Capacitor voltage balancing of a nested T-type four-level inverter using space vector modulation

In this paper, a control method for capacitor voltage balancing of a nested T-type four-level inverter is proposed. The nested T-type inverter has less number of components compared to the available four-level inverters which makes this topology attractive for high-power medium-voltage applications. In order to control voltages of flying capacitors, a Space Vector Modulation (SVM) strategy is developed that employs the switching state redundancies. Performance of the control method is investigated in the MATLAB/Simulink environment under different operating conditions.