IEC TS 62933-5-1:2017

IEC TS 62933-5-1 ®
Edition 1.0 2017-07
TECHNICAL
SPECIFICATION
colour
inside
Electrical energy storage (EES) systems –
Part 5-1: Safety considerations for grid-integrated EES systems – General
specification
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IEC TS 62933-5-1 ®
Edition 1.0 2017-07
TECHNICAL
SPECIFICATION
colour
inside
Electrical energy storage (EES) systems –

Part 5-1: Safety considerations for grid-integrated EES systems – General

specification
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.020.30 ISBN 978-2-8322-4565-1

– 2 – IEC TS 62933-5-1:2017  IEC 2017
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Basic guidelines for safety aspects of EES systems . 17
5 Hazard considerations for EES systems . 17
5.1 Electrical hazards . 17
5.2 Mechanical hazards . 18
5.3 Other hazards . 19
5.3.1 Explosion hazards . 19
5.3.2 Hazards arising from electrical, magnetic, and electromagnetic fields . 19
5.3.3 Fire hazards . 19
5.3.4 Temperature hazards . 21
5.3.5 Chemical hazards . 21
5.3.6 Unsuitable working conditions. 22
6 EES system risk assessment . 22
6.1 EES system structure. 22
6.1.1 General characteristics . 22
6.1.2 Specific characteristics . 22
6.2 Description of storage conditions . 23
6.2.1 Types of grids . 23
6.2.2 Type of applications . 23
6.2.3 Location . 23
6.2.4 Vulnerable elements . 24
6.2.5 Special provisions for EES systems in generally accessible locations . 24
6.2.6 Sources of external aggression . 24
6.2.7 Unattended operation . 24
6.2.8 Unintentional islanding . 24
6.3 Risk analysis. 25
6.3.1 General . 25
6.3.2 Risk considerations . 26
6.3.3 System level risk analysis . 27
7 Requirements necessary to reduce risks . 27
7.1 General measures to reduce risks . 27
7.2 Preventive measures against damage to neighbouring inhabitants . 29
7.3 Preventive measures against damage to workers and residents . 30
7.3.1 Protection from electrical hazards . 30
7.3.2 Protection from mechanical hazards . 31
7.3.3 Protection from other hazards . 31
7.4 Over current protection design . 34
7.5 EES system disconnection and shutdown . 35
7.5.1 General . 35
7.5.2 Grid-disconnected state . 36

7.5.3 Stopped state . 36
7.5.4 EES system shutdown . 36
7.5.5 Cyber security . 37
7.5.6 Partial disconnection . 37
7.5.7 Equipment guidelines for emergency shutdown . 37
7.6 Preventive maintenance . 38
7.7 Staff training . 38
7.8 Safety design . 39
7.8.1 General . 39
7.8.2 Initial safety design and subsequent design revision . 39
7.8.3 Design revision for minor and major system changes . 40
8 System testing . 40
8.1 General . 40
8.2 Auxiliary system malfunction . 42
8.3 EES control subsystem malfunction . 42
8.4 EES system internal communication malfunction. 42
8.5 EES system external communication malfunction . 43
9 Guidelines and manuals . 43
Annex A (informative) Main risks of different storage technologies . 45
A.1 Pumped hydro storage . 45
A.2 Flywheel . 45
A.3 Secondary batteries . 46
A.4 Hydrogen and synthetic natural gas . 47
A.5 Other EES system technologies . 48
Bibliography . 49

Figure 1 – General description of the approach to address hazards in EES systems . 17
Figure 2 – Islanding of the EES system . 25
Figure 3 – Iterative checking sequence in general risk assessment procedures . 28
Figure 4 – General risk reduction measures to minimize hazards . 29
Figure 5 – Damage propagation from an incident to a big accident, and layered
measures to minimize damages . 29
Figure 6 – Examples of different EES system architectures. 36
Figure 7 – Initial safety design and design revision . 39
Figure 8 – EES system architecture in the two main EESS configurations . 41

Table A.1 – Main risk scenarios for pumped hydro storage . 45
Table A.2 – Main risk scenarios for flywheel . 46
Table A.3 – Example of main risk scenarios for lithium-ion batteries . 47
Table A.4 – Main risk scenarios for hydrogen storage . 48

– 4 – IEC TS 62933-5-1:2017  IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL ENERGY STORAGE (EES) SYSTEMS –

Part 5-1: Safety considerations for grid-integrated EES systems –
General specification
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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consensus of opinion on the relevant subjects since each technical com
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