Introduction:
Bypass diodes are used in series connected solar panels to protect shaded cells. When a solar panel is partially shaded, the shaded cells receive less sunlight compared to the rest of the cells. This leads to a mismatch in the current produced by the shaded cells, which can significantly reduce the overall efficiency of the solar panel. Bypass diodes are employed to mitigate the negative effects of shading and ensure the optimal performance of the solar panel.

Explanation:
When a solar panel is connected in series, the current flowing through each cell is the same. However, if a cell is shaded, its current production is reduced, which can result in a significant drop in the overall current generated by the panel. This is due to the fact that the shaded cell acts as a load, drawing current from the other cells. As a result, the power output of the entire panel is decreased.

Function of Bypass Diodes:
The purpose of using bypass diodes in series connected solar panels is to provide an alternative pathway for the current to flow when a cell is shaded. The bypass diodes are connected in parallel with each cell or a group of cells. When a cell is shaded, the bypass diode provides a low resistance path for the current to bypass the shaded cell. This prevents the shaded cell from reducing the overall current of the panel.

Protection of Shaded Cells:
By using bypass diodes, the shaded cells are protected from the reverse bias voltage that can occur when the current produced by the shaded cells is lower than the current produced by the unshaded cells. Without bypass diodes, the shaded cells would experience an excessive reverse voltage, which could damage the cells and reduce their lifespan.

Improved Efficiency:
The use of bypass diodes in series connected solar panels allows the unshaded cells to continue producing maximum power even when some cells are shaded. This improves the overall efficiency of the solar panel system. The bypass diodes ensure that the shaded cells do not act as a load and drag down the performance of the entire panel.

Conclusion:
In summary, the purpose of using bypass diodes in series connected solar panels is to protect shaded cells and prevent them from reducing the overall current output of the panel. The bypass diodes provide an alternative pathway for the current when a cell is shaded, ensuring that the unshaded cells can continue producing maximum power. This improves the efficiency and lifespan of the solar panel system.