The investigation and development of a multi-level voltage source inverter

This paper discusses the control requirements for three and five level inverters, and outlines design considerations for the construction of 11 kW prototypes. Expansions to the common sampled PWM methods are described, with extensions for the control of the neutral point, and harmonic reduction. This is compared to the space vector modulation techniques. Theoretical discussions are backed by experimental results (for the three level inverter) and simulation (five level inverter).