ABSTRACT
This chapter aims to derive the lowest total harmonic distortion of multilevel DC/AC inverters from 3-level to 81-level. This kind of multilevel DC/AC inverter can be applied in renewable energy systems, electrical vehicles, and other industrial applications. A higher level of inverter will be considered to produce output with less harmonic content. Switching angle is the moment of the level change. The equal-phase (EP) method is derived from the simplest idea, to averagely distribute the switching angles in the range 0–π. Since the multilevel waveform determined by the EP method looks very narrow, like a triangle waveform, another approach called the half-equal-phase method to arrange the main switching angles can obtain a wider and better output waveform. The idea is that when the function value increases to the half-height of the level, the switch angle is set and thus a better output waveform obtained.
