Radial and Axial Short-Circuit Electrodynamic Forces of Three Phase Power Transformers

The paper presents a method for calculating the axial and radial forces acting on the windings of a three phase electrical power transformer, during shortcircuits, using 3D finite element method and a 2D analytical method. The obtained results are compared showing that differences by the two methods are small. The calculations are made for a three phase transformer with concentric cylindrical layered windings, symmetrically placed inside the window. The work validation is obtained by conducting measurements of the dispersion magnetic field of the transformer by comparing the measured values of the radial magnetic flux density during rated operating regime of the transformer, with the values calculated by 3D finite element method, showing that these values are very close.