IEC 61683:1999

Photovoltaic systems - Power conditioners - Procedure for measuring efficiency

IEC 61683:1999 Describes guidelines for measuring the efficiency of power conditioners used in stand-alone and utility-interactive photovoltaic systems, where the output of the power conditioner is a stable a.c. voltage of constant frequency or a stable d.c. voltage.

Systèmes photovoltaïques - Conditionneurs d’énergie électrique - Procédure de mesure du rendement

IEC 61683:1999 décrit les lignes directrices pour mesurer le rendement des conditionneurs d'énergie électrique utilisés dans les systèmes photovoltaïques autonomes et interactifs avec le réseau, avec lesquels la sortie du conditionneur d'énergie électrique est une tension alternative stable de fréquence constante ou une tension continue stable.

General Information

• Status: Published
• Publication Date: 24-Nov-1999
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 27.160 - Solar energy engineering
• Technical Committee: TC 82 - Solar photovoltaic energy systems
• Drafting Committee: WG 3 - TC 82/WG 3
• Current Stage: PPUB - Publication issued
• Start Date: 15-Dec-1999
• Completion Date: 25-Nov-1999

Standards Content (Sample)

INTERNATIONAL
IEC
STANDARD
First edition
1999-11
Photovoltaic systems –
Power conditioners –
Procedure for measuring efficiency
Systèmes photovoltaïques –
Conditionneurs de puissance –
Procédure de mesure du rendement
Reference number
Numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series.
Consolidated publications
Consolidated versions of some IEC publications including amendments are
available. For example, edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the
base publication, the base publication incorporating amendment 1 and the base
publication incorporating amendments 1 and 2.
Validity of this publication
The technical content of IEC publications is kept under constant review by the IEC,
thus ensuring that the content reflects current technology.
Information relating to the date of the reconfirmation of the publication is available
in the IEC catalogue.
Information on the subjects under consideration and work in progress undertaken by
the technical committee which has prepared this publication, as well as the list of
publications issued, is to be found at the following IEC sources:
• IEC web site*
• Catalogue of IEC publications
Published yearly with regular updates
(On-line catalogue)*
• IEC Bulletin
Available both at the IEC web site* and as a printed periodical
Terminology, graphical and letter symbols
For general terminology, readers are referred to IEC 60050: International
Electrotechnical Vocabulary (IEV).
For graphical symbols, and letter symbols and signs approved by the IEC for
general use, readers are referred to publications IEC 60027: Letter symbols to be
used in electrical technology, IEC 60417: Graphical symbols for use on equipment.
Index, survey and compilation of the single sheets and IEC 60617: Graphical symbols
for diagrams.
* See web site address on title page.

INTERNATIONAL
IEC
STANDARD
First edition
1999-11
Photovoltaic systems –
Power conditioners –
Procedure for measuring efficiency
Systèmes photovoltaïques –
Conditionneurs de puissance –
Procédure de mesure du rendement
 IEC 1999  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
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R
International Electrotechnical Commission
For price, see current catalogue

– 2 – 61683 © IEC:1999(E)
CONTENTS
Page
FOREWORD . 3
INTRODUCTION .4
Clause
1 Scope . 5
2 Normative reference . 5
3 Definitions. 5
4 Efficiency measurement conditions . 6
4.1 DC power source for testing. 6
4.2 Temperature . 6
4.3 Output voltage and frequency . 6
4.4 Input voltage. 7
4.5 Ripple and distortion. 7
4.6 Resistive loads/utility grid . 7
4.7 Reactive loads . 7
4.8 Resistive plus non-linear loads . 8
4.9 Complex loads . 8
5 Efficiency calculations. 8
5.1 Rated output efficiency . 8
5.2 Partial output efficiency. 8
5.3 Energy efficiency . 9
5.4 Efficiency tolerances. 9
6 Efficiency test circuits . 9
6.1 Test circuits . 9
6.2 Measurement procedure . 10
7 Loss measurement. 10
7.1 No-load loss . 10
7.2 Standby loss . 11
Annex A (informative) Power conditioner description . 12
Annex B (informative) Power efficiency and conversion factor . 14
Annex C (informative) Weighted-average energy efficiency . 16
Annex D (informative) Derivation of efficiency tolerance in table 2. 19
Bibliography . 20

61683 © IEC:1999(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PHOTOVOLTAIC SYSTEMS – POWER CONDITIONERS –
PROCEDURE FOR MEASURING EFFICIENCY
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61683 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
The text of this standard is based on the following documents:
FDIS Report on voting
82/229/FDIS 82/233/RVD
Full information on the voting for the approval of this standard 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 3.
Annexes A, B, C and D are for information only.
A bilingual version of this standard may be issued at a later date.
The committee has decided that this publication remains valid until 2003. At this date, in
accordance with the committee’s decision, the publication will be
reconfirmed;
withdrawn;
replaced by a revised edition, or
amended.
– 4 – 61683 © IEC:1999(E)
INTRODUCTION
Among the principal characteristics of power conditioners, efficiency is considered as an
important factor. A standardized procedure for measuring the efficiency of power conditioners
is necessary for their widespread use in photovoltaic systems by increasing the reliability of
their claimed efficiency.
Generally speaking, power conditioner efficiency is affected by the following parameters:
– power level;
– input voltage;
– output voltage;
– power factor;
– harmonic content;
– load non-linearity;
– temperature.
These parameters are considered to be included in the test condition of this standard
explicitly or implicitly.
The purpose of this standard is to provide the means to evaluate the intrinsic efficiency of
power conditioners by a direct measurement of input and output power in the factory.
Therefore, indirect items such as maximum power-point tracking accuracy are outside the
scope of this document. It is expected that those will be dealt with in future relevant IEC
standard(s).
61683 © IEC:1999(E) – 5 –
PHOTOVOLTAIC SYSTEMS – POWER CONDITIONERS –
PROCEDURE FOR MEASURING EFFICIENCY
1 Scope
This standard describes guidelines for measuring the efficiency of power conditioners used in
stand-alone and utility-interactive photovoltaic systems, where the output of the power conditioner
is a stable a.c. voltage of constant frequency or a stable d.c. voltage. The efficiency is
calculated from a direct measurement of input and output power in the factory. An isolation
transformer is included where it is applicable.
2 Normative reference
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this International Standard. For dated references, subsequent
amendments to, or revisions of, any of these publications do not apply. However, parties to
agreements based on this International Standard are encouraged to investigate the possibility
of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of IEC
and ISO maintain registers of currently valid International Standards.
IEC 60146-1-1:1991, Semiconductor convertors – General requirements and line commutated
convertors – Part 1-1: Specifications of basic requirements
3 Definitions
For the purposes of this standard, the following definitions apply. All efficiency definitions are
applied to electric power conversion alone and do not consider any heat production. The
above normative references contain other definitions.
In annex A, the definition of power conditioner is given. Power efficiency and conversion
factor are explained in annex B.
3.1
rated output efficiency
ratio of output power to input power when the power conditioner is operating at its rated
output
3.2
partial output efficiency
ratio of output power to input power when the power conditioner is operating below its rated
output
3.3
energy efficiency
ratio of output energy to input energy during an identified period

– 6 – 61683 © IEC:1999(E)
3.4
efficiency tolerance
permissible tolerance between the manufacturer's specified efficiency and the measured
efficiency
3.5
PV array simulator
simulator which has I-V characteristics equivalent to a PV array
3.6
no-load loss
input power of the power conditioner when its load is disconnected or its output power is zero
3.7
standby loss
for a utility interactive power conditioner, power drawn from the utility grid when the power
conditioner is in standby mode. For a stand-alone power conditioner, d.c. input power when
the power conditioner is in standby mode
3.8
maximum power point tracking (MPPT)
control strategy whereby the power conditioner input voltage is always at or near the
maximum power point of the PV array
4 Efficiency measurement conditions
Efficiency shall be measured under the matrix of conditions as described in the following
clauses and table 1. Specific conditions may be excluded by mutual agreement when those
conditions are outside the manufacturer's allowable operating range. The resulting data shall
be presented in tabular form and may also be presented graphically.
NOTE For example, stand-alone power conditioners are typically designed to handle short-term overload signifi-
cantly above the rated power. The test at 120 % of rated capacity is included to give an indication of the
performance of the power conditioner under these conditions. Some power conditioners are not designed to
provide more than their rated output and might be damaged if operated at 120 % of rated capacity. In such cases,
test documentation shall note that the test was excluded due to limitation in the power conditioner.
4.1 DC power source for testing
For power conditioners operating with fixed input voltage, the d.c. power source shall be a
storage battery or constant voltage power source to maint
...

IEC 61683 ®
Edition 1.0 1999-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Photovoltaic systems – Power conditioners – Procedure for measuring
efficiency
Systèmes photovoltaïques – Conditionneurs d’énergie électrique –
Procédure de mesure du rendement

Copyright © 1999 IEC, Geneva, Switzerland

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IEC 61683 ®
Edition 1.0 1999-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Photovoltaic systems – Power conditioners – Procedure for measuring

efficiency
Systèmes photovoltaïques – Conditionneurs d’énergie électrique –

Procédure de mesure du rendement

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-1092-2

– 2 – IEC 61683:1999 © IEC 1999
CONTENTS
FOREWORD . 3
INTRODUCTION . 4
1 Scope . 5
2 Normative reference . 5
3 Definitions . 5
4 Efficiency measurement conditions . 6
4.1 DC power source for testing . 6
4.2 Temperature . 6
4.3 Output voltage and frequency . 6
4.4 Input voltage . 7
4.5 Ripple and distortion . 7
4.6 Resistive loads/utility grid . 7
4.7 Reactive loads. 7
4.8 Resistive plus non-linear loads . 8
4.9 Complex loads . 8
5 Efficiency calculations . 8
5.1 Rated output efficiency . 8
5.2 Partial output efficiency . 8
5.3 Energy efficiency . 9
5.4 Efficiency tolerances . 9
6 Efficiency test circuits . 9
6.1 Test circuits . 9
6.2 Measurement procedure . 10
7 Loss measurement . 10
7.1 No-load loss . 10
7.2 Standby loss . 11

Annex A (informative) Power conditioner description. 12
Annex B (informative) Power efficiency and conversion factor. 14
Annex C (informative) Weighted-average energy efficiency . 16
Annex D (informative) Derivation of efficiency tolerance in table 2 . 19
Bibliography . 20

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PHOTOVOLTAIC SYSTEMS – POWER CONDITIONERS –
PROCEDURE FOR MEASURING EFFICIENCY

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61683 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
The text of this standard is based on the following documents:
FDIS Report on voting
82/229/FDIS 82/233/RVD
Full information on the voting for the approval of this standard 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 3.
Annexes A, B, C and D are for information only.
A bilingual version of this standard may be issued at a later date.
The committee has decided that this publication remains valid until 2003. At this date, in
accordance with the committee’s decision, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
– 4 – IEC 61683:1999 © IEC 1999
INTRODUCTION
Among the principal characteristics of power conditioners, efficiency is considered as an
important factor. A standardized procedure for measuring the efficiency of power conditioners
is necessary for their widespread use in photovoltaic systems by increasing the reliability of
their claimed efficiency.
Generally speaking, power conditioner efficiency is affected by the following parameters:
– power level;
– input voltage;
– output voltage;
– power factor;
– harmonic content;
– load non-linearity;
– temperature.
These parameters are considered to be included in the test condition of this standard
explicitly or implicitly.
The purpose of this standard is to provide the means to evaluate the intrinsic efficiency of
power conditioners by a direct measurement of input and output power in the factory.
Therefore, indirect items such as maximum power-point tracking accuracy are outside the
scope of this document. It is expected that those will be dealt with in future relevant IEC
standard(s).
PHOTOVOLTAIC SYSTEMS – POWER CONDITIONERS –
PROCEDURE FOR MEASURING EFFICIENCY

1 Scope
This standard describes guidelines for measuring the efficiency of power conditioners used in
stand-alone and utility-interactive photovoltaic systems, where the output of the power conditioner
is a stable a.c. voltage of constant frequency or a stable d.c. voltage. The efficiency is
calculated from a direct measurement of input and output power in the factory. An isolation
transformer is included where it is applicable.
2 Normative reference
The following normative documents contain provisions whi
...