A Proposed PSO-Based Modified SPWM Switching Technique for a Cascaded Half-Bridge Multilevel Inverter

This paper introduces a novel approach for optimizing the switching scheme of Cascaded Half-Bridge multilevel inverters. Compared to traditional types of multilevel inverters, this topology has fewer switching components. The proposed technique involves utilizing sinusoidal pulse-width modulation, which stands out for its simplicity, as it relies on a one modulating signal and a triangular signal that is compared against a solitary carrier. Implementing the particle swarm optimization method, the switching operations of each level in the cascaded half-bridge multilevel inverter are fine-tuned to minimize the total harmonic distortion. The effectiveness of the proposed technique is demonstrated by implementing a comprehensive simulation in a single-phase seven-level inverter. The proposed technique’s simulation results are meticulously compared to those obtained via the equal-step method. THD was minimized by 29.75% without implementing a filter. Moreover, to validate the experimental feasibility of the proposed scheme, a complete laboratory system is constructed, employing the dSPACE CP1104 kit. The experimental results exhibit a satisfactory concurrence with the simulation outcomes, thereby affirming the reliability and efficacy of the proposed scheme.