Simplified per-phase switching loss minimization technique for PWM rectifier

Abstract

Due to the significant increase in demand for power electronics/electrical systems, the reliability of power converters is a major concern. Among existing methods, since lowering the switching frequency of the three-phase pulse-width modulation rectifier legs can significantly degrade output performance, this paper proposes a simplified per-phase switching-loss minimization technique. The proposed method specifically targets the most stressed leg of the PWM rectifier. The proposed strategy achieves this by modifying the offset term generation process and selecting an appropriate offset term to create modulation signals that reduce the switching frequency and associated losses of the most stressed leg. Consequently, the lifetime of both the most stressed leg and the entire pulse-width modulation rectifier is extended, while maintaining acceptable output performance. To validate the effectiveness of the proposed approach in minimizing switching losses and ensuring satisfactory input/output waveforms, comprehensive simulations and experimental tests are performed, along with comparisons and evaluations of the conventional and proposed methods.