Rotating electrical machines - Part 18-42: Qualification and acceptance tests for partial discharge resistant electrical insulation systems (Type II) used in rotating electrical machines fed from voltage converters (IEC/TS 60034-18-42:2008)

This Technical Specification defines criteria for assessing the insulation system of stator/rotor windings which are subjected to pulse width modulation (PWM) drives and expected to withstand partial discharge activity during service. This Technical Specification applies to stator/rotor windings of single or polyphase AC machines with insulation systems for converter operation.

Drehende elektrische Maschinen - Teil 18-42: Qualifizierungs- und Abnahmeprüfungen teilentladungsresistenter Isoliersysteme (Typ II) von drehenden elektrischen Maschinen, die von Spannungsumrichtern gespeist werden (IEC/TS 60034-18-42:2008)

Machines électriques tournantes - Partie 18-42: Essais de qualification et d'acceptation des systèmes d'isolation électrique résistants aux décharges partielles (Type II) utilisés dans des machines électriques tournantes alimentées par convertisseurs de tension (IEC/TS 60034-18-42:2008)

La CEI/TS 60034-18-42:2008 définit les critères d'évaluation du système d'isolation des enroulements statorique et rotorique des machines à courant alternatif monophasées ou polyphasées qui sont soumises à des tensions de choc répétitives, comme par exemple les convertisseurs à modulation de largeur d'impulsion, et susceptibles d'endurer des décharges partielles pendant leur fonctionnement. Elle spécifie des essais de qualification électrique et d'acceptation réalisés sur des échantillons représentatifs, en vue de vérifier leur adéquation à un fonctionnement avec des convertisseurs de source de tension.

Električni rotacijski stroji - 18-42. del: Kvalifikacijsko in prevzemno preskušanje električnih izolacijskih sistemov, odpornih proti delni izpraznitvi (tip II), ki se uporabljajo v električnih rotacijskih strojih, napajanih prek napetostnih pretvornikov (IEC/TS 60034-18-42:2008)

Ta tehnična specifikacija določa kriterije za ocenjevanje izolacijskega sistema navitij stator/rotor, ki so izpostavljena pogonom z modulacijo širine pulza (PWM) in za katere se pričakuje, da zdržijo aktivnost delne izpraznitve med storitvijo. Ta tehnična specifikacija velja za navitja enofaznih ali polifaznih strojev stator/rotor z izmeničnim tokom z izolacijskimi sistemi za delovanje pretvornika.

General Information

Status
Withdrawn
Publication Date
03-Mar-2011
Withdrawal Date
10-Dec-2019
Technical Committee
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
11-Dec-2019
Due Date
03-Jan-2020
Completion Date
11-Dec-2019

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SLOVENSKI STANDARD
SIST-TS CLC/TS 60034-18-42:2011
01-april-2011
(OHNWULþQLURWDFLMVNLVWURMLGHO.YDOLILNDFLMVNRLQSUHY]HPQRSUHVNXãDQMH
HOHNWULþQLKL]RODFLMVNLKVLVWHPRYRGSRUQLKSURWLGHOQLL]SUD]QLWYL WLS,, NLVH
XSRUDEOMDMRYHOHNWULþQLKURWDFLMVNLKVWURMLKQDSDMDQLKSUHNQDSHWRVWQLK
SUHWYRUQLNRY ,(&76
Rotating electrical machines - Part 18-42: Qualification and acceptance tests for partial
discharge resistant electrical insulation systems (Type II) used in rotating electrical
machines fed from voltage converters (IEC/TS 60034-18-42:2008)
Drehende elektrische Maschinen - Teil 18-42: Qualifizierungs- und Abnahmeprüfungen
teilentladungsresistenter Isoliersysteme (Typ II) von drehenden elektrischen Maschinen,
die von Spannungsumrichtern gespeist werden (IEC/TS 60034-18-42:2008)
Machines électriques tournantes - Partie 18-42: Essais de qualification et d'acceptation
des systèmes d'isolation électrique résistants aux décharges partielles (Type II) utilisés
dans des machines électriques tournantes alimentées par convertisseurs de tension
(IEC/TS 60034-18-42:2008)
Ta slovenski standard je istoveten z: CLC/TS 60034-18-42:2011
ICS:
29.080.30 Izolacijski sistemi Insulation systems
29.160.01 Rotacijski stroji na splošno Rotating machinery in
general
SIST-TS CLC/TS 60034-18-42:2011 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST-TS CLC/TS 60034-18-42:2011

---------------------- Page: 2 ----------------------

SIST-TS CLC/TS 60034-18-42:2011

TECHNICAL SPECIFICATION
CLC/TS 60034-18-42

SPÉCIFICATION TECHNIQUE
February 2011
TECHNISCHE SPEZIFIKATION

ICS 29.160


English version


Rotating electrical machines -
Part 18-42: Qualification and acceptance tests for partial discharge
resistant electrical insulation systems (Type II) used in rotating electrical
machines fed from voltage converters
(IEC/TS 60034-18-42:2008)


Machines électriques tournantes -  Drehende elektrische Maschinen -
Partie 18-42: Essais de qualification et Teil 18-42: Qualifizierungs- und
d'acceptation des systèmes d'isolation Abnahmeprüfungen
électrique résistants aux décharges teilentladungsresistenter Isoliersysteme
partielles (Type II) utilisés dans des (Typ II) von drehenden elektrischen
machines électriques tournantes Maschinen, die von Spannungsumrichtern
alimentées par convertisseurs de tension gespeist werden
(CEI/TS 60034-18-42:2008) (IEC/TS 60034-18-42:2008)





This Technical Specification was approved by CENELEC on 2011-01-25.

CENELEC members are required to announce the existence of this TS in the same way as for an EN and to
make the TS available promptly at national level in an appropriate form. It is permissible to keep conflicting
national standards in force.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.



CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels


© 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. CLC/TS 60034-18-42:2011 E

---------------------- Page: 3 ----------------------

SIST-TS CLC/TS 60034-18-42:2011
CLC/TS 60034-18-42:2011 - 2 -
Foreword
The text of the Technical Specification IEC/TS 60034-18-42:2008, prepared by IEC TC 2, Rotating
machinery, was submitted to the formal vote and was approved by CENELEC as CLC/TS 60034-18-42
on 2011-01-25.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following date was fixed:
– latest date by which the existence of the CLC/TS
has to be announced at national level (doa) 2011-07-25
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the Technical Specification IEC/TS 60034-18-42:2008 was approved by CENELEC as a
Technical Specification without any modification.

---------------------- Page: 4 ----------------------

SIST-TS CLC/TS 60034-18-42:2011
- 3 - CLC/TS 60034-18-42:2011
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

IEC 60034-18-1 - Rotating electrical machines - EN 60034-18-1 -
Part 18-1: Functional evaluation of insulation
systems - General guidelines


IEC 60034-18-32 - Rotating electrical machines - EN 60034-18-32 -
Part 18-32: Functional evaluation of insulation
systems - Test procedures for form-wound
windings - Evaluation of electrical endurance


IEC/TS 60034-18-41 - Rotating electrical machines - - -
Part 18-41: Qualification and type tests for
Type I electrical insulation systems used in
rotating electrical machines fed from voltage
converters


IEC 60216-3 - Electrical insulating materials - Thermal EN 60216-3 -
endurance properties -
Part 3: Instructions for calculating thermal
endurance characteristics


IEC/TS 61251 - Electrical insulating materials - A.C. voltage - -
endurance evaluation - Introduction


IEC 61800-4 - Adjustable speed electrical power drive EN 61800-4 -
systems -
Part 4: General requirements - Rating
specifications for a.c. power drive systems
above 1 000 V a.c. and not exceeding 35 kV


IEC 62068-1 - Electrical insulation systems - Electrical EN 62068-1 -
stresses produced by repetitive impulses -
Part 1: General method of evaluation of
electrical endurance


IEC 62539 - Guide for the statistical analysis of electrical - -
insulation breakdown data

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SIST-TS CLC/TS 60034-18-42:2011

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SIST-TS CLC/TS 60034-18-42:2011
IEC/TS 60034-18-42
Edition 1.0 2008-08
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Rotating electrical machines –
Part 18-42: Qualification and acceptance tests for partial discharge resistant
electrical insulation systems (Type II) used in rotating electrical machines fed
from voltage converters

Machines électriques tournantes –
Partie 18-42: Essais de qualification et d’acceptation des systèmes d’isolation
électrique résistants aux décharges partielles (Type II) utilisés dans des
machines électriques tournantes alimentées par convertisseurs de tension

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
V
CODE PRIX
ICS 29.160 ISBN 2-8318-9966-4
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 7 ----------------------

SIST-TS CLC/TS 60034-18-42:2011
– 2 – TS 60034-18-42 © IEC:2008
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references .7
3 Terms and definitions .8
4 Voltage effects from converter operation .10
4.1 Voltages at the terminals of the converter-fed machine .10
4.2 Electrical stresses in the insulation system of machine windings .13
4.2.1 General .13
4.2.2 Voltages stressing the phase/phase insulation.14
4.2.3 Voltages stressing the phase/ground insulation .14
4.2.4 Voltages stressing the turn insulation .14
5 Type II insulation systems .14
6 Stress factors for converter-fed Type II insulation systems .15
7 Qualification and acceptance tests .16
7.1 General .16
7.2 Qualification tests.16
7.3 Acceptance test.17
8 Qualification of turn insulation .17
8.1 General .17
8.2 Test methods .17
9 Qualification of ground wall insulation systems.19
9.1 General .19
9.2 Test methods .19
9.3 Use of 50 Hz or 60 Hz life data to predict the service life with a converter
drive.20
10 Qualification of the stress control and corona protection system.21
10.1 General .21
10.2 Test methods .22
11 Preparation of test objects.23
11.1 General .23
11.2 Turn/turn samples .23
11.3 Coils.24
12 Qualification test procedures .24
12.1 General .24
12.2 Turn/turn samples .24
12.3 Coils.24
12.4 Stress control samples .25
13 Qualification test pass criteria .25
13.1 Turn/turn samples .25
13.2 Coil samples .25
13.3 Stress control samples .26
14 Acceptance test for Type II insulation systems (Type test).26
14.1 General .26
14.2 Acceptance test methods .26

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SIST-TS CLC/TS 60034-18-42:2011
TS 60034-18-42 © IEC:2008 – 3 –
14.3 Acceptance test pass criteria.26
15 Analysis, reporting and classification .26
Annex A (informative) .27
Annex B (informative) .29
Annex C (informative) .31
Figure 1 – Voltage impulse waveshape parameters .10
Figure 2 – Phase/phase voltage at the terminals of a machine fed by a 3-level
converter .11
Figure 3 – Possible jump voltages (U ) at the machine terminals associated with a
j
converter drive.12
Figure 4 – Maximum voltage enhancement at the machine terminals as a function of
cable length for various impulse rise times for a 2-level converter.13
Figure 5 – Design examples.14
Figure 6 – Life lines of turn and mainwall insulation. .18
Figure 7 – Example of a life curve for a Type II mainwall insulation system.21
Figure 8 – Example of the construction of a turn/turn test sample for rectangular
conductors.23
Figure A.1 – Example of a simple converter voltage simulation circuit.27
Figure A.2 – Typical waveform generated from the spark gap oscillator .28
Figure B.1 – Representation of the phase to ground voltage at the terminals of a
machine fed from a 3-level converter .29
Table 1 – Influence of features of the converter drive voltage on acceleration of ageing
of components of Type II insulation systems.15
Table B.1 – Contribution to electrical ageing by 1 kHz impulses from a 3-level
converter as a percentage of the ageing from the 50 Hz fundamental voltage for
various values of voltage endurance coefficient (n).30

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SIST-TS CLC/TS 60034-18-42:2011
– 4 – TS 60034-18-42 © IEC:2008
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –
Part 18-42: Qualification and acceptance tests for partial
discharge resistant electrical insulation systems (Type II) used
in rotating electrical machines fed from voltage converters
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
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.
The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC 60034-18-42, which is a Technical Specification, has been prepared by IEC technical
committee 2: Rotating machinery.

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SIST-TS CLC/TS 60034-18-42:2011
TS 60034-18-42 © IEC:2008 – 5 –
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
2/1482/DTS 2/1502/RVC
Full information on the voting for the approval of this technical specification 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.
A list of all parts of IEC 60034 series, under the general title Rotating electrical machines, can
be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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SIST-TS CLC/TS 60034-18-42:2011
– 6 – TS 60034-18-42 © IEC:2008
INTRODUCTION
The approval of electrical insulation systems for use in rotating electrical machines driven
from voltage converters is set out in two Technical Specifications. They separate the systems
into those which are not expected to experience partial discharge activity within specified
conditions in their service lives (Type I) and those which are expected to withstand partial
discharge activity in any part of the insulation system throughout their service lives (Type II).
For both Type I and Type II insulation systems, the drive system integrator should inform the
machine manufacturer what voltage will appear at the machine terminals in service. The
machine manufacturer will then decide upon the severity of the tests appropriate for qualifying
the insulation system. The severity is based on the impulse rise time, the peak to peak
voltage and, in the case of Type II systems, the impulse repetition rate.
IEC/TS 60034-18-41
Type I insulation systems are dealt with in IEC/TS 60034-18-41. They are generally used in
rotating machines rated at less than 700 V r.m.s. and tend to have random wound stators. In
this Technical Specification, the necessary normative references and definitions are given
together with a review of the effects arising from converter operation. Having established the
technical foundation for the evaluation procedure, the conceptual approach is then described.
IEC/TS 60034-18-42
In this Technical Specification, the tests for qualification and acceptance of electrical
insulation systems chosen for Type II rotating electrical machines are described. These
insulation systems are generally used in rotating machines and tend to have form-wound
coils, mostly rated above 700 V r.m.s. The qualification procedure is completely different from
that used for Type I insulation systems and involves destructive ageing of insulated test
objects under accelerated conditions. The manufacturer requires a life curve for the insulation
system that can be interpreted to provide an estimate of life under the service conditions with
converter drive. Great importance is attached to the qualification of any stress grading system
that is used and testing here should be performed under repetitive impulse conditions. If the
insulation system can be shown to provide an acceptable life under the appropriate ageing
conditions, it is qualified for use. Acceptance testing is performed on coils made using this
insulation system when subjected to a voltage endurance test.
This Technical Specification should be read in conjunction with IEC/TS 60034-18-41, which
provides a background to the technology of converter drive/machine systems.
The winding insulation systems intended for converter-fed machines and converter
technologies are evolving rapidly. In addition, there is on-going research into the best ways to
test such insulation systems. It is expected therefore that there will be improvements in these
Technical Specifications over the next few years.

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SIST-TS CLC/TS 60034-18-42:2011
TS 60034-18-42 © IEC:2008 – 7 –
ROTATING ELECTRICAL MACHINES –
Part 18-42: Qualification and acceptance tests for partial
discharge resistant electrical insulation systems (Type II) used
in rotating electrical machines fed from voltage converters
1 Scope
This Technical Specification defines criteria for assessing the insulation system of stator/rotor
windings of single or polyphase AC machines which are subjected to repetitive impulse
voltages, such as pulse width modulation (PWM) converters, and expected to withstand
partial discharge activity during service. It specifies electrical qualification and acceptance
tests on representative samples which verify fitness for operation with voltage-source
converters.
This document does not apply to:
– Rotating machines which are fed by converters only for starting.
– Electrical equipment and systems for traction.
NOTE Although this Technical Specification deals with voltage-source converters, it is recognised that there are
other types of converters that can create repetitive impulse voltages. For these converters, a similar approach to
testing can be used if needed.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60034-18-1, Rotating electrical machines – Functional evaluation of insulation systems –
Part 18-1: General guidelines
IEC 60034-18-32, Rotating electrical machines – Functional evaluation of insulation systems –
Part 18-32: Test Procedures for form-wound windings – Electrical evaluation of insulation
systems used in machines up to and including 50 MVA and 15 kV
IEC/TS 60034-18-41, Rotating electrical machines – Part 18-41: Qualification and type tests
for Type I electrical insulation systems used in rotating electrical machines when fed from
voltage converters
IEC 60216-3, Electrical insulating materials – Thermal endurance properties – Part 3:

Instructions for calculating thermal endurance characteristics
IEC/TS 61251, Electrical insulating materials – A.C. voltage endurance evaluation –
Introduction
IEC 61800-4, Adjustable speed electrical power drive systems – Part 4: General requirements
– Rating specifications for a.c. power drive systems above 1 000 V a.c. and not exceeding
35 kV
IEC 62068-1, Electrical insulating systems – Electrical stresses produced by repetitive
impulses – Part 1: General method of evaluation of electrical endurance

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SIST-TS CLC/TS 60034-18-42:2011
– 8 – TS 60034-18-42 © IEC:2008
IEC 62539, Guide for the statistical analysis of electrical insulation breakdown data
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
voltage endurance coefficient
symbol: n
exponent of the inverse power model or exponential model on which the relationship between
life and stressing voltage amplitude for a specific insulation system depends
3.2
life
time to failure
3.3
stress grading material
material generally having a non-linear resistivity characteristic, applied to the endwindings of
stators to reduce the maximum surface electrical stress
3.4
corona protection material
material which is used to coat a stator bar within the slot portion of the stator core to avoid
slot discharges
3.5
impulse rise time
symbol: t
r
time for the voltage impulse to go from 0 % to 100 % (See Figure 1)
NOTE Unless otherwise stated, it is estimated as 1,25 times the time for the voltage to rise from 10 % to 90 %.
3.6
electrical insulation system
insulating structure containing one or more electrical insulating materials together with
associated conducting parts employed in an electrotechnical device
[IEC 62068-1]
3.7
(electric) stress
electric field in V/mm
3.8
rated voltage
symbol: U
N
voltage assigned, generally by the manufacturer, for a specified operating condition of a
machine
3.9
fundamental frequency
first frequency, in the spectrum obtained from a Fourier transform of a periodic time function,
to which all the frequencies of the spectrum are referred
NOTE For the purposes of this Technical Specification, the fundamental frequency of the machine terminal
voltage is the one defining the speed of the converter-fed machine.

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SIST-TS CLC/TS 60034-18-42:2011
TS 60034-18-42 © IEC:2008 – 9 –
3.10
steady state voltage impulse magnitude
symbol: U
a
final magnitude of the voltage impulse (see Figure 1)
3.11
peak (impulse) voltage
symbol: U
p
maximum numerical value of voltage reached during a unipolar voltage impulse (e.g. U in
p
Figure 1)
NOTE 1 For bi-polar voltage impulses, it is half the peak to peak voltage (See Figure 2).
NOTE 2 The peak to peak voltage, Upk/pk is shown in Figure 2.
3.12
voltage overshoot
symbol: U
b
magnitude of the peak voltage in excess of the steady state impulse voltage (see Figure 1)
3.13
impulse repetition frequency
average number of voltage
...

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