Center-Tapped π-Type Single-Phase Cell

A π-type derived four-level single-phase inverter is analyzed in this paper. It is demonstrated that the topology can be obtained both by inserting a neutral connection point in a four-level π-type cell, or removing the switches connected to ground in a five-level T-type cell. Five different pattern approaches to drive converter switches are presented, showing its influence on the high-frequency waveform of the output voltage. Simulation results for scenarios of feeding a single-phase load and a solar array connection to grid are given, making possible to demonstrate its functionality.