IEC TS 63106-2:2022

IEC TS 63106-2 ®
Edition 1.0 2022-03
TECHNICAL
SPECIFICATION
colour
inside
Simulators used for testing of photovoltaic power conversion equipment –
Recommendations –
Part 2: DC power simulators
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IEC TS 63106-2 ®
Edition 1.0 2022-03
TECHNICAL
SPECIFICATION
colour
inside
Simulators used for testing of photovoltaic power conversion equipment –

Recommendations –
Part 2: DC power simulators
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-1093-5

– 2 – IEC TS 63106-2:2022 © IEC 2022
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 PCE types with respect to DC voltage levels . 10
4.1 General . 10
4.2 Module level PCE . 11
4.3 String level PCE . 11
4.4 Central PCE . 11
5 Test setup for utility interactive inverters . 11
5.1 General . 11
5.2 Test setup examples . 11
5.3 System configuration options . 12
5.3.1 General . 12
5.3.2 PV array . 12
5.3.3 PV array simulator. 13
5.3.4 DC power supply . 13
6 General recommendations for DC power simulator . 13
6.1 General . 13
6.2 DC output voltage accuracy and ripple . 14
6.3 I-V curve stability for EUT testing . 14
6.3.1 General . 14
6.3.2 DC irradiance change rate . 15
6.4 DC power simulator performance and characteristics for utility interaction tests . 16
6.5 Additional tests conducted with DC power simulators . 34
6.5.1 General . 34
6.5.2 PCE operational stability with sudden irradiance changes (due to
movement of sun between clouds) . 35
6.5.3 Automatic start and stop operation with gradual irradiance changes
(representing morning and evening conditions) . 36
6.5.4 PCE DC to AC power conversion efficiency measurement . 36
6.5.5 PCE maximum power point tracking efficiency measurement . 36
6.5.6 PCE total power conversion efficiency measurement . 37
6.6 Avoidance measures of transient impact to EUTs . 37
Annex A (informative) DC I-V curve dynamic accuracy against MPPT control . 38
A.1 General . 38
A.2 Example of DC I-V curve stability for MPPT properties . 38
A.2.1 MPPT control . 38
A.2.2 Recommended stability of operation on the I-V curve . 39
A.2.3 Recommended I-V curve resolution . 39
A.2.4 Use of DC power supply as an input of EUT . 39
Annex B (informative) DC power simulator stability against utility- frequency ripple
voltage/current . 41
B.1 General . 41
B.2 Example of twice the utility- frequency ripple voltage/current . 41
B.2.1 Twice the utility frequency ripple voltage/current . 41

IEC TS 63106-2:202 © IEC 2022 – 3 –
B.2.2 Stability of I-V curve for the DC ripple . 42
Annex C (informative) PV array simulator I-V curve stability against quick power change
in UVRT test . 44
C.1 General . 44
C.2 DC voltage/current shift by withdrawing power change in UVRT test . 44
Annex D (informative) DC I-V curve stability against low irradiance at sunrise and sunset . 47
D.1 General . 47
D.2 Example of a DC I-V curve stability against slow irradiance change rate in the
morning and evening – I-V curve with low irradiance periods and EUT input
voltage/current transition . 47
Annex E (informative) DC I-V curve behaviour in rapidly varying irradiance conditions . 49
E.1 General . 49
E.2 I-V curve response to varying irradiance . 49
E.2.1 Irradiance sudden change on I-V characteristics of the PV array (an
example) . 49
E.2.2 Recommendation of irradiance quick change rate for test of the EUT by PV
array simulator . 49
Bibliography . 52

Figure 1 – Examples of ports . 9
Figure 2 – Examples of fundamental setup of EUT test system . 12
Figure A.1 – Voltage and current swing by MPPT control on I-V curve around MPP. 38
Figure A.2 – Current and voltage swing by MPPT control on I-V curve below MPP . 39
Figure A.3 – Current and voltage swing by MPPT control on I-V characteristic curve of
DC power supply . 40
Figure B.1 – DC current and voltage ripple on single-phase GCPC . 41
Figure B.2 – DC current and voltage ripple on three-phase GCPC with UVRT test . 42
Figure B.3 – DC ripple I-V swing on I-V curve of PV array . 43
Figure C.1 – DC input voltage/current transition on zero-voltage ride through test – AC
voltage sudden reduction . 45
Figure C.2 – DC input voltage/current transition on zero-voltage ride through test – AC

voltage sudden recovery . 46
Figure C.3 – DC input voltage/current transition on UVRT test – AC voltage sudden
decrease . 46
Figure D.1 – DC input voltage/current transition area in the morning and evening . 47
Figure D.2 – DC input voltage transition pattern example in the morning . 48
Figure E.1 – DC input voltage/current quick transition and MPPT . 50
Figure E.2 – Irradiance quick change example . 50
Figure E.3 – Irradiation change rate for PV array and wind orientation . 51

Table 1 – Grid qualification/Requalification – In-range AC voltage before
connection/reconnection . 17
Table 2 – Grid qualification/Requalification – In-range AC frequency before

connection/reconnection . 18
Table 3 – Power capability: Nameplate P, Q, S under normal and near-normal grid
conditions . 19
Table 4 – Power capability: Limitation of P/Q/S/PF by setpoint . 20
Table 5 – Power capability: Ramp rate or soft start time-developing magnitude by set rate . 21

– 4 – IEC TS 63106-2:2022 © IEC 2022
Table 6 – Grid protection tests – AC over-voltage (OV) and under-voltage (UV) trip tests . 22
Table 7 – Grid protection tests: OF/UF trips . 22
Table 8 – Grid protection tests: Anti-islanding . 23
Table 9 – Grid protection tests: Rate of Change of Frequency (ROCOF) trips . 24
Table 10 – Grid protection tests: Open phase . 24
Table 11 – Power quality tests: Current harmonics, inter-harmonics, THDi . 25
Table 12 – Power quality tests: Flicker (continuous) . 26
Table 13 – Power quality tests: Current inrush (at connection switch close) . 27
Table 14 – Power quality tests: AC output current imbalance . 27
Table 15 – Power quality tests: Transi
...