The method of scalar magnetic potential using imaginary magnetic charges is employed effectively for the calculation of the electromagnetic fields in superconducting electric machines. The computing model consists of several single layers of magnetic charges. Finite-difference numerical techniques are utilized for the computation. The cylindrical coordinate system has been used for the calculation of the electromagnetic losses inside the electromagnetic shield of the rotor winding. The tangential and axial components of eddy currents have been taken into account. Linear magnetic charges replace rotor and stator currents; and surface magnetic charges replace the eddy currents inside the electromagnetic shield of the rotor winding. Various systems of partial differential equations have been formulated for the computer-aided analysis of this problem.


Author's manuscript; originally published in IEEE Transaction on Magnetics, Vol. MAG-12, No. 6, pp. 1048-1049, November 1976.


magnetic charges, electromagnetic shields, computing models, electric machinery, scalar magnetic potential, finite difference numerical techniques, cylindrical coordinate systems, rotor windings, eddy currents, stator currents

Subject Categories

Electromagnetic fields, Shielding (Electricity), Superconductors, Finite differences


Electromagnetics and photonics



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