Maximum power point tracking by the small-signal-based pi and fuzzy logic controller approaches for a two-stage switched-capacitor dc-dc power boost converter; applicable for photovoltaic utilizations

Abstract

For the Photovoltaic panels, one of the main troubles is generating the limited values of the voltage. To enhance this DC voltage for grid applications, high-voltage gain, transformer-less, low-voltage stress, and efficient DC-DC boost converters are used. The main concern is keeping the voltage constant at the output ends of the converter by changing the voltage of the PV array or the value of the load under the maximum power of the array through the simple control approaches. This approach is well-known as the Maximum Power Point Tracking (MPPT). This study presents the control process for the Two-stage Switched-Capacitor (SC) cell-based boost converter with Proportional Integral (PI) and fuzzy logic controller methods. Two-stage SC cell-based boost converter has been used instead of the conventional boost converter to provide higher voltage gain and lower voltage stresses on the power switch. In the proposed study, the voltage gain and efficiency of the boost converter are computed utilizing the method of the inductors volt-second balance and capacitor current-charge approaches. The compared systems were tested at different input voltages, and the output voltage is fixed at 200 VDC. Results exhibit the comparison between PI controller and fuzzy logic controller algorithms applied to the converter. In this article, MATLAB / SIMULINK software was utilized. The final results demonstrate that the fuzzy logic controller has quicker performance compared with PI Control but the PI controller has less overshoots and undershoots at the change time of the input voltage or output load.