EN 50533:2011
(Main)Railway applications - Three-phase train line voltage characteristics
Railway applications - Three-phase train line voltage characteristics
This European Standard describes the electrical characteristics of the three-phase train line which delivers the electrical energy from the auxiliary power converter system to the auxiliary loads. It applies to: o locomotive hauled passenger trains, o electric multiple units, o diesel electric multiple units. This European Standard may apply to other rolling stock types (e.g. light rail vehicles, tramways, metros, etc.) if they are not in the scope of another specific standard.
Bahnanwendungen - Eigenschaften der dreiphasigen (Drehstrom-) Bordnetz-Spannung
Applications ferroviaires - Caractéristiques de la tension de la ligne de train triphasée
Železniške naprave - Napetostne karakteristike trifaznega glavnega voda na tirnem vozilu
Ta evropski standard opisuje električne karakteristike trifaznega glavnega voda na tirnem vozilu, ki prenaša električno energijo iz pomožnega sistema za pretvorbo energije do pomožnih obremenitev. Uporablja se za: – potniške vlake, ki jih vleče lokomotiva; – električne večdelne enote; – dizelske električne večdelne enote. Ta evropski standard se lahko uporablja za druge vrste železniških vozil (npr. lahka železniška vozila, tramvaje, metroje itn.), če jih ne obravnava drug specifičen standard.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 50533:2012
01-februar-2012
Železniške naprave - Napetostne karakteristike trifaznega glavnega voda na tirnem
vozilu
Railway applications - Three-phase train line voltage characteristics
Bahnanwendungen - Eigenschaften der dreiphasigen (Drehstrom-) Bordnetz-Spannung
Applications ferroviaires - Caractéristiques de la tension de la ligne de train triphasée
Ta slovenski standard je istoveten z: EN 50533:2011
ICS:
29.280 (OHNWULþQDYOHþQDRSUHPD Electric traction equipment
45.060.01 Železniška vozila na splošno Railway rolling stock in
general
SIST EN 50533:2012 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 50533:2012
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SIST EN 50533:2012
EUROPEAN STANDARD
EN 50533
NORME EUROPÉENNE
November 2011
EUROPÄISCHE NORM
ICS 29.280; 45.060.01
English version
Railway applications -
Three-phase train line voltage characteristics
Applications ferroviaires - Bahnanwendungen -
Caractéristiques de la tension de la ligne Eigenschaften der dreiphasigen
de train triphasée (Drehstrom-) Bordnetz-Spannung
This European Standard was approved by CENELEC on 2011-10-10. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
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 European Standard 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, 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. EN 50533:2011 E
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EN 50533:2011 – 2 –
Contents
Foreword . 4
Introduction . 5
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviations . 8
3.1 Terms and definitions . 8
3.2 Abbreviations .10
4 Characteristics of the three-phase train line voltage .11
4.1 General .11
4.2 Frequenc y .11
4.3 Voltage amplitude .12
4.4 Voltage harmonics .13
4.5 Voltage unbalance .13
4.6 Train line voltage amplitude and rate of rise .14
4.7 Transient overvoltage .16
4.8 Dynamic characteristics – Voltage dips – Supply interruption .16
4.9 Train line additional data (informative) .20
5 Shore supply .20
5.1 General .20
5.2 Shore supply voltage characteristics .21
5.3 Shore supply general features .21
Annex A (informative) Train line supply architectures .22
A.1 General-Train line supply classes .22
A.2 Class 1 - Galvanic isolation at auxiliary converter output side and sine filter .22
A.3 Class 1 - Galvanic isolation at auxiliary converter input side and sine filter .23
A.4 Class 2 and Class 3 - Train line supply without galvanic isolation .24
Bibliography .26
Figures
Figure 1 – The different voltages of the three-phase train line system . 11
Figure 2 Static voltage tolerances along the train line . 13
Figure 3 Voltage rise time- dU/dt definition. 16
Figure 4 Train line voltage start-up . 17
Figure 5 Voltage fluctuation tolerances . 18
Figure 6 – Current limitation . 20
Figure A.1 Train line supply architecture with galvanic isolation at auxiliary converter output side . 23
Figure A.2 Train line supply architecture with galvanic isolation at auxiliary converter input side . 24
Figure A.3 Train line supply architecture without galvanic isolation . 25
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Tables
Table 1 Frequency . 12
Table 2 – Voltage amplitude . 12
Table 3 Voltage harmonics . 13
Table 4 Current and voltage unbalances . 14
Table 5 Train line voltage amplitude and rate of rise- dU/dt . 15
Table 6 Transient overvoltage . 16
Table 7 - 3-AC voltage start-up . 16
Table 8 Voltage fluctuations . 17
Table 9 Overload and interruptions . 19
Table 10 Informative data about 3-AC voltages . 20
Table 11 Train line supply classes . 22
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EN 50533:2011 – 4 –
Foreword
This document (EN 50533:2011) has been prepared by Working Group 18 of SC 9XB,
"Electromechanical material on board rolling stock", of Technical Committee CENELEC TC 9X,
"Electrical and electronic applications for railways".
The following dates are fixed:
• latest date by which this document has to be
(dop) 2012-10-10
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national standards
(dow) 2014-10-10
conflicting with this
document have to be withdrawn
This standardization project was derived from the EU-funded Research project MODTRAIN
(MODPOWER). It is part of a series of standards, referring to each other. The hierarchy of the
standards is intended to be as follows:
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.
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Introduction
This European Standard defines the characteristics of the on board three-phase train line which
delivers the electrical energy to the auxiliary power system. The following European Standards and
Technical Specifications refer to the defined target energy supply system in this European Standard:
CLC/TS 50534 Railway applications – Generic system architectures for onboard electric
auxiliary power systems
CLC/TS 50535 Railway applications – Onboard auxiliary power converter systems
Auxiliary converter interfaces applicable for the different options defined in
the target system architectures.
CLC/TS 50537 (series) Railway applications – Mounted parts of the traction transformer and
cooling system
Standardized products used in conjunction with traction transformers and
traction cooling systems.
1)
EN 50546 Railway applications – Shore (external) supply system for rail vehicles
Interface description of the shore supply including protection functions.
1
)
EN 50547 Railway applications – Batteries for rail vehicles
Standardized batteries for rail vehicles and charging characteristics.
The three-phase voltage characteristics depend on the performances of the auxiliary converters which
supply the train line but also on the AC load characteristics connected to this train line. In railway
applications the available auxiliary power of the train line is generally slightly higher than the power
needed by the consumer loads, consequently tight interactions between the auxiliary power converter
system and the loads are common and have to be taken into consideration for a proper operation at
train system level.
The main objective followed by this European Standard is to define as much as possible the static
characteristics and the dynamic behaviour of the on-board three-phase supply network to assure the
best electrical compatibility with the AC loads connected to.
This European Standard is a guideline for specifying and designing the different parts of the auxiliary
power supply system namely the different auxiliary converters and the AC loads (i.e. 3 AC motors,
converters, filters, transformers, etc.) connected to the grid.
Some specific characteristics of the train line voltage may impact the reliability and the life time of the
AC loads if they are not taken into consideration during the design phase of the AC loads.
The three-phase train line voltages are never perfectly balanced and pure sinusoidal waveform
voltages, as examples:
———————
1) Under development.
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EN 50533:2011 – 6 –
o the switching of the semi-conductors within the static auxiliary converters may
generate voltage harmonics and dU/dt steps on the train line;
o the line-to-earth voltage level can vary with the auxiliary supply architecture and the
type of faults in the train line;
o a common mode voltage can appear to the star point of the 3 AC loads;
o the non linear AC loads can be a source of current harmonics, those currents
combined with the train line impedance create voltage harmonics too (mainly the input
rectifiers of certain AC loads).
In summary:
o voltage harmonics can generate noise, additional Joule or iron losses in auxiliary
motors and transformers;
o high dU/dt and the common mode voltage are at the origin of motor bearing currents
which may lead to a reduced bearing lifetime;
o voltage spikes and overvoltages may cause an early ageing of the winding insulation
materials.
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1 Scope
This European Standard describes the electrical characteristics of the three-phase train line which
delivers the electrical energy from the auxiliary power converter system to the auxiliary loads.
It applies to:
o locomotive hauled passenger trains,
o electric multiple units,
o diesel electric multiple units.
This European Standard may apply to other rolling stock types (e.g. light rail vehicles, tramways,
metros, etc.) if they are not in the scope of another specific standard.
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.
EN 50160:2007 Voltage characteristics of electricity supplied by public distribution
networks
2)
EN 50546 Railway applications – Shore (external) supply system for rail vehicles
EN 60034-26:2006 Rotating electrical machines – Part 26: Effects of unbalanced voltages on
the performance of three-phase cage induction motors
(IEC 60034-26:2006)
EN 60077-1:2002
Railway applications – Electric equipment for rolling stock – Part 1:
General service conditions and general rules (IEC 60077-1:1999, mod.)
EN 60146-2:2000 Semiconductor converters – Part 2: Self-commutated semiconductor
converters including direct d.c. converters (IEC 60146-2:1999)
EN 61000-2-2:2002 Electromagnetic compatibility (EMC) – Part 2-2: Environment –
Compatibility levels for low-frequency conducted disturbances and
signalling in public low-voltage power supply systems
(IEC 61000-2-2:2002)
IEC/TS 60034-17:2006 Rotating electrical machines – Part 17: Cage induction motors when fed
from converters – Application guide
IEC 60038:2009 IEC standard voltages
UIC 554-1:1979 Power supply to electrical equipment on stationary railway vehicles from a
local mains system or another source of energy at 220 V or 380 V, 50 Hz
———————
2) Under development.
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3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1 three-phase train line
typically a 3-wire or 3-wire and neutral wire line which distributes all along the train the three-phase
electrical energy to the auxiliary loads, namely the loads dedicated to the traction systems and the
loads for passenger comfort
3.1.2 fundamental frequency
frequency in the spectrum obtained from a Fourier transform of a time function, to which all the
frequencies of the spectrum are referred
For the purpose of this European Standard, the fundamental frequency is the one delivered by the
auxiliary converters installed on board.
3.1.3 harmonic frequency
frequency which is an integer multiple of the fundamental frequency
3.1.4
harmonic component
component having a harmonic frequency. Its value is normally expressed as an r.m.s. value
3.1.5 interharmonic frequency
frequency which is not an integer multiple of the fundamental frequency, e.g. the switching frequency
of the auxiliary converters and all the associated harmonics which are not multiple of the fundamental
frequency
3.1.6 interharmonic component
component having an interharmonic frequency. Its value is normally expressed as an r.m.s. value
3.1.7 harmonic order
ratio of the harmonic to the fundamental frequency is the harmonic order
3.1.8 total harmonic distortion (THD)
ratio of the r.m.s. value of the sum of all the harmonic components up to a specified order to the r.m.s.
value of the fundamental component:
h=40
2
U
∑ h
h=2
THD=
2
U
1
where
U is the r.m.s. value of the fundamental voltage component;
1
h is the harmonic order;
U is the r.m.s. value of the harmonic voltage component of order h
h
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3.1.9 total distortion content (TDC)
quantity remaining when the fundamental component is subtracted from an alternating quantity, all
being treated as functions of time
2 2
TDC = Q − Q
1
where
Q is the r.m.s. value of the fundamental component;
1
Q is the total r.m.s. value;
Q can represent either current or voltage. It includes both harmonic and interharmonic
components.
In this European Standard TDC refers to the line voltages, that is:
2 2
TDC = U −U
1
where
U is the r.m.s. value of the fundamental voltage component;
1
U is the total r.m.s. value of voltage
3.1.10 total distortion ratio (TDR)
ratio of the r.m.s. value of the total distortion content of an alternating quantity to the r.m.s. value of the
fundamental component of the quantity:
2 2
Q − Q
TDC
1
TDR= =
Q Q
1 1
In this European Standard TDR refers to the line voltages, that is:
2 2
U −U
TDC
1
TDR= =
U U
1 1
3.1.11 voltage unbalance
condition in a three-phase system in which the r.m.s. values of the line-to-line voltages (fundamental
component), or the phase angle between consecutive line-to-line voltages, are not all equal. The
degree of the inequality is usually expressed as the ratios of the negative sequence (U ) and the zero
2
sequence (U ) components to the positive sequence component (U ):
0 1
1
U =()U + U +U
0 12 23 31
3
1
2
U =()U + a.U + a .U
1 12 23 31
3
1
2
U =()U + a .U + a .U
2 12 23 31
3
U , U , U formula according to the Fortescue transformation
o 1 2
where
U U U are the line-to-line voltages;
12, 23, 31
2π
j
3
a phasor 120° a= e ;
4π
j
2
3
a phasor 240° a= e
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EN 50533:2011 – 10 –
3.1.12 on board auxiliary power converter system
onboard subsystem which transforms electrical energy for traction auxiliary loads and comfort loads
3.1.13 linear loads
loads with a linear dependency between supply voltage and current. Additionally, loads producing
negligible harmonic content compared to rated values are also regarded as linear loads in this
European Standard, e.g. heating resistors, induction motors
3.1.14 non-linear loads
in contrast to linear loads, non-linear loads generate significant harmonic current or voltage content.
These kinds of loads connected to a supply system with significant internal impedance will produce
significant harmonic voltages, e.g. uncontrolled rectifiers and active front-end converters belong to this
load group
3.1.15 unbalanced loads
loads which will cause unsymmetrical phase currents, i.e. currents that have different amplitudes
and / or phase angles in the three phases of a 3 AC supply system. Single phase loads connected to a
3 AC system are a representative example of unbalanced loads
3.1.16 common mode voltage (U )
CM
commonly defined as the arithmetic mean of the line-to-earth voltages, U = 1/3 (U + U + U )
CM L1-E L2-E L3-E
3.2 Abbreviations
For the purposes of this document, the following abbreviations apply.
AC Alternating current
3 AC Three-phase Alternating Current
DC Direct Current
E Earth (or ground)
EDM Electrostatic Discharge Machining
EMC Electro-Magnetic Compatibility
L-E Line-to-Earth
L-L Line-to-Line
L-N Line-to-Neutral
N Neutral
r.m.s. Root Mean Square
TDC Total Distortion Content
TDR
Total Distortion Ratio
THD Total Harmonic Distortion
U
Common Mode Voltage at star point
CM
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4 Characteristics of the three-phase train line voltage
4.1 General
The characteristics of the three-phase train line are defined at the consumer side.
Figure 1 defines all the signals around a “Y” or “star” connected three-phase load taken as an
example. It should be noted that all the signals have to be considered, not only the line-to-line voltages
across the load terminals but also the voltages between lines (L1, L2, L3) and earth or between the
star point and earth. In this case “earth” is referenced to the carbody potential.
The star-point-to-earth voltage, here U is identical to the common mode voltage U .
0-Earth, CM
These definitions are used in the tables below:
ThrThreee-e-phphasase Loe Loadad
WiWirree L L11
UU
LiLine-ne-LLiinnee
StStarar po poiinntt 00
WiWirree L L22
WiWirree L L33
UU
LiLine-Nne-Neeuuttralral
WiWirree N N
NN
UU UU = U= U
NNeutraleutral--EEaartrthh 0-E0-Eaartrth h CMCM
UU
LiLine-Ene-Eaarrtthh
EE
EaEarrtthh
Figure 1 – The different voltages of the three-phase train line system
4.2 Frequency
The characteristics of the fundamental frequency of the train line are defined in Table 1. Two standard
frequencies are possible 50 Hz or 60 Hz. The frequency variations are in line with the existing EN or
IEC standards for non synchronized networks.
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Table 1 Frequency
Parameter Name Unit Description Value
Nominal frequency F Hz Fundamental frequency delivered 50 Hz or 60 Hz
1
by the auxiliary converters
Frequency tolerance % F % Variations of the fundamental
± 2 %
1
frequency F
1
(In accordance with
EN 61000-2-2:2002, 4.8, and to
EN 50160:2007, 4.1)
4.3 Voltage amplitude
Voltage amplitude and variations of the train line are given by Table 2. Two different line-to-line
amplitudes are recommended depending on the fundamental frequency 50 Hz or 60 Hz. In case of
neutral, only one set of amplitude and frequency is recommended.
The static tolerances for the train line voltages are given at the far end of the train line (at load side).
The voltage drop along the line has to be taken into consideration, that is why the voltage tolerances
are tighter at auxiliary converter side with only –5 %. Figure 2 shows the different voltage tolerances at
different locations on the train line with –5 % near the auxiliary converter outputs and –10 % at the end
of the train line. If a transformer is used between the train line and specific loads, an additional voltage
drop is considered (the tolerance becomes -14 %).
Table 2 – Voltage amplitude
Parameter Name Unit Description Value
Nominal line-to-line U V r.m.s. line-to-line voltage at the 400 V at 50 Hz
1-L-L
voltage fundamental frequency F
1
or
In accordance with
480 V at 60 Hz
IEC 60038:2009, Table 1
Nominal line-to-neutral U V r.m.s. line-to-neutral voltage at the 230 V at 50 Hz
1-L-N
voltage fundamental frequency F in case
1
of 3 AC+N system
Static voltage tolerance % U % Variations of the r.m.s. line-to-line + 10 % /- 10 %
L-L
at train line level or line-to-neutral voltage at any
See Figure 2
location of the train line limited at
% U 200 m
L-N
Static voltage tolerance % U % Variations of the r.m.s. line-to-line + 10 % / - 14 %
Load
at load terminals or line-to-neutral voltage at load
See Figure 2
terminals supplied by a
transformer
In accordance with
IEC 60038:2009, Table 1, and to
EN 50160:2007, 4.3
NOTE Values are given in steady state and normal conditions (no overload).
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+1+100%% +1+100%%
-5-5%% -10-10%%
AAuuxxiliailiarryy
coconvnveerrtteerr
+1+100%%
-1-144%%
LoadLoad
LoaLoaLoaddd
Figure 2 Static voltage tolerances along the train line
4.4 Voltage harmonics
The train line voltages are not pure sinusoidal waveforms, voltage harmonics due to the switching of
the auxiliary converters or non linear loads are present in the line. Table 3 gives the TDR (Total
Distortion Ratio) acceptable in steady state conditions without overload when sine filters are installed
at the auxiliary converter outputs.
Table 3 Voltage harmonics
Parameter Name Unit Description Value
TDR
Total Distortion Ratio % Total line-to-line or line-to-neutral ≤ 8 %
Lin
with linear loads (TDR) voltage harmonic components with
a linear load up to 100 % of the
rated apparent output power of the
auxiliary converter
TDR
Total Distortion Ratio % Total line-to-line or line-to-neutral ≤ 10 %
NLin
with non-linear loads voltage harmonic components with
a non-linear load up to 10 % of the
rated output apparent power of the
auxiliary converter in normal
conditions (no overload )
Non linear load is supposed here
to be a three-phase diode bridge
rectifier with a very large choke at
DC side which produces a quasi-
square waveform current in the
three-phase train line.
4.5 Voltage unbalance
Due to single phase loads connected to the train line and the inevitable impedance of the network, the
three-phase voltage amplitudes can be unbalanced. The consequence could be additional losses in
the three-phase asynchronous motors. Table 4 gives the current and voltage unbalance limits. The
train integrator shall try to balance the single phase load power between the three wires. Voltage
unbalance is generally calculated over a period of time in accordance with IEC and EN standards.
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Table 4 Current and voltage unbalances
Parameter Name Unit Description Value
Phase current (I -I )/I % Difference of any two-phase
≤ 10 %
1 2 N
unbalance currents divided by the rating
(I -I )/I
2 3 N
current (I ) of the auxiliary
N
converter
(I -I )/I
3 1 N
Voltage unbalance U /U % 10 min average of the ratio of the ≤ 2 %
2 1
(r.m.s.) r.m.s. values of the negative
phase sequence U over the
2
positive phase sequence U
1
In accordance with
EN 61000-2-2:2002, 4.6,
EN 50160:2007, 5.10,
EN 60034-26:2006, Clause 4, and
to EN 60146-2
Voltage unbalance U /U % Instantaneous ratio value of the
2 1 ≤ 5 %
(peak) r.m.s. values of the negative
phase sequence U over the
2
positive phase sequence U
1
NOTE Values are given in steady state and normal conditions (no overload).
4.6 Train line voltage amplitude and rate of rise
The semi-conductor switching of the auxiliary converters can entail fast variations on the train line
wires. The maximum voltage amplitude and rate of rise (dU/dt) on the different lines are given by
Table 5. Depending on the auxiliary system architecture and on the three-phase filter installed at the
outputs of the auxiliary converters, different values can be achieved: see Annex A.
The dU/dt is generally defined by the voltage variation (∆U) between 10 % and 90 % of the signal
during the rise (or fall) time. Figure 3 shows a typical voltage waveform (thin line) with high frequency
noise. To measure the proper dU/dt it is advised to slightly smooth the signal (bold line).
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Table 5 Train line voltage amplitude and rate of rise- dU/dt
Parameter Name Unit Description Value
Variation of line-to-line dU /dt V/µs Variations (rise time or fall time)
≤ 10 V/µs
L-L
voltage of the line-to-line voltages with
sine filter
dU /dt
Variation of line-to- V/µs Variations (rise time or fall time) ≤ 10 V/µs
L-N
neutral voltage of any line-to-neutral voltage with
sine filter
dU /dt
Variation of the line-to- V/µs Variations (rise time or fall time) ≤ 500 V/µs
L-E
earth voltage of any line-to-earth voltage when
See Figure 3
an auxiliary power converter
system architecture with only a
dU/dt filter is used
This dU/dt has to be taken in
consideration during the motor
design to avoid any Electrical
Discharge Machining (EDM)
phenomenon which could reduce
the bearing lifetime.
dU /dt
Variation of the star V/µs Variations (rise time or fall time) of ≤ 500 V/µs
O-E
point-to-earth voltage star point voltage or common
See
...
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