Simulink based optimization of SPWM multilevel inverter with phase shift and dual carrier at each level

摘要

This paper proposes the H-Bridge multilevel circuits with sinusoidal pulse width modulation (SPWM) and double carrier for each level with different phase shifts from 3.75°-90°. Operating principle with switching functions is analyzed from five to twenty five (odd) levels SPWM inverter and simulated to alleviate harmonic components of output voltage. By observing the THD and fundamental component of different levels the optimum level of inverter is obtained for a constant 325V dc battery supply and for variable dc-supply by keeping output as 230Vrms.