Most arc plasma systems are based on DC plasma technologies. However AC plasma systems can offer significant advantages versus DC plasma systems particularly in terms of efficiency, cost and reliability. They are also likely to overcome some of the limits of classical DC systems for some specific large scale high power applications. This paper presents a literature review of three-phase AC plasma systems which have been developed by the most active research groups on multi-phase AC plasma systems in the United States, Norway, Germany, Russia, France, and Japan for about 50 years.