Baseline Testing Procedures For Pv Modules Beyond The Qualification Testing

The qualification tests described in IEC 61215 for the c-Si PV modules are essentially pass/fail tests that assist in avoiding infant mortality. This paper reports on the baseline test procedure carried out on PV modules at Florida Solar Energy Center that go beyond the pass/fail criteria of the qualification tests and obtain information about the degradation modes and mechanisms. The importance and limitations of the various characterization techniques are described. Electroluminescence imaging has been used to detect and categorize the faults at the cell level. Indoor infrared imaging has been used to study the quality of electrical interconnects in the module. The infrared imaging carried out on the modules while they are undergoing outdoor exposure has provided information about the presence and distribution of hot spots in these modules. Conventionally, the insulation resistance tester has been used mostly for the dry and wet leakage test. In this study, the importance of the polarization index test and voltage excursion test are described. The use of these tests is essential to provide insight into the modes and mechanisms of degradation, during reliability and durability studies of PV modules. A predictive model for the service life of a PV module may be developed through the results obtained from these characterization techniques in conjunction with long-term exposure and accelerated lifetime tests. © 2013 SPIE