A PI and Fuzzy Controller Based High Gain DC-DC Converter for Solar PV Grid Applications

Abstract

The solar energy is considered as one of the important renewable energy as it generates no harmful gases and contributes majorly in electricity generation.  The DC output voltage obtained from solar cannot be directly used in applications due to its fluctuating nature. Several DC-DC converters suitable for solar Photo Voltaic (PV) have been discussed in the literature. In this work, a non-isolated SEPIC converter that provides high gain is used for solar PV applications. A constant voltage of 380 Vdc is derived from solar PV with the help of this converter by suitably modifying the gating pulses applied to the switches. The converter configuration finds an application in renewable DC Microgrids. The converter is designed and simulated for a load power of 500 W. A Proportional Integral (PI) and Fuzzy Logic Controller (FLC) are employed to verify the performance of the converter under varying load conditions and different solar irradiations.

Keywords: DC Microgrid, solar PV, Modified SEPIC converter, PI controller, Fuzzy Logic Controller.