Photovoltaic (PV) modules are the core of every PV system, representing the power generation
and their operation will affect the overall plant performance. It is one of the elements within a
PV site with the higher failure appearance, being essential their proper operation to produce
reliable, efficient and safety energy. Quantitative analysis and characterization of
manufacturing, soldering and breaking PV defects is performed by a combination of
electroluminescence (EL), infrared thermography (IRT), electrical current voltage (I-V) curves
and visual inspection. Equivalent-circuit model characterization and microscope inspection are
also performed as additional techniques when they contribute to the defects characterization.
A 60-cells polycrystalline module has been ad hoc manufactured for this research, with different
defective and non-defective cells. All cells are accessible from the backside of the module and
the module includes similar kinds of defects in the same bypass string. This paper characterizes
different defects of PV modules to control, mitigate or eliminate their influence and being able
to do a quality assessment of a whole PV module, relating the individual cells performance with
the combination of defective and non-defective cells within the module strings, with the
objective of determining their interaction and mismatch effects, apart from their discrete
performance.
