Z-SOURCE MULTILEVEL INVERTER FOR PHOTOVOLTAIC APPLICATION

ABSTRACT -This paper presents Z-source multilevel inverter (ZS-MLI) for photovoltaic (PV) application. MLI possesses the advantage of higher power capability and can operate with higher voltage level. As the number of levels increases, the desired sinusoidal waveform can be obtained for lower total harmonic distortion (THD). MLI has a limitation, that it cannot boost the output ac voltage (V peak-ac ) greater than the dc voltage coming from the PV. Z-source network followed by the diode clamped multilevel inverter (DC-MLI) is used to boost up the output voltage to a desired value. Phase disposition pulse width modulation (PD-PWM) technique is used to generate the PWM signals for the inverter switches. The simulation of single phase, seven level Z-source DC-MLI is carried out using MATLAB/SIMULINK. KEY WORDS-Diode clamped multilevel inverter, Phase disposition pulse width modulation, Photovoltaic, THD, Z-source inverter, Z-source multilevel inverter