Sinusoidal PWM for Flying Capacitor Voltage Balancing of a Six-Level Inverter

This paper presents a control technique developed based on Sinusoidal Pulse Width Modulation (SPWM) to control the flying capacitors voltages' of a recently published six-level topology inverter. The presented inverter has a fewer number of components compared to the existing six-level topologies, which makes it a cost-efficient solution for medium-voltage applications. To produce a six-level voltage at the output of the inverter, the flying capacitors voltages should be controlled at their nominal values. The six-level inverter is controlled based on Space Vector Modulation scheme (SVM), which is complex and not convenient to implement. Therefore, a control method based on Sinusoidal Pulse Width Modulation (SPWM) technique is developed to control the capacitors voltages at different operating conditions. The simulation results in MATLAB/Simulink environment has been obtained to show the performance of the developed control method. A prototype of the proposed inverter is implemented, and the experimental results are given to show the feasibility of the proposed inverter with the developed control technique.