Researchers are exploring various inverter designs, including a single-phase seven-level switched capacitor with common ground inverter. Different outlets are reporting on various related designs, including seven-level, nine-level, 13-level, and 25-level inverters, with some focusing on specific techniques such as phase-shift modulation or modified SPWM. The designs appear to be focused on improving efficiency and reducing device count for applications such as grid integration and solar PV systems.