Photovoltaic Module Structure Under the High DC Voltage Stress

Today photovoltaic (PV) power sources are often photovoltaic systems of high power and so the string DC voltage can increase to hundreds of volts. Such a high voltage stresses the PV module structure including solar cells, encapsulants, supporting and protecting layers. Attention in our study is focused on changes in the electrical parameters of PV cells and modules due to thermal and potential degradation. Tests were performed on the PV mini-modules. The test modules were subjected to a controlled heat treatment and a 1000 V DC voltage stress, which is often accompanied by potentially induced degradation (PID), in the thermal chamber. Measurement of the electrical parameters of the measured samples was performed before the stress and after possible degradation process.