A system to place one or more rovings made from composite material on a substrate. The system includes at least a roving-laying head configured to lay at least one roving, an electricity generator and at least one plasma torch. The plasma torch mounted on the roving-laying head and powered by the electricity generator. The plasma torch being further supplied with at least one plasma-forming fluid to generate at least one plasma jet suitable for heating the one or more rovings to be laid on the substrate.