Testing of photovoltaic system performance Prepared by: Dr. Ali H. A. Al-Waeli Postdoctoral researcher Solar Energy Research Institute (SERI) National University of Malaysia (UKM) Some of the figures/tables in this presentation are not owned by the Presenter, they are material copyrighted to their rightful owners. This presentation is intended for non-profit educational purposes. Slides with copyrighted material (images/tables) contain the letter C in the bottom left corner. The actual presentation contains elements that are not mentioned in the PowerPoint and even edits to the PowerPoint. Only a portion of the PowerPoint is provided. Still, this presentation contain useful information and figures with regards to performance measurements of photovoltaic modules. This presentation was prepared independently by the presenter and is owned by: Dr. Ali H. A. Alwaeli

1. Testing of
photovoltaic system
performance
P R E PAR E D B Y:
D R . AL I H . A. AL - WAE L I
P O S T D O C TO R AL R E S E AR C H E R
S O L AR E N E R G Y R E S E AR C H I N S T I T U T E ( S E R I )
N AT I O N AL U N I V E R S I T Y O F M AL AY S I A ( U K M )

2. Contents
 Electrical measurements of Voc, Isc, Vmp, Imp
 Calculation of Pmp and Electrical efficiency
 Expected IV and PV curves
 Approach to monitor IV-curves
 Sizing the system

3. Multimeter
1. (-ve) terminal is the black lead
and labeled COM.
2. Plug the red lead into the V
terminal for measuring voltage
and the 10 A for large currents.
C
[1]
3

4. Multimeter
1. For voltage, set the voltage at
200 Vdc, if unsure.
2. For current, change the power
(red) lead to the 10 A socket to
prevent blowing the fuse inside
the multimeter when taking
your measurements.
C
[2]
4

5. C
[3]
[4]
5

6. Calculation of Pmpp and Electrical efficiency
C
6

7. G, irradiance (W/m2)
C
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8. G, Irradiance to be measured
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9. APV, Area receiving the irradiance (m2)
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10. Expected IV and PV curves
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11. C
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[12]
[13] 11

12. TCell, Solar cell temperature
C
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12

13. TCell on Isc and Voc, Solar cell temperature impact on open-circuit voltage and short-
circuit current
C
[15]
13

14. Approach
I. To buy an IV-curve tracing device.
II. To build an IV-curve tracing device.
III. Manual tracing using variable resistor & sensors.
Measurement
Calculation
I. IV-curve measurement using Temperature Method
14

15. IV-curve measurement using
Temperature Method
𝑽 𝒎𝒑𝒑 𝑻 = 𝑽 𝒎𝒑𝒑 𝑻 𝒓𝒆𝒇 + 𝒖𝑽 𝒎𝒑𝒑(𝑻 − 𝑻 𝒓𝒆𝒇)
𝑽 𝒎𝒑𝒑 = Maximum power point voltage at a given temperature
𝑻 𝒓𝒆𝒇 = Reference temperature
𝑻 = The measured temperature
𝒖𝑽 𝒎𝒑𝒑 = Temperature coefficient of Vmpp (datasheet)
[16]
15

16. • Advantages
• Simplicity: This algorithm solves one linear equation. Therefore, it
does not consume much computational power.
• Can be implemented as analog or digital circuits.
• Since temperature varies slowly with time, there are no steady-state
oscillation and instability.
• Low cost: temperature sensors are usually very cheap.
• Robust against noise.
• Disadvantages
• Estimation error might not be negligible for low irradiation levels (e.g.
below 200 W/m²).
IV-curve measurement using
Temperature Method
[16]
16

17. IV-curve tracing route
Method Cost Dependability Calibration Testing
Intervals
Accuracy Term Labor
Buying an
IV-curve
tracing
device
High
(estimated
at 10.5K-
25.5K
MYR)
High Easy Medium and
long
-
Easy
switching
Very high Long-term Very low
Building an
IV-curve
tracer
Medium
(estimated
to range at
5K-15K
MYR)
Medium Hard Short and
medium
-
Simultaneous
testing
Medium Short-term Medium and
Low
Manual
testing using
variable
resistor and
sensors
Cheap
(estimated
range 4-8
MYR)
Medium Easy Medium and
long
- Hard to
switch
High Short-term Very High
17

18. Buying an IV-curve tracing device
1. Solmetric | PV Analyzer I-V Curve Tracers
2. HT Instruments | HT instruments I-V 400W
multifunction instrument I-V curve tracer
3. Seaward | PV200 solar curve tracer I-V curve
tracer
18

19. 1. Solmetric
• PV Analyzer I-V Curve Tracers (Solmetric).
• Models: PVA-600+ Refurbished / PVA-1000S PV Analyzer Kit
• Website:
http://www.solmetric.com/pvanalyzermatrix.html
Requirements:
• Costs: 16,604.38 - 24,277.78 Malaysian Ringgit.
• Learn the software (easy interface).
• Learn through the provided training videos.
[17]
19

20. 1. Solmetric
C
[17]
20

21. 2. HT Instruments
• HT instruments I-V curve tracer
• Model: HT instruments I-V 400W multifunction instrument I-V curve
tracer
• Website:
https://www.ht-instruments.com/en/products/photovoltaic-testers/i-v-
curve-tracers/i-v400w/
Requirements:
• Costs: 23,425.18 Malaysian Ringgit.
• Learn the software (easy interface).
• Learn through the provided training videos.
[18]
21

22. 2. HT Instruments
C
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22

23. 2. HT Instruments
C
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23

24. 3. Seaward
• Seaward Solar Curve Tracers
• Model: PV200 solar curve tracer I-V curve tracer
• Website:
https://www.seaward.com/gb/products/solar/solar-pv-testers/389a915-
pv200-complete-kit/
https://www.tequipment.net/Seaward/PV200/Solar-Curve-Tracers/?v=0
Requirements:
• Costs: 10,514.29 Malaysian Ringgit.
• Learn the software (easy interface).
• Learn through the provided training videos.
[19]
24

25. 3. Seaward
C
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25

26. Building an IV-curve tracer
1. Proposed solutions
2. Comparison
3. Recommendation
26

27. Proposed solutions
 Resistive load (variable resistance) and sensors (manual)
 MOSFET transistors (electronic load) with oscilloscope
 MOSFET transistors with Arduino
 MOSFET transistors with FPGA
 MOSFET transistors with Phidget Vint Hub
 DC-DC converter with emulated resistor & duty cycle sweep
 PWM Charge Controller
 MPPT Charge Controller with batteries or load
27

28. Comparison criteria
• Scientific & Engineering validity
• Costs
• Complexity
• Labor
• Direct display
• Safety
• Long-term use
• Precision
28

29. METHOD COMPLEXITY PRICE LABOUR DIRECT DISPLAY
RESISTIVE LOAD LOW LOW VERY HIGH MUST BE ADDED
RESISTIVE LOAD
BATTERY (NON-
IDEAL)
LOW MEDIUM HIGH MUST BE ADDED
ELECTRONIC LOAD &
OSCILLISCOPE
HIGH HIGH HIGH YES
MOSFET TRANSISTOR
& ARDUINO
MEDIUM HIGH-MEDIUM MEDIUM-LOW YES
MOSFET TRANSISTOR
& FPGA CONTROLLER
HIGH HIGH MEDIUM-LOW YES
DC-DC CONVERTER HIGH HIGH MEDIUM-LOW YES
PWM Charge
Controller
LOW MEDIUM MEDIUM-LOW NO
MPPT and shunt
resistors
LOW HIGH-MEDIUM MEDIUM NO
29

30. Resistive load (variable resistor)
PVT1
PVT2
PVT3
PVT4
PVref Ω
Ω
Ω
Ω
PVT1
PVT2
PVT3
PVT4
PVref ΩS
S
S
S
S
PVT1
PVT2
PVT3
PVT4
PVref ΩS
S
S
S
S
Ω
(a) (b) (c) 30

31. 1 Ohm (1000W)
231.66 MYR
500 mOhm (500W)
177.48 MYR
0.01~ 10K ohm (400W)
20.46 MYR
1o Ohm (300W)
162.84 MYR (4 =
651.4 MYR)
1o Ohm (300W)
220.14 MYR (4 =
882.96 MYR)
C
31

32. ELECTRONIC LOAD
GW Instek SPS-
3610 Bench PSU
(adjustable
voltage) 0 - 36 V
DC 0 - 10 A 360
W Remote No. of
outputs 1 x
2,549.00 MYR
RS PRO Electronic DC
Load 0 → 30 A 230 V
300 W, 0.05 → 7.5 kΩ
Programmable
1,956.27 MYR
6,705.55 MYR
500V, 15A, 300W
Programmable DC
Electron
//
C
[20]
[21] [22]
32

33. MOSFET ARDUINO 1
MOSFET ARDUINO
Arduino
PVT1
PVref
MOSFET
1
MOSFET
2
Current
sensor
Voltage
sensor
DLS
PV
Current
sensor
MOSFET
1
MOSFET
2
Arduino
Voltage
sensor
1975 MYR for one device
5976.81 MYR for four devices 33

34. MOSFET FPGA (not preferred)
Example of FPGA use for PV
C
[23]
34

35. PHIDGET HUB (not preferred)
Arduino
PVT1
PVref
MOSFET
1
MOSFET
2
Current
sensor
Voltage
sensor
DLS
PV
20-bit
Current
sensor
MOSFET
1
MOSFET
2
Phidget
20-bit
Voltage
sensor
2800 MYR for one device
6000 MYR for four devices
35

36. DC-DC CONVERTER
(1) PV module that converts solar
energy to electric one.
(2) DC–DC converter that converts
produced DC voltage by the PV
module to a load voltage demand.
(3) Digital controller that drives the
converter operation with MPPT
capability.
(1) DC-DC converter with (2) duty
cycle sweep, (3) Ri is the
emulated resistor on the
terminals of the module.
(2) DC-DC is buck-boost converter.
(3) SEPIC (Single-Ended Primary
Inductance Converter) and Cuk
structures
C
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[25]
36

37. 32.50 MYR
30A PWM Solar Controller
Automatic Identification Solar
Panel Battery Dua lUSB Charge
pelita lampu
Charge Controller
Solar Technology STCC20 20A Dual
Battery Solar Charge Controller
326.10 MYRC
[26] [27]
37

38. • Solar Charge Controller MPPT 20A 12V/24V
359.00 MYR
MPPT Charge Controller
C
[28]
38

39. • FJS LCD Display High Power MPPT Controller MPPT Focus Tracking
Intelligent Wide Voltage Auto Recognition MPPT Solar Charging
DUMUDA 12V/24V/48V 10-40A Current Regulation
• 224.9 MYR
MPPT Charge Controller
C
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39

40. • Morningstar SunSaver MPPT Charge Controller | World Leading
Solar Controllers & Inverters
1297 MYR
MPPT Charge Controller
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40

41. • MPPT Solar Charge Controller
12V/24V Intelligent Regulator
Module Display Standard 2+USB
COM Slave, MPPT Solar Controller,
Solar Charge Controller, Intel
MPPT Charge Controller
630.70 MYR
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42. MORNINGSTAR SUNSAVER SS-MPPT-
15L CHARGE CONTROLLER
•Morningstar’s SunSaver MPPT solar controller with
TrakStar Technology™ is an advanced maximum power
point tracking (MPPT) battery charger for off-grid solar
systems. The controller features a smart tracking
algorithm that maximizes the energy harvest from the PV
and also provides load control to prevent over discharge
of the battery. The SunSaver MPPT is well suited for both
professional and consumer solar applications. Its charging
process has been optimized for long battery life and
improved system performance. This product is epoxy
encapsulated for environmental protection, may be
adjusted by the user via four settings switches or
connection to a personal computer, and has an optional
remote meter and battery temperature sensor.
1,060.86 MYR
C
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42

43. Victron SmartSolar MPPT 75/10 Solar Charge
Controller 75V 10A with Bluetooth (4 pieces with
shipment = MYR 2,139.65)
C
[32]
43

44. Victron SmartSolar MPPT 100/20 Solar Charge
Controller 100V 20A with Bluetooth
(3 pieces with shipment = MYR MYR 2,583.31)
C
[32]
44

45. My Recommendation for experiments
• To carryout two stages of testing.
1. The first stage focuses on (i) Voc and Isc along with estimation
of the Vmp, (ii) variable load resistor tracing.
2. The second stage focuses on using either a bought or
manufactured tracing system. If the costs are similar, then buying
the tracing system is recommended.
45

46. My recommendation for safety
considerations
• In-line fuses.
• Reverse current protection.
• Overload protection.
• Open circuit protection.
• Lightning surge protection.
• Charge current protection up to 10A (RS 905-4532).
46

47. Perhaps the following:
• Purchase two variable resistors. Begin the measurements. In
the meantime work on the switching mechanism. Then, start
purchasing the IV-curve tracing system or setup low-cost MPPT
controllers with batteries.
47

48. Sizing the system
48

49. Textbook in PV/TPhotovoltaic/Thermal (PV/T) Systems: Principles,
Design, and Applications
49

50. References
[13] Thermosiphon Water Heater. Apricus solar hot water. Link: http://www.apricus.com/thermosiphon-water-heater-30/ (Retrieved on 29th of October
2019).
[14] Flat Plate Solar Collectors. Apricus solar hot water. Link: http://www.apricus.com/flat-plate-solar-collectors-3/ (Retrieved on 29th of October 2019).
[15] Solar Thermosiphon. RHEEM. Link: https://www.rheem-mea.com/products/water-heating/solar/solar-thermosiphon/ (Retrieved on 29th of October
2019).
[16] Active Solar Heating Systems. E-EDUCATION. Link: https://www.e-education.psu.edu/egee102/node/2097 (Retrieved on 29th of October 2019).
[17] Solar Hot Water Heater. Exporters India. Link: https://www.exportersindia.com/illusions4real/solar-hot-water-heater-3465688.htm (Retrieved on 27th
of October 2019).
[18] Solar Water Heater - Flat Plate Collector Type. IndiaMArt. Link: https://www.indiamart.com/proddetail/solar-water-heater-flat-plate-collector-type-
11569064591.html (Retrieved on 29th of October 2019).
[19] The Rheem Solar Thermosyphon water heater line is engineered for longer life with quality storage tank casing. Link: https://rmc-
cdn.s3.amazonaws.com/site/rheemmea/documents/wh/Data%20Sheets/1%20-%20Solar%20Thermosiphon.pdf (Retrieved on 29th of October 2019).
[20] Carmella Daniel. History, Design, and Applications Solar Hot Water Systems Ben Gravely - Holocene Technologies Blog A (very) Brief. Link:
https://slideplayer.com/slide/7116432/ (Retrieved on 31st of October 2019).
[21] Kabo Leshoai. Materials used to make solar panels. Dsolar. Link: https://dsolar.co.za/materials-used-to-make-solar-panels/ (Retrieved on 1st of
November 2019).
[22] Effect of Temperature. Pveducation. Link: https://www.pveducation.org/pvcdrom/solar-cell-operation/effect-of-temperature (Retrieved on 1st of
November 2019).
[23] Our Approach. Link: http://web.mit.edu/3.042/team5_10/OurApproach.html (Retrieved on 29th of October 2019).
[24] B. Lee, J. Z. Liu, B. Sun, C. Y. Shen, G. C. Dai "Thermally conductive and electrically insulating EVA composite encapsulants for solar photovoltaic
(PV) cell" eXPRESS Polymer Letters Vol.2, No.5 (2008) 357–363.
50

51. Follow me on social media
www.linkedin.com/in/ali-al-waeli-a76a33124
https://www.researchgate.net/profile/Ali_Al-Waeli
https://www.facebook.com/AliHWaeliAR/
https://www.facebook.com/AliHwaeli/
Website: https://www.dralialwaeli.org/
51

52. Disclaimer
Some of the figures/tables in this presentation are not owned by the
Presenter, they are material copyrighted to their rightful owners. This presentation is
intended for non-profit educational purposes.
Slides with copyrighted material (images/tables) contain the letter C in the bottom
left corner.
The actual presentation contains elements that are not mentioned in the PowerPoint
and even edits to the PowerPoint. Only a portion of the PowerPoint is provided.
Still, this presentation contain useful information and figures with regards to
performance measurements of photovoltaic modules.
This presentation was prepared independently by the presenter and is owned by:
Dr. Ali H. A. Alwaeli
52

53. References
[1] How to Use a Multimeter. Science buddies. Link: https://www.sciencebuddies.org/science-fair-projects/references/how-to-use-a-multimeter#multimetergallery
(Retrieved: 28th of October 2019).
[2] Module Measurement without Load. Pveducation.org. Link: https://www.pveducation.org/pvcdrom/modules-and-arrays/module-measurement-without-load
(Retrieved: 28th of October 2019).
[3] Link: http://8.laiser.co/how-to-measure-current-and-voltage-in-a-circuit.html (Retrieved on 28th of October 2019)
[4] Module Measurement with Load. Pveducation.org. Link: https://www.pveducation.org/pvcdrom/modules-and-arrays/module-measurement-with-load
(Retrieved on 28th of October 2019).
[5] Apogee instruments. Monitoring PV Panels on Jin Jeop Library. Link: https://www.apogeeinstruments.com/monitoring-pv-panels-on-jin-jeop-library/ (Retrieved
on 10th of August 2020).
[6] Dissecting the Differences Between Pyranometer and Reference Cell Irradiance Measurements. Slideshare. Link:
https://www.slideshare.net/sandiaecis/dissecting-the-differences-between-pyranometer-and-reference-cell-irradiance-measurements (Retrieved on 10th of August
2020).
[7] Average Solar Radiation. PVEducation. https://www.pveducation.org/pvcdrom/properties-of-sunlight/average-solar-radiation (Retrieved on 10th of August
2020).
53

54. References
[8] Ooshaksaraei, P., Sopian, K., Zulkifli, R., Alghoul, M. A., & Zaidi, S. H. (2013). Characterization of a bifacial photovoltaic panel integrated with external diffuse
and semimirror type reflectors. International Journal of Photoenergy, 2013.
[9] Power Systems Design –II. Tate Upshaw. Slideshare: https://slideplayer.com/slide/1719012/ (Retrieved on 10th of August 2020).
[10] Solar Photovoltaic. HKRENet. Link: https://re.emsd.gov.hk/english/solar/solar_ph/Electrical_Properties_of_PV_Modules.html (Retrieved on 10th of August
2020).
[11] How does temperature and irradiance affect I-V curves? Seaward. https://www.seaward.com/gb/support/solar/faqs/00797-how-does-temperature-and-
irradiance-affect-i-v-curves/ (Retrieved on 10th of August 2020).
[12] Effect of temperature. PVEducation. Link: https://www.pveducation.org/pvcdrom/solar-cell-operation/effect-of-temperature (Retrieved on 10th of August
2020).
[13] Ibrahim, O., Yahaya, N. Z., Saad, N., & Umar, M. W. (2015, October). Matlab/Simulink model of solar PV array with perturb and observe MPPT for
maximising PV array efficiency. In 2015 IEEE Conference on Energy Conversion (CENCON) (pp. 254-258). IEEE.
[14] How to Test a Solar Panel. Low Energy Development. Link: https://www.lowenergydevelopments.com.au/how-to-test-a-solar-panel (Retrieved on 10th of
August 2020).
[15] El Amin, A. A., & Al-Maghrabi, M. A. (2018). The analysis of temperature effect for mc-Si photovoltaic cells performance. Silicon, 10(4), 1551-1555.
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55. References
[16] Coelho, R. F., Concer, F. M., & Martins, D. C. (2010, December). A MPPT approach based on temperature measurements applied in PV systems. In 2010 IEEE
International Conference on Sustainable Energy Technologies (ICSET) (pp. 1-6). IEEE.
[17] PV Analyzer I-V Curve Tracers. Solmetric. Link: http://www.solmetric.com/pvanalyzermatrix.html (Retrieved on 10th of August 2020).
[18] I-V400w. HT Instruments. Link: https://www.ht-instruments.com/en/products/photovoltaic-testers/i-v-curve-tracers/i-v400w/ (Retrieved on 10th of August 2020).
[19] PV200 Complete Kit. Seaward. Link: https://www.seaward.com/gb/products/solar/solar-pv-testers/389a915-pv200-complete-kit/ (Retrieved on 10th of August 2020).
[20] GW Instek SPS-3610 Bench PSU (adjustable voltage) 0 - 36 V DC 0 - 10 A 360 W Remote No. of outputs 1 x. Link: https://www.fruugo.my/search/?q=GW+Instek+SPS-
3610+Bench+PSU+%28adjustable+voltage%29+0+-+36+V+DC+0+-+10+A+360+W+Remote+No.+of+outputs+1+x (Retrieved on 10th of August 2020).
[21] RS PRO Electronic DC Load 0 → 30 A 230 V 300 W, 0.05 → 7.5 kΩ Programmable. Link: https://my.rs-online.com/web/c/test-measurement/bench-power-and-power-
measurement/electronic-loads/ (Retrieved on 10th of August 2020).
[22] BK Precision 8502B - 500V, 15A, 300W Programmable DC Electronic Load. Tequipment. Link: https://www.tequipment.net/BK/8502B/Electronic-Loads/ (Retrieved on 10th
of August 2020).
[23] Gad, H. H., Haikal, A. Y., & Ali, H. A. (2017). New design of the PV panel control system using FPGA-based MPSoC. Solar Energy, 146, 243-256.
[24] Othman, A. M., El-arini, M. M., Ghitas, A., & Fathy, A. (2012). Realworld maximum power point tracking simulation of PV system based on Fuzzy Logic control. NRIAG
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56. References
[25] Duran, E., Piliougine, M., Sidrach-de-Cardona, M., Galan, J., & Andujar, J. M. (2008, May). Different methods to obtain the I–V curve of PV modules: A
review. In 2008 33rd IEEE Photovoltaic Specialists Conference (pp. 1-6). IEEE.
[26] Lazada. https://www.lazada.com.my/shop-solar-and-wind-power/?spm=a2o4k.pdp.breadcrumb.4.5ee3751deaGHlk (Retrieved on 10th of August 2020).
[27] RS Online. Link: https://my.rs-online.com/web/p/products/9054536/ (Retrieved on 10th of August 2020).
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[30] Ubuy. Link: https://www.ubuy.com.my/en/catalog/product/view/id/11013892/s/morningstar-corporation-ss-mppt-15l-energy-solar-charge-
controllers?gclid=CjwKCAjw9vn4BRBaEiwAh0muDL6Ci3YUlDPBAMd1pcVwlz4Isog_9s3u-u3Jqi09IoE5_NBVOzcD_hoChAsQAvD_BwE (Retrieved on 10th of
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56

57. Thank you