Optimization of analytical iron loss approaches for electrical machines

The accurate analytical calculation of iron losses in electrical machines is still a great challenge for designers of electrical machines. There are a lot of different analytical approaches applying in order to reach good results. Comparisons between the analytical approaches and measurements of the specific iron losses of unmachined electrical sheets show that the loss coefficients of the approaches strongly depend on the operating range of the magnetic flux densities and frequencies. In order to keep the discrepancy between measurement and approaches depressed it is reasonable to calculate the loss coefficients depending on its application. In this paper several calculation methods are discussed and the loss coefficients are determined for particular application cases. As a result the error of calculation and measurement can be kept small. Obviously discrepancies due to the different process steps during the manufacturing process have to be considered by correction factors as well.