Partial Two-Stage Four-level Inverter for Grid-tied PV Application

In this paper, a novel inverter, termed as Triple-dc-Link Inverter (TDCLI), is proposed. This inverter uses three dc links to develop a four-level ac voltage. The utilized dc links are the input dc source, which is provided by a PV unit, and two dc voltages that are developed by using a unique dc-dc stage. Hence, only one dc source is required to synthesize the TDCLI. In grid-tied Photovoltaic (PV) application of the proposed inverter, the leakage current, one of the main problems in grid-tied PV systems, is tackled. The other feature of the proposed inverter is developing a four-level boosted voltage that reduces the Total Harmonic Distortion (THD) value. The simulations are provided to lend credence to the viability and feasibility of the proposed inverter.