Selective Harmonic Elimination for an Asymmetrical Multilevel Converter

In this paper, a novel asymmetrical multilevel converter is proposed which is composed a 3-level leg and a 2-level leg. The principle of the converter is analyzed. The new schema requires fixed insulated supplies instead of capacitors. Selective harmonic elimination method is used to eliminate the specified harmonics in the output voltage. Then the switching angles are computed to eliminate the low order harmonics in theory. A 6-level laboratory test verifies the proposed method.