Patent attributes
A plasma generator for three phase mains alternating current operation has three plasma generation tubes interconnected with a nozzle, each plasma generation tube having a plasma initiator for forming a plasma into an electrode ring, the electrode ring including substantially tangential gas introduction orifices which cause gas entering the electrode ring to helically rotate. Each of the electrode rings is coupled to a unique one of the three phases of AC voltage supply, such that when the initiator plasma is introduced into one of the electrode rings, a plasma discharge occurs with a path from the electrode ring, through the plasma generation tube, and to a different electrode ring. Each electrode ring has gas introduced in a helically rotating manner such that the erosion of the surface of the electrode ring is uniform over the entire surface, and minimally erosive in a single arc attachment spot, since the arc spot is constantly moving as provided by the helical trajectory of the gas entering the electrode.
