IEC TS 60349-3:2010

Electric traction - Rotating electrical machines for rail and road vehicles - Part 3: Determination of the total losses of converter-fed alternating current motors by summation of the component losses

IEC/TS 60349-3:2010 applies to machines complying with IEC 60349-2. The losses supplied at the fundamental frequency cannot be measured directly and so are derived from measurement of the fundamental frequency load current and the fundamental frequency no-load power input. The main technical changes with regard to the previous edition are corrections in some formulas in 3.2.1.2 and in Table A.2.

Traction électrique - Machines électriques tournantes des véhicules ferroviaires et routiers - Partie 3: Détermination des pertes totales des moteurs à courant alternatif alimentés par convertisseur par sommation des pertes élémentaires

La CEI/TS 60349-3:2010 s'applique aux machines satisfaisant à la CEI 60349-2. Les pertes fournies à la fréquence fondamentale ne peuvent pas être mesurées directement et par suite elles sont déduites des mesures du courant en charge et de la puissance d'entrée à vide à la fréquence fondamentale. Les principaux changements techniques par rapport à l'édition précédente sont des corrections dans certaines formules de 3.2.1.2 et dans le Tableau A.2.

General Information

• Status: Published
• Publication Date: 24-Mar-2010
• ICS: 45.060.01 - Railway rolling stock in general
• Technical Committee: TC 9 - Electrical equipment and systems for railways
• Drafting Committee: MT 30 - TC 9/MT 30
• Current Stage: PPUB - Publication issued
• Start Date: 25-Mar-2010
• Completion Date: 31-May-2010

Overview

IEC TS 60349-3:2010 is a technical specification developed by the International Electrotechnical Commission (IEC) that focuses on electric traction rotating electrical machines used in rail and road vehicles. Specifically, this part 3 of IEC 60349 addresses the determination of total losses in converter-fed alternating current (AC) motors by summing their component losses. It applies to machines compliant with IEC 60349-2 and provides measurement methodologies crucial for accurate loss assessment in traction motors powered through power electronic converters.

Converter-fed AC motors, typical in modern traction systems, present challenges in measuring losses due to harmonics and converter-induced frequencies. This specification offers a rigorous approach to estimate the total losses by combining no-load, load-dependent, and harmonic-related losses derived from specialized instrumentation and test methods.

Key Topics

• Scope
  Covers the loss determination techniques for converter-fed motors compliant with IEC 60349-2, emphasizing the summation of component losses rather than direct total power measurement.

• Loss Components

  • No-load losses at the fundamental frequency including iron and metal losses, friction, and windage.
  • Load-dependent losses such as I²R losses in stator and rotor (for asynchronous motors) and additional load-related losses like eddy currents induced by current-dependent flux pulsations.
  • Harmonic losses occurring at frequencies other than the fundamental frequency due to converter operation.
  • Brush contact and excitation circuit losses for synchronous motors.

• Instrumentation and Measurement
  Measurements require digital sampling instruments capable of simultaneous multi-phase voltage and current sampling. Total power is measured by voltage-current product over a period, while the fundamental power uses Fourier transforms. Accuracy with regard to phase shifts and harmonic distortion is critical. The specification outlines acceptable accuracy levels for wattmeters, attenuators, and current sensors.

• Summation Methodology
  Total losses are determined by summing the component losses, calculated or measured separately, including those arising at fundamental and harmonic frequencies. Formula corrections and annexes provide guidance on equivalent circuits and graphical methods for loss estimation.

• Technical Corrections
  This 2010 edition introduces corrections to formulas and parameter tables compared to the original 1995 publication, enhancing the precision of loss determination.

Applications

IEC TS 60349-3:2010 is highly valuable in:

• Rail and Road Vehicle Traction Systems
  Ensuring optimal performance and efficiency of AC traction motors by accurately quantifying all sources of power loss.

• Motor Design and Testing
  Offering manufacturers and testing laboratories clear guidelines to conduct loss measurement tests for converter-fed traction motors, facilitating conformity with IEC 60349-2.

• Maintenance and Condition Monitoring
  Supporting diagnostic procedures by establishing baseline loss components and identifying abnormal increases related to mechanical wear or electrical faults.

• Energy Efficiency Improvements
  Helping engineers and system designers quantify losses due to harmonics and load conditions to optimize converter settings and motor designs for reduced energy consumption.

• Standardization Compliance
  Enabling manufacturers and operators worldwide to adopt a harmonized method for loss determination, promoting interoperability and comparability.

Related Standards

• IEC 60349-2
  Defines the general requirements and testing methods for rotating electrical machines for rail and road vehicles, serving as the foundational standard for motor compliance referenced in IEC TS 60349-3.

• IEC 60034 Series
  Covers rotating electrical machines broadly, including testing and performance criteria relevant to traction motors.

• ISO/IEC Directives Part 2
  Governs the preparation and drafting of IEC publications, including technical specifications like IEC TS 60349-3.

• IEC 61800 Series
  Pertains to adjustable speed electrical power drive systems and may interface with converter-fed motor standards concerning harmonics and losses.

Summary

IEC TS 60349-3:2010 delivers essential guidelines and technical methodologies for accurately determining total losses in converter-fed AC motors used in rail and road traction applications. By breaking down losses into measurable components and addressing challenges related to harmonics and converter supply, it provides a practical and reliable approach to loss calculation. This enhances motor efficiency analysis, supports maintenance planning, and contributes to the global harmonization of testing and evaluation procedures in traction motor technology.

For engineers, manufacturers, and operators engaged with electric traction systems, IEC TS 60349-3 is a foundational technical specification that ensures precise measurement and understanding of motor losses, driving improved performance and energy savings.

Standards Content (Sample)

IEC/TS 60349-3 ®
Edition 2.0 2010-03
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Electric traction – Rotating electrical machines for rail and road vehicles –
Part 3: Determination of the total losses of converter-fed alternating current
motors by summation of the component losses

Traction électrique – Machines électriques tournantes des véhicules ferroviaires
et routiers –
Partie 3: Détermination des pertes totales des moteurs à courant alternatif
alimentés par convertisseur par sommation des pertes élémentaires

IEC/TS 60349-3:2010
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IEC/TS 60349-3 ®
Edition 2.0 2010-03
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Electric traction – Rotating electrical machines for rail and road vehicles –
Part 3: Determination of the total losses of converter-fed alternating current
motors by summation of the component losses

Traction électrique – Machines électriques tournantes des véhicules ferroviaires
et routiers –
Partie 3: Détermination des pertes totales des moteurs à courant alternatif
alimentés par convertisseur par sommation des pertes élémentaires

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
Q
CODE PRIX
ICS 45.060 ISBN 978-2-88910-173-3
– 2 – TS 60349-3 © IEC:2010
CONTENTS
FOREWORD.3
1 Scope and object.5
2 Instrumentation .5
3 Summation of losses .6
3.1 The total losses are the sum of the following component losses. .6
3.2 Determination of the component losses .7
3.2.1 Asynchronous motors .7
3.2.2 Synchronous motors.8
Annex A (informative) The equivalent circuit of an asynchronous motor .10
Annex B (informative) Stray load loss .16

Figure 1 − Derivation of equivalent 50 Hz rated power input.8
Figure A.1 − Equivalent circuit of an asynchronous motor on no-load.10
Figure A.2 − Equivalent circuit of an asynchronous motor on load.13
Figure A.3 − Graphical method for determining friction and windage loss.15

Table 1 − Accuracy of external attenuators .6
Table 2 − Overall accuracy of power measurement .6
Table A.1 − Determination of parameters of the equivalent circuit .11
Table A.2 – Definition of parameters .14

TS 60349-3 © IEC:2010 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRIC TRACTION –
ROTATING ELECTRICAL MACHINES
FOR RAIL AND ROAD VEHICLES –
Part 3: Determination of the total losses
of converter-fed alternating current motors
by summation of the component losses

FOREWORD
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all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
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The main task of IEC technical committees is to prepare International Standards. In
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• the required support cannot be obtained for the publication of an International Standard,
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Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.

– 4 – TS 60349-3 © IEC:2010
IEC 60349-3, which is a technical specification, has been prepared by IEC technical
committee 9: Electrical equipment and systems for railways.
This second edition cancels and replaces the first edition, issued in 1995, and constitutes a
technical revision.
The main technical changes with regard to the previous edition are as follows:
– Omissions in some formulas in 3.2.1.2 and Table A.2 were fixed.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
9/1267/DTS 9/1342/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.
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 be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
TS 60349-3 © IEC:2010 – 5 –
ELECTRIC TRACTION –
ROTATING ELECTRICAL MACHINES
FOR RAIL AND ROAD VEHICLES –
Part 3: Determination of the total losses
of converter-fed alternating current motors
by summation of the component losses

1 Scope and object
This technical specification applies to machines complying with IEC 60349-2.
The total losses of a converter-fed motor may be determined by summation of the component
losses derived from no-load and load tests. The total input power is the sum of the power at
the fundamental frequency and at all other frequencies. In all practical cases the latter input
includes the losses resulting from the voltage and current harmonics in the converter supply
by using suitable instrumentation it can be derived from measurement of the total and
fundamental frequency power inputs when the machine is on load.
The losses supplied at the fundamental frequency cannot be measured directly and so are
derived from measurement of the fundamental frequency load current and the fundamental
frequency no-load power input.
2 Instrumentation
The extra loss due to operation on a converter supply is obtained from the difference of the
total and fundamental frequency power input on load.
The power inputs shall be measured simultaneously on each phase by a digital sampling
instrument. Measurement on all three phases is preferred but the two wattmeter method is
permissible as an alternative.
The total power is obtained from the product of voltage and current over a period of time and
the fundamental power from a Fourier transform using the same sampling.
It is necessary to consider the accuracy of the whole instrument chain taking into account
both amplification and phase shift errors over the desired frequency range. As the power
factor of the harmonics is generally very low (less than 0,1 for voltage imposed asynchronous
systems) particular attention is drawn to the need for minimum phase angle errors.
At the time of publication of this technical specification, wattmeters accurate within the
following limits, at 0,08 power factor, were available:
below 2 kHz  ±0,5 %;
between 2 kHz and 20 kHz  ±1,0 %;
between 20 kHz and 50 kHz ±2,0 %.
Instruments often contain attenuators compensated and adapted to them, but if an external
attenuator is used, it is desirable that it be accurate within the following limits given in
Table 1.
– 6 – TS 60349-3 © IEC:2010
Table 1 − Accuracy of external attenuators
Frequency Ratio error Phase shift error
kHz % degrees
< 2 ±0,5 ±0,1
2 to 20 ±1,0 ±0,2
20 to 50
±2,0 ±0,5
Taking all factors into account, Table 2 lists the highest overall accuracy of power
measurement which it is considered could be achieved at the time of publication of this
specification.
Table 2 − Overall accuracy of power measurement
Frequency Power factor 0,4
Power factor >0,8 Power factor <0,1
kHz % % %
< 2 ±1 ±2 ±10
2 to 20
±2 ±5 ±14
20 to 50 ±4 ±8 ±20
NOTE The frequency range over which measurements are necessary depends on the harmonic content of the
output from the particular converter used and should therefore be decided for each individual case. With the
instrumentation presently available, the overall accuracy of the total harmonic loss measurement is likely to be of
the order of ±10 %, but as the loss is unlikely to exceed 3 % of the total power input, this will result in only 0,3 %
error in the calculated torque, which is well within the permitted tolerance of −5 % specified in IEC 60349-2.
At the time of publication of this technical specification, current transformers are significantly less accurate at the
low power factors and high harmonic frequencies involved than non-inductive shunts, which can have a ratio
accuracy within ±1 % and a phase shift within ±0,2°.
3 Summation of losses
3.1 The total losses are the sum of the following component losses.
3.1.1 Losses supplied at the fundamental frequency on no-load (no-load losses):
− losses in the active iron and other metal parts;
− losses due to friction and windage including the power absorbed by integral fans.
3.1.2 Losses which occur when the motor is supplied at the fundamental frequency and
which vary with load (load dependent losses):
− I R losses in the stator windings;
− I R losses in the rotor winding of asynchronous motors;
− additional load losses (load loss) consisting of:
• losses in the active iron and metal parts other than the conductors;
• eddy current losses in the stator and rotor windings arising from current dependent flux
pulsation.
3.1.3 Losses supplied at other than the fundamental frequency.
3.1.4 I R and brush contact losses in the excitation circuit of synchronous motors.

TS 60349-3 © IEC:2010 – 7 –
3.2 Determination of the component losses
3.2.1 Asynchronous motors
3.2.1.1 No-load losses supplied at the fundamental frequency
The losses shall be determined by running the motor on no-load at the voltage and
fundamental frequency of the point on the specified characteristic for which they are being
determined. The losses shall be taken as the fundamental frequency power input minus the
2 2
I R loss in the stator. The no-load I R loss in the rotor shall be neglected.
3.2.1.2 Load dependent losses supplied at the fundamental frequency
The fundamental frequency I R losses in the stator shall be calculated from the fundamental
frequency current in each winding at the point for which the losses are being determined and
from the measured resistance of the winding corrected to the temperature of reference.
The I R loss in the rotor winding shall be taken as:
s × [ P – (l R + P − P ) ]
f pf of fw
where
s is the slip;
P is the fundamental frequency input power;
f
2 2
I R is the stator fundamental frequency I R loss;
pf
P are the fundamental frequency no-load losses;
of
P is the friction and windage loss.
fw
NOTE 1 The friction and windage loss should be determined either by driving the motor on open circuit by a
calibrated machine or by the graphical method described in Annex A. The drive may be through a transmission
system of known efficiency.
Unless otherwise specified, the additional load losses at current I and fundamental frequency
f (in Hz) shall be taken as:
2 1,5
P = P × (I / I ) × (f / 50) × 0,01
s 50 r
where
P is the additional load losses;
s
P is the equivalent 50 Hz rated input power;
I  is the total current at the guaranteed rating.
r
The equivalent 50 Hz rated input power is based on the assumption that the rated current is
independent of frequency and that the motor voltage and input power are both proportional to
frequency over the range of operation with full flux (see Figure 1), that is:
P = P × 50 / f
50 m m
where
P is the assumed input power at maximum voltage, rated current and full flux;
m
is the fundamental frequency (in Hz) at input power P .
f
m m
NOTE 2 At the time of publication of this specification, the validity of the formula in all cases had not been fully
established by experience. Additional information may be obtained by carrying out a low power test described in
Annex B.
NOTE 3 This calculation may be applied not only at 50 Hz but also similarly at 60 Hz.

– 8 – TS 60349-3 © IEC:2010
Power
Power
P
m
Voltage
Current
Voltage
Current I
V
r
max.
P
f
m
Frequency  (Hz)
50 100
IEC  536/10
Figure 1 − Derivation of equivalent 50 Hz rated power input
3.2.1.3 Losses supplied at other than the fundamental frequency
The losses arising from the supply harmonics are the difference between the total and
fundamental frequency power inputs to the motor when on load with the stator windings at
approximately the temperature of reference.
NOTE If the converter is a voltage source type and its modulation pattern is independent of load, the difference
may be measured on no-load.
3.2.2 Synchronous motors
3.2.2.1 No-load losses supplied at the fundamental frequency
The motor shall be driven on open circuit by a calibrated machine at the speed for which the
losses are being determined and shall be excited by an independent source to generate the
voltage shown on the specified characteristic at the same speed. The losses are equal to the
mechanical power input to the motor shaft.
3.2.2.2 Load dependent losses supplied at the fundamental frequency
The fundamental frequency I R losses in the stator shall be calculated from the fundamental
frequency current in each winding at the point for which the losses are being determined and
from the measured resistance of the winding corrected to the temperature of reference.
Unless otherwise specified, the additional load losses shall be determined by driving the
machine with the stator windings short-circuited at the speed of the point on the specified
characteristic for which the losses are being determined. The excitation shall be adjusted to
give the fundamental frequency stator winding currents for the same point. The losses shall
be taken as the power supplied to the machine shaft minus the sum of the total stator I R
losses and the power supplied when the machine is driven unexcited at the same speed.
3.2.2.3 Losses supplied at other than the fundamental frequency
The losses arising from the supply harmonics are the difference between the total and funda-
mental frequency power inputs to the motor when on load with the windings at approximately
the temperature of reference.
TS 60349-3 © IEC:2010 – 9 –
3.2.2.4 Loss in the excitation circuit
The loss in the excitation circuit shall be the product of the current in the winding and the total
excitation voltage at the point for which the losses are being determined. The voltage shall be
the value required to supply the excitation current with the winding at the temperature of
reference. Account shall be taken of any ripple in the excitation current.
NOTE The specified characteristic may state that the excitation power is not included in the calculated motor
losses as it is accounted for elsewhere, for example as part of the vehicle auxiliary load.

– 10 – TS 60349-3 © IEC:2010
Annex A
(informative)
The equivalent circuit of an asynchronous motor

A.1 Circuit description
An asynchronous motor on no-load can be represented by the equivalent circuit illustrated in
Figure A.1. The circuit parameters are obtained from no-load and impedance (locked rotor)
tests on a sinusoidal supply voltage, the quantities measured being voltage, current and
power.
If the circuit parameters and no-load losses are determined for a number of voltages and
frequencies covering the range of operation of the motor, curves can be plotted which enable
the motor torque and input current to be calculated for chosen values of voltage, frequency
and slip.
I I
1 R X 21 X
1 1 21
+
R
U 21
X E R
M M
s
IEC  537/10
Key
f frequency (Hz);
U phase voltage (V);
I stator current (A);
I rotor current transformed to the stator side (A);
X stator reactance (Ω);
X rotor reactance transformed to the stator side (Ω);
R stator resistance (Ω);
R rotor resistance transformed to the stator side (Ω);
X magnetizing reactance (Ω);
M
R magnetizing resistance (Ω);
M
E induced electromotive force (e.m.f.) (V);
s slip (-);
P input power on no-load (W);
P stator resistance losses (W);
Cu1
P core loss (W);
Fe
P friction and windage loss (W);
fw
Q total reactive power on no-load (VAr);
Q total reactive power with locked rotor ( VAr ).
1L
Figure A.1 − Equivalent circuit of an asynchronous motor on no-load

TS 60349-3 © IEC:2010 – 11 –
A.2 Determination of the parameters of the equivalent circuit of a three-phase
motor
The parameters of the equivalent circuit are derived from the equations given in Table A.1.
The definition of the parameters is given in Table A.2.
An additional suffix "0" denotes measurements on no-load.
An addition suffix "L" denotes measurements with a locked rotor.
Table A.1 − Determination of parameters of the equivalent circuit
Parameter Description Equation
X U , I , P are measured on no-load.
U 1
M 10 10 10
X = 3 × (1)
M 2 2
QI− 3X (1+X /X )
The values of X and X at the first iteration are
10 1011M
1 M
the theoretical calculated ones.
2 2
QU=×(3 ×I )−P
]
10 [ 10 10 10
X X is the stator reactance at the frequency f
1L 1L L
used for the impedance test. The values of X
Q X//X + X X
1L 121 1 M
and X at the first iteration are the theoretically
X=× (2)
1L
1/++XX XX/
calculated ones. 3 I
121 1 M
1L
X is obtained from equation (1)
m
2 2
QU=×(3 ×I )−P
[ ]
1L 1L 1L 1L
X X is the stator reactance at frequency f. f
1 1
X=× X (3)
1 1L
f
L
X is obtained from equation (2).
1L
b b is the magnetic susceptance. 1
M M
b = (4)
M
X
M
is obtained from equation (1).
X
M
X X is the rotor reactance transformed to the X
21 21
X = (5)
stator side.
(/XX )
X is obtained from equation (3).
P P is the core loss.
Fe Fe
P and I are measured values of the no-load
10 10
active power and current.
P is the friction and windage loss which is
fw
PP=−P− 3IR (6)
determined graphically or measured by driving
Fe 10 fw 10 1
the motor disconnected from the supply.
R is the stator resistance at the temperature of
the winding during the no-load test.
G G is the magnetizing conductance.
M M
P is obtained from equation (6).
Fe ⎛ ⎞
P X
Fe 1
G=+1 (7)
⎜ ⎟
M
U is the measured no-load voltage. 3 X
U ⎝ ⎠
M
10 10
X is obtained from equation (3) and X from
1 M
equation (1).
R R is the magnetizing resistance. 1
M M
R = (8)
M
G
M
G is obtained from equation (7).
M
R R is the rotor resistance, at a specified (see note 4)
21 21
temperature, transformed to the stator side.
NOTE 1 Equations (1), (2) and (3) should be calculated in ascending order, i.e (1), (2), (3); (1), (2), (3); (1),
(2), (3) and so on. The calculations should be iterated until the errors for X and X are less than 0,1 %, i.e the
1 M
difference between the values of two successive iterations should be less than 0,1%. After the iteration of
equations (1), (2) and (3), all subsequent equations should be calculated in ascending order.

– 12 – TS 60349-3 © IEC:2010
Parameter Description Equation
The calculation gives correct values of the parameters if a sufficient number of iterations is carried out. Its
accuracy is dependent only on the accuracy of the results of no load and impedance tests.
The calculation gives a correct value of X + X with a fixed ratio of X /X equal to the theoretical value of the
1 21 1 21
ratio.
NOTE 2 On no-load the rotor and friction and windage losses are negligible compared with the stator losses
which enables the magnetizing reactance to be calculated by equation (1) based on the results of a no-load test
applied to a simplified circuit.
NOTE 3 The stator reactance X and the rotor reactance X are calculated from the results of a locked rotor
1 21
test at a frequency as close as practicable to the actual rotor frequency. (In practice, the test frequency is
normally above the actual frequency, 15 Hz being a suitable value.)
Current, voltage and power factor are measured. The magnetizing resistance R is much higher than the
M
transformed rotor resistance to the stator side R and therefore a simplified circuit is used.
NOTE 4 The rotor resistance R can either be derived from the impedance test results or from measurements
made on a load test. The latter is preferred because:
a) thermal steady state conditions can be achieved;
b) the rotor frequency is the actual value, which is not generally the case during an impedance locked
rotor) test.
Determination from an impedance test
2 2
⎛ ⎞ ⎛ ⎞ ⎛ ⎞ 2
P X X X
1L 21 21 1L
⎜ ⎟ ⎜ ⎟ ⎜ ⎟
R=− R 1+ −
21 1
⎜ 2 ⎟ ⎜ ⎟ ⎜ ⎟
3 I X X R
⎝ ⎠ ⎝ ⎠ ⎝ ⎠
1L M 1 M
P and I are the active power and stator current with a locked rotor.
1L 1L
Note that this equation is only valid if R is determined from an impedance test.
Determination from a load test
The parameters at the test point are calculated by the equivalent circuit method using chosen values of R until
the calculated input current equals the test value. The final value of R is then used for all subsequent
calculations.
A.3 Calculation of the characteristic of a three-phase motor
When curves of the equivalent circuit parameters and the no-load losses have been plotted
they can be used to calculate points on the motor characteristic for chosen values of voltage,
frequency and slip.
Figure A.2 is the equivalent circuit of an asynchronous motor on load. Note that the circuit
parameters do not take into account friction, windage, stray and converter supply harmonic
losses which are therefore allowed for separately.

TS 60349-3 © IEC:2010 – 13 –
I I
1 21
R X X R
1 1 21 21
a
+
P Z
in
R (1–s)
U
X E R
M M
s
b
IEC  538/10
NOTE Input data
Phase voltage
Fundamental supply frequency
Slip
Friction and windage losses
Stray losses
Harmonic losses arising from the converter supply
Equivalent circuit parameters at the fundamental frequency:
X , X , X , R , R , R
1 21 M 1 M 21
Output data
Stator current
Input power
Output power
Efficiency
Power factor
Shaft torque
Figure A.2 − Equivalent circuit of an asynchronous motor on load

– 14 – TS 60349-3 © IEC:2010
Table A.2 – Definition of parameters
Item Parameter Equation*
1 s is the slip [ p.u ] input data
2 X is the stator reactance [Ω] input data
3 X is the rotor reactance transformed to the stator side [ Ω ] input data
4 X is the magnetizing reactance [ Ω ] input data
M
5 R is the stator resistance [ Ω ] input data
6 R is the rotor resistance transformed to the stator side [ Ω ] input data
7 R is the magnetizing resistance [ Ω ] input data
M
8 U is the phase voltage [ V ] input data
9 f is the fundamental supply frequency [ Hz ] input data
10 m is the number of phases (m=3) input data
11 P is the harmonic loss caused by the converter [W ] input data
h
supply  (see note 1)
12 R /s is a resistance in the equivalent circuit [ Ω ] (6)/(1)
2 2 2
13 Z is an auxiliary variable (3) + (12)
14 G is an auxiliary variable (12)/(13)
–1
15 G is the core conductance [ Ω ] (1)/(7)
Fe
16 G is an auxiliary variable (14) + (15)
17 B is an auxiliary variable (3)/(13)
–1
18 b is the magnetizing susceptance [ Ω ] 1/(4)
M
19 B is an auxiliary variable (17) + (18)
20 Y is an auxiliary variable (16) + (19)
21 R is an auxiliary variable (16)/(20)
G
22 R is the auxiliary variable (5) + (21)
23 X is an auxiliary variable (19)/(20)
G
24 X is an auxiliary variable (23)+(2)
25 Z is the total impedance of the equivalent circuit [ Ω ] (21) + (23)
[]
26 I is the stator current [ A ] U /(25)
27 P is the input power excluding item (11) [ W ] (10) × (26) × (22)
in
2 2
28 P is the I R loss in the stator (10) × (26) × (5)
cu1
29 P is the core loss [ W ] (10) × (26) × (15)/(20)
Fe
30 P is the rotor input [ W ] (27) – (28) – (29)
in2
31 P is te I R loss in the rotor [ W ] (1) × (30)
cu2
32 n is the motor speed [ tr/min ] ns x [ 1 – (1) ]
ns is the synchronous speed
33 P is the friction and windage loss [ W ] (see note 2)
fw
34 P is the stray loss [ W ] (see note 3)
s
35 ΣP is the total power loss excluding item (11) [ W ] (28) + (29) + (31) + (33) + (34)
36 P is the output power (27) – (35)
ou
37 η is the efficiency excluding item (11) [ p.u ] 1 – (35)/(27)
38 η is the efficiency including item (11) [ p.u ] 1 – [(11) + (35)]/[(27) + (11)]
39 PF is the power factor excluding item (11) [ p.u ] (22)/(25)
40 T is the output torque [ Nm ]   (60 / 2π) × [(36)/(32)]
* In the equations, numbers in parentheses, e.g. (21), are item numbers.
NOTE 1 The harmonic losses arising from the converter supply are measured on load as specified in 3.2.1.3.
NOTE 2 Determination of the friction and windage loss from no-load tests.
The graph of the total no-load loss as a function of the square of the terminal voltage at constant frequency is a
straight line. Extrapolating the graphs to zero voltage for a number of frequencies and voltages, Figure A.3 allows
a curve of the friction and windage loss against speed to be plotted. Alternatively, the loss can be measured by
driving the motor disconnected from the supply.
NOTE 3 The stray losses are allowed for by the formula specified in 3.2.1.2.

TS 60349-3 © IEC:2010 – 15 –
P + P
fw Fe
f
f
f
P
fw3
P
fw2
P
fw1
U
IEC  539/10
Figure A.3 − Graphical method for determining friction and windage loss

– 16 – TS 60349-3 © IEC:2010
Annex B
(informative)
Stray load loss
B.1 Determination of the stray load losses in asynchronous cage type motors
by low power testing
A value for the stray load losses of a cage type motor can be obtained by a two-part low
power test. The losses are not measured directly. Investigation tests as defined in 5.1.4 of
IEC 60349-2 should be carried out to provide data for further consideration.
The losses at the fundamental and higher frequencies are determined by two separate tests,
the total stray loss P being the sum of the two.
s
B.2 Fundamental frequency loss (test with the rotor removed)
The fundamental frequency loss P is determined by passing a balanced polyphase current
ff
through the stator with the rotor removed but with all stator parts in which current might be
induced in place. The test current corresponding to a motor input current I shall be I :
t
II=−( I )
t 0
where I is the motor no-load current at the same voltage and frequency.
The fundamental frequency loss P at line current I is
ff
P − I R
sr t f
where
P is the total power input to the stator at line current I ;
sr t
2 2
I R is the total I R loss in the stator at line current I and winding temperature t .
t f t f
B.3 Loss at higher frequencies (reverse rotation test)
The loss at higher frequencies P is determined by driving the motor at synchronous speed in
hf
the opposite direction to the stator field rotation with and without a voltage applied which
produces the same stator current I as for the test with the rotor removed.
t
The total loss at higher frequencies, P is
hf
(P − P ) − (P − P − I R )
mr fw rr ff t h
where
P is the mechanical power input with voltage applied;
mr
P is the mechanical power input without voltage applied;
fw
P is the electrical power input to the stator during reverse rotation;
rr
2 2
I R is the total I R loss in the stator at line current I and winding temperature t .
t h t h
The total stray loss P is P + P .
s ff hf
TS 60349-3 © IEC:2010 – 17 –
NOTE 1 If the error arising from the winding temperature difference during the two tests is neglected, P can be
hf
taken as equal to (P – P ) – (P – P ).
mr fw rr sr
NOTE 2 It is recommended that curves of P and P be plotted against stator current for a number of fre-
ff hf
quencies to enable the total stray loss to be determined for any point within the working range of the motor.
NOTE 3 The instrumentation should be suitable for measuring the low power factor electrical input.

_____________
– 18 – TS 60349-3 © CEI:2010
SOMMAIRE
AVANT-PROPOS.19
1 Domaine d'application et objet.21
2 Instrumentation de mesure .21
3 Sommation des pertes.22
3.1 Les pertes totales sont la somme des pertes élémentaires suivantes. .22
3.2 Détermination des pertes élémentaires.23
3.2.1 Moteurs asynchrones .23
3.2.2 Moteurs synchrones .24
Annexe A (informative) Circuit équivalent d'un moteur asynchrone .26
Annexe B (informative) Pertes supplémentaires en charge .32

Figure 1 − Obtention de la puissance d'entrée assignée équivalente à 50 Hz.24
Figure A.1 − Circuit équivalent d'un moteur asynchrone à vide .26
Figure A.2 − Circuit équivalent d'un moteur asynchrone en charge .29
Figure A.3 − Méthode graphique de détermination des pertes par frottement et
ventilation .31

Tableau 1 − Précision d’un atténuateur externe .22
Tableau 2 − Précision globale de mesure de puissance .22
Tableau A.1 − Détermination des paramètres du circuit équivalent .27
Tableau A.2 – Définition des paramètres .30

TS 60349-3 © CEI:2010 – 19 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
TRACTION ÉLECTRIQUE –
MACHINES ÉLECTRIQUES TOURNANTES
DES VÉHICULES FERROVIAIRES ET ROUTIERS –

Partie 3: Détermination des pertes totales des moteurs
à courant alternatif alimentés par convertisseur
par sommation des pertes élémentaires

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (CEI) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a
pour objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les
domaines de l'électricité et de l'électronique. A cet effet, la CEI – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
public (PAS) et des Guides (ci-après dénommés "Publication(s) de la CEI"). Leur élaboration est confiée à des
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également aux travaux. La CEI collabore étroitement avec l'Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de la CEI concernant les questions techniques représentent, dans la mesure
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8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L’attention est attirée sur le fait que certains des éléments de la présente Publication de la CEI peuvent faire
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La tâche principale des comités d’études de la CEI est l’élaboration des Normes
internationales. Exceptionnellement, un comité d’études peut proposer la publication d’une
spécification technique
• lorsqu’en dépit de maints efforts, l’accord requis ne peut être réalisé en faveur de la
publication d’une Norme internationale, ou
• lorsque le sujet en question est encore en cours de développement technique ou quand,
pour une raison quelconque, la possibilité d’un accord pour la publication d’une Norme
internationale peut être envisagée pour l’avenir mais pas dans l’immédiat.

– 20 – TS 60349-3 © CEI:2010
Les spécifications techniques font l’objet d’un nouvel examen trois ans au plus tard après leur
publication afin de décider éve
...