Novel approach in investigating the rotor lamination iron losses

3-D FEM Investigation of Eddy Current Losses in Rotor Lamination Steel Sheets

“…A test sample made from the same material as the magnetic core (electrical steel of equivalent conductivity and B-H curve with a silicon steel of M400-50A grade) is placed in the center of the geometry with a DC winding on it. In addition, an auxiliary AC excitation is placed on both branches of the magnetic core in order to achieve constant amplitude of the magnetic traveling wave in the air-gap between the test sample and the AC winding [4]. It can be observed that at the top and bottom of the test sample two additional domains are modeled.…”

“…They are included in the design in order to reduce the end effects of the test setup influencing the field distribution in the middle lamination (test sample). It was concluded from the investigation in the 2D model that the main part of the AC flux is concentrated in the front half of the test sample that is closer to the AC excitation [4]. As a result, the analysis of the eddy currents loss is focused only on this area and the generated eddy currents in the rest of the test sample are considered negligible.…”

“…Consequently, the use of a measurement system that is able to emulate the field conditions from the perspective of the rotor is preferable. As it is explained in [4], none of the existing loss measurement systems have this ability. In [4], the geometry of a measurement setup capable of subjecting test samples to field conditions equivalent to the existent in the rotor of a SPSM is developed in a 2-D FEM model.…”

“…As it is explained in [4], none of the existing loss measurement systems have this ability. In [4], the geometry of a measurement setup capable of subjecting test samples to field conditions equivalent to the existent in the rotor of a SPSM is developed in a 2-D FEM model. In order to emulate appropriate magnetic conditions in the setup without any mechanical rotation, the test sample is exposed to a magnetic traveling wave which is created in the airgap g of the setup.…”

“…In order to emulate appropriate magnetic conditions in the setup without any mechanical rotation, the test sample is exposed to a magnetic traveling wave which is created in the airgap g of the setup. This traveling wave is produced only by one frequency, the effective frequency, which substitutes the sum of higher harmonics produced in the air-gap of the actual SPSM due to the interaction of the stator and rotor magnetic fields [4]. In this paper, a 3-D FEM model of this measurement setup is designed and utilized to investigate the eddy current rotor losses in laminated Si-Fe steel.…”