Comparisons of PWM and one-cycle control for digital power amplifiers

A new paradigm existing for inverter control is a one-cycle method which can effectively reduce the harmonic components from inverters. Based on the concepts of cascaded multilevel converters and one-cycle technique, a comparison was conducted to characterize the distortion of PWM and one-cycle control methods that were applied to inverters. Simulation programs for the different control schemes were run in PSIM software initially to see the effect of one-cycle control different from that of PWM control. Afterwards, a DSP control board was designed and programmed to control an inverter under different control strategies to compare one-cycle method with PWM method. With the comparisons, the advantages and the disadvantages are identified for each method. The one-cycle scheme is better than PWM control in reducing undesirable harmonics and tracing dynamic waveforms. Simulation and experimental results are also provided to verify the conclusions.