IEC 62270:2013

IEC 62270
Edition 2.0 2013-09
™
IEEE Std 1249
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Guide for computer-based control for hydroelectric power plant automation

Guide pour l'automatisation des centrales hydroélectriques à l’aide de systèmes
de commande informatiques
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IEC 62270
Edition 2.0 2013-09
IEEE Std 1249™
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Guide for computer-based control for hydroelectric power plant automation

Guide pour l'automatisation des centrales hydroélectriques à l’aide de systèmes

de commande informatiques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XB
ICS 27.140 ISBN 978-2-8322-1077-2

IEC 62270
IEEE Std1249 – i –
CONTENTS
FOREWORD . 1
1 Overview . 3
1.1 Scope . 3
1.2 Purpose . 3
2 Terms and definitions . 3
3 System architecture . 8
3.1 General . 8
3.2 Process control system configurations . 8
3.2.1 Basic configuration . 8
3.2.2 Control system configuration alternatives . 9
3.3 System architecture characteristics . 10
3.3.1 General . 10
3.3.2 Hierarchy . 10
3.3.3 Control locations and levels . 11
3.3.4 Interface between the control system and the controlled process . 12
3.4 Local individual control . 12
3.5 Local control . 13
3.6 Central (remote) control . 13
3.7 Off-site control . 14
4 Control Functions. 14
4.1 Local control functions . 14
4.1.1 Start/stop sequencing . 14
4.1.2 Synchronizing . 15
4.1.3 Synchronous condenser mode . 15
4.1.4 Pumped storage control . 15
4.1.5 Turbine operation optimization . 16
4.1.6 Trashrack control . 16
4.1.7 Environmental control . 16
4.1.8 Black start control . 17
4.2 Centralized control functions . 17
4.2.1 Control of individual units . 17
4.2.2 Switchyard, spillway, and station service control . 18
4.2.3 Plant active power (MW) control . 18
4.2.4 Plant reactive power (Mvar) control . 18
4.2.5 Water and power optimization . 18
4.2.6 Water bypass control . 19
4.3 Offsite control functions . 19
4.3.1 Control of individual generator sets and selection of centralized control
functions . 19
4.3.2 Switchyard, spillway, and station service control . 20
4.3.3 Automatic generation control (AGC) . 20
4.3.4 Automatic voltage control (AVC) . 20

Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
– ii – IEEE Std 1249
4.3.5 Remedial action schemes (RAS) . 21
4.4 Typical control parameters . 21
4.5 Interfaces to other computerized systems . 22
4.5.1 Fire detection data . 22
4.5.2 Plant security system . 23
4.5.3 Maintenance management system . 23
4.5.4 Plant conditioning monitoring . 23
5 Data acquisition and processing . 23
5.1 Data integrity . 23
5.2 Data acquisition capabilities . 24
5.3 Analog . 24
5.4 Discrete . 25
5.4.1 Status points . 25
5.4.2 Event points . 25
5.4.3 Calculated points. 25
5.4.4 Postmortem points . 25
5.5 Alarm processing and diagnostics . 25
5.6 Report generation . 26
5.7 Data archival and retrieval . 26
5.7.1 Operation scheduling and forecasting . 26
5.7.2 Data access and security . 27
5.7.3 Operator simulation training . 27
6 Communications and data bases . 27
6.1 Overview. 27
6.2 Communications . 27
6.2.1 General . 27
6.2.2 Open system standards . 27
6.2.3 Digital communication systems at the field level . 28
6.2.4 Hydroelectric plant automation classification . 28
6.2.5 Networking and communication considerations . 29
6.2.6 Data communication functions . 30
6.2.7 Control data communication requirements . 30
6.3 Control data networks . 33
6.3.1 General . 33
6.3.2 Local area network (LAN) topologies . 33
6.3.3 Physical transmission mode . 37
6.4 Data bases and software configuration . 37
6.4.1 Open systems and data bases . 37
6.4.2 Real-time vs. nonreal-time database designs . 38
6.4.3 Software configuration . 39
7 User and plant interfaces . 40
7.1 User interfaces . 40
7.1.1 Input devices . 40
7.1.2 Output devices . 40
7.2 Plant equipment interfaces . 40

Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
IEEE Std1249 – iii –
7.2.1 Types . 40
7.2.2 Sources . 42
7.2.3 Input/output protection . 42
7.2.4 Collection process . 43
7.3 Security considerations . 43
7.4 Ergonomic and maintenance considerations . 43
7.5 User interface considerations . 44
8 System performance . 44
8.1 General . 44
8.2 Software . 45
8.3 Hardware . 45
8.3.1 Input/output (I/O) subsystem . 45
8.3.2 Control processing subsystems . 46
8.4 Communications . 47
8.5 Maintenance performance . 47
8.6 Measuring performance . 48
8.6.1 Functionality . 48
8.6.2 Real time ability . 48
8.6.3 Availability . 49
8.6.4 System initialization and fail-over times . 50
9 System backup capabilities . 50
9.1 General . 50
9.2 Design principles . 50
9.3 Basic functions . 51
9.4 Design of equipment for backup control . 51
9.4.1 Turbine/generator units . 51
9.4.2 Circuit breakers and isolating switches (local control) . 51
9.4.3 Governor and excitation systems (local control) . 51
9.4.4 Spillways and intake gate/turbine isolation (shutoff) valve . 52
9.5 Alarm handling . 52
9.6 Protective function . 52
10 Site integration and support systems. 52
10.1 Overview. 52
10.2 Interface to other equipment . 52
10.3 Environmental considerations . 53
10.4 Power source . 53
10.5 Supervision of contact status points . 54
10.6 Supervision of transducers . 55
10.7 Supervision of IED or field bus devices . 55
10.8 Control output points . 55
10.9 Grounding . 55
10.10 Static control . 55
11 Recommended test and acceptance criteria . 56
11.1 Overview. 56
11.2 Specific test requirements . 56

Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
– iv – IEEE Std 1249
11.2.1 Factory acceptance test . 56
11.2.2 Field test. 57
11.3 Quality assurance . 57
11.4 Acceptance . 58
12 System management . 58
12.1 Maintenance . 58
12.2 Training . 58
12.2.1 Training plan . 58
12.2.2 Courses . 59
12.3 Documentation . 59
12.3.1 Design documentation . 59
12.3.2 System support documentation . 60
12.4 Archive . 60
Annex A (informative) Bibliography . 61
Annex B (informative) Legacy control systems . 65
Annex C (informative) IEEE list of participants . 68

Figure 1 – Generic control system configuration . 9
Figure 2 – System with dedicated unit control processors . 10
Figure 3 – Relationship of local, centralized and off-site control . 12
Figure 4 – Typical functions − Unit local control board . 13
Figure 5 – Multi-point data link versus LANs . 33
Figure 6 – Star topology . 35
Figure 7 – Ring topology . 35
Figure 8 – Bus topology . 36

Table 1 – Summary of control hierarchy for hydroelectric power plants . 11
Table 2 – Typical parameters necessary to implement automated control . 21
Table 3 – Classifications of hydroelectric power plant computer control systems . 29
Table 4 – Hydroelectric computer control systems data communications attributes . 36
Table 5 – Cable media characteristics. 37

Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
IEEE Std1249 – v –
Guide for Computer-Based Control
for Hydroelectric Power Plant
Automation
Sponsor
Energy Development and Power Generation Committee
of the
IEEE Power & Energy Society
IEEE-SA Standards Board
Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
– vi – IEEE Std 1249
Abstract: The application, design concepts and implementation of computer-based control
systems for hydroelectric power plant automation is addressed. Functional capabilities,
performance requirements, interface requirements, tradeoffs, and hardware considerations and
operator training are discussed, including typical application examples.
Keywords: 62270, applications, computer-based control systems, functional capabilities,
hardware considerations, hydroelectric power plant automation, hydroelectric power station, IEEE
1249™, interface requirements, operator training, performance requirements, recommendations
•
___________
Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
IEEE Std 1249 – vii –
IEEE Notice to users
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IEC 62270
– viii – IEEE Std 1249
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IEC 62270
IEEE Std 1249 – ix –
IEEE INTRODUCTION
This introduction is not part of IEEE Std 1249, Guide for Computer-Based Control for Hydroelectric Power Plant
Automation
This document is a guide for the power industry for the automation of hydroelectric power plants
using computer-based controls. The document was prepared by the Working Group on
Computer-Based Control for Hydroelectric Power Plant Automation of the Hydroelectric Power
Subcommittee of the Energy Development and Power Generation Committee of the IEEE Power
and Energy Society (PES).
Automation of hydroelectric generating plants has been a proven technology for many years.
However due to the relative simplicity of the control logic for hydroelectric power plants, the
application of computer-based control on hydro power plants lagged, as compared to applications
on thermal generating stations. With the advent of economic, computer-based control systems in
the 1980s, installations of these systems in hydroelectric power plants has proceeded at a rapid
pace worldwide, for both new installations and rehabilitation of control systems in existing plants.
Since preparation of the original guide, significant changes in technology and application criteria
have occurred. The purpose of this revision is to address these changes and to harmonize this
guide with a companion document, IEEE Std 1010™, IEEE Guide for the Control of Hydroelectric
Power Plants.
The guide is directed to the practicing engineer who has some familiarity with computer-based
control systems. It contains references and definitions for use with the guide. Clauses addressing
functional capabilities, software, security, system integration, system architecture, data bases,
user and plant interfaces, system performance, back-up capabilities, support systems, testing and
acceptance criteria and system management are contained in the guide.

Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
– x – IEEE Std 1249
Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
IEEE Std 1249 – 1 –
GUIDE FOR COMPUTER-BASED CONTROL
FOR HYDROELECTRIC POWER PLANT AUTOMATION

FOREWORD
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Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
– 2 – IEEE Std 1249
International Standard IEC 62270/IEEE Std 1249 has been jointly revised by the Energy
Development & Power Generation Committee of the IEEE Power & Energy Society, in cooperation
with IEC technical committee 4: Hydraulic turbines, under the terms of that agreement.
This second edition cancels and replaces the first edition published in 2004. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) update of system architecture aspects, with different process control system configurations;
b) update of communications, user and plant interfaces aspects;
c) suppression of case studies, because of the quickness of evolution of the technology;
d) complete review of the bibliography, making mention of many IEC and IEEE standards as new
references;
e) addition of a new informative Annex B on legacy control systems.
This publication is published as an IEC/IEEE Dual Logo standard.
The text of this standard is based on the following IEC documents:
FDIS Report on voting
4/284/FDIS 4/287/RVD
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Published by IEC under license from IEEE. © 2013 IEEE. All rights reserved.

IEC 62270
IEEE Std 1249 – 3 –
GUIDE FOR COMPUTER-BASED CONTROL
FOR HYDROELECTRIC POWER PLANT AUTOMATION

1 Overview
The automation of control and data logging functions has relieved the plant operator of these
tasks, allowing the operator more time to concentrate on other duties. In many cases, the plant’s
operating costs can be significantly reduced by automation (primarily via staff reduction) while still
maintaining or increasing the plant reliability.
Automatic control systems for hydroelectric units based on electromechanical relay logic have
been in general use for many years and, in fact, were considered standard practice for the
industry. Within the past few decades, microprocessor-based controllers have been developed
that are suitable for operation in a power plant environment. These computer-based systems have
been applied for data logging, alarm monitoring, and unit and plant control. Advantages of
computer-based control include use of graphical user interfaces, the incorporation of sequence of
events and trending and automatic archiving and reporting into the control system and the
incorporation of artificial intelligence and expert system capabilities.
1.1 Scope
This guide addresses the application, design concepts, and implementation of computer-based
control systems for hydroelectric plant automation. It addresses functional capabilities,
performance requirements, interface requirements, hardware considerations, and operator
training. It includes recommendations for system testing and acceptance. The electrical protective
system (generator and step-up transformer) is beyond the scope of this guide.
1.2 Purpose
This guide is directed to the practicing engineer who has some familiarity with computer-based
control systems and who is designing or implementing hydroelectric unit or plant control systems,
either in a new project or as a retrofit to an existing one. Although this guide is aimed primarily
towards large hydroelectric power plants, many of the concepts are applicable for small
hydroelectric power plants (i.e. unit size 5 MVA or smaller). Further details on small hydroelectric
,
1 2
power plant control concepts can be found in IEEE Std 1020™ [B46]. Typical hydroelectric
system control logic upon on which this guide is based can be found in companion guide IEEE Std
1010™ [B45] or IEC 61362 [B22].
2 Terms and definitions
The terms and definitions provided here reflect common industry usage as related to automation
of hydroelectric power plants, and may not in all instances be in accordance with IEEE Standards
___________
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Piscataway, NJ 08854, USA (http://standards.ieee.org/).
2 The number in square brackets refer to the references listed in the bibliography in Annex A.
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131, 3 rue de Varembé, CH-1211, Genève 20, Switzerland/Suisse (http://www.iec.ch/). IEC publications are also
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Street, 13th Floor, New York, NY 10036, USA.

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IEC 62270
– 4 – IEEE Std 1249
Dictionary Online [B39], IEEE Std 610.12 [B41] or IEC 60050-351 [B2] or other applicable
standards. For more rigorous terms and definitions, or for terms and definitions not covered
herein, the reader is referred to the appropriate IEEE and IEC standards.
2.1 analog-to-digital (a/d) conversion
production of a digital output signal corresponding to the value of an analog input quantity
2.2 automatic control
an arrangement of electrical controls that provides for switching or controlling, or both, of
equipment in a specific sequence and under prede
...