Rotating electrical machines - Part 31: Selection of energy-efficient motors including variable speed applications - Application guide

IEC/TS 60034-31:2010 provides a guideline of technical aspects for the application of energy-efficient, three-phase, electric motors. It not only applies to motor manufacturers, original equipment manufacturers, end users, regulators and legislators but to all other interested parties. Is applicable to all electrical machines covered by IEC 60034-30.

Drehende elektrische Maschinen - Teil 31: Auswahl von Energiesparmotoren einschließlich Drehzahlstellantrieben - Anwendungsleitfaden

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

La CEI/TS 60034-31:2010 donne une ligne directrice concernant les aspects techniques relatifs à l'application des moteurs électriques éconergétiques triphasés. Elle s'applique non seulement aux fabricants de moteurs, aux fabricants originaux d'équipement, aux utilisateurs finaux, aux autorités de réglementation et aux législateurs, mais également à toutes les autres parties intéressées. Est applicable à toutes les machines électriques couvertes par la CEI 60034-30.

Električni rotacijski stroji - 31. del: Izbiranje energijsko učinkovitih motorjev vključno z motorji s spremenljivo hitrostjo - Navodilo za uporabo (IEC/TS 60034-31:2010)

Ta del IEC 60034 zagotavlja smernico za tehnične vidike uporabe energijsko učinkovitih trofaznih elektromotorjev. Ne velja le za proizvajalce motorjev, prvotne proizvajalce opreme, končne uporabnike, regulatorne organe, zakonodajalce, pač pa tudi za vse druge zainteresirane strani.
Ta tehnična specifikacija velja za vse električne stroje, ki jih zajema IEC 60034-30. Večina informacij pa velja tudi za asinhronske stroje z izhodno močjo 375 kW.

General Information

Status
Published
Publication Date
24-Feb-2011
Technical Committee
Drafting Committee
Current Stage
6060 - Document made available
Completion Date
25-Feb-2011

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SLOVENSKI STANDARD
SIST-TS CLC/TS 60034-31:2011
01-maj-2011

(OHNWULþQLURWDFLMVNLVWURMLGHO,]ELUDQMHHQHUJLMVNRXþLQNRYLWLKPRWRUMHY

YNOMXþQR]PRWRUMLVVSUHPHQOMLYRKLWURVWMR1DYRGLOR]DXSRUDER ,(&76


Rotating electrical machines - Part 31: Selection of energy-efficient motors including

variable speed applications - Application guide (IEC/TS 60034-31:2010)
Drehende elektrische Maschinen - Teil 31: Auswahl von Energiesparmotoren

einschließlich Drehzahlstellantrieben - Anwendungsleitfaden (IEC/TS 60034-31:2010)

Machines électriques tournantes - Partie 31: Choix des moteurs éconergétiques incluant

les applications à vitesse variable - Guide d’application (CEI/TS 60034-31:2010)
Ta slovenski standard je istoveten z: CLC/TS 60034-31:2011
ICS:
29.160.30 Motorji Motors
SIST-TS CLC/TS 60034-31:2011 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS CLC/TS 60034-31:2011
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SIST-TS CLC/TS 60034-31:2011
TECHNICAL SPECIFICATION
CLC/TS 60034-31
SPÉCIFICATION TECHNIQUE
February 2011
TECHNISCHE SPEZIFIKATION
ICS 29.160
English version
Rotating electrical machines -
Part 31: Selection of energy-efficient motors including variable speed
applications -
Application guide
(IEC/TS 60034-31:2010)
Machines électriques tournantes - Drehende elektrische Maschinen -
Partie 31: Choix des moteurs Teil 31: Auswahl von Energiesparmotoren

éconergétiques incluant les applications à einschließlich Drehzahlstellantrieben -

vitesse variable - Anwendungsleitfaden
Guide d’application (IEC/TS 60034-31:2010)
(CEI/TS 60034-31:2010)
This Technical Specification was approved by CENELEC on 2011-02-21.

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 60034-31:2011 E
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SIST-TS CLC/TS 60034-31:2011
CLC/TS 60034-31:2011 - 2 -
Foreword

The text of the Technical Specification IEC/TS 60034-31:2010, prepared by IEC TC 2, Rotating

machinery, was submitted to the formal vote and was approved by CENELEC as CLC/TS 60034-31 on

2011-02-21.

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) 2011-08-21
Annex ZA has been added by CENELEC.
__________
Endorsement notice

The text of the Technical Specification IEC/TS 60034-31:2010 was approved by CENELEC as a

Technical Specification without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards indicated:

IEC 60034-2-1:2007 NOTE Harmonized as EN 60034-2-1:2007 (not modified).
IEC 60034-12 NOTE Harmonized as EN 60034-12.
IEC/TS 60034-17 NOTE Harmonized as CLC/TS 60034-17.
IEC/TS 60034-25 NOTE Harmonized as CLC/TS 60034-25.
IEC 60034-26 NOTE Harmonized as EN 60034-26.
IEC 60079-0 NOTE Harmonized as EN 60079-0.
IEC 60300-3-3 NOTE Harmonized as EN 60300-3-3.
IEC 61241-1 NOTE Harmonized as EN 61241-1.
IEC 61800-2 NOTE Harmonized as EN 61800-2.
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SIST-TS CLC/TS 60034-31:2011
- 3 - CLC/TS 60034-31:2011
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 60034-1 (mod) - Rotating electrical machines - EN 60034-1 -
Part 1: Rating and performance
IEC 60034-30 - Rotating electrical machines - EN 60034-30 -
Part 30: Efficiency classes of single-speed,
three-phase, cage-induction motors (IE code)
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SIST-TS CLC/TS 60034-31:2011
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SIST-TS CLC/TS 60034-31:2011
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
CODE PRIX
ICS 29.160 ISBN 978-2-88910-023-1
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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SIST-TS CLC/TS 60034-31:2011
– 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

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SIST-TS CLC/TS 60034-31:2011
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 motors ................12

Table 2 – Exemplary efficiency calculation of a motor when operated at 50 Hz and

60 Hz with the same torque, using a 50 Hz motor rating as the basis....................................18

Table 3 – Loss distribution for low-voltage U-converters .......................................................21

Table 4 – Example of changing of efficiency, speed and torque demand with energy

efficiency class of three 11 kW, 50 Hz motors in the same application ..................................27

Table 5 – Average lifecycles for electric motors ....................................................................30

Table A.1 – Interpolation coefficients ....................................................................................35

Table A.2 – Nominal limits (%) for super-premium efficiency (IE4) ........................................35

Table A.3 – Standard power in kW associated with torque and speed for line-operated

motors ..................................................................................................................................36

Table A.4 – Nominal limits for super-premium efficiency (IE4) for 50 Hz line operated

motors ..................................................................................................................................37

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SIST-TS CLC/TS 60034-31:2011
– 4 – TS 60034-31 © IEC:2010

Table A.5 – Nominal limits for super-premium efficiency (IE4) for 60 Hz line operated

motors ..................................................................................................................................38

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SIST-TS CLC/TS 60034-31:2011
TS 60034-31 © IEC:2010 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –
Part 31: Selection of energy-efficient motors including
variable speed applications – Application guide
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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

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 60034-31, which is a technical specification, has been prepared by IEC technical

committee 2: Rotating machinery.
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SIST-TS CLC/TS 60034-31:2011
– 6 – TS 60034-31 © IEC:2010
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
2/1575/DTS 2/1594/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 the IEC 60034 series, published under the general title Rotating electrical

machines, can be found on the IEC website.

NOTE A table of cross-references of all IEC TC 2 publications can be found in the IEC TC 2 dashboard on the

IEC website.

The committee has decided that the contents of this publication will remain unchanged until

the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data

related to the specific publication. At this date, the publication will be be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct

understanding of its contents. Users should therefore print this document using a

colour printer.
---------------------- Page: 12 ----------------------
SIST-TS CLC/TS 60034-31:2011
TS 60034-31 © IEC:2010 – 7 –
INTRODUCTION

The present technical specification gives technical guidelines for the application of energy-

efficient motors in constant-speed and variable speed applications. It does not cover aspects

of a purely commercial nature.

Standards developed by IEC technical committee 2 do not deal with methods of how to obtain

a high efficiency but with tests to verify the guaranteed value. IEC 60034-2-1 is the most

important standard for this purpose.

For approximately 15 years regional agreements were negotiated in many areas of the world

regarding efficiency classes of three-phase, cage-induction motors with outputs up to about

200 kW maximum, as motors of this size are installed in high quantities and are for the most

part produced in series production. The design of these motors is often driven by the market

demand for low investment cost, hence energy efficiency was not a top priority.

In IEC 60034-30, IE efficiency classes for single-speed cage-induction motors have been

defined and test procedures specified:
IE1 Standard efficiency
IE2 High efficiency
IE3 Premium efficiency
IE4 Super-premium efficiency

Determination of efficiency for motors powered by a frequency converter will be included in

IEC standard 60034-2-3.

However, for motors rated 1 MW and above, which are usually custom made, a high efficiency

has always been one of the most important design goals. The full-load efficiency of these

machines typically ranges between 95 % and 98 %. Efficiency is usually part of the purchase

contract and is penalized if the guaranteed values are not met. Therefore, these higher

ratings are of secondary importance when assigning efficiency classes.

With permission from the National Electrical Manufacturers Association (NEMA), some parts

of this TS are based on NEMA MG 10, Energy Management Guide For Selection and Use of

Fixed Frequency Medium AC Squirrel-Cage Polyphase Induction Motors.
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SIST-TS CLC/TS 60034-31:2011
– 8 – TS 60034-31 © IEC:2010
ROTATING ELECTRICAL MACHINES –
Part 31: Selection of energy-efficient motors including
variable speed applications – Application guide
1 Scope

This part of IEC 60034 provides a guideline of technical aspects for the application of energy-

efficient, three-phase, electric motors. It not only applies to motor manufacturers, OEMs

(original equipment manufacturers), end users, regulators and legislators but to all other

interested parties.

This technical specification is applicable to all electrical machines covered by IEC 60034-30.

Most of the information however is also relevant for cage-induction machines with output

powers exceeding 375 kW.
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 60034-1, Rotating electrical machines – Part 1: Rating and performance

IEC 60034-30, Rotating electrical machines – Part 30: Efficiency classes of single-speed

three-phase, cage induction motors (IE-code)
3 Terms, definitions and symbols
3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 60034-1 and in

IEC 60034-30 apply.
3.2 Symbols
η is the nominal efficiency, %
η is the rated efficiency, %
f is the rated frequency, Hz
n is the rated speed, min
P is the rated output power, kW
T is the rated output torque, Nm
U is the rated voltage, V
---------------------- Page: 14 ----------------------
SIST-TS CLC/TS 60034-31:2011
TS 60034-31 © IEC:2010 – 9 –
4 General
Mechanical Energy
Electrical
Factory
Application
components
components recovery
automation
Proper and regular maintenance
Energy efficiency
Energy efficient, Variable speed
Most efficient
motors
gearboxes, bolts, … drive systems
power supply
Energy efficient Reducing elect. Low-energy
Power factor
pumps, fans, transmission mode during
correction devices
compressors, … losses standstill
Use most economical
components
Regenerative
Variable speed
Most efficient
braking
drive systems
power supply
Soft-start Minimize
with frequency rotating
DC-link coupling
control inertia
Low-energy
Optimized mass
Batteries
mode during
and flow
ultra-cap,
standstill
fly-wheels etc…
IEC 700/10
Figure 1 – Overview of different areas for savings of electrical energy
with drive systems

Energy can be saved in different areas of electrical drive systems depending on the duty type

(continuous or intermittent).

In continuous duty applications, improved efficiency of the electrical motor is beneficial. An

improved power factor (frequency converter, synchronous motor) can help reduce I²R losses

in cables. Mechanical optimizations (gearbox, belts, pumps, fans, etc.) may lead to much

greater savings than improvements of the electrical motor.

The application should also be regarded as well because, in many cases, the main part of the

energy saving can be obtained by managing the application load from the system point of

view. For that purpose, a demand-oriented speed control is often helpful.

Proper maintenance is usually beneficial. Many industrial plants have a high energy

consumption within the low voltage control circuits (typically 24 V power supply). Therefore,

high-efficiency low-voltage power supplies should be used. If possible, the factory should also

be shut down during long standstill periods (weekends, holidays).
S3…S10
S2 S1
Intermittent duty
Short-time Continuous duty
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SIST-TS CLC/TS 60034-31:2011
– 10 – TS 60034-31 © IEC:2010
10 000
IE2-Motor
IE3-Motor
IE2-Motor+converter
IE3-Motor+converter
IE2-Motor+converter+brake coil
1 000
100
1,1 11 110
Rated output power (kW)
IEC 701/10
Figure 2 – Typical losses of energy-efficient motors, converters
and electro-mechanical brakes

Figure 2 gives an overview of typical losses of energy-efficient motors and typical losses for

the power drive system including motors with voltage-source frequency converters with and

without brake coils of electro-mechanical motor brakes.

In intermittent duty applications, energy efficient motors are not very effective and may even

use more energy due to their increased inertia and start-up currents. For these applications,

the energy consumption during the starting phase can be reduced by ramping with a

frequency converter. Intermediate energy storage may be beneficial when the operating cycle

includes frequent regenerative braking phases (for example hoist drives, lifts, cranes etc.).

5 Efficiency
5.1 General

Motor efficiency is a measure of the effectiveness with which electrical energy is converted to

...

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