On the Importance of Incorporating Iron Losses in the Magnetic Field Solution of Electrical Machines

This paper studies the effects of iron losses on the magnetic field solution and evaluates their impacts on the overall performance of electrical machines. Because of the complications associated with the inclusion of iron losses into the magnetic field solution, the losses are usually omitted from the finite-element (FE) analysis while they are estimated in a post-processing stage. We conducted a comprehensive FE analysis to study how the iron losses affect the accuracy of the magnetic field solution and what kind of role the losses play in defining the behavior and operation of electrical machines. We found that the inclusion of iron losses in the FE field solution of rotating electrical machines is primarily important for predicting iron losses accurately. Other electrical and mechanical quantities, including input power, supply current, power factor, copper losses, and rotational speed are only slightly affected by iron losses. Therefore, we have proposed an empirical equation that can be used to correct the iron losses that are calculated from the post-processing of the FE solution.