Low Order Harmonics Elimination in Multilevel Inverters Using Gradient Descent Algorithm

Abstract

In recent years, the topic of harmonics in general and the elimination of low order harmonics in power system in particular attracts the attention of many researchers in the field of power electronics. Estimation of the values of switching angles in multilevel inverters has been of interest in reduction or elimination of low order harmonics. In this paper, the technique that is based on the gradient or steepest descent algorithm is described. This algorithm searches for the minimum value of the power harmonic distortion of the low order harmonics in the output waveform, according to the value of the modulation index set at the beginning of the optimization process. The power equations of harmonics are used for this purpose and therefore a high convergence rate is obtained with this method. The results have been verified by MATLAB software.