IEC TS 62933-3-3:2022

IEC TS 62933-3-3
®

Edition 1.0 2022-11
TECHNICAL
SPECIFICATION

colour
inside


Electrical energy storage (EES) systems –
Part 3-3: Planning and performance assessment of electrical energy storage
systems – Additional requirements for energy intensive and backup power
applications
IEC TS 62933-3-3:2022-11(en)

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IEC TS 62933-3-3

®


Edition 1.0 2022-11




TECHNICAL



SPECIFICATION








colour

inside










Electrical energy storage (EES) systems –

Part 3-3: Planning and performance assessment of electrical energy storage

systems – Additional requirements for energy intensive and backup power

applications
























INTERNATIONAL

ELECTROTECHNICAL


COMMISSION





ICS 13.020.30 ISBN 978-2-8322-6007-4




  Warning! Make sure that you obtained this publication from an authorized distributor.


® Registered trademark of the International Electrotechnical Commission

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– 2 – IEC TS 62933-3-3:2022  IEC 2022
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, abbreviated terms and symbols . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms and symbols . 10
3.2.1 Abbreviated terms . 10
3.2.2 Symbols . 11
4 General planning and performance assessment considerations for EES systems . 11
5 Peak shaving and load levelling . 11
5.1 Application of EES system . 11
5.1.1 Functional purpose . 11
5.1.2 Applications related requirements . 11
5.2 Conditions and requirements for connection to the grid . 11
5.3 Design of the EES systems . 12
5.3.1 Structure of the EES systems . 12
5.3.2 Subsystem specification and requirements . 12
5.3.3 Grid integration of the EES systems . 12
5.3.4 Operation and control . 12
5.3.5 Monitoring . 15
5.3.6 Maintenance . 15
5.3.7 Communication interface . 15
5.4 Sizing and resulting parameters of the EES system . 16
5.4.1 Sizing . 16
5.4.2 Characteristics and restrictions of the EES system . 17
5.5 Service life of the EES system . 17
5.5.1 Installation . 17
5.5.2 Performance assessment . 17
5.5.3 Operation and control . 18
5.5.4 Monitoring . 21
5.5.5 Maintenance . 21
6 Islanded grid application . 21
6.1 Application of the EES system . 21
6.1.1 Functional purpose . 21
6.1.2 Applications related requirements . 21
6.2 Conditions and requirements for connection to the grid . 21
6.2.1 Grid parameters at the intended POC . 21
6.2.2 Service conditions . 21
6.2.3 Requirements and restrictions of the grid or system operator . 21
6.2.4 Standards and local regulations . 21
6.3 Design of the EES system . 22
6.3.1 Structure of the EES system . 22
6.3.2 Subsystem specifications . 23
6.3.3 Grid integration of the EES system . 23
6.3.4 Operation and control . 23

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IEC TS 62933-3-3:2022  IEC 2022 – 3 –
6.3.5 Monitoring . 24
6.3.6 Maintenance . 24
6.3.7 Communication interface . 24
6.4 Sizing and resulting parameters of the EES system . 24
6.4.1 Sizing . 24
6.4.2 Characteristics and restrictions of the EES system . 26
6.5 Service life of the EES system . 26
6.5.1 Installation . 26
6.5.2 Performance assessment . 26
6.5.3 Operation and control . 26
6.5.4 Monitoring . 27
6.5.5 Maintenance . 27
7 Backup power supply and emergency support . 28
7.1 Applications of the EES system. 28
7.1.1 Functional purpose of the EES system. 28
7.1.2 Applications related requirements . 28
7.2 Conditions and requirements for connection to the grid . 28
7.3 Design of the EES system . 28
7.3.1 Structure of the EES systems . 28
7.3.2 Subsystem specifications and requirements . 28
7.3.3 Grid integration of the EES system . 28
7.3.4 Operation and control . 32
7.3.5 Monitoring . 32
7.3.6 Maintenance . 32
7.3.7 Communication interface . 32
7.4 Sizing and resulting parameters of the EES system . 33
7.4.1 Sizing . 33
7.4.2 Characteristics and restrictions of the EES system . 34
7.5 Service life of the EES system . 34
7.5.1 Installation . 34
7.5.2 Performance assessment . 35
7.5.3 Operation and control . 35
7.5.4 Monitoring . 39
7.5.5 Maintenance . 39
Annex A (informative) Technology dependent requirements for grid interconnection
scheme . 40
Annex B (informative) Specific requirements for battery-based EES systems . 44
Bibliography . 46

Figure 1 – An example of peak shaving and fluctuation reduction of consumption
consisting of charge and discharge events . 13
Figure 2 – One charge and one discharge duty cycle for peak shaving application . 14
Figure 3 – Two charges and two discharges duty cycle for peak shaving application. 15
Figure 4 – Use case for information exchange between grid and EES system . 16
Figure 5 – Process to determine the sizing and planning of the EES system applied in
peak shaving and fluctuation reduction of consumption applications . 17
Figure 6 – Sequence of charging events in peak shaving application . 19
Figure 7 – Sequence of discharging events in peak shaving application . 20

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– 4 – IEC TS 62933-3-3:2022  IEC 2022
Figure 8 – Example configuration for applying an EES system to an islanded grid
containing distributed energy resources . 23
Figure 9 – Example process to determine the sizing and planning of EES system

applied in islanded grid application . 25
Figure 10 – Example use case for backup power using a diesel generator . 29
Figure 11 – Simple replacement of diesel generator with EES system for backup power
support . 30
Figure 12 – EES system use case for both backup power and EES’s own functions . 31
Figure 13 – EES system use case for communication with distribution panel . 32
Figure 14 – Example process to determine the sizing and planning of the EES system
applied to the backup power supply and emergency support application . 33
Figure 15 – Example operation flow for backup power support during grid outage . 36
Figure 16 – Example operation flow for backup power support when grid is recovered . 36
Figure 17 – Example of configuration for low voltage connection . 38
Figure 18 – Example of configuration for high voltage connection . 39
Figure A.1 – Grounded Y-Δ (GY-Δ) interconnection between grid and EES system . 40
Figure A.2 – Grounded Y-grounded Y (GY-GY) interconnection between grid and EES

system . 41
Figure A.3 – Δ-grounded Y (Δ-GY) interconnection between grid and EES system . 42
Figure A.4 – Non-transformer direct interconnection between grid and EES system . 43

Table 1 – Operation modes of EES system for peak shaving and fluctuation reduction
of consumption . 12
Table 2 – Conditions for charging/discharging limitation . 21
Table 3 – Example of the operation time for emergency load facilities. 34
Table A.1 – Pros and cons of grounded Y-Δ (GY-Δ) interconnection scheme . 41
Table A.2 – Pros and cons of grounded Y-grounded Y (GY-GY) interconnection
scheme . 42
Table A.3 – Pros and cons of Δ-grounded Y (Δ-GY) interconnection scheme . 43
Table A.4 – Pros and cons of non-transformer direct interconnection scheme . 43
Table B.1 – BMS data monitored by PMS . 45
Table B.2 – PCS data monitored by PMS . 45
Table B.3 – PCS controls sent by PMS . 45

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IEC TS 62933-3-3:2022  IEC 2022 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ELECTRICAL ENERGY STORAGE (EES) SYSTEMS –

Part 3-3: Planning and performance assessment of electrical energy
storage systems – Additional requirements for energy intensive and
backup power applications

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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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.
IEC TS 62933-3-3 has been prepared by IEC technical committee 120: Electrical Energy
Storage (EES) Systems. It is a Technical Specification.
The text of this Technical Specification is based on the following documents:
Draft Report on voting
120/262/DTS 120/275/RVDTS

Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this Technical Specification is English.

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– 6 – IEC TS 62933-3-3:2022  IEC 2022
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 62933 series, published under the general title Electrical energy
storage (EES) systems, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The "colour inside" logo on the cover page of this document 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.

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IEC TS 62933-3-3:2022  IEC 2022 – 7 –
INTRODUCTION
Electrical energy storage (EES) systems can provide solutions to multiple energy storage
scenarios. The objective of this document is to provide requirements, guidelines and references
when EES systems are designed, controlled and operated for energy intensive, islanded grid
and backup power supply applications.

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– 8 – IEC TS 62933-3-3:2022  IEC 2022
ELECTRICAL ENERGY STORAGE (EES) SYSTEMS –

Part 3-3: Planning and performance assessment of electrical energy
storage systems – Additional requirements for energy intensive and
backup power applications



1 Scope
This part of IEC 62933 provides requirements, guidelines and references when EES systems
are designed, controlled and operated for energy intensive, islanded grid and backup power
supply applications. In energy intensive applications, the EES system provides long charge and
discharge phases at variable powers to the supported grid or user equipment. In islanded
operation, the EES system provides energy to the islanded grid and coordinates other power
generation systems in the islanded grid. In backup power supply and emergency support, the
EES system provides energy to the internal grid or a set of emergency loads when the main
grid power supply is not available.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 61850-7-420, Communication networks and systems for power utility automation – Part 7–
420: Basic communication structure – Distributed energy resources and distribution automation
logical nodes
IEC TR 61850-90-9, Communication networks and systems for power utility automation –
Part 90-9: Use of IEC 61850 for Electrical Energy Storage Systems
IEC 62933-1:2018, Electrical energy storage (EES) systems – Part 1: Vocabulary
IEC 62933-2-1, Electrical energy storage (EES) systems – Part 2-1: Unit parameters and testing
methods – General specification
IEC TS 62933-2-2, Electrical energy storage (EES) systems – Part 2-2: Unit parameters and
testing methods – Application and performance testing
IEC TS 62933-3-1:2018, Electrical energy storage (EES) systems – Part 3-1: Planning and
performance assessment of electrical energy storage systems – General specification
IEC TS 62933-3-2:2022, Electrical energy storage (EES) systems – Part 3-2: Planning and
performance assessment of electrical energy storage systems – Additional requirements for
power intensive and renewable energy sources integration related applications
3 Terms, definitions, abbreviated terms and symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62933-1 and the
following apply.

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IEC TS 62933-3-3:2022  IEC 2022 – 9 –
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/;
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
backup power supply
provision of power to all internal loads connected to user side equipment during a specified time
period without relying on an external power source in the event of electrical grid outage
3.1.2
black start capability
capability of the EES system to start the electric power system (IEV 601-01-01) only with
internal energy resources
3.1.3
allowed charging time
time period when an EES system is allowed to charge the accumulation subsystem in the peak
shaving application
3.1.4
allowed discharging time
time period when an EES system is allowed to discharge the accumulation subsystem in the
peak shaving application
3.1.5
duty cycle roundtrip efficiency
energy discharged measured at the primary POC divided by the energy absorbed by the EES
system, as a sum of what is measured at all the POCs (primary and auxiliary), during duty
cycles in a specified operating mode at continuous operating conditions with the same final
state of charge as the initial state of charge
[SOURCE: IEC 62933-1:2018, 4.12.1, modified – the notes have been deleted.]
3.1.6
emergency load
set of devices and equipment that should be operated during electrical grid outage
3.1.7
emergency support
provision of power to emergency loads within a specified time and duration without relying on
an external power source in the event of electrical grid outage
3.1.8
energy intensive application
EES system application generally not very demanding in terms of step response performances
but with long charge and discharge phases at variable powers
[SOURCE: IEC 62933-1:2018, 3.12, modified – the terms “long duration application” and “long
term application” have been deleted and the notes have been deleted.]
3.1.9
fluctuation reduction of consumption
reduction of power oscillation of power consumption at the grid connection point by absorbing
the active power of the grid by EES systems at low power demand phases and by feeding in
additional active power by EES systems at high power demand phases

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– 10 – IEC TS 62933-3-3:2022  IEC 2022
3.1.10
islanded grid
part of an electric power system that is electrically disconnected from the remainder of the
interconnected electric power system but remains energized from the local electric power
sources
3.1.11
islanded operation
function to provide power to the islanded grid and to control the coordination with other power
generation systems and the system voltage and frequency
3.1.12
load profile
line graph illustrating the variation in loads over a specific time
3.1.13
peak shaving
limitation of the power consumption from the power grid to a maximum value by providing the
power exceeding the maximum value from other active power sources
3.1.14
rated AC current
AC current that the EES system can provide to the grid continuously and can accept from the
grid continuously without exceeding the maximum operating temperature of the EES system
3.1.15
self-discharge
phenomenon by which the EES system accumulation subsystem loses energy in other ways
than by discharge through the primary POC
[SOURCE: IEC 62933-1:2018, 4.12.7, modified – the note has been deleted.]
3.2 Abbreviated terms and symbols
3.2.1 Abbreviated terms
ACB air circuit breaker
ATS automatic transfer switch
BMS battery management system
CVCF constant voltage constant frequency
...