IEC TS 62933-2-2:2022

IEC TS 62933-2-2 ®
Edition 1.0 2022-04
TECHNICAL
SPECIFICATION
colour
inside
Electrical energy storage (EES) systems –
Part 2-2: Unit parameters and testing methods – Application and performance
testing
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IEC TS 62933-2-2 ®
Edition 1.0 2022-04
TECHNICAL
SPECIFICATION
colour
inside
Electrical energy storage (EES) systems –

Part 2-2: Unit parameters and testing methods – Application and performance

testing
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.020.30 ISBN 978-2-8322-1104-1

– 2 – IEC TS 62933-2-2:2022 © IEC 2022
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms . 9
4 Application of EES system . 9
4.1 General . 9
4.2 Class A applications . 9
4.2.1 Frequency control . 9
4.2.2 Primary/secondary/tertiary frequency control . 9
4.2.3 Fluctuation reduction of PV and wind farms . 10
4.2.4 Reactive-power voltage control . 10
4.2.5 Voltage sag mitigation . 10
4.3 Class B applications . 10
4.3.1 Peak shaving . 10
4.3.2 Renewable firming . 10
4.3.3 Islanded grid . 11
4.4 Class C applications . 11
5 Parameter testing methods for application . 11
5.1 Parameter tests . 11
5.1.1 General . 11
5.1.2 Actual energy capacity . 11
5.1.3 Roundtrip efficiency . 11
5.1.4 Step response time and ramp rate . 12
5.1.5 Auxiliary power consumption . 12
5.1.6 Self-discharge . 12
5.1.7 SOC . 12
5.2 Duty cycle performance tests . 12
5.2.1 General . 12
5.2.2 Duty cycle roundtrip efficiency . 12
5.2.3 Reference signal tracking . 12
5.3 Test items for each application . 14
6 Duty cycle for specific applications . 15
6.1 General . 15
6.2 Frequency control . 15
6.2.1 Frequency control duty cycle . 15
6.2.2 Primary/secondary/tertiary frequency control duty cycle . 16
6.2.3 Deviation control of frequency . 18
6.3 Fluctuation reduction of PV and wind farm . 20
6.4 Reactive-power voltage control . 22
6.5 Voltage sag mitigation . 23
6.6 Peak shaving . 26
6.6.1 “One charge-one discharge” mode . 26
6.6.2 “Two charges-two discharges” mode . 28

6.7 Renewable firming . 29
6.8 Islanded grid . 30
6.9 Back-up power . 32
6.9.1 General . 32
6.9.2 Grid outage test . 32
6.9.3 Step load test . 32
6.9.4 Unbalanced load test . 33
6.9.5 Function test . 33
6.9.6 Grid recovery test . 33
Annex A (normative)  Numerical data for duty cycle . 34
Bibliography . 66

Figure 1 – Frequency control duty cycle . 16
Figure 2 – Primary frequency control signal – 24 h duty cycle with 30 s discharge
every half hour shown over a) 24 h and b) 2 h . 17
Figure 3 – Secondary frequency control signal – 24 h duty cycle with 20 min discharge
every hour shown over a) 24 h and b) 3 h . 18
Figure 4 – Example of droop active power frequency control with a dead band . 19
Figure 5 – Duty cycle of fluctuation reduction of PV (photovoltaic energy systems) . 20
Figure 6 – Duty cycle of fluctuation reduction of wind farm . 21
Figure 7 – Duty cycle of fluctuation reduction of wind farm (low standard deviation) . 21
Figure 8 – Duty cycle of fluctuation reduction of wind farm (average standard
deviation) . 22
Figure 9 – Duty cycle of fluctuation reduction of wind farm (high standard deviation) . 22
Figure 10 – Reactive-power voltage control test profile . 23
Figure 11 – Voltage sag mitigation test profile (test level: 80 %) . 24
Figure 12 – Voltage sag mitigation test profile (test level: 70 %) . 25
Figure 13 – Voltage sag mitigation test profile (test level: 40 %) . 25
Figure 14 – Voltage sag mitigation test profile (test level: 0 %) . 26
Figure 15 – Duty cycle for peak shaving application of “one charge-one discharge”
mode . 28
Figure 16 – Duty cycle for peak shaving of “two charges-two discharges” mode . 29
Figure 17 – Duty cycle for renewable firming mode . 30
Figure 18 – Duty cycle for fluctuation reduction of renewable energy sources (power)
and frequency control . 31
Figure 19 – Duty cycle for fluctuation reduction of renewable energy sources (power)
without frequency control . 31
Figure 20 – Duty cycle without fluctuation reduction of renewable energy sources
(power) or frequency control . 32

Table 1 – Test items for each application . 15
Table 2 – Reactive-power voltage control test profile . 23
Table A.1 – Numerical data of Figure 1 (duty cycle of frequency control ) . 35
Table A.2 – Numerical data of Figure 5 (duty cycle of fluctuation reduction of PV
(photovoltaic energy systems) ) . 40
Table A.3 – Numerical data of Figure 7 (duty cycle of fluctuation reduction of wind
farm (low standard deviation)) . 44

– 4 – IEC TS 62933-2-2:2022 © IEC 2022
Table A.4 – Numerical data of Figure 8 (duty cycle of fluctuation reduction of wind
farm (average standard deviation)) . 45
Table A.5 – Numerical data of Figure 9 (duty cycle of fluctuation reduction of wind

farm (high standard deviation)) . 46
Table A.6 – Numerical data of Figure 17 (duty cycle for renewable firming mode) . 47
Table A.7 – Numerical data of Figure 18 (duty cycle for fluctuation reduction of
renewable energy sources (power) and frequency control) .
...