Generalized Structure for Three-Phase Switched-Capacitor Boost Inverter With Adapted Space Vector Modulations

This article proposes a new generalized switched-capacitor (SC) boost inverter structure to supply three-phase loads from low-magnitude dc input voltage. This proposed structure controlled with a modified space vector modulation (SVM) allows the inverter to work with an extended range of voltage without need of classic dc/dc boost converter. Moreover, the new structure is capable of generating multilevel output voltages, leading to the elimination of large inductors, thereby reducing the converter's weight, volume, and power losses. The present structure is formed using a cascade of SC circuits. Three new adapted SVM based on the concept of virtual space vector were proposed. The performance of the proposed structure and its adapted modulations is evaluated using MATLAB/Simulink simulations based on RL load and has been verified through experimental implementation. In addition, power losses, efficiency, and thermal performances are studied using PLECS software and compared against the conventional boost inverter. The proposed structure broadens the inverter's voltage range while preserving a near-sinusoidal waveform. Among the proposed SVM techniques, SVM1 displays promising results and is the simplest to implement. SVM2 and SVM3 yield multilevel output waveforms with lower total harmonic distortion (THD) and higher efficiency. Overall, this structure holds potential for photovoltaic (PV) system applications.