PV Modules

Several solar modules are connected in series/parallel to increase the voltage/current ratings. When modules are connected in series, it is desirable to have each module’s maximum power production occur at the same current. When modules are connected in parallel, it is desirable to have each module’s maximum power production occur at the same voltage. Thus, while interconnecting the modules; the installer should have this information available for each module. Solar panel is a group of several modules connected in series-parallel combination in a frame that can be mounted on a structure. Fig. 1.12 shows the construction of module and panel.

Fig. 1.13 shows a series-parallel connection of modules in a panel. In parallel connection, blocking diodes are connected in series with each series string of modules, so that if any string should fail, the power output of the remaining series strings will not be absorbed by the failed string. Also bypass diodes are installed across each module, so that if one module should fail, the output of the remaining modules in a string will bypass the failed module. Some modern PV modules come with such internally embedded bypass diodes.

Fig. 1.12: Cell, Module and Panel

Fig. 1.13: A Typical Panel: Series-Parallel Connection of Modules