Propositions for the analysis of commutation phenomenon and the modeling of universal motors based on introducing the state function method into FEM electromagnetic field analysis

The universal motors of our advanced research use FEM simulations to perform modeling of universal motors rotating at ultrahigh speed by using the like state function method with respect to the details regarding the commutation scintillation phenomenon of the commutators, the air gap surface, and the contact condition of the brushes. As a result, at the design stage, the commutation scintillation phenomenon was quantitatively estimated and an investigation was performed with respect to the configuration of the iron core. Furthermore, an example of this modeling method based on FEM analysis was performed with regard to the electromotive force of the transformer, the armature reaction and the scintillation voltage including the contact resistance of the brushes resulting from the rotation, the configuration of the iron core, and the changes in the gap permeance. Regarding the validity of this analysis, an extremely close match was attained between the results of the present simulation and the experimental results. In this regard, the target model motor was a 1.5 kW, 33,000 rpm ultrahigh speed, high-capacity universal motor for cleaners.