On rotational eddy current losses in steel laminations

It is analytically shown that rotational eddy current losses are exactly equal to the sum of eddy current losses for two unidirectional and orthogonal components of magnetic flux density acting separately under the assumption that the peak value of the magnetic flux density is uniform over a lamination cross-section. By using exact analytical solutions, the rotational eddy current losses are also evaluated when the peak value of the magnetic flux density is nonuniform.