FUZZY LOGIC CONTROL FOR SINGLE PHASE MULTILEVEL INVERTER

Abstract

A single phase cascaded inverter consisting of two full bridges creates a five level AC output voltage. Due to switch combination redundancies, there are certain degrees of freedom to generate the five level AC output voltage. A single phase Pulse Width Modulation (PWM) Multil Level Inverter (MLI) produces AC output voltage of desired magnitude and frequency. The purpose of voltage controller for the inverter is to produce regulated output voltage with low distortion under all loading conditions. A Fuzzy Logic Controller (FLC) is developed using Matlab-Simulink for the chosen inverter having application in Uninterruptible Power Supplies (UPSs). For comparison purposes, a PI controller is also developed. The results are presented and evaluated. FLC is found to have better performance.