Fault diagnosis of visual faults in photovoltaic modules: A Review

ABSTRACT

Energy demand in the world is overgrowing due to rising population and technological developments. It is vital to move toward a reliable, economical, and sustainable renewable energy source for energy needs arising in the future. Among other renewable energy sources, solar energy is a promising source of energy for handling long-term problems in the energy crisis. Solar power generation is expanding globally due to high energy demands and decreasing fossil fuel reserves, which are currently the primary sources of power generation. Photovoltaic (PV) cells are employed in the field of solar power generation for the conversion of solar radiation into electricity. Multiple PV cells combine in series or parallel to form a PV module (PVM). They are operated under continually changing environmental conditions causing various faults. Typically, faults are classified into visual, electrical, and miscellaneous faults. These faults should be identified and corrected immediately so that the performance, lifetime, and reliability of PV modules remain unaffected. This paper focuses on the detailed study of the types and causes of various faults that occur in a PVM. Several methods discussed in literature for fault diagnosis of PVM are reviewed. Faults occurring in PVM are particularly highlighted and diagnosis methods to detect and classify faults accurately are elaborated. Recommendations for future research direction are provided based on the reviewed papers.

KEYWORDS:

• Fault diagnosis
• visual faults
• photovoltaic cell
• photovoltaic modules
• renewable energy

Nomenclature

PV	=	Photovoltaic
PVM	=	Photovoltaic Module
EVA	=	Ethylene Vinyl Acetate
UV	=	Ultraviolet
DC	=	Direct Current
c-Si	=	Monocrystalline
x-Si	=	Polycrystalline
a-Si	=	Amorphous
CdTe	=	Cadmium Telluride
CIS	=	Copper Selenium Indium
CIGS	=	Copper Indium Gallium Selenium
IEC	=	International electrotechnical commission
UAV	=	Unmanned Aerial Vehicle
IRT	=	Infrared thermography
EL	=	Electroluminescence
PL	=	Photoluminescence
ELI	=	Electroluminescence Imaging
CCD	=	Charge Coupled Device
PLI	=	Photoluminescence Imaging
Pmax	=	Maximum Output Power
Vmp	=	Maximum Voltage
Isc	=	Maximum Current
FF	=	Fill Factor
CFSSM	=	Code Based Fast Fault Simulation Model
DE	=	Differential Evolution
AI	=	Artificial Intelligence
ANN	=	Artificial Neural Networks
FL	=	Fuzzy Logic
GA	=	Genetic Algorithms
HS	=	Hybrid Systems
TMA	=	Triangular Moving Average
SVM	=	Support Vector Machine
MLT	=	Machine Learning Techniques
DT	=	Decision Tree
kNN	=	k- Nearest Neighbor
GPS	=	Global Positioning System