Abstract: A method and a system for controlling the path of movement of an orbital motion welding system are provided. The locus path of a voltage space vector of a frequency converter feeding the electromechanical system is adjusted by an oscillation amplitude controller with respect to amplitude by using a path controller working in a rotating coordinate system, and a voltage generator. The adjustment is done with respect to the spectro-composition (relative amplitude and phase of the harmonic oscillations) so that the resulting path of movement equals the desired path of movement. The paths of movement obtainable with the invention include all kinds of ellipses including circular and linear paths of movement along one axis as extremes.