An Advanced Switched-Capacitor Multilevel Inverter Topology With a Robust PWM Controlling Technique and Voltage Boosting Property for the Grid-Connected Renewable Energy Applications

This article proposes an improved switched-capacitor multilevel inverter (MLI) that utilizes fewer components. The switched capacitors (SCs) are employed with the dc sources in the proposed configuration to minimize the number of dc-links in the structure, which keeps the structure compact and combinable. Those capacitors enjoy a self-charging susceptibility with the ability to balance naturally. The suggested structure supports the expansion process to catch up with satisfactory output power levels based on a slight increase in the components count. The targeted application for this inverter involves a renewable energy system (RES) to exploit the extracted electrical power and inject it into the grid. This article suggests a developed PWM controller to control the system's operation. The controlling scheme has the ability to adjust the balance in the dc-links voltages to keep generating a regular output voltage. Furthermore, it helps in extracting the maximum available power from renewable resources. Meanwhile, the controller injects the real power component into the grid, which guarantees the unit power factor operation and enhances the grid's performance. The simulation results for both sides of RES are carried out in MATLAB/Simulink, and these results are verified experimentally through the dSPACE-1103 hardware.

Automated summary

This article presents an improved switched-capacitor multilevel inverter (MLI) with fewer components. By using switched capacitors (SCs) with the dc sources, the proposed configuration reduces the number of dc-links and maintains a compact and combinable structure. The suggested structure allows for expansion to achieve higher output power levels with a slight increase in component count. The inverter is designed for a renewable energy system (RES) to extract and inject electrical power into the grid. A developed PWM controller is proposed to control the system's operation, ensuring balanced dc-links voltages and maximum power extraction from renewable resources. The simulation results are verified experimentally using dSPACE-1103 hardware.