Research on the Optimization of 3D-SVPWM Modulation Algorithm for Hybrid Multilevel Inverters in ABC Coordinate System

The hybrid multilevel topology structure, without increasing the number of switching devices, can enable the conventional inverter to output a higher level, the harmonic distortion rate of the output waveform to be lower, and the withstand voltage of the switching devices to be lower by adjusting the proportion of the DC terminal voltage. This paper takes the hybrid four-level inverter and the hybrid five-level inverter as the research objects, and conducts an in-depth study on the 3D-SVPWM modulation algorithm problem of the asymmetric hybrid multi-level topology structure in the ABC coordinate system. The proposed method was theoretically and experimentally verified on the simulation model in the MATLAB environment and the small-scale experimental verification platform. The experimental results confirm that this scheme significantly improves the output power quality. It not only effectively suppresses harmonic interference but also optimizes the operating frequency of power devices, fully demonstrating the practical value and engineering applicability of the proposed control strategy.