Analysis of Eddy Current Loss in Axial Permanent Magnet Coupling

The eddy current (EC) loss is analyzed in the isolation shell (IS) of axial permanent magnet coupling (PMC). The eddy current caused by the variational magnetic field makes the magnets temperature increase and the magnet performance degrade, reducing transmission efficiency of Permanent Magnet Coupling(PMC). Distribution of the magnetic flux density in the magnetic gap is determined by the equivalent current method and EC loss is analyzed by using the magnetic flux density. The calculation shows that EC loss would decrease with the relative angle between the driving and the driven magnets increasing. The loss would increase with the thickness and conductivity of IS increasing. An expression for the engineers to estimate average EC loss is given by the factor analysis.