Design of Fuzzy Logic Controlling of a Single Phase 9-Level Grid-Connected Inverter for Photovoltaic system using Filter

Abstract

The proposed system a fuzzy controller is employed for improving the overall performance of existed seven level multilevel inverter for grid connected photovoltaic system where we reduced total harmonic distortion(THD) and also improvised wave shaping as compared to traditional seven level inverter.In this paper we employed three identical reference signals (Vref1, Vref2, and Vref3) with offset value similar as amplitude of the triangular carrier (V carrier) signal to produce the PWM signals. PV based inverter providing seven levels of output voltage and its functionality is to recounts and enhancement of novel modified H-bridge single phase multilevel inverter, it has two diode bidirectional switches and a novel pulse width modulation technique. By supervisory the modulation index, the necessary number of levels of the inverter’s output voltage can be accomplished. Also this topology had benefits in MPPT system. Multilevel inverter with FUZZY control implementation gains in better-quality output waveform, reduces the THD and fast error correction. The proposed system was verified through MATlab/Simulation program.