Optimal Time-Domain Sinusoidal Pulse Width Modulation Technique

Abstract

An optimal time-domain pulse width modulation technique is presented for single-phase and three-phase inverters under the constraint of sinusoidally modulated voltage pulse widths. Harmonic content in currents and voltages is expressed as function of displacement factors, which characterize the placement of the sinusoidally modulated voltage pulses in each sampling subinterval. Implications of symmetries on these displacement factors for three-phase inverters are discussed. Minimization of harmonics is stated as an optimization problem, which is then numerically solved to reveal improvements in harmonic performance.