Design of digital battery charger system based on PV-module

This paper aims at to realize the solar cell charged systems of 120W PV module with the dsPIC30F4011 control chip. All of the control schemes are written and accomplished with the C language. In the power converter, a single-ended primary inductance converter (SEPIC) is adopted which has the features including the buck-boost operating mode, no polarity inversion, low input current pulsation, and wide input voltage range, so, it is very suitable for the conversion of solar cell. In order to obtain the high efficient solar cell energy conversion, a fuzzy maximum power point tracking (MPPT) control is activated if the solarization is insufficient. The fuzzy controller is to maintain a charged current so as that the battery voltage can reach to desired value. The effectiveness of the proposed methods is demonstrated with the experimental results.