3-dimensional finite-element solvers for the design of electrical equipment

In order to design electrical equipment to meet normal and abnormal operating conditions reliably and with economy in materials, advanced computational aids are needed. This has led to the development of three-dimensional electromagnetic/electrostatic solvers capable of modelling nonlinear materials and, in the electromagnetic case, eddy currents. The paper describes the development of three-dimensional scalar potential finite-element solvers, starting with the straightforward magnetostatic/electrostatic case. This solver is then extended to include the effect of eddy currents by the surface impedance method, and finally, the full three-dimensional eddy current problem is tackled, using the 3T-Omega (the vector electric potential-scalar magnetic potential) approach. Examples of practical applications are given, and experience with ICCG routines discussed.