IEC 60099-9:2014

IEC 60099-9 ®
Edition 1.0 2014-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Surge arresters –
Part 9: Metal-oxide surge arresters without gaps for HVDC converter stations

Parafoudres –
Partie 9: Parafoudres à oxyde métallique sans éclateur pour postes de
conversion CCHT
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IEC 60099-9 ®
Edition 1.0 2014-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Surge arresters –
Part 9: Metal-oxide surge arresters without gaps for HVDC converter stations

Parafoudres –
Partie 9: Parafoudres à oxyde métallique sans éclateur pour postes de

conversion CCHT
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XD
ICS 29.120.50; 29.240.10 ISBN 978-2-8322-1644-6

– 2 – IEC 60099-9:2014 © IEC 2014
CONTENTS
FOREWORD . 7
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
4 Typical HVDC converter station schemes, arrester types, locations and operating
voltage . 19
5 Identification and classification . 24
5.1 Arrester identification . 24
5.2 Arrester classification . 25
6 Service conditions . 25
6.1 Normal service conditions . 25
6.2 Abnormal service conditions . 25
7 Requirements . 26
7.1 Insulation withstand of the arrester housing . 26
7.2 Reference voltage . 26
7.3 Residual voltage . 26
7.4 Internal partial discharge . 27
7.5 Seal leak rate. 27
7.6 Current distribution in a multi-column arrester and between matched
arresters . 27
7.7 Long term stability under continuous operating voltage . 27
7.8 Repetitive charge transfer withstand . 27
7.9 Thermal energy capability . 27
7.10 Short-circuit performance . 28
7.11 Requirements on internal grading components . 28
7.12 Mechanical loads . 28
7.12.1 General . 28
7.12.2 Bending moment . 28
7.12.3 Resistance against environmental stresses . 28
7.12.4 Insulating base . 28
7.12.5 Mean value of breaking load (MBL). 29
7.13 Electromagnetic compatibility . 29
7.14 End of life . 29
8 General testing procedure . 29
8.1 Measuring equipment and accuracy . 29
8.2 Reference voltage measurements . 29
8.3 Test samples . 29
8.3.1 General . 29
8.3.2 Arrester section requirements . 30
9 Type tests (design tests) . 31
9.1 General . 31
9.2 Insulation withstand test on the arrester housing . 32
9.2.1 General . 32
9.2.2 Tests on individual unit housings . 32
9.2.3 Tests on complete arrester housing assemblies . 32

9.2.4 Ambient air conditions during tests . 32
9.2.5 Wet test procedure . 33
9.2.6 Lightning impulse voltage test . 33
9.2.7 Switching impulse voltage test . 33
9.2.8 Power-frequency voltage test. 34
9.3 Short-circuit tests . 34
9.4 Internal partial discharge tests . 35
9.5 Test of the bending moment . 36
9.5.1 Test on porcelain-housed arresters . 36
9.5.2 Test on polymer-housed arresters . 37
9.6 Environmental tests . 43
9.6.1 General . 43
9.6.2 Overview . 43
9.6.3 Sample preparation . 44
9.6.4 Test procedure . 44
9.6.5 Test evaluation . 44
9.7 Weather ageing test . 44
9.7.1 General . 44
9.7.2 Test specimens . 44
9.7.3 Test procedure . 44
9.7.4 Evaluation of the test . 45
9.8 Seal leak rate test . 46
9.8.1 General . 46
9.8.2 Overview . 46
9.8.3 Sample preparation . 46
9.8.4 Test procedure . 46
9.8.5 Test evaluation . 46
9.9 Radio interference voltage (RIV) test . 46
9.10 Residual voltage test . 48
9.10.1 General . 48
9.10.2 Steep current impulse residual voltage test . 49
9.10.3 Lightning impulse residual voltage test . 49
9.10.4 Switching impulse residual voltage test . 50
9.11 Test to verify long term stability under continuous operating voltage . 50
9.11.1 General . 50
9.11.2 Test procedure for arresters subjected to voltage reversal . 51
9.11.3 Test procedure for arresters not subjected to voltage reversal . 53
9.12 Test to verify the repetitive charge transfer rating, Q . 54
rs
9.12.1 General . 54
9.12.2 Test procedure . 55
9.12.3 Test evaluation . 55
9.12.4 Rated values of repetitive charge transfer rating, Q . 56
rs
9.13 Heat dissipation behaviour of test sample . 56
9.13.1 General . 56
9.13.2 Arrester section requirements . 56
9.13.3 Procedure to verify thermal equivalency between arrester and arrester
section . 56
9.14 Test to verify the thermal energy rating, W . 57
th
9.14.1 General . 57

– 4 – IEC 60099-9:2014 © IEC 2014
9.14.2 Arrester section requirements . 57
9.14.3 Test procedure . 57
9.15 Test to verify the dielectric withstand of internal components . 58
9.15.1 General . 58
9.15.2 Test procedure . 59
9.15.3 Test evaluation . 59
9.16 Test of internal grading components . 59
9.16.1 Test to verify long term stability under continuous operating voltage . 59
9.16.2 Thermal cyclic test . 60
10 Routine tests and acceptance test . 61
10.1 Routine tests. 61
10.2 Acceptance tests . 62
10.2.1 Standard acceptance tests . 62
10.2.2 Special thermal stability test . 62
11 Test requirements on different types of arresters . 62
11.1 General . 62
11.2 Valve arrester (V) . 62
11.2.1 General . 62
11.2.2 Continuous operating voltage . 62
11.2.3 Equivalent continuous operating voltage . 63
11.2.4 Type tests . 64
11.2.5 Routine and acceptance tests . 65
11.3 Bridge arrester and HV and LV converter unit arresters (B, CH, CL) . 65
11.3.1 Continuous operating voltage . 65
11.3.2 Equivalent continuous operating voltage . 66
11.3.3 Type tests . 66
11.3.4 Routine and acceptance tests . 66
11.4 Converter unit arrester (C) . 66
11.4.1 General . 66
11.4.2 Continuous operating voltage . 66
11.4.3 Equivalent continuous operating voltage . 66
11.4.4 Type tests . 67
11.4.5 Routine and acceptance tests . 67
11.5 Mid-point d.c. bus arrester, mid-point bridge arresters and arrester between
converters (M, MH, ML, CM) . 67
11.5.1 Continuous operating voltage . 67
11.5.2 Equivalent continuous operating voltage . 67
11.5.3 Type tests . 68
11.5.4 Routine and acceptance tests . 68
11.6 Converter unit d.c. bus arrester (CB). 68
11.6.1 Continuous operating voltage . 68
11.6.2 Equivalent continuous operating voltage . 68
11.6.3 Type tests . 69
11.6.4 Routine and acceptance tests . 69
11.7 DC bus and d.c. line/cable arrester (DB, DL/DC) . 69
11.7.1 General . 69
11.7.2 Continuous operating voltage . 69
11.7.3 Equivalent continuous operating voltage . 69
11.7.4 Type tests . 69

11.7.5 Routine and acceptance tests . 70
11.8 Neutral bus arresters (EB, E1, E) . 71
11.8.1 Continuous operating voltage . 71
11.8.2 Equivalent continuous operating voltage . 71
11.8.3 Type tests . 71
11.8.4 Routine and acceptance tests . 72
11.9 DC and AC filter arresters (FA, FD). 72
11.9.1 Continuous operating voltage . 72
11.9.2 Equivalent continuous operating voltage . 72
11.9.3 Type tests . 74
11.9.4 Routine and acceptance tests . 74
11.10 Electrode line and metallic return arresters (EL, EM) . 74
11.10.1 Continuous operating voltage . 74
11.10.2 Equivalent continuous operating voltage . 74
11.10.3 Type tests . 74
11.10.4 Routine and acceptance tests . 74
11.11 Smoothing reactor arrester (DR) . 74
11.11.1 General . 74
11.11.2 Continuous operating voltage . 74
11.11.3 Equivalent continuous operating voltage . 74
11.11.4 Type tests . 74
11.11.5 Routine and acceptance tests . 74
11.12 Capacitor arrester (CC) . 75
11.12.1 General . 75
11.12.2 Continuous operating voltage . 75
11.12.3 Equivalent continuous operating voltage . 75
11.12.4 Type tests . 75
11.12.5 Routine and acceptance tests . 75
11.13 Transformer valve winding arrester (T). 75
11.13.1 General . 75
11.13.2 Continuous operating voltage . 76
11.13.3 Equivalent continuous operating voltage . 76
11.13.4 Type tests . 76
11.13.5 Routine and acceptance tests . 76
Annex A (normative) Test to verify thermal equivalency between complete arrester
and arrester section . 77
Annex B (normative) Determination of the start temperature in the thermal recovery
test . 79
Annex C (normative) Mechanical considerations . 80
C.1 Test of bending moment. 80
C.2 Seismic test . 81
C.3 Definition of mechanical loads . 81
C.4 Definition of seal leak rate . 83
C.5 Calculation of wind-bending-moment. 83
C.6 Procedures of tests of bending moment for porcelain and polymer-housed
arresters . 84
Annex D (informative) Different circuit configurations . 86
Bibliography . 88

– 6 – IEC 60099-9:2014 © IEC 2014
Figure 1 – Single line diagram of typical converter station with two 12-pulse converter
bridges per pole . 20
Figure 2 – Single line diagram of typical converter station with one 12-pulse converter
bridge per pole. 21
Figure 3 – Single line diagram of typical capacitor commutated converter (CCC) pole
with two 12-pulse converters in series. 22
Figure 4 – Typical continuous operating voltages for different arresters – low-
frequency modelling (location as per Figures 1 to 3, fundamental frequency 50 Hz) . 23
Figure 5 – Typical continuous operating voltages for different arresters – high-
frequency modelling (location as per Figures 1 to 3, fundamental frequency 50 Hz) . 24
Figure 6 – Thermomechanical test . 40
Figure 7 – Example of the test arrangement for the thermomechanical test and
direction of the cantilever load . 41
Figure 8 – Water immersion . 42
Figure 9 – Test cycle for accelerated ageing test with polarity reversals, method a) . 52
Figure 10 – Operating voltage of a valve arrester (V) (rectifier operation) and definition
of PCOV and CCOV . 63
Figure 11 – Operating voltage of a bridge arrester and definition of DCOV, PCOV and
CCOV . 65
Figure 12 – Plot showing the relative duration of voltage above certain amplitudes . 73
Figure C.1 – Bending moment – multi-unit surge arrester . 80
Figure C.2 – Definitions of mechanical loads . 82
Figure C.3 – Surge arrester unit . 83
Figure C.4 – Surge-arrester dimensions . 84
Figure C.5 – Flow chart of bending moment test procedures . 85
Figure D.1 – Single line diagram of CSCC converter station with two 12-pulse
converters in series . 86
Figure D.2 – Single line diagram of back-to-back converter station with two 12-pulse
converters in series . 87

Table 1 – Summary of type tests – 1 . 64
Table 2 – Summary of type tests – 2 . 71

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SURGE ARRESTERS –
Part 9: Metal-oxide surge arresters without
gaps for HVDC converter stations

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard 60099-9 has been prepared by IEC technical committee 37: Surge
arresters.
The text of this standard is based on the following documents:
FDIS Report on voting
37/417/FDIS 37/422/RVD
Full information on the voting for the approval of this standard 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.

– 8 – IEC 60099-9:2014 © IEC 2014
A list of all parts in the IEC 60099 series, published under the general title Surge arresters,
can be found on the IEC website.
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.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
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SURGE ARRESTERS –
Part 9: Metal-oxide surge arresters without
gaps for HVDC converter stations

1 Scope
This part of IEC 60099 applies to non-linear metal-oxide resistor type surge arresters without
spark gaps designed to limit overvoltages in HVDC converter stations of two terminal,
multiterminal and back-to-back type up to and including an operating voltage of 1 100 kV. The
standard applies in general to porcelain-housed and polymer-housed type arresters but also
to gas-insulated metal enclosed arresters (GIS-arresters) solely used as d.c. bus and d.c.
line/cable arresters. Arresters for voltage source converters are not covered. Arresters
applied on the a.c. systems at the converter station and subjected to power-frequency voltage
of 50 or 60 Hz principally without harmonics are tested as per IEC 60099-4. The arresters on
a.c.-filters are tested according to this standard.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60060-1, High-voltage test techniques – Part 1: General definitions and test requirements
IEC 60060-2, High-voltage test techniques – Part 2: Measuring systems
IEC 60068-2-11:1981, Environmental testing – Part 2: Tests. Test Ka: Salt mist
IEC 60068-2-14, Environmental testing – Part 2-14: Tests – Test N: Change of temperature
IEC 60068-2-17, Basic environmental testing procedures – Part 2-17: Tests – Test Q: Sealing
IEC 60071-2:1996, Insulation co-ordination – Part 2: Application guide
IEC TS 60071-5:2002, Insulation co-ordination – Part 5: Procedures for high-voltage direct
current (HVDC) converter stations
IEC 60099-4:2004, Surge arresters – Part 4: Metal-oxide surge arresters without gaps for a.c.
systems
IEC 60143-2, Series capacitors for power systems – Part 2: Protective equipment for series
capacitor banks
IEC 60270, High-voltage test techniques – Partial discharge measurements
IEC 60721-3-2, Classification of environmental conditions – Part 3: Classification of groups of
environmental parameters and their severities – Section 2: Transportation
IEC TS 60815-2, Selection and dimensioning of high-voltage insulators intended for use in
polluted conditions – Part 2: Ceramic and glass insulators for a.c. systems

– 10 – IEC 60099-9:2014 © IEC 2014
IEC 62217, Polymeric HV insulators for indoor and outdoor use – General definitions, test
methods and acceptance criteria
IEC 62271-200:2011, High-voltage switchgear and controlgear – Part 200: AC metal-enclosed
switchgear and controlgear for rated voltages above 1 kV and up to and including 52 kV
IEC 62271-203:2011, High-voltage switchgear and controlgear – Part 203: Gas-insulated
metal-enclosed switchgear for rated voltages above 52 kV
CISPR 16-1-1, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1-1: Radio disturbance and immunity measuring apparatus – Measuring
apparatus
CISPR/TR 18-2, Radio interference characteristics of overhead power lines and high-voltage
equipment – Part 2: Methods of measurement and procedure for determining limits
3 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1
acceptance tests
tests made on arresters or representative samples after agreement between manufacturer
and user
3.2
bending moment
force perpendicular to the longitudinal axis of an arrester multiplied by the vertical distance
between the mounting base (lower level of the flange) of the arrester and the point of
application of the force
3.3
breaking load
force perpendicular to the longitudinal axis of a porcelain-housed arrester leading to
mechanical failure of the arrester housing
3.4
continuous current of an arrester
current flowing through the arrester when energized at the continuous operating voltage
Note 1 to entry: The continuous current, which consists of a resistive and a capacitive component, may vary with
temperature, stray capacitance and external pollution effects. The continuous current of a test sample may,
therefore, not be the same as the continuous current of a complete arrester.
Note 2 to entry: The continuous current is, for comparison purposes, expressed either by its r.m.s. or peak value.
3.5
continuous operating voltage of an HVDC-arrester
U
cHVDC
maximum continuous voltage characterized by the voltages CCOV, PCOV and DCOV and the
frequency DFCOV where applicable and that may be applied continuously between the
arrester terminals
3.6
coordination current of an arrester
for a given system under study and for each class of overvoltage, the current through the
arrester for which the representative overvoltage is determined

Note 1 to entry: Standard shapes of coordination currents for steep-front, lightning and switching current impulses
are given in IEC 60099-4.
Note 2 to entry: The coordination currents are determined by system studies.
3.7
crest value of continuous operating voltage
CCOV
highest continuously occurring crest value of the voltage across the arrester excluding
commutation overshoots and commutation notches and calculated with a system model valid
for up to approximately 5 kHz
Note 1 to entry: As an example, see Figure 10, given for valve arresters.
3.8
damage limit (mechanical)
lowest value of a force perpendicular to the longitudinal axis of a polymer-housed arrester
leading to mechanical failure of the arrester housing
3.9
d.c. component of the continuous operating voltage
DCOV
highest mean or average of the continuous operating voltage, U ,across the
cHVDC
arrester,excluding harmonics and commutation overshoots
Note 1 to entry: As an example, see Figure 11, given for bridge arrester.
3.10
d.c. system voltage
highest mean or average operating voltage to earth, excluding harmonics and commutation
overshoots
3.11
designation of an impulse shape
combination of two numbers, the first representing the virtual front time (T ) and the second
the virtual time to half-value on the tail (T )
Note 1 to entry: It is written as T /T , both in microseconds, the sign "/ " having no mathematical meaning.
1 2
3.12
discharge current of an arrester
impulse current which flows through the arrester
3.13
disruptive discharge
phenomenon associated with the failure of insulation under electric stress, which includes a
collapse of voltage and the passage of current
Note 1 to entry: The term applies to electrical breakdowns in solid, liquid and gaseous dielectric, and
combinations of these.
Note 2 to entry: A disruptive discharge in a solid dielectric produces permanent loss of electric strength. In a
liquid or gaseous dielectric the loss may be only temp
...