A comparative Analysis of Multi-Level Inverters Supplied by Photovoltaic Panels based on THD and Filter Size by using POD-SPWM Technique

Abstract

Abstract Solar Photovoltaic (PV) power is one of the favourable renewable energy resources in the globe especially in Iraq. The main benefits of solar energy are dependability and availability. The important roles for construction of a PV power plant are decreasing the cost of its components, simplifying the complexity of its controllers and improving its performance to meet the grid standards. In this paper, single stage PV Generators (PVGs) connected with Cascaded H-Bridge Multilevel Inverter (CHB-MLI) are designed and analyzed. Four MLI topologies are demonstrated, which are three, five, seven and nine levels, for improving the efficiency of multilevel inverter, reducing drop voltage and total harmonic distortion (THD) value for the output voltage and current by decreasing the inductance value of L filter in load side. In this paper, Phase Opposition Disposition based on Sinusoidal pulse width modulation (POD-SPWM) technique is used to control the proposed MLI circuits. In this technique, the reference signal is a modulating sine of 50 Hz frequency is compared with a carrier signals of 50 kHz to produce optimal switching combinations that achieve numerous levels of output voltage. Simulation work is done using the MATLAB software. The simulation results confirm that the performance and the cost of nine-level topology is improved compared with the three, five and seven levels topologies.