New special system of polynomial equations for 3-phase multilevel voltage converter derived from the PWM problem for 1-phase inverters

This paper presents a new construction method of a new set of polynomial equations leading to the optimal solution of switching angles which minimize the total harmonic distortion (THD) of a three-phase multilevel converter. The number of equations obtained by this method is lower compared to previous methods. It is possible to solve the problem more simply. This method is based on analytical solution of the PWM problem in single-phase connection which is very fast and efficient and gives the conjunction between both problems.