A new bypass circuit for hot spot mitigation

Abstract

Overtemperature occurring in silicon solar panels subject to partial shadowing are reduced by means of a new bypass circuit. The circuit exploits a series connected power MOSFET which sustains part of the reverse voltage developing across the shaded solar cell. Neither power supply nor control logic are required, resulting in an appealing advantage with respect the other active bypass circuits. Experiments performed on a commercial mono-crystalline solar panel evidenced a reduction of the reverse voltage across a shaded cell, if compared with the traditional bypass diode, of about 50%, corresponding to a temperature decease approaching 22°C.