Selected Harmonic Elimination for Cascaded Multilevel Inverter Based on Photovoltaic with Fuzzy Logic Control Maximum Power Point Tracking Technique

摘要

This paper describes the work performed on a single phase 9-level cascaded H-Bridge multilevel inverter (CHB-MLI) for photovoltaic (PV) power generation, using two methods of maximum power point tracking (MPPT)—namely fuzzy logic controller (FLC) and perturbation & observation (P&O). The MPPT scheme is used to extract maximum power from solar PV cells. PV cell temperature and solar irradiation are input quantities and the two used methods estimate the optimum duty cycle to ensure DC-DC boost converter maximum output. This paper also compares the results obtained by the work performed on CHB-MLI with DC-DC boost converter using FLC based MPPT controller to that of results obtained with the conventional P&O method. The fuzzy logic controller works with imprecise inputs, it does not need an accurate mathematical model and it can handle nonlinearity well. Besides, fuzzy is more robust as compared to the conventional non-linear controller. The genetic algorithm (GA) based Selective Harmonic Elimination (SHE) technique is also applied to CHB-MLI for the elimination of harmonics from the output voltage. In the work reported in this paper on PV inverter making use of the Fuzzy MPPT technique, the obtained total harmonic distortion (THD) of the output voltage without filter circuit and with filter circuit are within IEEE standard 519.