Elimination of Harmonics in Multilevel Inverters Connected to Solar Photovoltaic Systems Using ANFIS: An Experimental Case Study

Abstract

In this study, a multilevel inverter was designed and implemented to operate a stand-alone solar photovoltaicsystem. The proposed system uses pulse-width modulation (PWM) in the multilevel inverter to convert DC voltagefrom battery storage to supply AC loads. In the PWM method, the effectiveness of eliminating low-order harmonicsin the inverter output voltage is studied and compared to that of the sinusoidal PWM method. This work also usesadaptive neuro fuzzy inference (ANFIS) to predict the optimum modulation index and switch angles required for afive level cascaded H-bridge inverter with improved inverter output voltage. The data set for the ANFIS-basedanalysis was obtained with the Newton-Raphson (NR) method. The proposed predictive method is more convincingthan other techniques in providing all possible solutions with any random initial guess and for any number of levelsof a multilevel inverter. The simulation results prove that the lower-order harmonics are eliminated using theoptimum modulation index and switching angles. An experimental system was implemented to demonstrate theeffectiveness of the proposed system.