Higher PV Module Efficiency by a Novel CBS Bypass

Abstract

There is an increasing focus on reducing costs and improving efficiency for photovoltaic (PV) cells and modules as well as finding a more efficient approach to the product manufacturing. This letter introduces an innovative solution to bypass shaded PV cells instead of a traditional Schottky diode, in order to avoid overheating of cells in the case of partial shading. The goal is to reduce the power dissipation and improve the general efficiency of a PV generator. A novel device called cool bypass switch is then presented. It is made up of a Power MOS driven by a controller with the task to charge a storage capacitor. Tests and comparisons with standard Schottky diodes are then performed and experimental results are reported in terms of current intensity and operating temperature. The resulting circuit shows better diode performances and considerably lower dissipated power in shading condition. The little packing cases allow an easy integration inside the PV module. In comparison with traditional diodes, the integrated power switch provides a negligible leakage current during PV panel energy production.