Using Three-Dimensional Virtual Voltage Vector in Predictive Current Control of a Four-leg Inverter for Fixing Common-Mode Voltage

Common-mode voltage (CMV) variations result in high-frequency harmonics and leakage current in transformer-less solar systems. In order to generate high-quality output voltages, power converters often utilize pulse-width modulation to generate their switching signals. The production of a common-mode voltage also known as (CMV) via PWM techniques is a significant source of concern. In order to address this problem, the author of this study suggests using a model predictive current control (MPCC) technique in conjunction with three-dimensional (3-D) virtual voltage vectors (VVVs) in a three-phase four-leg voltage source inverter (VSI). Only a subset of the available vectors is put to use in order to lessen the amount of CMV variations and overall harmonic distortion in the output current load. With the suggested method, the waveform of CMV fluctuations is maintained at zero for the duration of each switching cycle in a four-leg VSI, and thus CMV’s high-frequency harmonics are reduced. Additionally, using three-dimensional virtual vectors in the suggested technique lowers the total harmonic distortion (THD) of the inverter’s output current. Finally, the simulation results of the two-level three-phase four-leg VSI evaluates the suggested hypothesis.