State-of-the-art carrier PWM techniques: a critical evaluation

With the introduction and wide acceptance of gate-turnoff power drives, e.g., bipolars, power FETs, GTOs, the switching behaviour of converters has reached the point where further improvements in firing and switching networks bring out only marginal benefits. Consequently, the research interests in the area of static converters have been shifting toward improving the process of power conversion through a combination of novel circuit topologies and improved voltage and harmonic control PWM (pulsewidth modulation) techniques. As a result, several such techniques have been proposed lately. Although these techniques are clearly superior to the original sine PWM technique, little or conflicting data is available about their merits relative to each other. A critical evaluation of the aforementioned PWM techniques on the basis of application is provided, thereby giving the framework and guidelines for the selection of the best technique for each area of application