Using genetic algorithm and simulated annealing for 27-level PV inverter THD minimization

Multilevel inverters have many advantages such as low cost, good efficiency and etc, and some application such as PV panels and fuel cells. Cascaded H-bridge MLI is one type of these MLIs. Up to now, different methods for acquiring switching algorithm have been proposed. In this paper, minimization of THD by adjusting switching times of switches is used for a 27-level inverter. For this purpose first THD is defined as a function of these switching angles and then for minimization of this function, two optimization algorithm is used: 1-Genetic Algorithms 2- Simulated Annealing. After achieving these angles, a 27-level inverter one time with ideal DC voltage sources and one time with detailed PV cells as DC voltage sources is simulated and a FFT analyses is done.