Multiplanar Eddy Current Analysis of Interior Permanent Magnets in Synchronous Machines

Eddy currents in permanent magnets of synchronous machines may cause their demagnetization due to overheating. Thus eddy current analysis has been discussed widely. 3D transient analyses of eddy current losses yield most accurate results but are also performed at very high computational cost. A previously introduced more efficient 2D approach for accurate eddy current calculation is adapted in this publication for the use with interior permanent magnet machines. Instead of only considering axial eddy currents inside the magnets, radial eddy current displacement is considered by analyzing the magnets in multiple sectional planes. The computed results comply with the theoretical expectations and the results from a 3D simulation. This confirms the method's applicability as a quick and accurate alternative to costly 3D eddy current simulations.