The Technique of Voltage Level Time Division Based on Maximum Pulse Width to Reduce Total Harmonic Distortion on Multilevel Transformerless Photovoltaic Inverter (MLTPVI) System

An inverter is an important component used to generate alternating current (AC). One of the most common types is the multilevel inverter (MLI), which generates an AC multilevel voltage waveform. This device is designed from a simple topology with the power switching components in the full-bridge circuit connected in a series connection. The circuit consists of a total harmonic distortion (THD), voltage total harmonic distortion (VTHD), and current total harmonic distortion (CTHD). However, creating a suitable MLI technique capable of generating AC multilevel voltage waveform to achieve the lowest harmonic is one of the problems commonly faced. Therefore, this research aims to design a voltage level time division based on maximum pulse width to reduce THD on a multilevel transformerless photovoltaic inverter (TPVI) system. The direct current supplied to this is from the photovoltaic (PV) module. This research also aims to generate the phase delay time and pulse width of waves by proposing a division factor, n, proposed through mathematical modeling and simulated using SIMULINK Matlab. The results showed that the modeled PV is valid to the datasheet, therefore, it is suitable to supply the 11-level TPVI system. Furthermore, the proposed technique has the ability to generate the AC 11-level voltage waveform with different division factors, n. The lowest VTHD and CTHD are achieved at values of 8, respectively.