Selective Harmonic Elimination Technique for a 27-Level Asymmetric Multilevel Converter

In this paper, we present an implementation of selective harmonic elimination modulation technique in a 27-Level asymmetric multilevel converter. The main issue kind converters is the generation gating patterns to obtain optimized AC voltage waveform. State-of-the art solutions use deep mathematical analysis frequency domain by means Fourier series, but they are mainly applied for two-level or symmetric converters. On other hand, focused on nearest level control vector control. work, propose novel modulating that takes advantage switching angles optimization 27-level fact, different set obtained and presented order define index as well value A sweep was performed entire operating region converter, where it can be observed number levels decreases when low, which calculated minimize total distortion (THD) resulting validate proposal, these results indexes values simulated, obtaining THD < 5% 0.75<M<1.0. Finally, small scale proof-of-concept prototype implemented proposal.