By: Wael Fareed-Batch 5

Transcription

1 REMENA Master Thesis Voltage and Time Dependence of The Potential Induced Degradation Effect For Different Types of Solar Modules By: Wael Fareed-Batch 5 Supervisors: Prof. Dr. Dirk Dahlhaus Prof. Dr. Iman El Mahallawi Prof. Dr. Adel Khalil Prof. Dr. Hans J. Möller Examiners Committee: Prof. Dr. Iman El Mahallawi Prof. Dr. Sayed Kaseb Dr. Hani Elnokraschy Raykov, Detection of PID, Intersolar 14 Wael Fareed REMENA batch#5

2 Outline Goal and objective of the research project Literature review Methodology Finding and results Conclusion and recommendations Wael Fareed REMENA batch#5 1

3 Goal and objective of the research The objective of the study is to investigate the potential induced degradation problem on different types of solar modules under dependency of varying time and voltage. Study Scope Conducting the performance measurements on different kinds of solar modules (mini silicon module, CdTe modules and cells silicon modules). Leakage current measurements for different module types. Characterization of the tested different module types. Taking a closer look at the PID effect by using electroluminescence image. Analyses of the experimental data to obtain the PID effect on the different module types. Wael Fareed REMENA batch#5 2

4 Outline Goal and objective of the research project Literature review Methodology Finding and results Conclusion and recommendations Wael Fareed REMENA batch#5 3

5 What is the PID? Potential Induced Degradation (PID) is an undesirable property of some solar Modules which the modules can lose more than %. Classification of the affected parameters on PID effect: Table : classification of the affected parameters on PID effect[1] Influencing system level Influencing on module level Influencing on cell level Voltage EVA encapsulation AR-Coating Temperature Front glass sheet Emitter depth Humidity Back sheet Type of base doping Grounding. Module design [1]Schüetze, et al, Laboratory Study of Potential Induced Degradation of SiliconPhotovoltaic Modules, Q-Cells Wael Fareed REMENA batch#5 4

6 PID cause levels 1-System level EL image of a panel positions with negative and positive grounding 2-Panel level [IEEE PID Paper Pingel Solon] Panel test setup for PID [IEEE PID Paper Pingel Solon] Leakage current paths Wael Fareed REMENA batch#5 5

7 Leakage currents at different polarities (+), (-) 0VDC for c-si modules against inverse absolute module temperature, in three bands of relative humidity values, %, %, and 95% J.A. del Cueto et al Degradation of Photovoltaic Modules Under High Voltage Stress in the Field Calfornia August 1-5, Wael Fareed REMENA batch#5 6

8 Outline Goal and objective of the research project Literature review Methodology Finding and results Conclusion and recommendations Wael Fareed REMENA batch#5 7

9 Tested modules types 1-Mini modules (1 cell) 2 modules-refrence glass/back sheet (M1,M2) 1 module-reference glass/reference glass (M3) 1 module-special glass/back sheet (M4) 2-standard silicon modules ( cells) 1 new mono-crystalline module (a) 1new poly-crystalline module (b) 2 stressed (poly-crystalline) modules(dht,tct) (c,d) 3-Cadmium telluride (CdTe) 2 tested outdoors CdTe modules Wael Fareed REMENA batch#5 8

10 The work test sequence Wael Fareed REMENA batch#5 9

11 Outline Goal and objective of the research project Literature review Methodology Finding and results Conclusion and recommendations Wael Fareed REMENA batch#5

12 Current (A) P (%) First mini module I-V curve Inverse of the slope gives R s Voltage(V) Inverse of the slope gives R sh 0w/m2 0w/m2 0w/m2 00w/m2 0w/m2 0w/m2 0w/m2 00w/m2 First mini module IV curves comparison in different intensities flash measurement between before PID with solid lines and after (-2kv- 139hour) PID test with dotted lines test %.96% 9.72% 4.31% First mini module PID power losses progress percentage at different flash test Wael Fareed REMENA batch#5 11 0I- p(t) 0I- p(t) 0I- p(t) 00I- p(t)

13 I (µa) Module Type P at Different I M1(Reference glass/back sheet) 139hr All mini modules power loss and leakage current Table: Comparison between the tested mini modules in power losses by using different flash tests M2(Reference glass/back sheet) 67hr M3(Glass/Glass) 1hr P(%) at 0W/m P(%) at 0W/m P(%) at 0W/m P(%) at 00W/m M4(Special glass/back sheet) 115hr ,4% % ,4% 5,5% M1 M2 M3 M4 All investigated mini modules leakage current over time of experiments with the same conditions Wael Fareed REMENA batch#5 12

14 Current (A) Mono-crystalline module Standard silicon modules results The characterizations data for the first standard module (new mono-crystalline) pre and post the high voltage test was recorded as shown in table. V oc (V) I sc (A) V m (V) FF(%) Eff. (%) P m (W) R sh ( ) R s ( ) P losses (%) Before PID After-1kv,3 h I SC IV curve for fresh mono Voltage (V) I m,v m R s =inverse the slope V OC R sh =inverse the slope before After-1kv,44hr After-1kv,66hr After-1kv,88hr After-1kv,158hr After-1kv,3hr IV characterization curve for the fresh mono crystalline before and after the PID test Wael Fareed REMENA batch#5 13

15 power loss (%) Mono-Crystalline Power Loss Electroluminescence Power loss High Current Pass P=0% Wael Fareed REMENA batch#5 14

16 power loss (%) Electroluminescence Power loss High Current Pass P=2% Wael Fareed REMENA batch#5 14

17 power loss (%) Electroluminescence Power loss High Current Pass P=11% Wael Fareed REMENA batch#5 14

18 power loss (%) Electroluminescence Power loss High Current Pass P=14% Wael Fareed REMENA batch#5 14

19 power loss (%) Electroluminescence Power loss High Current Pass P=23% Wael Fareed REMENA batch#5 14

20 power loss (%) Electroluminescence Power loss High Current Pass P=26% Wael Fareed REMENA batch#5 14

21 power loss (%) Electroluminescence Power loss High Current Pass P=34% Wael Fareed REMENA batch#5 14

22 power loss (%) Electroluminescence Power loss High Current Pass P=35% Wael Fareed REMENA batch#5 14

23 power loss (%) Electroluminescence Power loss High Current Pass P=51,5% Wael Fareed REMENA batch#5 14

24 power loss (%) Electroluminescence Power loss High Current Pass P=52% Wael Fareed REMENA batch#5 14

25 power loss (%) Electroluminescence Power loss High Current Pass P=54,9% Wael Fareed REMENA batch#5 14

26 power loss (%) Electroluminescence Power loss High Current Pass P=55,2% Wael Fareed REMENA batch#5 14

27 power loss (%) Electroluminescence Power loss High Current Pass P=57% Wael Fareed REMENA batch#5 14

28 Current (A) Poly-crystalline module The characterizations data for the second standard module (new Poly-crystalline) pre and post the high voltage test was recorded as shown in table. V oc (V) Isc(A) V m (V) FF(%) Eff.(%) P m (W) R sh ( ) R s ( ) P losses (%) Before PID After-1kv,186 h Poly IV PID Curve R s =inverse slope R sh =inverse slope Before PID After-1kv,5hr After-1kv,22hr After-1kv,45hr After-1kv,115hr After-1kv,138hr After-1kv,161hr After-1kv,186hr IV characterization curve for the fresh poly crystalline module before and after the PID test 0 0 Voltage (V) Wael Fareed REMENA batch#5 15

29 Power loss (%) Poly-Crystalline Power Loss Electroluminescence Power loss High Current Pass P=0% Wael Fareed REMENA batch#5 16

30 Power loss (%) Electroluminescence Power loss High Current Pass P=0% Wael Fareed REMENA batch#5 16

31 Power loss (%) Electroluminescence Power loss High Current Pass P=4.1% Wael Fareed REMENA batch#5 16

32 Power loss (%) Electroluminescence Power loss High Current Pass P=5% Wael Fareed REMENA batch#5 16

33 Power loss (%) Electroluminescence Power loss High Current Pass P=5.2% Wael Fareed REMENA batch#5 16

34 Power loss (%) Electroluminescence Power loss High Current Pass P=6.3% Wael Fareed REMENA batch#5 16

35 Power loss (%) Electroluminescence Power loss High Current Pass P=6.5% Wael Fareed REMENA batch#5 16

36 Power loss (%) Electroluminescence Power loss High Current Pass P=8% Wael Fareed REMENA batch#5 16

37 Power loss (%) Mono and Poly power loss comparison Electroluminescence Mono High Current Pass Poly High Current Pass Power Loss Comparison Mono power loss Poly power loss 55% 8% Wael Fareed REMENA batch#5 17

38 ARC observation Comparison between the highly degrade new mono-crystalline module (right) and the lower degrade new poly-crystalline module (left) Wael Fareed REMENA batch#5 18

39 TCT stressed module with its photography view (Right) and its EL image after (External Voltage= - 00V, T=25ºC±5, RH=45%±5 and t=89 hours) PID test Wael Fareed REMENA batch#5 19

40 I (µa) Power loss (%) 1-Time dependence test comparison All standard silicon modules comparison % % 39% 4% 8% 57% Poly power losses Mono power losses TCT power losses DHT power losses DHT leakage current Poly leakage current Mono leakage current TCT leakage current All the standards modules under Time dependence PID test comparison for voltage losses (top) and leakage current (bottom) Wael Fareed REMENA batch#5

41 I (µa) Power loss (%) 2-Voltage dependence test comparison External Voltage (kv) y = x x R² = Poly voltage dep. losses Mono voltage dep. losses TCT voltage dep. losses DHT voltage dep. losses All the standards modules under Voltage dependence PID test comparison for power losses 0 0 y =.233x R² = y =.626x R² = y = x x R² = External Voltage (kv) DHT Voltage dep. leakage TCT Voltage dep. leakage Poly Voltage dep. leakage Mono Voltage dep. leakage All the standards modules under Voltage dependence PID test comparison for and leakage current Wael Fareed REMENA batch#5 21

42 IV Curves for the first CdTe module Figure: I-V curve for M9 module before and after PID test with different external voltages (a) 0W/m 2 measure (b) 00W/m 2. Wael Fareed REMENA batch#5 22

43 Outdoor test Protect the front glass with sprayer to prevent: Dust accumulations Water adsorption CdTe non sprayed module at 45º tilt angle CdTe sprayed module at 45º tilt angle Wael Fareed REMENA batch#5 23

44 Outline Goal and objective of the research project Literature review Methodology Finding and results Conclusion and recommendations Wael Fareed REMENA batch#5 24

45 Conclusions ARC is another factor beside the leakage current which both affect on PID. The leakage current for all modules was increasing during the time dependent PID test. The pre-stressed modules showed a higher degradation during the time dependence test than the new modules. Leakage currents were observed to be constant after beginning the PID test for the accelerated situation, while in new modules it was slightly decreasing over time. No additional destruction was observed at the higher stressed voltages(2-kv). Wael Fareed REMENA batch#5 25

46 Recommendations for future work Investigate the PID on cells with the same aspects (same manufacturing process) but different AR coating thickness. Investigate any kind of materials to be sprayed on the module front glass surface which can be able to protect from PID due to increased glass conductivity by humidity. Further investigations on CdTe modules, since it completely resists the PID phenomenon during my investigations. Avoid applying bias voltage to the PV module by grounding the negative pole of the PV string array and using a transformer inverter [2](expensive solution). [2] Ivo Kastle, Dealing with high voltage stress, PV Magazin, 11 Wael Fareed REMENA batch#5 26

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