What is the primary purpose of bypass diodes in a PV module?

Bypass diodes are primarily included in photovoltaic (PV) modules to limit the effects of shading. When a section of a solar panel is shaded, the affected cells can become less productive, which can lead to overheating and potential damage to those cells. Bypass diodes act as a safety mechanism, providing an alternative path for the current to flow around the shaded or malfunctioning cells. This allows the rest of the cells in the module to continue operating normally, minimizing the overall reduction in power output that would occur if the shaded cells were bypassed without this protective measure.

This design is crucial because, without bypass diodes, a shaded solar cell can act as a resistive load, potentially leading to significant energy loss and even permanent damage. By allowing the current to bypass the affected cells, these diodes help maintain the overall performance and efficiency of the solar array under various lighting conditions.