos that appear in the book.
Yunio Leal, Julio Aponte and Zurima Alfonzo were outstanding collaborators during my working stay in EDELCA.
My appreciation is also expressed to my parents, Juanpa and Clara Rosa, who supported my early education; to my brother, Elias, and my sister, Argelia, for always identifying with my professional career; my sons, Armando and Alejandro, permanent inspiration sources, and mathematician, Professor Daniel Labarca, who inspired me to become an engineering professional.
Finally, the biggest thanks to God; because without His guidance, nothing is possible.
Evelio Padilla
List of Abbreviations
AC
Alternating voltage system
A/D
Analog/digital
APT
Auxiliary power transformer
AV
Analog value
BB
Busbar
BC
Bay controller
BC-AS
Bay controller for auxiliary system
BF
Breaker failure
BI
Binary input
BIL
Basic impulse level
BO
Binary output
BPD
Bushing potential device
CB
Circuit breaker
CIGRE
International Council on Large Electric Systems (Conseil International des Grands Réseaux Électriques)
CPU
Central processing unit
CT
Current transformer
DB
Database
DC
Direct voltage system
DG
Diesel generator
DI
Disconnector
DR
Disturbance recorder
DNP
Distributed network protocol
EMC
Electromagnetic compatibility
EMI
Electromagnetic interference
ES
Earthing switch
GOOSE
Generic object oriented substation event
GPS
Global positioning system
HMI
Human machine interface
HV
High voltage
HW
Hardware
IEC
International Electrotechnical Commission
IEEE
Institute of Electrical and Electronics Engineers
IED
Intelligent electronic device
IT
Information technology
I/O
Input/output
LAN
Local area network
LCD
Local control display
LV
Low voltage
MCB
Mini circuit breaker
MMS
Manufacturing message specification
MTTF
Mean time to failure
MU
Merging unit
MV
Medium voltage
MVA
Mega-volt ampere
NCC
Network control center
OLTC
On-load tap changer
OPGW
Optical grounding wire
PB
Process bus
PC
Personal computer
PCG
Protocol converter gateway
PR
Protective relay
PT
Power transformer
RTU
Remote terminal unit
SAS
Substation automation system
SB
Station bus
SC
Station controller
SCL
Substation configuration description language
SF6
Sulfur hexafluoride
SLD
Single line diagram
SOE
Sequence of events
SV
Sampled values
SVC
Static var compensator
VT
Voltage transformer
1Historical Evolution of Substation Automation Systems (SASs)
The key goal in the operation of electrical power systems is to maintain the energy balance between generation and demand in an economic manner. This often requires changes in system configuration to keep voltage and frequency parameters at acceptable pre-specified ranges; furthermore, configuration changes are needed for maintenance work at utility installations or for clearing faults due to short-circuit currents. Typical changes in system configurations include connection and disconnection of generators, power transformers, transmission lines, shunt reactors and static reactive power compensators. Therefore, such changes in system configuration are made through control facilities available in both generation stations and substations located along transmission and distribution systems (see a view of a substation in Figure 1.1).
Figure 1.1 View of a 765 kV electric substation.
Source: © Corpoelec. Reproduced with permission of Corpoelec
Until a few decades ago, the control of electric substations was based on systems consisting of discrete electronic or electromechanical elements, where several functions were carried out separately by specific subsystems. Although those arrangements were reliable because the failure of a subsystem does not affect the performance of the rest of control facilities, it was also quite expensive, as they require a large investment in wiring, cubicles and civil engineering work. Back then, stations were controlled through a large mimic control board located in the main control house, as shown in Figure 1.2.
Figure 1.2 Old mimic control board.
Source: © Corpoelec. Reproduced with permission of Corpoelec
Sometimes, primary arrangements of substations were placed outside control cubicles lodged in dedicated relay rooms (Figure 1.3).
Figure 1.3 Substation primary arrangement shown outside control cubicles.
Source: © Corpoelec. Reproduced with permission of Corpoelec
One of the most emblematic components of that age was the flag relay shown in Figure 1.4, which was the main way to display alarms for the attention of the substation operator.
Figure 1.4 Flag relay.
Source: © Corpoelec. Reproduced with permission of Corpoelec
In terms of civil engineering work, some substations were provided with large concrete channels where several kilometers of copper cables were run, as shown in Figure 1.5.
Figure 1.5 Old cabling channels.
Source: © Corpoelec. Reproduced with permission of Corpoelec
When microprocessor based substation control systems were originally developed, they were conceived as RTU-centric architecture, and later a distributed LAN architecture became the predominant technology. In more recent years, when control systems and other secondary systems began to incorporate new communication technologies and Intelligent Electronic Devices (IEDs), the complete set of secondary facilities and functionalities was referred to as “Substation Automation Systems” (SASs).
1.1 Emerging Communication Technologies
Development of communication technologies represents an important step allowing SASs to be more and more versatile and increase functionality. The most influential new technologies applied in substations are described in the following sections.
1.1.1 Serial Communication
Serial communication is the process of sending data one bit at a time, over a single communication line. In contrast, parallel communication requires at least as many lines as there are bits in a word being transmitted. This kind of communication was widely used at the beginning of the digital technology incursion in substations; in particular for relay to relay connections through a RS-232 interface. In recent years, instead of serial communication, Ethernet connectivity is gaining a place.
1.1.2 Local Area Network
As a group of computers/devices connected together locally to communicate with one another and share resources, this solution was early dedicated to office environments and later introduced to industrial applications, including substations. The use of LANs in a substation is increasing, in particular the Ethernet LAN specified in Standard IEEE 802.3.
1.2 Intelligent Electronic Devices (IEDs)
Generally, this refers to any device provided with one or several microprocessors able to receive/send data to or from another element. The most common IEDs used in substations are the following types:
1.2.1 Functional Relays
Digital relays (sometimes called computer relays, numerical relays or microprocessor-based relays) are devices that accept inputs and process them using logical algorithms to develop outputs addressed to make decisions resulting in trip commands or alarm signals. Early on, this kind of relay was designed to replace existing electromechanical or electronic protective relays and some years later they were also extended for use in control and monitoring functions.
1.2.2 Integrated Digital Units
Integrated digital units (also called multifunctional relays) have been developed for improving the efficiency of the substation secondary system decreasing the total cost of the asset by adding, in one element, several functions such as protection, control, monitoring and communication. This kind of device is widely used in particular for medium voltage substations where required availability is not a critical aspect.
1.3 Networking Media
The physical structure of LANs compresses cabling segments and connectivity devices allow computers and other IEDs connected to the LAN to share data and communicate. In the past, these elements were made up of copper wires and standardized communication ports and interfaces. Nowadays, these networking media are made with the following resources:
1.3.1 Fiber-Optic Cables
The use of optical technology eliminates the need for thousands of copper wires in a substation and replaces them with a few fiber-optic cables, making savings derived from installation and maintenance work while at the same time increasing worker safety and power system reliability. The main technical advantages in using fiber-optic cables in substations include high immunity to electrical interference and generous bandwidth. Today, the industry offers standardized fiber systems compatible with IEC 61850 devices oriented at reducing the chance of mistakes and minimizing costs in testing and commissioning activities.
1.3.2 Network Switches
These components are required to network multiple devices in a LAN. Their main function is to forward data from one device to another on the same network. They do it in an efficient manner since data can be directed from one device to another without affecting other devices on the same network. The most popular network switch used today in substations is the Ethernet switch, with different features or functions.
1.4 Communication Standards
Standards development is currently like “the motor” for SAS evolution. Initially, the Standard IEC 61850 had solved the important paradigm of vendor dependence that was blocking the advances in digital SAS installation for some years. Now, the Standard IEEE 803.2 allows an increase in networking facilities and functionalities. Both standards represent the state of art of SAS design and implementation as we know today, bringing clear rules for hardware design trends by manufacturers and more confidence in SAS users worldwide.
1.4.1 IEC Standard 61850 (Communication Networks and Systems for Power Utility Automation)
This Standard is a collection of publications intending to satisfy existing and emerging needs of the power transmission industry keeping interoperability as the main goal (allowing IEDs provided by different vendors to exchange data and work together in an acceptable manner). The Standard is based on continuous research and studies carried out by prestigious institutions such as UCA, CIGRE and IEEE, as well as the IEC itself. The scope of the standard currently is mainly addressed at the following:
Technically define communication methods and specify their quality attributes.
Provide guidelines for SAS project management and network engineering.
Give recommendations for SAS testing and commissioning.
Establish procedures for communication between substations.
Define methods for communication between substations and remote control facilities.
Provide guidelines for wide area control and monitoring.
The IEC still continues to develop several new areas. Utilities are waiting for them.
1.4.2 IEEE Standard 802.3 (Ethernet)
This standard defines the communication protocol called the “Carrier Sense Multiple Access Collision Detect” (CSMA/CD), which works under the broadcasting principle of carrying all delivered messages to all IEDs connected to a LAN. Currently, the standard maintains leadership on a LAN substation since such protocols were adopted by the IEC 61850 Standard as their communication platform. IEEE is very active in introducing innovations as the basis for network protocols, leaving behind a long history of proprietary protocols.
All these technological changes now provide the opportunity to have comfortable solutions for SAS design at reasonable cost and with reasonable levels of risk, in such a way that modern SAS are equipped with clean and sophisticated control cubicles lodged in appropriate control rooms (see Figure 1.6), and are operated from the main control house by means of ergonomic control desks such as that shown in Figure 1.7. This allows substation owners to get a high performance system characterized by excellent availability and reliability.
Figure 1.6 Control cubicles of a modern SAS.
Source: © Corpoelec. Reproduced with permission of Corpoelec
Figure 1.7 Operation desk of a modern SAS.
Source: © Corpoelec. Reproduced with permission of Corpoelec
Further Reading
Andersson, L. and Wimmer, W. (October 2001) Some aspects of migration from present solutions to SA systems based on the communication Standard IEC 61850,
2nd International Conference: Integrated Protection, Control and Communication – Experience, Benefits and Trends,
New Delhi, India.
Brand, K.P. (2004) Design of IEC 61850 based substation automation systems according to customer requirements, Paper B5–103, CIGRE Session 2004.
CIGRE Working Group 35.04 (February 2001) Optical Fiber cable selection for electricity utilities
Electra Review
194, 49–51.
CIGRE Working Group B5.07 (April 2004) The automation of new and existing substations: Why and how.
Electra Review
215, 53–57.
CIGRE Working Group D2.13 (August 2005) Web technology for the utility environment. Communication networks for web-based and non web-based applications.
Electra Review
221, 30–36.
IEC 61850, Communication networks and systems for power utility automation, (
www.iec.ch
).
IEEE 802.3, Standard for information technology – Telecommunications and information exchange between systems – Local and metropolitan area networks, Part 3: Carrier sense multiple accesses with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications.
Kruimer, B. (August 2003) Substation Automation – Historical Overview,
IEC Seminar
, Kema, Amsterdam.
Madren, F. (2004)
Ethernet in Power Utilities Substations – The Changing Role of Fiber Media
, GarrettCom, Inc.
Padilla, E. and Ceballos, L. (2006) Managing the transition to IEC 61850 standard on Substation Automation Systems,
China International Conference on Electricity Distribution
.
Singh, N. (February 2002) Substation control in the system control.
Electra Review
200, 41–53.
Tangney, B. and O’Mahony, D. (1988)
Local Area Networks and their Applications
, Prentice Hall, Hertfordshire.
Wester, C. and Adamiak, M. (n.d.)
Practical Applications of Ethernet in Substations and Industrial Facilities
, Internal paper GE Digital Energy Multilin.
