IEC TR 62511:2014

IEC TR 62511 ®
Edition 1.0 2014-09
TECHNICAL
REPORT
Guidelines for the design of interconnected power systems
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IEC TR 62511 ®
Edition 1.0 2014-09
TECHNICAL
REPORT
Guidelines for the design of interconnected power systems

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
U
ICS 29.240.99 ISBN 978-2-8322-1865-5

– 2 – IEC TR 62511:2014 © IEC 2014
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 General principles . 14
4.1 General requirements . 14
4.2 System analysis and modeling data exchange requirements . 15
5 Resource adequacy . 15
6 Modeling and assessments . 16
6.1 General . 16
6.2 Stability assessment . 16
6.3 Steady state assessment . 17
6.4 Real time system conditions . 17
6.5 Normal transfers . 17
6.6 Emergency transfers . 18
6.7 Post contingency operation . 18
6.8 Operation under high risk conditions . 18
6.9 Extreme contingency assessment . 19
6.10 Extreme system conditions assessment . 19
6.11 Fault current assessment . 20
7 IPS design guidelines . 20
7.1 General . 20
7.2 Redundancy in transmission system design . 20
7.3 Protection and control system design . 20
7.4 Considerations for issues affecting protection systems reliability and
dependability . 22
7.5 Considerations for issues affecting security . 22
7.6 Considerations for issues affecting dependability and security . 22
7.7 Protection operating time . 23
7.8 Protection system testing . 23
7.9 Analysis of protection performance . 23
7.10 Considerations for current and voltage transformers . 23
7.10.1 AC current transformers . 23
7.10.2 AC voltage transformers (VT), capacitance coupler voltage transformer
(CCVT), and fiber optic voltage transducers . 24
7.11 Logic systems . 24
7.12 Microprocessor-based equipment and software . 24
7.13 Batteries and direct current (DC) auxiliary supply . 24
7.14 Station service AC supply . 25
7.15 AC circuit breakers . 25
7.16 Teleprotection (communication for protective functions) . 25
7.17 Control cables and wiring and ancillary control devices . 26
7.18 Environment . 26
7.19 Grounding . 26
7.20 Specific application considerations . 26
7.20.1 AC transmission line protection . 26

7.20.2 Transmission station protection . 27
7.20.3 AC breaker failure protection . 27
7.20.4 Generating station protection . 27
7.20.5 HVDC system protection . 28
7.20.6 AC capacitor bank protection . 28
7.20.7 Static VAR compensator (SVC) protection . 29
7.21 Reporting of protection systems . 29
Bibliography . 30

– 4 – IEC TR 62511:2014 © IEC 2014
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDELINES FOR THE DESIGN OF
INTERCONNECTED POWER SYSTEMS
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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The main task of IEC technical committees is to prepare International Standards. However, a
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data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC/TR 62511, which is a technical report, has been prepared by IEC technical committee 8:
Systems aspects for electrical energy supply.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
8/1346/DTR 8/1364/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

– 6 – IEC TR 62511:2014 © IEC 2014
GUIDELINES FOR THE DESIGN OF
INTERCONNECTED POWER SYSTEMS
1 Scope
The primary objective of this Techni
...