Fuzzy Fractional order PI Controller for a Multilevel Inverter for Grid-Connected Photovoltaic Systems (PV)

These Applications of fractional calculus are becoming more and more effective, adaptable, and have produced positive outcomes in a variety of engineering and scientific domains. In this paper, a fuzzy fractional-order PI-based control approach for grid-connected photovoltaic (PV) systems is presented. The various advantages of multi-level inverters (MLIs) in industrial and grid-connected applications have resulted to their increasing application in recent years. A five-level neutral point (NPC) inverter is used to integrate PV electricity into the electrical grid with minimal harmonic distortions and highest power capacity. The output voltage of the inverter must be maintained in order to connect to a grid, even though that the photovoltaic output voltage varies considerably with solar radiation. To achieve this, three fuzzy fractional order PI (FFOPI)controllers were used to control the inverter output voltage (Vdc), direct current (Id), and quadratic current (Iq) around a reference values. A further comparison is made with the fuzzy PI (FPI). According to research, the FFOPI controller outperforms the FPI controller in terms of performance.