FINITE-ELEMENT TORQUE CALCULATION IN ELECTRICAL MACHINES WHILE CONSIDERING THE MOVEMENT

In this paper different methods are presented for the calculation of torque as a function of rotation angle in an electrical machine. These methods are integrated in a calculation code by using the finite element method. The movement is taken into account by means of the technique of the Moving Band, constituted by quadrilateral finite elements in the airgap. The torque is calculated during the displacement of the moving part by using the following methods: Maxwell stress tensor, Coenergie derivation, Coulomb's virtual work, Arkkio's method and the Magnetizing current method. The results obtained by the different methods are compared with experimental data and allow to deduce practical informations concerning the advantages and limitations of each method.