Application of the optimal minimization of the THD technique to the multilevel symmetrical inverters and study of its performance in comparison with the selective harmonic elimination technique

Many interesting modulation strategies reported in literature are suitable to control multilevel power converters which presents several advantages over the conventional two-level counterpart. Since each of themes have its proper advantages and disadvantages, these strategies can be chosen according to certain performance aspects, which are required or desirable. The general performance specifications are: reducing harmonic distortion, reducing power losses and speeding transient response. In which, the harmonic elimination method and the optimal minimization technique are very important for reducing the harmonic distortion. In order to know which what control techniques the harmonic performance can be greatly enhanced or substantially improved, a detailed comparison between these two latest techniques with interpretation of its simulation results is the focus of this work