Simulation and analysis of midpoint potential balance control method based on space vector modulation

Using a T-type three-level inverter as a model, this study analyzes the causes of midpoint potential imbalance from the perspectives of topology and space vector control strategy. To address the issue of midpoint potential imbalance, a closed-loop control of the upper and lower bus voltages is proposed to adjust the redundant small vector action factor, thereby changing the PN small vector action time and regulating the midpoint potential balance.