IEC TR 63259:2022

IEC TR 63259 ®
Edition 1.0 2022-03
TECHNICAL
REPORT
Water cooling systems for power electronics used in electrical transmission and
distribution systems
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IEC TR 63259 ®
Edition 1.0 2022-03
TECHNICAL
REPORT
Water cooling systems for power electronics used in electrical transmission

and distribution systems
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.240.99 ISBN 978-2-8322-1090-5

– 2 – IEC TR 63259:2022 © IEC 2022
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Service conditions . 8
4.1 General . 8
4.2 Indoor conditions . 9
4.3 Outdoor conditions . 9
4.4 Electrical supply conditions . 9
5 Technical performance . 9
5.1 System functions . 9
5.2 Main circuit . 11
5.2.1 Design input parameters . 11
5.2.2 Components . 12
5.3 Heat exchanger . 14
5.3.1 General . 14
5.3.2 Air cooler . 14
5.3.3 Evaporative cooling tower . 15
5.3.4 Liquid-to-liquid heat exchanger . 16
5.3.5 Chiller unit . 17
5.4 Control and protection system . 17
5.4.1 General . 17
5.4.2 Control . 18
5.4.3 Protection . 18
5.4.4 Monitoring and recording . 19
5.5 Freezing prevention . 19
5.6 Rating plate . 19
6 Documentation . 19
7 Tests . 20
7.1 Summary of tests . 20
7.2 Description of tests . 20
7.2.1 Visual inspection . 20
7.2.2 Insulation test . 21
7.2.3 Pressure and leakage test . 21
7.2.4 Hydraulic performance test . 21
7.2.5 Thermal performance test . 21
7.2.6 Control and protection test . 21
7.2.7 EMC test . 21
7.2.8 Operation test . 21
7.2.9 Inspection of internal cleanliness . 21
7.2.10 Pump and motor alignment check . 22
7.2.11 Coolant freezing point check . 22
7.2.12 Vibration check . 22
7.2.13 Audible noise check . 22
7.2.14 Current check . 22

7.2.15 Communication and interface test . 22
8 Maintenance . 22
9 Safety . 22
10 Environmental impact . 22
Bibliography . 24

Figure 1 – Typical flow chart of water cooling system application . 11
Figure 2 – Typical flow chart of air cooler application . 15
Figure 3 – Typical flow chart of evaporative cooling tower application . 16
Figure 4 – Typical flow chart of water-to-water heat exchanger application . 16
Figure 5 – Typical flow chart of chiller unit application . 17

Table 1 – Typical design input parameters of water cooling system . 12
Table 2 – List of tests . 20

– 4 – IEC TR 63259:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
WATER COOLING SYSTEMS FOR POWER ELECTRONICS USED
IN ELECTRICAL TRANSMISSION AND DISTRIBUTION SYSTEMS

FOREWORD
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IEC TR 63259 has been prepared by subcommittee 22F: Power electronics for electrical
transmission and distribution systems, of IEC technical committee 22: Power electronic systems
and equipment. It is a Technical Report.
The text of this Technical Report is based on the following documents:
Draft Report on voting
22F/650/DTR 22F/668/RVDTR
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this Technical Report is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
...