This study develops a pulse width modulation (PWM) strategy with a view to achieve explicit control of voltage and accrue a minimum total harmonic distortion in a multilevel inverter (MLI) of any preferred level. The multi objective digital formulation tailors to facilitate discrimination of pulses for various levels and equalise the switching losses in all the power switches in the MLI. The philosophy of the method centres to calculate the pulses for the desired target fundamental output voltage based on equal area criteria. It excludes the need for a carrier in the generation of the PWM pulses through a process of matching the output level with the sectionalised dc levels and travels to determine the switching instants using mathematical relations. It includes simulation results from a MATLAB platform for a seven level MLI and avails the use of a field programmable gate array-based prototype to validate the findings.

This paper corroborates three different hybrid modulation strategies suitable for single-phase voltage source inverter. The proposed method is formulated using fundamental switching and carrier based pulse width modulation methods. The main tale of this proposed method is to optimize a specific performance criterion, such as minimization of the total harmonic distortion (THD), lower order harmonics, switching losses, and heat losses. The proposed method is articulated using fundamental switching and carrier based pulse width modulation methods. Thus, the harmonic pollution in the power system will be reduced and the power quality will be augmented with better harmonic profile for a target fundamental output voltage. The proposed modulation strategies are simulated in MATLAB r2010a and implemented in a Xilinx spartan 3E-500 FG 320 FPGA processor. The feasibility of these modulation strategies is authenticated through simulation and experimental results.

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