Performance Investigation of a Reduced Switch Five-Level Inverter: Modelling and Simulation

Photovoltaic (PV) systems have been increasingly integrated with the AC grid because of their effectiveness as sources of sustainable energy. Since PV systems generate DC, inverters are essential for grid compatibility, with transformerless inverters preferred for their lower cost and reduced losses. However, such inverters have encountered problems of high component count and total harmonic distortion (THD). This research introduces a reduced-switch five-level inverter to decrease the number of devices and enhance the efficiency and waveform quality. All the modulation schemes-EP, HEP, HH, FF, and OHH-are experimented with, and the lowest THD is achieved by OHH, which is 16.39 %. The inverter operating modes and such stability of this inverter are verified by MATLAB simulations, displaying that the presented topology can effectively reduce THD over the conventional counterparts. A hardware prototype of the inverter was constructed and tested, confirming the results of the simulation and verifying the practical release capabilities of the inverter. The proposed topology can provide a low-cost solution for the grid-connected PV systems.