Broyden's method assisted differential evolution (BMADE) based selective harmonic elimination in a cascaded H-bridge multilevel inverter

This paper implements Broyden's Method Assisted Differential Evolution (BMADE) algorithm for eliminating third and fifth harmonics in the output voltage of 7-level cascaded H-Bridge multilevel inverter (CHB-MLI) using selective harmonic elimination technique. Calculations of switching angles are done for various modulation index values (M). Initial guess for Broyden's method is calculated by Differential Evolution (DE). Exact value of switching angles is then calculated by Broyden's method using initial guess obtained from DE. Code of BMADE algorithm for obtaining the required switching angles is written in MATLAB. Results obtained with BMADE algorithm are compared with various other techniques that is, Genetic Algorithm (GA), DE, and Whale Optimization Algorithm (WOA). BMADE is able to successfully eliminate third and fifth order harmonics in the output voltage. Along with removing the desired harmonics, BMADE also provides lower THD than GA, DE, and WOA for certain range of M. The results also showed that BMADE is faster than GA, DE, and WOA as the execution time of BMADE is lesser than GA, DE, and WOA. Moreover, laboratory experiments are used to test the simulation's findings. The experimental results support the simulation results.