permulator

from The Collaborative International Dictionary of English v.0.48
Permulator \Per"mu*la`tor\, n. (Elec.)
   A special form of rotary converter with stationary commutator
   and rotating brushes, in which the exciting field is induced
   by the alternating current in a short-circuited magnetic core
   instead of being produced by an external magnet.
   [Webster 1913 Suppl.]
    

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