IEC 62270:2013

Guide for computer-based control for hydroelectric power plant automation

IEC 62270:2013 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. 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:
- update of system architecture aspects, with different process control system configurations;
- update of communications, user and plant interfaces aspects;
- suppression of case studies, because of the quickness of evolution of the technology;
- complete review of the bibliography, making mention of many IEC and IEEE standards as new references and addition of a new informative Annex B on legacy control systems. This publication is published as an IEC/IEEE Dual Logo standard. Key words: Hydroelectric, Automation, Computer-Based Control

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

La CEI 62270:2013 traite de l'application, la conception et la mise en eouvre de systèmes de commande informatiques destinés à l'automatisation des centrales hydroélectriques. Il décrit les capacités fonctionnelles, les exigences de performance, les exigences applicables aux interfaces, les considérations matérielles et la formation des opérateurs. Il inclut des recommandations pour les essais et la réception des systèmes. Le système de protection électrique (générateur et transformateur élévateur de tension) ne fait pas partie du domaine d'application du présent guide. Cette deuxième édition annule et remplace la première édition parue en 2004. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- mise à jour des aspects architecture du système, avec les différentes configurations du système de commande de processus;
- mise à jour des aspects communications, interfaces utilisateur et interfaces avec la centrale;
- suppression des études de cas, en raison de la rapidité d'évolution de la technologie;
- revue complète de la bibliographie, avec mention de nombreuses normes IEC et IEEE comme nouvelles références;
- ajout d'une nouvelle Annexe B informative sur les systèmes de commande obsolètes. La présente publication est une norme double logo CEI/IEEE. Mots-Clés: Hydroelectrique, Automatisation, Systemes de Commande Informatiques

General Information

• Status: Published
• Publication Date: 15-Sep-2013
• ICS: 27.140 - Hydraulic energy engineering
• Technical Committee: TC 4 - Hydraulic turbines
• Drafting Committee: WG 14 - TC 4/WG 14
• Current Stage: PPUB - Publication issued
• Start Date: 16-Sep-2013
• Completion Date: 30-Sep-2013

Relations

• Revises: IEC 62270:2004 - Hydroelectric power plant automation - Guide for computer-based control
• Effective Date: 05-Sep-2023

Overview

IEC 62270:2013, titled Guide for computer-based control for hydroelectric power plant automation, is an international standard developed by the International Electrotechnical Commission (IEC) in collaboration with the Institute of Electrical and Electronics Engineers (IEEE). It provides comprehensive guidance on the design, application, and implementation of computer-based control systems specifically for hydroelectric power plants. This second edition updates architectural aspects, communication and interface requirements, and includes new references to contemporary IEC and IEEE standards. However, it excludes electrical protective systems related to generators and step-up transformers.

The guide emphasizes functional capabilities, performance criteria, hardware considerations, operator training, system testing, and acceptance of automation systems. It also addresses multiple control system configurations including local, central, and off-site control levels. The standard targets engineers, system designers, and plant operators involved in hydroelectric plant automation, promoting secure, robust, and optimal plant operation through advanced computer-based controls.

Key Topics

• System Architecture
  The standard details various process control system configurations for hydroelectric plants, including hierarchical structures and interfaces between control systems and plant processes. It outlines options such as local individual control, local centralized control, and remote or off-site control to suit diverse operational needs.

• Control Functions
  It covers essential control functionalities such as start/stop sequencing, synchronizing, synchronous condenser modes, pumped storage control, and turbine operation optimization. The guide also discusses centralized control of plant active and reactive power, spillways, switchyards, and black start control procedures.

• Data Acquisition and Processing
  IEC 62270 highlights key data acquisition capabilities, stressing data integrity, analog and discrete input types, alarms, diagnostics, and the management of reports and data archiving. It also considers operator simulation training, forecasting, and secure data access.

• Communications and Databases
  The publication promotes the use of open communication standards and digital communication systems at the field level. It elaborates on network topologies for local area networks, data communication functions, and real-time database designs crucial for reliable hydroelectric plant automation.

• User and Plant Interfaces
  Adequate user interface design is emphasized, including ergonomic considerations, input/output devices, and interface security. The guide advocates for efficient communication between plant equipment and operators to enhance monitoring and control.

• System Performance & Backup
  The standard addresses software and hardware performance requirements, maintenance considerations, availability, fail-over times, and system initialization. It also details backup control systems' design principles to ensure operational continuity in the event of failures.

Applications

IEC 62270:2013 is applicable to the automation of hydroelectric power plants of various sizes and configurations. Its guidance facilitates:

• Designing computer-based control systems tailored to hydroelectric plant operational requirements.
• Enhancing plant reliability through well-defined system architectures and redundant controls.
• Optimizing plant performance, including active and reactive power management, water resource optimization, and environmental control.
• Improving operator training programs using data acquisition and simulation tools.
• Integrating automated controls with ancillary systems such as fire detection, security, and maintenance management.
• Providing robust communication frameworks leveraging open standards to future-proof plant control systems.

The standard supports utilities, engineering firms, and manufacturers aiming to deploy efficient and secure hydroelectric automation solutions compliant with international best practices.

Related Standards

When implementing IEC 62270:2013, consider complementing it with other relevant standards for comprehensive system coverage:

• IEC 61131 - Programmable controllers - for automation programming standards.
• IEC 61850 - Communication networks and systems in substations - relevant for switchyard and substation automation interfaces.
• IEEE Std 1249 - Corresponding IEEE guide aligned with IEC 62270 for hydroelectric plant control automation.
• IEC 61508 - Functional safety of electrical/electronic systems - to ensure safety aspects beyond control automation.
• ISO/IEC 27001 - Information security management - for securing communication and control interfaces.

Adhering to these international standards ensures that hydroelectric power plant automation systems are designed with best-in-class safety, functionality, and interoperability, fostering sustainable and reliable energy production.

Standards Content (Sample)

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 –
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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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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.
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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
___________
1 IEEE publications are available from the Institute of Electrical and Electronics Engineers, 445 Hoes Lane,
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.
3 IEC publications are available from the Sales Department of the International Electrotechnical Commission, PO Box
131, 3 rue de Varembé, CH-1211, Genève 20, Switzerland/Suisse (http://www.iec.ch/). IEC publications are also
available in the United States from the Sales Department, American national Standards Institute, 11 West 42nd
Street, 13th Floor, New York, NY 10036, USA.

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

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
...