Comparative Study on Battery Charging Using Self-Regulating Solar PV Modules of Different Specifications

Abstract— This paper compares performance parameters of three self-regulating photovoltaic modules tested outdoors simultaneously without charge controller. The open circuit voltages ( V_oc) of these three modules were 21.1 Volts (standard specifications available in the market), 19.2 and 17.4 Volts (custom fabricated). Data presented for each module includes I-V and P-V curves of the panels obtained at actual operating conditions and also the charging rates as obtained by these panels. The battery charging voltage (i.e. 14.2 volts), as recommended by the manufacturers, is exceeded by all the three panels but for a short period and thus does not damage the battery. The Vmax of any PV module is dependent on the distance of the PV module from the battery. Index Terms— Battery charging, Charge controller; conversion efficiency, Charging voltage, Solar PV module, Self-regulating PV modules,