The paper introduces a network description of conducting regions in electrical machines. Resistance models are considered, where loop equations are equivalent to an edge element formulation using the electric vector potential , as well as conductance models, for which the nodal equations refer to a nodal element description by means of the scalar potential . Network models for multiply connected regions are derived for both --0 and --0 formulations. A network representation of the edge value of potential 0 is suggested.Convergence of the iterations of the -0 method may be accelerated by supplementing equations for the edge values of 0 .

The paper offers a comparative study of numerical methods of analysis of electromagnetic fields. The focus is on the finite element method (FEM) and finite integration technique (FIT), but with the cell and equivalent network approaches also considered. It is shown how the approximate integrals describing coefficients of the FEM need to be derived for a mesh with parallelepiped elements to achieve consistency with FIT equations. The equivalence of FEM and FIT formulations for a triangular mesh in 2D is highlighted. The TEAM Workshops Problem No. 7 is used as an example for numerical comparisons. Two formulations have been considered: 1) using the edge values of the magnetic vector potential and the nodal values of the electric scalar potential ; and 2) expressed in terms of the edge values of both magnetic and electric -0 vector potentials.Index Terms-Eddy currents, electrical engineering education, finite element method (FEM), finite integration technique (FIT), magnetic circuits.

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The paper discusses methods of calculating induced currents in multiply connected regions containing solid conductors. In particular, the formulation based on edge elements using the electric vector potential has been considered. The equations are explained using the language of circuit theory. It is observed that the edge values of T 0 represent the loop currents in the loops surrounding the 'holes'. It is also shown that the iterative solution may be accelerated by over-specifying the number of loop currents in the loops around the 'holes'.

The paper focuses on the analysis of the asynchronous torque of the line start permanent magnet synchronous motor (LSPMSM) with the asymmetrical squirrel cage winding. In order to calculate the asynchronous torque the parametrical fieldcircuit models of LSPMSM have been elaborated on. Further, the models have been applied to investigate the impact of squirrel cage asymmetry on the asynchronous torque. The evaluated asynchronous torque vs. rotor speed characteristic of proposed motor with asymmetrical cage has been compared with the characteristics of reference asynchronous motor and LSPMSM with symmetrical cage winding. It has been found that deepening of chosen bars of the cage improves the starting properties of the LSPMSM.