IEC TS 60034-31:2010

IEC/TS 60034-31 ®
Edition 1.0 2010-04
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
colour
inside
Rotating electrical machines –
Part 31: Selection of energy-efficient motors including variable speed
applications – Application guide

Machines électriques tournantes –
Partie 31: Choix des moteurs éconergétiques incluant les applications à vitesse
variable – Guide d’application

IEC/TS 60034-31:2010
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IEC/TS 60034-31 ®
Edition 1.0 2010-04
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
colour
inside
Rotating electrical machines –
Part 31: Selection of energy-efficient motors including variable speed
applications – Application guide

Machines électriques tournantes –
Partie 31: Choix des moteurs éconergétiques incluant les applications à vitesse
variable – Guide d’application

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
X
CODE PRIX
ICS 29.160 ISBN 978-2-88910-023-1
– 2 – TS 60034-31 © IEC:2010
CONTENTS
FOREWORD.5
INTRODUCTION.7
1 Scope.8
2 Normative references .8
3 Terms, definitions and symbols .8
3.1 Terms and definitions .8
3.2 Symbols .8
4 General .9
5 Efficiency .10
5.1 General .10
5.2 Motor losses.11
5.3 Additional motor-losses when operated on a frequency converter.12
5.4 Motors for higher efficiency classes.12
5.5 Variations in motor losses .13
5.6 Part load efficiency.14
5.7 Efficiency testing methods.15
5.8 Power factor (see Figure 4) .16
5.9 Matching motors and variable frequency converters .17
5.10 Motors rated for 50 Hz and 60 Hz.18
5.11 Motors rated for different voltages or a voltage range.20
5.12 Motors rated for operation at frequencies other than 50/60 Hz.20
5.13 Variable frequency converter efficiency .20
5.14 Frequency converter power factor .22
6 Environment .22
6.1 Starting performance.22
6.2 Operating speed and slip.23
6.3 Effects of power quality and variation in voltage and frequency .23
6.4 Effects of voltage unbalance .23
6.5 Effects of ambient temperature.24
7 Applications.24
7.1 General .24
7.2 Energy savings by speed control (variable speed drives, VSD).24
7.3 Correct sizing of the motor .24
7.4 Continuous duty application .25
7.5 Applications involving extended periods of light load operations.25
7.6 Applications involving overhauling loads.26
7.7 Applications where load-torque is increasing with speed (pumps, fans,
compressors, etc.).26
7.8 Applications involving frequent starts and stops and/or mechanical braking.27
7.9 Applications involving explosive gas or dust atmospheres .27
8 Economy .28
8.1 Relevance to users.28
8.2 Initial purchase cost .28
8.3 Operating cost.29
8.4 Rewinding cost.30
8.5 Payback time.31

TS 60034-31 © IEC:2010 – 3 –
8.6 Life cycle cost .31
9 Maintenance.32
Annex A (informative) Super-premium efficiency (IE4) .34
Bibliography.40

Figure 1 – Overview of different areas for savings of electrical energy with drive
systems .9
Figure 2 – Typical losses of energy-efficient motors, converters and electro-
mechanical brakes.10
Figure 3 – Typical efficiency versus load curve bands for three-phase, cage-induction
motors of different output power ranges (approximately 1,1 kW, 15 kW and 150 kW).14
Figure 4 – Typical power factor versus load curve bands for three-phase, cage-
induction motors of different output power ranges (approximately 1,1 kW, 15 kW and
150 kW) .16
Figure 5 – Typical reduction of energy efficiency in %-points for 4-pole, low-voltage
motors between 50 Hz and 60 Hz when compared at the same torque (60 Hz power 20
% increased).19
Figure 6 – Typical reduction of energy efficiency in %-points for 4-pole, low-voltage
motors between 50 Hz and 60 Hz when compared at the same output power (60 Hz
torque 20 % reduced) .19
Figure 7 – Typical efficiency of indirect three-phase voltage source type converters
with a passive front-end for typical load points of pumps, fans and compressors .20
Figure 8 – Typical efficiency of indirect three-phase voltage source type converters
with a passive front-end for typical load points of constant torque.21
Figure 9 – Typical variations of current, speed, power factor and efficiency with
voltage for constant output power .23
Figure 10 – Potential energy savings by improvement of efficiency classes for motors
running at rated load.25
Figure 11 – Typical torque versus speed curves for 11 kW, 4-pole, three-phase, cage-
induction motors and load versus speed curves for speed-square-loads .26
Figure 12 – 11 kW IE3 motor operated at full load, 4 000 operating hours per year, 15
years life cycle.28
Figure 13 – Example of a load factor graph: fraction of annual operating hours .29
Figure 14 – Life cycle cost analysis of an 11 kW motor operating at full load .32
Figure A.1 – IE4 efficiency limits.39

Table 1 – Loss distribution in three-phase, 4-pole, cage-induction electric motor
...