In this study, design and performance aspects of a 343-level asymmetrical cascaded inverter system specially designed for renewable energy systems are presented. The proposed inverter is operated and analyzed under three distinct configurations. The system is designed using unequal DC voltage sources with the structure (1:2:7:14:49:98)Vdc, producing a 343-level output. In the first case, Vdc is set to 1 V (per-unit system), while in the second case it is set to 40 V, resulting in actual voltages of (40:80:280:560:1960)V with a total maximum of 3920 V. In the third case the Vdc sources are replaced with photovoltaic (PV) modules. The simulations reveal that the inverter provides improved performance in producing low-distortion voltage and current waveforms closely approximating a sine wave. With the per-unit voltage case and power factor of 0.92, the inverter realizes an RMS voltage (VoRMS) and current (IoRMS) of 120.9316 V and 3.7178A, and total harmonic distortion of voltage (THDVo) and current (THDIo) of 0.32422% and 0.22506%, respectively. While with actual voltage values and power factor of 0.97, the results set VoRMS of 4838.7577 V and IoRMS of 6.7445A with THDVo of 0.32414% and THDIo of 0.25682%. For the PV module configuration with a power factor of 0.92, the inverter records VoRMS of 4827.9768 V and IoRMS of 148.4073A with THDVo of 0.90328% and THDIo of 0.54142%. These results show the flexibility of the inverter to deliver an enhanced power output with low harmonic distortion and the suggested inverter has significant potential for use in modern renewable energy systems and industrial applications.
