Novel cascaded tilt fractional-order integral derivative with a proportional integral for harmonics mitigation in 31-level multi-level inverter

Abstract

Alternate current (AC) motor drives and distributed power generation systems often use inverters, which are also known as DC-to-AC power converters. Multi-Level Inverters (MLIs) have emerged as the preferred inverter technology due to their benefits of lower switching losses and improved harmonic profile. In this article, an innovative controller topology for reducing total harmonic distortion (THD) in the 31-level MLI is proposed. A cascaded controller consisting of tilt fractional order integral derivative with proportional integral controller (C-TFOID-PI) is proposed for optimizing the switching angles of the MLI. Green anaconda optimization algorithm (GAOA) is included in this work to select the optimal gain parameters in the novel controller with minimum error. A single-phase 31-level asymmetrical cascaded MLI is utilized in this work to validate the proposed controller with the optimization method. By simulating the entire procedure with MATLAB/Simulink, the control performance of the proposed system is verified. In order to demonstrate the superior performance of the proposed C-TFOID-PI controller and optimization method, its performance is contrasted with that of other controllers. The proposed controller topology effectively lowers the THD to 0.41 %, which is 2 % better than a fuzzy logic controller. Also, the proposed inverter topology improves efficiency by 3.9 % and reduces losses by 1.02 % when compared with other controllers.