Real time PWM control converters using three elements polynomial regulators

The authors analyze the modeling of inverter-type converters along with a general method for real-time pulse-width-modulation (PWM) control using a three-element regulator. This regulator is first based on an alpha stability pole placement principle and then on the internal model principle. From an automatic point of view, robustness is evaluated using the Nyquist diagram criterion. The Wonham internal model principle is applied to reject harmonic disturbances of a given rank or to generate the full reference. Several applications are presented and compared. The algorithms presented were evaluated on a converter structure corresponding to an uninterruptible power supply.<>