Method for module Rsh determination and its comparison with standard methods

• Comparison between standard methods for module shunt resistance characterization.
• A new method for module Rsh characterization is proposed and tested.
• 2 Modules were manufactured for this study. One of high Rsh and other with low Rsh.
• The performance of the modules at different irradiance has been carried out.
• Several simulations on PVsyst have been carried out using the data obtained.

A method to characterize the module shunt resistance (Rsh) by measuring the module at reverse bias and dark conditions connected to an external parallel resistance is presented. For the purpose of proving this method, two modules, MA and MB, with the same type of cells, but different shunt resistance, were manufactured. The Rsh values as determined by the proposed method have been compared with those obtained by commercial flash solar simulators and other standard procedures. Additionally, modules MA and MB were measured at different irradiance levels to relate the Rsh with the module performance at low irradiance conditions. Finally, in order to evaluate the relative importance of a correct determination of the module Rsh, a simulation of Annual Energy Yield obtained with an installation made with modules MA compared with modules MB have been carried out by means of PVsyst program.