Abstract:

According to the theory of electromagnetism and the fundamental mechanics theory,for a 405MVA/500kV converter transformer,apply the simulation software MagNet was applied to establisha three-dimension symmetric finite element model with local unbalanced ampere turns and tank wall.The simulation of short-circuit impedance  proved the accuracy of the harmonic analysis method.The short-circuit electromagnetic force was then calculated.Then the "Spring-Quality-damping" was established through ANSYS and realized the modal analysis,was realized.Action law of inertia force and elastic force applied on winding disks in the changing vibration system with points asserted multi-load and multi-degree-of-freedom was further discribed,and the distribution on line side windings of inertia force and elastic force,as well as effect on axial vibration stability of the two forces was also discussed.At last,spectrum analysis was corried out for elastic force with the method of Fourier Transform to obtain the  distribution of vibration form and energy on winding disks during vibration,and test the vibration stability for the converter transformer windings was tested.

Key words: transformer, winding, inertia force, elastic force, axial vibration