EN 61975:2010/A1:2017

SLOVENSKI STANDARD
01-april-2017
Visokonapetostne enosmerne inštalacije (HVDC) - Sistemski preskusi (IEC
61975:2010/A1:2016) - Dopolnilo A1
High-voltage direct current (HVDC) installations - System tests (IEC
61975:2010/A1:2016)
Ta slovenski standard je istoveten z: EN 61975:2010/A1:2017
ICS:
29.130.10 Visokonapetostne stikalne in High voltage switchgear and
krmilne naprave controlgear
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 61975:2010/A1

NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2017
ICS 29.130.10; 31.080.01
English Version
High-voltage direct current (HVDC) installations - System tests
(IEC 61975:2010/A1:2016)
Installations en courant continu à haute tension (CCHT) - Anlagen zur Hochspannungsgleichstromübertragung (HGÜ)
Essais systèmes - Systemprüfungen
(IEC 61975:2010/A1:2016) (IEC 61975:2010/A1:2016)
This amendment A1 modifies the European Standard EN 61975:2010; it was approved by CENELEC on 2016-10-17. CENELEC members
are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this amendment the status of a
national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This amendment exists in three official versions (English, French, German). A version in any other language made by translation under the
responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the same status as
the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 61975:2010/A1:2017 E

European foreword
The text of document 22F/375/CDV, future IEC 61975:2010/A1, prepared by SC 22F “Power
electronics for electrical transmission and distribution systems” of IEC/TC 22 “Power electronic
systems and equipment” was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN 61975:2010/A1:2017.

The following dates are fixed:
• latest date by which the document has to be (dop) 2017-08-10
implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2020-02-10
• latest date by which the national
standards conflicting with the
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 61975:2010/A1:2016 was approved by CENELEC as a
European Standard without any modification.
IEC 61975 ®
Edition 1.0 2016-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
AM ENDMENT 1
AM ENDEMENT 1
High-voltage direct current (HVDC) installations – System tests

Installations en courant continu à haute tension (CCHT) – Essais systèmes

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.130.10; 31.080.01 ISBN 978-2-8322-3610-9

– 2 – IEC 61975:2010/AMD1:2016
© IEC 2016
FOREWORD
This amendment has been prepared by subcommittee 22F: Power electronics for electrical
transmission and distribution systems, of IEC technical committee 22: Power electronic
systems and equipment.
The text of this amendment is based on the following documents:
CDV Report on voting
22F/375/CDV 22F/394A/RVC
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC website 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.
_____________
General:
Replace throughout the text the abbreviations "a.c" and "d.c" by the abbreviations "AC" and
"DC" respectively.
Introduction
Delete listing using a) to l).
Replace, in c), the word "Definitions" by the words "Terms and definitions"
Replace, in d), the word "General" by the words "Objectives of system tests".
Delete, in h), the word "Power".
Replace, in the first line of the last paragraph, the word "objects" by the word "objectives".
1 Scope
Add, in the first sentence of the second paragraph, the word "monopolar" after the word
"bidirectional"
Delete, in the third paragraph, the word "some".

IEC 61975:2010/AMD1:2016 – 3 –
© IEC 2016
2 Normative references
Replace, in the last sentence of the first paragraph, the word "updated" by the word "undated".
3. Terms and definitions
3.1.1
station test
Replace the existing term and definition by the following new term and definition:
3.1.1
converter station tests
converter station system test including items which verify the function of individual equipment
of the converter station in energized state
Add, after 3.1.3, the following new terms and definitions:
3.1.4
on-site tests
tests which are performed at the final construction site consisting of converter station test and
transmission test
3.2 Operation state terms
Replace the first sentence by the following note:
NOTE There are five defined states in the HVDC system: earthed, stopped, standby, blocked, de-blocked.
3.2.3
standby
Replace, in the definition, "DC" by "HVDC".
Add, after the last sentence of the note, the following new sentence:
The standby state is also referred to as "Ready for energization".
3.2.4
blocked
Replace the second sentence of the note by the following new sentence:
The valve cooling system is in operation, and the cooling water conductivity, flow rate and water temperature are
within the specified limits.
Add, at the end of the note, the following new sentence:
The blocked state is also referred to as "Ready for operation".
3.2.6
off-site tests
Add, after the definition, the following new note:
EXAMPLE Routine and type tests performed at the suppliers’ factory.

– 4 – IEC 61975:2010/AMD1:2016
© IEC 2016
4 General
Replace the existing title by the following new title:
4 Objectives of system tests
4.1 Purpose
Replace the existing title by the following new title:
4.1 Categories of system tests
Replace, in the fourth paragraph, the word "test" by the word "testing".
Add, at the beginning of the second paragraph after Figure 1, the following new sentence:
Acceptance tests are the acceptance requirements for a successful completion of works and a
basis for the final acceptance of the HVDC system by its users.
4.2 Structure of the HVDC system
Replace, in the second sentence of the first paragraph, the word "converters" by the words
"converter units".
Add, before the last sentence of the first paragraph, the following new sentences:
Two terminals in connection constitute a HVDC system. If the configuration comprises a
single pole, it is defined as a monopolar HVDC system. If the configuration comprises two
poles of opposite polarities with respect to earth, it is called a bipolar HVDC system.
Replace Figure 2 by the following new figure:

IEC 61975:2010/AMD1:2016 – 5 –
© IEC 2016
Converter Converter
DC line/cable/bus
terminal terminal
Pole
Bipole
Pole
IEC
Figure 2 – Structure of the HVDC system
4.4 Logical steps of system test
Replace the existing text by the following new text:
To ensure proper functioning, the type test and functional performance test shall be
conducted in factory in order to debug and test the control system before the site test.
In order to provide the power grid data and help to compile the system test plan, the off-line
digital simulation shall be conducted before and during the simulation test, especially analysis
on the power flow, stability and overvoltage.
Considering the complexity of the HVDC system, all limiting design cases may be conducted
on the digital simulator in a similar way to those done on site.
Commissioning an HVDC system may affect more than the actual contract parties. The
complexity and the diversified areas concerned during system testing require thorough
planning and scheduling, cooperation of all involved parties and complete and structured
documentation. Before a system test can begin on site, the following preconditions shall be
fulfilled concerning subsystem tests, operator training and safety instructions, system test
plan and test procedures, and all necessary test equipment.
a) All subsystems shall have been tested and commissioned, including AC filters and the
converter transformers.
b) Operating personnel shall be sufficiently trained.

– 6 – IEC 61975:2010/AMD1:2016
© IEC 2016
c) Operating instructions for the station shall be available.
d) Personnel, plant safety and security instructions shall be available.
e) System test plan and documentation (Part 8) shall be available and agreed upon.
f) AC/DC power profiles shall have been agreed for each test.
g) Any AC/DC system operating restrictions shall have been identified.
h) Operator voice communications shall be available
i) All necessary test equipment shall have been calibrated and in service.
j) Procedures for the preparation and evaluation of test results shall have been agreed upon.
Site system tests shall follow the structure of the HVDC system, starting from the smallest,
least complex operational unit, usually a 12-pulse converter, and shall end with the total
system in operation. The test sequence shall be scheduled starting at the local level with
simple tests before involving additional locations and the transmission system and more
complex tests.
After all preconditions are fulfilled, converter station tests shall be conducted and begin from
the converter unit test, including the energization of AC filter and DC yard, changing the DC
system configuration, electromagnetic interference, trip test, open line test, etc.
The power transmission (also called end-to-end) test shall start on a monopolar basis,
continuing with bipolar operation, with full power transmission being the final step.
Having the complete system running properly, performance of the steady state can be verified.
With normal operating ramp settings and automatic switching sequences in place, the effect of
a number of disturbances on the DC side of the system as well as in the AC systems may be
checked, and the transient and fault recovery performances may be verified.
Acceptance tests shall be defined between supplier and user in advance and may be
performed at an appropriate time during the test schedule.
Correct operation of the HVDC system over an extended period of time is checked during the
trial operation.
Complete and organized documentation of the system tests, which benefit both the supplier
and the user, shall form part of the project documentation and contain all necessary data
records, logs, etc, and if necessary a commentary and references.
After all the above HVDC system tests have been completed, all functions have been verified
and the HVDC system can be handed over to the users.
4.5 Structure of system test
Replace the existing sentence by the following new sentence:
The overall structure of the system tests is shown in Figure 4.
4.6 Precondition for site test
Replace the existing title by the following new title:
4.6 Precondition for on-site test
4.6.1 Factory system test
Replace, in the first paragraph, the words "site tests" by the words "the off-site tests" and the
words "commissioning" by the words "partial commissioning".

IEC 61975:2010/AMD1:2016 – 7 –
© IEC 2016
Add, at the end of the fifth paragraph, the following new sentence:
Off-line simulation software can be used to analyse short circuit capacity, overvoltage and
power flow, while the real-time simulator may be used for the complete functional
performance tests of the control system.
Replace, in the first sentence of the sixth paragraph, the words "complete control system" by
the words "complete control and protection system".
4.6.2 Additional simulation test before site system test
Delete, in the existing title, the words "before site system test".
Replace the existing first paragraph by the following new paragraph:
If the AC network conditions in commissioning stage are different from that in the HVDC
design stage, the additional simulation test shall be conducted, if specified by the user.
Delete the second paragraph.
Add, after 4.6.2, the following new subclause:
4.7 Acceptance tests
The acceptance tests necessary to verify whether acceptance criteria have been met may
have been performed wholly or in part during the commissioning period. To avoid
unnecessary duplication of such tests, careful consideration shall be given in advance as to
when acceptance tests are carried out. If acceptance tests are still outstanding or have to be
repeated due to modifications, they shall be performed during the transmission test, or
following trial operation, if appropriate.
5.1.2.1 General
Replace, in the second paragraph, the words "divided into low voltage energizing" by the
words "divided into trip tests, low voltage energization".
5.1.2.2 Low voltage energizing / Phasing verification
Replace the existing title by the following new title:
5.1.2.2 Low voltage energization/Phasing verification
5.1.2.3 High voltage energizing
Replace, in the title, the word "energizing" by the word "energization"
5.1.3 General precondition
Add, in the first paragraph, the word "station" after the word "converter".
Add, in the last paragraph, the word "station" after the word "converter" and replace the words
"should" by the words "shall".
5.2.1 Purpose of test
Replace the existing text by the following new text:

– 8 – IEC 61975:2010/AMD1:2016
© IEC 2016
The test verifies that at the first energization of the converter unit the insulation withstand
voltage is achieved, and that the electrical phasing is correct.
5.2.2 Test precondition
Replace, in item a) of the list, the word "energizing" by the word "energization".
5.2.3.1 Low voltage energizing
Replace, in the title, the word "energizing" by the word "energization".
5.2.3.2 High voltage energizing
Replace, in the title, the word "energizing" by the word "energization".
5.2.3.3 Test acceptance criteria
Replace the existing subclause number by the following new subclause number:
5.2.4 Test acceptance criteria
Replace, in item c) of the list, the word "should" by the word "shall".
5.3 Energizing of reactive components
Replace, in the title, the word "energizing" by the word "energization".
5.3.1 Individual energizing of reactive components
Replace the existing title by the following new title:
5.3.1 General
5.3.3 Test precondition
Replace, at the end of item a) of the list, the word "energizing" by the word "energization".
5.4.1 General
Add, in the first sentence, the word "unit" after the word "converter".
5.4.2 Purpose of test
Replace the existing text by the following new text:
The test verifies that the different DC system configuration available can be safely changed
as specified prior to transmitting power for the first time.
5.5.1 General
Replace the existing title by the following new title:
5.5.1 Purpose of test
Add, after the existing sentence, the following new sentence:
The test verifies that there are no issues with electromagnetic compatibility of the equipment
cubicles.
IEC 61975:2010/AMD1:2016 – 9 –
© IEC 2016
5.6.4.2 DC protection trip test
Replace, in the existing sentence, the word "should" by the word "shall".
5.7.1 General
Replace the existing title by the following new title:
5.7.1 Purpose of test
5.7.1.1 Necessity of the test
Delete the title of 5.7.1.1.
Add, after the existing paragraph, the following new paragraph:
The test verifies condition and stable energization of the DC yard and DC transmission circuit.
It can excellently demonstrate the condition of the HVDC lines and cables. The tests shall be
performed sequentially. Open line test of the DC switch yard shall be the first.
Add, after the above new paragraph, the existing paragraph of 5.7.1.2 and the first sentence
of 5.7.1.3.
5.7.1.2 Open line test of the DC switchyard
Delete the title of 5.7.1.2.
5.7.1.3 Open line test with the DC transmission circuit
Delete the title of 5.7.1.3 and the last sentence of the existing paragraph.
5.7.3.2 Open line test with the DC transmission circui
...