Èlektron. model. 2017, 39(5):105-112
It is shown on the basis of analysis for electrotechnical model of commutation process in the contact zone of rail accelerator of macrobodies that surface resistivity of electrodes of a contact pair is a necessary condition for favorable commutation of current in electromechanical transducers with a sliding contact. In the model of accelerator which has the increasing resistivity of the rail surface layer along with the rise of armature motion velocity it is shown that the volume Joule’s losses in the skin layer per unit of rail length can be constant in spite of its resistivity growth, so causing no additional superheating of the conductor. A discussion is performed concerning similar situation in the rotating commutator machines.
sliding contact of machines, problems of commutation, resistivity of contact surface, application in rail accelerator, similarity with rotational machines.
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