Triangular finite element solutions for moving conductor eddy current problems

This thesis examined possible finite element solutions for moving conductor eddy current problems by focusing specifically on those based on triangular elements. Attention was directed towards overcoming the difficulty of numerical stability, which is a consequence of the introduction of the motional terms into the governing equation.; The expressions for the triangular upwinding formulation have been re-derived in detail and the numerical performance of this method has been examined. Numerical results have demonstrated that the triangular upwinding method can successfully suppress spurious numerical oscillations and produce solutions with acceptable accuracy.; A novel form of the weighting function for triangular elements has been constructed for the first time. This method is based on the elimination of factors which could lead to spurious numerical oscillations by employing a set of non-conventional exponentially fitted weighting functions. Numerical results have shown that certain improvements in accuracy over the triangular upwinding method can be achieved by the new triangular elimination method, which also provides a unique alternative over triangular elements to the use of the exponentially fitted weighting function for the solution of the moving conductor eddy current problems.; A 2D motion solver was implemented using the triangular upwinding method due to its flexibility for more general problems and its similarity to the Galerkin formulation in terms of implementation. This solver was designed to make full use of the pre and post processing capabilities of an existing commercial finite element code, MagNet, and to be able to handle AC excitations. The new motion solver was used to evaluate the performance of a full size linear induction motor used in transit drives, and can serve to enhance MagNet's solution capabilities by including eddy current problems with the motion.